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91.
This paper addresses the food distribution decision from a wholesaler's perspective, as the wholesalers are often faced with thorny issues such as when, where, how to deliver products at the lowest costs to best satisfy the retailers’ changing needs. This research relies on a distribution problem encountered at Northern Grocery Company in Beijing as an example to develop a two-stage solution procedure and subsequent computer-enabled programs for identifying efficient vehicle routing alternatives. The solution process, which integrates heuristic search algorithms and an integer programming model, can be applied to a wide range of distribution problems with specified route durations and a circular transportation network structure as exemplified by City of Beijing. 相似文献
92.
Xueqing Zhang 《Expert systems with applications》2009,36(4):7519-7527
Best value is the ultimate goal in the development of infrastructure projects through public private partnerships. This necessitates a best value approach in selecting the right private partner (i.e., the concessionaire) that involves evaluating alternative concessionaires against multiple conflicting criteria of varying degrees of importance and uncertainty. Correspondingly, this paper has developed a quantitative best value concessionaire selection system. The essence of this system lies in (1) the establishment of four-package evaluation criteria that can effectively measure the concessionaire’s capability and “predict” its future performance toward achieving the government’s best value objectives and (2) the development of a fuzzy-composite scoring and ranking method that ensures the right “tradeoff” between these criteria by relatively weighting fuzzy scores and logically aggregating evaluation results. This system would not only provide the government integrated assessments of alternative concessionaires so as to award the contract to the right concessionaire whose proposal is perceived to be able to maximize the outcome of the project, but also satisfy the requirements of the legal decision in order to withstand legal challenges concerning the public contract awarded in a best value approach. A hypothetical case study is provided to demonstrate the application of this best value concessionaire selection system. 相似文献
93.
Research suggests that less than 5 h sleep in the 24 h prior to work and/or more than 16 h of wakefulness can significantly increase the likelihood of fatigue-related impairment and error at work. Studies have also shown exponential safety declines with time on shift, with roughly double the likelihood of accident or injury after 10 h relative to the first 8 h. While it is acknowledged that reduced sleep, increased wakefulness and longer work hours produce work-related fatigue, few studies have examined the impact of workload on this relationship. Studies in the rail industry have focused on drivers. This study investigated fatigue in a large sample of Australian Rail Industry Employees. Participants were from four companies (n = 90: 85m, 5f; mean age 40.2 ± 8.6 y). Data was analysed for a total of 713 shifts. Subjects wore wrist actigraphs and completed sleep and work diaries for 14-days. They also completed the Samn–Perelli Fatigue Scale at the beginning and end of shifts, and the NASA-TLX workload scale at least twice during each shift. Average (±SD) sleep length (7.2 ± 2.6 h), prior wake at shift end (12.0 ± 4.7 h), shift duration (8.0 ± 1.3) and fatigue (4.1 ± 1.3, “a little tired, less than fresh”) were within limits generally considered acceptable from a fatigue perspective. However, participants received 5 h or less sleep in the prior 24 h on 13%, were awake for at least 16 h at the end of 16% and worked at least 10 h on 7% of shifts. Subjects reported that they felt “extremely tired, very difficult to concentrate,” or “completely exhausted, unable to function effectively” on 13% of shifts. Sleep length (OR = 0.88, p < 0.01), shift duration (OR = 1.18, p < 0.05), night shift (REF = morning shift, OR = 2.12, p < 0.05) and workload ratings (OR = 1.2, p < 0.05) were significant predictors of ratings of extreme tiredness/exhaustion (yes/no). While on average, sleep loss, extended wakefulness, longer work hours and work-related fatigue do not appear problematic in this sample, there is still a notable percentage of shifts that are likely to be associated with high levels of work-related fatigue. Given the size of the Australian Rail Industry, with thousands of shifts occurring each day, this is potentially of operational concern. Further, results indicate that, in addition to sleep length, wakefulness and work hours, workload significantly influences fatigue. This has possible implications for bio-mathematical predictions of fatigue and for fatigue management more generally. 相似文献
94.
研究构建大型煤化工甲醇精馏过程仿真平台问题.大型煤化工甲醇精馏过程操作复杂,为了能够更好地分析和预测该过程,本文开发了基于工艺过程机理模型的仿真系统.仿真系统的底层是流程模拟文件,提供过程机理模型和计算平台;顶层是仿真界面,提供人机交互窗口;二者通过Visual Basic接口程序链接.此仿真系统可以为实际的精馏操作提... 相似文献
95.
炼油生产调度专家系统的应用研究 总被引:4,自引:1,他引:3
基于知识的优化设计应用于炼油化工厂,采用专家系统技术将生产中成功的经验和领域专家的知识组织起来,协调并参与数学规划建模过程,优化编排调度作业计划,并进行优化控制和管理.文章结合大型炼油厂的生产实际,探索智能化的管控一体化的新模式. 相似文献
96.
熊刚 《计算机工程与应用》2000,(11)
文章首先提出了流程工业及其CIMS中的各种优化问题;;小结了各种解决优化问题的求解技术.在此基础上提出了一种基于多级优化的一种流程工业CIMS结构.最后;;作者提出了一种解决流程工业CIMS多目标优化问题的最大熵优化技术 相似文献
97.
本文分析了我国信息产业中的知识产权现状与问题,提出开展信息产业知识产权信息跟踪与预警分析、专业人才的培养和知识产权宣传普及等对策,提高产业核心竞争力。 相似文献
98.
QU Shou-ning LIU Zhao-lian CUI Guang-qiang WANG Qin 《通讯和计算机》2008,5(9):74-79
Fluid industry's production takes on high complexity, strong association, non-linear and indeterminacy. To find important parameters which influence production process, provide theoretical basis for process control of fluid industry's production and make the production process control more exact, we propose a flexible neural tree model in this paper. The model can be created based on predeflned information set. The structure and parameters of flexible neural tree are optimized by probabilistic incremental program evolution and simulation annealing respectively. We take production process of decomposed kiln---one of important cement's processes---as an example. The result indicates that the proposed model is greatly efficient. 相似文献
99.
王世伟 《数码设计:surface》2008,(4):126-127
在山东工艺美术学院的工业设计学院工业陶瓷专业建设伊始,笔者结合国内外的优秀教学经验及成果,以及建该专业的总体指导思想,对将来的工业陶瓷设计教育做出相关的展望,提出一些关于该专业实践教学、产学研和综合教育资源等方面的看法,视为在教学前的一次总结报告,旨在更好地引导教学。 相似文献
100.
陈毓 《数码设计:surface》2008,(1):134-136
本文介绍了一种基于快速成型技术的警用小型电子产品的工业设计方法。与传统设计方法相比较,该方法在创新设计理念、缩短产品研制周期、保证产品质量等方面都有了重大突破。同时,本文以电子护照读写机具设计为例,详细阐述了应用这种方法进行警用小型电子产品设计的方法和流程,并将该方法与传统设计方法进行了详细的分析和比较。 相似文献