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901.
随着序列情形费用型投资模型和折扣投资模型的解决,本文对其进行连续推广,并给出一个明确的停止规则。 相似文献
902.
DCT+运动估计与补偿方法是实用的视频编码方法。目前包括甚低速视频编码标准H.263在内的多种视频标准均采用这种方法。考虑到视觉对于边缘信息的敏感性,我们根据边缘特性对编码块进行分类量化,使得边缘附近的量化噪声具有边缘相似性,从而最优地保留对于视觉敏感的DCT系数,在保证编码效率的同时较大地提高了重建图像质量 相似文献
903.
Whether military spending is capable of promoting social welfare is currently a controversial issue. The aim of this paper is to investigate how military spending affects the input and output of social welfare (i.e. social welfare expenditures and social welfare index). A panel cointegration analysis and an impulse response function are conducted with multi-country panel data, over two time periods, 1998–2011 and 1993–2007. In addition, to extend a comparative analysis over different economies, BRICS (i.e. Brazil, Russia, India, China, South Africa) and G7 (i.e. the US, Japan, Germany, the UK, France, Italy, Canada) countries are selected as representatives of emerging economies and developed countries, respectively. The empirical results show that military spending enhances social welfare expenditures in developed countries, while the effect is ambiguous in emerging economies. Also, military spending is capable of promoting the social welfare index based on the FMOLS estimation. The comparative analyses indicate that unlike in the G7, the effect of the growth of military spending on the growth of social welfare expenditures is negative and shorter in the BRICS. 相似文献
904.
A bicriterion approach to common flow allowances due window assignment and scheduling with controllable processing times 下载免费PDF全文
We investigate a single‐machine scheduling problem for which both the job processing times and due windows are decision variables to be determined by the decision maker. The job processing times are controllable as a linear or convex function of the amount of a common continuously divisible resource allocated to the jobs, where the resource allocated to the jobs can be used in discrete or continuous quantities. We use the common flow allowances due window assignment method to assign due windows to the jobs. We consider two performance criteria: (i) the total weighted number of early and tardy jobs plus the weighted due window assignment cost, and (ii) the resource consumption cost. For each resource consumption function, the objective is to minimize the first criterion, while keeping the value of the second criterion no greater than a given limit. We analyze the computational complexity, devise pseudo‐polynomial dynamic programming solution algorithms, and provide fully polynomial‐time approximation schemes and an enhanced volume algorithm to find high‐quality solutions quickly for the considered problems. We conduct extensive numerical studies to assess the performance of the algorithms. The computational results show that the proposed algorithms are very efficient in finding optimal or near‐optimal solutions. © 2017 Wiley Periodicals, Inc. Naval Research Logistics, 64: 41–63, 2017 相似文献
905.
Strategic spectrum occupancy for secondary users in cognitive radio networks with retrials 下载免费PDF全文
This article investigates joining strategies and admission control policy for secondary users (SUs) with retrial behavior in a cognitive radio (CR) system where a single primary user (PU) coexists with multiple SUs. Under a certain reward‐cost structure, SUs opportunistically access the PU band when it is not occupied by the PU. If the band is available upon arrival, an SU decides with a probability either to use the band immediately or to balk the system. If the band is occupied, the SU must decide whether to enter the system as a retrial customer or to leave the system. Once the PU requests for service, the service of SU being served, if any, will be interrupted, and the interrupted SU leaves the band and retries for service after a random amount of time. In this article, we study the equilibrium behavior of non‐cooperative SUs who want to maximize their benefit in a selfish, distributed manner with delay‐sensitive utility function. The socially optimal strategies of SUs are also derived. To utilize the PU band more efficiently and rationally, an admission control policy is proposed to regulate SUs who enter the system in order to eliminate the gap between the individually and socially optimal strategies. 相似文献
906.
王文利 《军队政工理论研究》2009,10(2)
随着诸军种联合作战的规模和频率不断增加,为改进联合作战能力,美军对联合作战指挥结构进行了改革,出台了联合军官管理制度,对联合军官的选拔、教育和晋升等作出了具体的规定. 相似文献
907.
国民党蒋介石集团退踞台湾之后的威权时代,在强烈危机意识的作用下,全面改造党组织和军队,党军关系呈现新的局面。国民党从思想和组织两方面对军队进行的有效控制,不仅确保了蒋家王朝在台湾统治的延续,也使军队的地位和影响力得到前所未有的提高,震慑了各种异己力量包括“台独”势力在岛内的恶性生长。 相似文献
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910.
战争与和平对立统一、相互交织,构成了人类生活的主题,因其与社会进步和人类发展休戚相关,成为古今中外人们关注的焦点.从某种程度上说,人类的历史就是一部战争史,战争因对社会发展的巨大推动作用和给人类带来的深重浩劫而成为一体两面的价值体.战争的暴烈使人们渴望和平,并以不同形式展开了对和平的追求.在人类历史上,和平要比战争成熟得晚.在和平与发展的历史条件下,维护和平、制止战争是全人类共同的责任. 相似文献