共查询到20条相似文献,搜索用时 15 毫秒
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A long-term planning model for a large New Zealand dairy company is described. The model presents an integrated view of the company's operation, including transportation and processing. The model used is based on a network formulation, NETPLAN, developed by the authors to carry out the optimisation. NETPLAN is highly flexible, interactive and provides graphical output of the results. The optimisation maximises net revenue based on product prices, variable process costs and variable transport costs subject to factory capacity, product demand and raw material supply constraints. 相似文献
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Sydney C. K. Chu Carrie K. Y. Lin 《The Journal of the Operational Research Society》1994,45(6):696-709
This paper considers the problem of long-term manpower planning on the number of teaching staff for the case of a tertiary institution—the City Polytechnic of Hong Kong (CPHK). Due to the high turnover experienced in recent years, it is found necessary to study the wastage pattern of staff, defined as the number of new appointees who have left CPHK employment, rather than simply addressing just the issue of strength (namely number in post). A cohort analysis technique is therefore applied to characterize statistically the wastage rate as related to the length of service of individual cohorts of staff, being groups of newcomers joining CPHK in the same periods of time. This results in a log-normal model, showing a significant cohort specific effect on the wastage behaviour. Extending this cohort analysis technique, together with double exponential smoothing forecasts, to future retention rates (1 — cumulative wastage rates), a long-term planning model is constructed to study the relation between expected yearly recruitment levels and the target manpower requirements for the future five-year planning horizon. While the idea and model developed here are generally applicable, the present computational results provide valuable decision supports for an actual case study, for CPHK in particular. 相似文献
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为提高供应链的可适应性,提出一种可适应性供应链系统模型,根据规划对供应链实时控制.基于可适应性供应链模式,可以使得供应链稳定性分析的结果和实际执行的结果相匹配.同时提供一种在实时模式下对供应链进行调整的决策制定的工具.提出的理念扩大了对供应链性能调整进行稳定性分析的应用范围,并且可以提高供应链重新配置和调整的决策质量. 相似文献
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针对信用评分的特点,首先对传统的Bagging算法进行改进,然后基于不同的基分类器构建多个改进的Bagging组合模型,最后根据一种全新的方式将其组合,得到双层组合模型.通过实证分析得出以下结论:一、与原Bagging算法相比,改进算法能有效降低第二类错误率;二、与单层组合模型相比,多层组合模型能进一步降低第二类错误率和损失率. 相似文献
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枚举法在制定生产计划中的应用 总被引:1,自引:0,他引:1
赵学慧,赵瑛.枚举法在制定生产计划中的应用,数理统计与管理,1997,16(1),16~18.本文通过用枚举法制定生产计划的实例,向管理人员介绍计算线性规划最优解的一种简单而易行的方法 相似文献
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M. Cirinà 《The Journal of the Operational Research Society》1978,29(6):565-575
The operational value of the mathematical models used in regional or urban planning is mainly dependent upon the possibility of adequate calibration so as to make them actually represent the social and economic problem under study. In this paper we give a formulation of the calibration problem for a singly constrained exponential model, use it to calibrate a specific model that is actually being used to plan the development of a large Italian town, and obtain results that improve by about 30% a standard currently used calibration procedure. 相似文献
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利用线性代数理论中的厄米特二次型和若当标准形研究一类直接控制系统的绝对稳定性问题.进一步发展了控制系统稳定性理论中最近发展起来的一种新的研究方法──降维法.得到了用参数表示的代数形式的绝对稳定性的判别准则. 相似文献
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P. M. Lewy 《The Journal of the Operational Research Society》1979,30(12):1085-1095
Planning the operations of a colliery in the medium term requires management to produce a statement of proposed layout of faces and deployment of men. A computer program was developed to calculate the outcome of implementing a particular plan at a hypothetical colliery. This formed the basis of a competitive syndicate exercise at the Staff College of the National Coal Board. The concept was then extended to real colliery planning, to allow planners and managers to consider a wider set of options than current manual methods permit. The paper describes the common approach and discusses the modifications that were necessary to achieve results quickly enough to influence colliery planning decisions. 相似文献
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C. V. Rao S. J. Wright J. B. Rawlings 《Journal of Optimization Theory and Applications》1998,99(3):723-757
We present a structured interior-point method for the efficient solution of the optimal control problem in model predictive control. The cost of this approach is linear in the horizon length, compared with cubic growth for a naive approach. We use a discrete-time Riccati recursion to solve the linear equations efficiently at each iteration of the interior-point method, and show that this recursion is numerically stable. We demonstrate the effectiveness of the approach by applying it to three process control problems. 相似文献
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本文以知识溢出的地方化(localization)特性为前提条件,从空间视点切入,首次运用负二项回归模型实证考察了中国制造业区域集聚对技术创新的影响。通过最大似然估计得出的结果表明,制造业区域集聚之技术创新效应非常显著。这一结论也得到了对高创新行业和高集聚行业拓展回归分析的支持。研究还显示,FDI对高创新行业的技术创新作用并不显著,反而出现了内资企业向外资企业逆向技术扩散的可能。 相似文献
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经济增长与技术进步的关系历来是国内外学者关心的热门问题.本文研究了经济增长与技术进步的关系,总结了技术进步的测算方法,提出了一个基于投资控制模型的测算技术进步的方法. 相似文献
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研究猫在自由下落时姿态运动规划问题.自由落体的猫在空中转体运动由于角速度不可积,姿态运动方程呈现为非完整形式.当系统角动量为0时,导出由两个对称刚体组成的自由下落猫的非完整姿态运动方程.利用该非完整方程系统的控制问题可转化为无漂移系统的非完整运动规划问题.基于Ritz近似理论,给出自由落体猫姿态运动规划的Gauss-Newton算法.最后对自由落体猫作了数值仿真实验,仿真结果验证了该算法的有效性. 相似文献
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The National Council of Teachers of Mathematics has set ambitious goals for the teaching and learning of mathematics that include preparing students for both the workplace and higher education. While this suggests that it is important for students to develop strong mathematical competencies by the end of high school, there is evidence to indicate that overall this is not the case. Both national and international studies corroborate the concern that, on the whole, US 12th grade students do not demonstrate mathematical proficiency, suggesting that students making the transition from high school to college mathematics may not be ready for its rigors. In order to investigate mathematical readiness of entering college students, this study surveyed mathematics faculty. Specifically, faculty members were asked their perceptions of average entering students' readiness related to relevant mathematical skills and concepts, and the importance of the same skills and concepts as foundations for college mathematics. Results demonstrated that the faculty perceived that average freshman students are generally not mathematically prepared; further, the skills and concepts rated as highly important — namely, algebraic skills and reasoning and generalization — were among those rated the lowest in terms of student competencies. 相似文献