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71.
针对齿轮箱启动过程中振动信号表现为非平稳、非高斯特征及传统诊断方法诊断精度不高的现状,将阶次小波包和粗糙集理论引入轴承的故障诊断中,提出了一种新的故障诊断方法。首先利用阶次跟踪算法对瞬态振动信号进行重采样,得到等角度分布振动信号,其次采用小波包对该信号分解—重构,并对每个频段的能量进行归一化,构成特征向量,通过粗糙集理论得到清晰、简明的决策规则,最后通过故障实例验证该方法的有效性。  相似文献   
72.
The South African Defence Review 2014 is the country's new defence policy. The Review, which is expected to steer South African defence policymaking for the next few decades, discusses in detail the role of the South African National Defence Force (SANDF) in peace missions in Africa and proposes the direct involvement of the country's soldiers in both military and civilian tasks, from peacekeeping to humanitarian assistance, post-conflict reconstruction and development. This paper contains a critical review of the Review with regard to South Africa's envisaged contribution to regional and continental peace and stability. It is argued that humanitarian assistance and post-conflict reconstruction should not be securitised and that the SANDF should only be tasked with peacekeeping and the establishment of stability and security in fragile in-conflict and post-conflict settings. The humanitarian work should be left to humanitarian and aid agencies, while reconstruction and development should be left to organisations such as the New Partnership for Africa's Development, continental and international development organisations, and local actors.  相似文献   
73.
Based on primary and secondary data, this paper provides a qualitative account of current changes in the pattern of natural resource management as a result of resource degradation and conflict in the Borana rangelands of southern Ethiopia. Population pressure, recurrent drought and the depleted carrying capacity of pastoral resources, as well as the encroachment of neighbouring ethnic groups, present the Borana community with a significant challenge. The diminishing resilience of traditional politico-judicial institutions under the famous Gada system often result in the rise of new forms of land use such as farming and private enclosures, which compete with the traditional communal tenure system. The gradual collapse of traditional norms and value systems and the apparent inefficiency in the formal administrative structures have exacerbated the problems of resource degradation and conflict between multiple resource-users.  相似文献   
74.
在基于模型的故障诊断仿真系统的诊断流程中,由最小冲突集计算最小碰集是整个流程中的关键步骤。针对现有计算最小碰集方法中存在的缺陷,提出了运用集合逻辑运算法计算最小碰集,将冲突集表示为集合的逻辑"与"、逻辑"或"运算,通过其运算法则进行运算简化,可得到全部的最小碰集。该方法具有简单有效、数据结构简单、计算简便快捷和易于程序实现等优点。最后通过实例计算,验证了该算法的正确性、简单性和高效性。  相似文献   
75.
文化依附问题在翻译中至关重要。本文用若干有说服力的译例从文化偶合、文化并行、文化冲突、文化空缺四个方面介绍分析了在翻译过程中如何处理文化依附矛盾的问题。  相似文献   
76.
基于模糊集和证据推理方法的武器系统可靠性评估   总被引:1,自引:0,他引:1  
提出了一种评估武器系统可靠性的新方法。在这种方法中,武器系统中各组成部分及零部件的可靠性用模糊语言变量来表示,利用证据推理方法合成各子系统零部件的可靠性评估结果,提高了各子系统的可靠性水平。文中以某高炮系统的可靠性评估阐述了该方法的应用情况  相似文献   
77.
Pirate attacks against commercial vessels in the Western Indian Ocean and nearby seas reached an unprecedented level in 2011. Despite concerted efforts by the international community and shipping companies to address this threat by conducting naval patrols and equipping commercial vessels with non-lethal defenses, the frequency of pirate attacks continues to increase. The general ineffectiveness of existing anti-piracy measures has sparked interest in expanding the use of armed private security contractors to protect commercial vessels from pirate attacks. This article argues that armed private security contractors can, indeed, enhance the security of commercial vessels because these actors can provide onsite protection for commercial vessels, which should allow them to respond very quickly to pirate attacks, and because these actors are willing to use deadly force against pirates. However, this article also argues that expanding the use of these actors may increase the degree of violence used during pirate attacks, pose threats to the safety of innocent civilians, and violate a number of domestic and international laws.  相似文献   
78.
This article examines the ambiguous role played by the Cyprus Police Force during the Greek Cypriot insurgency against Britain between 1955 and 1959. A multiethnic force policing a multiethnic society, the CPF struggled to fulfill its duties. Greek Cypriot officers became ineffective as sympathy for, or fear of insurgents undermined their ability to function. Some collaborated, others resigned. Those who stayed became targets of their own people. Turkish Cypriot officers, recruited in greater numbers to compensate for a reduction in Greek Cypriot officers, worked to enforce the law, but exacerbated intercommunal relations in doing so. In spite of the peculiar conditions present in Cyprus, the case has valuable implications for contemporary policymakers on the vulnerabilities inherent in the use of local police forces to restore law and order in ethnically divided societies.  相似文献   
79.
Soon after India attained its independence from British colonial administration in 1947 the Nagas started waging an armed conflict against India to establish a sovereign independent state in Nagaland in the country's Northeast region. The conflict is today one of the world's longer running and little known armed conflicts. India's central government has tried unsuccessfully to tackle the problem through political reconciliation, use of force, and several development measures. Over the years, it has also undergone several changes in which the situation of conflict deepened whenever India's central government intervened. And yet, the road ahead also faces severe challenges because the demand for bringing the Nagas of India together into a single political entity will not go unchallenged from other ethnic groups. Moreover, a bitter leadership battle divides the Naga rebels and hence any future agreement is likely to be difficult due to factional politics as have happened in the past. Thus one way to satisfy the aspirations of different ethnic groups while protecting the boundaries of the existing states in India is to explore the option of cultural autonomy. This idea is not entirely new, but has lost significance over the years.  相似文献   
80.
Abstract

A tremendous amount of important work has been done recently on operationalising the protection of civilians as a military task. The bulk of the discussion has focused on how militaries should respond to direct attacks on civilians. This is an important issue, but thinking about civilian protection should also include a serious examination of the ways in which the approach of military organisations to the problem of ‘spoiler’ groups can affect the level and dynamics of attacks on civilians – importantly, where armed groups are interested in violent control of civilian populations, attempts to ‘dislodge’ them from areas of control may substantially increase the level of violence against civilians (beyond the dangers to be expected from being near areas where active fighting is taking place). In 2009, the United Nations mission in the Democratic Republic of Congo (MONUC) supported the Congolese military in operations to dismantle the Hutu-dominated FDLR (Forces Démocratiques de Libération du Rwanda, Democratic Forces for the Liberation of Rwanda) militia group, at massive human cost. Critics have primarily focused on MONUC's failure to protect civilians from direct attack, consonant with the general discourse on tactics for civilian protection. These criticisms are valid, but in this paper I argue that two crucial additional considerations should be kept in mind: the way that military operations can affect violence against civilians, and the way that moralising the approach to armed groups, even those which have committed serious abuses, can limit military and political options – potentially in ways that increase civilian risk in the name of protecting them.  相似文献   
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