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51.
基于BP神经网络的装备器材需求预测模型   总被引:3,自引:0,他引:3  
准确预测装备器材的需求数量,是装备器材保障工作的重要内容和装备器材计划管理的前提。采用BP神经网络算法,通过对装备器材历史消耗数据进行处理,建立了装备器材需求预测模型,并结合实例,对模型进行了探讨和验证。  相似文献   
52.
燃烧室压力对潜入式喷管喉衬热应力的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
为了研究燃烧室压力对固体火箭发动机潜入式喷管热应力影响规律的问题,采用商业流体软件,基于压力求解器,求解了喷管纯气相的流场,确定了燃气温度、压力、壁面对流换热系数;采用有限元软件,依据流场计算的非均布壁面压力与非均布对流换热,求解了燃烧室压力为6 MPa下的潜入式喷管热结构问题;通过地面点火试验验证了仿真模型与数值方法...  相似文献   
53.
对战备物资进行分类是选择储备模式的基础和重要前提。把战备物资分类问题抽象为战备物资的军事性和经济性评价问题,设计了物资分类评价指标体系,并对部分指标进行了说明;利用层次分析法确定各指标的权重,运用专家打分法完成指标打分,并对专家打分程序进行优化,增强战备物资分类的可操作性,由军事性和经济性两方面的得分确定战备物资所属类别;最后通过算例证明了分类方法的有效性。  相似文献   
54.
针对基层消防部门火灾调查人员在调查中造成物证损坏所存在的问题,通过对火灾调查中物证损坏原因的探讨,分析研究物证在收集、提取、保管、检测鉴定及其它过程中造成损坏的原因,并提出减少或避免这些损坏应该采取的具体措施和方法。使火调人员在火灾事故调查过程中充分考虑到物证损坏对火灾调查工作的影响,对于提高火灾调查人员的办案能力,避免调查中物证损坏具有一定的指导意义。  相似文献   
55.
本文主要论述了新疆少数民族双语教学中汉语教学的重要性及存在的困境,并对如何在教学中提高少数民族学生的汉语表达能力进行了探讨,并提出了几点建议:克服少数民族学生开口表达汉语的心理障碍;创设汉语表达语境让学生感知汉语交际情景;运用直观教学手段强化民族学生汉语表达的培养;教学中运用多种方法训练和培养学生用汉语的思维习惯。  相似文献   
56.
现行装备器材供应存在着供应渠道过长、不能快速响应等问题,为此通过对装备器材供应链进行集成化体系结构模型设计与构建,探讨了装备器材供应链的重构策略,分别从信息流模式重构、业务流程重构和物流体系重构等3个主要方面对装备器材供应链重构策略进行了分析与探讨,以实现装备器材供应链的快速响应.  相似文献   
57.
Nuclear weapon states historically have attached great secrecy to their nuclear weapon and fissile material production programs and stockpiles, despite warnings that this would fuel fears, handicap informed debate and decision making, and drive arms races. As evidenced by the “Action Plan on Nuclear Disarmament” agreed upon at the 2010 Treaty on the Non-Proliferation of Nuclear Weapons (NPT) Review Conference, however, the international community now sees greater transparency about nuclear weapon and fissile material stocks as necessary for enabling and monitoring progress toward nuclear disarmament. To support this effort, the International Panel on Fissile Materials has proposed a step-by-step program for weapon states to declare their inventories, production histories, and disposition of nuclear warheads and fissile materials, and to set up joint projects to develop methods for verifying these declarations. This openness initiative is described here, and could be adopted at the 2015 NPT Review Conference, laying a basis for negotiating verifiable deep reductions in nuclear arsenals and their eventual elimination.  相似文献   
58.
The Egyptian military's unconstitutional removal of President Mohamed Morsi has reignited a debate regarding the theory of the ‘democratic coup’. Though coups are almost invariably condemned, many political observers and a few scholars have recently argued that coups can act as catalysts for democratisation. This paper empirically assesses the democratic coup hypothesis for Africa. Multivariate analyses from 1952 to 2012 suggest that coups statistically improve a country's democratisation prospects. Extensions of the model show that coups appear to be likely precursors for democratisation in staunchly authoritarian regimes and have become less likely to end democracy over time, and that their positive influence has strengthened since the end of the Cold War. As of 2012, countries that have experienced a recent coup are expected to be four times more likely to witness a democratic transition than those that have remained coup-free.  相似文献   
59.
So far, economic analyses of NATO enlargement have been restricted to aspects of regional security while political analyses focused on indirect peace‐building effects on democracy in the first place. Our panel regressions for 25 post‐communist countries for the period from 1996 to 2008 reveal that direct incentives provided by NATO pre‐accession are important for broad‐based institutional development. Results are even more robust than for variables measuring EU pre‐accession or NATO membership effects. This supports the argument that NATO can act as a transformative power and should strengthen its political agenda.  相似文献   
60.
The Cold War at sea expanded in many realms, including the frigid and treacherous waters of the Arctic Ocean. The US Navy pioneered these efforts with the visit of USS Nautilus to the North Pole in 1958. During the latter stages of the Cold War, however, Soviet naval strategists began to conceptualize the polar ice cap as a strategic asset for cloaking the operations of its nuclear missile submarines. As under-ice operations afforded the Soviet submarine fleet advantages of stealth, proximity to target and tighter lines of communications, both navies were forced to try to develop tactics for combat under these extremely complex and arduous conditions.  相似文献   
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