坦克激光测距在虚拟仿真中的研究与实现

激光测距仿真是坦克火控模拟训练系统的一个重要组成部分,也是构建坦克射击虚拟战场环境仿真研究的重点.以坦克激光测距为仿真研究对象,依据光点式火控系统功能模拟原理和激光测距机性能指标,建立了三维视景中激光测距仿真的变换模型,实现了火控仿真系统中坦克对任意目标的激光测距.该模型仿真精度较高,效果逼真,对提高坦克射击乘员在观察测距、瞄准目标的训练成绩上有较好的促进作用.     

Dynamic coordination of production planning and sales admission control in the presence of a spot market

We consider the decision‐making problem of dynamically scheduling the production of a single make‐to stock (MTS) product in connection with the product's concurrent sales in a spot market and a long‐term supply channel. The spot market is run by a business to business (B2B) online exchange, whereas the long‐term channel is established by a structured contract. The product's price in the spot market is exogenous, evolves as a continuous time Markov chain, and affects demand, which arrives sequentially as a Markov‐modulated Poisson process (MMPP). The manufacturer is obliged to fulfill demand in the long‐term channel, but is able to rein in sales in the spot market. This is a significant strategic decision for a manufacturer in entering a favorable contract. The profitability of the contract must be evaluated by optimal performance. The current problem, therefore, arises as a prerequisite to exploring contracting strategies. We reveal that the optimal strategy of coordinating production and sales is structured by the spot price dependent on the base stock and sell‐down thresholds. Moreover, we can exploit the structural properties of the optimal strategy to conceive an efficient algorithm. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

数字阵列雷达及其关键技术进展

随着高速ADC器件和高性能通用处理器的发展,雷达的数字化程度越来越高。分析了数字阵列雷达的优点;介绍了现有的典型数字阵列雷达系统,总结了数字阵列雷达的典型结构;介绍了高速ADC器件、高速采集板、正交解调和通道均衡等关键技术的发展现状。随着相关技术的不断进步,阵列雷达必然向着数字化、软件化和多功能的方向发展。     

河道型水库区下垫面和地形改变对局地降水量影响

河道型水库区降水由于受到库区地形和下垫面改变的影响,研究降水与地形和下垫面改变之间的关系对于库区的生产生活非常重要。依据水汽循环理论,考虑了地形起伏引起的气流运动路径改变,以及下垫面变化引起的水库区渗透量、蒸发量和地面植被截留量的变化,推导出局地降水量与地形起伏和下垫面改变之间的关系,以三峡库区重庆段为例,对结果进行验证。计算结果表明：在下垫面改变和地形升高的作用下,年均降水量有所增加,计算结果与库区气象站检测结果较为接近。     

OFDM水声通信自适应调制算法研究

分析预估信道长度对信道估计算法的影响规律,提出了利用水声通信均衡恢复信号统计量对信道估计质量实时评估的方法,通过信道长度自适应修正机制,实现了对未知水声信道高精度、快速估计;针对水声信道造成的OFDM子载波特性差异,基于信道估计结果,提出了在码元总速率、能量约束条件下,各个OFDM子载波局部速率、功率优化分配的自适应调制算法,相比于传统的等功率、速率分配算法,新算法能够显著提升水声通信系统的误码率性能,通过仿真和实地试验,验证了本文研究内容的有效性。     

The effect of a temporary product distribution channel on supply chain performance

We analyze a supply chain of a manufacturer and two retailers, a permanent retailer who always stocks the manufacturer's product and an intermittent deal‐of‐the day retailer who sells the manufacturer's product online for a short time. We find that without a deal‐of‐the‐day (DOTD) retailer, it is suboptimal for the manufacturer to offer a quantity discount while it is optimal for the retailer to offer periodic price discounts to consumers. With the addition of a DOTD retailer, it is likely to be optimal for the manufacturer to offer a quantity discount. We show that even without market expansion, i.e., no exclusive DOTD retailer consumers, opening the intermittent channel can leave the permanent retailer no worse‐off while increasing the manufacturer's profit. We identify the regular and discounted wholesale prices and the threshold quantity at which the manufacturer should give the discount. We also identify the optimal retail prices. We find that opening the intermittent channel increases the profit of the manufacturer, is likely to decrease the average retail price and to increase sales, and may increase the permanent retailer's profit. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 505–528, 2016     

船舶操纵模拟器立体视景系统理论、方法和实现的研究

在船舶操纵模拟器中,视景系统的立体显示为场景中物体的空间关系提供重要的视觉信息,并大大地增强了三维场景的真实感。分析了立体显示方法的原理,介绍了多通道立体显示系统所需的设备及环境,提出了基于Vega的船舶操纵模拟器的立体显示视景系统结构框架,阐述了Vega中场景初始化的方法及立体显示参数的设置,并实现了基于Vega的船舶操纵模拟器视景系统的立体显示,提高了船舶操纵模拟器视景系统的逼真度。     

基于频谱分析的飞行模拟器飞行性能验证

介绍频谱分析用于仿真系统模型验证的原理和方法,提出一种应用频谱分析进行飞行模拟器飞行性能验证的方案。结合飞行试验和仿真模型的输出数据,分别采用窗谱估计和最大熵谱估计方法对某型飞行模拟器的飞行性能进行验证,并对验证结果进行分析。结果表明,频谱分析法用于飞行模拟器飞行性能的验证是有效的,可为其他训练模拟器的性能验证提供参考。     

目标反射亮点仿真技术研究

研究了目标反射亮点的数学模型及仿真系统的硬件结构,并将目标回波亮点模型进行了简化,使之能够用于工程实现.在此基础上对用于声制导鱼雷半实物仿真系统的目标模拟器进行了设计,在试验中能够实现预定的功能.     

红外导弹制导系统的半实物仿真系统设计

对导弹系统的核心部件——制导系统进行半实物仿真是导弹系统研制中最经济和有效的手段之一。论述了红外制导系统半实物仿真系统的功用,给出了其原理框图,对其中几个关键技术:运动学方程特性的仿真建模、目标背景与对抗特性的生成技术、计算机软件和接口技术、校准设备与故障检测等的实现进行了深入地分析,并介绍了其具体的设计方案。