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51.
Research in object-oriented manufacturing simulations:an assessment of the state of the art 总被引:1,自引:0,他引:1
S. Narayanan D.A. Bodner T. Govindaraj L.F. Mcginnis C.M. Mitchell U. Sreekanth 《IIE Transactions》1998,30(9):795-810
Object-oriented programming (OOP) has been revolutionizing software development and maintenance. When applied to simulation of manufacturing systems, OOP also provides an opportunity for developing new ways of thinking and modeling. In this paper, we identify existing large-scale, persistent OOP-based research efforts focusing on manufacturing system simulation, and present an integrating framework for discussing the associated modeling abstractions, implementation strategies, common themes, and distinctive features. The goal is to identify the fundamental research and application issues, assess the current state of the art, and identify key research needs. 相似文献
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We present a technique for approximating isotropic BRDFs and precomputed self-occlusion that enables accurate and efficient prefiltered environment map rendering. Our approach uses a nonlinear approximation of the BRDF as a weighted sum of isotropic Gaussian functions. Our representation requires a minimal amount of storage, can accurately represent BRDFs of arbitrary sharpness, and is above all, efficient to render. We precompute visibility due to self-occlusion and store a low-frequency approximation suitable for glossy reflections. We demonstrate our method by fitting our representation to measured BRDF data, yielding high visual quality at real-time frame rates. 相似文献
55.
In this paper a methodology for the use of temporal logic as an executable imperative language is introduced. The approach, which provides a concrete framework, calledMetateM, for executing temporal formulae, is motivated and illustrated through examples. In addition, this introduction provides references to further, more detailed, work relating to theMetateM approach to executable logics. 相似文献
56.
《Computer Communications》2007,30(1):132-143
In the paper, we proposed a resource allocation method employing maximal compatible cliques to make use of channel bandwidth as efficiently as possible in a TD-CDMA system. Furthermore, the strength of beacon signals was also measured to decide whether or not to reserve resources for hand-off users, in order to reduce their dropping probabilities. Finally, we conducted several experiments to validate that our method could make use of the finite resources efficiently, thereby revealing better blocking probabilities and dropping probabilities than other methods. 相似文献
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《Computers in Industry》2007,58(8-9):844-854
This paper examines the effectiveness of the implementation of enterprise resource planning (ERP) in improving service quality in the Taiwanese semiconductor industry by assessing the expectations and the perceptions of service quality from the perspectives of both upstream manufacturers and downstream customers. The study first establishes a modified service quality gap model incorporating: (i) the downstream customers’ expectations and perceptions, and (ii) the upstream manufacturers’ perceptions of the customers’ expectations and perceptions. An empirical study by questionnaire survey is then undertaken to investigate the gaps proposed in the research model. The results show that service quality gaps do exist in the Taiwanese semiconductor industry between upstream manufacturers that are implementing ERP and their downstream customers. The study shows that the proposed model provides valuable guidance to manufacturers with respect to the prevention, detection, and elimination of the demonstrated service quality gaps. The model thus helps manufacturers to evaluate the contribution of various ERP modules to improved customer satisfaction with service quality and also provides guidance on improvement strategies to enhance service quality by eliminating quality gaps. 相似文献
59.
《Computer Communications》2007,30(1):122-131
Given the increasing adoption of DWDM networking technology, there is now a growing need to address distributed inter-domain lightpath provisioning issues. Although inter-domain provisioning has been well studied for packet/cell-switching networks, the wavelength dimension presents many additional challenges. To address this challenge, a detailed hierarchical routing GMPLS-based framework for provisioning all-optical and opto-electronic multi-domain DWDM networks is presented. The scheme adapts various topology abstraction schemes to improve routing scalability and lower inter-domain blocking probabilities. Related inter-domain lightpath RWA and signaling schemes are also tabled. Performance analysis results are also presented to demonstrate the effectiveness of the proposed mechanisms along with directions for future research work. 相似文献
60.
动力电缆温度监测是可以及时发现电缆线路过热点位置和检测运行线路的绝缘状态,从而保障电缆安全稳定运行的技术措施。针对电缆过热事故的主要原因和特点,提出采用分布式光纤测温技术对电缆沿线温度进行监测预警,给出了分布式光纤测温系统的原理、组成和光缆布设方案,此系统对保证电力系统的安全运行有重要意义。 相似文献