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961.
公本文从社会主义核心价值体系认同、执政党认同、理论认同、民族认同四个维度对大学生主流文化认同进行调查分析,结果显示,大学生主流文化认同总体是积极向上的,但也存在不平衡性和差异,主流文化认同面临严峻挑战。加强对大学生群体主流文化认同教育,引导大学生树立正确的国家观、民族观、文化观,对边疆多民族地区未来发展和国家安全十分重要。  相似文献   
962.
党的十八大和十八届三中全会提出"健全鼓励高校毕业生到基层工作的服务保障机制"的工作任务,基层就业成为大学生就业的重要渠道之一。为深入了解兵团高校大学生赴到兵团基层单位就业的状况,以石河子大学为个案,通过分析和梳理石河子大学毕业生到兵团基层就业情况及存在问题,尝试构建高校毕业生到兵团基层单位就业新机制,以期更好的为兵团基层发展提供智力支持和人才保障。  相似文献   
963.
对成像雷达的脉冲分段排序转发干扰   总被引:1,自引:1,他引:0       下载免费PDF全文
多假目标图像欺骗是目前宽带雷达干扰的难点。针对宽带雷达中常用的线性调频(Linear Frequency Modulated,LFM)信号,提出一种脉冲分段排序转发干扰方法。结合散射波信号模型,推导了合成干扰信号二维成像输出形式,讨论了假目标图像个数、分辨率与分段数以及转发次序之间的关系,并进行了仿真实验。结果表明该干扰方法可较便捷地产生多个沿距离向分布的假目标图像。结果对于成像雷达图像欺骗干扰具有理论指导意义。  相似文献   
964.
We consider a capacitated inventory model with flexible delivery upgrades, in which the seller allocates its on‐hand inventory to price‐ and delivery‐time‐sensitive customers. The seller has two decisions: inventory commitment and replenishment. The former addresses how the on‐hand inventories are allocated between the two classes of customers within an inventory cycle. The latter addresses how the inventory is replenished between inventory cycles. We develop optimal inventory allocation, upgrade, and replenishment policies and demonstrate that the optimal policy can be characterized by a set of switching curves. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 418–426, 2014  相似文献   
965.
We study a supply chain in which an original equipment manufacturer (OEM) and a contract manufacturer (CM) compete in the finished goods market. The OEM can decide whether to outsource the intermediate good, a critical component for producing the finished good, from the CM or make in‐house production. Technology transition improves the CM's production efficiency, and it can take two different forms: a direct technology transfer from the OEM to the CM or technology spillovers through outsourcing from the OEM to the CM. We document the possibility of strategic outsourcing, that is, the CM supplies the intermediate good to the OEM when she is less efficient than the OEM's in‐house production. We find that technology spillovers can strengthen the incentive for strategic outsourcing. Furthermore, compared with direct technology transfers, outsourcing coupled with technology spillovers may generate more technology transition. Outsourcing is a particularly appropriate channel for implicit collusion when the OEM is not very efficient with the production of the intermediate good. Our results suggest that ex post competition on the finished goods can create room for ex ante collaboration and provide some implications on the OEM's outsourcing strategies when facing a competitive CM.© 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 501–514, 2014  相似文献   
966.
We consider the problem of assessing the value of demand sharing in a multistage supply chain in which the retailer observes stationary autoregressive moving average demand with Gaussian white noise (shocks). Similar to previous research, we assume each supply chain player constructs its best linear forecast of the leadtime demand and uses it to determine the order quantity via a periodic review myopic order‐up‐to policy. We demonstrate how a typical supply chain player can determine the extent of its available information in the presence of demand sharing by studying the properties of the moving average polynomials of adjacent supply chain players. The retailer's demand is driven by the random shocks appearing in the autoregressive moving average representation for its demand. Under the assumptions we will make in this article, to the retailer, knowing the shock information is equivalent to knowing the demand process (assuming that the model parameters are also known). Thus (in the event of sharing) the retailer's demand sequence and shock sequence would contain the same information to the retailer's supplier. We will show that, once we consider the dynamics of demand propagation further up the chain, it may be that a player's demand and shock sequences will contain different levels of information for an upstream player. Hence, we study how a player can determine its available information under demand sharing, and use this information to forecast leadtime demand. We characterize the value of demand sharing for a typical supply chain player. Furthermore, we show conditions under which (i) it is equivalent to no sharing, (ii) it is equivalent to full information shock sharing, and (iii) it is intermediate in value to the two previously described arrangements. Although it follows from existing literature that demand sharing is equivalent to full information shock sharing between a retailer and supplier, we demonstrate and characterize when this result does not generalize to upstream supply chain players. We then show that demand propagates through a supply chain where any player may share nothing, its demand, or its full information shocks (FIS) with an adjacent upstream player as quasi‐ARMA in—quasi‐ARMA out. We also provide a convenient form for the propagation of demand in a supply chain that will lend itself to future research applications. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 515–531, 2014  相似文献   
967.
In this article, we address a stochastic generalized assignment machine scheduling problem in which the processing times of jobs are assumed to be random variables. We develop a branch‐and‐price (B&P) approach for solving this problem wherein the pricing problem is separable with respect to each machine, and has the structure of a multidimensional knapsack problem. In addition, we explore two other extensions of this method—one that utilizes a dual‐stabilization technique and another that incorporates an advanced‐start procedure to obtain an initial feasible solution. We compare the performance of these methods with that of the branch‐and‐cut (B&C) method within CPLEX. Our results show that all B&P‐based approaches perform better than the B&C method, with the best performance obtained for the B&P procedure that includes both the extensions aforementioned. We also utilize a Monte Carlo method within the B&P scheme, which affords the use of a small subset of scenarios at a time to estimate the “true” optimal objective function value. Our experimental investigation reveals that this approach readily yields solutions lying within 5% of optimality, while providing more than a 10‐fold savings in CPU times in comparison with the best of the other proposed B&P procedures. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 131–143, 2014  相似文献   
968.
Abstract

This article draws upon previously unavailable document materials to question views pointing to a degree of stagnation in Japanese maritime thinking. It similarly reviews claims about trends to compensate the decline of national military power with the build-up of projection capabilities. The article’s main argument is that Japanese seapower is not declining. The Japanese Navy is evolving to combine enhanced capabilities to retain sea control in the Sea of Japan and the East China Sea with extended operational reach and flexibility, including an expeditionary component to meet alliance and diplomatic commitments in East Asia and beyond its confines.  相似文献   
969.
舰艇编队防空过程建模及分析   总被引:1,自引:0,他引:1       下载免费PDF全文
防空作战是大型水面舰艇编队的主要作战样式之一。运用PEPA(性能评价过程代数)方法对舰艇编队防空作战全过程进行有效建模,形式化描述了预警探测、情报传递、命令下达、防空拦截等作战主要过程。建立的PEPA模型具有层次化结构,考虑了要素间相互协作,体现了编队防空作战分布、并发的特点。通过对建立的PEPA模型进行性能指标选择和稳定状态分析,得到了不同因素对编队能力发挥的影响情况,获得了防空作战的基本要素组成,从而提供了一种解决舰艇编队问题的新方法。  相似文献   
970.
针对分布式星群网络业务通信QoS不高的问题,提出了一种基于流量均衡和跨层技术的分布式星群网络路由算法(TACA)。该算法首先通过跨层技术将物理层、MAC层的相关信息搜集起来,作为判断链路负载状况的依据;然后对不同类型的业务进行分类,根据链路负载状况和业务QoS级别选择不同的路由层次,从而均衡流量以提高QoS。仿真表明,该路由算法在一定程度上降低了星群的呼叫阻塞率和切换阻塞率,平衡了网络的负载,提高了网络吞吐量。  相似文献   
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