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1.
突破传统全球导航卫星系统(Global Navigation Satellite System, GNSS)层析反演研究忽略地球磁场对电离层变化活动的影响,同时顾及不同电离层高度电子密度变化较大的影响,提出在地磁坐标系下建立电离层高度方向上不等像素间距的GNSS层析反演方法。在此基础上,通过建立新的电离层层析迭代松弛因子,提高GNSS电离层电子密度层析反演结果精度。利用IRI—2007电离层模型、GNSS实测数据与电离层测高仪数据,从模拟验证和实测数据对比两方面,反演统计了不同层析算法估算的峰值电离层电子密度误差、电子密度剖面结果平均绝对百分比误差及均方根误差,验证了顾及地磁影响的GNSS电离层层析不等像素间距算法的有效性。  相似文献   
2.
《美苏消除两国中程导弹和中短程导弹条约》的失效重创了本就脆弱的国际军控体系,对美俄战略稳定和全球军事安全带来消极影响,国际军控合作和全球军事安全迫切需要重构新的军控体系。本文立足当前国际军控现状,在分析美俄“退约”背后各方战略考量及国际军控面临的挑战,如“美国优先”理念下的霸权主义和单边主义、国际军控体系自身的脆弱性和局限性和新军事革命给全球安全增添新的变量的基础上,提出了“构建人类命运共同体”理念凝聚全球安全共识、以大国责任和义务为基础构建多层次军控体系和以多边军控体系循序推进国际军控进程等措施和建议,以期为推动国际军控合作,建立更为公平、合理、有效的国际军控体系做出贡献。  相似文献   
3.
Cyberspace experiences worrying trends that could have a negative impact on the international strategic landscape. The lack or erosion of norms and risky practices and behaviors could lead to greater uncertainty and thus greater instability. Set against a context of renewed competition between great powers, these developments are also tied to the strategic structure of cyberspace. This forum is devoted to discussing factors leading to stability or and instability.  相似文献   
4.
There has been near-universal condemnation of the use of chemical weapons in the Syrian conflict. The international community has nevertheless struggled to make progress on holding the perpetrators to account. This article reviews developments at the international level in terms of Syrian chemical weapon justice between 2011 and 2017. It argues that there have been substantive disagreements between states on the rationale and means of justice in the Syrian case. It also argues that international initiatives have been tightly intertwined with developments in chemical disarmament and conflict resolution processes as well as the broader war. The article describes progress and challenges to chemical weapon justice in a number of distinct formal international mechanisms during the period studied. The analysis concludes by contextualizing international responses—including the U.S. tomahawk strikes against a Syrian airbase—to the Khan Shaykhun chemical attacks of April 2017.  相似文献   
5.
使用检查是发现工程安全设施系统隐蔽功能故障的有效措施。在考虑检查期间可能发生运行故障的前提下,建立了基于使用检查策略的系统可用度模型。应用该模型对应急柴油发电机的使用检查过程进行可用度分析,确定了其最优检查问隔期和给定可用度条件下的检查间隔期区间;探讨了检查时间和维修时间对可用度的影响。研究表明,该模型对于工程安全设施系统的可用度分析是有效可行的,其结果能够为维修决策提供依据。  相似文献   
6.
US national security guidance, as well as the US Army’s operational experiences since 2001, emphasizes the importance of working closely with partner countries to achieve US strategic objectives. The US Army has introduced the global landpower network (GLN) concept as a means to integrate, sustain and advance the Army’s considerable ongoing efforts to meet US national security guidance. This study develops the GLN concept further, and addresses three questions. What benefits can the GLN provide the Army? What are the essential components of the GLN? What options exist for implementing the GLN concept? By developing the GLN concept, the Army has the opportunity to transition the GLN from an often ad hoc and reactive set of relationships to one that the Army more self-consciously prioritizes and leverages as a resource to meet US strategic objectives.  相似文献   
7.
Many African states have security sector reform (SSR) programs. These are often internationally funded. But how do such programs account for previously existing security institutions and the security needs of local communities? This article examines SSR all over Africa to assess local ownership and path dependency from a New Institutionalist perspective. It finds that SSR, particularly in post-conflict countries, tends to be driven by ideas and perceptions of international donors promoting generalized blueprints. Often, such programs only account in a very limited way for path-dependent aspects of security institutions or the local context. Hence, the reforms often lack local participation and are thus not accepted by the local community eventually.  相似文献   
8.
界水管理过程中,对于界河(左右岸界河)和国际河流(上下游界河)应明确其不同的主要矛盾,根据我国应对界水问题的基本规则,解决使用和管理中的各种问题。在此基础上,参照地区惯例,积极参与国际条约的制订和完善,以期进一步提高我国界水管理工作的水平。  相似文献   
9.
随着经济贸易的全球化,高等教育国际化已经成为当代高等教育发展的必然趋势。留学生教育已经成为衡量高等教育发展状况的重要指标。本文用SWOT分析法剖析新疆高校发展留学生教育所具有的优势、劣势以及面临的机遇和威胁,为新疆高校制定适合本地留学生教育的未来发展战略提供依据,以推动新疆高校留学生教育的快速发展。  相似文献   
10.
Since the July 2009 Boko Haram terrorist outburst in Nigeria, there have been increasing questions on the phenomenon in the country. There has not been any substantial analysis on the emergence of the Boko Haram group and its terrorist activities in Nigeria as the out-rage continues. This study is advanced to explain the phenomenon of Boko Haram terrorism in Nigeria. It employs the levels of analysis framework popular in the field of international relations to explain the terrorism at three major levels: individual, state and international. The study relies on dependable news reports, which include interviews with key actors relevant to the subject matter, and finds that Boko Haram terrorism has its roots in the ideology and motivations of its founder and members, the failures and deficiencies of the Nigerian state, and the modern trend of religious terrorism in the international system.  相似文献   
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