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71.
T. Diana L v. A. de Macedo‐Soares Ph.D. Paulo Jacinto Pastor‐Braga B.Sc. 《Information Technology for Development》2013,19(4):453-485
Abstract This article gives an account of the results of a case study undertaken at a pioneer and particularly prominent firm in the Brazilian computer industry: COBRA — Computadores e Sistemas Brasileiros SA. The study is part of a research project1 whose main goal is the identification of viable organizational and technological options that could enhance the performance of firms in the Brazilian electro‐electronics industry. Among the more important findings, it was observed that the firm has the potential to evolve to a more flexible structure, in keeping with the new requirements of the probable future market scenarios within its sector. Everything indicated, however, that the main constraining factors for bringing about such a structure were connected with the firm's culture and beliefs and with the indirect influence of the National Policy of Information Technology upon these. An hypothesis was put forward for an organizational model, and the necessary supportive computerized technology, which could be particularly appropriate in view of the impending deregulation, of the Brazilian computer industry. Also, in the scope of the current discussion on the restructuring of this industry in terms of a greater concentration, an alternative to the prevailing school of thought was proposed, and for whose success the organizational model at issue purports to be particularly relevant. 相似文献
72.
Mara Soares da SilvaFranklin L. Nobrega Ana Aguiar-RicardoEurico J. Cabrita Teresa Casimiro 《The Journal of Supercritical Fluids》2011,58(1):150-157
This work reports the development of a novel class of affinity co-polymeric materials using supercritical fluid technology. Polymeric materials with molecular recognition to flufenamic acid, were first synthesized in supercritical carbon dioxide (scCO2) using the drug as template. Molecularly imprinted co-polymers of methacrylic acid (MAA) or N-isopropyl acrylamide (NIPAAm) crosslinked with ethylene glycol dimethacrylate (EGDMA) were synthesized using different crosslinking degrees and template:monomer ratios, at 65 °C and 21 MPa. High-pressure NMR experiments confirmed that the nature of the interactions between the drug and the functional monomers during the polymerization step are mainly hydrogen bonds. scCO2-assisted impregnation revealed that the imprinted matrices were able to uptake higher amounts of flufenamic acid. This effect was particularly evidenced in the more crosslinked matrices, with P(MAA-EGDMA) imprinted copolymers binding up to 101.5 mg drug/g polymer against only 50.5 mg/g in the non-imprinted copolymer. In vitro drug delivery experiments showed that imprinted co-polymers release the drug in a more sustained way than the corresponding non-imprinted matrices. Overall it was shown that supercritical fluid technology is a viable approach for the development of self-assembly molecular recognition polymers with potential application in controlled drug delivery systems. 相似文献
73.
M. Adak C. Guedes Soares 《The International Journal of Advanced Manufacturing Technology》2014,71(1-4):699-710
Effects of three different plate boundary constraints on the residual stress field and deformation are investigated numerically during butt-joint welding. For the numerical solution of the heat transfer equations, the finite element method is used to predict the temperature profile as well as residual stress field due to three different plate boundary conditions. The distortion of the welded plate is modeled as a nonlinear problem in geometry and material, adopting a finite element solution based upon the thermo–elastic–plastic large deflection theory. High-strength shipbuilding steel AH36 with temperature-depending material properties and nonlinear stress–strain material properties (bilinear isotropic hardening option uses the von Mises yield criteria) are assumed for the numerical analysis. For verifying the results, the temperature profile is compared with the result obtained in a previous research. In the mechanical analysis, three different boundary conditions are applied. Effects of plate thickness, plate width, and mesh model on the residual stress with boundary constraint are studied. 相似文献
74.
Susane Moreira Machado Anderson Oliveira Lobo Ariel Bueno Loureiro Sapucahy Fernanda Roberta Marciano Evaldo Jose Corat Newton Soares da Silva 《Materials science & engineering. C, Materials for biological applications》2011,31(7):1614-1617
For the first time, we show that Tritrichomonas foetus can adhere on superhydrophilic vertically aligned carbon nanotubes (VACNT) films. Scanning electron microscopy shows an unusual adhesion with a higher membrane filopodium projection in all directions, directly attached to superhydrophilic VACNT tips. 相似文献
75.
Thales Leandro Coutinho de Oliveira Rodrigo de Araújo Soares Roberta Hilsdorf Piccoli 《Meat science》2013
The antimicrobial effect of oregano (Origanum vulgare L.) and lemongrass (Cymbopogon citratus (DC.) Stapf.) essential oils (EOs) against Salmonella enterica serotype Enteritidis in in vitro experiments, and inoculated in ground bovine meat during refrigerated storage (4 ± 2 °C) for 6 days was evaluated. The Weibull model was tested to fit survival/inactivation bacterial curves (estimating of p and δ parameters). The minimum inhibitory concentration (MIC) value for both EOs on S. Enteritidis was 3.90 μl/ml. The EO concentrations applied in the ground beef were 3.90, 7.80 and 15.60 μl/g, based on MIC levels and possible activity reduction by food constituents. Both evaluated EOs in all tested levels, showed antimicrobial effects, with microbial populations reducing (p ≤ 0.05) along time storage. Evaluating fit-quality parameters (RSS and RSE) Weibull models are able to describe the inactivation curves of EOs against S. Enteritidis. The application of EOs in processed meats can be used to control pathogens during refrigerated shelf-life. 相似文献
76.
Ana S.V. FerreiraCátia M.C. Soares Filipe M.H.L.R. FigueiredoFernando M.B. Marques 《International Journal of Hydrogen Energy》2011,36(5):3704-3711
Composite ionic conductors for fuel cells were produced by combination of one ceria-based ceramic electrolyte and various mixtures of Na and Li carbonates, using several processing routes. These materials were characterized by impedance spectroscopy, scanning electron microscopy with energy dispersive spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy with attenuated total reflectance. The chemical composition of the mixed carbonates and the processing route were influential in the development of impressive conductivity levels (close to 0.1 S/cm) at modest temperatures (below 600 °C), suggesting a complex role of chemical composition (Na/Li ratio), phase composition (solid/liquid ratio), processing route (mechanothermal history) and microstructure. Furthermore, exposure to humidity showed formation of OH groups. Such hydrogenated species are believed to increase the complexity of the global surface processes and charge transport mechanisms where several native and foreign species may play a significant role. 相似文献
77.
78.
Cooking and texture properties of gluten‐free fettuccine processed from defatted flaxseed flour and rice flour 下载免费PDF全文
Camila M. A. de Moura Manoel S. Soares Júnior Fernanda A. Fiorda Márcio Caliari Rosângela Vera Maria V. E. Grossmann 《International Journal of Food Science & Technology》2016,51(6):1495-1501
Nonconventional raw materials have been applied in gluten‐free pasta, to meet the demand of people with coeliac disease. The objective of this study was to evaluate the cooking properties and texture of pasta formulated with rice flour, defatted flaxseed flour and pregelatinised mixed flour of rice and flaxseed (80:20). For this experiment, simplex design was used. Cooking properties and texture were found within the quality limits established for this type of product. The pasta with the most desirable properties (short optimum cooking time (OCT), less solid loss (SL) and intermediate mass increase (MI)) was that one formulated with 43 g 100 g?1 of pregelatinised flour, 47 g 100 g?1 of rice flour and 10 g 100 g?1 of defatted flaxseed flour. This formulation can be characterised as a food rich in dietary fibre and of high nutritional value. 相似文献
79.
Filomena O. Soares Manuel J. Sepúlveda Sérgio Monteiro Rui M. Lima José Dinis-Carvalho 《Mechatronics》2013,23(8):987-996
This paper presents a new line of project based learning in the School of Engineering of University of Minho: the Innovation and Entrepreneurship Integrated Project (IEIP). Four groups, each one composed of students from different engineering integrated master courses – Mechanical, Industrial Electronics and Computers, Polymer, Industrial Management – compete against each other in developing or improving commercial products manufactured by actual industries. There have been so far five editions of the IEIP, with five different companies and five diverse products, however, all these products included components that required knowledge from all the engineering courses involved. Only with the cooperation between the students of the various courses that compose each multidisciplinary team, the success is attainable. As each student has to deal with various engineering scopes, students’ technical skills are greatly enlarged and they acquire a multidisciplinary knowledge that was not possible in another way. Their soft skills like project management, teamwork, communication ability and personal development, which are valuable requisites for their future employers, are also improved. The participating industries also take advantage of the project: the groups competing against each other act as a multiskilled work force, actually making proposals capable of improving their products, their efficiency, and reducing costs. 相似文献
80.
Improvement on Sliding Wear Behavior of Al/Cast Iron Tribopair by CNT's Reinforcement of an Al Alloy
Oscar Carvalho Mihaela Buciumeanu Delfin Soares Jose Gomes Filipe S. Silva 《摩擦学汇刊》2013,56(4):643-653
The results presented in this work show the wear characterization of Al-Si matrix composites reinforced by multiwall carbon nanotubes (MWCNTs) under dry reciprocating sliding conditions against a grey cast iron (GCI) The wear resistance is investigated as a function of the carbon nanotube (CNT) content that varied from 2 to 6 wt%. The results demonstrated that the CNT content plays a relevant role in the wear behavior by substantially reducing the wear loss of Al-Si CNT composites. Further, it reduces the wear loss of the grey cast iron counterface. A physical model able to explain the improved behavior in both mating materials is depicted from experimental results. 相似文献