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131.
介绍了北斗、短波授时技术;对高稳恒温晶振及其频率特性进行分析的基础上,设计了一种基于北斗卫星、短波无线电授时的高精度时钟系统;该系统通过利用北斗接收处理模块、短波授时接收模块得到的秒脉冲信号、时间信息,经过延迟修正处理、脉冲滤波、脉冲补偿、脉冲统计得到标准的秒脉冲信号,实现对恒温晶振频率的校准,获得一个短期及长期频率稳定度都比较优良的时间频率标准,同时利用校频后恒温晶振分频出的1pps信号对时间芯片进行校准,对外输出高精度时间信息;对恒温晶振校频系统的基本工作原理及部分模块电路图进行了说明,试验结果表明,在时间不长于1h内,频率准确度优于1×10-10;该系统实用方便的方法达到了将晶体振荡器校准到较高指标的目的。  相似文献   
132.
This article had its genesis in a background study for the development of a new Australian Army counter-insurgency doctrine. Archival research showed that the Australian counter-insurgency doctrine employed in such post-1945 conflicts as Burma, Malaya, Borneo and Vietnam originated in the jungle campaigns of the South West Pacific Area during World War II. The historical record also showed that the Army's counter-insurgency doctrine, as with its World War II-jungle warfare doctrine, was a pragmatic amalgam of Australian experience and British doctrine. The article traces this process through the development of a series of doctrine manuals. It also considers the contribution of key individuals to both counter-insurgency theory and practice. This distinctively Australian approach to the development of doctrine was responsible for producing a highly successful manual, The Division in Battle: Pamphlet No. 11, Counter-Revolutionary Warfare (DIB 11), which the Army used during its involvement in Vietnam.  相似文献   
133.
内编队系统通过实现内卫星纯引力轨道环境和内卫星精密定轨,完成高精度地球重力场测量,实现了不依赖于加速度计的重力卫星实施新途径。针对内编队重力场测量性能难以解析分析的情况,基于MATLAB并行程序设计进行了重力场测量数值模拟,获得了内编队重力场测量的有效阶数及其精度。在内编队轨道高度为300km、内卫星干扰力为1.0×10-10m/s2、外卫星定轨精度为3cm、内外卫星相对状态测量精度为1mm的条件下,计算得到内编队测量重力场的有效阶数为72,相应的大地水准面累积误差为44cm,重力异常累积误差为4.5mGal,由此可知内编队测量重力场的有效阶数主要分布在低阶部分。  相似文献   
134.
基于组合赋权雷达图实现电网电能质量综合评估   总被引:1,自引:0,他引:1       下载免费PDF全文
将改进的组合赋权雷达图方法用于电网电能质量综合评估。对主观、客观赋权法组合,基于组合权重与原权重之间的偏差尽可能小的优化思想,求取雷达图中各项指标的组合权值。利用各指标对应的扇形区域的对角线作为指标轴绘制雷达图,不仅最大限度体现各指标的独立权重,也反映了各指标之间的相互影响。利用雷达图的面积和周长两个变量完成对电能质量的综合评估。最后通过应用实例,验证了论文方法的合理性和在电能质量综合评估中的有效性。  相似文献   
135.
基于联合相似测度的SAR图像边缘点特征配准方法   总被引:1,自引:1,他引:0       下载免费PDF全文
针对SAR图像配准过程中几何变换影响特征匹配稳健性和适应性的问题,提出了一种在特征匹配过程中直接解算几何变换模型的边缘点特征配准方法。利用SAR图像边缘点的梯度和方向特征,基于像素迁移思想,定义了图像匹配的联合相似度——联合特征均方和(SSJF),并建立了SAR图像边缘点集相似性匹配准则;基于方向模板提出了改进的ROEWA算子;利用改进的遗传算法(GA)来进行相似度的全局优化搜索,获取配准模型参数;利用多幅SAR图像的配准试验,对本文方法的性能进行了验证。  相似文献   
136.
This study develops the concepts of fourth generation operations and the associated principles. First, the concept of fourth generation operations is introduced and defined. Fourth generation operations are the evolution and extension of third and fourth generation warfare based on a change of tactics, technology, and combatants. These operations are currently ongoing in Afghanistan and Iraq, and with the global war on terrorism. Based on the framework of US joint doctrine, the supporting principles of fourth generation operations are developed. This requires the introduction of the principle of Population Perception.  相似文献   
137.
ABSTRACT

This article discusses the Rhodesian Front regime propaganda warfare strategy during Zimbabwe’s war of liberation. It uses the case of the Chilonga area of Chiredzi located in the south-east of Zimbabwe to demonstrate that propaganda warfare was introduced as a measure to counter guerrilla infiltration and civilian cooperation with them. Drawing on ideas of military anthropology vis-à-vis the importance of cultural awareness in counterinsurgency, the paper argues that the efforts of the Rhodesian Front regime to use propaganda were fruitless. This is because they mostly ignored the culture of the Shangani, local people. Despite that, there were other reasons for the failure of the Rhodesian Front’s propaganda strategy, including the lack of conformity between politics and military action.  相似文献   
138.
This article explains the demise of Sierra Leone's Revolutionary United Front (RUF) rebellion. It argues that the main cause of this fate was the group's relationship with its primary sponsor, Charles Taylor. The RUF's dependency on Taylor's patronage, coupled with the rebellion's weak organisational endowments harmed the group's prospects of success. Based on original research, the article shows how Taylor used the RUF as a strategic instrument for his own regional interests, which led to the group's unravelling. More broadly, the article speaks about proxy warfare in Africa and how the relationship between resource flows and rebellion are not always beneficial to rebels as one might expect.  相似文献   
139.
Abstract

The 1919-1921 Anglo-Irish War represents one of the earliest instances of a successful insurgent movement in the twentieth century. By combining a fluid organizational structure with effective hit-and-run tactics and accurate intelligence, the Irish Republican Army was able to defeat militarily the security forces of Great Britain. Combined with a successful propaganda campaign, these tactics allowed the IRA to drive the British to the negotiating table, where its representatives secured greater autonomy than Ireland had known in centuries. The outcome of the Anglo-Irish War demonstrates the success which a well-organized guerrilla campaign can achieve, and the tactics used by the IRA must therefore be understood by any serious student of small warfare.  相似文献   
140.
ABSTRACT

This paper evaluates Boko Haram’s military capabilities and details the process of how its standing army, driven by these capabilities, came to pose a phased threat between 2013 and 2015 in particular. This was a period when military fighting dominated the insurgency in north-east Nigeria. Whereas there is an abundance of literature on Boko Haram’s histories and the impact of its insurgency on north-east Nigeria, analysis of Boko Haram’s military campaigning is still deficient. Attempting to fill this gap, this paper uses field findings and battlefield case studies from north-east Nigeria to highlight how Boko Haram’s overt front – its standing army – came to supplant its guerrilla operations as the main security threat to the frontier area.

This pivot towards military fighting, for a group initially composed of a few ragtag combatants, on the surface might seem surprising. Yet, whereas Boko Haram may lack the popular support required for ‘people’s war’, classic insurgency theories nevertheless hold some explanatory power for this deliberate shift: away from guerrilla warfare as the expedient of the weaker side, and towards the use of a large standing army of locals to swarm, and sometimes successfully overrun, state forces.  相似文献   
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