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111.
在分析捷联惯导/里程计组合导航工作原理的基础上,就里程计辅助下的初始对准、里程计刻度因子在线标定、杆臂效应、系统故障处理等关键问题研究现状进行了分析,最后对未来的发展进行了预测。  相似文献   
112.
为了应对未来信息化战争对坦克装甲平台电子射频系统提出的更高要求,提出将综合射频系统应用在新型装甲平台上。该系统采用综合孔径方式设计,可完成对空目标搜索、精确跟踪、威胁判断、电子对抗、火力指引、毁伤评估等功能,在装甲平台防护中具有至关重要的作用。首先,介绍了装甲平台的多功能综合射频系统;其次,详细分析了该系统的组成、功能和特点,简要描述了作战中的应用模式;最后,针对综合射频系统在新型坦克装甲平台的进一步应用提出了发展建议。  相似文献   
113.
The building of reliable covers has always been of the utmost importance for clandestine Humint. Using both primary and secondary sources, this study seeks to examine how classical authors and modern scholars have dealt with this topic, and which kind of covers have been the most used throughout history in different sociopolitical contexts, and what are the new perspectives for today’s challenges. Findings suggest that a careful reading of the political milieu in which intelligence officers are required to work, and a certain degree of creativity, are the essential premises for the construction of a plausible cover; that some apparently outdated disguises such as merchants, itinerant monks and philosophers should be understood more broadly today to include business people, humanitarian NGOs and academics; that undercover practices have been theoretically and historically recognized as necessary and convenient by a great number of societies, often with scant regard for ethical considerations.  相似文献   
114.
Do ceasefires or peace talks create fragmentation in the insurgent groups? Rather than proposing claims that can offer predictions about armed groups behaviour under ceasefires or peace processes, the analysts tend to focus largely on the dynamics between state and non-state actor. The experts pay little attention to overtime changes in social and local political context which might contribute to propelling a rebel group towards fragmentation and factionalism. The present study intends to fill this gap by exploring the shifting role of public opinion and ethnic support for the peace talks to ascertain whether it can increase the likelihood of factionalism in rebel groups or not. This article applies this approach to the case of Naga National Movement (1947–2015) in India, and finds that the proposed variable appears to have increased the frequency of factionalism in the movement.  相似文献   
115.
Covert operations by underground groups, such as transnational terrorists, are not new and neither are the methods members of these groups use to communicate in their shadowy world. In this regard, one of the enduring myths is that the main means these covert operatives use to communicate within their cell structure are telephones and emails in their various manifestations. This article critically discusses the possible use of wireless transmissions by transnational terrorists as a reliable form of communications. To critically discuss this proposition, a force field analysis was used to assess the theory that radio is a viable option. Implications of this study's findings are considered in terms of the ramifications they have for defence and security policy.  相似文献   
116.
遂行非战争军事行动训练是公安现役部队教育训练的重要内容。近年来其训练效果在公安现役部队履职实践中得到了良好的体现。但面对日益复杂的斗争形势,公安现役部队在进行常规训练的同时,应更加突出应急训练、联合训练和心理训练,以更好地完成党和人民赋予的神圣使命。  相似文献   
117.
针对全球定位系统在信号失锁条件下与航位推算组合导航的系统误差快速累积问题,提出一种基于压缩扩展卡尔曼滤波的同时定位与制图的辅助的全球定位系统/航位推算组合导航方法。该方法利用同时定位与辅助实现运动平台在全球定位系统信号无效时连续稳定导航,抑制航位推算定位误差的累积,并利用全球定位系统定位结果校正同时定位与辅助制图误差,减小地图的不确定性。设计基于压缩扩展卡尔曼滤波的同时定位与辅助/全球定位系统组合滤波器,实现大尺度环境下同时定位与辅助/全球定位系统的实时解算。真实实验数据计算结果分析表明,相对于同时定位与辅助定位结果,同时定位与辅助的全球定位系统/航位推算组合导航可有效提高系统定位性能,使得制图精度提高10m。  相似文献   
118.
The creation of an African Capacity for Immediate Response to Crisis (ACIRC) is a sign of Africa's willingness to take its destiny into its own hands. Presented as a reaction to the slowness of the development of the African Standby Force (ASF), it is also a response to some of the ASF's conceptual weaknesses. This decision reflects a wish to establish an instrument better equipped to deal with the challenges Africa is facing. Departing from the (sub)regional logic of the ASF results from a desire to take into account the transnational nature of threats, while its enlarged mandate is meant to offer Africa the capacity to intervene in all kinds of conflicts, including by undertaking peace enforcement activities. But the obstacles on the road towards the actual creation and mobilisation of this capacity should not be underestimated. These include material difficulties, but also political tensions, between ‘small’ and ‘big’ states as well as between the African Union and subregional organisations. The risk then is high that the ACIRC, whose announcement came as a reaction to France's intervention in Mali, ends up joining the ranks of the many ‘anti-imperialist’ phantoms haunting the history of the Organization of African Unity/African Union (OAU/AU). Confronted by events considered ‘neocolonial’ initiatives, African actors have indeed traditionally reacted by launching grand projects that never got off the ground. However, by actually establishing this new instrument, they may also demonstrate that times have definitively changed.  相似文献   
119.
Abstract

The mandate of South Africa's recently appointed National Planning Commission includes addressing ‘defence and security matters’. This article seeks to outline the central elements of the threat environment facing South Africa in the foreseeable future. It is argued that South Africa faces no meaningful existential threat from conventional military forces but that its security forces will need to be prepared to address possible raids and attacks by conventional military forces both on home soil and on vital interests beyond the nation's borders. Other threats highlighted include the threats posed by potential insurgencies, by terrorism, and by crime, social unrest and banditry. Also addressed is the danger of so-called hybrid threats, in which two or more of the single threat types outlined here are combined. Finally, the article challenges the National Planning Commission to rethink South Africa's policy on peace operations in the light of the need to ensure the safety and security of the nation's citizenry.  相似文献   
120.
In Africa, most of the present conflicts are civil, intra-state wars where belligerent groups use guerrilla tactics to achieve various political, economic or ideological objectives. The atrocities and the effect of these on-going wars on innocent civilians, human suffering, poverty and development are beyond comprehension. Not surprisingly, the majority of current peace operations are in Africa, with more than 70 countries contributing forces to these conflict zones. On the continent, South Africa has come to assume a leading role in peace operations and is now a major troop-contributing country to UN and AU missions. In the past 11 years, the South African National Defence Force (SANDF) has taken part in no fewer than 14 peace missions. This article provides a brief background of the conflicts in Burundi, the Democratic Republic of Congo (DRC) and Sudan, the different United Nations (UN) and African Union (AU) mandates under which peacekeepers had to operate as well as their objectives, and the extent of South Africa's involvement in the various missions. In the last section, the major challenges, that these operations have posed are highlighted.  相似文献   
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