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Wyszukujesz frazę "Silva, R." wg kryterium: Autor


Tytuł:
Dynamic Properties of Concrete Composite Panels under Eccentric Compression Loading Tests
Autorzy:
Magalhaes, M.
Silva, R. M.
Powiązania:
https://bibliotekanauki.pl/articles/176872.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
dynamic analysis
composite panels
in-plane loading
pre-stressed panels
Opis:
The main aim of this paper is to examine the variability of some dynamic properties of concrete composite panels to in-plane eccentric compression loads via static and dynamic impact testing. First, experimental tests were performed in order to obtain the dynamic and static properties of concrete composite panels. In-plane eccentric loads were statically applied to a couple of panels in ten uniform steps. For each step, dynamic impact testing was performed and the modal damping, peak amplitude and natural frequencies obtained. Second, a ‘hybrid’ model, based on the concepts of modal analysis and the Finite Element Method, was developed in order to obtain the natural frequencies and corresponding normal modes of the composite panels within the frequency range 0–200 Hz. For this model, an initial warp of the panel middle surface was incorporated into the formulation in order to represent the applied flexural moment provoked by the eccentric in-plane loads. The accuracy of the ‘hybrid’ model was verified by comparison with the experimental results. Third, comparison is made between predictions (using on the ‘hybrid’ model) and experimental results.
Źródło:
Archives of Acoustics; 2015, 40, 2; 169-181
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hierarchical Multiobjective Routing Model in MPLS Networks with Two Service Classes - A Comparison Case Study
Autorzy:
Girao-Silva, R.
Craveirinha, J.
Clímaco, J.
Powiązania:
https://bibliotekanauki.pl/articles/309205.pdf
Data publikacji:
2012
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
multiobjective optimization
routing models
simulation
telecommunication networks
Opis:
A two-level hierarchical multicriteria routing model for multiprotocol label switching networks with two service classes (QoS, i.e., with quality of service requirements, and best effort services) and alternative routing is reviewed in this paper. A heuristic resolution approach, where nondominated solutions are obtained throughout the heuristic run and kept in an archive for further analysis is also reviewed. In this paper, an extensive analysis of the application of this procedure to two reference test networks for various traffic matrices is presented. Also a comparison of the results of our method with a lexicographic optimization approach based on a multicommodity flow formulation using virtual networks is carried out. Finally, results of a stochastic discrete event simulation model developed for these networks will be shown to illustrate the effectiveness of the resolution approach and to assess the inaccuracies of the analytic results.
Źródło:
Journal of Telecommunications and Information Technology; 2012, 2; 29-42
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hierarchical Multiobjective Routing in MPLS Networks with Two Service Classes - A Meta-Heuristic Solution
Autorzy:
Girao-Silva, R.
Craveirinha, J.
Clímaco, J.
Powiązania:
https://bibliotekanauki.pl/articles/308908.pdf
Data publikacji:
2009
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
multiobjective optimization
MPLS-Internet
routing models
simulated annealing
tabu search
Opis:
The paper begins by reviewing a two-level hierarchical multicriteria routing model for MPLS networks with two service classes (QoS and BE services) and alternative routing, as well as the foundations of a heuristic resolution approach, previously proposed by the authors. Afterwards a new approach, of meta-heuristic nature, based on the introduction of simulated annealing and tabu search techniques, in the structure of the dedicated heuristic, is described. The application of the developed procedures to a benchmarking case study will show that, in certain initial conditions, this approach provides improvements in the final results especially in more "difficult" situations detected through sensitivity analysis.
Źródło:
Journal of Telecommunications and Information Technology; 2009, 3; 20-37
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spatial analysis of vegetal cover and sediment yield in Tapacura river catchment based on remote sensing and GIS
Analiza przestrzenna ilosci sedymentu oraz pokrywy roslinnej w zlewni rzeki Tapacura okreslona na podstawie zdalnych obserwacji oraz analizy GIS
Autorzy:
Silva, R M
Santos, C.A.G.
Gico Lima Montenegro, S.M.
Silva, L.P.
Powiązania:
https://bibliotekanauki.pl/articles/81843.pdf
Data publikacji:
2010
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
spatial analysis
vegetation cover
sediment yield
Tapacura River
catchment
remote sensing
GIS analysis
Opis:
Mapping and assessment of erosion risk is an important tool for planning of natural resources management, allowing researchers to propose modifi cation in land-use properly and implement more sustainable management strategies in the long-term. The Tapacurá river catchment, located in Pernambuco State, Northeastern Brazil, is one of the planning units for management of water resources of Recife Metropilitan Region (RMR), and it is divided into 12 sub-basins. The objective of this study is to evaluate the spatial variability of vegetal cover and sediment yield in this basin through remote sensing and GIS techniques. Maps of the erosivity (R), erodibility (K), topographic (LS), cover-management (C) and support practice (P) factors were derived from the digital elevation model (DEM), climate database, and soil and NDVI maps, taking into account information available in the literature. In order to validate the simulation process, Sediment Delivery Ratio (SDR) was estimated. The obtained NDVI map showed vegetation loss during the analyzed period, indicating a distinct contrast between loss and gains of vegetation index. The vegetation and sediment yield mapping showed to be a useful tool for environmental monitoring and management, which can provide satisfactory results when jointly used. The results suggest a mean SDR around 0.9 and estimate the sediment yield as 23.98 ton/ha/month.
Analiza przestrzenna ilości sedymentu oraz pokrywy roślinnej w zlewni rzeki Tapacura określona na podstawie zdalnych obserwacji oraz analizy GIS. Artykuł przedstawia sposób wykorzystania zebranych w terenie danych dotyczących pokrywy roślinnej oraz ilości sedymentu określonego za pomocą zdalnych obserwacji oraz analizy GIS w celu monitorowania środowiska i zarządzania zlewniami. W pracy wykorzystano metodę USLE-SDR, a także cyfrowy model terenu. Badania prowadzono w zlewni rzeki Tapacura w północno-wschodniej Brazylii. Wyniki sugerują przyjęcie wartości parametru SDR = 0,9, a oszacowana wielkość transportu rumowiska wynosi 23,98 t/ha/miesiąc.
Źródło:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation; 2010, 42, 1; 5-16
0208-5771
Pojawia się w:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fatigue design and prevention in movable scaffolding systems
Projektowanie ruchomych systemów rusztowań z uwzględnieniem obciążęń zmęczeniowych
Autorzy:
Coelho, H.
Torres, A.
Pacheco, P.
Moreira, C.
Silva, R.
Soares, J. M.
Pinto, D.
Powiązania:
https://bibliotekanauki.pl/articles/396185.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
mosty
Movable Scaffolding System
MSS
system ruchomych rusztowań
obciążenia zmęczeniowe
bridge construction
fatigue
Opis:
The Movable Scaffolding System (MSS) is a heavy construction equipment used for casting situ of concrete bridge decks. In the past decades, MSSs have become increasingly complex and industrialized, enlarging its span ranges, incorporating auxiliary elevation machinery and increasing productivity. The tendency nowadays is for strong reutilization and the notion of MSS as a disposable or temporary structure is somehow reductive. The main structure of MSSs may be potentially exposed to fatigue, usually characterized by low number of cycles with significant stress amplitude. Fatigue may be prevented through adequate design; judicious selection of materials; demanding quality control and implementation of robust inspection and maintenance plans.
System ruchomych rusztowań – Movable Scaffolding System (MSS) to ciężki konstrukcja budowlana wspomagająca wykonanie betonowych mostów. W ostatnich dekadach MSS stały się coraz bardziej skomplikowane i uniwersalne, stanowią element nośny dla wielu urządzeń zarówno podczas wykonywania mostu jak i podczas eksploatacji. Główna struktura systemów MSS może być narażona na efekt zmęczenia, obiążenia zwykle charakteryzują się niską liczbą cykli o znacznej amplitudzie naprężeń. Zmęczeniu można zapobiec poprzez odpowiedni projekt i rozsądny dobór materiałów. Jest to konstrukcja wymagająca ścisłej kontroli jakości i wdrożenia solidnych planów inspekcji i konserwacji.
Źródło:
Civil and Environmental Engineering Reports; 2017, No. 25(2); 77-88
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Finding Playing Styles of Badminton Players Using Firefly Algorithm Based Clustering Algorithms
Autorzy:
Ilankoon, I.M.T.P.K.
Samarasinghe, U.S.
Ariyaratne, M.K.A.
Silva, R. M.
Powiązania:
https://bibliotekanauki.pl/articles/27312858.pdf
Data publikacji:
2023
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
firefly algorithm
clustering
intra- and inter-cluster distance
badminton
Opis:
Cluster analysis can be defined as applying clustering algorithms with the goalof finding any hidden patterns or groupings in a data set. Different clusteringmethods may provide different solutions for the same data set. Traditionalclustering algorithms are popular, but handling big data sets is beyond theabilities of such methods. We propose three big data clustering methods basedon the firefly algorithm (FA). Three different fitness functions were definedon FA using inter-cluster distance, intra-cluster distance, silhouette value, andthe Calinski-Harabasz index. The algorithms find the most appropriate clustercenters for a given data set. The algorithms were tested with nine popularsynthetic data sets and one medical data set and are later applied on two bad-minton data sets with the intention of identifying the different playing stylesof players based on their physical characteristics. The results specify that thefirefly algorithm could generate better clustering results with high accuracy.The algorithms cluster the players to find the most suitable playing strategyfor a given player where expert knowledge is needed in labeling the clusters.Comparisons with a PSO-based clustering algorithm (APSO) and traditional al-gorithms point out that the proposed firefly variants work in a similar fashion asthe APSO method, and they surpass the performance of traditional algorithms.
Źródło:
Computer Science; 2023, 24 (3); 427--450
1508-2806
2300-7036
Pojawia się w:
Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Premises of dairy systems development on an example of Polish and Portuguese conditions
Przesłanki rozwoju systemu mleczarskiego na przykładzie warunków produkcji mleka w Polsce i Portugalii
Autorzy:
Fernandes, F.
Pereira, P.
Silva, V.R.
Borowski, P.
Gaworski, M.
Powiązania:
https://bibliotekanauki.pl/articles/56207.pdf
Data publikacji:
2014
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
dairy system
production development
dairy production
Polska
Portugal
country
farm
farm condition
European Union
Źródło:
Annals of Warsaw University of Life Sciences - SGGW. Agriculture; 2014, 64 Agric.Forest Eng.
0208-5712
Pojawia się w:
Annals of Warsaw University of Life Sciences - SGGW. Agriculture
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Attachment of 2,2-bipyridine onto a silica gel for application as a sequestering agent for copper, cadmium and lead ions from an aqueous medium
Autorzy:
Souza, E. J.
Cristante, V. M.
Padilha, P. M.
Jorge, S. M. A.
Martines, M. A. U.
Silva, R. I. V.
Carmo, D. R.
Castro, G. R.
Powiązania:
https://bibliotekanauki.pl/articles/779827.pdf
Data publikacji:
2011
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
2,2-bipirydyna
żel krzemionkowy
adsorpcja
jony metali
2,2'-bipyridine
silica gel
adsorption
metal ions
Opis:
A method was developed to attach 2,2-bipyridine (BP) onto a silica gel surface by a two-step reaction. The fi rst step consisted of a reaction between the matrix and a silylating agent, 3-chloropropyltrimethoxysilane. In the second step of the reaction, a ligand molecule was attached onto Si-CPTS, yielding the product Si-BP. The modified material contained 0.431±0.01 mmol of 2,2-bipyridine per gram of modified silica, as confirmed by FT-IR spectra of the proposed structure. The surface modification was characterized by the BET technique, which revealed a decrease in the surface area from 614 to 450 m2 g-1. The series of adsorption isotherms for the metal ions were adjusted to fit a modified Langmuir equation. The maximum number of moles of copper, cadmium and lead ions adsorbed was 0.64, 0.53, and 0.54 mmol g-1, respectively. The surface saturation was calculated as ¢ fraction and the values obtained, Cu(II) =1.160, Cd(II) = 1.044 and Pb(II) = 0.997, suggest a type 1:1 metal-ligand complex.
Źródło:
Polish Journal of Chemical Technology; 2011, 13, 4; 28-33
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanical Spectroscopy of MgB2 Containing SiC
Spektroskopia mechaniczna MgB2 zawierającego SiC
Autorzy:
Silva, M. R.
Silva, L. B. S.
Rodriques Jr., D.
Grandini, C. R.
Powiązania:
https://bibliotekanauki.pl/articles/355880.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
mechanical spectroscopy
internal friction
anelasticity
MgB2
SiC
spektroskopia mechaniczna
tarcie wewnętrzne
właściwości anelastyczne
Opis:
The compound magnesium diboride (MgB2) has been well-known since the 1950s; however, its superconducting properties were unknown. Intrinsic characteristics of MgB2 make this material a promising candidate for technological applications, although the low value of the irreversibility field and the decrease in critical current density with the increase in the magnetic field considerably reduce its utility. The present work aimed to study the effect of carbon-based doping on anelastic properties of MgB2 as measured by mechanical spectroscopy. The samples were prepared by using the powder-intube method. The samples were made with 5, 7.5, and 10 wt.% of silicon carbide (SiC). The results reveal complex mechanical loss spectra caused by the interaction between point defects and surface defects in the crystalline lattice of MgB2.
Dwuborek związek magnezu (MgBV) jest znany od 1950 roku; jednak jego właściwości nadprzewodzące były nieznane. Swoiste cechy MgB2 czynią ten materiał obiecującym kandydatem do zastosowań technicznych, jednak niskie wartości nieodwracalnego pola i zmniejszenie krytycznej gęstości prądu ze wzrostem pola magnetycznego znacznie zmniejszają jego użyteczność. Celem pracy było zbadanie wpływu domieszkowania związkiem węgla na anelastyczne właściwości MgB2 mierzone metodą spektroskopii mechanicznej. Próbki zostały przygotowane za pomocą metody powder-in-tube (PIT). Wytworzono próbki o zawartości 5, 7.5 i 10 % wag. węglika krzemu (SiC). Wyniki pokazują złożone widma strat mechanicznych powodowanych przez wzajemne oddziaływanie pomiędzy defektami punktowymi i defektami powierzchniowymi w sieci krystalicznej MgB2.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 4; 3083-3086
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the effects of recycling on process control
Autorzy:
Silva, Cássio R.A.
Panuci, Victor C.
Coutinho, Monica R.
Conceição, Wagner A.S.
Andrade, Cid M.G.
Powiązania:
https://bibliotekanauki.pl/articles/27315644.pdf
Data publikacji:
2023
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
level control
control structure
decoupled tanks
cycle
Arduino
Opis:
The union of different devices in order to obtain a specific response for a process is commonly called a control system. For a control system, it is necessary to have one or more controllers. Among the most used in the industrial sector are the PID and PI controllers. Next to these controllers is the control software. Scilab is a good example of control software. It is characterized as free code software, with no cost for its acquisition, in addition to having a large computational power and integrated tools, such as Xcos, intended for modeling and simulation. For the union with Scilab, there is Arduino. Such a mixture can be used, for example, to control liquid levels in tanks. In this context, the present work aims to study the tank-level control system based on PID and PI controllers through the union between Scilab and Arduino. Phenomenological models were developed based on closed-loop control (feedback control system) of the process with two tanks not coupled with recycle. Furthermore, for comparison purposes, two approaches were used for each process: one considering the saturation of the manipulated variable and the other without the presence of such saturation. At first, there was a need to implement an anti-windup system. For tuning the controller parameters, the ISE method was used, executed through a programming code developed in Scilab. The parameters found for the two systems were tested on a made-up experimental bench. Therefore, using the block diagrams and the method here called “ISE method”, satisfactory values were obtained for the control parameters. These were ratified in the tests carried out in the experimental module. Level control was achieved with greater prominence for the PI controller since there is one less parameter to be tuned and processed by the system. This controller provided results close to the PID controller for cycles up to 50%. In general, the PI controller showed maximum response deviations smaller than the PID, such as deviations of 1.55 cm and 2.40 cm, respectively, for the case with 75% recycle. It was also clear the influence of the saturation of the manipulated variable on the system response, but not on the tuning of the controller parameterseters.
Źródło:
Polish Journal of Chemical Technology; 2023, 25, 2; 43--55
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Combined Analyses of Ion Beam Synthesized Layers in Porous Silicon
Autorzy:
Ramos, A. R.
Pászti, F.
Horváth, Z. E.
Vázsonyi, É.
Conde, O.
da Silva, M. F.
da Silva, M. R.
Soares, J. C.
Powiązania:
https://bibliotekanauki.pl/articles/2028988.pdf
Data publikacji:
2001-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.18.Bn
61.43.Gt
68.55.Ln
Opis:
High dose ion implantation was used to form polycrystalline silicide films on porous silicon with different native concentrations of light impurities (C and O). Porous silicon layers severalμm thick were implanted with 170 keV Cr$\text{}^{+}$ ions to fluences of 3×10$\text{}^{17}$ ions/cm$\text{}^{2}$ both at room temperature and 450ºC. Similar samples were implanted with 100 keV Co$\text{}^{+}$ ions to fluences of 2×10$\text{}^{17}$ ions/cm$\text{}^{2}$ at room temperature, 350ºC, and 450ºC. The formed silicide compounds were studied by Rutherford backscattering spectrometry, elastic recoil detection, glancing incidence X-ray diffraction, and four point-probe sheet resistance measurements. Selected Co implanted samples were analysed by cross-section transmission electron microscopy. Results show that the light impurities were partially expelled from the forming silicide layer. Combining cross-section transmission electron microscopy with ion beam methods it was possible to show that, in the implanted region, the porous structure collapses and densifies during implantation, but the underlying porous silicon remains intact. The layer structure, as well as the quality and type of the formed silicide, were found to depend on the original impurity level, implantation temperature, and annealing.
Źródło:
Acta Physica Polonica A; 2001, 100, 5; 773-780
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First record of mites associated with lima bean (Phaseolus lunatus L.)
Autorzy:
Neto, A.V.G.
Silva, P.R.R.
Silva, J.D.C.
Dos Santos, M.F.
Da Silva Melo, J.W.
De Franca, S.M.
Powiązania:
https://bibliotekanauki.pl/articles/2084632.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Tetranychidae
pest mites
legumes
Opis:
Pest mites of the family Tetranychidae are commonly reported in several legumes. However, reports of their occurrence in lima beans are insipient, especially in Brazil. The objective of this research was to record the occurrence of mites in lima bean plants and to describe their damage in this Fabaceae. Tetranychus neocaledonicus André and Mononychellus planki McGregor were found in lima bean plants, Phaseolus lunatus (Fabaceae or Leguminosae). The lima bean plants, when infested by these mites, initially exhibit small whitish spots in the leaflets, which with increasing population density rapidly evolve into chlorotic patches, followed by silvering, and may dry out and fall due to their overfeeding. The extent of the damage caused to lima bean plants and the adaptability of the mite to warm and dry conditions indicate that T. neocaledonicus has greater potential as a lima bean pest than M. planki in northeastern Brazil. This is the first record of these mites associated with P. lunatus.
Źródło:
Journal of Plant Protection Research; 2019, 59, 3; 418-422
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Selectivity of diphenyl-ether herbicide with postemergence applications in chickpea
Autorzy:
Silva, L.G.B.
Da Silva Araujo, L.
Goncalves, D.J.
Souza Valente, M.
Da Silva, A.R.
Nascimento, W.M.
Ribeiro da Cunha, P.C.
Powiązania:
https://bibliotekanauki.pl/articles/2084719.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cicer arietinum
diphenyl-ether herbicides
weeds
Opis:
There are few reports in literature about the selectivity of postemergence application of herbicides for the control of eudicotyledon weeds (broadleaf) in chickpea. For this reason, the aim of this study was to investigate the selectivity of diphenyl-ether herbicides in chickpea influenced by the herbicides and application rates. A field experiment was conducted from February to June 2017 in Urutaí, state of Goiás, Brazil. Cultivar BRS Aleppo was used in the experiment. The experiment was set up in a randomized block design with 2 × 3 + 1 factorial arrangement and three replications. The first factor was herbicides (fomesafen and lactofen) with the second factor being herbicide rate (50, 75, and 100% of referenced rate) plus an untreated check as a comparison. The applied rates of herbicides were 250 and 180 g ⋅ ha–1 of fomesafen and lactofen, respectively. The selectivity of herbicides was evaluated according to agronomic characteristics (plant population, height, dry matter, number of pods per plant and 100-grain weight) and yields. Both herbicides, regardless of dosage, were selective in chickpea cultivation, even exhibiting leaf necrosis symptoms with visible injuries below 20% with no effect on yield.
Źródło:
Journal of Plant Protection Research; 2019, 59, 3; 350-354
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Noise Exposure Levels of Priests and Worshippers in Protestant Churches
Autorzy:
Silva, L. F.
Cabral, R.
Powiązania:
https://bibliotekanauki.pl/articles/90659.pdf
Data publikacji:
2011
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
noise
exposure
churches
worship
Opis:
Context. Worship in Protestant churches in Brazil is very noisy. Thus, this practice may pose a hearing risk. Aims. To evaluate the priests’ and worshippersʼ noise exposure during worship. Settings and design. The analysis was carried out in 5 churches located in the city of São José dos Campos, Brazil. Methods and material. To estimate the worshippers’ noise exposure, an author of this study was also submitted to dosimetry. The methodology was based on Fundacentro’s Occupational Hygiene Standard No. NHO-01 (2001). Weekly noise exposure was estimated according to the priest’s information about the number of services in the period. Results. The priest’s noise exposure was over the recommended limits. The normalized exposure level varied between 95.4 to 99.5 dB(A). In 2 of the churches, the noise exposure registered, with values of 85.3 and 86.5 dB(A), may also pose risk to the worshippers. Conclusions. Worship in the churches generated sound pressure levels that imply health risk, especially to priests, so hearing conservation programs with adequate acoustical sanitation measures must be implemented there.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2011, 17, 1; 79-86
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The pustulated temnospondyl revisited - a plagiosternine plagiosaurid from the Lower Triassic of Brasil
Autorzy:
Dias-Da-Silva, S
Milner, A.R.
Powiązania:
https://bibliotekanauki.pl/articles/23465.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
temnospondyl
plagiosternine plagiosaurid
Lower Triassic
Triassic
paleontology
Brazil
plagiosaurid
systematics
morphology
Opis:
A recent contribution published in this journal (Dias−daSilva and Ilha 2009) reported a dermal skull fragment indicating the presence of a putative plagiosauroid temnospondyl in the Lower Triassic Sanga do Cabral Formation of the Paraná Basin, Southern Brazil. The taxonomic assignation of this specimen was necessarily tentative as it was based on circumstantial evidence, specifically the presence of a dense pustular ornamentation over four partial dermal skull bones, consideration of the described taxa known to bear such ornamentation, and the stratigraphic and paleobiogeographic range of such taxa. Therefore, Diasda−Silva and Ilha (2009) could not be totally certain about the plagiosauroid affinities of the new specimen and ascribed it to ?Plagiosauridae. It was particularly difficult to make a precise osteological identification of the specimen and six alternative osteological interpretations were made in comparison to both Gerrothorax and Peltobatrachus (see Dias−da−Silva and Ilha 2009: fig. 2). In spite of the poor taxonomic resolution, the new specimen raised interesting questions regarding the presence of plagiosauroid stereospondyls in western Gondwana, as well as their evolutionary patterns, biostratigraphic and paleobiogeographic implications. After Dias−da−Silva and Ilha's (2009) contribution was published, new data from Damiani et al. (2009) raised the possibility of narrowing down the taxonomic identity of the plagiosauroid from Brazil. Accordingly, this brief report provides a more precise taxonomic assignation for this material.
Źródło:
Acta Palaeontologica Polonica; 2010, 55, 3; 561-563
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effect of a Physical Activity Program on Decreasing Physical Disability Indicated by Musculoskeletal Pain and Related Symptoms Among Workers: A Pilot Study
Autorzy:
Moreira-Silva, I.
Santos, R.
Abreu, S.
Mota, J.
Powiązania:
https://bibliotekanauki.pl/articles/90298.pdf
Data publikacji:
2014
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
physical activity
musculoskeletal pain
workers
intervention study
choroby narządów ruchu
pracownik
aktywność psycho-ruchowa
aktywność fizyczna
program aktywności fizycznej
Opis:
The aim of this study was to verify the effect of a physical activity (PA) program on musculoskeletal pain and related symptoms in different body regions among workers. Methods. The intervention study lasted 6 months. The training sessions were given during work time. The intervention group (TOI) (n = 39) participated in 10–15 min of physical exercise training 3 times a week and focused on stretching exercises and general strength. The reference group (TOR) (n = 31) were asked to continue their daily activities. Musculoskeletal pain was assessed with the standardized Nordic questionnaires for analyzing musculoskeletal symptoms. Evaluations were performed at baseline and at the end of the intervention. Results. After the intervention, the TOI obtained some significant results regarding a decrease in the intensity of pain in some of the body regions evaluated, such as elbow (p = .03) and dorsal region (p = .015). In comparing the TOR and TOI after the 6 months of the PA program, we can verify that in the elbow and in the thigh/hip regions, the pain intensity decreased significantly; additionally, there is some evidence to suggest statistically significant results in the neck region (p = .063). Conclusion. Our intervention seems to have reduced musculoskeletal pain and related symptoms in factory workers.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2014, 20, 1; 55-64
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of position of fruits in a tree and number of fruits per panicle on growth and quality of citrus
Autorzy:
Sakhidin, -
Teixeira de Silva, J.A.
Suparto, S.R.
Powiązania:
https://bibliotekanauki.pl/articles/1076701.pdf
Data publikacji:
2018
Wydawca:
Instytut Ogrodnictwa
Tematy:
citrus
citrus fruit
citrus orchard
central Java
Indonesia
fruit diameter
fruit weight
fruit pulp
sugar content
vitamin C
Opis:
This research aimed to study the effect of the position of fruits in a tree (inner or outer) and the number of fruits per panicle (one, two or three) on the growth and quality of citrus ‘Pontianak’. The study was conducted in a citrus orchard in Central Java, Indonesia for two seasons, 2014/2015 and 2015/2016. The results indicated that position of fruits on the tree did not influence weight and diameter of fruits, weight of fruit pulp, and contents of sugars and total acids. Increasing the number of fruits per panicle decreased the weight and diameter of fruits and the weight of pulp but increased the contents of vitamin C and total acids.
Źródło:
Journal of Horticultural Research; 2018, 26, 1
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Foliar treatment with proline and tyrosine affect the growth and yield of beetroot and some pigments in beetroot leaves
Autorzy:
El-Sherbeny, M.R.
Teixeira da Silva, J.A.
Powiązania:
https://bibliotekanauki.pl/articles/2059.pdf
Data publikacji:
2013
Wydawca:
Instytut Ogrodnictwa
Tematy:
Beta vulgaris
red beet
pigment content
chlorophyll
carotenoid
proline
tyrosine
carbohydrate content
foliar treatment
vegetative growth
yield
Źródło:
Journal of Horticultural Research; 2013, 21, 2
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of meteorological parameters in hourly patterns of grass [Poaceae] pollen concentrations
Autorzy:
Munoz, Rodriguez A F
Silva Palacios, I.
Tormo Molina, R.
Powiązania:
https://bibliotekanauki.pl/articles/50296.pdf
Data publikacji:
2010
Wydawca:
Instytut Medycyny Wsi
Tematy:
Poaceae
grass
pollen
pollen concentration
meteorological parameter
pollination
pollen allergy
hourly pattern
Źródło:
Annals of Agricultural and Environmental Medicine; 2010, 17, 1; 87-100
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Loads on walls and inserts in a mass-flow silos
Autorzy:
Ding, S.
Wójcik, M.
Jecmenica, M.
Silva de, S. R.
Powiązania:
https://bibliotekanauki.pl/articles/1955779.pdf
Data publikacji:
2003
Wydawca:
Politechnika Gdańska
Tematy:
silo flow/loads
insert
Lagrangian-Eulerian
adaptive
fillet
Opis:
A finite element analysis has been carried out to investigate flow patterns and loads on silos either with a ralatively steep hopper, or with a shallow hopper but in the presence of an insert. A Lagrangian-Eulerian approach was first adopted to simulate the material flow pattern, with the precondition that mass flow was obtained. It was then attempted to predict the loads exerted by granular materials on the walls of such silos. The load on the insert was also simulated. Techniques such as the adoption of adaptive meshes and filleting along sharp corners were applied in the analysis to overcome the difficulties usually encountered with large deformations in the FEM and the mathematic singularity presented by the abruptness of geometry. Filleting proved to be necessary to bring down the pressure peak at the transition level. The insert took over a significant part of the loads. Comparison with the classic theories have confirmed that the loads predicted on the wall agree quite well with the theoretical results in the silo's cylinder section, but that differences exist in the hopper section; the difference is greater when the hopper is shallower. It has also shown the limitations of predicting flow patterns of granular materials with the traditional elastic-plastic model; a more advanced model is needed.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2003, 7, 4; 525-538
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The analysis of environmental and human impacts of using Strong Alkaline Water for cooling during machining
Autorzy:
Da Silva, P.
Tanabe, I.
Junior, D. C. R.
Takahashi, S.
Powiązania:
https://bibliotekanauki.pl/articles/99481.pdf
Data publikacji:
2018
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
eco-friendly
strong alkaline water
emission
cooling
Opis:
An eco-friendly manufacturing approach is important for the environment. Enhancing machining performances is not only required to improve product’s quality, time saving, and reduces costs; it is also contributed to the environmental protection efforts. Cooling is important aspect for obtaining this purpose. Therefore the benefits of Strong Alkaline Water (SAW) cooling method was assessed and compared with conventional wet cutting method. An experiment was performed at Nagaoka University of Technology machining centre. Three machine tools including a milling machine, a drilling machine and a turning machine were used. The study shows that using SAW for cooling is far more efficient than conventional cooling method. It reduces annual global warming potential by 72.95%, acidification potential 98.18%, ozone depletion potential 99.6%, smog formation potential 85.71% and human toxicity potential 42.86% compare with conventional method. The study concludes that besides inhibiting corrosion, prolonging tool life, improving surface roughness of final cutting and reducing energy usage, strong alkaline water cooling is an environmentally friendly approach and has positive impact on human health.
Źródło:
Journal of Machine Engineering; 2018, 18, 1; 45-60
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vortex Motion and Quasiparticle Resistivity in Superconductors at Microwave Frequencies
Autorzy:
Sarti, S.
Amabile, C.
Fastampa, R.
Giura, M.
Silva, E.
Pompeo, N.
Powiązania:
https://bibliotekanauki.pl/articles/2047225.pdf
Data publikacji:
2007-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.Nf
74.20.De
74.60.Ge
74.70.Ad
74.72.-h
Opis:
At nonzero frequencies both the normal and superfluid fractions, as well as moving vortices, contribute to the electrical transport, resulting in intricate expressions for the resistivity. We present an extended study of microwave resistivity data measured on YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$, SmBa$\text{}_{2}$ Cu$\text{}_{3}$O$\text{}_{7-δ}$, and MgB$\text{}_{2}$ by means of a broad-band technique between 2 and 20 GHz and of a resonant system at 50 GHz. We discuss the main experimental fingerprints that allow one to identify the relevance of the different contributions from the measured microwave response as a function of frequency, temperature, and magnetic field. We show that the field-dependent superfluid/quasiparticles dynamics cannot be in general neglected with respect to the vortex motion, albeit its relative importance is different in different materials: in high temperature superconductors vortex motion prevails at high fields, but at low fields a significant superfluid/quasiparticle contribution exists (ascribed to the presence of lines of nodes). In MgB$\text{}_{2}$ the two contributions are comparable even at high fields. In this general frame, we derive from the measurements vortex and superfluid parameters in agreement with theoretical predictions and independent measurements.
Źródło:
Acta Physica Polonica A; 2007, 111, 1; 87-93
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Linear-wavelet networks
Autorzy:
Galvao, R. K. H.
Becerra, V. M.
Calado, J. M. F.
Silva, P. M.
Powiązania:
https://bibliotekanauki.pl/articles/907399.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
sieć falkowa
model nieliniowy
analiza regresji
identyfikacja systemu
wavelet networks
nonlinear models
regression analysis
system identification
Opis:
This paper proposes a nonlinear regression structure comprising a wavelet network and a linear term. The introduction of the linear term is aimed at providing a more parsimonious interpolation in high-dimensional spaces when the modelling samples are sparse. A constructive procedure for building such structures, termed linear-wavelet networks, is described. For illustration, the proposed procedure is employed in the framework of dynamic system identification. In an example involving a simulated fermentation process, it is shown that a linear-wavelet network yields a smaller approximation error when compared with a wavelet network with the same number of regressors. The proposed technique is also applied to the identification of a pressure plant from experimental data. In this case, the results show that the introduction of wavelets considerably improves the prediction ability of a linear model. Standard errors on the estimated model coefficients are also calculated to assess the numerical conditioning of the identification process.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2004, 14, 2; 221-232
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal assisted switching magnetic tunnel junctions as FPGA memory elements
Autorzy:
Silva, V.
Fernandes, J. R.
Oliveira, L. B.
Neto, H. C.
Ferreira, R.
Freitas, S.
Freitas, P. P.
Powiązania:
https://bibliotekanauki.pl/articles/397855.pdf
Data publikacji:
2010
Wydawca:
Politechnika Łódzka. Wydział Mikroelektroniki i Informatyki
Tematy:
MRAM (oporność magnetyczna pamięci o dostępie swobodnym)
MTJ (magnetyczny tunel połączeń)
pisanie projektów (programów)
FIMS (pole indukowane magnetycznym przełącznikiem)
MRAM (magnetoresistive random access memory)
MTJ (magnetic tunnel junction)
writing schemes
FIMS (field induced magnetic switching)
TAS (thermal assisted switching)
STT
Opis:
This paper presents our research and development work on new circuits and topologies based on Magnetic RAM for use as configuration memory elements of reconfigurable arrays. MRAM provides non volatility with cell areas and with access speeds comparable to those of SRAM and with lower process complexity than FLASH memories. The new memory cells take advantage of the Thermal Assisted Switching (TAS) writing technique to solve the drawbacks of the more common Field Induced Magnetic Switching writing technique. The CMOS circuit structures to implement the main components for reading and writing the MTJ cells have been developed, characterized and evaluated. A scaled down prototype of a coarse grain reconfigurable array that employs the TAS-MRAM elements as configuration memory has been designed and electrically simulated pre- and post- layout. The results obtained for all the circuit elements, namely the storage cells and the current generators, indicate that the new configuration memory cells can provide a very promising technological solution for run-time reconfigurable hardware devices. The prototype has been manufactured using a standard process 0.35μm 4-Metal CMOS process technology and should be under test in the foreseeable future.
Źródło:
International Journal of Microelectronics and Computer Science; 2010, 1, 1; 31-36
2080-8755
2353-9607
Pojawia się w:
International Journal of Microelectronics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of acute low back pain in women after treatment with interferential current
Autorzy:
Serafim, A.
Rabel, J.
Neves, M.
Da Silva, T.S.
Bertolini, G.R.F.
Powiązania:
https://bibliotekanauki.pl/articles/3294.pdf
Data publikacji:
2019
Wydawca:
Instytut Medycyny Wsi
Źródło:
Journal of Pre-Clinical and Clinical Research; 2019, 13, 2
1898-2395
Pojawia się w:
Journal of Pre-Clinical and Clinical Research
Dostawca treści:
Biblioteka Nauki
Artykuł

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