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Tytuł:
The next 150 years begin
Autorzy:
Larson, C. R.
Powiązania:
USNI Proceedings 1996, nr 9, s. 65-69
Data publikacji:
1996
Tematy:
Akademia Marynarki Wojennej (Annapolis, Stany Zjednoczone) reformy planowanie 1996 r.
Marynarka wojenna szkolnictwo wyższe Stany Zjednoczone 1996 r.
Szkolnictwo wyższe wojskowe Stany Zjednoczone 1996 r.
Akademie wojskowe Stany Zjednoczone 1996 r.
Opis:
Perspektywy rozwoju Akademii Sił Morskich Stanów Zjednoczonych.
Fot.
Dostawca treści:
Bibliografia CBW
Artykuł
Tytuł:
A Treatise on Dragonflies (Order: Odonata, Class: Insecta) of rice ecosystems in Eastern India
Autorzy:
Satpathi, C. R.
Powiązania:
https://bibliotekanauki.pl/articles/1178310.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Dragonfly
Nymph
biodiversity
conservation
index
rice
threat
weed
wings
Opis:
This study highlights the 75 species of dragonfly fauna associated with rice ecosystems in eastern India out of which 15 species were regular and rest were sporadic. From the general taxonomic point of view all the species were grouped under 5 families of under order Odonata. Comparing different body parts the double branching keys were prepared for easy identification of 15 common dragonfly species recorded in rice ecosystems of West Bengal. Each key begins with a couplet (a pair of alternative) and each of which leads to another couplet. Finally the reader reaches the specific identity of species. Free hand drawing of wings of the 50 dragonflies were also used for separate identification of these insect species. In addition to this, different studies were made on courtship and mating, egg laying habitats, nymphal development, longevity, flight capacity of dragonfly to make the study more interesting to the reader. The population build up of dragonfly, favors to certain altitude as well as availability of water which is reverse to the other group of insects. Three different localities were selected at 9.75 m (Chakdaha), 200 m (Cooch Behar) and 1250 m (Kalimpong) of which former two represent an unique physiographic ecological system in Eastern India characterized by extreme diversities of dragonfly inhabiting there. The studies on natural enemies of dragonfly along with their major threats indicated that about 2, 4 and 4 species were critically endangered, endangered and vulnerable in rice ecosystem of West Bengal. Dragonflies are very sensitive to changes in landscape and are reliable indicators of wetland health. Therefore the effective conservation of dragonfly depends entirely on conservation of their habitats. Different studies were made to estimate the role of dragonfly in integrated pest management of rice crop in West Bengal. An investigation was also carried out to find out the crop stage wise diversification of individual predator and found that dragonfly was more diverse during flowering to ripening stages of crop respectively. The values Simpson and Shanon diversity index showed that dragonflies are specific flowering to ripening stage of crop. Subsequently the value of Margalef index and Menhinick index also indicated that the aforesaid predators were more diverse in flowering stage of crop whereas it was least in vegetative stage of crop. From the Hill's diversity the number of abundant and most abundant species was calculated where maximum and minimum were obtained from dragonfly and staphylinid respectively. The studies on colonization and succession of major dragonfly taxa in the rice field indicated that it followed a uniform pattern in relation to growth stages as well different phases in the rice field. The studies on relative abundance of dragonfly in different ecosystems reflected that their population in fields could be conserved and enhanced through maintenance of rice weed flora on bund or allowing ratoon rice after the rice crop during fallow period. The fallow land has limited effect on incidence of insect predator in rice crop. The relative ranking chart of 50 important predators in rice ecosystem of West Bengal indicates that the insect belonging to Coleopteran (17) were top of the list whereas dragonfly was third (10). The validity of chart may increase over time and they will need to be updated periodically.
Źródło:
World Scientific News; 2017, 86, 2; 67-133
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New insights into the origin and relationships of blastoid echinoderms
Autorzy:
Paul, C.R.C.
Powiązania:
https://bibliotekanauki.pl/articles/2082286.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Blastozoa
Glyptocystitoida
Hemicosmitoida
Coronata
Blastoidea
homology
phylogeny
ontogeny
Opis:
“Pan-dichoporites” (new informal term) is proposed to unite Cambrian blastozoans, such as Cambrocrinus, Ridersia, and Sanducystis, glyptocystitoid and hemicosmitoid rhombiferans, coronates, blastoids, and Lysocystites. Pan-dichoporite ambulacra have double biserial main axes with brachiole facets shared by pairs of floor (glyptocystitoids), side (blastoid) or trunk (hemicosmitoids, coronates) plates. These axial plates are the first two brachiolar plates modified to form the ambulacral axes. In glyptocystitoids the first brachiole facet in each ambulacrum is shared by an oral and another plate. Hence, these are also two modified brachiolar plates and part of the axial skeleton under the Extraxial Axial Theory (EAT). Pan-dichoporites are also characterized by thecae composed of homologous plate circlets. The unique glyptocystitoid genus Rhombifera bears ambulacral facets on five radial plates, which alternate with five orals. The oral area of Lysocystites (blastoid sensu lato) is very similar, which suggests that rhombiferan radials are homologous with “ambulacrals” of Lysocystites and hence with blastoid lancet plates. This implies derivation of blastoids from glyptocystitoids and suggests that blastoid and coronate radials and deltoids are homologous with rhombiferan infralaterals and laterals. Thus, homologous plate circlets occur in all pan-dichoporites, which strengthens the validity of a pan-dichoporite clade. Under Universal Elemental Homology (UEH), deltoids were homologized with rhombiferan orals, but this is inconsistent with the EAT. Deltoids bear respiratory pore structures and so are perforate extraxial skeletal plates, whereas rhombiferan orals are axial skeleton. The new plate homologies also explain why only five plates form the oral frames of coronates, blastoids and Lysocystites, whereas glyptocystitoids (except Rhombifera) have six oral frame plates; all glyptocystitoids have only five laterals. Hemicosmitoids arose by paedomorphic ambulacral reduction, but the paedomorphosis also affected the thecal plates and stem. Paedomorphosis poses special problems for cladistic character analysis, since the new characters often appear to be plesiomorphic.
Źródło:
Acta Palaeontologica Polonica; 2021, 66, 1; 41-62
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Afghanistan’s Civil War (1979-1989): Illegal and Failed Foreign Interventions
Autorzy:
Terry, Patrick C. R.
Powiązania:
https://bibliotekanauki.pl/articles/706873.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Nauk Prawnych PAN
Tematy:
Afghanistan
Soviet Union
USRR
civil war
Opis:
For about ten years now people in NATO member states have, on a daily basis, been confronted with the faltering attempts by their troops to create a semblance of stability in Afghanistan. It is now widely recognized that Afghanistan has become an intractable international problem. This article, however, focuses on previous attempts to impose solutions. Beginning in the late 1970s and continuing throughout the 1980s, the two Cold War superpowers, the USSR and the USA, intervened in Afghanistan’s affairs. In this article the legality, under international law, of those efforts is examined. This requires an extensive analysis of international law as applicable to external interventions in civil wars. It will be demonstrated that neither the USSR’s invasion of Afghanistan, nor the USA’s massive support of the Afghan rebels, was reconcilable with international law. Considering the fact that these ill-advised interventions in Afghanistan backfired on both superpowers, they constitute a good object lesson to demonstrate that the prohibition of external interventions in civil wars not only reflects what international law demands, but is also simple common sense. Recent interventions in Bahrain and Libya are also briefly examined as to their legality, and this examination includes projections whether the unsatisfactory results of the Afghanistan interventions will be replicated there.
Źródło:
Polish Yearbook of International Law; 2011, 31; 107-164
0554-498X
Pojawia się w:
Polish Yearbook of International Law
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Star Coloring of Subcubic Graphs
Autorzy:
Karthick, T.
Subramanian, C.R.
Powiązania:
https://bibliotekanauki.pl/articles/30146582.pdf
Data publikacji:
2013-05-01
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
vertex coloring
star coloring
subcubic graphs
Opis:
A star coloring of an undirected graph G is a coloring of the vertices of G such that (i) no two adjacent vertices receive the same color, and (ii) no path on 4 vertices is bi-colored. The star chromatic number of G, χs(G), is the minimum number of colors needed to star color G. In this paper, we show that if a graph G is either non-regular subcubic or cubic with girth at least 6, then χs(G) ≤ 6, and the bound can be realized in linear time.
Źródło:
Discussiones Mathematicae Graph Theory; 2013, 33, 2; 373-385
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Induced acyclic tournaments in random digraphs: Sharp concentration, thresholds and algorithms
Autorzy:
Dutta, Kunal
Subramanian, C.R.
Powiązania:
https://bibliotekanauki.pl/articles/31232000.pdf
Data publikacji:
2014-08-01
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
random digraphs
tournaments
concentration
thresholds
algorithms
Opis:
Given a simple directed graph $D = (V,A)$, let the size of the largest induced acyclic tournament be denoted by $mat(D)$. Let $D ∈ \mathcal{D}(n, p)$ (with $p = p(n)$) be a random instance, obtained by randomly orienting each edge of a random graph drawn from $\mathcal{G}(n, 2p)$. We show that $mat(D)$ is asymptotically almost surely (a.a.s.) one of only 2 possible values, namely either $b^\ast$ or $b^\ast + 1$, where $b^\ast = ⌊2(log_rn) + 0.5⌋$ and $r = p^{−1}$. It is also shown that if, asymptotically, $2(log_rn) + 1$ is not within a distance of $w(n)//(ln n)$ (for any sufficiently slow $w(n) → ∞$) from an integer, then $mat(D)$ is $⌊2(log_rn) + 1⌋$ a.a.s. As a consequence, it is shown that $mat(D)$ is 1-point concentrated for all $n$ belonging to a subset of positive integers of density 1 if $p$ is independent of $n$. It is also shown that there are functions $p = p(n)$ for which $mat(D)$ is provably not concentrated in a single value. We also establish thresholds (on $p$) for the existence of induced acyclic tournaments of size i which are sharp for $i = i(n) → ∞$. We also analyze a polynomial time heuristic and show that it produces a solution whose size is at least $log_rn + Θ(\sqrt{log_rn})$. Our results are valid as long as $p ≥ 1//n$. All of these results also carry over (with some slight changes) to a related model which allows 2-cycles.
Źródło:
Discussiones Mathematicae Graph Theory; 2014, 34, 3; 467-495
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Intersection Dimension and Graph Invariants
Autorzy:
Aravind, N.R.
Subramanian, C.R.
Powiązania:
https://bibliotekanauki.pl/articles/32083820.pdf
Data publikacji:
2021-02-01
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
circular dimension
dimensional properties
forbidden-subgraph colorings
Opis:
We show that the intersection dimension of graphs with respect to several hereditary properties can be bounded as a function of the maximum degree. As an interesting special case, we show that the circular dimension of a graph with maximum degree Δ is at most \(O\Big(\Delta\frac{log\Delta}{log log\Delta}\Big)\). It is also shown that permutation dimension of any graph is at most $\Delta(log \Delta)^{1+o(1)}$. We also obtain bounds on intersection dimension in terms of treewidth.
Źródło:
Discussiones Mathematicae Graph Theory; 2021, 41, 1; 153-166
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Recurrent neural identification and control of a continuous bioprocess via first and second order learning
Autorzy:
Baruch, I.
Mariaca-Gaspar, C. R.
Powiązania:
https://bibliotekanauki.pl/articles/385133.pdf
Data publikacji:
2010
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
backpropagation learning
direct adaptive neural control
indirect adaptive sliding mode control
Kalman filter recurrent neural network identifier
Levenberg-Marquardt learning
Opis:
This paper applies a new Kalman Filter Recurrent Neural Network (KFRNN) topology and a recursive Levenberg-Mar quardt (L-M) learning algorithm capable to estimate para meters and states of highly nonlinear unknown plant in noisy environment. The proposed KFRNN identifier, learned by the Backpropagation and L-M learning algorithm, was incorporated in a direct and indirect adaptive neural con trol schemes. The proposed control schemes were applied for real-time recurrent neural identification and control of a continuous stirred tank bioreactor model, where fast convergence, noise filtering and low mean squared error of reference tracking were achieved.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2010, 4, 4; 37-52
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of sewage sludge biogas fermentation with different temperatures and addition of maize silage
Porównanie wydajności biogazowej osadów ściekowych, w tym z dodatkiem kiszonki z kukurydzy w różnych temperaturach
Autorzy:
Carmona, P. C. R.
Dach, J.
Powiązania:
https://bibliotekanauki.pl/articles/357151.pdf
Data publikacji:
2015
Wydawca:
Politechnika Śląska
Tematy:
biogaz
osad ściekowy
kiszonka z kukurydzy
fermentacja mezofilowa
fermentacja termofilowa
biogas
sewage sludge
maize silage
fermentation
mesophilic
thermophilic
Opis:
Kiszonka z kukurydzy jest podstawowym surowcem wykorzystywanym w polskich biogazowniach. Jednak ze względu na coraz wyższe ceny tego substratu oraz wahania cen zielonych certyfikatów, koniecznym staje się poszukiwanie różnych substratów do produkcji biogazu. Z drugiej strony, duża ilość osadu wyprodukowanego w oczyszczalniach ścieków, tworzy poważny problem dla środowiska w Polsce. Stosowanie osadów ściekowych jako źródła energii odnawialnej może zmniejszyć ilość składowanych osadów i poprawić bezpieczeństwo środowiska. Problemem podczas beztlenowej fermentacji osadu ściekowego jest konieczność wystąpienia odpowiedniego stosunku C:N na poziomie 20-30. Dlatego ważne jest aby dodać do osadów innych, bogatych w węgiel materiałów. Przemawia również za tym fakt iż sam osad nie jest wydajnym substratem do produkcji biogazu. Zastosowanie ko-substratów pomoże maksymalnie wykorzystać potencjał fermentacyjny, reguluje kinetykę fermentacji metanowej poprzez poprawę stosunku C:N, zwiększa wydajność i opłacalność ekonomiczną procesu. Celem pracy było znalezienie synergii pomiędzy osadami ściekowymi oraz kiszonką z kukurydzy w dwóch różnych temperaturach: 39ºC (zakres mezofilowy) i 55ºC (zakres termofilowy).
Maize silage is the primary feedstock utilized in biogas plants in Poland. However, due to the increasingly high price of that substrate and the volatile prices of green certificates, it is necessary to search for different substrates for the biogas production. On the other hand, the large amount of sewage sludge produced in wastewater treatment plants creates an important environmental problem in Poland. The use of sewage sludge as a source of renewable energy reduces the amount of stored sludge and improves environmental safety. The problem during anaerobic digestion of sewage sludge is to provide a suitable C:N ratio in the range 20-30. Therefore, it is important to add to the sludge substances rich in carbon. It is because the sludge itself is an inefficient substrate in terms of biogas production. The use of co-substrates ensures maximum use of the potential of the digester, regulates the kinetics of methane fermentation by improving the C:N ratio, increasing its efficiency and economic viability. The aim of this paper is to find synergy between sewage sludge and maize silage in two different temperatures: 39ºC (mesophilic range) and 55ºC (thermophilic range).
Źródło:
Archiwum Gospodarki Odpadami i Ochrony Środowiska; 2015, 17, 3; 61-72
1733-4381
Pojawia się w:
Archiwum Gospodarki Odpadami i Ochrony Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Delineation of EMS-induced genetic variability in some agronomic traits in mungbean, Vigna radiata (L.) Wilczek.
Autorzy:
Singh, Rupinder
Agarwal, M.
Kole, C. R.
Powiązania:
https://bibliotekanauki.pl/articles/2199155.pdf
Data publikacji:
2008-06-22
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
EMS
genetic variability
Mungbean
Vigna radiata
Opis:
The investigation involved treatment of pre-soaked seeds (11h) of a mungbean cutivar, PUSA 9072 with five doses of ethyl methane suphonate (EMS) at 0.1, 0.25, 0.5, 0.75 and 1% for 4hr under dark. Observation on field grown mutagenized population with regard to 14 agronomic characters evidenced for induction of the variability in the M1 generation itself. The CV values of the traits for mutagenised population were stupendously higher for most of the test characters to the tune of 57% cases as compared to the untreated (control) plants...
Źródło:
Plant Breeding and Seed Science; 2008, 57; 21-24
1429-3862
2083-599X
Pojawia się w:
Plant Breeding and Seed Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dehydrofreezing of fruit using direct osmosis as concentration process
Zamrażanie owoców częściowo odwodnionych przez bezpośrednią osmozę
Autorzy:
Pinnavaia, G.
Dallarosa, M.
Lerici, C.R.
Powiązania:
https://bibliotekanauki.pl/articles/1399330.pdf
Data publikacji:
1988
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Opis:
Proces zamrażania w stanie częściowego odwodnienia (ang. dehydrofreezing) obejmuje częściowe osuszenie produktu przed mrożeniem. Niższa zawartość wody w produkcie podczas mrożenia daje następujące korzyści: - niższe zużycie energii na jednostkę świeżego produktu w czasie etapu mrożenia i późniejszego składowania, - obniżenie punktu krioskopowego, zmniejszenie ilości wody wymrażanej i wzrost szybkości mrożenia i rozmrażania. Bezpośrednia osmoza była przebadana jako technika odwodnieniowa dla wielu rodzajów owoców. Uzyskano ponadto następujące korzyści: - obniżenie zapotrzebowania na energię w procesie suszenia, - wzrost ogólnej zawartości składników suchej masy w produkcie z utrzymaniem konsystencji. - pobranie cukrów z syropu, lepsze zachowanie aromatu i lepsze zachowanie barwy, - obniżenie kwasowości i polepszenie właściwości organoleptycznych, - obniżenie skłonności do enzymatycznego brunatnienia.
Źródło:
Acta Alimentaria Polonica; 1988, 14(38), 1; 51-57
0137-1495
Pojawia się w:
Acta Alimentaria Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Osteological correlates for quadrupedality in ornithischian dinosaurs
Autorzy:
Maidment, S.C.R.
Barrett, P.M.
Powiązania:
https://bibliotekanauki.pl/articles/20234.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
The evolution of quadrupedality from bipedal ancestors is an exceptionally rare transition in tetrapod evolution, but it has occurred several times within the herbivorous dinosaur clade Ornithischia. Stegosauria, Ankylosauria, and Ceratopsidae are all uncontroversially quadrupedal, while basal ornithischians and basal ornithopods are uncontroversially bipedal. However, stance in iguanodontian ornithopods, including the hadrosaurs, and in non-ceratopsid ceratopsians is debated because robust osteological correlates of quadrupedality have not been identified. We examine a suite of characteristics that have been previously proposed as osteological correlates for bipedality or quadrupedality in dinosaurs. These include both discrete anatomical features, which we assess as correlates for quadrupedality using character optimization onto a composite cladogram, and proportional ratios, which we assess as correlates by reconstructing nodal ancestral states using squared-change parsimony, followed by optimization. We also examine the correlation of these features with body size. An anterolateral process on the proximal ulna, hoof-shaped manual unguals, a transversely broadened ilium, a reduced fourth trochanter and a femur longer than the tibia are found to be robust correlates of quadrupedality in ornithischian dinosaurs. Along the ceratopsid “stem” lineage, quadrupedal characters were acquired in a stepwise fashion, with forelimb characters developing prior to changes in the hind limb. In contrast, iguanodontid ornithopods display a mosaic of character states, indicating varying degrees of facultative quadrupedality that probably arose for a variety of different reasons. Hadrosaurs are found to possess all character states associated with quadrupedality and were probably predominantly quadrupedal. In general, quadrupedal ornithischians do not appear to have been constrained by their bipedal ancestry to a particular order of character acquisition.
Źródło:
Acta Palaeontologica Polonica; 2014, 59, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Genetic diversity of Blastocystis spp. in the human population of the Olsztyn area
Autorzy:
Lepczynska, M.
Dzika, E.
Stensvold, C.R.
Powiązania:
https://bibliotekanauki.pl/articles/5729.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Parazytologiczne
Tematy:
genetic diversity
Blastocystis
enteric protist
host
human population
Olsztyn region
Źródło:
Annals of Parasitology; 2016, 62, Suppl.
0043-5163
Pojawia się w:
Annals of Parasitology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Use of direct osmosis as fruit and vegetables dehydration
Wykorzystanie bezpośredniej osmozy w procesie suszenia owoców i warzyw
Autorzy:
Lerici, C.R.
Mastrocola, D.
Nicoli, M.C.
Powiązania:
https://bibliotekanauki.pl/articles/1399282.pdf
Data publikacji:
1988
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Opis:
Bezpośrednia osmoza jest procesem zagęszczania bez odparowania. Zachodzi ona w kawałkach żywności zanurzonej w roztworze hypertonicznym. Ponieważ roztwór ten wykazuje wyższe ciśnienie osmotyczne i wskutek tego niższą aktywność wody (aw) pomiędzy roztworem i żywnością powstają siły usuwające wodę, gdyż naturalna błona komórkowa działa jak półprzepuszczalna membrana. Owoce i warzywa były częściowo odwodnione przez zanurzenie w syropie skrobiowym kukurydzianym (70 Bx), w temperaturze pokojowej (25°C) i w wysokiej (powyżej 70°C). Mierzono ubytek wody, przyrost suchej masy i obniżenie aktywności wody w próbkach w stosunku do czasu suszenia. Bezpośrednia osmoza wykorzystywana była jako metoda wstępnego suszenia przed suszeniem powietrznym. Uzyskane wyniki wskazują, że produkty takie miały smak słodki, nie kwaśny i lepszą teksturę, barwę i zapach. Zastosowanie osmozy w wysokiej temperaturze przez krótki czas pozwala na uzyskanie łącznego efektu blanszowania i suszenia.
Źródło:
Acta Alimentaria Polonica; 1988, 14(38), 1; 35-40
0137-1495
Pojawia się w:
Acta Alimentaria Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Convective flow of hydromagnetic couple stress fluid with varying heating through vertical channel
Autorzy:
Makhalemele, C. R.
Rundora, L.
Adesanya, S. O.
Powiązania:
https://bibliotekanauki.pl/articles/1839878.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
pole magnetyczne
płyn nieściśliwy
wymiana ciepła
induced magnetic field
couple stresses
vertical channel
varying heating
Opis:
This article addresses the impact of magnetic field induction on the buoyancy-induced oscillatory flow of couple stress fluid with varying heating. Modelled equations for the incompressible fluid are coupled and nonlinear due to the inclusion of viscous heating and thermal effect on the fluid density. Approximate solutions are constructed and coded on a symbolic package to ease the computational complexity. Graphical representations of the symbolic solutions are presented with detailed explanations. Results of the present computation show that the effect of induced magnetic field on the oscillatory flow and heat transfer is significant and cannot be neglected.
Źródło:
International Journal of Applied Mechanics and Engineering; 2021, 26, 2; 107-127
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessing the Interplay Between the Shoulders and Low Back During Manual Patient Handling Techniques in a Nursing Setting
Autorzy:
Belbeck, A.
Cudlip, A. C.
Dickerson, C. R.
Powiązania:
https://bibliotekanauki.pl/articles/90188.pdf
Data publikacji:
2014
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
nursing
electromyography
shoulder
low back
ergonomics
ergonomia
personel pielęgniarski
techniki podnoszenia pacjentów
plecy
Opis:
The purpose of this research was to quantify shoulder demands during freestyle manual patient handling (MPH) tasks and determine whether approaches intended to prevent low back injury increased shoulder demands. Twenty females completed 5 MPH tasks found commonly in hospital settings before and after a training session using current workplace MPH guidelines. Most normalized muscle activity indices and ratings of perceived exertion decreased following training at both the low back and shoulders, but were more pronounced at the low back. There was little evidence to suggest that mechanical demands were transferred from the low back to the shoulders following the training session. The study generally supports continued use of the recommended MPH techniques, but indicates that several tasks generate high muscular demands and should be avoided if possible.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2014, 20, 1; 127-137
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of the Acoustic Suitability of an Open Plan Office Based on STI and DL2 Simulations
Autorzy:
Passero, C. R. M.
Zannin, P. H. T.
Powiązania:
https://bibliotekanauki.pl/articles/178137.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
open plan offices
acoustic evaluation
acoustic improvement
Opis:
Many business offices around the world are organized as open plan offices. Therefore, studies about the acoustic comfort of the people who work in them have become increasingly important. The focus of this work is the acoustic evaluation of an open plan office combining several architectural characteristics and levels of ambient noise. This evaluation was performed through a computational model calibrated from a real office. The rate of spatial decay of sound pressure levels per distance doubling (DL2) and the speech transmission index (STI) were simulated for the acoustic evaluation of the office, allowing for the determination of the radius of distraction (rD). These parameters were simulated for 6 situations using different floor and ceiling covering materials and inserting or withdrawing screens between workstations. In addition, STI and rD were simulated under two conditions of ambient noise. The results indicated that the DL2 and rD are adequate acoustic parameters for the acoustic evaluation and improvement of an open plan office. The DL2 was strongly influenced by the presence or absence of screens between workstations and by the ceiling covering material. The rD was more sensitive to changes in ambient noise.
Źródło:
Archives of Acoustics; 2012, 37, 2; 237-243
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mixed convective flow of unsteady hydromagnetic couple stress fluid through a vertical channel filled with porous medium
Autorzy:
Makhalemele, C. R.
Rundora, L.
Adesanya, S. O.
Powiązania:
https://bibliotekanauki.pl/articles/1839697.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
konwekcja mieszana
magnetohydrodynamika
przepływ oscylacyjny
couple stress fluid
mixed convection
magnetohydrodynamics
oscillatory flow
Opis:
In this paper, the mixed convective flow of an electrically conducting, viscous incompressible couple stress fluid through a vertical channel filled with a saturated porous medium has been investigated. The fluid is assumed to be driven by both buoyancy force and oscillatory pressure gradient parallel to the channel plates. A uniform magnetic field of strength 0B is imposed transverse to the channel boundaries. The temperature of the right channel plate is assumed to vary periodically, and the temperature difference between the plates is high enough to induce radiative heat transfer. Under these assumptions, the equations governing the two-dimensional couple stress fluid flow are formulated and exact solutions of the velocity and the temperature fields are obtained. The effects of radiation, Hall current, porous medium permeability and other various flow parameters on the flow and heat transfer are presented graphically and discussed extensively.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 4; 148-161
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Acoustic Emission Signals and Damage Analysis During the Tensile Test on Al8011 Hybrid Composites by Stir Casting Method
Autorzy:
Kannan, C. R.
Suresh, S.
Navaneetha Krishnan, M.
Powiązania:
https://bibliotekanauki.pl/articles/2203742.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Al8011
stir casting
acoustic emission
tensile
corrosion
Opis:
Metal network compounds have primary properties. The use of lightweight and low vitality is a testament to the growing interest in the automotive industry. Aluminum alloys, due to their advanced physical, mechanical and tribological properties, have become a highly emerging material for a variety of industrial applications and the importance of efficient material selection is explained. In this paper, an Al8011 hybrid metal matrix composite is developed through the stir casting process. The different weight proportions of B4C (3%, 6%, 9% & 12%) and fixed proportions of 2% MoS2 have been used. Composite developed are subjected to mechanical properties evaluation and seawater corrosion studies following standard procedures. To study the porosity of the composite samples, theoretical density and actual density are calculated. An acoustic emission system-assisted tensile test is carried out to report the strength of the composite. From this experimental method, adding reinforcement can increase the tensile strength and hardness of the composites. Under sea water, the increase in reinforcement found an increase in corrosion resistance. Fractured surfaces were perused using SEM and EDS analysis.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 1; 223--235
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Field Quantification of Physical Exposures of Police Officers in Vehicle Operation
Autorzy:
McKinnon, C. D.
Callaghan, J. P.
Dickerson, C. R.
Powiązania:
https://bibliotekanauki.pl/articles/90976.pdf
Data publikacji:
2011
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
police officers
driving
activity characterization
mobile data terminal
Opis:
Mobile police officers perform many of their daily duties in their vehicles. Combined workspace inflexibility and prolonged driving create potential musculoskeletal injury risks. Limited research exists that quantitatively describes postural and load exposures associated with mobile police work. The purpose of this study was to characterize officer activity during a typical workday and identify opportunities for ergonomic intervention. Digital video of traffic officers (N = 10) was used to classify postures according to work activity. Cumulative time in 10 activities was calculated, and a time-history of driver activity documented. Most (55.5 ± 13.4%) time was out of the vehicle, and 22.3 ± 10.5% was spent in single-arm driving. On paper documentation and mobile data terminal use were identified as in-car activities that may benefit from targeted interventions. The primary contribution of this study is characterization of daily mobile police activity and the identification of possible intervention strategies to mitigate physical exposure levels.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2011, 17, 1; 61-68
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Od Toussainta L’Ouverture’a do Fidela Castro
From Toussaint L’Ouverture to Fidel Castro
Autorzy:
James, C.L.R.
Powiązania:
https://bibliotekanauki.pl/articles/1012454.pdf
Data publikacji:
2016-06-15
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
Toussaint L’Overture
Karaiby
rewolucja
négritude
emancypacja
Fidel Castro
niewolnictwo
plantacja
czarny nacjonalizm
Opis:
Niniejszy tekst stanowi dodatek do klasycznej już analizy rewolucji na Haiti C.L.R. Jamesa. Autor w tym apendyksie do Black Jacobins porusza kwestię dwóch konstytutywnych jego zdaniem elementów dla gospodarki i społeczeństwa karaibskich wysp – uprawy trzciny cukrowej i czarnego niewolnictwa. Zagadnienia te są podejmowane w kontekście ruchów emancypacyjnych i rewolucyjnych od Toussainta L’Ouverture’a po Fidela Castro.
Źródło:
Praktyka Teoretyczna; 2016, 20, 2; 112-140
2081-8130
Pojawia się w:
Praktyka Teoretyczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Injury Risk in Behind Armor Blunt Thoracic Trauma
Autorzy:
Bass, C. R.
Salzar, R. S.
Lucas, C. R.
Davis, M.
Donnellan, L.
Folk, B.
Sanderson, E.
Waclawik, S.
Powiązania:
https://bibliotekanauki.pl/articles/90978.pdf
Data publikacji:
2006
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
blunt trauma
Thora
armor
ballistic
zagrożenia zdrowia
zagrożenia mechaniczne
uszkodzenie kości
profilaktyka
środki ochrony indywidualnej
służba wojskowa
kamizelka kuloodporna
Opis:
First responders and military personnel are particularly susceptible to behind armor blunt thoracic trauma in occupational scenarios. The objective of this study was to develop an armored thorax injury risk criterion for short duration ballistic impacts. 9 cadavers and 2 anthropomorphic test dummies (AUSMAN and NIJ 0101.04 surrogate) were tested over a range of velocities encompassing low severity impacts, medium severity impacts, and high severity impacts based upon risk of sternal fracture. Thoracic injuries ranged from minor skin abrasions (abbreviated injury scale [AIS] 1) to severe sternal fractures (AIS 3+) and were well correlated with impact velocity and bone mineral density. 8 male cadavers were used in the injury risk criterion development. A 50% risk of AIS 3+ injury corresponded to a peak impact force of 24,900 ± 1,400 N. The AUSMAN impact force correlated strongly with impact velocity. Recommendations to improve the biofidelity of the AUSMAN include implementing more realistic viscera and decreasing the skin thickness.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2006, 12, 4; 429-442
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Two new stegosaur specimens from the Upper Jurassic Morrison Formation of Montana, USA
Autorzy:
Woodruff, D.C.
Trexler, D.
Maidment, S.C.R.
Powiązania:
https://bibliotekanauki.pl/articles/21465.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
Two partial skeletons from Montana represent the northernmost occurrences of Stegosauria within North America. One of these specimens represents the northernmost dinosaur fossil ever recovered from the Morrison Formation. Consisting of fragmentary cranial and postcranial remains, these specimens are contributing to our knowledge of the record and distribution of dinosaurs within the Morrison Formation from Montana. While the stegosaurs of the Morrison Formation consist of Alcovasaurus, Hesperosaurus, and Stegosaurus, the only positively identified stegosaur from Montana thus far is Hesperosaurus. Unfortunately, neither of these new specimens exhibit diagnostic autapomorphies. Nonetheless, these specimens are important data points due to their geographic significance, and some aspects of their morphologies are striking. In one specimen, the teeth express a high degree of wear usually unobserved within this clade—potentially illuminating the progression of the chewing motion in derived stegosaurs. Other morphologies, though not histologically examined in this analysis, have the potential to be important indicators for maturational inferences. In suite with other specimens from the northern extent of the formation, these specimens contribute to the ongoing discussion that body size may be latitudinally significant for stegosaurs—an intriguing geographical hypothesis which further emphasizes that size is not an undeviating proxy for maturity in dinosaurs.
Źródło:
Acta Palaeontologica Polonica; 2019, 64, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of diabetes and diabetes complications on hand dexterity and quality of life – a quantitative study
Autorzy:
Lewko, J.
Sadowska, E.
Sierzantowicz, R.
Lewko, K.
Lukaszuk, C.R.
Powiązania:
https://bibliotekanauki.pl/articles/3561.pdf
Data publikacji:
2019
Wydawca:
Instytut Medycyny Wsi
Źródło:
Journal of Pre-Clinical and Clinical Research; 2019, 13, 2
1898-2395
Pojawia się w:
Journal of Pre-Clinical and Clinical Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Life cycle extension of mobile phones: an exploration with focus on the end-consumer
Autorzy:
Penners, Odette
Semeijn, Janjaap
van Riel, Allard C.R.
Lambrechts, Wim
Powiązania:
https://bibliotekanauki.pl/articles/14450797.pdf
Data publikacji:
2018-12-22
Wydawca:
Wyższa Szkoła Bankowa we Wrocławiu
Tematy:
end of life
e-waste
mobile phones
recycling
WEEE
Opis:
Aim: All mobile phones will eventually become obsolete and should be collected and recycled in order to recover their high content of both dangerous and valuable materials. End-consumers play a key role in these processes as the collection and recycle systems cannot work properly without their contribution. Therefore, this exploratory study investigates how Dutch end-consumers can be stimulated to return their used mobile phones. Design / Research methods: the factors influencing consumers’ propensity to return and recycle obsolete mobile phones are examined. The results are based on a survey conducted among end-consumers of mobile phones in the Netherlands. Conclusions / findings: There is significant recycling potential as the majority of used mobile phones are simply kept at home. Keeping a used phone as a spare phone and being afraid of privacy disclosures are indicated as main reasons for not taking used phones to a recycling point. Originality / value of the article: The findings indicate that personal satisfaction from recycling and knowledge or awareness of the potential dangers from not properly returning play a crucial role in influencing the propensity.
Źródło:
Central European Review of Economics and Management; 2018, 2, 4; 7-37
2543-9472
Pojawia się w:
Central European Review of Economics and Management
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The analysis of environmental and human impacts of using Strong Alkaline Water for cooling during machining
Autorzy:
Da Silva, P.
Tanabe, I.
Junior, D. C. R.
Takahashi, S.
Powiązania:
https://bibliotekanauki.pl/articles/99481.pdf
Data publikacji:
2018
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
eco-friendly
strong alkaline water
emission
cooling
Opis:
An eco-friendly manufacturing approach is important for the environment. Enhancing machining performances is not only required to improve product’s quality, time saving, and reduces costs; it is also contributed to the environmental protection efforts. Cooling is important aspect for obtaining this purpose. Therefore the benefits of Strong Alkaline Water (SAW) cooling method was assessed and compared with conventional wet cutting method. An experiment was performed at Nagaoka University of Technology machining centre. Three machine tools including a milling machine, a drilling machine and a turning machine were used. The study shows that using SAW for cooling is far more efficient than conventional cooling method. It reduces annual global warming potential by 72.95%, acidification potential 98.18%, ozone depletion potential 99.6%, smog formation potential 85.71% and human toxicity potential 42.86% compare with conventional method. The study concludes that besides inhibiting corrosion, prolonging tool life, improving surface roughness of final cutting and reducing energy usage, strong alkaline water cooling is an environmentally friendly approach and has positive impact on human health.
Źródło:
Journal of Machine Engineering; 2018, 18, 1; 45-60
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of Crosstalk into High Resistivity Silicon Substrate on the RF Performance of SOI MOSFET
Autorzy:
Ali, K. B.
Neve, C. R.
Gharsallah, A.
Raskin, J. P.
Powiązania:
https://bibliotekanauki.pl/articles/308378.pdf
Data publikacji:
2010
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
crosstalk
high resistivity Si
mixing products
passivation layer
polysilicon
Opis:
Crosstalk propagation through silicon substrate is a serious limiting factor on the performance of the RF devices and circuits. In this work, substrate crosstalk into high resistivity silicon substrate is experimentally analyzed and the impact on the RF behavior of silicon-on-insulator (SOI) MOS transistors is discussed. The injection of a 10 V peak-to-peak single tone noise signal at a frequency of 3 MHz ( fnoise) generates two sideband tones of ?56 dBm separated by fnoise from the RF output signal of a partially depleted SOI MOSFET at 1 GHz and 4.1 dBm. The efficiency of the introduction of a trap-rich polysilicon layer located underneath the buried oxide (BOX) of the high resistivity (HR) SOI wafer in the reduction of the sideband noise tones is demonstrated. An equivalent circuit to model and analyze the generation of these sideband noise tones is proposed.
Źródło:
Journal of Telecommunications and Information Technology; 2010, 4; 93-100
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quality management and customer satisfaction in a tourist destination, a structural equation analysis
Zarządzanie jakością i satysfakcja klienta w miejscu przeznaczenia turystycznego, analiza równoważenia strukturalnego
Autorzy:
Perez, C. R.
Garcia, V. G.
Sanchez, R. A.
Martinez, V. R.
Powiązania:
https://bibliotekanauki.pl/articles/405510.pdf
Data publikacji:
2017
Wydawca:
Politechnika Częstochowska
Tematy:
quality management
customer satisfaction
tourist destination
tourism
structural equation analysis
zarządzanie jakością
zadowolenie klienta
destynacja turystyczna
turystyka
analiza równania strukturalnego
Opis:
The paper is based on the premise that customers aspire to achieve maximum satisfaction of the products or services they buy so that knowledge of customer satisfaction enables an organization organized according to provide quality services assuming that levels higher quality leads to higher levels of customer satisfaction. Its empirical research was carried out in the tourist destination Holguín, northeastern Cuba, including more than 2,000 tourists and 70 tourism service providers, and was designed to provide information on the relationship between the level of tourist satisfaction and the variables of quality assurance in the destination. By means of the compilation and analysis of the obtained data a model of structural equations was constructed to visualize the nature of the relations that they were intended to demonstrate. The obtained results indicate that there are relations between the variables that assure the quality and the satisfaction of the customer leaving identified the possibilities of improvement.
Artykuł opiera się na założeniu, że klienci dążą do osiągnięcia maksymalnej satysfakcji z kupowanych produktów lub usług, dzięki czemu wiedza o zadowoleniu klienta pozwala zorganizować organizację zgodnie z dostarczaniem wysokiej jakości usług, zakładając, że wyższa jakość prowadzi do wyższego zadowolenia klienta. Niniejsze badanie empiryczne przeprowadzono w miejscowości turystycznej Holguín w północno-wschodniej Kubie, wzięło w nich udział ponad 2000 turystów i 70 usługodawców turystycznych, a jego celem było dostarczenie informacji na temat związku między poziomem zadowolenia turystów a poziomem jakości świadczonych usług za pomocą kompilacji i analizy uzyskanych danych skonstruowano model równań strukturalnych, celem zwizualizowania charakteru relacji, które zamierzano zademonstrować. Uzyskane wyniki wskazują, że istnieją powiązania między zmiennymi, które zapewniają jakość i satysfakcję klienta, pozostawiając zidentyfikowane możliwości poprawy.
Źródło:
Polish Journal of Management Studies; 2017, 16, 1; 175-186
2081-7452
Pojawia się w:
Polish Journal of Management Studies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Growth performance and haematology of broiler chickens fed diets with graded sweet potato (Ipomoea batatas) leaf meals
Autorzy:
Unigwe, C. R.
Ononogbu, C. E.
Adejuyigbe, A. D.
Abonyi, F. O.
Powiązania:
https://bibliotekanauki.pl/articles/1188082.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Broilers
FCR
growth
haematology
PER
sweet potato leaf meal
Opis:
A total of 60 Russ 2011 two weeks old broiler chicks with an average weight of 215.33+4.55g were fed with diets compounded with sweet potato leaves (SPL) for 56 days. The diets consist of T1 (0% SPL), T2 (5% SPL), T3 (10% SPL) and T4 (15% SPL). The proximate composition of the SPL was determined in the laboratory. The birds were randomly allocated to four treatments using completely randomized design (CRD). Each treatment was subdivided into three replicates of five chicks each. At the end of the experiment, all data collected were subjected to one way analysis of variance and difference in means was separated using Duncan’s New Multiple Range Test. The results showed no significant difference (p>0.05) in the average body weight gain, feed intake, feed conversion ratio (FCR) and protein efficiency ratio (PER). However, birds on T2 (32.77g) had the best daily body weight gain followed by T4 (30.36g), T3 (30.06g) and T1 (29.21g) while in terms of daily feed intake, T4 (98.20g) consumed most followed by T2 (98.17g) and T3 (96.59g) whereas, T1 (92.38g) consumed the least feed. The birds on T2 (3.00) demonstrated the best FCR followed by T1 (3.16), T3 (3.21) and T4 (3.23). Also T1 (1.59) showed the best PER closely followed by T1 (1.53), T3 (1.46) and T4 (1.43). There was, however, a significant difference (p<0.05) in Hb concentration when T2 (11.62g/dl) and T3 (12.48g/dl) were compared with T1 (10.34g/dl) and T4 (10.21g/dl). In the PCV, a statistical difference (p<0.05) also was observed between T1 (24.73%) and others (T2 (28.18%), T3 (28.97%)and T4 (27.14%)) while similar trend (p<0.05) was seen in the RBC count when T4 (9.72x106/ul) was compared with T1 (10.21 x106/ul), T2 (10.81x106/ul) and T3 (11.43x106/ul) and no significant difference (p>0.05) among all the treatments with respect to WBC (T1 (21.23x103/ul), T2 (19.18x103/ul), T3 (21.26x103/ul) and T4 (22.63x103/ul)). Although the haematological parameters fell within normal physiological ranges, there was a gradual increase in these values as the inclusion levels progressed till T3 (10% inclusion) and then a decrease. It is therefore recommended that inclusion of SPL up to 5% in the diet of broilers is good for enhanced body weight gain, FCR and PER and up to 10% for enhanced haematological parameters.
Źródło:
World Scientific News; 2016, 56; 45-55
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Impact of Mobile Data Terminal Use on Posture and Low-Back Discomfort When Combined With Simulated Prolonged Driving in Police Cruisers
Autorzy:
Gruevski, K. M.
McKinnon, C. D.
Dickerson, C. R.
Callaghan, J. P.
Powiązania:
https://bibliotekanauki.pl/articles/91020.pdf
Data publikacji:
2013
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
occupational driving
low-back discomfort
mobile data terminals
police officers
pozycja przy pracy
kierowcy i maszyniści
nerwoból okolicy grzbietowej
dyskomfort
policjant
kierowcy zawodowi
Opis:
The introduction of mobile computing within a constrained vehicle environment has led to changes in the task demands of occupational groups such as professional drivers and law enforcement officers. The purpose of this study was to examine how mobile data terminal (MDT) use interacts with prolonged driving to induce postural changes or low-back discomfort. Eighteen participants (9 male, 9 female) completed two 120-min simulated driving sessions. Time-varying lumbar spine and pelvis postures, seat pan interface pressures and ratings of perceived discomfort were recorded at 15-min intervals. The introduction of a computer interface decreased pelvic posterior rotation by an average of 15° with respect to upright standing and increased peak average discomfort in the neck (5.9 mm), left shoulder (6.8 mm), midback (10.9 mm), low back (10.6 mm) and pelvis (11.5 mm) compared to driving alone. The incorporation of mobile computing warrants consideration in the design of vehicle work environments.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2013, 19, 3; 415-422
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Understanding the Effect of Speed of Exertion on Isokinetic Strength Using a Multiaxial Dynamometer
Autorzy:
Nimbarte, A. D.
Aghazadeh, F.
Bogolu, S. C. R.
Rajulu, S. L.
Powiązania:
https://bibliotekanauki.pl/articles/90640.pdf
Data publikacji:
2009
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
isokinetic strength
fatigue
repetitions
Opis:
In this study a multiaxial isokinetic dynamometer was used to measure strength during various upper-body isokinetic exertions. Ten male participants performed 7 different upper-body isokinetic exertions. In addition, to evaluate the effect of speed on strength, each participant performed sitting pull exertions at the speed of 0.026, 0.130, and 0.260 m/s. Average isokinetic strength increased from 236.6 ± 39.1 to 291.8 ± 65.8 N with the initial increase in speed from 0.026 to 0.130 m/s. The average isokinetic strength decreased to 276.7 ± 87.2 N with a further increase in speed to 0.260 m/s. The curve between isokinetic strength and speed followed a bell-shaped curve (fitted with the Gaussian function, R2 = .9). The results of this study could be useful in deciding on the work pace of various manual material handling tasks requiring maximal and/or near maximal exertions.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2009, 15, 3; 255-263
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A reassessment of the purported ankylosaurian dinosaur Bienosaurus lufengensis from the Lower Lufeng Formation of Yunnan, China
Autorzy:
Raven, T.J.
Barrett, P.M.
Xu, X.
Maidment, S.C.R.
Powiązania:
https://bibliotekanauki.pl/articles/21669.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
The earliest definitive ornithischian dinosaurs are from the Early Jurassic and are rare components of early dinosaur faunas. The Lower Lufeng Formation (Hettangian–Sinemurian) of Yunnan Province, China, has yielded a diverse Early Jurassic terrestrial vertebrate fauna. This includes several incomplete specimens have been referred to Ornithischia, including the type specimen of the thyreophoran “Tatisaurus” and other generically indeterminate material. The highly fragmentary Lufeng ornithischian Bienosaurus lufengensis was described briefly in 2001 and identified as an ankylosaurian dinosaur. Recent studies have cast doubt on this hypothesis, however, and given that the referral of Bienosaurus to Ankylosauria would result in an extensive ghost-lineage extending between it and the first definitive eurypodans (ankylosaurs + stegosaurs) in the Middle Jurassic, the holotype specimen is re-examined and re-described. We identify Bienosaurus as a probable thyreophoran dinosaur, although the fragmentary nature of the material and the absence of autapomorphies means that the specimen should be regarded as a nomen dubium.
Źródło:
Acta Palaeontologica Polonica; 2019, 64, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanical Spectroscopy of MgB2 Containing SiC
Spektroskopia mechaniczna MgB2 zawierającego SiC
Autorzy:
Silva, M. R.
Silva, L. B. S.
Rodriques Jr., D.
Grandini, C. R.
Powiązania:
https://bibliotekanauki.pl/articles/355880.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
mechanical spectroscopy
internal friction
anelasticity
MgB2
SiC
spektroskopia mechaniczna
tarcie wewnętrzne
właściwości anelastyczne
Opis:
The compound magnesium diboride (MgB2) has been well-known since the 1950s; however, its superconducting properties were unknown. Intrinsic characteristics of MgB2 make this material a promising candidate for technological applications, although the low value of the irreversibility field and the decrease in critical current density with the increase in the magnetic field considerably reduce its utility. The present work aimed to study the effect of carbon-based doping on anelastic properties of MgB2 as measured by mechanical spectroscopy. The samples were prepared by using the powder-intube method. The samples were made with 5, 7.5, and 10 wt.% of silicon carbide (SiC). The results reveal complex mechanical loss spectra caused by the interaction between point defects and surface defects in the crystalline lattice of MgB2.
Dwuborek związek magnezu (MgBV) jest znany od 1950 roku; jednak jego właściwości nadprzewodzące były nieznane. Swoiste cechy MgB2 czynią ten materiał obiecującym kandydatem do zastosowań technicznych, jednak niskie wartości nieodwracalnego pola i zmniejszenie krytycznej gęstości prądu ze wzrostem pola magnetycznego znacznie zmniejszają jego użyteczność. Celem pracy było zbadanie wpływu domieszkowania związkiem węgla na anelastyczne właściwości MgB2 mierzone metodą spektroskopii mechanicznej. Próbki zostały przygotowane za pomocą metody powder-in-tube (PIT). Wytworzono próbki o zawartości 5, 7.5 i 10 % wag. węglika krzemu (SiC). Wyniki pokazują złożone widma strat mechanicznych powodowanych przez wzajemne oddziaływanie pomiędzy defektami punktowymi i defektami powierzchniowymi w sieci krystalicznej MgB2.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 4; 3083-3086
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Internal Friction and Microstructure of Ti and Ti-Mo Alloys Containing Oxygen
Autorzy:
Martins Jr, J. R. S.
Araújo, R. O.
Nogueira, R. A.
Grandini, C. R.
Powiązania:
https://bibliotekanauki.pl/articles/351840.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
mechanical spectroscopy
anelasticity
internal friction
Ti-Mo alloys
interstitials
biomaterials
Opis:
Ti-Mo alloys are promising materials for use as biomaterials, because these alloys have excellent corrosion resistance and a good combination of mechanical properties such as fatigue, low elastic modulus, hardness, and wear resistance. The objective of this paper was to study the effect of heavy interstitial atoms on anelastic properties of Ti-Mo alloys using mechanical spectroscopy. The internal friction and Young’s modulus were measured as a function of temperature using dynamic mechanical analyser. The internal friction spectra were brought about by relaxation processes attributed to shortrange stress induced reorientation of interstitial and substitutional complexes in solid solution. It is suggested that the nature of the relaxing entities can be worked out in further research on Ti-Mo single crystals.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 25-30
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badanie wydajności biogazowej substratów z biogazowni rolniczej w Zakładzie Doświadczalnym Uniwersytetu Przyrodniczego w Przybrodzie k. Poznania
Testing the biogas substrate efficiency from the Experimental Farm’s of Poznan University of Life Sciences in Przybroda biogas plant
Autorzy:
Lewicki, A.
Dach, J.
Czekała, W.
Janczak, D.
Cieślik, M.
Witaszek, K.
Carmona, P. C. R.
Powiązania:
https://bibliotekanauki.pl/articles/357403.pdf
Data publikacji:
2014
Wydawca:
Politechnika Śląska
Tematy:
biogaz
biogazownia
wydajność biogazowa
biogas
biogas plant
biogas efficiency
Opis:
Kierunek energetyczny Europy został wyznaczony już kilka lat temu. Prawidłowa gospodarka odpadami nie jest już tylko modą zamożnych krajów europejskich - stała się ona wymogiem prawnym. Przetwarzanie bioodpadów na biogaz jest jedną z najefektywniejszych technologii zapewniających uzyskanie „zielonej” energii oraz polepszenie stanu środowiska. Budowa małych i tanich biogazowni rolniczych, takich jak prowadzona aktualnie w gospodarstwie doświadczalnym UP w Przybrodzie jest jedną z najlepszych dróg dla rozpowszechnienia tej technologii waloryzacji bioodpadów. Celem niniejszej pracy było zbadanie wydajności biogazowej substratów dostępnych w Zakładzie Doświadczalnym poznańskiego Uniwersytetu Przyrodniczego w Przybrodzie (gnojowica świńska i bydlęca, kiszonka kukurydziana oraz wysłodki buraczane). Kompleksowa analiza laboratoryjna wykazała nie tylko pozytywny bilans ekonomiczny, ale także bardzo korzystny wpływ, badanej technologii zagospodarowania substratów, na środowisko.
An energetic development of Europe has been planned few years ago. Proper waste management is not just a trend of western European countries - it is a law. Production of biogas from bio-waste is one of the most effective technologies, assuring the production of green energy and improvements of the environment condition. Building of small and cheap biogas plants – as the one built at the Experimental Farm of Life Science University in Przybroda (250kWe) is one of the best ways to spread this technology and valorization of bio-waste. The aim of this study was to determine biogas efficiency of substrates available Experimental Farm (pig slurry, caw slurry, maize silage) Research run at the Institute of Biosystems Engineering, was one of main factors which decided about rector of University agreement to start a biogas plant project. Complex laboratory analysis proved not only very positive economic balance but also very good influence, checked technology of waste management into environment.
Źródło:
Archiwum Gospodarki Odpadami i Ochrony Środowiska; 2014, 16, 1; 27-30
1733-4381
Pojawia się w:
Archiwum Gospodarki Odpadami i Ochrony Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Medical students’ perceptions of people with disabilities
Autorzy:
Guzowski, A.
Kułak-Bejda, A.
Stelcer, B.
Jasiński, M.
Łukaszuk, C.R.
Cybulski, M.
Kułak, W.
Powiązania:
https://bibliotekanauki.pl/articles/1918400.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Medyczny w Białymstoku
Tematy:
Medical students
attitudes
people with disabilities
life satisfaction
empathy
Opis:
Introduction: Little is known about associations of attitudes of medical students towards people with disabilities and their life satisfaction and empathy. Purpose: To assess the social perception of people with disabilities by medical students. Materials and methods: The present study interviewed 451 medical students of the Medical University of Białystok regarding their perceptions of people with disabilities, especially in light of their own satisfaction with life and empathy. We used the following questionnaires: the original questionnaire about attitudes towards people with disabilities, The Satisfaction with Life Scale (SWLS), and Empathy Understanding Questionnaire (KRE). Results: Attitudes towards people with disabilities people were generally positive. Almost 40% of respondents expressed a willingness to help for people with disabilities. In general, disabled people do not have full access to all fields of social (63.4%) and professional (63.2%) life. At the same time, disabled people tend to marry (84.9%), have children (82.1%), work (88.2%), and drive cars (76.1%). Respondents were convinced that contact with a disabled person teaches ways to help others (42.1%), and in fact 58.6% of respondents reported having decided to participate with helping the disabled. The average life satisfaction of the students was 22.7 ± 5.3 which indicates that the respondents are satisfied with their lives. The empathy level of respondents was 66.97 points ± 2.98, which indicates average level of empathy. Conclusions: This study shows that students’ perception of people with disabilities depends upon how the students viewed disabled people’s, life satisfaction and empathy.
Źródło:
Progress in Health Sciences; 2016, 6(2); 125-131
2083-1617
Pojawia się w:
Progress in Health Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Knowledge, attitude and practice on exposure to Bisphenol A among dental surgeons in Southern India
Autorzy:
Kumar, H.A.
Soans, C.R.
Murali, P.S.
Ravi, R.S.
Shashidhar, K.
Shersha, S.
Powiązania:
https://bibliotekanauki.pl/articles/2082822.pdf
Data publikacji:
2021
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Tematy:
knowledge
attitude
practice
Bisphenol A
composite
dental surgeons
Opis:
Background. Bisphenol A (BPA) is a product in the manufacture of Bis-GMA, which is commonly used in dentistry, and is known to have a number of adverse effects. Objectives. The aim of this study is to evaluate to assess the knowledge, attitude and practice based on exposure and handling of BPA containing materials among dental surgeons for better understanding about the level of care rendered to the patients. Material and methods. A questionnaire survey was conducted on 400 dental surgeons in Southern India. The questionnaire consisted of 20 objective type questions out of which ten questions assessed knowledge and five questions assessed the attitude and five questions to understand the practice related measures taken by the dentist. The data collected were analysed using SPSS version 23. Results. A total of 402 responses were collected for this online questionnaire survey over a period of 2 months. It was found that females showed higher knowledge and attitude towards exposure to BPA which was statistically significant when compared to males. It showed that dentists with more than 20 years of practice had a higher level of knowledge. Though most of the groups agreed fairly on safety practice to be undertaken related to BPA exposure in their clinics, the ones with experience more than 20 years displayed the least positive attitude and dentists with 6-10 years of practice had the least positive behaviour among all. Conclusions. In spite of having a good knowledge regarding the harmful effects of BPA, dental surgeons are not very cautious while using materials containing them on a regular basis. Therefore, there is a need to enhance the awareness with the help of Continuing Dental Education programs or proper instructions on the packaging.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2021, 72, 4; 443-451
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Porównanie tlenowej i beztlenowej technologii zagospodarowania obornika świńskiego w różnych warunkach temperatury otoczenia
Comparison of the aerobic and anaerobic technologies of pig manure management in different ambient temperature conditions
Autorzy:
Czekała, W.
Dach, J.
Janczak, D.
Lewicki, A.
Carmona, P. C. R.
Witaszek, K.
Mazur, R.
Powiązania:
https://bibliotekanauki.pl/articles/357198.pdf
Data publikacji:
2014
Wydawca:
Politechnika Śląska
Tematy:
obornik świński
odpady rolnicze
kompostowanie
ochrona środowiska
pig manure
agricultural waste
composting
environmental protection
Opis:
Jednym z priorytetów wynikających z członkostwa Polski w UE jest zwiększenie wymagań z zakresu rolnictwa. Ma to związek między innymi z problemami związanymi z ochroną środowiska, a dotyczącymi właściwego zagospodarowania nawozów naturalnych, w tym i obornika. Jedną z metod takiego zagospodarowania może być kompostowanie. Stąd celem pracy było określenie możliwości kompostowania obornika pochodzącego od trzody chlewnej w małych i średnich gospodarstwach rolnych oraz opracowanie technologii możliwej do wdrożenia w przeciętnym gospodarstwie rolnym posiadającym podstawowe wyposażenie w techniczne środki produkcji, jak ciągnik, ładowacz czołowy oraz rozrzutnik obornika. W tym celu badania obejmowały kompostowanie obornika świńskiego oraz jego składowanie w warunkach beztlenowych. Wykazano, że metoda kompostowania obornika była korzystniejsza od jego składowania i może znaleźć zastosowanie w małych i średnich gospodarstwach rolnych.
One of the priorities related with Poland accession to the European Union was an increase of the of the requirements in the field of environmental protection. One of the biggest problems bounded with environmental protection is the management of the animal faeces and manure including. Such technology is composting of the animal faeces. The aim of this study was to determine the possibilities of pig manure composting in small and medium-size farms. It was assumed that the developed technology should be possible to implement in an average farm equipped with the basic technical production means (tractor, loader, manure spreader). In this study it has been investigated and compared the composting process with anaerobic storage of pig manure from animals kept in deep litter system. Obtained results clearly showed that composting process is more favorable from the point of view of environmental protection, and can be done in a small medium farm having basic technical means.
Źródło:
Archiwum Gospodarki Odpadami i Ochrony Środowiska; 2014, 16, 2; 19-32
1733-4381
Pojawia się w:
Archiwum Gospodarki Odpadami i Ochrony Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania separacji na frakcje stałą i ciekłą gnojowicy i pulpy pofermentacyjnej
Research on slurry and digestate pulp separation on the solid and liquid fraction
Autorzy:
Cieślik, M.
Lewicki, A.
Carmona, P. C. R.
Czekała, W.
Janczak, D.
Witaszek, K.
Dach, J.
Powiązania:
https://bibliotekanauki.pl/articles/357356.pdf
Data publikacji:
2014
Wydawca:
Politechnika Śląska
Tematy:
pulpa
biogazownia
separacja
gnojowica
nawożenie
gospodarka odpadami
digested pulp
biogas plant
solid liquid separation
slurry
fertilization
waste management
Opis:
Separacja na frakcję stałą i ciekłą oraz późniejsze wykorzystanie frakcji stałej na cele energetyczne (pelet) lub nawozowe może być jednym z najefektywniejszych metod zagospodarowania gnojowicy lub pulpy pofermentacyjnej. Celem pracy było określenie efektywności separacji gnojowicy i pulpy pofermentacyjnej oraz analiza składu fizykochemicznego frakcji stałej odseparowanej na sitach różnej wielkości. Analizie poddano także uzyskany po przejściu przez mikrosita odciek z gnojowicy i pofermentu. Stwierdzono duże różnice w rozkładzie frakcji i zawartości w nich materii organicznej oraz popiołu pomiędzy frakcjami gnojowicy i różnymi rodzajami pulpy pofermentacyjnej. Stwierdzono, że jedynie pierwsza frakcja z gnojowicy jak i z pulpy pofermentacyjnej otrzymanej z fermentacji roślin zwierających dużą ilość organicznych materiałów trudno rozkładalnych może być brana pod uwagę jako substrat do produkcji peletów na cele energetyczne.
The separation on solid and liquid fraction and subsequent usage of a solid fraction for energy (pellets) or fertilizer aims can be one of he most effective ways of slurry and digestate management. The aim of this study was to determine the effectiveness of the separation of slurry and digestate pulp and analysis of the physico-chemical composition of the solid fraction separated on the strainers of different sizes. Also the slurry and digestate pulp effluent after passing the micro-strainers was analyzed. The results showed large differences in the fractions distribution and the content of organic matter between the slurry and particular types of the digestate pulp. It has been stated that only digestate pulp from the fermentation of the plants with large amount of hardly biodegradable materials (cellulose, lignin) can be considered as a substrate for the pellets production for energy purposes.
Źródło:
Archiwum Gospodarki Odpadami i Ochrony Środowiska; 2014, 16, 2; 43-48
1733-4381
Pojawia się w:
Archiwum Gospodarki Odpadami i Ochrony Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First record of a Jurassic mammal [?'Peramura'] from Ethiopia
Autorzy:
Clemens, W A
Goodwin, M.B.
Hutchison, J.H.
Schaff, C.R.
Wood, C.B.
Colbert, M.W.
Powiązania:
https://bibliotekanauki.pl/articles/21748.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Ethiopia
tooth fragment
first record
mammal
Peramura
Mammalia
Jurassic
Mugher Mudstone
paleontology
Opis:
The first record of Mesozoic mammals in Ethiopia is a fragment of a lower mammalian molar discovered in residues left after acid dissociation of a small (ca. 4 kg) geological hand sample of a fine−grained bone bed in the lower part of the Mugher Mudstone exposed in the valley of the Jema River. This bone bed is part of a series of estuarine to fluvial deposits that are thought to be of Late Jurassic (Tithonian) age. The fragment preserves the trigonid of a molar; the distal part of its crown is missing. Morphological characters of the trigonid indicate the specimen (JEM−5/21) documents the presence of a mammal with a dentition at either a derived pretribosphenic or primitive tribosphenic grade of evolution. Absence of a well developed basal cingulid around the mesial end of the crown argues against phylogenetic relationships to the australosphenidans. Loss of the distal portion of the crown removed characters critical for determining its grade of evolution. The working hypothesis that JEM−5/21 represents a “peramuran” is advanced for testing. Hypotheses that it represents a mammal with a more derived grade of molar evolution or a previously unknown group of mammals cannot be excluded. JEM−5/21 establishes the presence of mammals in Ethiopia during the Late Jurassic, and its discovery identifies a fossil locality warranting thorough future exploration.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of air temperature on forecasting the start of Cupressaceae pollen type in Ponferrada [Leon, Spain]
Autorzy:
Fuertes-Rodriguez, C R
Gonzales-Parrado, Z.
Vega-Maray, A.M.
Valencia-Barrera, R.M.
Fernandez-Gonzales, D.
Powiązania:
https://bibliotekanauki.pl/articles/50902.pdf
Data publikacji:
2007
Wydawca:
Instytut Medycyny Wsi
Tematy:
Ponferrada
woody plant
pollen
aerobiology
heat requirement
Leon
Cupressaceae
forecast
chilling requirement
Spain
dormancy
Opis:
In order to survive periods of adverse cold climatic conditions, plant requirements are satisfi ed by means of physiological adaptations to prevent cells from freezing. Thus, the growth of woody plants in temperate regions slows down and they enter into a physiological state called dormancy. In order to identify the chilling and heat requirements to overcome the dormancy period of Cupressaceae pollen type in the south of Europe, we have carried out our study with aerobiological data from a 10-year (1996- 2005) period in Ponferrada, León (Spain). For the chilling requirements the best result was with a threshold temperature of 7.1ºC and an average of 927 CH. Calculation of heat requirements was carried out with maximum temperature, with 490 growth degree days (GDD) needed, with a threshold temperature of 0ºC. We have used the 2002-2003, 2003- 2004 and 2004-2005 periods in order to determine the real validity of the model. We have not used these years in developing the models. The dates predicted differ in only a few days from those observed: in 2002-2003 there was a difference of 11 days, in 2003-2004 predicted and observed dates were the same, but in 2004-2005 the difference obtained was of 43 days.
Źródło:
Annals of Agricultural and Environmental Medicine; 2007, 14, 2
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Occupational, Personal and Psychosocial Resources for Preventing Persistent Low Back Pain
Autorzy:
Melloh, M.
Salathe, C. R.
Elfering, A.
Kaser, A.
Barz, T.
Aghayev, E.
Roder, C.
Theis, J. C.
Powiązania:
https://bibliotekanauki.pl/articles/90429.pdf
Data publikacji:
2013
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
occupational
health outcomes
low back pain
predictors
prognosis
prospective cohort study
badania naukowe
nerwoból okolicy grzbietowej
zagrożenia zdrowia
profilaktyka
czynnik ludzki
czynniki psychospołeczne
czynniki zawodowe
czynniki personalne
Opis:
The aim of this prospective cohort study was to identify modifiable protective factors of the progression of acute/subacute low back pain (LBP) to the persistent state at an early stage to reduce the socioeconomic burden of persistent LBP. Patients attending a health practitioner for acute/subacute LBP were assessed at baseline addressing occupational, personal and psychosocial factors, and followed up over 12 weeks. Pearson correlations were calculated between these baseline factors and the presence of nonpersistent LBP at 12-week follow-up. For those factors found to be significant, multivariate logistic regression analyses were performed. The final 3-predictor model included job satisfaction, mental health and social support. The accuracy of the model was 72%, with 81% of nonpersistent and 60% of persistent LBP patients correctly identified. Further research is necessary to confirm the role of different types of social support regarding their prognostic influence on the development of persistent LBP.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2013, 19, 1; 29-40
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fermentacja metanowa pomiotu kurzego jako alternatywa i przyjazna środowisku technologia jego zagospodarowania
Methane fermentation of the poultry manure as an alternative and environmentally friendly technology of its management
Autorzy:
Carmona, P. C. R.
Witaszek, K.
Janczak, D.
Czekała, W.
Lewicki, A.
Dach, J.
Pilarski, K.
Mazur, R.
Powiązania:
https://bibliotekanauki.pl/articles/357362.pdf
Data publikacji:
2014
Wydawca:
Politechnika Śląska
Tematy:
obornik kurzy
kiszonka z kukurydzy
biogaz
fermentacja
poultry manure
maize silage
biogas
fermentation
Opis:
Polska jest jednym z czołowych producentów drobiu w Europie. Roczne ilości odchodów drobiowych w skali kraju to blisko 4 mln ton. Tradycyjna gospodarka pomiotem drobiowym powoduje silną uciążliwość odorową oraz może być groźna dla środowiska z uwagi na wymywanie dużych ilości azotu, związków mineralnych i przeniesienie licznych patogenów. Dodatkowo składowane w pryzmach odchody drobiowe emitują duże ilości metanu oraz amoniaku. Fermentacja metanowa może być skuteczną technologią eliminacji wspomnianych wcześniej uciążliwości. Okazuje się jednak, że mimo rozwoju biogazowni rolniczych w Europie, nie istnieje wydajna technologia pozwalająca na fermentację pomiotu. Celem pracy było określenie możliwości fermentacji metanowej pomiotu w mieszance z najpopularniejszym wsadem do biogazowni czyli kiszonką z kukurydzy. Uzyskane wyniki dowodzą, że fermentacja pomiotu bez domieszek daje niską produkcję biogazu na poziomie 340 m3/t s.m, co jest ponad 2-krotnie mniejszym wynikiem niż wydajność kiszonki z kukurydzy. Jednak dodatek kiszonki do fermentacji pomiotu pozwala na znaczący wzrost wydajności biogazowej i zwiększenie efektywności procesu.
Poland is one of the leading producers of poultry in Europe. The annual quantities of the poultry manure in the national scale are close to 4 million tons. The traditional economy of poultry manure causes strong odor nuisance and may be dangerous to the environment due to the leaching of the large amounts of nitrogen, minerals and transfer of many pathogens. Additionally, poultry manure stored in the piles emits large amounts of methane and ammonia. The methane fermentation can be an effective technology of elimination of the before mentioned nuisance. However it turns out, that despite the development of agricultural biogas plants in Europe, there is no efficient technology that enables manure fermentation. The aim of this study was to determine the possibilities of methane fermentation of the poultry manure in the mixture of the most popular input for biogas plants that is maize silage. The obtained results show that fermentation of the poultry manure without any additives gives low production of biogas at the level of 340 m3/t of dry matter, which is the result almost twice lower than the efficiency of maize silage. However, the silage addition to the poultry manure fermentation allows for a significant increase of biogas productivity and growth of the process efficiency.
Źródło:
Archiwum Gospodarki Odpadami i Ochrony Środowiska; 2014, 16, 1; 21-26
1733-4381
Pojawia się w:
Archiwum Gospodarki Odpadami i Ochrony Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of neem leaf (Azadirachta indica) meal on growth performance and haematology of rabbits
Autorzy:
Unigwe, C. R.
Balogun, F. A.
Okorafor, U. P.
Odah, I. S.
Abonyi, F. O.
Olona, J. F.
Powiązania:
https://bibliotekanauki.pl/articles/1192593.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Rabbits
Neem leaf meal
growth performance
haematology
feed conversion ratio
Opis:
A ten-week experiment using twenty four (24) weaner rabbits (Chinchila x New Zealand White) aged 8 to 9 weeks with an average initial body weight of 431.20+0.74g were randomly allocated to four treatment diets of T1(control), T2(5% NLM), T3(10% NLM) and T4(15% NLM) in a completely randomized design. They were fed for 10 weeks during which data on growth and haematology were collected and analysed using analysis of variance (ANOVA) and means separated using Duncan Multiple Range Test. The results showed that the average total body weight gains were 739.60g (T1), 717.85g (T2), 740.18g (T3) and 729.45g (T4).There was no significant difference (p>0.05) when T1 and T3 as well as T2 and T4 were compared but significant (p<0.05) when T1 and T2 as well as T3 and T4 were compared. Also the average weekly feed intake showed that T1, T2, T3 and T4 consumed 313.91g, 313.24g, 312.48g and 314.69g respectively. However, there was significant difference (p<0.05) when all the treatments were compared in this respect. The feed conversion ratio (FCR) showed that T3 (4.22) was the best followed by T1 (4.24), T4 (4.31) and T2(4.36) with significant differences (p<0.05) among them except (p>0.05) between T1 and T3. The haematological indices showed that though all the parameters fell within the normal physiologic ranges, the PCV was 37.62% (T1), 38.42% (T2), 39.60% (T3) and 39.03% (T4) and when compared, were all significantly different (p<0.05) except (P>0.05) for T3 and T4 while the haemoglobin concentration showed that T1(13.47g/dl) was significantly different (p<0.05) from T2(14.18g/dl), T3(14.34g/dl), and T4(13.97g/dl). The white blood cell count showed that T3 (10.62 x109/L) had the highest value followed by T1 (10.12 x109/L), T4 (9.34 x109/L) and T2 (9.18 x109/L) with a significant difference (p<0.05) occurring when T1 and T3 were compared to T2 and T4 while the red blood cell counts indicated that T1 had the highest value of 4.92 x106/L followed by T3(4.89 x106/L), T2(4.73 x106/L) and T4(4.65 x106/L) without any significant difference among the treatments. All the values fell within the normal range. It is therefore recommended that inclusion of neem leaf meal in the diets of rabbits up to 10% is not detrimental since it improved feed conversion ratio (FCR), growth performance and had no negative effect on haematological values.
Źródło:
World Scientific News; 2016, 55; 51-62
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spatio-temporal variation of microphytoplankton in the upwelling system of the South-Eastern Arabian Sea during the summer monsoon of 2009
Autorzy:
Thomas, L.C.
Padmakumar, K.B.
Smitha, B.R.
Asha Devi, C.R.
Nandan, S.B.
Sanjeevan, V.N.
Powiązania:
https://bibliotekanauki.pl/articles/49085.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
Arabian Sea
upwelling
coastal water
phytoplankton
chlorophyll a
diatom
centric diatom
spatio-temporal variability
microphytoplankton
Chaetoceros
Źródło:
Oceanologia; 2013, 55, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evolution from the BCS to the Bose-Einstein Limit in a d-Wave Superconductor at T=0
Autorzy:
Borkowski, L. S.
Sá de Melo, C. A. R.
Powiązania:
https://bibliotekanauki.pl/articles/2027398.pdf
Data publikacji:
2001-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.20.-z
74.25.Gz
67.40.Db
Opis:
We study the evolution from BCS to Bose limit in a two-dimensional d-wave superconductor at zero temperature and low density of charge carriers within the mean-field theory. We examine single quasiparticle properties when particle density and attraction strength are varied. For sufficiently high interaction strength there is a critical density below which the system has a gap. The spectral and thermodynamic properties of the system do not evolve smoothly from the BCS-like to the Bose-like regime.
Źródło:
Acta Physica Polonica A; 2001, 99, 6; 691-698
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Response of coastal phytoplankton to upwelling induced hydrological changes in the Alappuzha mud bank region, Southwest coast of India
Autorzy:
Madhu, N.V.
Anil, P.
Meenu, P.
Gireeshkumar, T.R.
Muraleedharan, K.R.
Rehitha, T.V.
Dayana, M.
Vishal, C.R.
Powiązania:
https://bibliotekanauki.pl/articles/2078930.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
phytoplankton
hydrological change
coastal upwelling
chlorophyll a
algal bloom
mud bank
nearshore area
Alappuzha
India
Opis:
The response of phytoplankton community to the co-existing events of coastal upwelling and mud banks in the nearshore waters of Alappuzha (15 m depth), located in the southwest coast of India from April to November 2016, is described based on size-fractionated phytoplankton biomass (chlorophyll a), primary production and community composition. The study region exhibited well-distinct spatio-temporal hydrological changes because of the influence of wind-driven coastal upwelling, prevalent during the southwest monsoon (SWM) period. However, the formation of mud banks, in addition to coastal upwelling, was observed at station M2, which facilitated the substantial increase of water column turbidity and inorganic nutrients (ammonium, phosphate, and silicate) during and after the peak SWM period compared to the non-mud bank reference stations (M1 and M3). The prevailing hydrological changes were complemented the corresponding phytoplankton productivity patterns, in which profound domination of nanophytoplankton (2—20 μm) chlorophyll a and primary production was observed throughout the study region, irrespective of seasons. The SIMPER analysis, based on phytoplankton (mostly >20 μm) species composition data (microscopy), revealed the formation of certain characterizing species, mainly comprised of diatoms and dinoflagellates. The consistent predominance of the nanophytoplankton, established under variable hydrological scenarios, showed that the inorganic nutrient (specifically ammonium) availability was instrumental in defining the widespread growth of nanophytoplankton community compared to the prevailing light levels. The present study thus revealed that even the small-sized phytoplankton community could survive in the nutrient-enriched coastal waters, characterised by the co-existing upwelling and mud banks.
Źródło:
Oceanologia; 2021, 63, 2; 261-275
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Expression on hypoxia-inducible factor-1α in human tegumentary leishmaniosis caused by Leishmania braziliensis
Autorzy:
Rocha, F.J.S.
Pereira, C.L.D.
de Melo, F.L.
Soares, C.R.P.
Paz, S.T.
Giorgio, S.
Powiązania:
https://bibliotekanauki.pl/articles/6320.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Parazytologiczne
Źródło:
Annals of Parasitology; 2018, 64, 1
0043-5163
Pojawia się w:
Annals of Parasitology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nutrient uptake efficiency of five pistachio (Pistacia vera L.) varieties
Autorzy:
Aznarte-Mellado, C.
Sola-Campoy, P.J.
Robles, F.
Villasenor, J.G.
Rejon, C.R.
de la Herran, R.
Navajas-Perez, R.
Powiązania:
https://bibliotekanauki.pl/articles/1189813.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie / Polskie Towarzystwo Magnezologiczne im. Prof. Juliana Aleksandrowicza
Tematy:
nutrient uptake
pistachio nut
Pistacia vera
nutrient content
edible fruit
Opis:
Pistacia vera L., whose edible fruit is the pistachio, is an economically important crop. It is cultivated worldwide and over 50 different varieties have been described attending to morphological and phenological characteristics. The selection of a suitable cultivar may affect the profitability of the orchards, and thus requires careful consideration for any given region. The type and concentration of nutrients taken up by the plant affect its development and eventually the quality and quantity of the fruits. It is a matter of discussion whether all varieties have the same capacity to absorb nutrients. In order to clarify this aspect, in this study the efficiency of nutrient uptake has been assessed for five pistachio varieties: three males (M38, G1, and Mateur), and two females (Batoury, and Joley), by measuring the concentration of 30 chemical elements in leaves by Inductively Coupled Plasma (ICP) and C/N micro-elemental analyses. Data were subjected to a non-parametric Friedman test, using a series of Wilcoxon Rank Sum test with a Bonferroni correction as post hocs. Our findings demonstrate that all these varieties have an equal uptake capacity for Al, Cr, Cu, K, Li, Mn, Ni, Pb, S, Sr, Ti, Tl, Zn, N, B, Fe, Mg, Na, and V. No differences related to the gender of the plants were detected. Only Mateur exhibited significantly higher levels of Ca and lower levels of C. Stock plants from an experimental plot were used as material. These plants are not used for productive purposes, and flowering and fruiting are partially restricted by removing potential nutrient-demanding structures. These findings support the contention that the presence/absence of such organs has more influence on the nutrient uptake than does the variety itself.
Źródło:
Journal of Elementology; 2016, 21, 1; 141-148
1644-2296
Pojawia się w:
Journal of Elementology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cosmic Airburst on Developing Allerød Substrates (Soils) in the Western Alps, Mt. Viso Area
Autorzy:
Mahaney, William C.
West, Allen
Milan, Alison
Krinsley, David H.
Somelar, Peeter
Schwartz, Stephane
Milner, Michael W.
Allen, Christopher C.R.
Powiązania:
https://bibliotekanauki.pl/articles/2025231.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Black Mat impact/airburst
Reconstructed soil at time of YDB
mid-LG-YD paleosol Sedimentary products of cosmic impact/glacial recession
Nauki o Ziemi
Opis:
Although much has been written about a cosmic impact event in the Western Alps of the Mt. Viso area, the event closely tied with the Younger Dryas Boundary (YDB) of 12.8 ka and onset of the Younger Dryas (YD), the affected land surface is considered to contain a similar black mat suite of sediment found on three continents. While work elsewhere has focused on recovered sediment from lake and ice cores, buried lacustrine/alluvial records, and surface glacial and paraglacial records, no one has traced a mountain morphosequence of deposits with the objective of investigating initial weathering/ soil morphogenesis that occurred in ice recessional deposits up to the YDB when the surface was subjected to intense heat, presumably, as hypothesized by Mahaney et al. (2016a) from a cosmic airburst. With the land surface rapidly free of ice following glacial retreat during the Bølling-Allerød interstadial, weathering processes ~13.5 to 12.8 ka led to weathering and soil morphogenesis in a slow progression as the land surface became free of ice. To determine the exposed land character in the mid- to late-Allerød, it is possible to utilize an inverted stratigraphic soil morphogenesis working backward in time, from known post-Little Ice Age (LIA) (i.e. time-zero) through LIA (~0.45 to ~0.10 ka), to at least the middle Neoglacial (~2 ka), to answer several questions. What were the likely soil profile states in existence at the end of the Allerød just prior to the cosmic impact/airburst (YDB)? Assuming these immature weathered regolith sections of the Late Allerød approximated the <1 ka old profiles seen today, and assuming the land surface was subjected to a hypothesized instant temperature burst from ambient to ~2200oC at ~12.8 ka, what would be the expected effect on the resident sediment? To test the mid-LG (YDB) to YD relationship we analyzed the paleosols in both suites of deposits – mid-LG to YD – to test that the airburst grains are restricted to Late Allerød paleosols and using relative-age-determination criteria, that the overlapping YD to mid-LG moraines are closely related in time. These are some of the questions about the black mat that we seek to answer with reference to sites in the upper Guil and Po rivers of the Mt. Viso area.
Źródło:
Studia Quaternaria; 2018, 35; 3-23
1641-5558
2300-0384
Pojawia się w:
Studia Quaternaria
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nutrient uptake efficiency of five pistachio (Pistacia vera L.) varieties
Autorzy:
Aznarte-Mellado, C.
Sola-Campoy, P.J.
Robles, F.
Villasenor, J.G.
Rejon, C.R.
de la Herran, R.
Navajas-Perez, R.
Powiązania:
https://bibliotekanauki.pl/articles/14870.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie / Polskie Towarzystwo Magnezologiczne im. Prof. Juliana Aleksandrowicza
Tematy:
nutrient uptake
pistachio nut
Pistacia vera
nutrient content
edible fruit
Opis:
Pistacia vera L., whose edible fruit is the pistachio, is an economically important crop. It is cultivated worldwide and over 50 different varieties have been described attending to morphological and phenological characteristics. The selection of a suitable cultivar may affect the profitability of the orchards, and thus requires careful consideration for any given region. The type and concentration of nutrients taken up by the plant affect its development and eventually the quality and quantity of the fruits. It is a matter of discussion whether all varieties have the same capacity to absorb nutrients. In order to clarify this aspect, in this study the efficiency of nutrient uptake has been assessed for five pistachio varieties: three males (M38, G1, and Mateur), and two females (Batoury, and Joley), by measuring the concentration of 30 chemical elements in leaves by Inductively Coupled Plasma (ICP) and C/N micro-elemental analyses. Data were subjected to a non-parametric Friedman test, using a series of Wilcoxon Rank Sum test with a Bonferroni correction as post hocs. Our findings demonstrate that all these varieties have an equal uptake capacity for Al, Cr, Cu, K, Li, Mn, Ni, Pb, S, Sr, Ti, Tl, Zn, N, B, Fe, Mg, Na, and V. No differences related to the gender of the plants were detected. Only Mateur exhibited significantly higher levels of Ca and lower levels of C. Stock plants from an experimental plot were used as material. These plants are not used for productive purposes, and flowering and fruiting are partially restricted by removing potential nutrient-demanding structures. These findings support the contention that the presence/absence of such organs has more influence on the nutrient uptake than does the variety itself.
Źródło:
Journal of Elementology; 2016, 21, 1
1644-2296
Pojawia się w:
Journal of Elementology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Railway industry roadmap in the state of Santa Catarina, Brazil
Roadmap para a indústria ferroviário do estado de Santa Catarina, Brasil
Autorzy:
Dias, A.
Da Silva, J. C.
Kagueiama, H. H.
Haddad, C. R.
Uriona, M. M.
Lezana, Á. G. R.
Juliatto, D. L.
Powiązania:
https://bibliotekanauki.pl/articles/374823.pdf
Data publikacji:
2015
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
technology
roadmapping
rail industry
technologia
mapa drogowa
przemysł kolejowy
branża kolejowa
Opis:
This article aims to identify the main requirements to strengthen the railroad industry in Santa Catarina by using technology roadmapping. The railway industry is composed of carriers, manufacturers, suppliers, operators, logistics, services and education. The survey aimed to provide guidelines for the Federation of the State of Santa Catarina Industry (FIESC) to develop its strategic plan for the next eight years. Based on the survey, the roadmap defined vision, mission, a list of key concepts, drivers and actions for the Federation to support the railway industry development, since this industrial sector is still economically unrepresented when compared to other sectors in Santa Catarina. The survey also pointed out there is a strong expansion program of the railway freight and railway transport for people in Brazil, both in government and private sectors.
Este artigo objetiva identificar os principais requisitos para fortalecer a indústria ferroviária em Santa Catarina (SC), por meio da aplicação do processo de technology roadmapping. A indústria ferroviária é composta por transportadores, fabricantes, fornecedores, operadores de logística, serviços e educação. A pesquisa objetivou fornecer orientações para a Federação das Indústrias de Santa Catarina (FIESC) com a finalidade de desenvolver um plano estratégico para os próximos oito anos. Baseando-se na pesquisa, definiram-se a visão, missão e uma lista de conceitos chaves, drivers e ações para que a FIESC apoiasse o desenvolvimento da indústria ferroviária, uma vez que esta é economicamente pouco representativa em comparação com outras indústrias no estado de SC. A pesquisa apontou que há forte expansão do transporte de cargas e pessoas no Brasil, tanto nos setores governamentais quanto nos setores privados.
Źródło:
Transport Problems; 2015, T. 10, z. spec.; 29-36
1896-0596
2300-861X
Pojawia się w:
Transport Problems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Deep-level defects in epitaxial 4H-SiC irradiated with low-energy electrons
Głębokie centra defektowe w warstwach epitaksjalnych 4H-SiC napromieniowanych elektronami o niskiej energii
Autorzy:
Kaminski, P.
Kozubal, M.
Caldwell, J. D.
Kew, K. K.
Van Mil, B. L.
Myers-Ward, R. L.
Eddy, C. R. jr.
Gaskill, D. K.
Powiązania:
https://bibliotekanauki.pl/articles/192318.pdf
Data publikacji:
2010
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Materiałów Elektronicznych
Tematy:
4H-SiC
DLTS
pułapka elektronowa
defekt punktowy
electron trap
point defects
Opis:
Deep level transient spectroscopy (DLTS) has been applied to study defect centers in the epitaxial layers of nitrogen-doped n-type 4H-SiC before and after the irradiation with a dose of 1.0x1017 cm-2 of 300-keV electrons. It is shown that the minority carrier lifetime in the as-grown epilayers is predominantly affected by the Z1/2 center concentration. The capture cross-section of the Z1/2 center for holes is found to be ˜ 6.0x10-14 cm2. We have tentatively attributed the center to the divacancy VCVSi formed by the nearest neighbor silicon and carbon vacancies located in different (h or k) lattice sites. The substantial increase in the Z1/2 center concentration induced by the low-energy electron irradiation is likely to be dependent on both the residual concentration of silicon vacancies and nitrogen concentration in the as-grown material. Four irradiation-induced deep electron traps with the activation energies of 0.71, 0.78, 1.04 and 1.33 eV have been revealed. The 0.71-eV trap, observed only in the epilayer with a higher nitrogen concentration of 4.0x1015 cm3, is provisionally identified with the complex defect involving a dicarbon interstitial and a nitrogen atom. The 0.78-eV and 1.04-eV traps are assigned to the carbon vacancy levels for VC (2-/-) and VC (-/0), respectively. The 1.33-eV trap is proposed to be related to the dicarbon interstitial.
Niestacjonarną spektroskopię pojemnościową (DLTS) zastosowano do badania centrów defektowych w domieszkowanych azotem warstwach epitaksjalnych 4H-SiC typu n przed oraz po napromieniowaniu dawką elektronów o energii 300 keV, równą 1,0x1017 cm3. Pokazano, że czas życia mniejszościowych nośników ładunku w warstwach nienapromieniowanych jest zależny głównie od koncentracji centrów Z1/2. Stwierdzono, że przekrój czynny na wychwyt dziur przez te centra wynosi ˜ 6x1014 cm2. W oparciu o dyskusję wyników badań przedstawionych w literaturze zaproponowano konfigurację atomową centrów Z1/2. Stwierdzono, że centra te są prawdopodobnie związane z lukami podwójnymi VCVSi, utworzonymi przez znajdujące się w najbliższym sąsiedztwie luki węglowe (VC) i luki krzemowe (VSi) zlokalizowane odpowiednio w węzłach h i k lub k i h sieci krystalicznej 4H-SiC. Otrzymane wyniki wskazują, że przyrost koncentracji centrów Z1/2 wywołany napromieniowaniem elektronami o niskiej energii zależny jest zarówno od koncentracji luk krzemowych, jak i od koncentracji azotu w materiale wyjściowym. Wykryto cztery pułapki elektronowe charakteryzujące się energią aktywacji 0,71 eV, 0,78 eV, 1,04 eV i 1,33 eV powstałe w wyniku napromieniowania. Pułapki o energii aktywacji 0,71 eV, które wykryto tylko w warstwie epitaksjalnej o większej koncentracji azotu równej 4x1015 cm-3, są prawdopodobnie związane z kompleksami złożonymi z atomów azotu i dwóch międzywęzłowych atomów węgla. Pułapki o energii aktywacji 0,78 eV i 1,04 eV przypisano lukom węglowym znajdującym się odpowiednio w dwóch różnych stanach ładunkowych VC(2-/-) i VC(-/0). Pułapki o energii aktywacji 1,33 są prawdopodobnie związane z aglomeratami złożonymi z dwóch międzywęzłowych atomów węgla.
Źródło:
Materiały Elektroniczne; 2010, T. 38, nr 3-4, 3-4; 26-34
0209-0058
Pojawia się w:
Materiały Elektroniczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical Properties and Microstructure of InGaN Grown by Molecular Beam Epitaxy
Autorzy:
Böttcher, T.
Einfeldt, S.
Figge, S.
Kirchner, V.
Hommel, D.
Selke, H.
Ryder, P. L.
Bertram, F.
Riemann, T.
Christen, J.
Lunz, U.
Becker, C. R.
Powiązania:
https://bibliotekanauki.pl/articles/1969025.pdf
Data publikacji:
1998-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.35.Dv
68.65.+g
78.20.-e
78.55.-m
78.55.Cr
Opis:
The luminescence of In$\text{}_{x}$Ga$\text{}_{1-x}$N is studied for thick epitaxial layers and quantum wells. Using spatially resolved cathodoluminescence spectroscopy the commonly observed broad integral photoluminescence spectra were found to result from spectral and lateral inhomogeneous emission across the samples. Moreover, the integral photoluminescence and absorption spectra show different temperature dependences. The effects can be explained assuming fluctuations of the composition associated with a variation of the band gap.
Źródło:
Acta Physica Polonica A; 1998, 94, 2; 260-264
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis and glycosyl composition of the exopolysaccharide isolated from submerged fermentation of Ganoderma lucidum CG144
Autorzy:
Rubel, R.
Freire dos Santos, L.
Stutz Dalla Santa, H.
Porto de Souza Vandenberghe, L.
Wojciechowski, A.L.
de Carvalho, J.C.
Habu, S.
Destefanis Vitola, F.M.
Augur, C.
Soccol, C.R.
Powiązania:
https://bibliotekanauki.pl/articles/56735.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
glycosyl composition
exopolysaccharide
isolation
submerged fermentation
Ganoderma lucidum
heteroglycan
herbal medicine
Chinese medicine
Opis:
The evaluation of glycosyl composition is an essential step to guide future research designs applied in bioactivity. In the same way, the unexplored potential bioactivity of exopolysaccharide from Ganoderma lucidum is huge. Therefore, this study investigated the glycosyl composition of the exopolysaccharide isolated from submerged fermentation of G. lucidum to serve as guide for future studies on bioactivity. Glycosyl content and composition were evaluated by combined GC/ MS of the TMS derivatives of the monosaccharide methyl glycosides produced from the sample by acidic methanolysis. Glycosyl composition analysis showed that the dominant carbohydrate component in all samples of exopolysaccharide isolated from submerged fermentation of G. lucidum CG 144 was glucose (58.1%), mannose (26.6%) and galactose (12.5%) which can be referred to as heteroglycan. These results suggest that this Ganoderma exopolysaccharide may be a new immunomodulatory agent.
Źródło:
Acta Societatis Botanicorum Poloniae; 2014, 83, 3
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Step Forward Towards Exploring Nutritional and Biological Potential of Mushrooms: A Case Study of Calocybe gambosa (Fr.) Donk Wild Growing in Serbia
Autorzy:
Petrović, Joavana
Fernandes, Angela
Stojković, Dejan
Soković, Marina
Barros, Liliana
Ferreira, Isabel C.F.R.
Shekhar, Aditya
Glamoclija, Jasmina
Powiązania:
https://bibliotekanauki.pl/articles/2019468.pdf
Data publikacji:
2022-03-01
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
C. gambosa
nutritional value
biological activity
chemical characterization
food ingredient
Opis:
Edible mushrooms have been appreciated globally for their organoleptic, nutritional and chemical properties. In the present study, fruiting body of Calocybe gambosa, wild growing in Serbia, has been chemically characterized (content of macronutrients, soluble sugars, tocopherols, fatty and organic acids) and its bioactive (antimicrobial and antioxidant) properties were evaluated. The results obtained suggest that this mushroom is a source of carbohydrates and proteins (72 g/100 g dry weight (dw) and 16 g/100 g dw, respectively), with a low fat content (1.5 g/100 g dw). Sugar analysis revealed the presence of trehalose (3.82 g/100 g dw) and mannitol (0.22 g/100 g dw). Tocopherol composition revealed the presence of α-tocopherol (7.8 μg/100 g dw), while fatty acid analysis revealed the presence of 24 fatty acids with the prevalence of polyunsaturated fatty acids. Amongst organic acids, oxalic, quinic, malic, citric and fumaric acid were detected (2.8 g/100 g dw, 1.45 g/100 g dw, 11.3 g/100 g dw, 1.3 g/100 g dw, 0.08 g/100 g dw, respectively). Comprehensive antioxidant activity analysis (reducing power, DPPH radical scavenging activity, β-carotene/linoleate and TBARS assays) indicate that the mushroom is a perspective antioxidant source, whereas its antimicrobial potential turned out to be moderate. Nevertheless, at a sub-inhibitory level, the methanolic extract disrupted cell-to-cell communication using Pseudomonas aeruginosa PAO1 as a model system. Finally, enrichment of oatmeal cookies with C. gambosa flakes not only improved their nutritional value, but was praised among the participants in sensory evaluation test, indicating that along with results of chemical composition and biological activity, this mushroom has a potential to be regarded as functional food.
Źródło:
Polish Journal of Food and Nutrition Sciences; 2022, 72, 1; 17-26
1230-0322
2083-6007
Pojawia się w:
Polish Journal of Food and Nutrition Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Control of natural mycobiota in maize grains by ultraviolet (UVC) irradiation
Zwalczanie naturalnych mikobiot w ziarnie kukurydzy za pomocą promieniowania ultrafioletowego (UVC)
Autorzy:
Paez, C.L.R.
Reyes, M.C.P.
Aguilar, C.H.
Pacheco, F.A.D.
Martinez, E.M.
Orea, A.C.
Bonilla, J.L.L.
Powiązania:
https://bibliotekanauki.pl/articles/36667.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
natural mycobiota
mycobiota
fungi
control
maize grain
Zea mays
ultraviolet irradiation
Opis:
The effect of UV-C light as a means of control of natural mycobiota of grains of maize (Zea mays L.) hybrids “San Juan” and ”H-159” (productive cycle, 2009) was investigated. UV-C lamps of 15 W were used and the exposure times applied were 0, 5, 10, 15, 20, 25 and 30 min. The experiment was established in the randomised complete block design with eight and four replicates. The unit pilot was 50 grains. For the determination of mycobiota the agar plate test was used, after disinfection of the grains with sodium hypochlorite diluted to 3% for 1 min. Differences (P ≤ 0.001, P ≤ 0.05) between treatments were found, the best treatments being those of 30 and 10 min, observing reductions of 42.85 and 52.05% in the number of grains infected with Fusarium spp. with respect to control for “San Juan” and “H-159”, respectively. For Fusarium monoliforme it was found that in 30 min there was a reduction of 53.74% for the hybrid “San Juan”, while for H-159 a reduction of 61.7% in 10 minutes was observed. These results show that UV-C radiation may be useful for application as a germicide in future experiments on a wide variety of grains.
Badano wykorzystanie promieniowania UV-C jako metody zwalczania naturalnych mikobiot ziarna hybryd kukurydzy (Zea mays L.) “San Juan” i ”H-159” (cykl produkcyjny, 2009). Zastosowano lampy UV-C o mocy 15 W, a czasy ekspozycji wynosiły 0, 5, 10, 15, 20, 25 oraz 30 min. Doświadczenie założono metodą kompletnych bloków randomizowanych w ośmiu i czterech powtórzeniach. Jednostka pilotażowa wynosiła 50 ziaren. Dla określenia mikobiot zastosowano test agarowy po uprzedniej dezynfekcji ziarna 3% roztworem podchlorynu sodu przez 1 min. Stwierdzono różnice (P ≤ 0,001, P ≤ 0,05) pomiędzy obiektami doświadczenia. Najlepsze wyniki uzyskano dla czasów ekspozycji 30 i 10 min, uzyskując odpowiednio 42,85 oraz 52,05% redukcję ilości ziaren zakażonych Fusarium spp. dla ziarna hybryd “San Juan” i “H-159” w odniesieniu do kontroli. W odniesieniu do Fusarium monoliforme stwierdzono, że po czasie naświetlania 30 min nastąpiła redukcja o 53,74% dla hybrydy “San Juan”, a dla H-159 stwierdzono spadek o 61,7% po 10 minutach. Te wyniki wykazują, że promieniowanie UV-C może być użyteczne do stosowania jako zabieg zarodnikobójczy w przyszłych doświadczeniach na rożnych rodzajach ziarna.
Źródło:
Acta Agrophysica; 2011, 18, 2[193]
1234-4125
Pojawia się w:
Acta Agrophysica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
***
Autorzy:
r., c.
Powiązania:
https://bibliotekanauki.pl/articles/943045.pdf
Data publikacji:
2005
Wydawca:
Związek Karaimów Polskich. Karaimska Oficyna Wydawnicza Bitik
Źródło:
Awazymyz. Pismo historyczno-społeczno-kulturalne Karaimów; 2005, 1 (10); 6-6
1733-7585
Pojawia się w:
Awazymyz. Pismo historyczno-społeczno-kulturalne Karaimów
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dependence in groups
Autorzy:
Lyndon, R.C.
Powiązania:
https://bibliotekanauki.pl/articles/725001.pdf
Data publikacji:
1966
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Źródło:
Colloquium Mathematicum; 1966, 14, 1; 275-283
0010-1354
Pojawia się w:
Colloquium Mathematicum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Equivalence of control systems on the Euclidean group SE (2)
Autorzy:
Adams, R. M.
Biggs, R.
Remsing, C. C.
Powiązania:
https://bibliotekanauki.pl/articles/205696.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
Left-invariant control system
state space equivalence
Euclidean group
Opis:
We classify, under (local) state space equivalence, all full-rank left-invariant control affne systems evolving on the Euclidean group SE(2).
Źródło:
Control and Cybernetics; 2012, 41, 3; 513-524
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Survey on Wireless Network Applications in Automated Public Utilities Control and Management
Autorzy:
Nayaka, R. J.
Biradar, R. C.
Powiązania:
https://bibliotekanauki.pl/articles/308729.pdf
Data publikacji:
2015
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
Automated Meter Reading
AMR
wireless sensor networks
WSN
Wireless communication
Short Message Services
SMS
Opis:
Public utilities such as water, electricity and gas are essential services that play a vital role in economic and social development. Automation of public utility services addresses the huge losses faced by the utility services today, due to non-accounting of distributed utility resources. Automation improves government revenues. The different type of architectures are proposed and designed for automated metering, control and management of public utilities like water, gas, and electricity for effective management and control of resources. The various network topologies, hardware and software architectures to automation and management of public utilities are proposed by researchers. In this paper, the different technologies proposed by various researchers across the globe are surveyed and list of issues and challenges for automated meter reading and control of public utilities is identified.
Źródło:
Journal of Telecommunications and Information Technology; 2015, 3; 13-24
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimation of diatom and dinoflagellate cell volumes from surface waters of the Northern Indian Ocean
Autorzy:
Chitari, R.R.
Anil, A.C.
Powiązania:
https://bibliotekanauki.pl/articles/47851.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
diatom
dinoflagellate
cell size
surface water
microphytoplankton
seasonal variation
spatial variation
Indian Ocean
Bengal Bay
Arabian Sea
Opis:
Phytoplankton samples collected from the Northern Indian Ocean (Bay of Bengal, northern Arabian Sea, and Dona Paula Bay Goa, west coast of India), were utilized to quantify changes in cell size, cell volume and carbon per cell of diatoms and dinoflagellates. The dataset from the Bay of Bengal also provides inter- and intra-annual variations (April 2008 to March 2010). The variations in cell size and volume were large in regions influenced by the riverine influx or terrigenous inputs. An interregional comparison of commonly available forms (8 species) points out that cell volumes are highest in the North Atlantic and lowest in the Mediterranean. The information provided will be useful in estimation of carbon biomass and biogeochemical studies.
Źródło:
Oceanologia; 2017, 59, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Probabilistic study of bone remodeling using finite element analysis
Autorzy:
Werner, C.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/265649.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
analiza probabilistyczna
przebudowa kości
analiza elementów skończonych
probabilistic analysis
bone remodeling
finite element analysis
Opis:
The dynamic bone remodeling process is a computationally challenging research area that struggles to understand the actual mechanisms. It has been observed that a mechanical stimulus in the bone greatly affects the remodeling process. A 3D finite element model of a femur is created and a probabilistic analysis is performed on the model. The probabilistic analysis measures the sensitivities of various parameters related to the material properties, geometric properties, and the three load cases defined as Single Leg Stance, Abduction, and Adduction. The sensitivity of each parameter is based on the calculated maximum mechanical stimulus and analyzed at various values of probabilities ranging from 0.001 to 0.999. The analysis showed that the parameters associated with the Single Leg Stance load case had the highest sensitivity with a probability of 0.99 and the angle of the force applied to the joint of the proximal femur had the overall highest sensitivity.
Źródło:
International Journal of Applied Mechanics and Engineering; 2013, 18, 3; 911-921
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parazytozy tropikalne na tle całokształtu problemów medycyny tropikalnej w Polsce
Tropical parasitoses on the background of problems of tropical medicine in Poland
Autorzy:
Dolmierski, R.
Zwierz, C.
Powiązania:
https://bibliotekanauki.pl/articles/836903.pdf
Data publikacji:
1988
Wydawca:
Polskie Towarzystwo Parazytologiczne
Tematy:
parazytologia lekarska
choroby inwazyjne
choroby pasozytnicze
choroby tropikalne
medycyna tropikalna
Polska
Źródło:
Annals of Parasitology; 1988, 34, 4-6
0043-5163
Pojawia się w:
Annals of Parasitology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lutowanie kompozytów miedź - grafen z ceramiką korundową za pomocą lutów aktywnych
Brazing of copper - graphene composites with alumina ceramic using active braze materials
Autorzy:
Strąk, C.
Siedlec, R.
Powiązania:
https://bibliotekanauki.pl/articles/192046.pdf
Data publikacji:
2014
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Materiałów Elektronicznych
Tematy:
lutowanie
kompozyt
zwilżalność
brazing
composite
wettability
Opis:
Do wykonania kompozytu objętościowego, przeznaczonego do lutowania, zastosowano proszki dostępnego handlowo grafenu oraz zredukowanego termicznie tlenku grafenu, na których osadzano tlenek miedzi metodą strącania z kąpieli elektrochemicznej. Proszki poddano obróbce termicznej w atmosferze beztlenowej, a następnie wyprasowano z nich kształtki na prasie służącej do prasowania i spiekania pod ciśnieniem. Uzyskane kompozyty spajano z ceramiką korundową za pomocą aktywnych lutów srebrowych (CB1). Przed procesem spajania kompozyty poddano procesowi galwanizacji miedzią. Zbadano mikrostrukturę i właściwości samego kompozytu oraz mikrostrukturę uzyskanych złączy. Na podstawie przeprowadzonych badań określono najkorzystniejsze warunki procesu spajania kompozytów.
To produce composites, commercial graphene powders and thermally reduced graphene oxide were used. Nanocrystalline copper oxide (CuO) thin films, synthesized by a sol–gel method, were deposited on the powders. These powders were annealed in an oxygen-free atmosphere and subsequently hot pressed. The outcome composites were bonded to alumina ceramic using active silver braze material (CB1). Before the process of bonding, the composites were plated with copper. The microstructure and properties of the composite and also the microstructure of the obtained joints were examined. Based on the studies carried out, optimal bonding conditions were determined.
Źródło:
Materiały Elektroniczne; 2014, T. 42, nr 4, 4; 4-15
0209-0058
Pojawia się w:
Materiały Elektroniczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Emergency management in the scope of research
Zarządzanie kryzysowe w świetle badań
Autorzy:
Koch, R.
Schafer, C.
Powiązania:
https://bibliotekanauki.pl/articles/373738.pdf
Data publikacji:
2012
Wydawca:
Centrum Naukowo-Badawcze Ochrony Przeciwpożarowej im. Józefa Tuliszkowskiego
Tematy:
badania w dziedzinie bezpieczeństwa publicznego
bezpieczeństwo i ochrona
orientacja na użytkownika końcowego
end user driven approach
research in public safety and security
Opis:
Research on IT.application in the domain of public safety and security is none of the traditional research areas in the field of emergency and disaster management. The availability of mobile and ruggedized computing equipment has been the enabler for these researches. C.I.K. focuses on user-integrated research in this context. Since 2007 specific funding schemes on European and national levels have been existing.
Badania aplikacji IT w dziedzinie bezpieczeństwa publicznego nie były do tej pory tradycyjnymi obszarami badawczymi w zakresie np. Zarządzania kryzysowego. Dostęność mobilnego I wstrząsoodpornego sprzętu komputerowego była bodźcem dla dla rozwoju tych badań. W tym kontekście CIK (Computer Application and Integration in Design and Planning) skupia się na badaniach dotyczących użytkownika końcowego. Od roku 2007 istnieją specjalne schematy finansowania zarówno na poziomie krajowym jak i międzynarodowym (UE).
Źródło:
Bezpieczeństwo i Technika Pożarnicza; 2012, 4; 19-22
1895-8443
Pojawia się w:
Bezpieczeństwo i Technika Pożarnicza
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A study on meme propagation in multimemetic algorithms
Autorzy:
Nogueras, R.
Cotta, C.
Powiązania:
https://bibliotekanauki.pl/articles/329698.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
memetic algorithm
spatial structure
meme propagation
algorytm memetyczny
struktura przestrzenna
Opis:
Multimemetic algorithms (MMAs) are a subclass of memetic algorithms in which memes are explicitly attached to genotypes and evolve alongside them. We analyze the propagation of memes in MMAs with a spatial structure. For this purpose we propose an idealized selecto-Lamarckian model that only features selection and local improvement, and study under which conditions good, high-potential memes can proliferate. We compare population models with panmictic and toroidal grid topologies. We show that the increased takeover time induced by the latter is essential for improving the chances for good memes to express themselves in the population by improving their hosts, hence enhancing their survival rates. Experiments realized with an actual MMA on three different complex pseudo-Boolean functions are consistent with these findings, indicating that memes are more successful in a spatially structured MMA, rather than in a panmictic MMA, and that the performance of the former is significantly better than that of its panmictic counterpart.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2015, 25, 3; 499-512
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new finite element technique for a phase field model of brittle fracture
Nowa metoda elementów skończonych dla modelu pól fazowych przy opisie kruchego pękania
Autorzy:
Kuhn, C.
Muller, R.
Powiązania:
https://bibliotekanauki.pl/articles/281852.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
phase field
fracture
finite elements
exponential shape functions
Opis:
Phase field models for fracture employ a continuous field variable to indicate cracks. The width of the transition zone between cracked and uncracked areas is controlled by a regularization parameter. The numerical implementation of such models is sensible to the choice of this parameter in conjunction with the mesh size, as the mesh has to be fine enough to resolve high gradients of the crack field appearing in the transition zones. This is the main computational limit and challenge of the implementation. To overcome this limitation, a finite element method using exponential shape functions is introduced. Numerical examples show that these new shape functions perform better than standar Lagrange shape functions.
Modele pól fazowych w opisie procesu pękania wykorzystują zmienne ciągłe pola do wykrywania pęknięć. Szerokość strefy przejściowej pomiędzy obszarem pęknięcia a nieuszkodzonym jest opisana parametrem regularyzacji. Numeryczna implementacja takich modeli jest wrażliwa na dobór tego parametru w połączeniu z rozmiarem siatki elementów skończonych, która musi być odpowiednio gęsta, by uwzględnić duże gradienty pola z pęknięciem w strefie przejściowej. Jest to główne ograniczenie w przeprowadzaniu obliczeń i duże wyzwanie symulacyjne. W pracy zaproponowano użycie wykładniczych funkcji kształtu do metody elementów skończonych w celu eliminacji tego ograniczenia. Przedstawione przykłady pokazały, że zastosowanie funkcji wykładniczych zamiast standardowych funkcji Lagrange’a wyraźnie poprawiło wydajność numeryczną modeli.
Źródło:
Journal of Theoretical and Applied Mechanics; 2011, 49, 4; 1115-1133
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Friction rolling with lateral slip in rail vehicles
Tarcie toczne z poślizgiem bocznym w pojazdach szynowych
Autorzy:
Konowrocki, R.
Bajer, C.
Powiązania:
https://bibliotekanauki.pl/articles/282025.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
rolling
friction
lateral slip
wheel-rail interaction
Opis:
The paper deals with the dynamic phenomena accompanying the wheel rolling over a road (rail, track), with lateral slip effects. They occur in rolling of a wheel and wheelset on a straight track in the case of lateral load and especially on curves. Different curvature radii and rotary oscillations of wheelsets result in skew rolling and, in turn, in lateral slip oscillation in the contact zone between the wheel and rail. It significantly increases noise and wear in real structures. Double periodicity of motion was detected in an underground train. Hitherto, this phenomenon has not been reported in the literature. Experimental investigation was performed on a test stand for various parameters: the angle of skew rolling, velocity and contact pressure. Results were related to a two degree-of-freedom theoretical system. In the case of steel/polyester and polyamide/polyester friction pair, qualitatively similar results were obtained.
W pracy omówiono zjawiska dynamiczne związane z toczniem się koła z poślizgiem bocznym po drodze (szynie, torze). Mają one miejsce przy toczeniu się kół lub zestawów kołowych po torze prostym, w przypadku bocznego obciążenia oraz na łukach. Różne promienie krzywizn oraz drgania skrętne zestawów kołowych powodują ukośne toczenie i boczne poślizgi w strefie kontaktu koła z szyną. Zjawisko to znacząco zwiększa hałas oraz zużycie elementów konstrukcji. W kolei podziemnej wykryto dwuokresowość drgań. Zjawisko to dotąd nie było opisywane w literaturze. Przeprowadzono stanowiskowe badania eksperymantalne z uwzględnieniem następujących parametrów: kąta ukośnego toczenia, prędkości oraz siły nacisku w strefie kontaktu. Wyniki odniesiono do ruchu teoretycznego układu o dwóch stopniach swobody. W przypadku par ciernych stal-poliester i poliamid-poliester uzyskano zbliżone jakościowo rezultaty.
Źródło:
Journal of Theoretical and Applied Mechanics; 2009, 47, 2; 275-293
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A concept of pusher - barge coupling device of two-segment ship for inland waterways and coastal service
Autorzy:
Dymarski, C.
Rolbiecki, R.
Powiązania:
https://bibliotekanauki.pl/articles/260471.pdf
Data publikacji:
2006
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
ship devices
hydraulic drive and control
Opis:
This paper presents design assumptions and a constructional concept of the device for coupling the pusher and hotel barge of two-segment inland waterways and coastal ship. The presented device makes it possible to reach either stiff connection or mutually controlled inclination of both segments against each other, which greatly improves the ship’s manoeuvrability and thus safety of navigation especially on narrow and meandering waterways.
Źródło:
Polish Maritime Research; 2006, S 2; 76-79
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Uproszczony model rozkładu pierśnic jednowiekowych niepielęgnowanych drzewostanów sosnowych (Pinus sylvestris L.)
Simplified model of diameter distribution for even-aged unthinned Scots pine (Pinus sylvestris L.) stands
Autorzy:
Jagiełło, R.
Beker, C.
Powiązania:
https://bibliotekanauki.pl/articles/986956.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
dendrometria
sosna zwyczajna
Pinus sylvestris
drzewostany sosnowe
drzewostany jednowiekowe
drzewostany niepielegnowane
rozklad piersnic
rozklad uproszczony
rozklad gamma
diameter distribution
gamma poisson
scots pine
unthinned stand
Opis:
Although modelling of the diameter at the breast height (DBH) distributions has long history, theoretical discrete distributions have not so far been used for this purpose. In this study we use measurements covering 25 years (six inventories) without silvicultural influence on 14 even−aged Scots pine (Pinus sylvestris L.) stands to develop the DBH distribution models. Analysed stands are located in Murowana Goślina Forest Experimental Station (W Poland). The objective of the study was to elaborate the most simplified model that applies stand variables easy to assess and uncomplicated theoretical distribution. We employed two−parameter Gamma Poisson (GP) distribution and compared it to Weibull (W) and Sb Johnson (SbJ) ones. When maximum likelihood estimation (MLE) was used, GP gave similar results to W and both were slightly worse than SbJ. We found that both DBH standard deviation and stand density have substantial impact for model bias when above distributions used. Stepwise regression analysis was used for obtaining linear equations for parameter prediction of GP distribution. Then, GP model was simplified by removing standard deviation of DBH (SDD) from equation for overdispersion parameter. Results showed slight increase in mean of error values (i.e. modified Reynolds e index and root mean square error) for simplified model (SGP) compared with those for model including SDD, but differences in means were insignificant. Minimal and mean DBH represent enough variability of diameter distribution to obtain appropriate model based on Gamma Poisson distribution. Error was only 5% greater from four−parameter SbJ (MLE) distribution with similar range: 8.2−28.8% against 5.1−25.5% for SGP and SbJ respectively. The presented model can be used in many branches of forestry for more accurate calculation of stand level variables, when additional allometric equations employed, for instance assimilation apparatus volume or below− and aboveground biomass.
Źródło:
Sylwan; 2017, 161, 10; 822-830
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimal regularity and optimal control of a thermoelastic structural acoustic model with point control and clamped boundary conditions
Autorzy:
Lebiedzik, C.
Triggiani, R.
Powiązania:
https://bibliotekanauki.pl/articles/970762.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
point control
parabolic/hyperbolic thermoelastic system
hyperbolic/hyperbolic chamber/wall coupling
Opis:
In this paper we consider point control of a structural acoustic model with thermoelastic effects. The key feature of this paper is that the two-dimensional plate modeling the active wall of the acoustic chamber has clamped boundary conditions. For this case a new optimal regularity result has recently become available (Triggiani, 2008). Using this new result for the plate alone, we derive a sharp (optimal) regularity result for the overall coupled system of wave and thermoelastic plate equations, after overcoming a series of additional technical difficulties. This allows for the study of an optimal control problem of the coupled system.
Źródło:
Control and Cybernetics; 2009, 38, 4B; 1461-1499
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Climate change research - what do we need really?
Autorzy:
Prasad, P.R.C.
Powiązania:
https://bibliotekanauki.pl/articles/12022.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
This research note focuses on the current climate change research scenario and discusses primarily what is required in the present global climate change conditions. Most of the climate change research and models predict adverse future conditions that have to be faced by humanity, with less emphasis on mitigation measures. Moreover, research ends as reports on the shelves of scientists and researchers and as publications in journals. At this juncture the major focus should be on research that helps in reducing the impact rather than on analysing future scenarios of climate change using different models. The article raises several questions and suggestions regards climate change research and lays emphasis on what we really need from climate change researchers.
Źródło:
Papers on Global Change; 2015, 22
2300-8121
1730-802X
Pojawia się w:
Papers on Global Change
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badanie poziomu zadowolenia pracowników z elastycznych form organizacji czasu pracy
The survey of employee satisfaction of flexible forms of organization of working time
Autorzy:
Bartnicka, C.
Czyż, R.
Powiązania:
https://bibliotekanauki.pl/articles/113155.pdf
Data publikacji:
2017
Wydawca:
STE GROUP
Tematy:
czas pracy
zadowolenie pracownika
satysfakcja pracownika
system pracy
working time
employee contentment
employee satisfaction
work system
Opis:
Przedsiębiorcy coraz częściej dają pracownikom możliwość korzystania z elastycznych form organizacji czasu pracy. Staje się to przywilejem dla pracowników. Taki system zapewnia zatrudnionym work-life balance, daje komfort psychiczny, zadowolenie i wpływa na ich chęć kontynuacji kariery zawodowej w firmie, co stanowi zarówno korzyść dla pracownika, jak i pracodawcy. Praca zawiera przegląd najczęściej stosowanych w praktyce form organizacji czasu pracy. W artykule przedstawiono wyniki i wnioski z badania przeprowadzonego w formie ankietowej, którego celem było sprawdzenie poziomu zadowolenia pracowników z elastycznych form organizacji czasu pracy.
The Employers increasingly give employees the possibility of using flexible forms of organization of working time. It becomes a privilege for employees. System like that provides for employees work-life balance, gives psychological comfort, satisfaction and affects on their willingness to continue careers in the company, which is a benefit for both: the employee and the employer. The work provides an overview of the most commonly used forms of organization of working time. The article presents the results and conclusions of a survey, which the purpose was to check employee satisfaction of flexible forms of organization of working time.
Źródło:
Systemy Wspomagania w Inżynierii Produkcji; 2017, 6, 6; 11-22
2391-9361
Pojawia się w:
Systemy Wspomagania w Inżynierii Produkcji
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Occupational Exposure to Power Frequency Fields in Some Electrical Transformation Stations in Romania
Autorzy:
Goiceanu, C.
Danulescu, R.
Powiązania:
https://bibliotekanauki.pl/articles/90127.pdf
Data publikacji:
2006
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
narażenie zawodowe
power frequency
electric and magnetic fields
occupational exposure
transformation stations
transformator
pole elektromagnetyczne
zagrożenia zdrowia
Rumunia
Opis:
The aim of this study is to investigate the levels of electric and magnetic power frequency fields at 8 electrical transformation stations in the North-East counties of Romania and to check their compliance with standards Spot measurements were carried out on both electric and magnetic fields under overhead conductors of 110-, 220- and 380-kV installations. The magnetic field levels were several orders of magnitude below the reference level for occupational exposure set by ICNIRP (International Commission on Non-Ionizing Radiation) or by Romanian regulations. In contrast, the electric field levels were about the same order of magnitude as the reference levels. In 2 electrical stations the reference level of 10 kV/m was exceeded at specific locations within the outdoor installations area. However, the additional reference level for short-time exposure included in Romanian regulations, 30 kV/m, was not exceeded.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2006, 12, 2; 149-153
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The growth performance of selected spice crops in Haryana state
Procesy wzrostu wybranych upraw roślin przyprawowych w rejonie Harijana
Autorzy:
Lal, C.
Kait, R.
Powiązania:
https://bibliotekanauki.pl/articles/2048607.pdf
Data publikacji:
2021
Wydawca:
Akademia Bialska Nauk Stosowanych im. Jana Pawła II w Białej Podlaskiej
Tematy:
indebtedness
farmers
loan
farm-size
Opis:
Subject and purpose of work: The study aims to assess the nature, extent and sources of debt and the measures of the burden of debt on farmers. Materials and methods: The study was based on primary data collected (by field survey) from a sample of 600 farmers selected from Haryana state in India. With regards to the selection of farmers/respondents, a proportionate sampling technique was employed. For the analysis of the collected data, average (or mean value) and percentage techniques were used. The data were collected in January, February and March, 2021. Results: The study revealed that the average amount of debt per sampled farmer is 563 960 rupees. This amount of debt is very high. Institutional sources played a major role in loan disbursement to farmers. Of the total amount owed, one third of all the debt was incurred from non-institutional sources at a higher rate of interest; 67.03% was incurred for productive purposes and the remaining 32.97% of debt was incurred for non-productive purposes. Non-productive debt adds nothing to agricultural production. 67% of all farmers in the state belong to marginal and small farm-size category. Thus, at small size of land holdings, at higher rate of interest charged by non-institutional sources and non-productive loans are the main cause of farmer indebtedness. Conclusions: Farmers have been trapped under the burden of debt and are not in a situation to pay their loans back within the prescribed period of time.
Źródło:
Economic and Regional Studies; 2021, 14, 3; 373-384
2083-3725
2451-182X
Pojawia się w:
Economic and Regional Studies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Charakterystyka procesów erozyjnych gleb na przykładzie zlewni wybranych rzek w Karpatach
Soil erosion processes in the Carpathian mountain regions
Autorzy:
Lipski, C.
Kostuch, R.
Powiązania:
https://bibliotekanauki.pl/articles/60482.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Infrastruktura i Ekologia Terenów Wiejskich PAN
Tematy:
tereny gorskie
Karpaty
zlewnie rzek
zlewnie gorskie
zlewnia Soly
zlewnia Skawy
zlewnia Raby
gleby
procesy erozyjne
zmyw erozyjny
spadek terenu
osuwiska
erozja zlobinowa
erozja powierzchniowa
Opis:
Autorzy opisują jakie procesy erozyjne gleb występują w górskich terenach Karpat i czym są powodowane. Głównymi przyczynami występowania intensywniejszych procesów erozji na omawianym obszarze są przede wszystkim większe, częstsze i bardziej intensywne opady atmosferyczne oraz większe pochylenia powierzchni terenu. Najsilniej erodowane są przede wszystkim gleby orne, ponieważ w pewnych okresach nie są pokryte roślinnością. Oprócz erozji wodnej występuje tu również erozja wietrzna. Wody opadowe powodują zarówno erozję powierzchniową, liniową, jak też osuwiskową. Każda z wymienionych form erozji została przez autorów omówiona w artykule.
The authors show in the paper which types of soil erosion occur in the Carpathian mountain region and what are causes of it. It was found that the most susceptible to soil erosion were arable lands because of their surface being periodically devoid of plant cover. On the arable lands two types of soil erosion: surface and wind erosion can be found. Sometimes one can also find rill erosion and land slides. On the mountain grasslands, the most frequent are landslides which occur also in the forests on slopes with inclination. The main cause of soil erosion is the waterproof clay part on which a surface layer of soil slides down. All described types of soil erosion are very dangerous for environment because degrade the soils, pollute the surface waters, lower the agricultural and grassland production and lower the landscape values. The occurrence of soil erosion in mountain regions is caused first of all by larger and more intensive rainfalls and inclination of the slopes.
Źródło:
Infrastruktura i Ekologia Terenów Wiejskich; 2005, 3
1732-5587
Pojawia się w:
Infrastruktura i Ekologia Terenów Wiejskich
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Czynnik społeczny w kontekście prowadzenia wielofunkcyjnej i zrównoważonej gospodarki leśnej
Social factor in the context of conducting multifunctional and sustainable forest management
Autorzy:
Beker, C.
Jaszczak, R.
Powiązania:
https://bibliotekanauki.pl/articles/791523.pdf
Data publikacji:
2017
Wydawca:
Wyższa Szkoła Zarządzania Środowiskiem w Tucholi
Tematy:
lasy
lasy miejskie
lasy panstwowe
funkcje lasu
gospodarka lesna
gospodarka zrownowazona
czynniki spoleczne
forest
urban forest
national forest
forest economy
sustainable economy
social factor
Źródło:
Zarządzanie Ochroną Przyrody w Lasach; 2017, 11
2081-1438
2391-4106
Pojawia się w:
Zarządzanie Ochroną Przyrody w Lasach
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A novel flattened gain C-band cascaded hybrid optical Raman and thulium-doped fluoride fiber amplifier for super dense wavelength division multiplexing system
Autorzy:
Kumar, C.
Goyal, R.
Powiązania:
https://bibliotekanauki.pl/articles/174394.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
gain
noise figure
Raman amplifier
thulium-doped fluoride fiber
TDFF amplifier
super dense wavelength division multiplexing
SD-WDM
hybrid optical amplifier
Opis:
In this paper, we have reported a very advanced hybrid optical amplifier (Raman-TDFF amplifier) for the 180 × 10 Gbps super dense wavelength division multiplexing system with the channel spacing of 100 GHz. The performances of the model have been evaluated in terms of gain and noise figures for the C-band (from 1525 to 1565 nm). Gain flatness (> 21 dB) is recorded with the least variation of 2.5 dB without using any cost effective technique. Further, the effect of the proposed hybrid optical amplifier has also been analyzed with slightly shifting the wavelength spectrum for the same feature.
Źródło:
Optica Applicata; 2018, 48, 2; 173-177
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bezpośredni i następczy wpływ kompostów sporządzonych na bazie komunalnego osadu ściekowego na fotosyntezę rzepaku jarego i pszenicy ozimej
Autorzy:
Maciorowski, R.
Woloszyk, C.
Powiązania:
https://bibliotekanauki.pl/articles/798403.pdf
Data publikacji:
2003
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Opis:
W pracy oceniano wpływ nawożenia kompostami sporządzonymi na bazie komunalnego osadu ściekowego z różnymi dodatkami (odpady z zieleni miejskiej, słoma, popiół z węgla kamiennego), na tle nawożenia mineralnego, na parametry fotosyntezy rzepaku i pszenicy ozimej. Podjęto również próbę określenia przydatności badanych parametrów fotosyntezy do monitorowania zmian w troficznym oddziaływaniu nawożenia organiczno-mineralnego. Komposty z osadu ściekowego z dodatkiem różnych komponentów w podobny sposób wpływały na proces fotosyntezy roślin rzepaku jarego i pszenicy ozimej oceniany techniką indukowanej fluorescencji chlorofilu, natężeniem wymiany gazowej oraz zawartością chlorofilu. W porównaniu z wariantem kontrolnym stwierdzono wyłącznie pozytywny efekt działania kompostów na proces fotosyntezy. Zawartość chlorofilu mierzona techniką fotooptyczną była najlepiej skorelowana z plonem nasion i w związku z tym może być przydatnym parametrem do oceny nawozowego działania kompostów.
In the paper, the influence of composts produced from municipal sewage sludge with different components (municipal green wastes, straw, pit coal ash) in combination with mineral fertilization, on photosynthesis of rape and wheat was examined. The effect of different composts on photosynthesis estimated by fluorescence technique, gas exchange and chlorophyll content of rape and wheat was similar. Only positive effect of composts was found out. The chlorophyll content measured by means of photo optical techniques was the best correlated with the seed yield from that reason it may be useful parameter for evaluating the fertilizer effect of composts.
Źródło:
Zeszyty Problemowe Postępów Nauk Rolniczych; 2003, 494
0084-5477
Pojawia się w:
Zeszyty Problemowe Postępów Nauk Rolniczych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Metody oceny stanu technicznego układu Common Rail z wykorzystaniem systemów komputerowych
Diagnostic processes of Common Rail unit based on computer systems
Autorzy:
Bocheński, C.
Mruk, R.
Powiązania:
https://bibliotekanauki.pl/articles/328151.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
diagnostyka
silnik
common rail
system wtrysku
sieć neuronowa
diagnostics
self-ignition engine
injection system
neural networks
Opis:
W artykule przedstawiono problematykę procesów diagnostyki technicznej w czasie pracy silnika z zapłonem samoczynnym. Przedstawiono rozwiązanie stanowiska badawczego wraz z oprogramowaniem sterującym pozwalającym na przeprowadzenie badań procesów diagnostycznych oraz przedstawiono wyniki badań opracowanych algorytmów diagnostycznych dla układu wtryskowego typu Common Rail.
The paper presented problems of diagnostic processes within function of self-ignition engine. There is presented a measuring stand of together with a controlling software enabling to research the diagnostic processes and result of investigation elaborate diagnostic algorithms of Common Rail injection system.
Źródło:
Diagnostyka; 2002, 27; 11-16
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simplified dynamic model of rotating beam
Uproszczony model dynamiczny wirującej belki
Autorzy:
Hein, R.
Orlikowski, C.
Powiązania:
https://bibliotekanauki.pl/articles/329004.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
mechanical system
modelling
vibration
modal analysis
model reduction
układy mechaniczne
modelowanie
drgania
analiza modalna
redukcja modeli
Opis:
In the paper a hybrid model of rotating beam is presented. It was obtained by using two methods: modal decomposition and spatial discretization. Reduced modal model was built for the system without the load related to inertia forces that occur during beam rotation. This inertia load was next modeled by using the method of simply spatial discretization and combined with reduced modal model. This approach allows to obtain accurate low-order model of rotating beam.
W artykule przedstawiono hybrydowy model wirującej belki. Otrzymano go stosując dwie metody: dekompozycji modalnej oraz dyskretyzacji przestrzennej. Zredukowany model modalny zbudowano dla układu bez obciążenia wynikającego z działania sił bezwładności występujących podczas ruchu belki. Oddziaływanie to uwzględniono stosując metodę dyskretyzacji przestrzennej. Takie podejście umożliwia otrzymanie dokładnego modelu niskiego rzędu wirującej belki.
Źródło:
Diagnostyka; 2013, 14, 2; 43-48
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Operational characteristic of selected marine turbounits powered by steam from auxiliary oil-fired boilers
Autorzy:
Behrendt, C.
Stoyanov, R.
Powiązania:
https://bibliotekanauki.pl/articles/27315949.pdf
Data publikacji:
2018
Wydawca:
STE GROUP
Tematy:
pomocnicze morskie turbiny parowe
cecha eksploatacyjna
turbina parowa
marine auxiliary steam turbounits
exploitation characteristics
steam turbines
Opis:
This paper presents characteristic values and operational parameters of two selected marine auxiliary steam turbine units such as efficiency, and steam consumption per unit or per hour. For the purpose of the analysis, the cargo turbine pumps and turbogenerator have been selected. The characteristic values and operational parameters have been determined using the operational tests results for the turbounits installed on oil tankers at various power loads.
Źródło:
New Trends in Production Engineering; 2018, 1, 1; 495-501
2545-2843
Pojawia się w:
New Trends in Production Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of magnetic field on thermal instability of Oldroydian viscoelastic rotating fluid in porous medium
Autorzy:
Thakur, R. C.
Rana, G. C.
Powiązania:
https://bibliotekanauki.pl/articles/265340.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
pole magnatyczne
materiały porowate
rotacja
niestabilność termiczna
magnetic field
Oldroydian viscoelastic fluid
porous medium
rotation
thermal instability
Opis:
In this paper, we investigate the effect of a vertical magnetic field on thermal instability of an Oldroydian visco-elastic rotating fluid in a porous medium. By applying the normal mode analysis method, the dispersion relation governing the effects of rotation, magnetic field and medium permeability is derived and solved analytically and numerically. For the case of stationary convection, the Oldroydian viscoelastic fluid behaves like an ordinary Newtonian fluid and it is observed that rotation has a stabilizing effect while the magnetic field and medium permeability have a stabilizing/destabilizing effect under certain conditions on thermal instability of the Oldroydian viscoelastic fluid in a porous medium. The oscillatory modes are introduced due to the presence of rotation, the magnetic field and gravity field. It is also observed that the ‘principle of exchange of stability’ is invalid in the presence of rotation and the magnetic field.
Źródło:
International Journal of Applied Mechanics and Engineering; 2013, 18, 2; 555-569
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Correlates of snail shell variation along a unidirectional freshwater gradient in Lithasia geniculata (Haldeman, 1840) (Caenogastropoda: Pleuroceridae) from the Duck River, Tennessee, USA
Autorzy:
Minton, R.
Hart, K.C.
Fiorillo, R.
Brown, C.
Powiązania:
https://bibliotekanauki.pl/articles/84595.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Mikołaja Kopernika. Wydział Biologii i Ochrony Środowiska. Stowarzyszenie Malakologów Polskich
Źródło:
Folia Malacologica; 2018, 26, 2
1506-7629
Pojawia się w:
Folia Malacologica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Integrating coagulation and Fenton’s oxidation for pharmaceutical effluents treatment
Koagulacja połączona z utlenianiem Fentona w oczyszczaniu ścieków farmaceutycznych
Autorzy:
Martins, R. C.
Oliveira, A. C.
Quinta-Ferreira, R. M.
Powiązania:
https://bibliotekanauki.pl/articles/2073214.pdf
Data publikacji:
2015
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
pharmaceutical wastewater
heterogeneous Fenton's process
photo-Fenton process
low cost catalysts
biodegradability
ścieki farmaceutyczne
heterogeniczny proces Fentona
reakcja foto-Fentona
kataliza nisko-kosztowa
biodegradowalność
Opis:
Pharmaceutical industry produces complex and bio-refractory wastewater whose discharge throughout water courses constitutes an environmental danger. Although several works can be found handling with simulated pharmaceutical effluents, data reporting results gathered using actual wastewater is still scarce. This work reveals that Fe-Ce-O and red volcanic rock are interesting catalysts for dark and photo-Fenton. Furthermore, the light/H2O2 system showed interesting results and it is now being explored at the pilot scale by the pharmaceutical industry that provided the effluent.
Przemysł farmaceutyczny wytwarza złożone i bioodporne ścieki, których zrzut zwykła drogą stwarza zagrożenie dla środowiska. Pomimo tego, że kilka prac zajmuje się transportem symulowanych ciekłych odpadów farmaceutycznych, dane dotyczące rzeczywistych ścieków są wciąż skąpe. W prezentowanej pracy stwierdzono, że Fe-Ce-O i czerwona skała wulkaniczna są ciekawymi katalizatorami w reakcji foto-Fentona. Ponadto układ światło/H2O2 wykazał się interesującymi właściwościami i obecnie jest badany w skali pilotowej przy obróbce ścieków w przemyśle farmaceutycznym.
Źródło:
Inżynieria i Aparatura Chemiczna; 2015, 4; 174--177
0368-0827
Pojawia się w:
Inżynieria i Aparatura Chemiczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of precise point positioning algorithm to support advanced driver assistant functions for inland vessel navigation
Autorzy:
Lass, C.
Ziebold, R.
Powiązania:
https://bibliotekanauki.pl/articles/2063986.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
real tme kinematic
Global Navigation Satellite Systems
state space representation
VHF Data Exchange System
precise point positioning
navigation and timing
Automatic Identification System
inland navigation
Opis:
Bridge passing and passing waterway locks are two of the most challenging phases for inland vessel navigation. In order to be able to automate these critical phases very precise and reliable position, navigation and timing (PNT) information are required. Here, the application of code-based positioning using signals of Global Navigation Satellite Systems (GNSS) is not sufficient anymore and phase-based positioning needs to be applied. Due to the larger coverage area and the reduction of the amount of correction data Precise Point Positioning (PPP) has significant advantages compared to the established Real Time Kinematic (RTK) positioning. PPP is seen as the key enabler for highly automatic driving for both road and inland waterway transport. This paper gives an overview of the current status of the developments of the PPP algorithm, which should finally be applied in advanced driver assistant functions. For the final application State Space Representation (SSR) correction data from SAPOS (Satellitenpositionierungsdienst der deutschen Landesvermessung) will be used, which will be transmitted over VDES (VHF Data Exchange System), the next generation AIS.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2021, 15, 3; 781--789
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł

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