基于约束的交互式电气线路故障诊断

给出了器件的约束表示,实现了电气线路的约束网络化.分析了电气线路约束网络的特点,找出了故障树的剪节方法,提出了基于约束故障诊断的方法和步骤.     

On the generation of deep disjunctive cutting planes

In this paper we address the question of deriving deep cuts for nonconvex disjunctive programs. These problems include logical constraints which restrict the variables to at least one of a finite number of constraint sets. Based on the works of Balas. Glover, and Jeroslow, we examine the set of valid inequalities or cuts which one may derive in this context, and defining reasonable criteria to measure depth of a cut we demonstrate how one may obtain the “deepest” cut. The analysis covers the case where each constraint set in the logical statement has only one constraint and is also extended for the case where each of these constraint sets may have more than one constraint.     

基于松弛序列凸优化的轮式机器人协同轨迹规划

针对威胁环境下的多智能体协同轨迹规划问题,以轮式机器人为对象,研究了基于序列凸优化方法的协同轨迹规划方法.首先通过对轮式机器人模型的分析,给出单独轮式机器人实际物理约束,同时以状态量、控制量加权为性能指标,考虑运动学方程、避障避碰约束、个体物理性能约束、终端约束,建立多轮式机器人协同轨迹规划问题;其次,对运动学方程、避...     

On a constraint qualification in a nondifferentiable programming problem

A mathematical programming problem with an objective function containing the square root of a positive semidefinite quadratic form has been considered by Mond. In order to use a transposition theorem of Eisenberg, Mond introduces a complicated constraint qualification. In this note we give a simple geometric characterization to this constraint qualification and show that it is implied by the generalized Slater constraint qualification.     

基于遗传模拟退火算法的OFDMA系统资源分配

针对多用户OFDMA系统,提出了一种基于遗传模拟退火算法的多用户OFDMA系统资源分配策略。在资源分配时,首先假设总功率在载波间均等分配,随后根据比例速率要求确定每个用户需要的子带数,最后引入遗传模拟退火算法求解联合优化中的子带分配,在保证用户间公平性的前提下最大化系统吞吐量。仿真结果表明,该策略系统容量较大,并且近似满足了不同用户间传输速率比例性要求。     

复杂约束下的导弹作战任务规划模型和算法研究*

导弹作战任务规划是一个涉及时间、资源、质量和其他关系约束的复杂问题.首先通过定叉约束满足效用对基本约束满足模型进行了扩展,建立了导弹任务规划的约束满足优化模型.在此基础上,研究了任务规划模型求解的时间和效用传播算法,提出了基于综合效用的优化求解框架.该模型和求解框架易于解决具有多种约束因素的复杂问题,具有较好的通用性.通过定义软、硬约束效用,使得实际任务规划问题求解具有更好的灵活性.     

大椭圆停泊轨道月球探测器发射窗口运动学约束特性分析及转移轨道快速设计方法

通过分析大椭圆停泊轨道月球探测器发射窗口的运动学约束特性,给出了转移轨道运动学约束对发射窗口的影响规律,进一步明确了在该种情况下月球探测器的发射机会和增加窗口的可能性.并结合发射窗口运动学约束特性,提出了一种基于大椭圆停泊轨道的地月转移轨道快速设计方法.仿真结果验证了大椭圆停泊轨道下探测器发射窗口运动学约束特性分析的正确性,以及转移轨道设计方法的有效性.     

具有落角约束的对地攻击自适应变结构导引律

针对空对地攻击武器对地面目标的精确打击问题,提出了一种带落角约束的自适应滑模变结构末制导律。该制导律在自适应滑模导引律的基础上,引入落角约束项,可以满足制导精度和落角的双重要求。仿真结果表明,该制导律对地面活动目标的攻击既具有较高的制导精度,又可以满足落角要求,对空地精确制导武器的作战使用具有指导意义。     

某制导侵彻航弹复合制导方案设计

首先分析了着靶姿态对钻地弹侵彻的影响,并就某制导侵彻航弹要求弹着角大和射程远的特点,提出了解决方案,设计钻地航弹复合制导方案,即通过方案弹道加末端角约束比例导引律实现对钻地航弹射程和末段着靶姿态的要求。针对方案弹道设计PID控制律,提出了中末段制导方案转换条件,仿真结果表明弹药着地时具有高速且满足末端角度约束。     

具有终端约束的制导炸弹模糊变结构制导律设计

针对INS/GPS制导炸弹对地面目标的精确打击问题,提出带落角约束的模糊变结构制导律。在变结构制导律的基础上,引入终端落角约束项,应用模糊规则对所设计制导律中的变结构开关项系数增益进行在线调节。仿真结果表明,在对地面目标进行攻击时,该制导律降低变结构控制系统的抖振,同时满足制导精度和期望落角的要求,具有有效性和鲁棒性。     

Vector processing approach to constrained network problems

Modification of algorithms designed for scalar computing, to take advantage of vector processing, raises several challenges. This article presents the vectorization of the primal simplex based network algorithm and results in a 50% improvement in computational time. One of the major contributors to this improvement is the matching of the size of the pricing candidate list to the vector register size. The side constraints are relaxed into a single surrogate constraint. The single constraint network algorithm is vectorized and used as the basis for solving large-scale constrained network problems. Computational experiments are presented which illustrate the vectorization of the network code as well as the ability of the surrogate constraint approach to deal with large constrained network problems.     

On the equivalence of three approximate continuous review inventory models

This paper considers the problem of computing reorder points and order quantities for continuous review inventory systems subject to either a service level constraint or a constraint on the average fraction of time out of stock. It is demonstrated that three apparently distinct models are equivalent under these circumstances. Using this equivalence, streamlined algorithms for computed lot sizes and recorder points are developed.     

考虑弹体动态特性的机动效率约束导引律

针对考虑交会角和过载约束导引律在大机动时能量损失大的问题,提出一种考虑导弹机动效率的多约束制导律。应用最优二次型原理推导出考虑一阶弹体延迟的时变导引系数闭环次优制导形式,将导弹机动时刻阻力系数引入时变权系数,并通过迭代确定机动效率约束边界。将时变约束表示成剩余时间与弹体延迟时间的函数,代入制导指令,进行弹道仿真。结果表明,对于常值与机动目标,文中制导律与过载约束导引律同只考虑交会角约束的导引律相比,对目标均能实现末端弹道成型要求,而考虑机动效率的制导指令分配更为合理,在避免指令加速度饱和的同时有效降低了拦截末端速度损耗,提高制导精度与毁伤效果。且该制导律中时变权系数无须配平求解,在保证精度的同时极大地提高了迭代速度。     

Geometric programming with multiplicative slack variables

A posynomial geometric programming problem formulated so that the number of objective function terms is equal to the number of primal variables will have a zero degree of difficulty when augmented by multiplying each constraint term by a slack variable and including a surrogate constraint composed of the product of the slack variables, each raised to an undetermined negative exponent or surrogate multiplier. It is assumed that the original problem is canonical. The exponents in the constraint on the product of the slack variables must be estimated so that the associated solution to the augmented problem, obtained immediately, also solves the original problem. An iterative search procedure for finding the required exponents, thus solving the original problem, is described. The search procedure has proven quite efficient, often requiring only two or three iterations per degree of difficulty of the original problem. At each iteration the well-known procedure for solving a geometric programming problem with a zero degree of difficulty is used and so computations are simple. The solution generated at each iteration is optimal for a problem which differs from the original problem only in the values of some of the constraint coefficients, so intermediate solutions provide useful information.     

Component commonality in assemble-to-order systems: Models and properties

This article presents a general multiperiod model of an assemble-to-order system with component commonality and proves that its solution is myopic. The model is then endowed with a capacity or storage constraint, and the resulting behavior of optimal policies is investigated. Interestingly, with such constraint, the optimal stocks of product-specific components can be lower in an assemble-to-order system than in a corresponding make-to-stock one, a behavior that is impossible in an unconstrained model.     

两跳OFDM译码转发中继系统的功率分配研究

分析了系统总功率约束和各节点独立功率约束条件下的中继信道,提出了以最大化系统容量为准则的两跳中继系统联合子载波配对和功率优化分配算法。算法先进行子载波配对,然后选出一组信道增益最大的子载波进行平均功率分配,最后通过迭代得到功率分配结果。为了进一步降低系统复杂度,我们利用相邻子载波之间的相关性,用若干相邻子载波组成一个等效子信道。仿真结果表明,所提算法可以在大大降低反馈量的情况下达到和注水功率分配几乎相同的系统容量。     

多约束条件下无人机航路规划动态评价方法

针对多约束条件的无人机航路规划评价方法缺乏合理性和动态特性的问题,提出了基于无人机六自由度模型的飞行仿真动态评价方法。分析了无人机航路规划的约束条件和影响航路评价的因素,基于某型无人机六自由度飞行动力学模型和飞行控制系统模型建立了无人机飞行仿真系统模型,将航路规划与评价进行有机结合进而进行航路评价方法软件的设计,通过对无人机沿规划航路的仿真飞行参数进行动态特性分析,以更接近真实情况的仿真手段对多约束条件下的航路规划效果进行评价。结果表明,该方法形象直观的实现了对无人机规划航路的动态综合评价,满足工程需求。     

War as a System: A Three-Stage Model for the Development of Clausewitz’s Thinking on Military Conflict and Its Constraints

This article presents a new model for the development of Carl von Clausewitz’s thinking on the factors that constrain warfare. The model posits three stages in his thinking that are determined by two system theoretic dimensions. The three stages are friction as a constraint on the effectiveness of the execution of military plans on paper, suspension as a constraint on the intensity of military action and political objectives as a constraint on military objectives. The two dimensions consist of an interactive perspective in the form of causal feedback loops and a holistic perspective in the form of a political system that forms the context of the military subsystem.     

螺旋轮式管道检测机器人越障性能研究

建立了一种螺旋轮式管道检测机器人驱动系统的三维模型,对驱动系统通过凸台和三通的能力进行了动力学分析。研究了预紧弹簧刚度和预紧力对螺旋轮过凸台能力的影响,讨论了过三通时的几何约束和动力学约束条件,并通过算例分析,验证了模型的正确性。     

More ado about economic order quantities (EOQ)

This paper is concerned with the determination of explicit expressions for economic order quantities and reorder levels, such that the cost of ordering and holding inventory is minimized for specific backorder constraints. Holding costs are applied either to inventory position or on-hand inventory, and the backorder constraint is considered in terms of the total number of backorders per year or the average number of backorders at any point in time. Through the substitution of a new probability density function in place of the normal p.d.f., explicit expressions are determined for the economic order quantities and the reorder points. The resulting economic order quantities are independent of all backorder constraints. It is also concluded that under certain conditions, the minimization of ordering costs and inventory holding costs (applied to inventory position), subject to a backorder constraint, is equivalent in terms of reorder levels to minimization of the safety level dollar investment subject to the same backorder constraint.