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Wyświetlanie 1-59 z 59
Tytuł:
Spanish Sign Language Interpreter for Mexican Linguistics
Autorzy:
Pérez, A.
Powiązania:
https://bibliotekanauki.pl/articles/108686.pdf
Data publikacji:
2012
Wydawca:
Społeczna Akademia Nauk w Łodzi
Tematy:
Mexican Sign Language (MLS)
spoken language translation
sign animation
sintactic algorithm
Opis:
We present here the first visual interface for a Mexican Spanish Sign Language translator on its first development stage: sign-writing recognition. The software was developed for the unique characteristics of Mexican linguistics and was designed in order to use sentences or a sequence of signs in sign-writing system which are decoded by the program and converted into a series of images with movement that correspond to the Mexican sign language system. Using a lexical, syntactic and semantic algorithms plus free software such as APIss from Java, video converter software, data base manager like MySQL, Postgres and SQlite, was possible to read and interpret the rich and complex Mexican language. Our application for visual interface showed to be capable of reading and reconstruct each sentence used for the interpreter and translate it into a high definition video. The average time of video display vs number of sentences to interpret, probed to be in linear relation with an average time of two seconds per sentence. The software has overcome the problem of homonym words frequently used in Spanish language and verb tense relation for each sentence, special symbols such as #, %, $, etc. are still not recognized into the software.
Źródło:
Journal of Applied Computer Science Methods; 2012, 4 No. 1; 75-85
1689-9636
Pojawia się w:
Journal of Applied Computer Science Methods
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reinterpretation of the Spanish Late Jurassic “Hispaniachelys prebetica” as an indeterminate plesiochelyid turtle
Autorzy:
Perez-Garcia, A.
Powiązania:
https://bibliotekanauki.pl/articles/20182.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
A partial postcranial skeleton (carapace, plastron, and other poorly preserved elements) of a turtle, from the late Oxfordian of the Betic Range of Spain, has recently been assigned to a new taxon, Hispaniachelys prebetica. This is one of the few European turtle taxa reported from pre-Kimmeridgian levels, and the oldest turtle so far known from southern Europe. The character combination identified in that taxon (including the presence of cleithra, and single cervical scale) did not allow its assignment to Plesiochelyidae, a group of turtles very abundant and diverse in the Late Jurassic of Europe. The revision of the single specimen assigned to this taxon led to the reinterpretation of some of its elements, being reassigned to Plesiochelyidae. This study confirms the presence of Plesiochelyidae in the Oxfordian. However, because the Spanish taxon does not present a unique combination of characters, it is proposed as a nomen dubium.
Źródło:
Acta Palaeontologica Polonica; 2014, 59, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis and Classification of the Tools for Assessing the Risks Associated With Industrial Machines
Autorzy:
Paques, J. J.
Gauthier, F.
Perez, A.
Powiązania:
https://bibliotekanauki.pl/articles/90856.pdf
Data publikacji:
2007
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
risk
assessment
estimation
methods
tools
safety
machinery
Opis:
To assess and plan future risk-analysis research projects, 275 documents describing methods and tools for assessing the risks associated with industrial machines or with other sectors such as the military, and the nuclear and aeronautics industries, etc., were collected. These documents were in the format of published books or papers, standards, technical guides and company procedures collected throughout industry. From the collected documents, 112 documents were selected for analysis; 108 methods applied or potentially applicable for assessing the risks associated with industrial machines were analyzed and classified. This paper presents the main quantitative results of the analysis of the methods and tools.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2007, 13, 2; 173-187
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The European Early Cretaceous cryptodiran turtle Chitracephalus dumonii and the diversity of a poorly known lineage of turtles
Autorzy:
Perez-Garcia, A.
Powiązania:
https://bibliotekanauki.pl/articles/21609.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Europe
Lower Cretaceous
cryptodiran turtle
turtle
Chitracephalus dumonii
animal diversity
Testudines
Eucryptodira
Cryptodira
Cretaceous
Belgium
Spain
synonym
paleontology
phylogenetic analysis
systematics
holotype
Salasemys pulcherrima
Opis:
Chitracephalus dumonii was named based on some of the most complete turtle remains from the Lower Cretaceous of Europe, and yet the taxon has barely been mentioned since. Indeed, new specimens were erroneously attributed to a new taxon, “Salasemys pulcherrima”. The synonymy is recognized here, and this extends the geographical range of this turtle and provides examples of individuals at different stages of ontogenetic development. The peculiar structure of its shell, and its ontogenetic development, are unique to this taxon. The systematic position of C. dumonii was previously unclear, usually being referred to Testudinata incertae sedis. Here, it is placed in a cladistic analysis, which shows that C. dumonii, and the recently described Hoyasemys jimenezi form part of a Lower Cretaceous European clade of Cryptodira that includes “macrobaenid”, “sinemydid”, and panchelonioidean turtles.
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Functional morphology and modifications on spine growth in the productid brachiopod Heteralosia slocomi
Autorzy:
Perez-Huerta, A.
Powiązania:
https://bibliotekanauki.pl/articles/22228.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
functional morphology
modification
spine growth
productid brachiopod
brachiopod
Heteralosia slocomi
Brachiopoda
Productida
tubular hollow spine
silicification
ontogenesis
paleoecology
Opis:
Spines are one of the most characteristic ornamenting features of many fossil brachiopod taxa. Despite several studies of spines in different species, there is still insufficient information about the development, functionalmorphology, andmodifications of brachiopod spines. In particular, ontogenetic data are very rare and the understanding of the relationship between functional morphology and paleoecology is elusive. The present study analyzes the functional morphology and modifications on spines of the Pennsylvanian brachiopod species Heteralosia slocomi throughout ontogeny. Spines are tubular hollow and only displayed on the surface of the ventral valves, where they develop from a specific point at the margins of the growth lamellae and directed towards the anterolateral margins.Modifications of up to 180 from this original direction of growth are observed in response to ecological pressure and biotic interactions. The function of these spines is primarily for attachment by clasping and cementation, but the possibility of spines acting as sensory mechanisms is not excluded.
Źródło:
Acta Palaeontologica Polonica; 2013, 58, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A tale of two lead ingots
Opowieść o dwóch sztabach ołowiu
Autorzy:
Vernon, R. W.
Pérez, A. A.
Lorenc, M. W.
Powiązania:
https://bibliotekanauki.pl/articles/122193.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
Linares
Sopwith
lead ingots
Odyssey Marine Exploration
English Channel
sztaby ołowiu
Kanał la Manche
Opis:
Lead ores, usually containing silver, can be found in most European countries. It was the Romans who first mined lead extensively. They found many uses for it and developed techniques to extract the silver. However, the water table frequently determined the depth of Roman mining operations. In the 19th century, Spain became an important source of lead. Many of the mines had hardly been worked since the Romans and the relatively un-worked lead veins at Linares (Jaén Province), soon attracted companies, from Britain, France and Germany, and they introduced new technology into the area that allowed the mine working to go deeper. One of these mines La Tortilla mine, located to the west of the town, and managed by an Englishman, Thomas Sopwith junior was one of the many successful mines in the area. By 1880 an extensive lead smelting works had been established adjacent to the mine that produced large tonnages of lead ingots for export. Until recently, no lead ingots from the Linares area were known to have survived. However, it was inevitably some ingots would get lost in transit. The exploration of a shipwreck in 2005 revealed a large consignment of ingots manufactured at the La Tortilla smelter. This was as important discovery as the cargo represented the only known collection of ingots manufactured in Linares. This is the tale of two of those lead ingots.
Rudy ołowiu, zwykle zawierające srebro, można znaleźć w większości krajów europejskich. To Rzymianie najpierw ekstensywnie wydobywali ołów. Znaleźli wiele zastosowań i opracowali techniki ekstrakcji srebra. Jednak stół wodny często określał głębokość rzymskich operacji górniczych. W XIX wieku Hiszpania stała się ważnym źródłem ołowiu. Wiele kopalń nie pracowało od czasów rzymskich i stosunkowo nieobrobione żyły w Linares (prowincja Jaén), wkrótce przyciągnęły firmy z Wielkiej Brytanii, Francji i Niemiec, a także wprowadziły nowe technologie do obszaru, który pozwolił na działanie kopalni iść głębiej. Jedna z kopalni La Tortilla, zlokalizowana na zachód od miasta i zarządzana przez Anglika, Thomas Sopwith junior była jedną z wielu udanych kopalni w okolicy. Do 1880 r. w pobliżu kopalni powstały rozległe huty ołowiu, które produkowały duże ilości wlewków na eksport. Do niedawna wiadomo, że nie zachowały się wlewki ołowiu z obszaru Linares. Jednak nieuchronnie część wlewków zagubiłaby się w transporcie. Eksploracja wraku w 2005 r. ujawniła dużą partię wlewków wyprodukowanych w hucie La Tortilla. Było to równie ważne odkrycie jak ładunek stanowił jedyną znaną kolekcję wlewków wyprodukowanych w Linares. Jest to opowieść o dwóch z tych wlewków.
Źródło:
Hereditas Minariorum; 2017, 4; 9-24
2391-9450
2450-4114
Pojawia się w:
Hereditas Minariorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flotacja jonowa cynku z rozcieńczonych kwaśnych roztworów wodnych
Zinc ion flotation from diluted aqueous acid solutions
Autorzy:
Kawalec-Pietrenko, B.
Konopacka-Łyskawa, D.
Rybarczyk, P.
Perez, J.
Perez, A.
Powiązania:
https://bibliotekanauki.pl/articles/2070837.pdf
Data publikacji:
2009
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
flotacja jonowa
cynk
prędkość powietrza
stężenie substancji powierzchniowo-czynnej
ion floation
zinc
air flow rate
surfactant concentration
Opis:
Usuwano jony cynku z modelowych roztworów o pH = 5 w procesie separacji pianowej. Wyznaczono zmiany stopnia wyflotowania i współczynnika wzbogacenia w zależności od prędkości przepływu powietrza oraz stężenia siarczanu dodecylosodowego jako surfaktantu anionowego.
Zinc ions were removed from model solutions of pH = 5 by foam separation process. Values of removal ratio and the enrichment coefficient were determined in a form of dependence of gas velocity and n-dodecyl sodium sulfate concentration as anionie surfactant.
Źródło:
Inżynieria i Aparatura Chemiczna; 2009, 6; 102-103
0368-0827
Pojawia się w:
Inżynieria i Aparatura Chemiczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hexagonal Photonic Crystal Fiber Behaviour as a Chromatic Dispersion Compensator of a 40 Gbps Link
Autorzy:
Betancur-Pérez, A. F.
Botero-Cadavid, J. F.
Reyes-Vera, E.
Gómez-Cardona, N.
Powiązania:
https://bibliotekanauki.pl/articles/226794.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
BER
chromatic dispersion
DWDM
photonic crystal fibers
vector finite element method
Opis:
In this paper, the capabilities of chromatic dispersion compensation of a photonic crystal fiber with a hexagonal distribution of circular air holes was investigated. The vector finite element method with scattering boundary condition was used to analyze a set of configurations of the fiber in which the distance between air holes’ centers was modified. With this method it was possible to obtain the values of chromatic dispersion and confinement factor in the C fiber band. The best suited configurations were tested in a 160 km optical link with a bit rate of 40 Gbps. The performance was evaluated by measuring the bit error rate for a set of 20 channels with channel spacing of 100 GHz. T e simulation results showed that is possible to reach values of hromatic dispersion as low as −850 ps/nm⋅km, confinement losses close to 10⁻³ dB/km and good BER results in the order of 10⁻¹⁷ for a wavelength of 1550 nm.
Źródło:
International Journal of Electronics and Telecommunications; 2017, 63, 1; 93-98
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On operator ideals related to (p,σ)-absolutely continuous operators
Autorzy:
López Molina, J. A.
Sánchez Pérez, E. A.
Powiązania:
https://bibliotekanauki.pl/articles/1206151.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
tensor norms
operator ideals
(p,σ)-absolutely continuous operators
$g_{p,σ}$-nuclear and $g_{p,σ}$ integral operators
Opis:
We study tensor norms and operator ideals related to the ideal $P_{p,σ}$, 1 < p < ∞, 0 < σ < 1, of (p,σ)-absolutely continuous operators of Matter. If α is the tensor norm associated with $P_{p,σ}$ (in the sense of Defant and Floret), we characterize the $(α')^t$-nuclear and $(α')^t$- integral operators by factorizations by means of the composition of the inclusion map $L^r(μ) → L^1(μ) + L^p(μ)$ with a diagonal operator $B_w:L^{∞}(μ) → L^r(μ)$, where r is the conjugate exponent of p'/(1-σ). As an application we study the reflexivity of the components of the ideal $P_{p,σ}$.
Źródło:
Studia Mathematica; 2000, 138, 1; 25-40
0039-3223
Pojawia się w:
Studia Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new turtle species of Brodiechelys from the Early Cretaceous of Spain: Systematic and palaeobiogeographic implications
Autorzy:
Perez-Garcia, A.
Gasaulla, J.M.
Ortega, F.
Powiązania:
https://bibliotekanauki.pl/articles/946018.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
testudines
pan-cryptodira
xinjiangchelyidae
brodiechelys
cretaceous
europe
spain
Opis:
Brodiechelys brodiei is an Early Cretaceous turtle from Great Britain, the only species of the genus. This taxon has been shown in recent phylogenies to be closely related to Xinjiangchelyidae and therefore could be the only representative of this group in Europe. Here, we present several specimens from the Early Cretaceous Maestrazgo Basin, in the Iberian Range of Spain attributed to the British genus, and to a new species, Brodiechelys royoi. This discovery shows that, as previously observed with terrestrial turtles, some freshwater turtle taxa had a wide European distribution during the Early Cretaceous, being present in both Britain and the Iberian Peninsula. This study sheds new light on the phylogenetic position of this enigmatic genus, supporting its attribution to Xinjiangchelyidae, a clade whose presence has been previously confirmed exclusively from the Middle Jurassic to Early Cretaceous of Asia. We propose that another recently identified taxon from the Iberian Peninsula (i.e., Larachelus morla) is also a member of this clade. Recent studies have identified several continental taxa of the clade that included the members of “Macrobaenidae” and “Sinemydidae” in Europe. This study provides new evidence of close relationships between the Early Cretaceous turtle faunas from Europe and Asia.
Źródło:
Acta Palaeontologica Polonica; 2014, 59, 2; 333-342
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cranial variability of the European Middle Triassic sauropterygian Simosaurus gaillardoti
Autorzy:
Chaves, C.de M.
Ortega, F.
Perez-Garcia, A.
Powiązania:
https://bibliotekanauki.pl/articles/23226.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
Simosaurus is a Triassic eosauropterygian genus known from cranial and postcranial elements, found in the Middle and Upper Triassic strata of Europe and the Middle East. Simosaurus gaillardoti is currently recognised as the only valid species of the genus, identified in Ladinian strata of an area that includes northeastern France (Lorraine) and southwestern Germany (Baden-Württemberg). The remains from this area include more than 20 skulls. Although some of them were described in detail and figured by several authors since the discovery of S. gaillardoti, many others remained unpublished. Here we study and figure 25 skulls from this taxon, reviewing the previously known specimens, and presenting and analyzing numerous unpublished skulls. This significant sample of skulls from a single taxon of a European Triassic eosauropterygian allows us to recognise intraspecific variability in characters previously identified as non-variable in this species, including some that are often included in phylogenetic analyses of these reptiles. Therefore, we markedly increase our knowledge of the cranial skeleton in this taxon.
Źródło:
Acta Palaeontologica Polonica; 2018, 63, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of machining of EN-GJL-250 and EN-GJS-400 cast irons on tribological behavior
Autorzy:
Martinez, J.
Pereira, A.
Perez, J. A.
Mathia, T.
Powiązania:
https://bibliotekanauki.pl/articles/94140.pdf
Data publikacji:
2015
Wydawca:
Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
Tematy:
tribological behavior
grey cast iron
spheroidal graphite cast iron
friction
surface wear
Opis:
In transport and, particularly in the case of the present study, naval industries, one of the major objectives of research on wear and friction is focused principally on solid lubrication. In the following paper, the tribological behaviors of two well-known, different cast irons, lamellar grey iron (EN-GJL-250) and spheroidal graphite ductile iron (EN-GJS-400), are compared and the results are analyzed. For each material's family, the surfaces’ properties are characterized at different stages of the machining process. The particular influence of diverse feed rates in a turning facing is evaluated. Moreover, some tests of the laser cladding process, which contribute to the improvement of superficial properties, are carried out; therefore, the initial morphology before surface treatment is carefully characterized and evaluated in the context of subsequent adhesion qualification. The final goal of the study is to deliver feasible initial information concerning two similar cast irons that are traditionally used in the naval industry, which would be manufactured and employed in the future as dry lubricated bearings
Źródło:
Archives of Mechanical Technology and Materials; 2015, 35; 12-22
2450-9469
Pojawia się w:
Archives of Mechanical Technology and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new freshwater basal eucryptodiran turtle from the Lower Cretaceous of Spain
Autorzy:
Perez-Garcia, A.
De La Fuente, M.S.
Ortega, F.
Powiązania:
https://bibliotekanauki.pl/articles/20420.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new genus
new species
freshwater turtle
eucryptodiran turtle
Lower Cretaceous
Cretaceous
paleontology
Spain
Testudines
Eucryptodira
Barremian
Las Hoyas
Opis:
A freshwater turtle from the lithographic limestone of Las Hoyas (Barremian of Cuenca, Spain) is described as a new genus and species of Eucryptodira, Hoyasemys jimenezi. The holotype consists of the skull, lower jaw, carapace, plastron, vertebral column, pectoral and pelvic girdle remains, and foreand hindlimbs. Hoyasemys jimenezi gen. et sp. nov. is characterized by three pairs of blind oblique depressions on the ventral surface of the basisphenoid, and a character combination composed, among others, of the articulation between the fourth and fifth cervical vertebrae through a cotyle in the fourth and a condyle in the fifth, amphicoelous caudal centra, and most digits of manus and pes with three elongated phalanges. This study allows clarification of the systematic position of a species of uncertain affinity often identified as “chelydroid” in appearance. A phylogenetic analysis shows Hoyasemys jimenezi gen. et sp. nov. forms a monophyletic group with Judithemys sukhanovi, Dracochelys bicuspis, Sinemys lens, and Ordosemys leios, collectively the sister group of crown Cryptodira.
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Importance of the ore veins to study, to interpret and to protect the mining heritage
Znaczenie żył rudnych dla studiowania, interpretacji i ochrony dziedzictwa górniczego
Autorzy:
Dueñas Molina, J.
Lorenc, M. W.
Molina Vega, A.
Molina Molina, F.
Liébanas, J. S.
Pérez Sánchez, A. A.
Powiązania:
https://bibliotekanauki.pl/articles/122205.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
mining heritage
legal protection
cultural landscape
working methodology
dziedzictwo górnicze
ochrona prawna
krajobraz kulturowy
metodologia pracy
Opis:
Four thousand years of mining activity shaped a singular cultural landscape in the Linares-La Carolina district. The geological richness of the area attracted the main civilizations from different eras. Argarians, Romans, Carthaginians, as well as mining companies from Great Britain, Germany, France and Belgium during the industrial period, established their installations working the rich veins of copper and galena. In 2002 the Cultural authorities of the Andalusia Board entrusted the Colectivo Proyecto Arrayanes with a research to identify the most significant remains. The result of our work was the documentation for the inscription of 65 mining and metallurgy sites in the Andalusia Historic Heritage List. Later, we extended the work to a second record including 60 more sites, belonging to all municipalities of the mining district. Currently, our association is developing a project to obtain the certification of the ancien mining district as Heritage Area, a new legal body of the Historical Heritage Law published in Andalucía in 2007. This could provide better protection for the main part of the mining sites and remains in the district, including the archaeological sites. The declaration will allow the management of the territory to became a Cultural Park. Our research establish 16 sectors, extended over eight municipalities. Each sector is related to one or several veins, and includes mining sites, archaeological sites and remains related to metallurgy, ore dressing or railway installations. And each site is described in a registry card. We have catalogued more than 580 sites. Around 150 of them have evidences of the presence of Cornish technology. The Cultural Landscape as axle of future developments and the veins are the real order of the mining territory. Industrial and mining remains, roads, railway lines, etc, are placed in relation with the orientation of the veins. These are the main guidelines of the Working Methodology we are developing to complete this ambitious project.
Cztery tysiące lat działalności górniczej ukształtowało na obszarze Linares-La Carolina swoisty krajobraz kulturowy. Geologiczne bogactwo tego obszaru interesowało główne cywilizacje wszystkich epok. Argarianie, Rzymianie, Kartagińczycy, podobnie jak później wielkie kompanie górnicze z Wielkiej Brytanii, Niemiec, Francji i Belgii w okresie przemysłowym, wszyscy wznosili swoje zakłady pracujące funkcjonujące na bogatych żyłach miedzi i ołowiu. W 2002 r. władze ds. kultury Zarządu Andaluzji powierzyły stowarzyszeniu Colectivo Proyecto Arrayanes wykonanie inwentaryzacji najważniejszych pozostałości górniczych. Rezultatem wykonanej pracy była dokumentacja obejmująca 65 stanowisk górniczych i hutniczych z Listy Andaluzyjskiego Dziedzictwa Historycznego. Później badania poszerzono o drugi zapis kolejnych 60 stanowisk, należących do wszystkich gmin tego górniczego obszaru. Obecnie Stowarzyszenie opracowuje projekt mający na celu deklarację tego dawnego rejonu górniczego jako Obszar Dziedzictwa, nową postać prawną Dziedzictwa Historycznego stworzoną w Andaluzji w 2007 r. Mogłoby to zapewnić lepszy poziom ochrony głównej części terenów górniczych, ale też pozostałego obszaru, w tym stanowisk archeologicznych. Deklaracja taka umożliwiłaby zarządzanie tym terytorium jako Parkiem Kultury. Przedstawiona propozycja ustanawia 16 obszarów, poszerzonych o osiem gmin. Każdy obszar związany jest z jedną lub kilkoma żyłami rudnymi i obejmuje stanowiska górnicze, archeologiczne oraz pozostałości związane z metalurgią, przeróbką rudy i obiekty kolejowe. Każde stanowisko opisane jest w formie oddzielnej karty kartoteki rejestru. Stworzony katalog obejmuje ponad 560 stanowisk, z których około 150 posiada dowody wykorzystywania technologii kornwalijskiej. Krajobraz kulturowy oraz rudne żyły stanowią oś przyszłego rozwoju terytorium górniczego. Pozostałości przemysłowe i górnicze, drogi, linie kolejowe itp., są umieszczone w stosunku do orientacji żyły. Właśnie one są głównymi wytycznymi do stworzenia roboczej metodologii, opracowywanej w celu ukończenia tego ambitnego projektu.
Źródło:
Hereditas Minariorum; 2018, 5; 33-50
2391-9450
2450-4114
Pojawia się w:
Hereditas Minariorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of the soil water content on Jatropha seedlings in a tropical climate
Autorzy:
Perez-Vazquez, A.
Hernandez-Salinas, G.
Avila-Resendiz, C.
Valdes-Rodriguez, O.A.
Gallardo-Lopez, F.
Garcia-Perez, E.
Ruiz-Rosado, O.
Powiązania:
https://bibliotekanauki.pl/articles/25415.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Opis:
The purpose of this study was to evaluate growth, chlorophyll content, and photosynthesis in Jatropha at different levels of soil moisture. Plants were cultivated in containers and the treatments of the soil water content evaluated were: 0% (without watering), 20, 40, 60, and 80% soil water content. Plant height was statistically similar for all treatments, but the number of leaves differed significantly. Total dry matter and chlorophyll at 40, 60, and 80% soil water content were statistically similar, but different from 0 and 20% soil water content. Leaf area at 40, 60, and 80% soil water content was statistically different from 0 and 20% soil water content. The photosynthetic rate, transpiration and stomatal conductance at 60 and 80% soil water content were statistically similar but different from 0 and 20% soil water content. Water stress affected growth, chlorophyll content, photosynthetic rate, transpiration, and stomatal conductance.
Źródło:
International Agrophysics; 2013, 27, 3
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Blood lead determinants and the prevalence of neuropsychiatric symptoms in firearm users in Mexico
Autorzy:
Aguilar Madrid, Guadalupe
Téllez-Cárdenas, Liliana
Juárez-Pérez, Cuauhtémoc A.
Haro-García, Luis C.
Mercado-García, Adriana
Gopar-Nieto, Rodrigo
Cabello-López, Alejandro
Powiązania:
https://bibliotekanauki.pl/articles/2177065.pdf
Data publikacji:
2015-11-12
Wydawca:
Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
Tematy:
neuropsychiatric symptoms
occupational exposure
lead exposure
blood lead
firearms
heavy metal toxicity
Opis:
Objectives To identify blood lead predictors and the prevalence of neuropsychiatric symptoms in firearm users of public security in Mexico. Material and Methods A cross-sectional study was performed on 65 males. We obtained socio-occupational data and determined venous blood lead (blood (B), lead (Pb) – BPb), as well as neuropsychiatric symptoms using the Q-16 questionnaire. A multiple linear regression model was constructed to assess determinants of BPb. Results The mean age in the study group was 34.8 years (standard deviation (SD) = 6.9, range: 21–60); the mean number of years spent in the company amounted to 14 years (SD = 8.5, range: 1–48). Twenty percent of the respondents (N = 13) used leaded glazed clay pottery (lead (Pb), glazed (G), and clay pottery (C) – PbGC) in the kitchen. During practice they fired a mean of 72 shots (SD = 60, range: 20–250), and during their whole duration of employment 5483 shots (SD = 8322.5, range: 200–50 000). The mean BPb was 7.6 μg/dl (SD = 6.8, range: 2.7–51.7). Two caretakers from the firing range had 29.6 μg/dl and 51.7 μg/dl BPb. The subjects who had shooting practice sessions ≥ 12 times a year reported a greater percentage of miscarriages in their partners (24% vs. 0%). Twelve percent of the respondents showed an increase in neuropsychiatric symptoms. The BPb multiple linear regression model explained R² = 44.15%, as follows: those who had ≥ 12 practice sessions per year – β = 0.5339 and those who used PbGC – β = 0.3651. Conclusions Using firearms and PbGC contributes to the increased BPb in the studied personnel. The determinants of BPb were: shooting practices >12 times a year and using PbGC. Blood lead concentrations reported in the study, despite being low, are a health risk, as evidenced by the prevalence of neuropsychiatric symptoms.
Źródło:
International Journal of Occupational Medicine and Environmental Health; 2016, 29, 2; 219-228
1232-1087
1896-494X
Pojawia się w:
International Journal of Occupational Medicine and Environmental Health
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The oldest post-Paleozoic (Ladinian, Triassic) brachiopods from the Betic Range, SE Spain
Autorzy:
Baeza-Carratala, J.F.
Perez-Valera, F.
Perez-Valera, J.A.
Powiązania:
https://bibliotekanauki.pl/articles/22178.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
Triassic brachiopods from the Betic Range were unknown hitherto. Herein we describe the first brachiopod occurrences in the early Ladinian of this domain referable to a new genus and species Misunithyris goyi derived from three localities of the south-Iberian Triassic outcrops. The analysis of internal and external characters of this brachiopod allowed to characterize systematically and biogeographically this fauna in a chronostratigraphic interval when the paucity of brachiopod records is attributable to the entire peri-Iberian epicontinental platform system established in the westernmost Tethyan margin. The new record is endemic to the Betic Range and represents a new faunal constituent of the multicostate zeillerids stock. This fauna inhabited the epicontinental seas of the Sephardic bioprovince since a closer affinity with the low-latitude Tethyan assemblages is revealed. The possible linkage of the Triassic stock with the Early–Middle Jurassic multicostate zeillerid representatives suggests feasible phylogenetic relationships between both groups.
Źródło:
Acta Palaeontologica Polonica; 2018, 63, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Temperature increase associated with plastic deformation under dynamic compression: application to aluminium alloy AL 6082
Wzrost temperatury wywołany plastycznym odkształceniem przy dynamicznym ściskaniu – analiza stopu aluminium Al 6082
Autorzy:
Perez-Castellanos, J.-L.
Rusinek, A.
Powiązania:
https://bibliotekanauki.pl/articles/280469.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
infrared thermography
plastic strain
adiabatic heating
Hopkinson bar
Opis:
The temperature increase associated with plastic deformation of a material under loading may be measured using several techniques such as infrared thermography (IRT). The present work investigates the temperature increase at different high strain rates and initial test temperatures, using an aluminium alloy Al 6082. A Split Hopkinson Pressure Bar (SHPB) was applied to induce high strain rates to the material and an infrared camera was used to measure the temperature increase. Numerical simulations of dynamic tests were performed to calculate the temperature increase and to gain a better understanding of the process by local measurements. Thus, a detailed finite-elements model was developed to simulate the dynamic compression test. The fraction of plastic work converted into heat was estimated using the Zehnder model. Numerical results in terms of the strain rate and initial temperature effect on the material temperature increase are reported and compared with experiments.
Wzrost temperatury w materiale związany z plastycznym odkształcaniem może być rejestrowany różnymi metodami, w tym m.in. techniką termografii podczerwieni (IRT). Prezentowana praca poświęcona jest badaniom wzrostu temperatury przy różnym tempie odkształceń i temperatury początkowej próbek wykonanych ze stopu aluminium Al 6082. W eksperymentach użyto zmodyfikowanego pręta Hopkinsona do generowania szybko-zmiennych odkształceń w materiale i jednocześnie dokonywano pomiarów temperatury za pomocą kamery termowizyjnej. Przeprowadzono także symulacje numeryczne przebiegu przyrostu temperatury pozwalające na lepsze zrozumienie zachodzących procesów na podstawie lokalnych pomiarowym. W tym celu zbudowano szczegółowy model bazujący na metodzie elementów skończonych, który przeanalizowano pod kątem dynamicznego ściskania. Część pracy odkształcenia plastycznego zamienianego w ciepło oszacowano za pomocą modelu Zehndera. Wyniki obliczeń uwzględniających tempo odkształceń i temperaturę początkową na jej przyrost w badanym materiale zweryfikowano z rezultatami doświadczeń.
Źródło:
Journal of Theoretical and Applied Mechanics; 2012, 50, 2; 377-398
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamism patterns of western Mediterranean cruise ports and the coopetition relationships between major cruise ports
Autorzy:
Esteve-Perez, J.
Garcia-Sanchez, A.
Powiązania:
https://bibliotekanauki.pl/articles/258786.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
cruise ports
Mediterranean ports
hierarchic patterns
coopetition
shift-share analysis
Opis:
The Mediterranean Sea has seen an increase of ports hosting cruise ships during the first fifteen years of the 21st century. The increase in cruise ship presence in Mediterranean ports is associated with the dynamism of cruise traffic in recent years, with an average annual growth of 7.45% for cruise passengers worldwide during the period of 1990-2015. Cruise traffic is a maritime business that is primarily composed of two elements, maritime affairs and tourism. This article focuses on the maritime component. With the growth of the cruise industry, cruise lines have been forced to seek new ports to meet demand in an attempt to create differentiated products based on the ports that compose the itinerary. The itinerary system of cruise traffic makes the cruise ports depend on one another to design an itinerary. This feature results in both complex geographic relationships in the design of a cruise itinerary and complex competitive/cooperative relationships between ports. The aim of this article is to present the hierarchic picture of a sample of 29 cruise ports in the Western Mediterranean region during the period of 2000-2015. To achieve this goal, a port size classification is proposed and a shift-share analysis at the inter- and intra-group size level is applied. Moreover, concentration measures are used to determine the changes in the levels of market concentration. Furthermore, a dynamic model is proposed to determine the competitive or cooperative relationships between cruise ports. The proposed model is applied to the largest ports with data from the 2001-2015 period.
Źródło:
Polish Maritime Research; 2018, 1; 51-60
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparison of hole-filling methods in 3D
Autorzy:
Pérez, E.
Salamanca, S.
Merchán, P.
Adán, A.
Powiązania:
https://bibliotekanauki.pl/articles/331035.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
3D polygonal model
repairing meshes
hole filling
restoration algorithm
model wielokątny 3D
renowacja siatki
algorytm renowacji
Opis:
This paper presents a review of the most relevant current techniques that deal with hole-filling in 3D models. Contrary to earlier reports, which approach mesh repairing in a sparse and global manner, the objective of this review is twofold. First, a specific and comprehensive review of hole-filling techniques (as a relevant part in the field of mesh repairing) is carried out. We present a brief summary of each technique with attention paid to its algorithmic essence, main contributions and limitations. Second, a solid comparison between 34 methods is established. To do this, we define 19 possible meaningful features and properties that can be found in a generic hole-filling process. Then, we use these features to assess the virtues and deficiencies of the method and to build comparative tables. The purpose of this review is to make a comparative hole-filling state-of-the-art available to researchers, showing pros and cons in a common framework.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2016, 26, 4; 885-903
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
s,p-d Exchange Constants of CdFeSe Semimagnetic Semiconductor
Autorzy:
Arciszewska, M.
Pakuła, K.
Perez, I.
Twardowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/1886791.pdf
Data publikacji:
1991-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.25.Tn
71.70.Gm
71.35.+z
Opis:
We report determination of s, p-d exchange constants for hexagonal CdFeSe combining exciton splitting and magnetization measurements performed on the same samples.
Źródło:
Acta Physica Polonica A; 1991, 79, 2-3; 345-348
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Latitude error in compass deviation. Mathematical method to determine the latitude error in magnetic compass deviation
Autorzy:
Basterretxea, I. I.
Vila- Muñoz, J. A.
Perez -Labajos, C. A.
Powiązania:
https://bibliotekanauki.pl/articles/258974.pdf
Data publikacji:
2014
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
optimal exact coefficients
average deviation
latitude error
Opis:
This article aims to provide the seafarer with a tool to calculate the deviation for a righted ship in any geographical position using only the information available on board. In this way the accidental errors in the deviation card are reduced and the latitude error is made negligible. Moreover, an experimental application of this method is carried out on board a tanker to compare the latitude error in different positions at sea.
Źródło:
Polish Maritime Research; 2014, 3; 25-31
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mg-Phosphate Ceramics Produced from the Product of Thermal Transformation of Cement-Asbestos
Magnezowo-fosforanowe wyroby ceramiczne wytwarzane z produktów termicznej transformacji cementu - azbestów
Autorzy:
Perez-Estebanez, M.
Macova, P.
Sasek, P.
Viani, A.
Gualtieri, A.
Powiązania:
https://bibliotekanauki.pl/articles/317820.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
cement-asbestos
magnesium phosphate ceramics
amorphous
cement-azbest
magnez
fosforyty ceramiczne
bezpostaciowość
Opis:
According to recent European directives, the need for environmentally friendly alternative solutions to landfill disposal of hazardous wastes, such as asbestos-containing materials, prompts their recycling as secondary raw materials. In this work, magnesium phosphate ceramics were prepared using the product of inertization of cement-asbestos. Magnesium phosphate ceramics show interesting properties like good water resistance and high strength that make them attractive materials for several applications. Asbestos containing materials were mixed with magnesium carbonate and annealed at two different temperatures (1100 and 1300 ºC). During thermal treatment complete destruction of asbestos minerals with their transformation into new phases, and crystallization of MgO from magnesium carbonate decomposition, occurs. Upon addition of potassium di-hydrogen phosphate and water, the magnesium oxide in the product of thermal treatment, contributes to the onset of a setting reaction whose product is magnesium potassium phosphate hydrate. The reactivity of periclase was found to be dependent on the calcination temperature. Lower reaction rates were observed for the MgO obtained at lower temperature. The setting reaction of the magnesium phosphate ceramic has been followed in time up to 6 months by means of the X-rays powder diffraction trechnique. Quantitative phase analysis was performed using the Rietveld method and both crystalline and amorphous phases were quantified. The amount of magnesium potassium phosphate was found to increase with time, and was accompained by a decrease in the amount of the amorphous fraction. This fact supports the hypothesis of the formation of an amorphous precursor of the crystalline MKP during the hydration reaction. SEM images showing elongated magnesium potassium phosphate hydrate crystals emerging from what appears as an amorphous matrix, further confirms this view. Since the mechanical properties of magnesium phosphate ceramics are known to increase with time, we can conclude that the main contribution to the development of strenght comes from the crystalline magnesium potassium phosphate hydrate. In this work, we describe a procedure for simultaneous destruction of asbestos minerals and formation of cementitious compounds, which represents a recycling opportunity for this class of hazardous wastes, bringing benefits in terms of energy requirements and preservation of natural resources in cement manufacturing.
Zgodnie z niedawnymi dyrektywami europejskimi, potrzeba przyjaznego dla środowiska alternatywnego rozwiązania usuwania odpadów niebezpiecznych, takich jak materiałów zawierających azbest, pobudza ich ponowne wykorzystanie jako surowców wtórnych. W tej pracy, magnezowo fosforanowe wyroby ceramiczne zostały wytworzone z użyciem produktów inertyzacji cementu – azbestu. Magnezowo fosforanowe wyroby ceramiczne wykazują interesujące właściwości takie jak dobry opór wodny oraz duża wytrzymałość, co sprawia, że są atrakcyjnym materiałem dla wielu aplikacji. Materiały zawierające azbest zostały zmieszanie w węglanem magnezu i wyżarzone w dwóch różnych temperaturach (1100°C i 1300°C). Podczas obróbki cieplnej następuje całkowite zniszczenie minerałów azbestu wraz z ich transformacją w nowe fazy, oraz krystalizacja MgO z rozpadu węglanu magnezu. Podczas dodawania diwodorofosforanu magnezu do wody, tlenek magnezu jako produkt obróbki cieplnej, przyczynia się do rozpoczęcia reakcji wiązania, której produktem jest hydrat fosforanu magnezu i potasu. Odkryto, że reaktywność peryklazu zależy od temperatury kalcynacji. Niższa szybkość reakcji została zaobserwowana dla MgO uzyskanego w niższej temperaturze. Reakcja wiązania wyrobów ceramicznych magnezowo fosforanowych została przeprowadzona w czasie do 6 miesięcy za pomocą techniki rentgenowskiej dyfrakcji proszkowej. Ilościowe analizy fazowe zostały wykonane z użyciem metody Rietvelda i obliczono zarówno fazę krystaliczną jak i amorficzną. Zauważono, że ilość fosforanu magnezowo potasowego zwiększa się w czasie, i że towarzyszy jej spadek ilości części amorficznej. Fakt ten potwierdza hipotezę powstawania amorficznego prekursora krystalicznego fosforanu magnezowo potasowego podczas reakcji hydracji. Obrazy SEM przedstawiają wydłużone kryształy hydratu fosforanu magnezowo potasowego wyłaniające się, z wyglądającej na amorficzną, macierzy, następnie ten wygląd się potwierdza. Ponieważ wiadomo, że właściwości mechaniczne fosforanu magnezu zwiększają się z czasem, możemy wnioskować, że główny wpływ na zwiększenie się wytrzymałości ma krystaliczny hydrat fosforanu magnezowo potasowego. W pracy tej opisano procedurę jednoczesnego rozpadu minerałów azbestu i tworzenia się związków cementytowych, co wskazuje na możliwość powtórnego przetworzenia tego rodzaju odpadów niebezpiecznych, co przynosi korzyści w kategoriach zapotrzebowania energetycznego i ochrony zasobów naturalnych w przetwórstwie cementu.
Źródło:
Inżynieria Mineralna; 2014, R. 15, nr 2, 2; 187-192
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An integrated approach to understanding the role of the long neck in plesiosaurs
Autorzy:
NOÈ, LESLIE F.
TAYLOR, MICHAEL A.
GÓMEZ-PÉREZ, MARCELA
Powiązania:
https://bibliotekanauki.pl/articles/945290.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
sauropterygia
plesiosauria
long neck
functional anatomy
filter feeding
palaeoecology
evolution
Opis:
The evolution and function of the long neck in plesiosaurs, and how the problems associated with stiffness or flexibility were overcome during feeding, or rapid swimming during predator avoidance, are explored, and a new interpretation for the function of the plesiosaur neck is presented. Based on the anatomy of the articular faces of contiguous cervical vertebral centra, neural arches, and cervical ribs, the plesiosaur neck was mainly adapted for ventral bending, with dorsal, lateral and rotational movements all relatively restricted. Predominant ventral bending indicates the neck was adapted for use beneath the body, suggesting feeding in the water column, close to the sea floor, or within soft sediments on the sea floor. A new model is proposed for the plesiosaur bauplan, comprising the head as a filter, straining, sieve feeding or sediment raking apparatus, mounted on a neck which acted as a stiff but ventrally flexible feeding tube, attached to the body which acted as a highly mobile feeding platform. Numerous features of plesiosaurs, including cranial and dental form, cervical vertebral morphology, body shape and limb-based propulsion, conform to this model. Comparative data from modern organisms support this novel explanation for the structure and function of the plesiosaur long neck. This integrative analysis offers an explanation for the evolution of the plesiosaur long neck as a key evolutionary novelty, and why this apparently enigmatic feature remained a prominent feature of plesiosaurs throughout their long evolutionary history.
Źródło:
Acta Palaeontologica Polonica; 2017, 62, 1; 137-162
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The identification of heavy metal accumulator ferns in abandoned mines in the Philippines with applications to mine rehabilitation and metal recovery
Autorzy:
Claveria, Rene Juna R.
Perez, Teresita R.
Navarrete, Ian A.
Perez, Rubee Ellaine C.
Lim, Brian Christian C.
Powiązania:
https://bibliotekanauki.pl/articles/1839051.pdf
Data publikacji:
2020
Wydawca:
Główny Instytut Górnictwa
Tematy:
hyperaccumulator ferns
mine rehabilitation
phytoremediation
phytomining
paprocie hiperakumulacyjne
rekultywacja kopalni
fitoremediacja
fitogórnictwo
Opis:
This paper focuses on the identification of some plant accumulators of heavy metals that can facilitate mine remediation and rehabilitation in the Philippines and metal recovery or phytomining. Most of these hyperaccumulators are ferns that thrive very well in different terrains and of particular interest are Pityrogramma calomelanos, Pteris vittata, and Pteris melanocaulon that are abundant in abandoned CueAu mining areas. The amounts of Cu and As in the soil and in the aboveground (AG) and belowground (BG) components of the accumulator ferns were determined and the Bioaccumulation Factor (BF) and the Translocation Factor (TF) were derived. Efforts to propagate the accumulator ferns identified from spores were successful, thus providing the opportunity of using them for various experiments on mine rehabilitation and metal recovery. The results of these experiments indicated that these hyperaccumulator ferns have the greatest potential for the remediation of metal contaminated soils, the rehabilitation of abandoned mines, and phytomining.
Źródło:
Journal of Sustainable Mining; 2020, 19, 1; 46-57
2300-1364
2300-3960
Pojawia się w:
Journal of Sustainable Mining
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acoustic Scattering of 3D Complex Systems Having Random Rough Surfaces by Scalar Integral Equations
Autorzy:
Guel-Tapia, J. A.
Villa-Villa, F.
Mendoza-Suárez, A.
Pérez-Aguilar, H.
Powiązania:
https://bibliotekanauki.pl/articles/178120.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
integral equations
Helmholtz equation
acoustic scattering
Opis:
We propose a numerical surface integral method to study complex acoustic systems, for interior and exterior problems. The method is based on a parametric representation in terms of the arc’s lengths in curvilinear orthogonal coordinates. With this method, any geometry that involves quadric or higher order surfaces, irregular objects or even randomly rough surfaces can be considered. In order to validate the method, the modes in cubic, spherical and cylindrical cavities are calculated and compared to analytical results, which produced very good agreement. In addition, as examples, we calculated the scattering in the far field and the near field by an acoustic sphere and a cylindrical structure with a rough cross-section.
Źródło:
Archives of Acoustics; 2016, 41, 3; 461-472
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
DVB-T Channels Measurements for the Deployment of Outdoor REM Databases
Autorzy:
Kliks, A.
Kryszkiewicz, P.
Cichoń, K.
Umbert, A.
Perez-Romero, J.
Casadevall, F.
Powiązania:
https://bibliotekanauki.pl/articles/307830.pdf
Data publikacji:
2014
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
channel measurements
DVB-T
spectrum occupancy
Radio Environment Maps
Opis:
In this paper the analysis of the spectrum occupancy in the TV band is provided based on the outdoor measurements campaigns carried out in Poznań, Poland in 2013 and 2014. The goal of this work is to discuss the stability and other important features of the observed spectrum occupancy in the context of outdoor Radio Environment Maps database deployment. Reliable deployment of these databases seems to be one of the critical points in practical utilization of the TV White Spaces for cognitive purposes inside buildings and in densely populated cities. The results obtained for outdoor scenario are briefly compared with the previous measurements conducted indoors in Barcelona, Spain, and in Poznań, Poland.
Źródło:
Journal of Telecommunications and Information Technology; 2014, 3; 42-52
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aerobiological study in east - central iberian peninsula: pollen diversity and dynamics for major taxa
Autorzy:
Perez-Badia, R.
Rapp, A.
Vaquero, C.
Fernandez-Gonzalez, F.
Powiązania:
https://bibliotekanauki.pl/articles/50584.pdf
Data publikacji:
2011
Wydawca:
Instytut Medycyny Wsi
Źródło:
Annals of Agricultural and Environmental Medicine; 2011, 18, 1
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Temperature effects on the parametric generation in a water-filled acoustical resonator
Autorzy:
Pérez-Arjona, I.
Cebrecos, A.
Sánchez-Morciillo, V. J.
Espinosa, V.
Powiązania:
https://bibliotekanauki.pl/articles/332260.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
We consider the problem of parametric sound generation in an acoustic interferometer containing a fluid. We have taken explicitly into account both the influence of the nonlinearly generated second harmonic and the effect of the unavoidable rising of the temperature due to the acoustic wave. Two main new features under these considerations can be observed. On one hand, the fundamental field does not achieve a saturating value when subharmonics fields appear, but still grows with the driving. On the other hand, the subharmonics fields can exist only for a limited range of driving value, due to the dependence of the cavity resonances with the temperature of the medium. The experimental setup was designed and we show here the experimental measurements, which are in good agreement with the predicted values for the mode amplitudes and the parametric threshold.
Źródło:
Hydroacoustics; 2013, 16; 197-202
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Non-Polar ZnO Layers with Positron Annihilation Spectroscopy
Autorzy:
Zubiaga, A.
Tuomisto, F.
Zúñiga-Pérez, J.
Muñoz-San José, V.
Powiązania:
https://bibliotekanauki.pl/articles/1811964.pdf
Data publikacji:
2008-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.uj
68.55.Ln
68.37.-d
78.70.Bj
Opis:
We applied positron annihilation spectroscopy to study the effect of growth polarity on the vacancy defects in ZnO grown by metal-organic vapor phase deposition on sapphire. Both c-plane and a-plane ZnO layers were measured, and Zn vacancies were identified as the dominant defects detected by positrons. The results are qualitatively similar to those of earlier experiments in GaN. The Zn vacancy concentration decreases in c-plane ZnO by almost one order of magnitude (from high $10^{17} cm^{-3}$ to low $10^{17} cm^{-3}$) when the layer thickness is increased from 0.5 to 2 μm. Interestingly, in a-plane ZnO the Zn vacancy concentration is constant at a level of about $2×10^{17} cm^{-3}$ in all the samples with thicknesses varying from 0.6 to 2.4 μm. The anisotropy of the Doppler broadening of the annihilation radiation parallel and perpendicular to the hexagonal c-axis was also measured.
Źródło:
Acta Physica Polonica A; 2008, 114, 5; 1257-1264
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Catechins from Smilax domingensis Willd. in Cuba
Autorzy:
Soledispa, Pilar A.
González, José
Cuéllar, Armando
Pérez, Julio
Monan, Max
Powiązania:
https://bibliotekanauki.pl/articles/1077467.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
GC/MS
Smilax domingensis
catechins
ethanolic extract
flavanols
Opis:
Gas Chromatography coupled with mass spectrometry was applied to study the fragmentation of selected flavonoids from the ethanolic extract of Smilax domingensis Willd., Smilacaceae, known as zarzaparrilla, after Soxhlet extraction during 20 hours. Compounds belonging to one of the major subgroups found in common plants, i.e. flavanols were studied. Following solvent extraction and derivatization using BSTFA, possibly two different metabolites from the same chemical group were characterized in one analytical run: (+)-catechin and (-)-epicatechin. For the very first time, qualitative data on these analytes in the drug were determined after detailed validation of a sensitive, cheap and reliable GC-MS method.
Źródło:
World News of Natural Sciences; 2019, 23; 297-305
2543-5426
Pojawia się w:
World News of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Secondary electron interactions in materials with environmental and radiological interest
Autorzy:
García, G.
Blanco, F.
de Pablos, J.
Pérez, J.
Williart, A.
Powiązania:
https://bibliotekanauki.pl/articles/148529.pdf
Data publikacji:
2003
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
electron scattering
energy deposition
Opis:
Important environmental and radiological applications require energy deposition models including the interactions between the secondary electrons and the atoms or molecules of the medium. In this work we propose a method to obtain reliable cross-section data to be used in these models by combining total and ionisation cross-section measurements with simple calculations of the differential and integral elastic cross sections. The energy loss spectra obtained in this experiment have been also used to derive the stopping power of the considered materials for electrons. Some examples of results for atomic (Xe) and molecular (CF4) targets are presented and discussed in this paper.
Źródło:
Nukleonika; 2003, 48, 2; 103-107
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stability of Bilayer Superconductors against Thermomagnetic Avalanche
Autorzy:
Vasiliev, S.
Chumak, O.
Chabanenko, V.
Pérez-Rodríguez, F.
Nabiałek, A.
Powiązania:
https://bibliotekanauki.pl/articles/1374778.pdf
Data publikacji:
2014-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.Op
74.72.-h
74.25.Sv
Opis:
The problem of stability of bilayer type II superconductor with different critical current densities of inner part and coating was considered. The optimum thickness of surface layer enabling the maximal increase of the field of first flux jump was found. The field of instability for such bilayer structure was calculated for NbTi superconductor. An increase of the field of the first flux jump by about 60% has been found for optimal coating thickness.
Źródło:
Acta Physica Polonica A; 2014, 126, 4a; A-84-A-87
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Branching system of the Mexican hawthorn “Tejocote” (Crataegus spp.)
Autorzy:
Perez-Ortega, S.A.
Mendez-Santiago, A.H.
Nieto-Angel, R.
Jankiewicz, L.S.
Powiązania:
https://bibliotekanauki.pl/articles/2039.pdf
Data publikacji:
2013
Wydawca:
Instytut Ogrodnictwa
Tematy:
edible hawthorn
Mexican hawthorn
fruit tree
Crataegus
canopy architecture
branching system
inflorescence
morphological diversity
Źródło:
Journal of Horticultural Research; 2013, 21, 1
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Body mass estimation in amphicyonid carnivoran mammals: A multiple regression approach from the skull and skeleton
Autorzy:
Figueirido, B.
Perez-Claros, J.A.
Hunt, R.M.Jr.
Palmqvist, P.
Powiązania:
https://bibliotekanauki.pl/articles/21366.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
body mass
estimation
amphicyonid
mammal
skull
skeleton
Mammalia
Carnivora
Amphicyonidae
multiple regression
paleontology
Opis:
The body masses of sixteen species of amphicyonids (Mammalia, Carnivora, Amphicyonidae) from the New and Old World were estimated on the basis of 86 osteological variables measured from the craniodental (N = 44) and postcranial (N = 42) skeleton of living species of Canidae and Ursidae. Given the absence of complete and well preserved skeletons of amphicyonids in the fossil record, multiple regression functions were derived separately from measurements taken from the mandible, the cranium and the major limb bones. The accuracy of the regression functions was evaluated using the percentage prediction error and the percentage standard error of the estimates. Mass values were calculated with these equations using measurements taken in adult individuals from a number of daphoenine and amphicyonine species. Results obtained show that three distinct size classes of amphicyonids emerged through the evolutionary history of the “beardog” family and that these size classes correlate with presumably different ecomorphs. Quantitative estimates of body size of amphicyonids are critical for deciphering the paleobiology of this poorly understood family of large fissiped carnivorans and can be used for placing it within a broader ecological context.
Źródło:
Acta Palaeontologica Polonica; 2011, 56, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
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:
The acute bacterial toxicity of the selenocyanate anion and the bioprocessing of selenium by bacterial cells
Autorzy:
Montes, R. A.
Pradenas, G. A.
Pérez-Donoso, J. M.
Vásquez, C. C.
Chasteen, T. G.
Powiązania:
https://bibliotekanauki.pl/articles/363098.pdf
Data publikacji:
2012
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
bioremediacja
selenowe aniony tlenowe
SeCN
SeO3
SeO4
bioremediation
selenium oxyanions
Opis:
A water-soluble anion containing selenium, selenocyanate (SeCN-), is produced in various industrial settings including petrochemical refining and mining wastewaters and is difficult to remove using common chemical or physical processes. The work described was aimed at determining the relative acute toxicity of SeCNby evaluating its minimal inhibitory and minimal bactericidal concentrations for 1) a bacterium (LHVE) that produces volatile selenium-containing derivatives in cultures containing added SeCNand 2) for a sensitive E. coli wild-type strain. These measures of toxicity were compared to those of selenate and selenite, the oxyanions of selenium commonly found in the environment. Cultures of LHVE amended with SeCNon agar plates produced red, elemental selenium after three days. As far as we know this is the first evidence for the biological production of elemental Se by a metalloid-resistant bacterium exposed to selenocyanate. Bioprocessing of selenite and SeCNby both types of bacteria, as analyzed by inductively coupled plasma spectrometry, demonstrated that LHVE more successfully incorporates or precipitates Se compared to E. coli.
Źródło:
Environmental Biotechnology; 2012, 8, 1; 32-38
1734-4964
Pojawia się w:
Environmental Biotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermodynamic Analysis of the Graphite Flake Formation of Low Manganese and Sulfur Gray Cast Iron
Autorzy:
Reyes-Castellanos, G.
Cruz-Ramírez, A.
Colin-García, E.
Gutiérrez-Pérez, V. H.
Powiązania:
https://bibliotekanauki.pl/articles/2049436.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
gray iron
inoculation
cell count
thermodynamic analysis
Opis:
Low manganese and sulfur gray irons were produced by adding inoculant base Fe-Si with small amounts of Al and Ca in the ladle. The effect of the cast thickness, inoculant amount and shakeout time of the green sand molds were studied on the graphite flake formation by microscopically techniques. A thermodynamic analysis was carried out for the cast iron produced with the FactSage 7.2 software. Stability phase diagrams were obtained for both gray cast irons to different manganese (0.1 to 0.9 wt.%) and sulfur (0.01 to 0.12 wt.%) amounts to 1150°C. It was shown that lower amounts of manganese and sulfur allow forming the 3Al2O3·2SiO2, Al2O3, and ZrO2 solid compounds. The thermodynamic results match with those obtained by SEM-EDS. It is possible to form MnS particles in the liquid phase when the solubility product (%Mn) × (%S) equals 0.042 and 0.039 for heats A and B, respectively.
Źródło:
Archives of Metallurgy and Materials; 2021, 66, 1; 249-258
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polyphenolic composition of Spanish cultivars of globe artichoke (Cynara cardunculus L. var. scolymus (L.) Fiori)
Autorzy:
Pérez-Esteve, É.
Sałata, A.
Barat, J.M.
Stępniowska, A.
López-Galarza, S.
Nurzyńska-Wierdak, R.
Powiązania:
https://bibliotekanauki.pl/articles/11897335.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Przyrodniczy w Lublinie. Wydawnictwo Uniwersytetu Przyrodniczego w Lublinie
Tematy:
plant cultivation
cardoon
Cynara cardunculus
polyphenolic composition
Opal cultivar
Concerto cultivar
Symphony cultivar
Madrigal cultivar
Blanca de Tudela cultivar
A-106 cultivar
herbal plant
medicinal plant
phenolics content
chlorogenic acid
apigenin
cynarin
Opis:
Globe artichoke (Cynara cardunculus L. var. scolymus (L.) Fiori) is an edible herbaceous perennial plant that plays an important economic role in Mediterranean agriculture. In recent years, extensive research, which aimed to characterize the phenolic profile of the most important globe artichoke cultivars in Italy, has been conducted. However, very little information is available on the phenolic composition of cultivars traditionally grown in Spain. In this work, six cultivars (‘Opal’, ‘Symphony’, ‘Concerto’, ‘Madrigal’, ‘Blanca de Tudela’ and ‘A-106’) cultured in Spain were characterized according to their phenolic content. The phenolic profile differed between cultivars, and also between flower parts. The major phenolic compound in all the different cultivars was chlorogenic acid. Of the six studied cultivars, ‘Madrigal’ had the highest phenolic content.
Źródło:
Acta Scientiarum Polonorum. Hortorum Cultus; 2018, 17, 2; 177-184
1644-0692
Pojawia się w:
Acta Scientiarum Polonorum. Hortorum Cultus
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Influence of Magnetic History on the Stability of Critical State and the Dynamics of Flux Jumps in Conventional NbTi Superconductor
Autorzy:
Nabiałek, A.
Vasiliev, S.
Chabanenko, V.
Perez-Rodriguez, F.
Piechota, S.
Szymczak, H.
Powiązania:
https://bibliotekanauki.pl/articles/1537035.pdf
Data publikacji:
2010-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.Ad
74.25.Sv
Opis:
We studied the influence of magnetic history on the stability of critical state and the dynamics of flux jumps in conventional NbTi superconductor. We have found that both the stability of critical state and the dynamics of flux jumps are strongly influenced by the magnetic history and by the magnetic field distribution induced within the sample by preceding jumps. This magnetic field distribution can be particularly complex in the region of the hysteresis loop where the external magnetic field changes its sign (region of remagnetization), because of demagnetizing effects. For this reason, the most complex structure of the flux jumps is observed in the third quadrant of magnetization hysteresis loop. Flux jumps observed in the region of remagnetization have different dynamics in comparison to the jumps observed in other regions of the magnetization hysteresis loop. Duration of these jumps is usually significantly longer than others, and their structure is more complex.
Źródło:
Acta Physica Polonica A; 2010, 118, 2; 343-345
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Endophytic colonisation of tomato by the entomopathogenic fungus Beauveria bassiana: the use of different inoculation techniques and their effects on the tomato leafminer Tuta absoluta (Lepidoptera: Gelechiidae)
Autorzy:
Allegrucci, N.
Velazquez, M.S.
Russo, M.L.
Perez, E.
Scorsetti, A.C.
Powiązania:
https://bibliotekanauki.pl/articles/65417.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
endophytic fungi
tomato
entomopathogen
fungi
Beauveria bassiana
inoculation method
tomato leafminer
Tuta absoluta
Lepidoptera
Gelechiidae
biological control
Solanum lycopersicum
Opis:
Fungal entomopathogens can naturally regulate populations of various insects. The entomopathogen Beauveria bassiana (Bals.- Criv.) Vuill. is also able to endophytically colonize different plants. Endophytic colonization by entomopathogens may provide a source of indirect interactions between fungi and insects and has been associated with the ability of the fungus to control insect pests. The tomato leaf miner, Tuta absoluta (Meyrick) is considered one of the most devastating pests of tomato (Solanum lycopersicum L.) and its difficult control is due to its miner habit, short life cycle, and high reproductive capacity. The aims of this study were: (i) to use three different techniques, i.e. leaf spraying, seed immersion and root dipping, for the endophytic inoculation of B. bassiana in tomato plants; and (ii) to assess the effect of B. bassiana on tomato leaf consumption and mortality of T. absoluta after inoculation. The percentage of colonization by B. bassiana was assessed 7, 14 and 28 days after inoculation. All inoculation techniques employed allowed the recovery of B. bassiana, although our results showed significant differences between techniques. Leaf spraying was the most effective, with the highest percentage of colonization recorded 7 days after inoculation. We also evaluated (i) the effect on the mortality of T. absoluta by direct contact with conidia of B. bassiana, and (ii) the effect on tomato leaf consumption and mortality by indirect contact through ingestion of inoculated plant tissues with B. bassiana. Mortality bioassays showed that B. bassiana infected T. absoluta, either by direct contact or indirectly, via ingestion of inoculated tomato leaves. Direct contact showed a higher percentage of mortality and a lower median survival time (MST) than indirect contact. Significant differences in the mortality percentages of T. absoluta after exposure with B. bassiana were found among the treatments and the control. Our results suggest that the endophytic inoculation of B. bassiana in tomato crops provides the basis for further investigation, which should focus on the virulence of the endophytic B. bassiana against T. absoluta.
Źródło:
Journal of Plant Protection Research; 2017, 57, 4
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Pollen spectrum and risk of pollen allergy in Central Spain
Autorzy:
Perez-Badia, R
Rapp, A.
Morales, C.
Sardinero, S.
Galan, C.
Garcia-Mozo, H.
Powiązania:
https://bibliotekanauki.pl/articles/50546.pdf
Data publikacji:
2010
Wydawca:
Instytut Medycyny Wsi
Tematy:
aerobiology
atmospheric pollen
meteorology
pollen calendar
pollen allergy
allergy risk
pollinosis
Central Spain
Spain
Źródło:
Annals of Agricultural and Environmental Medicine; 2010, 17, 1; 139-151
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Welding Effects on the Mechanical Integrity of a Trip800 Steel: a Comparison of Laser Co2 and Gmaw Processes
Wpływ spawania na integralność mechanicznaą stali Trip800: porównanie spawania laserowego ze spawaniem elektrodą topliwą
Autorzy:
Perez-Medina, G. Y.
Lopez, H. F.
Reyes-Valdes, F. A.
Garza-Gomez, A.
Lopez-Ochoa, L. M.
Powiązania:
https://bibliotekanauki.pl/articles/351511.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
laser
GMAW
retained austenite
color metallography
spawanie elektrodą topliwą
austenit resztkowy
metalografia barwna
Opis:
In this work a strip of a transformation induced plasticity (TRIP) steel was welded using gas metal arc welding (GMAW) and Laser CO2 welding (LBW) processes and the resultant strength and ductility of the welded joints evaluated. It was found that LBW lead to relatively high hardness in the fusion zone, FZ where the resultant microstructure was predominantly martensite. The relative volume fractions of phases developed in the welded regions were quantitatively measured using color metallography combined with X-ray diffraction analyses. It was found that the heat affected zone, HAZ developed the maximum amount of martensite (up to 32%) in the steel welded using LBW besides a mixture of bainite, retained austenite and ferrite phases. In contrast, a relatively low percent of martensite (10.8%) was found in the HAZ when the GMAW process was implemented.
Pas ze stali typu TRIP poddano spawaniu elektrodą topliwą oraz spawaniu laserowemu i oceniono wytrzymałość i plastyczność uzyskanych połączeń spawanych. Stwierdzono, że spawanie laserowe prowadzi do uzyskania stosunkowo wysokiej twardości w strefie łączenia, gdzie powstała mikrostrukturę stanowi głównie martenzyt. Względne udziały objętościowe faz w spawanych obszarach zmierzono ilościowo za pomocą barwnej metalografii w połączeniu z dyfrakcyjną analizą rentgenowską. Stwierdzono, że w przypadku stali spawanej laserowo strefa wpływu ciepła zawiera najwięcej martenzytu (do 32%), a oprócz tego mieszanine bainitu, resztkowego austenitu i ferrytu. Natomiast w strefie wpływu ciepła uzyskanej podczas spawania elektrodą topliwą stwierdzono stosunkowo niską zawartość martenzytu (10,8%).
Źródło:
Archives of Metallurgy and Materials; 2014, 59, 4; 1427-1432
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Feeding habits and habitat of herbivorous mammals from the Early–Late Hemphillian (Miocene) of Costa Rica
Autorzy:
Perez-Crespo, V.A.
Laurito, C.A.
Arroyo-Cabrales, J.
Valerio, A.L.
Morales-Puente, P.
Cienfuegos-Alvarado, E.
Otero, F.J.
Powiązania:
https://bibliotekanauki.pl/articles/21193.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
Carbon and oxygen stable isotope values in the dental enamel of fossils were used to infer the diet and habitat of the extinct equids Calippus hondurensis, Dinohippus mexicanus, and Protohippus gidleyi, the gomphothere Gomphotherium hondurensis, and the llama Hemiauchenia vera of the Early–Late Hemphillian (Hh2) from San Gerardo de Limoncito, Puntarenas province, Costa Rica. The results suggest that these mammals fed mainly on C₃ plants and lived in clearings of rainforests. This contrasts with previous studies from North America that indicated that the same species lived in forest savannas and fed mainly on C₄ plants, but it is similar to the results obtained from the palynological record of the area, as well as with several vegetation models suggesting the presence of humid tropical forest during the Miocene in Central America.
Źródło:
Acta Palaeontologica Polonica; 2018, 63, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application for functionality and registration in the cloud of a microcontroller development board for IoT in AWS
Autorzy:
Pérez, Elizabeth
Araiza, Juan C.
Pozos, Dreysy
Bonilla, Edmundo
Hernández, José C.
Cortes, Jesús A.
Powiązania:
https://bibliotekanauki.pl/articles/1837785.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Promocji Wiedzy
Tematy:
AWS
IoT
MQTT
Opis:
The use of the Amazon Web Services cloud enables new functionalities that are not possible with traditional solutions: low latency, local data processing and storage, and direct connectivity to other cloud services. Reimagining the way IoT connectivity services are presented by combining AWS cloud technology with mobile connectivity offers rapid prototyping to help connect devices natively over Wi-Fi. For this, the MQTT communication protocol is used to interact with the IoT device and exchange data, which allows controlling the basic functions of a sensor node. The installation is realized through a software development kit (SDK), which allows the creation of an application for Android devices. This solution gives the option to integrate together, improving the connectivity of the IoT system. The results enable board logging and network configuration, and can also be used to control the IoT device. The embedded firmware provides the required security functions.
Źródło:
Applied Computer Science; 2021, 17, 2; 14-27
1895-3735
Pojawia się w:
Applied Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Potent Application of the Lyophilized Aqueous Leaf Extract of Euphorbia hirta (Tawa-Tawa) in the Development of a Naturally Flavored Ice Cream
Autorzy:
Ureta, Mark Jubille Niño M.
Perez, Imee Nicolle A.
Carmona, Vanessa Mae C.
Uretad, Romnick M.
Powiązania:
https://bibliotekanauki.pl/articles/1055273.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Antioxidant vitamins
Euphorbi hirta
Folkloric plant
Healthy ice cream
Indigenous medicinal plant
Phytochemicals
Opis:
Euphorbia hirta (Tawa-tawa), also known as “gatas-gatas”, is a hairy herb grown in open grasslands, roadsides and pathways. This indigenous plant is considered as one of the most popular folkloric treatment for dengue in the Philippines. When researched, Tawa-tawa was found to be able to promote cell production, and to prevent platelet destruction (Philippine Council for Health Research and Development, 2013). In this study, a new application of the plant was evaluated. This was as a natural supplement for ice cream production without the degradation of its essential compounds. Fresh leaves of E. hirta were oven dried and macerated to water for 48 hours. The obtained extracts were subjected to lyophilization to prevent potential degradation of plant’s essectial compounds. Ice cream formulation was added with the obtained powdered extract of E. hirta. Results revealed that the lyophilized extracts from E. hirta leaves contained flavonoids, alkaloids, phenols and saponins. Promising amounts of Vitamin B2 (5.02 mg/kg), Beta-carotene (9.8 mg/kg), Vitamin E (23.8 mg/kg) and Vitamin C (80.2 mg/kg) were also obtained. Meanwhile, the E. hirta supplemented ice cream was negative to Salmonella and a 16 CFU/g for Total Coliform Count was found. What is more, organoleptic testing for both taste and texture revealed excellent responses and very good aroma. The findings of the current study affirmed the feasibility of developing a naturally-based ice cream product supplemented with a medicinal plant like E. hirta. The results indicate that the developed ice cream is safer and healthier, hence could encourage everyone to enjoy the delights of eating ice cream without worry of gastronomic distress.
Źródło:
World News of Natural Sciences; 2018, 21; 118-129
2543-5426
Pojawia się w:
World News of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Obtaining a Rough Flux Front in Type-II Superconductors Using a Critical State Model
Autorzy:
Romero-Salazar, C.
Hernández-Flores, O.
Chabanenko, V.
Kuchuk, E.
Abaloszewa, I.
Nabialek, A.
Pérez-Rodríguez, F.
Powiązania:
https://bibliotekanauki.pl/articles/1398648.pdf
Data publikacji:
2016-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.20.-z
74.20.De
74.25.Ha
74.25.N-
74.25.Op
74.25.Sv
74.25.Wx
74.62.Dh
74.81.-g
Opis:
In this work we numerically modelled a periodic magnetic flux pattern which qualitatively reproduces the so-called sand avalanches scenario in type-II superconductors. To model these sand-pile patterns we consider a perturbation on the critical current which, as a first approximation, follows a periodic function which depends on the position.
Źródło:
Acta Physica Polonica A; 2016, 130, 2; 645-648
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Heavy moving average distances in sales forecasting
Autorzy:
Olazabal-Lugo, Maricruz
Espinoza-Audelo, Luis F.
León-Castro, Ernesto
Perez-Arellano, Luis A.
Blanco-Mesa, Fabio
Powiązania:
https://bibliotekanauki.pl/articles/27314242.pdf
Data publikacji:
2023
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
heavy moving average distance
OWA operator
distance measures
sales forecasting
Opis:
This paper presents a new aggregation operator tech‐ nique that uses the ordered weighted average (OWA), heavy aggregation operators, Hamming distance, and moving averages. This approach is called heavy ordered weighted moving average distance (HOWMAD). The main advantage of this operator is that it can use the characteristics of the HOWMA operator to under‐ or over‐ estimate the results according to the expectations and the knowledge of the future scenarios, analyze the his‐ torical data of the moving average, and compare the different alternatives with the ideal results of the dis‐ tance measures. Some of the main families and specific cases using generalized and quasi‐arithmetic means are presented, such as the generalized heavy moving aver‐ age distance and a generalized HOWMAD. This study develops an application of this operator in forecasting the sales growth rate for a commercial company. We find that it is possible to determine whether the company’s objectives can be achieved or must be reevaluated in response to the actual situation and future expectations of the enterprise.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2023, 17, 2; 18--27
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vascular structure of the earliest shark teeth
Autorzy:
Martínez-Pérez, C.
Martín-Lazaro, A.
Ferrón, H. G.
Kirstein, M.
Donoghue, P. C. J.
Botella, H.
Powiązania:
https://bibliotekanauki.pl/articles/139170.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Leonodus
Celtiberina
early chondrichthyans
Lower Devonian
synchrotron tomography
vascular system
ryby chrzęstnoszkieletowe
ryby chrzęstne
chrzęstniki
dolny dewon
tomografia
układ naczyniowy
Opis:
Here we use synchrotron tomography to characterise dental vasculature in the oldest known tooth-bearing sharks, Leonodus carlsi Mader, 1986 and Celtiberina maderi Wang, 1993. Three dimensional reconstruction of the vascular system and microstructure of both taxa revealed a complex and dense network of canals, including horizontal, ascending and secondary bifurcated canals, as well as histological features consistent with an osteodont histotype. However, L. carlsi and C. maderi also exhibit significant morphological differences, showing Leonodus a typical diplodont tooth morphology with a linguo-labially elongated base, that contrast with Celtiberina’s teeth that show a single conical cusp curved lingually with a week developed flat base mesio-distally extended, perhaps reflecting distant relationship. These data are compatible with a pre-Devonian diversification of the two main tooth types traditionally recognised in Palaeozoic sharks (i.e., “cladodont” vs “diplodont”). Finally, our data demonstrate that existing dental classification schemes based on styles of vascularisation are over-simplified, especially when Palaeozoic taxa are considered.
Źródło:
Acta Geologica Polonica; 2018, 68, 3; 457-465
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Validation of a flow cytometry-based assay for monitoring complement-dependent cytotoxicity of an anti-CD20 biosimilar candidate antibody
Autorzy:
Blanco-Santana, R.
Cedeno-Arias, M.
Garcia-Perez, Z.
Columbie-Gilbert, D.
Portillo-Vaquer, A.
Rengifo-Calzado, E.
Powiązania:
https://bibliotekanauki.pl/articles/80888.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
flow cytometry
validation
complement-dependent cytotoxicity
monoclonal antibody
CD20 antigen
biological activity
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2014, 95, 1
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The essential oil of the protected species: Thymus praecox ssp. penyalarensis
Autorzy:
Salas, J.B.
Tellez, T.R.
Pardo, F.M.V.
Perez-Alonso, M.J.
Capdevila, M.A.C.
Powiązania:
https://bibliotekanauki.pl/articles/57194.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
essential oil
protected species
Thymus praecox ssp.penyalarensis
endemism
threatened species
chemical composition
Lamiaceae
plant species
Opis:
The essential oil of a protected Spanish species, Thymus praecox ssp. penyalarensis, was firstly analyzed [Gas Chromatography-Mass Spectrometry (GC-MS)] from wild populations during the phenological stages of flowering and fruiting. In flowering, the yield was 1.2%, and the major components were identified as thymol (18.5%), p-cymene (14.6%), carvacrol (11.6%), and γ-terpinene (10.1%). In fruiting, the yield was 0.9% and the major components resulted to be p-cymene (19.0%), carvacrol (16.5%), and borneol (10.5%). An experimental cultivation of the taxa was made also in order to analyze its essential oil as well. The yield was 1.3%, and the main compounds were thymol (19.1%), p-cymene (17.0%), and γ-terpinene (12.3%). Finally, the composition of the essential oil of this plant is discussed in relation to chemotaxonomic and biogeographical aspects.
Źródło:
Acta Societatis Botanicorum Poloniae; 2012, 81, 1
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical and Physical Parametric Analysis of a SEN with Flow Conditioners in Slab Continuous Casting Mold
Autorzy:
Gonzalez-Trejo, J.
Real-Ramirez, C. A.
Miranda-Tello, R.
Rivera-Perez, F.
Cervantes-de-la-Torre, F.
Powiązania:
https://bibliotekanauki.pl/articles/351515.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
submerged entry nozzle
fluid-flow modifiers
continuous casting of steel
mold flow patterns
turbulence
Opis:
Some of the most recent technologies that improves the performance in continuous casting process has installed infrastructure outside the mold to modify the natural fluid flow pattern to obtain a quasi-steady condition and promote a uniform solidified shell of steel. The submerged entry nozzle distributes the liquid steel in the mold and can be used to obtain the flow symmetry condition with external geometry improvements. The fluid flow conditioners were located near the outlet ports of the nozzle. The aim of the modifiers is to impose a pseudo symmetric pattern in the upper zone of the mold by inhibiting the fluid exchange between the zones created by conditioners. This work evaluates the effect of the thickness and length of the fluid-flow modifiers on the overall performance of the submerged nozzle. These properties of the fluid-flow modifiers were normalized based on two of the geometric dimensions of the standard equipment. Numerical and physical simulations suggest that the flow modifier should be as thin as possible.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 2A; 927-946
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Conservation of the genetic diversity of local corn (Zea mays L.) in the Yucatan Peninsula, Mexico
Autorzy:
González-Valdivia, Noel A.
Cetzal-Ix, William
Basu, Saikat Kumar
Pérez-Ramírez, Isidra
Martínez-Puc, Jesús F.
Zandi, Peiman
Powiązania:
https://bibliotekanauki.pl/articles/2182157.pdf
Data publikacji:
2016-12-31
Wydawca:
Uniwersytet Pedagogiczny im. Komisji Edukacji Narodowej w Krakowie
Tematy:
Campeche
conservation
corn
cultivation
diversity genetic
Mexico
Yucatán
Opis:
The production of native corn at regional level is greatly limited by the seasonality of rainfall, availability of adequate lands, poor fertility status of the soil, high input costs and constraints of resources of the local corn growers and/or producers. The challenges of reduced cultivable area give very little opportunity for increasing production area in a sustainable manner; it is important to note that the soil recover their fertility status through crop rotation and prolonged rest period (> 25 years) known as sequential agroforestry system or "milpa". During 2015, corn collections were performed in the Yucatan Peninsula, Mexico that included five races from the Yucatan (in localities of Nohacal and Peto) and Campeche (Calakmul, Suc-Tuc, Sakabchen, I Chek) states. The races identified were: 1) Nal-Tel (gallito), 2) Dzit Bacal, 3) Xnu’uc Naal (Tuxpeño), 4) Palomero and, 5) Tabloncillo. The local varieties, Pix Cristo (Knees of Christ), Eh Hu (Purple maize) and Chac Chu’ub (Chac´s Blood or Red maize), are included within the Tuxpeño (Xnu´uk Naal) race. The land race of corn that is in imminent danger of extinction is Nal-Tel, characterized by its precocity and ability to escape periods of low rainfall; is important to rescue it for adoption to the practices of local and regional production. The adaptation of this race as a germplasm is important due to its resilience to climate change itself. Palomero, Tabloncillo, Pix Cristo, Chac Chu´ub and Eh Hu can thus be used in traditional food industry, to preserve the traditional knowledge and to provide opportunities for additional income for the local, rural communities. Yellow Palomero and Tabloncillo races are new records of germplasm for the region; and hence essential is exchanging their seeds among local producers and growers.
Źródło:
Annales Universitatis Paedagogicae Cracoviensis Studia Naturae; 2016, 1; 71-84
2543-8832
2545-0999
Pojawia się w:
Annales Universitatis Paedagogicae Cracoviensis Studia Naturae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modern building materials
Autorzy:
Sadowska, Beata
Jimenez, José Ramón
Fernández Rodriguez, José María
Moreno Pérez, Fátima
Roldán Cañas, José
Rivas-Sánchez, Yair A.
Powiązania:
https://bibliotekanauki.pl/chapters/31029469.pdf
Data publikacji:
2019
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
Building materials
environment
traditional material
industrialized materials
Opis:
Decisions taken both in the design process of buildings and their modernization should comply with basic requirements, such as: strength and stability, resistance to dampness and water, resistance to fire, heat insulation, sound insulation, durability, comforts and conveniences. Building materials should not have harmful effects on human health. In their production, factors that destroy the natural environment (e.g. freons that destroy the ozone layer in the atmosphere) should not be used. The aspects of utilization, safe storage and recycling possibilities are also important. Another criterion for choosing material solutions is their availability as well as local traditions. However, the deciding factor is usually the economic aspect (costs of materials, construction and assembly).
Źródło:
Buildings 2020+. Constructions, materials and installations; 53-105
9788365596703
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Changes in masa and tortillas obtained from maize irradiated and nixtamalized with nejayote
Autorzy:
Valderrama-Bravo, C.
Domínguez-Pacheco, F.A.
Hernandez-Aguilar, C.
Sanchez-Hernandez, G.
Perez-Reyes, C.
Contreras-Padilla, M.
Rojas-Gonzalez, T.
Oaxaca-Luna, A.
Powiązania:
https://bibliotekanauki.pl/articles/24252.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Źródło:
International Agrophysics; 2018, 32, 3
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Transcriptomic profiling of linolenic acid-responsive genes in ROS signalling from RNA-seq data in Arabidopsis
Autorzy:
Mata-Perez, C.
Sanchez-Calvo, B.
Begara-Morales, J.
Padilla, M.
Valderrama, R.
Luque, F.
Fernandez-Ocana, A.
Corpas, F.
Barroso, J.
Powiązania:
https://bibliotekanauki.pl/articles/80890.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
linoleic acid
polyunsaturated fatty acid
jasmonic acid
phytohormone
reactive oxygen species
hydrogen peroxide
gene expression
Arabidopsis thaliana
lipoxygenase
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Differential transcriptomic analysis by RNA-seq of GSNO-responsive genes between Arabidopsis roots and leaves
Autorzy:
Begara-Morales, J.
Sanchez-Calvo, B.
Luque, F.
Laterrier, M.
Valderrama, R.
Mata-Perez, C.
Padilla, M.
Carreras, A.
Corpas, F.
Barroso, J.
Powiązania:
https://bibliotekanauki.pl/articles/81065.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
transcriptome
RNA sequence
S-nitrosoglutathione
nitric oxide
stress condition
physiological condition
gene expression
root
leaf
Arabidopsis
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dual regulation of cytosolic ascorbate peroxide (APX) by tyrosine nitration and S-nitrosylation
Autorzy:
Begara-Morales, J.
Sanchez-Calvo, B.
Chaki, M.
Valderrama, R.
Mata-Perez, C.
Lopez-Jaramillo, J.
Carreras, A.
Padilla, M.
Corpas, F.
Barroso, J.
Powiązania:
https://bibliotekanauki.pl/articles/80378.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
post-translational modification
nitric oxide
target protein
ascorbate peroxidase
tyrosine nitration
S-nitrosylation
salinity stress
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
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