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61.
基于LDO稳压器在电磁干扰(EMI)下产生直流偏移失效的机理分析,展开敏感度建模与仿真方法研究。使用一款实验芯片,创新地引入片上电压传感器,用于测试EMI在LDO稳压器内部的传播特性。在敏感度建模中,建立等效电路模型,通过直流功能测试,Z参数阻抗特性测试验证模型的正确性,将该模型用于LDO稳压器的敏感度预测。在敏感度仿真过程中,通过分析关键子电路和不断增加寄生元件,仿真不同寄生因素对敏感度影响的权重。将仿真结果与传导直接注入法(DPI)片上测试结果对比,仿真结果与DPI测试在频域1MHz至1GHz匹配。 相似文献
62.
63.
Digby Waller 《Defence and Peace Economics》2013,24(2):225-241
Data limitations arising from non‐transparency in military expenditure reporting impose significant constraints on economists studying country and comparative developments in this field. This article focuses on the case of China. It reviews the recent literature on China's military expenditure, examines the variance in published estimates, and identifies three factors which help explain the variance: budgetary falsification; non‐budgeted PLA revenue; and the US dollar purchasing‐power parity of the yuan. Conclusions emphasize important policy implications of such variance and suggest a more active role for defence economists in a field of research generating considerable attention from international relations scholars. 相似文献
64.
针对反导导弹战斗部的性能特点,以灰色关联理论为基础,采用灰色加权关联度分析进行综合评判,建立了反导导弹战斗部作战效能评估模型.最后通过算例,验证了该模型的完整性,最终为决策者做出合理的作战决策提供了理论参考. 相似文献
65.
Gerald Felix Warburg 《The Nonproliferation Review》2013,20(3):451-471
On October 1, 2008, Congress enacted a proposal that originated with President George W. Bush in 2005 to approve an unprecedented nuclear trade pact with India by removing a central pillar of US nonproliferation policy. Despite the numerous political challenges confronting the Bush administration, the initiative won strong bipartisan support, including votes from Democratic Senators Joseph Biden, Hillary Clinton, and Barack Obama. The four-year struggle to pass the controversial US-India nuclear trade agreement offers an exceptionally valuable case study. It demonstrates a classic tradeoff between the pursuit of broad multilateral goals such as nuclear nonproliferation and advancement of a specific bilateral relationship. It reveals enduring fault lines in executive branch relations with Congress. It vividly portrays challenges confronting proponents of a strong nonproliferation regime. This article is based on an analysis of the negotiating record and congressional deliberations, including interviews with key participants. It assesses the lessons learned and focuses on three principal questions: how did the agreement seek to advance US national security interests?; what were the essential elements of the prolonged state-of-the-art lobbying campaign to win approval from skeptics in Congress?; and what are the agreement's actual benefits—and costs—to future US nonproliferation efforts? 相似文献
66.
Leonard Weiss 《The Nonproliferation Review》2013,20(2):269-284
The phenomenon of global warming has led to a revival of the prospects for increased nuclear energy production worldwide, yet such increased production carries with it the increased risk of proliferation. To mitigate this risk, various multinational arrangements have been proposed to provide reliable supply of nuclear fuel while at the same time discouraging the construction of national plants for nuclear enrichment and reprocessing. This article provides a brief history of some of these proposals and concludes that the likelihood of success for such schemes as effective tools for nonproliferation is not high at this time. A proposal from the World Council on Renewable Energy to expand the understanding of supplier obligations under Article IV of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) to include the development of non-nuclear energy technologies for NPT parties in good standing is potentially a much better nonproliferation tool. Such an approach tracks the ideas contained in Title V of the Nuclear Non-Proliferation Act of 1978, which has recently received revived congressional interest. 相似文献
67.
相机内置预处理环节中的白平衡、色度空间转换是数码成像过程中的重要环节,sRGB和Adobe RGB是数码相机2种常用的色空间.为进一步研究色空间对HDRI亮度测量方法的影响,在荧光灯照明的实验室,分别利用sRGB和Adobe RGB色空间对色板成像,测量该亮度测量方法中各色板的标定因数,计算各色板标定因数的相对不确定度.实验结果表明:2种不同色空间获得的标定因数不同,且Adobe RGB色空间标定因数相对不确定度的平均值小于sRGB色空间的;色空间改变后,标定因数需要重新进行标定,且优先选用色域较宽的Adobe RGB色空间. 相似文献
68.
为了对钢制强化玻璃纤维制双层油罐贯通间隙空间进行优化设计,针对目前市场上主流双层油罐间隙空间的结构特点,应用计算流体力学数值模拟软件CFD,基于多相流流体体积模型,对双层油罐内罐发生渗漏后渗漏液体在贯通间隙空间的流动特点进行模拟计算。计算结果表明:液体在间隙空间流动时,其表面力对流动的影响占支配作用,体积力的作用可以忽略;当间隙垫片之间的距离≥0.8 mm,其对液体流动的阻碍作用开始减弱;主流双层油罐间隙空间的设计不合理,无法将油罐渗漏液体尽快引流到间隙底部。最后,根据液体在间隙空间的流动特点,对双层油罐间隙空间的设计提出了改进措施。 相似文献
69.
This paper studies load balancing for many-server (N servers) systems. Each server has a buffer of size b ? 1, and can have at most one job in service and b ? 1 jobs in the buffer. The service time of a job follows the Coxian-2 distribution. We focus on steady-state performance of load balancing policies in the heavy traffic regime such that the normalized load of system is λ = 1 ? N?α for 0 < α < 0.5. We identify a set of policies that achieve asymptotic zero waiting. The set of policies include several classical policies such as join-the-shortest-queue (JSQ), join-the-idle-queue (JIQ), idle-one-first (I1F) and power-of-d-choices (Po d) with d = O(Nα log N). The proof of the main result is based on Stein's method and state space collapse. A key technical contribution of this paper is the iterative state space collapse approach that leads to a simple generator approximation when applying Stein's method. 相似文献
70.
考虑到舰船环境限制和高能脉冲负载对储能的需求,有必要对储能装置进行合理的选型和优化配置,来提升综合电力系统性能。为此,基于带权极小模理想点法和层次分析法,提出了一种储能装置性能评价函数,并以其为优化目标,进行储能装置优化配置。所提出的评价函数充分考虑系统需求和脉冲负载特性,以储能装置体积、质量和经济性作为评价函数主要组成部分,同时考虑功率、能量、电压、荷电状态等约束,建立优化配置模型,并采用差分进化算法进行求解。以高性能锂电池和超级电容器为例,对所提模型进行求解计算,结果表明在所给权重系数下锂电池性能更优,更适用于综合电力系统,并给出了优化配置后的指导方案。 相似文献