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Branch and Bound Algorithm for Globally Solving Minimax Linear Fractional Programming
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作者 WANG Hui-man SHEN Pei-ping LIANG Yu-xin 《Chinese Quarterly Journal of Mathematics》 2024年第4期388-398,共11页
In this paper,we study the minimax linear fractional programming problem on a non-empty bounded set,called problem(MLFP),and we design a branch and bound algorithm to find a globally optimal solution of(MLFP).Firstly,... In this paper,we study the minimax linear fractional programming problem on a non-empty bounded set,called problem(MLFP),and we design a branch and bound algorithm to find a globally optimal solution of(MLFP).Firstly,we convert the problem(MLFP)to a problem(EP2)that is equivalent to it.Secondly,by applying the convex relaxation technique to problem(EP2),a convex quadratic relaxation problem(CQRP)is obtained.Then,the overall framework of the algorithm is given and its convergence is proved,the worst-case iteration number is also estimated.Finally,experimental data are listed to illustrate the effectiveness of the algorithm. 展开更多
关键词 Minimax linear fractional programming Global optimal solution Branch and bound
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MULTI-OBJECTIVE PROGRAMMING FOR AIRPORT GATE REASSIGNMENT
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作者 李军会 陈欣 朱金福 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第2期209-215,共7页
To improve the efficiency of gate reassignment and optimize the plan of gate reassignment,the concept of disruption management is introduced,and a multi-objective programming model for airport gate reassignment is pro... To improve the efficiency of gate reassignment and optimize the plan of gate reassignment,the concept of disruption management is introduced,and a multi-objective programming model for airport gate reassignment is proposed.Considering the interests of passengers and the airport,the model minimizes the total flight delay,the total passengers′walking distance and the number of flights reassigned to other gates different from the planned ones.According to the characteristics of the gate reassignment,the model is simplified.As the multi-objective programming model is hard to reach the optimal solutions simultaneously,a threshold of satisfactory solutions of the model is set.Then a simulated annealing algorithm is designed for the model.Case studies show that the model decreases the total flight delay to the satisfactory solutions,and minimizes the total passengers′walking distance.The least change of planned assignment is also reached.The results achieve the goals of disruption management.Therefore,the model is verified to be effective. 展开更多
关键词 gate assignment multi-objective programming simulated annealing algorithm disruption management
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An Exact Virtual Network Embedding Algorithm Based on Integer Linear Programming for Virtual Network Request with Location Constraint 被引量:3
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作者 Zeheng Yang Yongan Guo 《China Communications》 SCIE CSCD 2016年第8期177-183,共7页
Network virtualization is known as a promising technology to tackle the ossification of current Internet and will play an important role in the future network area. Virtual network embedding(VNE) is a key issue in net... Network virtualization is known as a promising technology to tackle the ossification of current Internet and will play an important role in the future network area. Virtual network embedding(VNE) is a key issue in network virtualization. VNE is NP-hard and former VNE algorithms are mostly heuristic in the literature.VNE exact algorithms have been developed in recent years. However, the constraints of exact VNE are only node capacity and link bandwidth.Based on these, this paper presents an exact VNE algorithm, ILP-LC, which is based on Integer Linear Programming(ILP), for embedding virtual network request with location constraints. This novel algorithm is aiming at mapping virtual network request(VNR) successfully as many as possible and consuming less substrate resources.The topology of each VNR is randomly generated by Waxman model. Simulation results show that the proposed ILP-LC algorithm outperforms the typical heuristic algorithms in terms of the VNR acceptance ratio, at least 15%. 展开更多
关键词 network virtualization virtual network embedding exact VNE algorithm integer linear programming location constraint VNR acceptance ratio
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Efficient Algorithm for K-Barrier Coverage Based on Integer Linear Programming 被引量:15
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作者 Yanhua Zhang Xingming Sun Baowei Wang 《China Communications》 SCIE CSCD 2016年第7期16-23,共8页
Barrier coverage of wireless sensor networks is an important issue in the detection of intruders who are attempting to cross a region of interest.However,in certain applications,barrier coverage cannot be satisfied af... Barrier coverage of wireless sensor networks is an important issue in the detection of intruders who are attempting to cross a region of interest.However,in certain applications,barrier coverage cannot be satisfied after random deployment.In this paper,we study how mobile sensors can be efficiently relocated to achieve k-barrier coverage.In particular,two problems are studied:relocation of sensors with minimum number of mobile sensors and formation of k-barrier coverage with minimum energy cost.These two problems were formulated as 0–1 integer linear programming(ILP).The formulation is computationally intractable because of integrality and complicated constraints.Therefore,we relax the integrality and complicated constraints of the formulation and construct a special model known as RELAX-RSMN with a totally unimodular constraint coefficient matrix to solve the relaxed 0–1 ILP rapidly through linear programming.Theoretical analysis and simulation were performed to verify the effectiveness of our approach. 展开更多
关键词 k-barrier coverage linear programming wireless sensor networks
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The Optimal Conditions of the Linear Fractional Programming Problem with Constraint 被引量:1
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作者 SUN Jian-she YE Liu-qing 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期553-556,共4页
In this article,the authors discuss the optimal conditions of the linear fractionalprogramming problem and prove that a locally optional solution is a globally optional solution and the locally optimal solution can be... In this article,the authors discuss the optimal conditions of the linear fractionalprogramming problem and prove that a locally optional solution is a globally optional solution and the locally optimal solution can be attained at a basic feasible solution withconstraint condition. 展开更多
关键词 linear fractional programming problem pseudo-convex function optimal solution CONSTRAINT
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A new heuristic algorithm for general integer linear programming problems 被引量:1
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作者 高培旺 《Journal of Chongqing University》 CAS 2006年第3期170-174,共5页
A new heuristic algorithm is proposed for solving general integer linear programming problems. In the algorithm, the objective function hyperplane is used as a cutting plane, and then by introducing a special set of a... A new heuristic algorithm is proposed for solving general integer linear programming problems. In the algorithm, the objective function hyperplane is used as a cutting plane, and then by introducing a special set of assistant sets, an efficient heuristic search for the solution to the integer linear program is carried out in the sets on the objective function hyperplane. A simple numerical example shows that the algorithm is efficient for some problems, and therefore, of practical interest. 展开更多
关键词 integer linear programming objective function hyperplane cutting plane heuristic algorithm
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Polynomial Complexity Bounds of Mehrotra-type Predictor-corrector Algorithms for Linear Programming over Symmetric Cones
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作者 刘长河 尚有林 李振国 《Chinese Quarterly Journal of Mathematics》 2015年第4期475-494,共20页
We establish polynomial complexity corrector algorithms for linear programming over bounds of the Mehrotra-type predictor- symmetric cones. We first slightly modify the maximum step size in the predictor step of the s... We establish polynomial complexity corrector algorithms for linear programming over bounds of the Mehrotra-type predictor- symmetric cones. We first slightly modify the maximum step size in the predictor step of the safeguard based Mehrotra-type algorithm for linear programming, that was proposed by Salahi et al. Then, using the machinery of Euclidean Jordan algebras, we extend the modified algorithm to symmetric cones. Based on the Nesterov-Todd direction, we obtain O(r log ε1) iteration complexity bound of this algorithm, where r is the rank of the Jordan algebras and ε is the required precision. We also present a new variant of Mehrotra-type algorithm using a new adaptive updating scheme of centering parameter and show that this algorithm enjoys the same order of complexity bound as the safeguard algorithm. We illustrate the numerical behaviour of the methods on some small examples. 展开更多
关键词 linear programming symmetric cone Euclidean Jordan algebra interior-point methods Mehrotra-type algorithm polynomial complexity
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Design of S-band photoinjector with high bunch charge and low emittance based on multi-objective genetic algorithm 被引量:1
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作者 Ze-Yi Dai Yuan-Cun Nie +9 位作者 Zi Hui Lan-Xin Liu Zi-Shuo Liu Jian-Hua Zhong Jia-Bao Guan Ji-Ke Wang Yuan Chen Ye Zou Hao-Hu Li Jian-Hua He 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第3期93-105,共13页
High-brightness electron beams are required to drive LINAC-based free-electron lasers(FELs)and storage-ring-based synchrotron radiation light sources.The bunch charge and RMS bunch length at the exit of the LINAC play... High-brightness electron beams are required to drive LINAC-based free-electron lasers(FELs)and storage-ring-based synchrotron radiation light sources.The bunch charge and RMS bunch length at the exit of the LINAC play a crucial role in the peak current;the minimum transverse emittance is mainly determined by the injector of the LINAC.Thus,a photoin-jector with a high bunch charge and low emittance that can simultaneously provide high-quality beams for 4th generation synchrotron radiation sources and FELs is desirable.The design of a 1.6-cell S-band 2998-MHz RF gun and beam dynamics optimization of a relevant beamline are presented in this paper.Beam dynamics simulations were performed by combining ASTRA and the multi-objective genetic algorithm NSGA II.The effects of the laser pulse shape,half-cell length of the RF gun,and RF parameters on the output beam quality were analyzed and compared.The normalized transverse emittance was optimized to be as low as 0.65 and 0.92 mm·mrad when the bunch charge was as high as 1 and 2 nC,respectively.Finally,the beam stability properties of the photoinjector,considering misalignment and RF jitter,were simulated and analyzed. 展开更多
关键词 Electron linear accelerator PHOTOINJECTOR Beam dynamics multi-objective genetic algorithm
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A Tabu Search Algorithm for Quadratic 0-1 Programming Problem 被引量:2
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作者 周贤伟 王远允 +1 位作者 田新现 郭瑞强 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期98-102, ,共5页
In this paper,quadratic 0-1 programming problem (I) is considered, in terms of its features quadratic 0-1 programming problem is solved by linear approxity heurstic algrothm and a developed tabu search ahgrothm .
关键词 Tabu search linear approximate quaratic 0-1 programming
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Improved Group Fuzzy Preference Programming Method Based on Fuzzy Random Theory
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作者 黄礼健 吴祈宗 《Journal of Beijing Institute of Technology》 EI CAS 2007年第2期237-242,共6页
A new prioritization method in the analytic hierarchy process (AHP), which improves the group fuzzy preference programming (GFPP) method, is proposed. The fuzzy random theory is applied in the new prioritization m... A new prioritization method in the analytic hierarchy process (AHP), which improves the group fuzzy preference programming (GFPP) method, is proposed. The fuzzy random theory is applied in the new prioritization method. By modifying the principle of decision making implied in the GFPP method, the improved group fuzzy preference programming (IGFPP) method is formulated as a fuzzy linear programming problem to maximize the average degree of the group satisfaction with all possible group priority vectors. The IGFPP method inherits the advantages of the GFPP method, and solves the weighting trouble existed in the GFPP method. Numerical tests indicate that the IGFPP method performs more effectively than the GFPP method in the case of very contradictive comparison judgments from decision makers. 展开更多
关键词 group decision-making analytic hierarchy process (AHP) fuzzy linear programming fuzzy random variable
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Nonconvex Quadratic Programming Method for k-Coloring Problem:Algorithm and Computation
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作者 Cao Jiaming(Department of Transportation Engineering) ,Southwest Jiaotong University,Chengdu 610031, China 《Journal of Modern Transportation》 1994年第2期138-145,共8页
In this paper, we consider the socalled k-coloring problem in general case.Firstly, a special quadratic 0-1 programming is constructed to formulate k-coloring problem. Secondly, by use of the equivalence between above... In this paper, we consider the socalled k-coloring problem in general case.Firstly, a special quadratic 0-1 programming is constructed to formulate k-coloring problem. Secondly, by use of the equivalence between above quadratic0-1 programming and its relaxed problem, k-coloring problem is converted intoa class of (continuous) nonconvex quadratic programs, and several theoreticresults are also introduced. Thirdly, linear programming approximate algorithmis quoted and verified for this class of nonconvex quadratic programs. Finally,examining problems which are used to test the algorithm are constructed andsufficient computation experiments are reported. 展开更多
关键词 k-coloring problem quadratic 0-1 programming relaxed equivalence nonconvex quadratic programming linear programming approximatealgorithm
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基于时间窗口的时间敏感网络流量调度方法
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作者 李超 李红硕 +2 位作者 董哲 史运涛 李文昊 《电光与控制》 北大核心 2025年第4期77-81,共5页
时间敏感网络是一种新型确定性网络,流量调度作为其核心机制,主要通过门控列表保证时间触发流传输的服务质量。然而,以帧为对象进行门控调度设计时,需要计算每一帧的具体时隙分配,存在计算复杂度过高的问题。为此,针对时隙配置求解复杂... 时间敏感网络是一种新型确定性网络,流量调度作为其核心机制,主要通过门控列表保证时间触发流传输的服务质量。然而,以帧为对象进行门控调度设计时,需要计算每一帧的具体时隙分配,存在计算复杂度过高的问题。为此,针对时隙配置求解复杂的问题,将以帧为调度对象改进为以时间窗口为调度对象,基于时间窗口设计了整数线性规划调度方法,并使用Gurobi优化器得出结果。仿真实验表明:提出的调度方法在保证时间触发流的流量特性基础上有效降低了计算复杂度,与以帧为对象的调度方法相比,端到端总时延降低了约6%,求解时间减少了约41%。 展开更多
关键词 时间敏感网络 流量调度 门控列表 时间窗口 整数线性规划
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路口混合放行下的干线红波带宽最小优化模型
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作者 张鹏 吴照杰 +1 位作者 孙超 李文权 《交通运输系统工程与信息》 北大核心 2025年第2期293-303,共11页
现有干道协调控制方法主要是追求更大绿波带宽,但是由此产生的附加红波带对协调控制效果的影响没有引起足够的重视。为此,本文建立基于交叉口混合放行的干线红波带宽最小化优化模型。模型以干线直行路径及左转路径红波带宽占周期比值加... 现有干道协调控制方法主要是追求更大绿波带宽,但是由此产生的附加红波带对协调控制效果的影响没有引起足够的重视。为此,本文建立基于交叉口混合放行的干线红波带宽最小化优化模型。模型以干线直行路径及左转路径红波带宽占周期比值加权之和最小为目标函数,采用NEMA(National Electrical Manufacturers Association)双环相位和单独放行相位两种放行方式,并给出两种放行方式统一的内部相位差线性计算公式。任意交叉口均可指定放行方式,亦可自由选择。该模型采用整数线性规划方法,确保获得最优解。以苏州市松陵大道的5个连续交叉口实例进行分析。结果表明:相较于Multiband、Pband和All-direction优化方案,本文模型有效减少了干线直行和左转车辆平均延误时间与停车次数,取得较优的干线绿波协调控制效果。 展开更多
关键词 城市交通 干线协调 整数线性规划 红波带 单独放行 NEMA双环
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镇级可再生能源多能互补系统优化配置与调度探索
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作者 葛文超 任洪波 +2 位作者 朱跃钊 杨谋存 陈海军 《太阳能学报》 北大核心 2025年第3期168-176,共9页
在基于生物质能的可再生能源多能互补系统经济性优化分析的基础上,优化改进电网补充以及就地消纳模型并利用LINGO求解,以此探讨其对系统的配置调度以及经济性影响。结果表明:在就地消纳基础上限制电网补充时段,系统风光相对装机比例将增... 在基于生物质能的可再生能源多能互补系统经济性优化分析的基础上,优化改进电网补充以及就地消纳模型并利用LINGO求解,以此探讨其对系统的配置调度以及经济性影响。结果表明:在就地消纳基础上限制电网补充时段,系统风光相对装机比例将增大27.16个百分点,生物质利用单元相对装机比例降低23.09个百分点;在第一用电低谷期和高峰期上述方案会更优先使用风力发电,减少对电网的冲击;在第二用电低谷期风光有较多富余,富余电量优先用于储电,此外尚有约15%进行就地消纳;在第二用电高峰期,以光伏发电主导,生物质能和蓄电池辅助,不足部分由电网补充。相比仅引入就地消纳,该方案系统年运行费用降低32.5%,碳排放量降低39.1%,投资回收年限由8.29 a降至7.38 a。 展开更多
关键词 可再生能源 多能互补 线性规划 容量配置 优化调度 储能
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铁路编组站到发场技术作业计划编制优化方法研究
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作者 向江海 赵军 +1 位作者 张思宇 彭其渊 《铁道学报》 北大核心 2025年第2期11-23,共13页
铁路编组站到发场技术作业计划是指为到发场内各项行车和调车作业指定开始时刻、占用进路和站线,使得所有作业安全和高效地完成。基于“工作”“活动”“活动对”概念刻画到发场内各项技术作业,并分析其对线路资源的占用过程。以最小化... 铁路编组站到发场技术作业计划是指为到发场内各项行车和调车作业指定开始时刻、占用进路和站线,使得所有作业安全和高效地完成。基于“工作”“活动”“活动对”概念刻画到发场内各项技术作业,并分析其对线路资源的占用过程。以最小化总加权工作偏移时间为目标,考虑作业间时空一致性、轨道区段占用和站线占用约束,构建整数线性规划模型,提出基于资源视角的轨道区段占用约束和基于扩展时间一致性活动对的资源占用约束削减两项策略加强模型。以某编组站到达场为例构造一组切实例子验证所提出方法的有效性,结果显示提出的针对资源占用约束的建模技术显著优于既有技术,所提出方法能够快速获取一个阶段内的高质量技术作业计划。 展开更多
关键词 编组站 阶段计划 技术作业计划 整数线性规划 进路冲突疏解
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基于DDPG-LQR的高超声速飞行器时间协同再入制导
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作者 宋志飞 吉月辉 +2 位作者 宋雨 刘俊杰 高强 《导弹与航天运载技术(中英文)》 北大核心 2025年第1期57-64,共8页
针对多高超声速飞行器协同作战的特点,提出一种基于深度策略性梯度和线性二次型调节器(Deep Deterministic Policy Gradient-Linear Quadratic Regulator,DDPG-LQR)的时间协同再入制导方案。首先,采用序列凸优化方法生成满足多个约束的... 针对多高超声速飞行器协同作战的特点,提出一种基于深度策略性梯度和线性二次型调节器(Deep Deterministic Policy Gradient-Linear Quadratic Regulator,DDPG-LQR)的时间协同再入制导方案。首先,采用序列凸优化方法生成满足多个约束的时间协同再入轨迹及其相应的稳态控制量,并且采用Radau伪谱法离散运动学方程,以提高轨迹优化离散精度。其次,采用线性二次型调节器(Linear Quadratic Regulator,LQR)跟踪时间协同再入轨迹。为了提高协同制导精度和制导效果,采用深度策略性梯度(Deep Deterministic Policy Gradient,DDPG)在线优化LQR的权重矩阵系数。在DDPG算法中,通过引入合适的奖励函数来提高算法的优化性能。仿真结果表明,在初始状态误差和不确定性的情况下,通过与传统的LQR控制器相比,本文所提出的协同制导方案具有更好的协同制导精度和制导效果。 展开更多
关键词 多高超声速飞行器 协同制导 序列凸优化 深度策略性梯度 线性二次型调节器
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考虑存车条件的动车组交路计划优化方法
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作者 牛家鑫 赵鹏 +2 位作者 乔珂 张璞 魏利亨 《铁道学报》 北大核心 2025年第1期11-20,共10页
动车组交路计划是高速铁路运输生产计划的核心问题之一。在研究编制动车组交路计划时充分考虑夜间停放、到发线运用条件等以确保计划的可实施性。以一级检修周期为时间跨度构建动车组运用接续网络,考虑夜间存放地点、车站到发线运用、... 动车组交路计划是高速铁路运输生产计划的核心问题之一。在研究编制动车组交路计划时充分考虑夜间停放、到发线运用条件等以确保计划的可实施性。以一级检修周期为时间跨度构建动车组运用接续网络,考虑夜间存放地点、车站到发线运用、检修里程和检修时间等约束,建立以动车组使用数量最小为目标的混合整数线性规划模型,开发两阶段分支定界算法进行求解。以某动车运用所担当的列车为案例,分析结果表明:在动车组夜间存放地点和到发线运用合理的情况下,构建的模型相比既有人工编制方法可以有效节省动车组使用数量,同时能编制动车组车站到发线运用方案及夜间存放方案,节约铁路部门运营成本,为相关人员编制动车组交路计划提供辅助参考。 展开更多
关键词 动车组 动车组交路计划 混合整数线性规划 到发线运用
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基于强化学习与遗传算法的机器人并行拆解序列规划方法
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作者 汪开普 马晓艺 +2 位作者 卢超 殷旅江 李新宇 《国防科技大学学报》 北大核心 2025年第2期24-34,共11页
在拆解序列规划问题中,为了提高拆解效率、降低拆解能耗,引入了机器人并行拆解模式,构建了机器人并行拆解序列规划模型,并设计了基于强化学习的遗传算法。为了验证模型的正确性,构造了混合整数线性规划模型。算法构造了基于目标导向的... 在拆解序列规划问题中,为了提高拆解效率、降低拆解能耗,引入了机器人并行拆解模式,构建了机器人并行拆解序列规划模型,并设计了基于强化学习的遗传算法。为了验证模型的正确性,构造了混合整数线性规划模型。算法构造了基于目标导向的编解码策略,以提高初始解的质量;采用Q学习来选择算法迭代过程中的最佳交叉策略和变异策略,以增强算法的自适应能力。在一个34项任务的发动机拆解案例中,通过与四种经典多目标算法对比,验证了所提算法的优越性;分析所得拆解方案,结果表明机器人并行拆解模式可以有效缩短完工时间,并降低拆解能耗。 展开更多
关键词 拆解序列规划 机器人并行拆解 混合整数线性规划模型 遗传算法 强化学习
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严重干扰下考虑空车调拨的动车组运用计划实时调整方法
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作者 钟庆伟 庾映雪 +3 位作者 田金玉 张永祥 闫旭 彭其渊 《铁道运输与经济》 北大核心 2025年第1期82-91,101,共11页
研究严重干扰场景下高速铁路网络动车组运用计划实时调整问题,根据调整后列车运行图,以偏离原动车组运用计划程度最小、取消车次数量最少、动车段(所)日常库存偏离最少及空车调拨次数最少为目标,在考虑车组改编及日常检修限制等安全约... 研究严重干扰场景下高速铁路网络动车组运用计划实时调整问题,根据调整后列车运行图,以偏离原动车组运用计划程度最小、取消车次数量最少、动车段(所)日常库存偏离最少及空车调拨次数最少为目标,在考虑车组改编及日常检修限制等安全约束条件下,基于车次接续建立两阶段整数线性规划模型。第一阶段模型旨在生成多种与原动车组运用计划方案相似的可行路径集合;第二阶段模型则保证具体执行各路径动车组的一致性,以及各备选动车组与其可能执行路径之间的检修可行性。最后以郑州局集团公司所辖部分高速铁路网络为例,对提出模型及算法的有效性进行验证,计算结果表明该方法能够快速实现多个场景问题的求解,为严重干扰下考虑空车调拨的动车组运用计划调整提供参考。 展开更多
关键词 高速铁路 动车组运用计划实时调整 整数线性规划模型 改编 空车调拨
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New Approach to Linear Stackelberg Problems with Multiple Leaders-followers
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作者 刘德峰 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期34-41,共8页
In this paper, we study linear static Stac kelberg problems with multiple leaders-followers in which each decision maker wi thin his group may or may not cooperate. An exact penalty function method is dev eloped. The ... In this paper, we study linear static Stac kelberg problems with multiple leaders-followers in which each decision maker wi thin his group may or may not cooperate. An exact penalty function method is dev eloped. The duality gaps of the followers’ problems are appended to the leaders’ objective function with a penalty. The structure leads to the decomposition of the composite problem into a series of linear programmings leading to an efficie nt algorithm. We prove that local optimality is reached for an exact penalty fun ction and illustrate the method with three examples. The model in this paper ext ends the stackelberg leader-follower model. 展开更多
关键词 Stackelberg game linear programming penalty function method
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