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Tytuł:
Full-fledged temporal processing : bridging the gap between deep linguistic processing and temporal extraction
Autorzy:
Costa, F.
Branco, A.
Powiązania:
https://bibliotekanauki.pl/articles/103861.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Instytut Podstaw Informatyki PAN
Tematy:
temporal processing
temporal extraction
tense
aspect
hybrid approaches
deep linguistic processing
shallow linguistic processing
Opis:
The full-fledged processing of temporal information presents specific challenges. These difficulties largely stem from the fact that the temporal meaning conveyed by grammatical means interacts with many extra-linguistic factors (world knowledge, causality, calendar systems, reasoning). This article proposes a novel approach to this problem, based on a hybrid strategy that explores the complementarity of the symbolic and probabilistic methods. A specialized temporal extraction system is combined with a deep linguistic processing grammar. The temporal extraction system extracts eventualities, times and dates mentioned in text, and also temporal relations between them, in line with the tasks of the recent TempEval challenges; and uses machine learning techniques to draw from different sources of information (grammatical and extra-grammatical) even if it is not explicitly known how these combine to produce the final temporal meaning being expressed. In turn, the deep computational grammar delivers richer truth-conditional meaning representations of input sentences, which include a principled representation of temporal information, on which higher level tasks, including reasoning, can be based. These deep semantic representations are extended and improved according to the output of the aforementioned temporal extraction module. The prototype implemented shows performance results that increase the quality of the temporal meaning representations and are better than the performance of each of the two components in isolation.
Źródło:
Journal of Language Modelling; 2013, 1, 1; 97-154
2299-856X
2299-8470
Pojawia się w:
Journal of Language Modelling
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparative study on the performance of radiation detectors from the HgI2 crystals grown by different techniques
Autorzy:
Martins, J. F. T.
Costa, F. E.
dos Santos, R. A.
de Mesquita, C. H.
Hamada, M. M.
Powiązania:
https://bibliotekanauki.pl/articles/146916.pdf
Data publikacji:
2012
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
crystal growth
iodide mercury crystal
physical vapor transport (PVT)
radiation detector
semiconductor crystal
Opis:
In this work, the establishment of a technology for HgI2 purification and crystal growth is described, aiming at a future application of this crystal as a room temperature radiation semiconductor detector. Two methods of crystal growth were studied in the development of this work: (1) physical vapor transport (PVT) and (2) saturated solution from dimethylsulphoxide (DMSO) complexes. In order to evaluate the crystals obtained using each of these methods, systematic measurements were carried out for determining the stoichiometry, structure, orientation, surface morphology and impurity of the crystal. The influence of these physicochemical properties of the crystals developed was evaluated in terms of their performance as a radiation detector. The best response to radiation was found for the crystals grown by the PVT technique. Significant improvement in the performance of HgI2 radiation detector was found, purifying the crystal by means of two successive growths by the PVT technique.
Źródło:
Nukleonika; 2012, 57, 4; 555-562
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of an automation system for iodine-125 brachytherapy seed encapsulated by Nd:YAG laser welding
Autorzy:
Somessari, S. L.
Feher, A.
Sprenger, F. E.
Rostelato, M. E. C. M.
da Costa, F. E.
Calvo, W. A. P.
Powiązania:
https://bibliotekanauki.pl/articles/147664.pdf
Data publikacji:
2011
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
iodine-125 seeds
prostate cancer
brachytherapy
Nd:YAG laser welding
Opis:
The aim of this work is to develop an automation system for iodine-125 radioactive seed production by Nd:YAG laser welding, which has been used successfully in low dose rate (LDR) brachytherapy treatment. This small seed consists of a welded titanium capsule, with 0.8 mm in diameter and 4.5 mm in length, containing iodine-125 adsorbed onto a silver rod. The iodine-125 seeds are implanted into the human prostate to irradiate the tumor for cancer treatment. Nowadays, the Radiation Technology Center, at Institute for Nuclear and Energy Research, Săo Paulo, Brazil (IPEN-CNEN/SP) imports and distributes 36,000 iodine-125 seeds per year, for the clinics and hospitals in the country. However, the Brazilian market potential is now over 8,000 iodine-125 seeds per month. The local production of these iodine-125 radioactive sources became a priority for the Institute, in order to reduce the price and the problems of prostate cancer management. It will permit to spread their use to a larger number of patients in Brazil. On the other hand, the industrial automation plays an important role for iodine-125 seeds in order to increase the productivity, with high quality and assurance, avoiding human factors, implementing and operating with good manufacturing practices (GMP). The technology consists of appliance electronic and electro-mechanical parts and components to control machines and processes. The automation system technology for iodine-125 seed production developed in this work was mainly assembled employing a programmable logic controller (PLC), a stepper motor, an Nd:YAG laser welding machine and a supervisory. The statistical repeatability of correctly encapsulated sealed sources with this automation system is greater than 95 per cent.
Źródło:
Nukleonika; 2011, 56, 4; 369-374
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of an irradiation system for a small size continuous run multipurpose gamma irradiator
Autorzy:
Calvo, W. A. P.
Rela, P. R.
Napolitano, C. M.
Kodama, Y.
Omi, N. M.
da Costa, F.
de Andrade e Silva, L. G.
Powiązania:
https://bibliotekanauki.pl/articles/148041.pdf
Data publikacji:
2009
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
multipurpose irradiator
gamma irradiator
compact irradiator
cobalt-60 irradiator
gamma facility
Opis:
The Radiation Technology Center from IPEN-CNEN/SP, Brazil, developed a revolutionary design and national technology, a small-sized continuous run and multipurpose industrial gamma irradiator, to be used as a demonstration facility for manufacturers and contract service companies, which need economical and logistical in-house irradiation system alternatives. Also, to be useful for supporting the local scientific community on development of products and process using gamma radiation, assisting the traditional and potential users on process validation, training and qualification of operators and radioprotection officers. The developed technology for this facility consists of a continuous tote box transport system, comprising a single concrete vault, where the automated transport system of products inside and outside of the irradiator utilizes a rotating door, integrated with the shielding, avoiding the traditional maze configuration. Covering 76 m2 of floor area, the irradiator design is a product overlap sources and the maximum capacity of cobalt-60 wet sources is 37 PBq. The performed qualification program of this multipurpose irradiator was based on AAMI/ISO 11137 standard, which recommends the inclusion of the following elements: installation and process qualification. The initial load of the multipurpose irradiator was 3.4 PBq with 13 cobalt-60 sources model C-188, supplied by MDS Nordion – Canada. For irradiator dose optimization, the source distribution was done using the software Cadgamma developed by IPEN-CNEN/SP. The polymethylmetacrylate (PMMA) dosimeter system, certified by the International Dose Assurance Service (IDAS) of the International Atomic Energy Agency (IAEA) was used for irradiator dose mapping. The economic analysis, performance concerning with dose uniformity and cobalt-60 utilization efficiency were calculated and compared with other commercial gamma irradiators available on the market.
Źródło:
Nukleonika; 2009, 54, 2; 93-97
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Expert System Coupled With a Hierarchical Structure of Fuzzy Neural Networks for Fault Diagnosis
Autorzy:
Calado, J. M. F.
Costa, I. S.
Powiązania:
https://bibliotekanauki.pl/articles/908283.pdf
Data publikacji:
1999
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
rozpoznanie błędu
wykrywanie błędu
system ekspertowy
sieć neuronowa rozmyta
fault diagnosis
fault detection
fault isolation
shallow knowledge
deep knowledge
expert system
fuzzy neural network
abrupt faults
incipient faults
Opis:
An on-line fault diagnosis system, designed to be robust to the normal transient behaviour of the process, is described. The overall system consists of an expert system cascade with a hierarchical structure of fuzzy neural networks, corresponding to a multi-stage fault detection and isolation system. The fault detection is performed through the expert system by means of fault detection heuristic rules, generated from deep and shallow knowledge of the process under consideration. If a fault is detected, the hierarchical structure of fuzzy neural networks starts and it performs the fault isolation task. The structure of this diagnosis system was designed to allow for the diagnosis of single and multiple simultaneous abrupt and incipient faults from only single abrupt fault symptoms. Also, it combines the advantages of both fuzzy reasoning and neural networks learning capacity. A continuous binary distillation column has been used as a test bed of the current approach. Single, double and triple simultaneous abrupt faults, as well as incipient faults, have been considered. The preliminary results obtained show a good accuracy, even in the case of multiple faults.
Źródło:
International Journal of Applied Mathematics and Computer Science; 1999, 9, 3; 667-687
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nonlinear elastic brittle damage: numerical solution by means of operator split methods
Autorzy:
Pires-Domingues, S.M.
Costa-Mattos, H.
Rochinha, F.A.
Powiązania:
https://bibliotekanauki.pl/articles/279553.pdf
Data publikacji:
1999
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
damage mechanics
finite elements
splitting technique
Opis:
The avoid the loss of well-posedness in the post localization range, some continuum damage theories for elastic materials introduce higher order gradients of the damage variable into constitutive model. Although such theories allow for mathematically correct modelling of the strain localization phenomena, they are usually considered to be very complex to handle from the numerical point of view. The present work deals with the numerical implementation of a gradient-enhanced damage theory for elastic materials. A simple numerical technique, based on the finite element method, is proposed to approximate the solution to the resulting nonlinear mathematical problems. The coupling between damage and strain variables is circumvented by means of a splitting technique.
Celem poprawności sformułowania problemu w pewnych teoriach zniszczenia do modelu konstytutywnego materiałów sprężystych wprowadza się wyższe gradienty zmiennych opisujących zniszczenie. Chociaż teorie takie umożliwiają matematycznie poprawne modelowanie zjawisk lokalizacji odkształceń, to z punktu widzenia numeryki stosowanie ich uważa się zwykle za bardzo skomplikowane. W niniejszej wersji przedstawiono zastosowanie numeryczne teorii zniszczenia z wyższymi gradientami do materiałów sprężystych. Do przybliżonego rozwiązania otrzymanych nieliniowych zadań matematycznych zaproponowano prostą metodę numeryczną opartą na metodzie elementów skończonych. Użycie metody operatorowej pozwoliło uniknąć sprężenia między zmiennymi opisującymi zniszczenie i odkształcenie.
Źródło:
Journal of Theoretical and Applied Mechanics; 1999, 4; 847-861
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation modelling of Vitória-Minas closed-loop rail network
Modelagem de simulação do circuito fechado da ferrovia Vitória Á Minas
Autorzy:
Faria, C. H. F. de
Cruz, M. M. da Costa
Powiązania:
https://bibliotekanauki.pl/articles/375477.pdf
Data publikacji:
2015
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
railway
simulation
closed loop
heavy haul
transportation of iron ore
rolling stock
kolej żelazna
symulacja
pętla zamknięta
transport rud żelaza
tabor kolejowy
Opis:
This paper presents a closed loop simulation model that represents the mining logistics chain of the Vitória Minas Railway (VMR), Brazil. The simulator includes the loading process, circulation of loaded trains, unloading of ores for external and internal markets and the distribution of empty trains for new loads. General cargo and passengers trains are also included in the model, which, along with the queues formed in the circulation and the preventive and corrective maintenance of rolling stock, tracks and equipment, interfere with the transportation of iron ore. The primary objective of the iron ore transport is to meet the daily loading and unloading schedules and minimize queues by maximizing the operations at the loading and unloading points. The VMR simulator developed uses macro-mesoscopic approach with Monte Carlo simulation. To validate the simulator, we used actual data of the railway and compared with reality. We obtained a very good adhesion to the value of 2.9% for the validation scenario (Scenario 1) and 3.4% for the scenario with reducing the number of lots of wagons (Scenario 2). We concluded with this simulation that it is possible to reduce the number of GDE wagons without reducing the current level of productivity of the rail system.
Este artigo apresenta o modelo de simulação do circuito fechado da rede logística de minério de ferro da ferrovia Vitória Á Minas (VMR), Brasil. O simulador inclui o processo de carregamento, circulação dos trens carregados, descarregamento para os mercados externos e internos e a distribuição dos trens vazios para novos carregamentos. Os trens de carga geral e de passageiros também foram incluídos no modelo, bem como suas filas de formação e as manutenções preventivas e corretivas do material rodante, que interferem no transporte do minério de ferro. O principal objetivo do transporte de minério de ferro é atender as programações de carregamento e descarregamento e minimizar as filas maximizando as operações nos pontos de carregamento e descarregamento. O simulador VMR desenvolvido utiliza uma abordagem macro-mesoscópica de simulação de Monte Carlo. Para validar o simulador, foi utilizado dados da ferrovia e comparado com a realidade. Obtivemos uma aderência muito de 2,9% para o cenário de validação (cenário 1) e 3,4% para o cenário com a redução do número de lotes de vagão (cenário 2). Concluímos que com esta simulação é possível reduz o número de lotes de vagões GDE sem reduzir a produtividade da ferrovia.
Źródło:
Transport Problems; 2015, T. 10, z. spec.; 125-139
1896-0596
2300-861X
Pojawia się w:
Transport Problems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Relationship between performance, dry-land power and kinematics in master swimmers
Autorzy:
Espada, M. C.
Costa, M. J.
Costa, A. M.
Silva, A. J.
Barbosa, T. M.
Pereira, A. F.
Powiązania:
https://bibliotekanauki.pl/articles/307228.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
pływanie
kinematyka
energia
master swimmers
kinematic
dry-land power
performance
Opis:
The purpose of the study was to analyze the relationships between sprint swimming performance, dry-land power, and kinematics in master swimmers. Twenty-two male master swimmers were separated in two groups based on their chronological age: (i) 30–39 years and; (ii) 40–49 years. Maximum dry-land power was determined through counter movement jump and 3 kg medicine ball throwing (Hmax and Tmax, respectively). Kinematic determinants of performance were measured during a maximal bout of 15, 25 and 50 m front crawl (T15, T25, T50). Stroke frequency (SF), stroke length (SL) and stroke index (SI) were calculated as kinematical aspects of the stroke. In the 30-39 group, SI25 was correlated to T25 (r = –0.76, p < 0.01, η2 = 0.96), the same was observed between SI50 and T50 (r = –0.83, p < 0.01, η2 = 0.96). Only SI50 was significantly correlated to T50 (r = –0.86, p < 0.01, η2 = 0.97) in the 40–49 years age cohort. In dryland power variables, Hmax and Tmax were only correlated in the younger master swimmers group (r = –0.87, p < 0.01, η2 = 0.97). There were no significant differences (p < 0.05) between younger (30–39 years) and older (40–49 years) swimmers groups in dry-land tests (Hmax 28.5 ± 5.9 vs. 26.5 ± 3.9 cm and Tmax 4.2 ± 1.0 vs. 4.2 ± 1.1 m). Our results suggest that swimming performance in younger master swimmers (30–39 years) seem more dependent on kinematic swimming variables than on strength parameters, which were most related to swimming performance in the older master swimmers (40–49 years).
Źródło:
Acta of Bioengineering and Biomechanics; 2016, 18, 2; 145-151
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling Tyre-Road Noise with Data Mining Techniques
Autorzy:
Freitas, E.
Tinoco, J.
Soares, F.
Costa, J.
Cortez, P.
Pereira, P.
Powiązania:
https://bibliotekanauki.pl/articles/177590.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
tyre-road noise
data mining
model
texture
damping
surface characteristics
Opis:
The research aimed to establish tyre-road noise models by using a Data Mining approach that allowed to build a predictive model and assess the importance of the tested input variables. The data modelling took into account three learning algorithms and three metrics to define the best predictive model. The variables tested included basic properties of pavement surfaces, macrotexture, megatexture, and unevenness and, for the first time, damping. Also, the importance of those variables was measured by using a sensitivity analysis procedure. Two types of models were set: one with basic variables and another with complex variables, such as megatexture and damping, all as a function of vehicles speed. More detailed models were additionally set by the speed level. As a result, several models with very good tyre-road noise predictive capacity were achieved. The most relevant variables were Speed, Temperature, Aggregate size, Mean Profile Depth, and Damping, which had the highest importance, even though influenced by speed. Megatexture and IRI had the lowest importance. The applicability of the models developed in this work is relevant for trucks tyre-noise prediction, represented by the AVON V4 test tyre, at the early stage of road pavements use. Therefore, the obtained models are highly useful for the design of pavements and for noise prediction by road authorities and contractors.
Źródło:
Archives of Acoustics; 2015, 40, 4; 547-560
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Water-based poly(urethane-urea) dispersions —meeting the European Union legislation
Dyspersje wodne poli(uretanowo-mocznikowe) w świetle wymagań prawodawstwa Unii Europejskiej
Autorzy:
Fernandes, I. P.
Costa, M. R.
Ferreira, M. J.
Barreiro, M. F.
Powiązania:
https://bibliotekanauki.pl/articles/947121.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
Tematy:
poly(urethane-urea)
water-based dispersion
European Union legislation
N-methyl-pyrrolidone free products
poli(uretano-mocznik)
dyspersja wodna
prawodawstwo Unii Europejskiej
produkty wolne od N-metylo-pirolidonu
Opis:
This article discusses the synthesis methods of water-based poly(urethane-urea) dispersions (PUD), which over the past few decades have developed a solid reputation for high performance applications, particularly in the field of adhesives and coatings. PUDs are mostly environmentally compatible products since they do not contain or contain only low amounts of volatile organic compounds (VOC). This is an important feature in view of the present environmental policies, where governments and internal agencies are placing emphasis on developing sustainable processes, improving work conditions and reducing emissions of toxic and polluting substances into the atmosphere. In this context, this paper will discuss the main approaches applied to PUD synthesis in order to meet severe environmental restrictions resulting from the EU legislation.
Omówiono metody syntezy dyspersji wodnych poli(uretanowo-mocznikowych) (PUD), które znajdują coraz szersze zastosowanie, szczególnie w produkcji klejów i powłok. PUD są na ogół produktami bezpiecznymi dla środowiska, ze względu na brak lub małą zawartość lotnych związków organicznych (VOC), co jest ważne w świetle obecnej polityki ochrony środowiska. Przedstawione w pracy metody syntezy PUD uwzględniają wymagania wynikające z prawodawstwa Unii Europejskiej w zakresie spełniania surowych ograniczeń środowiskowych.
Źródło:
Polimery; 2015, 60, 9; 536-540
0032-2725
Pojawia się w:
Polimery
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A 3D trabecular bone homogenization technique
Autorzy:
Marques, Marco Costa
Belinha, J.
Oliveira, A. F.
Manzanares Cespedes, M.C.
Natal Jorge, R.M.
Powiązania:
https://bibliotekanauki.pl/articles/27324130.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
fabric tensor
homogenization technique
multiscale
bone
tensor tkaniny
technika homogenizacji
wieloskalowe
kość
Opis:
Purpose: Bone is a hierarchical material that can be characterized from the microscale to macroscale. Multiscale models make it possible to study bone remodeling, inducing bone adaptation by using information of bone multiple scales. This work proposes a computationally efficient homogenization methodology useful for multiscale analysis. This technique is capable to define the homogenized microscale mechanical properties of the trabecular bone highly heterogeneous medium. Methods: In this work, a morphology-based fabric tensor and a set of anisotropic phenomenological laws for bone tissue was used, in order to define the bone micro-scale mechanical properties. To validate the developed methodology, several examples were performed in order to analyze its numerical behavior. Thus, trabecular bone and fabricated benchmarks patches (representing special cases of trabecular bone morphologies) were analyzed under compression. Results: The results show that the developed technique is robust and capable to provide a consistent material homogenization, indicating that the homogeneous models were capable to accurately reproduce the micro-scale patch mechanical behavior. Conclusions: The developed method has shown to be robust, computationally less demanding and enabling the authors to obtain close results when comparing the heterogeneous models with equivalent homogenized models. Therefore, it is capable to accurately predict the micro-scale patch mechanical behavior in a fraction of the time required by classic homogenization techniques.
Źródło:
Acta of Bioengineering and Biomechanics; 2020, 22, 3; 139--152
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Limits in the use of cPTIO as nitric oxide scavenger and EPR probe in plant cells and seedlings
Autorzy:
D'Alessandro, S.
Posocco, B.
Costa, A.
Zahariou, G.
Lo Schiavo, F.
Carbonera, D.
Zottini, M.
Powiązania:
https://bibliotekanauki.pl/articles/80661.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
nitric oxide
scavenger
plant cell
seedling
2-4-carboxyphenyl-4,4,5,5-tetramethyl imidazoline-1-oxyl-3-oxide
fluorescent dye
EPR probe
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:
Insider understanding of country development: a novel application of Optimal Control Theory and Data Envelopment Analysis for benchmarking performance of Chilean and Brazilian companies
Autorzy:
Alves Junior, Paulo Nocera
Yushimito, Wilfredo F.
Gude, Jorge Pereira
Melo, Isotilia Costa
Rebelatto, Daisy Aparecida do Nascimento
Powiązania:
https://bibliotekanauki.pl/articles/14430662.pdf
Data publikacji:
2019-03-27
Wydawca:
Wyższa Szkoła Bankowa we Wrocławiu
Tematy:
Data Envelopment Analysis (DEA)
Optimal Control Theory (OCT)
Dynamic Efficiency
Developing Countries
Inventory Control
Production-Inventory System
Benchmarking
Best Practices.
Opis:
Aim: If companies manage their inventory inefficiently, inventory costs can increase significantly due to shortages, overstocking, and risks. Inventory management is critical for company’s success which, in turn, impacts on countries’ development. This paper aims to investigate the efficiency of inventory control systems of companies from Brazil and Chile through Optimal Control Theory and Data Envelopment Analysis. Design/Research methods: Data was collected from Chilean and Brazilian companies covering different industries in which both countries are mostly dependent A new approach using OCT and DEA is applied for dealing with inventory, production, and demand in Dynamic DEA model to benchmark companies’ production-inventory systems. Conclusions/findings: The results show efficient companies among evaluated industries. Such companies are related mainly to Brazilian commerce and Chilean exports. Based on findings, it was possible to identify patterns and relationship among companies and its inventory management. Originality/value of the article: This paper fills a gap in studies including demand, production, and inventory in Dynamic DEA by using OCT to forewarn unrealistic results and observing companies’ behavior. Besides that, this approach is particularly useful for developing countries in this context, determining benchmarks for the most inefficient firms in each sector. Implications of the research: The results show (1) which companies should focus more on improving inventory management, (2) which companies should be used as benchmarks, and (3) it highlights the reasons of different performance of companies in each country. Limitations of the research: For future research, it is suggested including variables and analysis of social and environmental impacts.
Źródło:
Central European Review of Economics and Management; 2019, 3, 1; 47-93
2543-9472
Pojawia się w:
Central European Review of Economics and Management
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Shot Peening With Glass Microspheres on the Fatigue Behavior of a Low Carbon Steel
Autorzy:
de Lacerda, J. C.
Pereira, I. R.
Costa, J. M. G.
Pinto, J. S.
Souza, H. F. M.
Fonseca, M. A.
Powiązania:
https://bibliotekanauki.pl/articles/352156.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
fatigue
shot peening
Wöhler curve
low carbon steel
glass microspheres
Opis:
The present work has the objective of studying the effect of shot peening with glass microspheres on SAE 1020 steel in its resistance to fatigue. Fatigue tests were carried out by rotary bending with load control and loading on balance in specimens with and without shot peening. A rotation speed of approximately 750 rpm (12.5 Hz) was employed in the fatigue tests. Vickers microhardness tests were performed in order to verify the surface hardening produced by shot peening with glass microspheres. Analysis of the steel surface and fatigue fractures was performed using scanning electron microscopy (SEM). Fatigue tests were performed in order to obtain S-N curves (Wöhler curves). It was observed that shot peening with glass microspheres improved the fatigue strength of the steel at high cycle.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 4; 1513-1518
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 19

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