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排序方式: 共有148条查询结果,搜索用时 15 毫秒
121.
介绍了用于舰船蒸汽动力装置热线图优化的可视化程序设计与研究.阐述了软件的主要功能、开发环境、数据库设计以及关键技术问题的解决途径.程序能通过调整各种设计参数来得到良好的热线图. 相似文献
122.
针-板电极电晕辐射仿真研究 总被引:1,自引:0,他引:1
电晕放电是静电放电的一种特殊形式。在分析电晕放电特性的基础上,对针-板电极系统高压电晕辐射场方向特性进行了仿真研究。通过实验与仿真得出:针-板电极系统高压电晕辐射场频谱范围大约为10~200MHz,能量主要集中在80 MHz以下。80 MHz以下辐射场方向图与偶极子天线的辐射方向图相似,低于100 MHz的辐射主要在针电极一侧,而高于100 MHz以上的辐射场方向图极为复杂,其主要辐射在板电极的后方。电晕放电辐射场的空间分布与放电电压、电极的形状以及电晕的发展过程等因素有关,对于电晕放电的不同发展阶段,其辐射场的频域范围也不同。 相似文献
123.
Antti Seppo 《Defense & Security Analysis》2019,35(4):384-405
ABSTRACTGerman security and defence policy has undergone substantial transformation. This transformation requires an unprecedented level of political leadership, suggesting that Germany needs to solve the dilemma of how to supply leadership to increasingly demanding partners. What are the conditions under which German leadership can unfold in security and defence policy? To what degree do German role-conceptions of international agency and role-expectations of German leadership coincide? What kind of leadership outputs are produced? This study offers a comprehensive analysis of German security and defence policy in terms of supply (role conceptions) and demand (role expectations). We outline three leadership role conceptions present in the German strategic debate, which we then assess in the context of the Wendtian theory of cultures of anarchy. We then analyse Berlin's leadership in terms of outputs via the case study on Anchor Army and the Framework Nations Concept. We conclude that while Germany has tried to match leadership role expectations both rhetorically and in action, Berlin's leadership inputs have so far been insufficient. This has led to an imbalance in terms of role conceptions and expectations hampering effective German leadership in security and defence policy. 相似文献
124.
王凯 《装甲兵工程学院学报》1998,(3)
概述美国陆军现阶段实施的2010年发展战略规划,分析阐明美军制定和实行该规划理论基础和指导方针,陆军结构调整与改革的思路和实施的内容,在军队建设上如何充分发挥科学技术优势等. 相似文献
125.
In rewards-based crowdfunding, entrepreneurs solicit donations from a large number of individual contributors. If total donations exceed a prespecified funding target, the entrepreneur distributes nonmonetary rewards to contributors; otherwise, their donations are refunded. We study how to design such campaigns when contributors choose not just whether to contribute, but also when to contribute. We show that strategic contribution behavior—when contributors intentionally delay until campaign success is likely—can arise from the combination of nonrefundable (potentially very small) hassle costs and the risk of campaign failure, and can explain pledging patterns commonly observed in crowdfunding. Furthermore, such delays do not hurt the entrepreneur if contributors are perfectly rational, but they do if contributors are distracted, that is, if they might fail to return to the campaign after an intentional delay. To mitigate this, we find that an entrepreneur can use a simple menu of rewards with a fixed number of units sold at a low price, and an unlimited number sold at a higher price; this segments contributors over time based on the information they observe upon arrival. We show that, despite its simplicity, such a menu performs well compared to a theoretically optimal menu consisting of an infinite number of different rewards and price levels under many conditions. 相似文献
126.
损伤定位流程制定的合理与否是衡量一个评估员水平高低的重要指标之一。对损伤定位流程的评价涉及到所用时间、工具、操作的难度等指标都可以用其复杂性来表示,目前鲜有关于损伤定位流程评价的研究,因此提出战场损伤定位流程的复杂性,并借鉴软件工程领域的程序复杂性量化方法——图熵法对其进行量化。经过数据验证,复杂性与评估时间之间存在较好的拟合关系,并用实例说明了模型的应用效果。 相似文献
127.
王彩霞 《中国人民武装警察部队学院学报》2010,26(9):49-52
对现阶段公安现役部队全面预算管理现状和面临的问题进行了分析,从确定部队战略目标,党委重视和全员参与,构建全面预算管理组织结构及制度体系,全面预算的编制、控制、调整及考评等几个方面提出了有效实施全面预算管理的思路和具体措施。 相似文献
128.
Lezhen Wu;Dingwei Gu;Zhiyong Yao;Wen Zhou; 《海军后勤学研究》2024,71(2):174-188
It is well-established in the literature that a horizontal merger in a supply chain is profitable (or beneficial to firms at another tier) if the merger synergy exceeds some threshold referred to as the profitable (or beneficial) threshold. Our paper goes one step further by finding that the profitable threshold is always lower than the beneficial threshold, which implies that a firm may have an incentive to prevent a horizontal merger between its suppliers or customers, but never wants to precipitate one. Moreover, we propose a strategy to achieve the preventive goal—a firm can develop an instrumental merger option with another rival firm, which can help prevent the target merger in one of two ways. First, if the synergy of the instrumental merger is high relative to the synergy of the target merger, the firm can carry out the instrumental merger—even an unprofitable one—preemptively to make the target merger unprofitable. Second, if the synergy of the target merger is not too high and the synergy of the instrumental merger is moderate, that is, the instrumental merger is profitable and will inflict severe harm on the firms in the target merger, the firm can reserve the instrumental merger option as a deterrent and the profitable target merger is deterred. An interesting implication of the deterrent role of the instrumental merger option is that when the firm has two candidate merger partners, it may choose the partner with a lower synergy for the deterrence purpose. 相似文献
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