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961.
After the fall of the Taliban regime in 2001, several thousand Afghan Taliban forces fled across the border to Pakistan, and the area became a safe haven for Afghan insurgents. In 2014, the transnational dimension of the insurgency is still highly prominent. Although regional support for insurgents is not uncommon, how to counter this aspect is mostly ignored in counterinsurgency (COIN) theory and doctrines. In this article, a regional counterinsurgency framework is developed, using the regional counterinsurgency efforts in Afghanistan as an example. The framework will facilitate the systematic inclusion of regional COIN measures in theory and doctrine.  相似文献   
962.
We introduce a generalized orienteering problem (OP) where, as usual, a vehicle is routed from a prescribed start node, through a directed network, to a prescribed destination node, collecting rewards at each node visited, to maximize the total reward along the path. In our generalization, transit on arcs in the network and reward collection at nodes both consume a variable amount of the same limited resource. We exploit this resource trade‐off through a specialized branch‐and‐bound algorithm that relies on partial path relaxation problems that often yield tight bounds and lead to substantial pruning in the enumeration tree. We present the smuggler search problem (SSP) as an important real‐world application of our generalized OP. Numerical results show that our algorithm applied to the SSP outperforms standard mixed‐integer nonlinear programming solvers for moderate to large problem instances. We demonstrate model enhancements that allow practitioners to represent realistic search planning scenarios by accounting for multiple heterogeneous searchers and complex smuggler motion. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
963.
Israel and Hezbollah have applied the lessons learned from the 2006 Lebanon War and have been preparing for a future conflict with both sides aiming for a more decisive victory. With improved capabilities from 2006, future hostilities will be far more destructive. This article analyzes their performance in 2006 and the lessons they have drawn to predict what a future conflict is likely to look like. The article analyzes both parties in three categories: ground forces; rockets, missiles, and anti-armor weapons; and lastly, Israel's air and sea dominance and Hezbollah's efforts to counter that dominance. Finally, this article argues that, contrary to conventional wisdom, a large-scale conflict between Israel and Hezbollah is unlikely to become a larger regional conflict involving Syria and Iran.  相似文献   
964.
Since 2000, international organisations such as the UN, NATO and the EU, but also countries, have started to apply what has been called the comprehensive approach to crisis management. This article unpacks this comprehensive approach implemented by the Dutch in Uruzgan province, Afghanistan. It first borrows and expands a conceptual framework developed by De Coning and Friis. Subsequently, it maps the different sorts of coherence in the mission by applying the framework. It shows how in practice there was not one single comprehensive approach, but many different forms of interaction between a number of organisational units. Each interaction had its own distinct issues and its own level of coherence. The level of coherence differed depending on the level at which the interaction took place – strategic at headquarters level versus operational at field level – and at what point in the mission it happened – in most cases it moved towards more cohesion.  相似文献   
965.
ABSTRACT

This paper challenges recent claims that competitive market dynamics incentivize Private Military and Security Companies (PMSCs) to fully commit to providing effective services, thereby reducing the duration of civil war. Our assessment of a most-likely case scenario for this argument – Sierra Leone – reveals four critical problems. First, there is rarely direct competition, even if numerous companies are present. Second, the presence of multiple PMSCs usually represents a collaboration among subsidiaries providing distinct services, often under the same corporate umbrella. Third, data aggregation obfuscates the overlap of PMSC presence, inflating the amount of perceived competition. Finally, we raise concerns regarding how quantitative analyses can conflate conflict intensity with conflict termination.  相似文献   
966.
As US counterinsurgency campaigns draw to a close, doctrine for asymmetric warfare written during the War on Terror has come under heavy criticism. While many have argued that this shift to ‘winning hearts and minds’ is evidence that the United States is taking humanitarianism and nation-building seriously, others argue that a wide gap exists between US counterinsurgency doctrine and the protection of civilians afflicted by conflict. In this article, I show that the latter is true by comparing theories of instrumental and communicative action to US doctrine for operational design, stability operations, and counterinsurgency. I argue that these texts treat the people as an object to be manipulated for the achievement of pre-determined self-interested strategic goals rather than members of a community that jointly designs operations to fulfill shared objectives. However, US doctrine does contain communicative elements that, if prioritized, would better support humanitarian and state-building objectives otherwise subordinated in the War on Terror.  相似文献   
967.
提出了一种小卫星姿态确定的非线性滤波算法,该算法利用三轴磁强计和光纤陀螺作为姿态敏感器。在非线性滤波器的设计中,从两个方面对平方根sigma点卡尔曼滤波方法进行改进。第一,把姿态四元数的矢量部分、光纤陀螺的漂移和噪声组合,得到滤波器的增广状态向量;第二,分别建立向量旋转模型、最优化模型和误差四元数乘法模型来确保非线性滤波过程中四元数的归一化约束。仿真分析结果表明,本文提出的非线性滤波算法能够有效地提高小卫星的定姿性能,与扩展卡尔曼滤波相比,具有较高的精度、稳定性和较快的收敛速度;与无迹卡尔曼滤波相比,收敛性相当,但是精度略优,稳定性和计算效率较高。  相似文献   
968.
合理安排导航卫星与地面上注站星地链路构建与导航电文上注,对保证星上导航电文的准确性和精确性有着重要意义。对卫星导航系统上行注入过程进行了分析,构建了上行注入任务调度问题的多目标混合整数规划模型,设计了基于规则的启发式求解算法。基于北斗二代和美国的GPS卫星导航系统构建仿真场景,仿真结果验证了模型和算法的正确性、可行性;通过分析仿真结果,得到影响卫星导航系统上行注入任务完成的关键因素。  相似文献   
969.
针对导航战、城市或者室内环境中,可见卫星数目小于3颗,用户位置未知时,接收机无法完成授时等问题,并结合我国已有卫星导航系统(北斗和CAPS系统)现状,提出了一种基于IGSO卫星的多普勒定位单向授时方法。该方法通过测量卫星信号的多普勒频移,采用积分多普勒计数计算用户位置,完成单向授时功能。分析结果表明,使用3颗IGSO卫星搭载透明转发器载荷,可使我国领土范围内的定位授时可用性基本达到100%;静态观测用户,长期测量定位精度可达3m以内,授时精度误差小于100ns。由于该方法最少只需观测1颗IGSO卫星信号,这为导航战背景及微弱信号环境下的定位授时服务,提供了新的解决方法。  相似文献   
970.
基于锁相环的GNSS授时接收机钟差校准算法   总被引:1,自引:0,他引:1       下载免费PDF全文
GNSS(全球卫星导航系统)授时接收机利用卫星导航信号获取钟差并校准本地时钟,从而与GNSS系统时间同步。提出了全新的基于锁相环的GNSS授时接收机钟差校准算法,将钟差校准过程等效为传统的锁相环模型,鉴相器的功能由PVT(位置、速度与时间)解算实现,压控振荡器的功能由本地时间调整接口实现,环路将本地秒相位与GNSS系统的秒相位锁定。分析了环路总误差的组成,以及环路参数与各误差项的关系,给出了误差最小的环路优化设计准则。在北斗二号卫星导航接收机平台上进行了对比实验,验证了算法的有效性。  相似文献   
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