检索结果-南通市图书馆

Green resource allocation for mobile edge computing

在线全文

学校读者我要写书评

暂无评论

Digital Communications and Networks 2023年第5期9卷 1190-1199页

作者： Anqi Meng Guandong Wei Yao Zhao Xiaozheng Gao Zhanxin Yang State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China Engineering Center of Digital Audio and Video Communication University of ChinaBeijing100024China School of Information and Electronics Beijing Institute of TechnologyBeijing100081China

We investigate the green resource allocation to minimize the energy consumption of the users in mobile edge computing systems,where task offloading decisions,transmit power,and computation resource allocation are jointly *** considered energy consumption minimization problem is a non-convex mixed-integer nonlinear programming problem,which is challenging to ***,we develop a joint search and Successive Convex Approximation(SCA)scheme to optimize the non-integer variables and integer variables in the inner loop and outer loop,***,in the inner loop,we solve the optimization problem with fixed task offloading *** to the non-convex objective function and constraints,this optimization problem is still non-convex,and thus we employ the SCA method to obtain a solution satisfying the Karush-Kuhn-Tucker *** the outer loop,we optimize the offloading decisions through exhaustive ***,the computational complexity of the exhaustive search method is greatly *** reduce the complexity,a heuristic scheme is proposed to obtain a sub-optimal *** results demonstrate the effectiveness of the developed schemes.

关键词： Mobile edge computing Green communications mixed-integer programming Resource allocation

Aerial-ground collaborative routing with time constraints

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2023年第2期36卷 270-283页

作者： Jiahao XING Lichen SU Wenjing HONG Lu TONG Renli LYU Wenbo DU School of Electronics and Information Engineering Beihang UniversityBeijing 100091China School of Future Aerospace Technology/Shen Yuan Honors College Beihang UniversityBejing 100091China School of Automation Science and Electrical Engineering Beihang UniversityBejing 100091China Guangdong Provincial Key Laboratory of Brain-Inspired Intelligent Computation Shenzhen 518055China Department of Computer Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Research Institute of Frontier Science Beihang UniversityBeijing 100083China CAAC Key Laboratory of General Aviation Operation Civil Aviation Management Institute of ChinaBeijing 100102China

The advancement of autonomous technology makes electric-powered drones an excellent choice for flexible logistics services at the last mile delivery *** reach a balance between green transportation and competitive edge,the collaborative routing of drones in the air and trucks on the ground is increasingly invested in the next generation of delivery,where it is particularly reasonable to consider customer time windows and time-dependent travel times as two typical time-related factors in daily *** this paper,we propose the Vehicle Routing Problem with Drones under Time constraints(VRPD-T)and focus on the time constraints involved in realistic scenarios during the delivery.A mixed-integer linear programming model has been developed to minimize the total delivery completion ***,to overcome the limitations of standard solvers in handling large-scale complex issues,a space-time hybrid heuristic-based algorithm has been developed to effectively identify a high-quality *** numerical results produced from randomly generated instances demonstrate the effectiveness of the proposed algorithm.

关键词： Aerial-ground collaborative delivery mixed-integer programming Space-time hybrid heuristic algorithm Vehicle routing problem with drones Time-dependent travel times

An enlarged polygon method without binary variables for obstacle avoidance trajectory optimization

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2023年第8期36卷 284-297页

作者： Rouhe ZHANG Zihan XIE Changzhu WEI Naigang CUI School of Astronautics Harbin Institute of TechnologyHarbin 150090China

In this article,an Enlarged Polygon/Polyhedron(ELP)method without binary variables is proposed to represent the Convex Polygonal/Polyhedral Obstacle Avoidance(CPOA)constraints in trajectory ***,the equivalent condition of a point outside the convex set is given and proved ***,the ELP condition describing the CPOA constraints equivalently is given without introducing binary variables,and its geometric meaning is ***,the ELP method is used to transform the CPOA trajectory optimization problem into an optimal control problem without binary *** effectiveness and validity of ELP method are demonstrated through simulations with both simple linear dynamic model(unmanned aerial vehicle)and complex nonlinear dynamic model(hypersonic glide vehicle).Comparison indicates the computational time of ELP method is only 1%-20%of that of the traditional mixed-integer programming(MIP)method.

关键词： Enlarged polygon method Hypersonicglidevehicles mixed-integer programming No-fly zone Obstacle avoidance Trajectoryoptimization Unmanned aerial vehicles

Sequential dynamic resource allocation in multi-beam satellite systems:A learning-based optimization method

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2023年第6期36卷 288-301页

作者： Yixin HUANG Shufan WU Zhankui ZENG Zeyu KANG Zhongcheng MU Hai HUANG School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Academy of Spaceflight Technology Shanghai 200240China School of Astronautics Beihang UniversityBeijing 100191China

Multi-beam antenna and beam hopping technologies are an effective solution for scarce satellite frequency *** of the primary challenges accompanying with Multi-Beam Satellites(MBS)is an efficient Dynamic Resource Allocation(DRA)*** paper presents a learning-based Hybrid-Action Deep Q-Network(HADQN)algorithm to address the sequential decision-making optimization problem in *** using a parameterized hybrid action space,HADQN makes it possible to schedule the beam pattern and allocate transmitter power more *** pursue multiple long-term QoS requirements,HADQN adopts a multi-objective optimization method to decrease system transmission delay,loss ratio of data packets and power consumption load *** results demonstrate that the proposed HADQN algorithm is feasible and greatly reduces in-orbit energy consumption without compromising QoS performance.

关键词： Beam hopping Deep reinforcement learning Dynamic resource allocation mixed-integer programming Multi-beam satellite systems Multi-objective optimization

A comparative study of heuristic methods for cardinality constrained portfolio optimization

在线全文

学校读者我要写书评

暂无评论

高置信计算(英文) 2023年第1期3卷 23-30页

作者： Lei Fu Jun Li Shanwen Pu Bank of Jiangsu Nanjing 210001China School of Economics Fudan UniversityShanghai 200433China School of Information Management and Engineering Shanghai University of Finance and EconomicsShanghai 200433China

The cardinality constrained mean–variance(CCMV)portfolio selection model aims to identify a subset of the candidate assets such that the constructed portfolio has a guaranteed expected return and minimum *** formulating this model as the mixed-integer quadratic program(MIQP),the exact solution can be solved by a branch-and-bound ***,computational efficiency is the central issue in the time-sensitive portfolio investment due to its NP-hardness *** accelerate the solution speeds to CCMV portfolio optimization problems,we develop various heuristic methods based on techniques such as continuous relaxation,l1-norm approximation,integer optimization,and relaxation of semi-definite programming(SDP).We evaluate our heuristic methods by applying them to the US equity market *** experimental results show that our SDP-based method is effective in terms of the computation time and the approximation *** SDP-based method performs even better than a commercial MIQP solver when the computational time is *** addition,several investment companies in China have adopted our methods,gaining good *** paper sheds light on the computation optimization for financial investments.

关键词： Acceleration Mean-variance portfolio optimization Cardinality constraint mixed-integer programming

Mathematical Approach for Fleet Planning Under Complicated Circumstances

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Shanghai Jiaotong university(Science) 2014年第2期19卷 241-250页

作者：杨秋平张皞桑惠云谢新连 China Waterborne Transport Research Institute Transportation Management College Dalian Maritime University

In order to facilitate the scientific management of large-sized shipping companies, fleet planning under complicated circumstances has been studied. Based on multiple influencing factors such as the techno-economic status of ships, the investment capacity of company, the possible purchase of new ships, the buying/selling of second-hand vessels and the chartering/renting of ships, a mixed-integer programming model for fleet planning has been established. A large-sized shipping company is utilized to make an empirical study, and Benders decomposition algorithm is employed to test the applicability of the proposed model. The result shows that the model is capable for multi-route, multi-ship and large-scaled fleet planning and thus helpful to support the decision making of large-sized shipping companies.

关键词： fleet planning mixed-integer programming Benders decomposition algorithm

Robust energy-efficient train speed profile optimization in a scenario-based position-time-speed network

在线全文

学校读者我要写书评

暂无评论

Frontiers of Engineering Management 2021年第4期8卷 595-614页

作者： Yu CHENG Jiateng YIN Lixing YANG State Key Laboratory of Rail Traffic Control&Safety Beijing Jiaotong UniversityBeijing 100044China E-mail:jiatyin@***

Train speed profile optimization is an efficient approach to reducing energy consumption in urban rail transit *** from most existing studies that assume deterministic parameters as model inputs,this paper proposes a robust energy-efficient train speed profile optimization approach by considering the uncertainty of train modeling ***,we first construct a scenario-based position-time-speed(PTS)network by considering resistance parameters as discrete scenariobased random ***,a percentile reliability model is proposed to generate a robust train speed profile,by which the scenario-based energy consumption is less than the model objective value at a confidence *** solve the model efficiently,we present several algorithms to eliminate the infeasible nodes and arcs in the PTS network and propose a model reformulation strategy to transform the original model into an equivalent linear programming ***,on the basis of our field test data collected in Beijing metro Yizhuang line,a series of experiments are conducted to verify the effectiveness of the model and analyze the influences of parameter uncertainties on the generated train speed profile.

关键词： robust train speed profile percentile reliability model scenario-based position-time-speed network mixed-integer programming

LDSE Algorithm for Constrained Multi-Objective Optimization with mixed Variables

在线全文

学校读者我要写书评

暂无评论

LDSE Algorithm for Constrained Multi-Objective Optimization ...

The 4th Across-strait Workshop on Shock Wave/Vortex Interaction

作者： Changtong Luo~*,Shao-Liang Zhang~+ Department of Computational Science and Engineering Nagoya University, Nagoya 464-8603,Japan

A bi-level tournament selection method for handling multi-objectives and constraints is provided for low dimensional simplex evolution(LDSE).The idea is general and can apply to other evo utionary algorithms.

关键词： multi-objective optimization evolutionary algorithm genetic algorithm constraints handling mixed-integer programming

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

一种集成电路全局布局混合整数规划模型