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1.
研究新公布的北斗民用导航电文中的两类历书与北斗二号导航电文历书的差异,对比分析各类历书对接收机首次定位时间的影响。利用实际的历书数据,比较不同历书类型的用户算法,分析不同龄期数据对接收机首次定位性能的影响。结果表明,高精度历书在1周的数据龄期内性能较为稳定,中等精度历书精度稍逊于高精度历书,但由于简化了电文空间,能接近高精度历书性能。简约历书进一步简化了参数数目和电文空间,尽管位置误差达到了数百千米,但却能在数月之后保持相应精度,有利于缩短接收机首次定位时间。  相似文献   
2.
The sword which is the subject of this article and which will be referred to as the Capel sword, is a fine example of what has become known as an Irish basket-hilt. Whilst there are other examples in existence, what makes this sword unique and particularly important is the fact that it is known to have been owned by two important Royalist military leaders, Lord Arthur Capel and Sir John Owen. These two extraordinary men came from different backgrounds but their fate was linked through circumstances beyond their control. The story this sword tells is one of comradeship, loyalty, total belief in a cause, betrayal and ultimate sacrifice.  相似文献   
3.
针对利用光纤光栅进行应变、温度等测量已经在土木工程中较为普遍这一现状,首先对光纤光栅传感技术进行应变、温度等测量的基本原理进行了描述,重点讨论了为满足耐久性、安装方便与温度自动补偿等需求光纤光栅传感器的封装技术,最后介绍了光纤光栅传感器在土木工程中实际应用的现状。  相似文献   
4.
The present-day conflict in Yemen is a valuable case study in the coercive use of airpower. The Saudi-led bombing campaign demonstrates the challenges inherent in applying a punishment-based strategy in a civil war, where coercive mechanisms operate differently than in interstate conflict. The audit from Yemen vindicates the effectiveness of a denial-based strategy and offers insights on the relative utility of interdiction and close air support in advancing that strategy. This examination dissects the campaign, assesses its effectiveness, and extracts insights useful both to the analysis of similar conflicts and to the evaluation of U.S. foreign policy alternatives.  相似文献   
5.
Abstract

Post-uprisings Middle East politics is frequently described as a ‘regional cold war’ involving proxy warfare that emphasises the role of shared identities linking external and local actors. But does the ‘content’ of identities impact proxy war dynamics? This article considers the present ‘battle for Syria’, a local conflict that became a theatre for multiple proxy wars involving actors emphasising identities on various levels, most notably national, religious/ sect and ethnic. It suggests that identity content does matter, with global powers more reluctant than regional players to back groups identifying at sub-national level, while foreign non-state actors are enthusiastic backers of sub-national identity.  相似文献   
6.
Armed groups are usually seen as threats to humanitarian action but less attention has been paid where they provide assistance to constituent populations. Ethnic armed groups (EAGs) in Myanmar have developed associated welfare organisations that perform this role. This article argues this is due to EAG social embeddedness and flexibility to changes in sources of funding and support, and the influence of their relations with international humanitarian organisations. This article further contends a subset of advocacy, health and education organisations have evolved to form a nascent civil society within the political and social non-state sphere of some established EAGs.  相似文献   
7.
The Sri Lankan Civil War (1983–2009) is regarded as a violent reflection of deepening divides along political and ethnic lines. During this civil war the Sri Lankan Government and its security forces have been implicated in unlawful killings carried out in a pervasive manner against civilians, whilst at the same time specifically targeting ethnic Tamils, humanitarian workers and journalists. The human rights of all citizens suffered as a result and ultimately led to the weakening of the rule of law. With the end of the civil war, the Sri Lankan Government has made little progress in providing accountability for wartime abuses. Its absence of and reluctance to ensure justice is seen as a logical culmination of decades of impunity. The importance of acknowledging historical behaviour and taking accountability for past violations will be discussed. In an analysis for paving the way to a new democracy in Sri Lanka, the main outcomes of this article are calls for accountability arising out of the government’s actions during the war; an investigation into the present state of human rights, the rule of law and finally; an examination into the political solution going forward to ensure a process of reconciliation and peaceful co-existence.  相似文献   
8.
Proxy warfare is a consistent element in international warfare. However, it is unclear why proxy relationships form in cases where states have multiple options of groups to support. Existing research identifies the presence of transnational constituencies, shared interstate rivalries, and moderate relative strength of militant groups as highly influential on the development of a proxy relationship. This study examines the presence of these variables within the context of the Lebanese Civil War. The results of this demonstrate that each state places greater importance on some variables and ignores others when choosing a proxy. Additionally, this study further demonstrates the presence of new variables that are key to the development of proxy relationships.  相似文献   
9.
针对目前绝大多数火药仓库的温度、湿度控制由于采用人工操作导致对温湿度不能实时精确监控从而导致火药失效的问题,设计了一种基于无线传感网和神经网络的火药贮存在线监测系统。该系统将无线传感网络终端节点实时收集到环境温度和水分信息传给神经网络控制器,根据神经网络控制模型实时调节火药贮存温湿度控制设备的各个参数,实现对火药贮存环境温湿度的自动化和实时精确控制,提高火药贮存的可靠性和经济效益。  相似文献   
10.
Using recent econometric techniques based on fractional integration, we find that developing countries recover their economic growth faster than developed countries in response to a shock. Following this methodology, we find that longer civil conflicts are associated with a faster recovery process. We further investigate this issue by exploring correlations with components of GDP, military spending, institutions and aid and find heterogeneous effects of these channels by duration of conflict. Higher government spending is correlated with faster recoveries post longer conflicts, and higher consumption spending is linked to faster recoveries following shorter conflicts. Military spending appears to be driving the government expenditure that makes countries recover from longer conflicts. More democratic institutions are associated with faster recoveries post short wars but slower recoveries following long wars.  相似文献   
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