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111.
水面舰艇鱼雷防御系统综述   总被引:5,自引:0,他引:5  
综述了国外水面舰艇鱼雷防御系统的现状,分析了水面舰艇鱼雷防御系统的关键技术和发展趋势,对发展我国水面舰艇鱼雷防御系统具有一定的积极作用。  相似文献   
112.
国有企业“模拟股份制”是以资产增值为目标,以资产经营者的市场竞争方式产生为手段,将企业制度创新与国有资产经营管理相结合的一种资产经营体制。  相似文献   
113.
In this work, a full-state feedback controller is designed to prevent the oscillatory instability or snaking behaviour of an articulated steer vehicle. To design the controller, first, a linearized model of the vehicle is developed and analyzed to identify the most important uncertain tire parameters with regard to the snaking mode. By using this linearized model, the equations of motion are represented in the form of a polytopic system, which depends affinely on the most important uncertain tire parameters. Then, by solving some linear matrix inequalities, both the Lyapunov and state feedback matrices for the robust stabilization of the vehicle are found. The performance of the resulting controller is evaluated by conducting several simulations based on the linearized model. To verify the results from the linearized model analysis, some simulations are also done by a virtual prototype of the vehicle in ADAMS. The results based on the linearized model are reasonably consistent with those from the simulations in ADAMS. They show that the controller can effectively stabilize the vehicle during the snaking mode in different driving conditions.  相似文献   
114.
Parking demand is a significant land-use problem in campus planning. The parking policies of universities and large corporations with facilities located in small urban areas shape the character of their campuses. These facilities will benefit from a simplified methodology to study the effects of parking availability on transportation mode mix and impacts on recruitment and staffing policies. This paper, based on a case study of North Dakota State University in the United States, introduces an analytical framework to provide planners with insights about how parking supply and demand affects campus transportation mode choice. The methodology relies only on aggregate mode choice data for the special generator zone and the average aggregate volume/capacity ratio projections for all external routes that access the zone. This reduced data requirement significantly lowers analysis cost and obviates the need for specialized modelling software and spatial network analysis tools. Results illustrate that the framework is effective for analysing mode choice changes under different scenarios of parking supply and population growth.  相似文献   
115.
作为传统的中华帝国,清政府一直保持着与东亚诸国的朝贡关系.但是嘉庆年间确立了新的朝贡体制,将之前的朝贡国家与之后开始贸易交往的国家区分开.东亚的朝鲜和琉球一直都是中国的朝贡国.由于日本施行闭关锁国政策,所以不是中国的朝贡国,但清朝嘉庆年间,日本被中国视作朝贡国中的贸易互市国加以对待.  相似文献   
116.
方便旗问题是个世界性难题,我国政府一直致力于解决中资船舶移籍这一问题.通过分析方便旗及相关船舶登记制度历史背景的基础上,探讨洋山保税船舶登记制度建立的意义和存在的问题,并结合中国(上海)自由贸易区总体方案,提出了未来完善洋山保税船舶登记制度的相关对策.  相似文献   
117.
This research proposes a short-term highway traffic state prediction method based on a structural state space model, with the intention to provide a robust approach for obtaining accurate forecasts of traffic state under both recurring and non-recurring conditions. True traffic state is decomposed to three components, namely, regular traffic pattern, structural deviation, and random fluctuation. Particularly, the structural deviation term reflects the change of true traffic state from regular (historical) pattern, due to unexpected capacity reduction and/or demand variations. A polynomial trend is adopted to describe the temporal evolution of structural deviations across different time intervals. We derive an analytical form of structural deviations in a single bottleneck case based on cumulative flow count diagrams. The proposed model is incorporated in a Kalman filtering-based algorithmic framework, together with an adaptive scheme for determining the variances of random errors. A set of numerical experiments was conducted on two test beds in the northern Taiwan highway network. Experimental results show that the proposed approach is particularly superior to an ordinary Kalman filtering method presented in the literature under non-recurring conditions, highlighting the advantage of combining both the polynomial trend model and historical pattern into the proposed short-term traffic state prediction approach.  相似文献   
118.
针对道岔状态不良,通过建立涵盖道岔全生命周期的故障树模型,计算最小割集、顶事件概率和基本事件的临界重要度,对道岔状态不良进行定量风险分析.围绕风险控制的消除、预防、减轻后果、事故应急4个方面,研究提出8项针对性的风险控制措施,并建立控制措施有效性评价矩阵,来评价措施有效性.结果表明,道岔状态不良属于风险程度较高的危害事...  相似文献   
119.
经济宪法学研究的尝试:分税制决定权的宪法解释   总被引:1,自引:0,他引:1  
本文运用法律优先和法律保留原则,通过对宪法有关条款的解释分析,认为在现行宪政框架下,国务院不具有作出"分税制决定"的职权,分税制决定权属于全国人民代表大会,全国人民代表大会对国务院的"分税制决定"予以事后确认并不合适;在全国人民代表大会及其常务委员会作出分税制决议的情况下,地方政府对于分税制问题具有法律上的作用空间;国务院作出"分税制决定"和全国人民代表大会予以追认,说明了我国当时的依法治国现实状况,以及在作出改革决策前进行合宪性和合法性论证的必要性。本文所运用的研究方法对分析其它同类样本,并逐步形成经济宪法学,具有一定的理论意义。  相似文献   
120.
沈瑜 《中国海事》2022,(2):61-63
随着《压载水公约》的生效,如何更好地实施公约要求成了港口国关注的重点。港口国监督(PSC)在促进港口国实施公约中发挥着重要作用[1]。然而,随着PSC的深入,一些潜在的问题也值得关注。总结了目前PSC执行《压载水公约》过程中存在的风险与不确定性,并提出了相应的解决建议。  相似文献   
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