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91.
高校的教育改革应当以课程改革为主导。公安现役高等教育的改革,涉及面广,内容复杂,但就其核心因素分析,课程在其中占据重要的地位。公安现役本科院校基础课程具有基础性、大面积性、核心性和经典性等特点,因此,在公安现役本科院校基础课程体系中具有举足轻重的地位。其改革应当遵循一定的原则予以实施。 相似文献
92.
We present a tactical decision model for order acceptance and capacity planning that maximizes the expected profits from accepted orders, allowing for aggregate regular as well as nonregular capacity. The stream of incoming order arrivals is the main source of uncertainty in dynamic order acceptance and the company only has forecasts of the main properties of the future incoming projects. Project proposals arrive sequentially with deterministic interarrival times and a decision on order acceptance and capacity planning needs to be made each time a proposal arrives and its project characteristics are revealed. We apply stochastic dynamic programming to determine a profit threshold for the accept/reject decision as well as to deterministically allocate a single bottleneck resource to the accepted projects, both with an eye on maximizing the expected revenues within the problem horizon. We derive a number of managerial insights based on an analysis of the influence of project and environmental characteristics on optimal project selection and aggregate capacity usage. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
93.
94.
大学生创新能力的培养与课程教学 总被引:1,自引:1,他引:0
杨醒民 《装甲兵工程学院学报》1999,(4)
从创新精神、创造性思维、创新实践能力3个方面论述了创新能力,并着重论述了在课程教学中如何培养学生的这一能力。 相似文献
95.
章向明 《海军工程大学学报》1994,(2)
本文用光弹性实验方法验证了有限元法对42—160柴油机离合器换向拨叉优化设计的结果。实验证明,有限元优化设计是正确、可靠的,效果是非常好的。 相似文献
96.
本文提出了一种具有广泛应用前景的程序设计方法——表格驱动(Formdriven)程序设计方法(以下简称表格驱动法)。文中首先描述了表格驱动法的基本思想、解的结构;分析了这种方法的特点与适用性;剖析了基于表格驱动法的办公自动化软件ALL-IN-1的设计思想,并指出表格驱动法特别适合于设计软件开发工具。 相似文献
97.
利用非线性规划方法研究了航天器的有限推力最优交会问题。这种方法利用了近年来发展起来的直接优化技术,用分段多项式来表示整个轨道的状态和控制向量,将最优控制问题转化为非线性规划问题。在应用这种方法时,先将整个轨道分为若干推力段和无推力段,然后利用配置方法产生推力段的约束段,利用状态转移矩阵来产生无推力段的约束。最后,对共面轨道情况下的交会进行了数值仿真,验证了方法的有效性和鲁棒性。 相似文献
98.
Sanjay Mehrotra Hamed Rahimian Masoud Barah Fengqiao Luo Karolina Schantz 《海军后勤学研究》2020,67(5):303-320
We present a stochastic optimization model for allocating and sharing a critical resource in the case of a pandemic. The demand for different entities peaks at different times, and an initial inventory for a central agency are to be allocated. The entities (states) may share the critical resource with a different state under a risk-averse condition. The model is applied to study the allocation of ventilator inventory in the COVID-19 pandemic by FEMA to different U.S. states. Findings suggest that if less than 60% of the ventilator inventory is available for non-COVID-19 patients, FEMA's stockpile of 20 000 ventilators (as of March 23, 2020) would be nearly adequate to meet the projected needs in slightly above average demand scenarios. However, when more than 75% of the available ventilator inventory must be reserved for non-COVID-19 patients, various degrees of shortfall are expected. In a severe case, where the demand is concentrated in the top-most quartile of the forecast confidence interval and states are not willing to share their stockpile of ventilators, the total shortfall over the planning horizon (until May 31, 2020) is about 232 000 ventilator days, with a peak shortfall of 17 200 ventilators on April 19, 2020. Results are also reported for a worst-case where the demand is at the upper limit of the 95% confidence interval. An important finding of this study is that a central agency (FEMA) can act as a coordinator for sharing critical resources that are in short supply over time to add efficiency in the system. Moreover, through properly managing risk-aversion of different entities (states) additional efficiency can be gained. An additional implication is that ramping up production early in the planning cycle allows to reduce shortfall significantly. An optimal timing of this production ramp-up consideration can be based on a cost-benefit analysis. 相似文献
99.
针对当前具有吞吐量和时延约束的软件无线电波形部署决策算法在内存开销方面考虑的不足,提出一个更为通用的波形部署决策系统模型,将波形的处理开销、内存开销和通信带宽开销都纳入到波形部署决策过程中,并设计了一种基于动态规划的波形部署决策算法以最小化波形对平台各种计算资源的占用总和。仿真结果表明,内存对波形部署决策具有重要影响,与未考虑内存开销的解决方案相比,平台支持的平均最大波形数目和平均处理资源利用率均下降40%左右。 相似文献
100.
This article provides an efficient heuristic based on decomposition for the twin robots scheduling problem (TRSP). TRSP concerns two moving robots executing storage and retrieval requests in parallel along a shared pathway. The depots are located at both ends of the line and a dedicated robot is assigned to each of them. While moving goods between their respective depots and some storage locations on the line, noncrossing constraints among robots need to be considered. Our heuristic uses a dynamic programming framework to determine the schedule of one robot while keeping the other one's fixed. It finds near‐optimal solutions even for large problem instances with hundreds of jobs in a short time span. © 2014 Wiley Periodicals, Inc. 62:16–22, 2015 相似文献