多目标资源受限项目调度的多种群蚁群算法

为实现资源受限项目调度的多目标优化,通过改进传统蚁群算法,提出适用于多目标优化的多种群蚁群算法.该算法基于串行进度生成机制,每个蚁群具有各自的目标函数、与目标函数相匹配的不同搜索策略以及各自的信息素更新机制.各蚁群独立进行搜索决策,但各蚁群之间存在信息素的相互作用,从而实现加速搜索.针对多目标资源受限项目调度问题设计新的精英策略.在目标规划基础上构造一系列多目标项目调度算例,经系统测试表明,所提出的多种群蚁群算法能够有效优化资源受限项目的资源配置,实现多目标优化.     

遗传余代数与二次型

给出1类重要的遗传余代数——正规的广义路余代数,在余代数上定义了3种二次型,证明了在Gabriel箭图是局部有限的遗传余代数上定义的这3种二次型一致。     

刚体动力学初值问题的拟变分原理及其应用

随着科学技术的发展,对刚体动力学提出新的要求.应用变积方法,建立了刚体动力学初值问题的拟变分原理.推导出刚体动力学初值问题的拟变分原理的拟驻值条件.建立了刚体动力学初值问题的广义拟变分原理,说明了应用广义拟变分原理求得问题的解析解和数值解的途径.借助算例说明了应用变分方法来研究刚体动力学初值问题的优越性.     

Equilibrium equations for nonlinear buckling analysis of drill-strings in 3D curved well-bores

With the development of drilling technology, the oil/gas well has evolved from its early vertical straight form to the inclined, horizontal, plane curved, or even 3D curved well-bore. Understanding of the buck-ling behavior of a drill-string in a well-bore is crucial for the success of a drilling operation. Therefore, equilibrium equations for analyzing the buckling behavior of a drill-string in a 3D curved well-bore are required. Based on Love’s equilibrium equations for a curved and twisted rod in space, ...     

由平方剩余差集与差集偶构造二元ZCZ序列偶集

提出了一种利用平方剩余差集(4t-1,2t-1,t-1) DS和差集偶(N,p,q,e,λ) DS
P构造二元零相关区(ZCZ)序列偶集的方法. 由平方剩余差集获得其二元特征序列,并由差集
偶获得其特征二元序列偶,将二者进行交织构造生成一类新的二元ZCZ序列偶集. 该方法解
决了现有二元ZCZ序列偶集构造中含有少量非二元元素的问题,通过选择适当的差集偶可使构造的二元ZCZ序列偶集在失配滤波检测中获
得较高的能量效率,从而提高了通信性能.     

基于区域结构特征的城区LiDAR数据快速分类

机载激光雷达能够及时准确地获取大量具有精确三维位置信息的三维点云数据,在数字城市、森林防火、智能交通等领域有着广泛的应用。城市中心区域的三维点云数据往往会因为高大树木或植被的遮挡,造成建筑物等人造目标识别特别困难。本文通过直接的二次多项式拟合方式提取高大树木等植被与建筑物目标典型局部区域的区域信息,构建区域目标敏感的结构特征,进而,通过模糊逻辑即可完成三维点云数据的建筑物目标敏感的分类任务。实验结果表明,该方法能够快速有效地实现较大尺度范围内LiDAR点云数据的分类,具有较好的应用前景和推广能力。     

Guaranteeing performance for uncertain nonlinear systems with bounded state constraint and mismatching condition

The control design problem for the uncertain nonlinear system with bounded state constraint and mismatching condition is considered in this paper. The uncertainty in the system, which may be due to unknown system parameters and external disturbance, is nonlinear and time‐varying. The state of the system is constrained to be bounded. The system does not satisfy the (global) matching condition. A creative one‐to‐one state transformation is proposed by converting the bounded states into the unbounded ones. A step‐by‐step state transformation is proposed to convert the mismatched system into a matched system. The robust control is then proposed based on the transformed system. The control is demonstrated to be able to guarantee the uniform boundedness and uniform ultimate boundedness of the system in the presence of uncertainty, while the state constraint can be always guaranteed.     

边界约束对弯曲-伸展元三轴波速试验的影响

利用弯曲-伸展元开展干砂小应变剪切波试验和除气水压缩波试验,研究了三轴试样的不同约束边界对弯曲-伸展元量测剪切波速和压缩波速的影响,并对波速试验结果进行分析。研究结果表明:以干砂为试验对象的剪切波速试验结果介于砂土中剪切波速与边界材料的剪切波速之间,受到约束边界的材质、长度和壁厚的显著影响;而以除气水为试验对象的压缩波速试验结果受样品约束边界的影响较小。在不同约束材质下,剪切波在干砂中的传播速度与约束材料的刚度有关,材料的刚度越小对干砂剪切波速测试结果影响越小。弯曲-伸展元激发频率的相关性与边界约束无关,只与测试材料有关。研究成果有助于获取准确的弯曲-伸展元波速试验结果。     

Cooperative Multi-Agent Reinforcement Learning with Constraint-Reduced DCOP

Cooperative multi-agent reinforcement learning (MARL) is an important topic in the field of artificial intelligence,in which distributed constraint optimization (DCOP) algorithms have been widely used to coordinate the actions of multiple agents.However,dense communication among agents affects the practicability of DCOP algorithms.In this paper,we propose a novel DCOP algorithm dealing with the previous DCOP algorithms' communication problem by reducing constraints.The contributions of this paper are primarily threefold:① It is proved that removing constraints can effectively reduce the communication burden of DCOP algorithms.② An criterion is provided to identify insignificant constraints whose elimination doesn't have a great impact on the performance of the whole system.③ A constraint-reduced DCOP algorithm is proposed by adopting a variant of spectral clustering algorithm to detect and eliminate the insignificant constraints.Our algorithm reduces the communication burdern of the benchmark DCOP algorithm while keeping its overall performance unaffected.The performance of constraint-reduced DCOP algorithm is evaluated on four configurations of cooperative sensor networks.The effectiveness of communication reduction is also verified by comparisons between the constraint-reduced DCOP and the benchmark DCOP.