扭曲尾翼飞行器气动特性数值研究*

为研究扭曲尾翼对飞行器气动特性的影响,引入扭曲率与平均攻角来表示尾翼的几何特征,通过求解旋转坐标系下的定常状态N-S方程,对十字型布局扭曲尾翼飞行器气动特性进行了数值仿真。结果表明：扭曲尾翼可以增加飞行器的滚转力矩和平衡转速,其平衡转速与扭曲率呈正比关系;随着扭曲率的增大,扭曲尾翼飞行器未转动时的阻力系数增大、平衡转速时阻力系数减小;在临界扭曲率以内,随着扭曲率的增加,飞行器平衡转速时翼面压力分布得到了有效改善,研究结果对于飞行器的气动构型设计及其飞行稳定性分析具有参考价值。     

具有适应值预测机制的遗传算法

针对适应值计算费时的优化问题,提出一种具有适应值预测机制的遗传算法:为了有效控制预测适应值的准确度和预测频率,建立了一个基于可信度概念的适应值预测模型,引入可信度流失机制以减少预测误差的传播和累积,引入冗余个体剔除机制以减少计算消耗。利用3个基准函数对算法进行收敛性和有效性的测试,测试结果表明算法对于3个测试函数均能获得满意的最优解,并且都能减少60%以上的真实适应值计算次数。     

返回舱着陆工况对着陆冲击特性的影响

返回舱着陆工况对冲击响应特性有很大影响。建立了返回舱着陆冲击仿真分析模型,并利用已有试验数据对模型进行验证。通过显式非线性动力学分析方法模拟了返回舱着陆冲击过程,利用正交试验设计法进一步分析了返回舱着陆工况相关参数对冲击响应特性的显著性影响情况及其规律。结果表明:竖直速度、俯仰角、侧倾角及其因子间的交互效应对最大加速度的影响显著,水平速度和滚动角的影响作用不显著。这些结论可为返回舱地面相关试验和结构分析设计提供参考。     

基于非入侵式负荷小区用电设备监测技术

加强用电设备能耗的监测是我国提高电能利用率、实现能源可持续发展、建设节约型社会的重要手段。通过对国内外用电设备监测技术和方法的研究,以及对几种常用用电设备识别方式、原理和优缺点的比较,提出了一种基于非入侵式负荷的谐波电流面积监测技术。采用该技术对小区用电设备进行Matlab仿真,并对仿真结果进行分析和验证。结果证明该技术能提高用电设备的识别精度和能耗监测效率,对减少小区经济损失、提高电力系统稳定性、实现能源可持续发展具有一定的意义。     

Impacts of sequential acquisition,market competition mode,and confidentiality on information flow

We investigate information flow in a setting in which 2 retailers order from a supplier and sell to a market with uncertain demand. Each retailer has access to a signal. The retailers can disclose signals to each other (horizontal information sharing), while the supplier can solicit signals by offering retailers differential payments as incentives for signal disclosure (vertical information acquisition). In the base setting, market competition is in quantity, and a retailer can fully infer the signal that the other retailer discloses to the supplier. We show that the supplier prefers to sequentialize the procedure for information acquisition. Moreover, vertical information acquisition by the supplier is a strategic complement to horizontal information sharing between the retailers to establish information flow. In the equilibrium, the retailers have no incentive to exchange signals, but system wide information transparency can be realized through a combination of information acquisition and inference. We further study the signaling effect, whereby the supplier utilizes wholesale pricing as an instrument to affect the retailers' inference of the shared signals, and price competition to explore their impacts on the supplier's preference for sequential acquisition and the sustainability of information flow.     

对生化恐怖袭击抢险救援的思考

消防部队担负着处置生化恐怖袭击事件的抢险救援任务。在分析生化灾害及处置生化灾害的特点的基础上 ,提出提高消防部队处置生化灾害综合能力的措施。     

适应低时延业务需求的分布式可穿戴单兵作战信息系统

针对云计算应用在单兵作战系统场景下业务处理时延高、服务质量无法保障的问题,提出一种基于可穿戴计算的分布式单兵作战信息系统。利用士兵身上的可穿戴智能设备构建本地计算层,在作战地点就近处理计算数据,提供给士兵本地的信息处理与融合能力,并采用广义扩散负载均衡算法平衡各设备负载,降低业务处理时延;同时利用分布式计算的容错能力增强系统的可靠性。仿真结果表明,基于可穿戴设备的分布式本地网络架构能有效地降低作战任务的处理时延,同时增强系统的可靠性。     

舰空武器主要作战对象的特性及其模拟

了解主要作战对象的特性是舰空武器设计、试验必要的前提,也是空中靶标建设的关键,文章对此进行了归纳分析,提出了模拟这些特性的关键点,为舰空武器设计与试验、空中靶标设计与实现提供基本的结论。     

基于感知信息共享的C2网络特征分析*

指挥控制(C2,Command and Control)关系网络连接数的增加会增强指控节点之间的信息共享,但也会增加节点信息处理和交换负荷,如果达到一定程度,则会造成节点本身的"信息过载"从而影响C2网络性能.对此,通过研究C2网络在两种不同处理方式下的共享感知信息平均提交时间,用网络节点响应时间的均方差表征一个C2网络的共享态势感知时间的一致性,最后对两种不同结构C2网络特征参数的计算,说明了网络连接增加会导致信息提交时间的延长,但一致性会增强.     

Fleet management in European integration: the case of military helicopter support

The article focuses on both economics and spatial issues related to Maintenance Repair and Overhaul (MRO) of defence platforms in Europe. Using facts and figures related to costs, trends and fleet sizes evolution, the authors discuss the interest of a spatial reorganisation of MRO production. Given the fiscal situation of the main European countries with a modern army, the relevant scale to consider the reorganisation is certainly Europe. Through the example of defence helicopters fleets of a selection of European countries, the authors address the question of cooperation of the MRO. A greater cooperation in the support of fleets would lead to a spatial reorganisation of MRO. On one side economies can be expected from this reorganisation, but, on the other hand, new problems arise. Specifically, a number of costs associated with different forms of “distances” – geographical, operational and political distances – limit the potential savings that could be expected. This work provides insights on these important issues for the construction of a European defence, both in its political, military and industrial dimensions.