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851.
为了保证无线传感器网络中数据的完整性,针对基于LEACH路由协议的动态轮时间算法存在的问题,提出一种基于人工神经网络的数据预测算法。该动态轮时间算法中,部分簇因调整后的轮时间不足以完成数据的采集而丢失数据。数据预测算法结合传感器节点数据具有时空相关性的特点,将时空延迟算子引入神经网络模型,并通过建立的神经网络模型对数据进行预测。仿真时采用伯克利英特尔实验室的传感器数据,通过Mafl软件对模型进行测试并分析仿真结果。实验结果表明:该算法对连续多个数据的预测效果理想,预测误差始终保持在较低水平。 相似文献
852.
Roger Arditti 《Small Wars & Insurgencies》2013,24(5):764-789
It has long been held that the Federation of Malaya’s counter-insurgency campaign during the First Malayan Emergency (1948–60) was determined by the use of intelligence. Special Branch — the Federation’s primary intelligence agency — dominates the prevailing paradigm of how the insurgent threat was tackled. Conversely, the role of the Royal Air Force (RAF) within this paradigm is very limited. Most observers simply dismiss the role of photoreconnaissance or airstrikes as being largely inconsequential to the counter-insurgency effort. This is perhaps understandable: the Emergency was after all a ‘policing action’ and the insurgents were largely hidden under Malaya’s jungle canopy and amongst the Chinese community. However, further scrutiny reveals that the RAF made a much more significant contribution to the intelligence element of the counter-insurgency campaign than previously realised. First, the RAF decided to locate their Advanced Headquarters with the Army’s General Headquarters. This led to the creation of the Land/Air Operations Room, through which intelligence, tasking and resources were coordinated. Moreover, the RAF put its intelligence teams into the field to provide a practical link between local units and theatre-level assets. Second, with the support of the Army, the RAF established at the beginning of the Emergency the Joint Air Photographic Intelligence Board (Far East). This coordinated all photographic intelligence requirements throughout the Emergency, which was then delivered via the Joint Air Photographic Centre (Far East). Hence, via Joint Operations Centre and JAPIB (FE), the RAF provided both the practical means for effective joint intelligence operations at theatre level throughout the Emergency. 相似文献
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复杂的飞行器系统容易同时受到外部干扰和时滞的影响,为改善该系统控制性能设计一种新的基于干扰观测器控制策略.通过构造辅助观测器以及适当的坐标变换观测将来时刻的干扰,得到相应的干扰预测规律.与传统的鲁棒控制律结合,能够保证系统的稳定性,同时干扰的影响可以得到实时补偿.仿真结果表明该方案在外部干扰和时滞共同作用下具有较好跟踪特性. 相似文献
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在可视导航卫星数少于四颗、无法进行传统导航解算的恶劣环境下,导航接收机可利用外部高程气压计提供的高程或者内部守时模块的钟差等信息进行应急辅助定位。在该应急辅助定位工作模式的误差分析中,传统导航定位误差传递模型无法适用。针对此问题,本文在研究三星结合高程、三星结合钟差、双星结合高程钟差等几种应急辅助定位原理的基础上,给出了新的应急辅助定位误差传递的分析模型,利用仿真算例验证了该模型的正确性。通过对定位精度的分析,说明根据卫星分布特点可以按照本文方法量化得到伪距测量与辅助信息的精度的最优数量级关系,可以用最小代价实现定位精度的提升。该结论可指导接收机外部辅助器件的选择。 相似文献
858.
Eitan Shamir 《战略研究杂志》2013,36(5):645-672
The purpose of the current paper is to examine the adoption and adaptation process of mission command (Auftragstaktik) in the US Army. This concept, developed by the Prussians, denotes a decentralized command approach wherein superiors dictate their intent and allow subordinates to formulate their operational plans independently and change it according to the emerging situation. The paper examines the US command approach prior to the adoption of mission command. It argues that it was heavily influenced by corporate management practices which inherently contradict mission command approach. It continues and investigates how the US Army endeavored to emulate the approach in its doctrine and in major operations. While it has officially incorporated mission command into its doctrine, it has been less successful in utilizing it in operational situations. This state of affairs has to do with the cultural legacy of the managerial approach to command that still persist. Despite the partial success, the US Army has recently reaffirmed its commitment to this approach. 相似文献
859.
C. Christine Fair 《战略研究杂志》2013,36(2):259-290
This article uses a novel database of 1,625 posthumously published biographies of members of two Islamist militant organizations (Lashkar-e-Taiba (LeT) and Hizb-ul-Mujahideen (HM)), all of whom were killed in the course of carrying out militant attacks. In general, each biography provides data on the militant’s birthplace, education, recruitment, and training. The number of observations in this database is a full order of magnitude larger than those of previous databases assembled from militant biographies. While the sample of militants in this database is the product of multiple selection effects, analysis of the database undermines many common myths about Pakistani militants and casts doubt on current policy approaches to mitigating Islamist militancy in Pakistan. 相似文献
860.
VIKRAM JAGADISH 《Small Wars & Insurgencies》2013,24(1):36-65
Over seven years after the 11 September 2001 attacks on the United States, Afghanistan is again at the forefront of the headlines, faced with a brutal insurgency and a resurgent Taliban. Many scholars and policymakers attribute the instability in Afghanistan to a terrorist sanctuary in the neighboring Federally Administered Tribal Areas (FATA). Pakistan has attempted to eliminate this sanctuary through negotiation and armed force. This paper argues that Pakistani strategy has failed to achieve its desired results because of local tribal norms, the weak nature of previous agreements, military units ill-equipped for a counterinsurgency and counterterrorism role, as well as ideological fissures in the Pakistani establishment. Afterward, the paper argues that the United States and Coalition forces should pursue their strategy remaining cognizant of local tribal norms, step up training efforts for Pakistani forces, promote development of the tribal areas, and cultivate options for eliminating the FATA sanctuary through covert means. 相似文献