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791.
针对经典Harris角点检测算法对于全局像素点求取角点响应函数所带来的计算复杂度高,从而不适合实时检测的弊端,提出了一种新的快速角点检测算法。鉴于角点数量只占整个图像像素点很小一部分,首先利用四方向亮度导数来进行候选角点预判断,阈值选取为图像像素点像素值的标准差的倍数。经过预判断后,再考虑8-邻域相似点个数,根据相似点个数对应的情况对候选角点进行再判断,将剩下的候选角点进行Harris算法检测。仿真结果表明,此改进算法能够有效地提高角点检测效果并减少检测时间。  相似文献   
792.
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   
793.
In this article, we explore when firms have an incentive to hide (or reveal) their capacity information. We consider two firms that aim to maximize profits over time and face limited capacity. One or both of the firms have private information on their own capacity levels, and they update their beliefs about their rival's capacity based on their observation of the other firm's output. We focus on credible revelation mechanisms—a firm may signal its capacity through overproduction, compared to its myopic production levels. We characterize conditions when high‐capacity firms may have the incentive and capability to signal their capacity levels by overproduction. We show that prior beliefs about capacity play a crucial, and surprisingly complex, role on whether the firm would prefer to reveal its capacity or not. A surprising result is that, despite the fact that it may be best for the high‐capacity firm to overproduce to reveal its capacity when capacity information is private, it may end up with more profits than if all capacity information were public knowledge in the first place. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
794.
针对现代战争条件下装备保障资源需求变化快,保障资源预测困难的问题,首先分析了影响装备保障资源需求的因素,根据实际情况选取了平均维修间隔时间(MTBM)、平均修复时间(MTBR)等8项影响装备保障资源需求的关键指标,然后将基于遗传算法(GA)优化的反向传播(BP)神经网络应用于保障资源需求预测中,构建了基于遗传神经网络的需求预测模型,最后利用1980年~2010年实际保障资源需求数据对模型进行了验证.验证结果表明,基于GA优化的BP神经网络预测模型有较快的收敛速度、较强的适应性和较高的预测精度,适用于装备保障资源需求预测.  相似文献   
795.
借鉴AHP法建立军械装备修理能力认证评估体系,并构建其递阶层次模型。确立体系各级指标权重中,引入D-S证据理论对多专家意见进行融合;综合考虑专家的权重和不确定度,并采用单值转换分布概率算法对专家评价分数进行换算,改进了AHP法受专家经验、知识限制,主观性强等缺点。经算例分析,该方法能准确可靠地评价型号装备修理机构的修理能力,减少专家主观因素对评估结果的影响。  相似文献   
796.
通过分析装备技术状态变化的模糊性和不确定性等特性,提出了基于云理论的装备技术状态预测模型.根据装备技术状态劣化趋势,给出了基于云模型的时间序列状态预测方法,有效地运用了装备状态评估中的主观预测知识.将历史趋势与当前趋势相结合,实现了基于时间序列的状态预测.最后以某装备的发动机为研究对象,对发动机状态的动态评估值进行了预测,验证了该状态预测方法的有效性.  相似文献   
797.
针对BP神经网络对初始值敏感、容易陷入局部寻优且收敛速度较慢,提出用粒子群对神经网络的参数进行优化,同时设计了衰减的指数函数对惯性权重进行动态调整以提高算法性能.并应用该算法对导弹飞控系统的逆误差进行补偿,仿真结果表明,该方法对逆误差进行了有效的补偿,避免了局部寻优并提高了学习效率.  相似文献   
798.
This article examines the ways in which the two normative concerns of casualty-aversion and civilian protection influenced US military strategy in the particular context of the asymmetric conflict in Somalia in the early 1990s. The article critically evaluates US military operations through the prism of international humanitarian law and examines whether American forces started prioritizing casualty-aversion over the safeguarding of Somali civilians. Finally, by drawing on emerging moral guidelines (such as Michael Walzer's idea of ‘due care’), the article examines whether lower numbers of Somali civilian deaths could have been achieved if marginal increases to the risks faced by US soldiers had been accepted.  相似文献   
799.
Since 2002 the Colombian government has been implementing a series of policy initiatives that have sought to coordinate state resources in a neo-classical counterinsurgency approach to fight the country's main insurgent group, the Fuerzas Armadas Revolucionarias de Colombia (FARC), and recover and consolidate the territory. Despite impressive operational successes against the insurgency and other illegal groups, the government has been unable to reassert its control and build legitimacy via the state-building effort known as ‘Consolidación’, in some of the most recalcitrant areas of the country. This article examines two areas where government efforts at consolidation appear to be failing to discuss the limits of COIN theory and practice.  相似文献   
800.
While Carl von Clausewitz has generally been respected as one of the most profound philosophers of war, his expertise has been regarded as somewhat limited if not even irrelevant to the so-called ‘new wars’ of the post-Cold War world. Many scholars in international relations have claimed that ‘new wars’ are essentially ‘post-Clausewitzian’ and ‘post-trinitarian’ in nature, meaning that they are no longer fathomable through a Clausewitzian framework. However Clausewitz's earlier writings were nearly exclusively dedicated to guerrilla warfare, or what he called ‘small wars’. These writings have been largely overlooked by many analysts of contemporary conflicts. By drawing on his rare and untranslated writings, the article uncovers a critical part of Clausewitz's expertise in asymmetric warfare and shows that, far from being irrelevant in an age where interstate warfare is increasingly being replaced by conflicts between states and semi-/non-state actors, Clausewitz's philosophical writings actually shed new light into the particular interactive dynamics generated during wars waged under conditions of asymmetry.  相似文献   
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