Performance evaluation and optimization design of photoelectric pyrometer detection optical system

The measurement and control of high temperature play very important roles in national defense, military, scientific experiments, industrial and agricultural production. Photoelectric pyrometer is one of the important radiation thermometers for non-contact temperature measurement. It has an important application in the field of high temperature measurement, and its performance directly affects the accuracy of temperature measurement. By improving the design of the detection optical system of the photoelectric pyrometer, the imaging performance of the photoelectric pyrometer can be improved effectively, and the temperature measurement accuracy can be improved. In this paper, the temperature measurement principle of photoelectric pyrometer, the working principle of the detection optical system and the composition of the system are introduced. The optical components that affect the imaging of the optical system of the photoelectric pyrometer are analyzed. The optical pyrometer detection optical system is simulated by ZEMAX software, based on the analysis results, the Modulation Transfer Function (MTF) and the spot Diagram are used as the main evaluation criteria to optimize the design of the objective lens of the photoelectric pyrometer detection optical system. The imaging performance of the photoelectric pyrometer detection optical system and the accuracy of temperature measurement of the photoelectric pyrometer are improved by optimization design of the detection optical system.     

Application of Markov renewal theory and semi-Markov decision processes in maintenance modeling and optimization of multi-unit systems

In this paper, a condition-based maintenance model for a multi-unit production system is proposed and analyzed using Markov renewal theory. The units of the system are subject to gradual deterioration, and the gradual deterioration process of each unit is described by a three-state continuous time homogeneous Markov chain with two working states and a failure state. The production rate of the system is influenced by the deterioration process and the demand is constant. The states of the units are observable through regular inspections and the decision to perform maintenance depends on the number of units in each state. The objective is to obtain the steady-state characteristics and the formula for the long-run average cost for the controlled system. The optimal policy is obtained using a dynamic programming algorithm. The result is validated using a semi-Markov decision process formulation and the policy iteration algorithm. Moreover, an analytical expression is obtained for the calculation of the mean time to initiate maintenance using the first passage time theory.     

On efficient algorithms for finding efficient salvo policies

We consider the salvo policy problem, in which there are k moments, called salvos, at which we can fire multiple missiles simultaneously at an incoming object. Each salvo is characterized by a probability p_i: the hit probability of a single missile. After each salvo, we can assess whether the incoming object is still active. If it is, we fire the missiles assigned to the next salvo. In the salvo policy problem, the goal is to assign at most n missiles to salvos in order to minimize the expected number of missiles used. We consider three problem versions. In Gould's version, we have to assign all n missiles to salvos. In the Big Bomb version, a cost of B is incurred when all salvo's are unsuccessful. Finally, we consider the Quota version in which the kill probability should exceed some quota Q. We discuss the computational complexity and the approximability of these problem versions. In particular, we show that Gould's version and the Big Bomb version admit pseudopolynomial time exact algorithms and fully polynomial time approximation schemes. We also present an iterative approximation algorithm for the Quota version, and show that a related problem is NP-complete.     

OFDM系统中深度神经网络指导的IQ不平衡补偿算法

正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)是现代移动通信中一项重要的物理层通信技术,并且OFDM系统要求子载波间严格正交。然而,在实际系统中,振荡器和滤波器等器件的非理想特性会导致同相正交(In-phase and Quadrature-phase,IQ)不平衡,从而破坏子载波的正交性,严重影响OFDM系统的性能。通过研究IQ不平衡对OFDM系统的影响,提出了一种并联深度神经网络架构下的IQ不平衡补偿算法。该算法利用了深度神经网络不依赖于模型的特点,直接从接收到的频域信号恢复原输入信号的二进制序列,并利用干扰信号来自镜像子载波的先验知识来初始化模型驱动的神经网络,加快其网络优化的收敛速度。仿真结果表明,该算法能有效地补偿IQ不平衡失真,并且在幅度和相位失真的补偿上,其性能都优于传统的基于导频的最小二乘补偿算法,证明了深度学习方法解决物理层问题的优越性。     

改进BAS-TIMS算法在空战机动决策中的应用

针对当前空战机动决策精确度低、实时性差的缺点,对天牛须搜索-战术免疫机动系统(Beetle Antennae Search-Tactical Immune Maneuver System, BAS-TIMS)算法进行改进,并应用于空战机动决策中。增加左爬升、右爬升、左俯冲、右俯冲4种机动,对传统的机动策略库进行扩充,设计了11种基本机动策略并给出了相应的控制方法。基于距离、高度、速度、角度和战机性能优势函数,利用非参量法构造战机机动决策综合优势函数。针对天牛须搜索算法在全局搜索和收敛速度上存在的缺陷,引入蒙特卡洛概率迭代的方法对算法进行改进,并和战术免疫机动系统进行融合,将改进的BAS-TIMS算法用于空战机动决策。设计算例进行仿真分析,并将结果和博弈论法、改进共生生物免疫进化算法、传统BAS算法和传统TIMS模型的计算结果进行对比,验证所提算法的有效性。仿真结果表明:改进BAS-TIMS算法在空战机动决策的收敛精度、收敛速度和全局搜索能力上更加具有优势。     

创新人才军民融合培养体系及其构建

创新人才军民融合培养构成人才强国战略、创新驱动发展战略和军民融合发展战略的交汇点。创新人才是战略资源,军民融合为创新人才培养提供了一条全新路径。作为一项系统工程,创新人才军民融合培养包括创新人才军民融合培养主体系统、创新人才军民融合培养客体系统、创新人才军民融合培养方案系统、创新人才军民融合培养资源系统、创新人才军民融合培养制度系统、创新人才军民融合培养考评系统,在系统构建过程中需加大统筹协调、投入保障、政策倾斜、法治保障、合理使用力度,注重体系推进。     

军民融合产业概念及范畴研究

军民融合产业概念及范畴不明确一直是困扰决策部门和研究部门的问题,影响了军民融合发展的顺利推进。本文在梳理总结军民融合产业概念及范畴的研究现状以及政府文件表述的基础上,认为军民融合作为一种发展模式,定义军民融合产业概念并非易事,但出于当前工作要求,需要相关管理部门整合力量,加强研究,尽快明确军民融合产业概念和范畴,构建科学合理的军民融合产业统计体系。     

采用PWPF调节器的再入飞行器最优控制分配方法

针对具有反作用控制系统(Reaction Control System,RCS)和气动舵两类控制机构的再入飞行器,提出一种基于脉宽脉频(Pulse-Width Pulse-Frequency,PWPF)调节器的最优控制分配方法。将RCS的输入信号转化为连续变化量,RCS与气动舵的控制分配问题被描述为二次规划问题,并采用有效集方法对其求解。采用离散法和PWPF调节器将优化结果转化为RCS的开关机状态。与混合整数规划问题相比,连续二次规划问题更容易求解,计算速度更快。通过对二次规划问题的重构,该算法能有效地应对故障情况。     

机载航电系统射频隐身性能多域联合评估方法

针对机载航电系统自身辐射源特性,提出一种不依赖敌方探测设备的机载航电系统射频隐身性能评估方法。分析机载航电系统设备在极化域、波形域、能量域中影响射频隐身性能的因素,构建极化域、能量域、波形域射频隐身指标,打破常规的"辐射-接收"模型的隐身性能评估方法,建立基于机载航电系统自身辐射信号工作状态和工作参数的射频隐身定量评估方法。对机载雷达系统进行仿真评估,结果表明,该评估方法能正确反映机载雷达系统的射频隐身性能。     

防空兵指挥决策系统及其运行环境的影响

决策者、决策辅助人员和指挥决策信息系统是部队指挥决策系统的基本组成部分,防空兵指挥自动化和决策支持系统则是指挥决策信息系统的一部分,环境因素和决策信息是影响防空兵指挥决策系统的重要因素.从系统的观点阐述了防空兵指挥决策系统与内外环境因素的关系,提出在新技术条件下,系统信息是防空兵指挥决策系统的又一组成要素.从这个观点出发,可以准确、全面地了解和分析系统环境因素对防空兵指挥决策系统影响,最终达到提高防空兵指挥决策效能的目的.