875 resultados para XY CHAIN
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The temperature dependencies of specific heat and spin susceptibility of a coupled dx2-y2 + idxy superconductor in the presence of a weak dxy component are investigated in the tight-binding model (1) on square lattice and (2) on a lattice with orthorhombic distortion. As the temperature is lowered past the critical temperature Tc, first a less ordered dx2-y2 superconductor is created, which changes to a more ordered dx2-y2 + idxy superconductor at Tcl(< Tc). This manifests in two second order phase transitions identified by two jumps in specific heat at Tc and Tc1. The temperature dependencies of the superconducting observables exhibit a change from power-law to exponential behavior as temperature is lowered below Tc1 and confirm the new phase transition. © 1998 Published by Elsevier Science B.V. All rights reserved.
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Pós-graduação em Engenharia de Produção - FEB
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Pós-graduação em Engenharia de Produção - FEB
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Purpose – The purpose of this paper is to investigate how company size and the type of production system affect the adoption of supply chain management (SCM) practices in companies in the electro‐electronics sector in Brazil. Design/methodology/approach – An e‐mail survey of 107 companies associated with the Brazilian Electrical and Electronics Industry Association (ABINEE) was conducted. Statistical techniques were employed to verify the adoption of SCM practices according to the size of the company and its production system. Findings – The major results indicate that the larger the size of the company, the higher the level of adoption of SCM practices, and that the choice of SCM practices depends upon the type of production system implemented. Practical implications – The implications of this study are useful to top management leaders of small and medium‐sized enterprises since the findings enable them to identify the most common practices adopted by either large‐, medium‐ or small‐sized companies in order to benchmark the level of adoption of SCM practices. Production managers can also benefit from this study by identifying the SCM practices that may support certain production systems.
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The objective of this research is to examine if the environmental management evolution is positively related towards the adoption of green supply chain management practices (GSCM) by companies in the electronics sector in Brazil. To reach this objective, a quantitative research was conducted by survey with 100 companies in the electronics sector in Brazil. The collected data were processed using descriptive statistics, Exploratory Factor Analysis and Structural Equation Modeling. The most important results are: in the sample, GSCM practices to the recovery of investment, as the resale of scrap and other waste materials, and the adequacy with legislation and auditing, obtained high scores; and research hypothesis (H1) was confirmed and considered statistically valid, indicating that, in fact, the evolution of environmental management influences the adoption of GSCM practices.