分级燃烧循环发动机变工况的模糊控制

研究了一种模糊控制方法 ,并用于分级燃烧循环液体火箭发动机变工况过程的反馈控制。仿真研究表明 :在抑制参数抖振方面 ,模糊控制优于一般的变结构控制     

红外热像仪标定方法

为了由红外图像得到目标的经度、纬度和高度信息,对目标精确定位,提出一种新的红外热像仪标定方法.以针孔成像模型作为红外热像仪成像模型,选择小热源作为标定点,以 WGS-84坐标系作为世界坐标系,引入北东天(NEU)坐标系,先通过借鉴主动视觉的思想控制热像仪绕光心旋转得到外部参数,然后借助GPS接收机测得标定点世界坐标,利用这些标定点的像素坐标和世界坐标由最小二乘估计求解内部参数.实验表明新方法精度高、成本低,适合于实际应用.     

A sequential auction‐bargaining procurement model

One of the most important decisions that a firm faces in managing its supply chain is a procurement decision: selecting suitable suppliers among many potential competing sellers and reducing the purchase cost. While both auctions and bargaining have been extensively studied in the literature, the research that combines auctions and bargaining is limited. In this article, we consider a combined auction‐bargaining model in a setting where a single buyer procures an indivisible good from one of many competing sellers. The procurement model that we analyze is a sequential model consisting of the auction phase followed by the bargaining phase. In the auction phase, the sellers submit bids, and the seller with the lowest bid is selected as the winning bidder. In the bargaining phase, the buyer audits the cost of the winning seller and then negotiates with him to determine the final price. For this auction‐bargaining model, we find a symmetric equilibrium bidding strategy for the sellers in a closed form, which is simple to understand and closely related to the classical results in the auction and bargaining literature. We also show that the auction‐bargaining model generates at least as much profit to the buyer as the standard auction or sequential bargaining model. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

后现代语境下对物理教师角色的理解

在教育改革逐步深入，课程改革全面开展之际，教师如何适应时代要求，尤其在物理这种基础理科教育中，物理教师怎样转变角色，后现代教育思想为我们提供了一个更为广阔的视角，以其多元的、不确定的、对话的、生成的思维方式去理解物理教师角色的内涵，在思想的深层重新建构物理教师角色。     

基于不确定语言多属性决策的目标威胁度排序

针对影响不同类目标威胁度的因素建立了目标威胁度指标体系,并在此基础上,利用不确定语言多属性决策模型对不同类目标威胁度进行排序。该方法不仅充分体现了不同类目标威胁度的影响因素,还充分利用了专家和决策人员的经验,能较好地反映现代战场中目标威胁度的实际情况,利于提高智能化程度;模型适应性较强,计算量小,符合军事系统实时性的特殊要求,使评估结果更具有可信性和实用性。     

小型固体运载器一、二级分离动力学与仿真研究

某低成本小型固体运载器采用侧喷流和栅格舵联合进行姿态控制。针对该布局,设计引入闭环姿态控制的一、二级级间冷分离方案。在描述级间分离过程的基础上,建立了分离运动学与动力学模型,解锁与分离冲量装置模型,气动力模型以及分离姿态控制律模型,讨论了碰撞判断条件,通过Monte Carlo仿真验证了参数不确定条件下分离姿态控制律设计对于避免碰撞和减小上面级初始姿态偏差的有效性。结果表明所设计的分离方案在充分发挥冷分离优势的同时能够弥补由冷分离时间长引起的上面级初始姿态偏差,能够有效避免级间碰撞。为该运载器的级间分离方案提供了一种可能的选择。     

机载DIRCM激光发射平台主支撑框架设计

机载DIRCM球型发射平台体积小、重量轻,跟瞄更为灵活、精确。应用有限元模态分析理论,对平台主支撑框架动态特性进行研究。通过建模,分析,确立最合理的设计方案。     

Modeling and solution for the ship stowage planning problem of coils in the steel industry

We consider a ship stowage planning problem where steel coils with known destination ports are to be loaded onto a ship. The coils are to be stowed on the ship in rows. Due to their heavy weight and cylindrical shape, coils can be stowed in at most two levels. Different from stowage problems in previous studies, in this problem there are no fixed positions on the ship for the coils due to their different sizes. At a destination port, if a coil to be unloaded is not at a top position, those blocking it need to be shuffled. In addition, the stability of ship has to be maintained after unloading at each destination port. The objective for the stowage planning problem is to minimize a combination of ship instability throughout the entire voyage, the shuffles needed for unloading at the destination ports, and the dispersion of coils to be unloaded at the same destination port. We formulate the problem as a novel mixed integer linear programming model. Several valid inequalities are derived to help reducing solution time. A tabu search (TS) algorithm is developed for the problem with the initial solution generated using a construction heuristic. To evaluate the proposed TS algorithm, numerical experiments are carried out on problem instances of three different scales by comparing it with a model‐based decomposition heuristic, the classic TS algorithm, the particle swarm optimization algorithm, and the manual method used in practice. The results show that for small problems, the proposed algorithm can generate optimal solutions. For medium and large practical problems, the proposed algorithm outperforms other methods. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 564–581, 2015     

基于“综合赋权”模糊物元模型的机场运行安全评价

为了保证机场运行安全,防止事故的发生,依据模糊物元分析理论,结合机场运行安全评价指标体系,构建了基于综合赋权的机场系统模糊物元安全评价模型。在该模型中,通过层次分析法和熵值法主客观综合所确定的权重,为指标体系进行线性加权,实现综合赋权,从而将计算得到的综合权重用于模糊物元建模与评价。实例分析结果表明,该模型步骤简单,过程科学合理,并兼顾了主客观因素的影响,评价结果总体反映了机场的真实安全水平,也为机场安全的科学评价提供了新思路。