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51.
舰载机保障作业过程受到多种资源约束,同时可能存在突发事件的干扰。针对此特点,分析并制定干扰情况下的模型修正策略。在遗传算法中引入禁忌搜索算子改进传统遗传算法的变异操作,并通过具体实例进行仿真验证,其结果证明改进后的遗传算法在优化含干扰事件的多机保障问题时效率更高,并通过甘特图直观地反映重调度方案,为真实情况下有效处理舰载机保障过程中的干扰事件奠定理论基础。 相似文献
52.
《防务技术》2020,16(1):201-207
Three different kinds of PELE (the penetrator with lateral efficiency) were launched by ballistic artillery to impact the multi-layer spaced metal target plates. The impact velocities of the projectiles were measured by the velocity measuring system. The damage degree and process of each layer of target plate impacted by the three kinds of projectiles were analyzed. The experimental results show that all the three kinds of projectiles have the effect of expanding holes on the multi-layer spaced metal target plates. For the normal structure PELE(without layered) with tungsten alloy jacket and the radial layered PELE with tungsten alloy jacket, the diameters of holes on the second layer of plates are 3.36 times and 3.76 times of the diameter of the projectile, respectively. For radial layered PELE with W/Zr-based amorphous composite jacket, due to the large number of tungsten wires dispersed after the impact, the diameter of the holes on the four-layer spaced plates can reach 2.4 times, 3.04 times, 5.36 times and 2.68 times of the diameter of the projectile. Besides, the normal structure PELE with tungsten alloy jacket and the radial layered PELE whit tungsten alloy jacket formed a large number of fragments impact marks on the third target plate. Although the number of fragments penetrating the third target plate is not as large as that of the normal structure PELE, the area of dispersion of fragments impact craters on the third target plate is larger by the radial layered PELE. The radial layered PELE with W/Zr-based amorphous composite jacket released a lot of heat energy due to the impact of the matrix material, and formed a large area of ablation marks on the last three target plates. 相似文献
53.
《防务技术》2020,16(5):1073-1087
Because of the uncertainty and subjectivity of decision makers in the complex decision-making environment, the evaluation information of alternatives given by decision makers is often fuzzy and uncertain. As a generalization of intuitionistic fuzzy set (IFSs) and Pythagoras fuzzy set (PFSs), q-rung orthopair fuzzy set (q-ROFS) is more suitable for expressing fuzzy and uncertain information. But, in actual multiple attribute decision making (MADM) problems, the weights of DMs and attributes are always completely unknown or partly known, to date, the maximizing deviation method is a good tool to deal with such issues. Thus, combine the q-ROFS and conventional maximizing deviation method, we will study the maximizing deviation method under q-ROFSs and q-RIVOFSs in this paper. Firstly, we briefly introduce the basic concept of q-rung orthopair fuzzy sets (q-ROFSs) and q-rung interval-valued orthopair fuzzy sets (q-RIVOFSs). Then, combine the maximizing deviation method with q-rung orthopair fuzzy information, we establish two new decision making models. On this basis, the proposed models are applied to MADM problems with q-rung orthopair fuzzy information. Compared with existing methods, the effectiveness and superiority of the new model are analyzed. This method can effectively solve the MADM problem whose decision information is represented by q-rung orthopair fuzzy numbers (q-ROFNs) and whose attributes are incomplete. 相似文献
54.
《防务技术》2020,16(3):695-704
This paper is mainly on the problem of radiation interception risk control in sensor network for target tracking. Firstly, the sensor radiation interception risk is defined as the product of the interception probability and the cost caused by the interception. Secondly, the radiation interception probability model and cost model are established, based on which the calculation method of interception risk can be obtained. Thirdly, a sensor scheduling model of radiation risk control is established, taking the minimum interception risk as the objective function. Then the Hungarian algorithm is proposed to obtain sensor scheduling scheme. Finally, simulation experiments are mad to prove the effectiveness of the methods proposed in this paper, which shows that compared with the sensor radiation interception probability control method, the interception risk control method can keep the sensor scheduling scheme in low risk as well as protect sensors of importance in the sensor network. 相似文献
55.
大容量储能发电机作为脉冲电源,整流后通过逆变器向大功率脉冲负载供电。采用储能发电机直流侧并联方式工作,可以有效提高系统带载能力与可靠性。当并联运行的储能发电机转速不同时,根据转速合理分配电机释放功率可以有效提高系统工作效能,因此需要设计一种具有功率调节功能的励磁控制算法。在电压、电流双闭环控制的基础上,引入功率前馈控制,推导并求解了前馈功率与励磁电流关系以及控制参数,并根据电机初始转速设计了功率分配算法。仿真试验结果表明,功率前馈控制在励磁控制过程中起主导作用,有效分配储能电机释放功率大小,提高了励磁电流响应速度,抑制了负载功率扰动对励磁控制系统的影响。 相似文献
56.
We consider scheduling a set of jobs with deadlines to minimize the total weighted late work on a single machine, where the late work of a job is the amount of processing of the job that is scheduled after its due date and before its deadline. This is the first study on scheduling with the late work criterion under the deadline restriction. In this paper, we show that (i) the problem is unary NP‐hard even if all the jobs have a unit weight, (ii) the problem is binary NP‐hard and admits a pseudo‐polynomial‐time algorithm and a fully polynomial‐time approximation scheme if all the jobs have a common due date, and (iii) some special cases of the problem are polynomially solvable. 相似文献
57.
以维修舱空间、舱室邻接、舱室全局位置三个指标为目标函数,以满足高初稳性要求、保证船舶浮态等为约束条件,建立技术可行前提下半潜维修船功能舱室布局优化模型。通过设计贪婪取走启发式算法与规划求解相结合的两阶段算法,实现对模型的求解。以载重为5×10~4 t的半潜船体为载体进行设计,得到半潜维修船功能舱室优化布局方案。随着维修设备质量系数的增加,可行的布局方案数呈上升趋势。该方法可提高半潜维修船在功能舱室布局过程中决策的科学性。 相似文献
58.
针对传统回溯算法在求解基于知识模型的有效载荷系统功能序列规划问题中搜索效率低的问题,提出一种基于"择劣变异"(Worst Individual Mutation,WIM)策略的协同遗传算法(Co-evolutionary Genetic Algorithm,CGA)的改进算法WIM-CGA。该算法在遗传过程中采用双路线进化方案,即"择优实施标准遗传过程,择劣实施变异操作",达到提高求解精确度及搜索效率的目的。仿真结果表明,同等测试条件下,当功能规模为50,约束密度为1.0时,WIM-CGA算法在限定时间内最优解的平均精确度比优化的回溯算法提高了54.15%,比CGA算法提高了6.18%,且当所得解的精确度大于90%时,WIM-CGA算法比CGA算法的迭代次数减少了65.79%,耗时降低了48.97%,显著提高了功能序列规划的效率。 相似文献
59.
60.
基于位置信息的无线传感器网络如果完全采用无状态的方式路由,在某些拓扑结构中存在数据不可到达的缺陷,即死亡点的问题.针对这一问题,将无线传感器网络抽象为一数学模型,在此模型的基础上,给出了问题的数学描述.经分析,提出了一种基于逃离算法的详细解决方案.对算法的性能从理论上分析得出算法没有环路,是正确可行的,而仿真结果也验证了这一点,算法的时间复杂度为O(n). 相似文献