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101.
为研究悬臂式围护桩结构的内力、弯矩、位移和嵌固段的变化规律及特点,结合西宁火车站综合改造工程,对该深基坑支护结构在不同开挖工况条件下悬臂桩的受力性状与内力传递特征进行现场动态测试试验。试验结果表明:悬臂桩的受力特征与理论值有所差异,在实际设计中可对其在配筋方式、混凝土强度设计、嵌固段长度等方面进行优化。试验结果可以有效优化桩身设计,为复杂基坑在开挖过程中的支护结构受力及变形提供参考性依据。  相似文献   
102.
Secret French plans to launch guerrilla-style raids on the British Isles devised in the spring of 1796 were referred to as ‘chouanneries’. The name and concept behind these small-war operations were modelled on the irregular tactics used by the Chouan rebels in the Vendée, which the French state army had brutally quashed, but some wished to transfer into their institutional practice. Part of France's ongoing military strategy in the war against Britain, which included fomenting insurrection in Ireland, these irregular operations were to be manned partially by pardoned deserters and released convicts and prisoners of war. Of these, only Tate's brief invasion of Wales in 1797 was realised, but the surviving plans provide insightful historical lessons into an Anglophobic mindset shared by a small network of practitioners and policy deciders on the effectiveness of such shock and awe tactics. Largely motivated by the desire to take revenge for Britain's support of counter-revolutionaries in the Vendée, these plans could more aptly be referred to as counter-‘chouanneries’.  相似文献   
103.
针对非相干背景光辐照二波耦合中参数的最佳匹配设计问题,提出了一种基于随机共振理论的研究方法。首先,文章通过二波耦合过程进行物理机理分析和数值实验分析,证明了该问题在本质上可归结为一种随机共振现象。其次,从随机共振的角度,研究其中的最佳参数设计问题,给出了一种分布处理的最优参数设计流程。按照该方法,在给定增益要求的情况下,先根据信号光饱和与否来确定晶体长度,最后根据非相干光的比例对增益的影响来确定非相干光的比例。仿真实验表明,经过最佳参数设计后,信号的增益和输出信噪比上均有显著提高。  相似文献   
104.
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   
105.
This article modifies the associations made by historians and political scientists of Spanish guerrilla warfare with revolutionary insurgency. First, it explains how the guerrilla phenomenon moved from a Leftist to a reactionary symbol. Second, it compares the insurgency and counter-insurgency features of the Carlist War (1833–1840) with those of the better-known Peninsular War (1808–1814). Third, it shows how erstwhile guerrilla leaders during the Carlist War made their expertise available to the counter-insurgency, in a socio-economic as well as military setting. This article revises the social banditry paradigm in nineteenth-century Spain in the under-researched context of Europe bloodiest nineteenth-century civil war.  相似文献   
106.
This paper provides a political economy analysis of the evolution of unmanned aerial vehicles (UAV), or ‘drones’ in the USA. Focus is placed on the interplay between the polity and private economic influences, and their impact on the trajectory of political, economic, and military outcomes. We identify the initial formation of the drone industry, trace how the initial relationships between the military and the private sector expanded over time, and discuss present relationships. Understanding the historical evolution of UAV technology, as well as the major players in the industry today, is important for ongoing policy debates regarding the use of drones both domestically and internationally.  相似文献   
107.
While all governments in the region acknowledge the importance of the work of police officers, they seldom take a close look at their working conditions and the nature of police labour. While the situations in Namibia, Zimbabwe, Zambia, Lesotho and Swaziland are different there are commonalities: police management has not changed significantly and neither has police legislation. Key concerns of the officers in the region centre on service conditions and wages. Communicating these concerns to the state is made difficult by the less than democratic approach taken by governments professing to favour democratization. A more democratic workplace for the police is of benefit to the broader community and is a crucial point to bear in mind when attempting to develop community-oriented professional policing.  相似文献   
108.
If international terrorism is on a rising trend, an important source of confirmation or refutation of this is time‐series data on terrorist activity. Using chiefly data collected by the RAND/MIPT consortium we show using basic statistical analysis that in the period 1968–2005 the yearly number of all international terrorist incidents shows no trend over time, but fluctuates year on year in a random manner. On the other hand some indicators do show a definite trend over time, principally the steady rise in the number of incidents that are death‐dealing in nature. A further conclusion is drawn, showing that the proportion of these incidents leading to deaths above a given level is virtually fixed.  相似文献   
109.
介绍步进应力加速寿命试验原理,通过对制导弹药自动导引头贮存状态和失效机理的分析,确定了加速寿命试验应力和应力水平.假设产品寿命服从威布尔分布,应用极大似然估计和Bayes的方法处理数据,建立制导弹药可靠储存寿命预测模型,并计算得到自动导引头在正常应力水平下的可靠储存寿命.  相似文献   
110.
While Carl von Clausewitz has generally been respected as one of the most profound philosophers of war, his expertise has been regarded as somewhat limited if not even irrelevant to the so-called ‘new wars’ of the post-Cold War world. Many scholars in international relations have claimed that ‘new wars’ are essentially ‘post-Clausewitzian’ and ‘post-trinitarian’ in nature, meaning that they are no longer fathomable through a Clausewitzian framework. However Clausewitz's earlier writings were nearly exclusively dedicated to guerrilla warfare, or what he called ‘small wars’. These writings have been largely overlooked by many analysts of contemporary conflicts. By drawing on his rare and untranslated writings, the article uncovers a critical part of Clausewitz's expertise in asymmetric warfare and shows that, far from being irrelevant in an age where interstate warfare is increasingly being replaced by conflicts between states and semi-/non-state actors, Clausewitz's philosophical writings actually shed new light into the particular interactive dynamics generated during wars waged under conditions of asymmetry.  相似文献   
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