检索结果-内蒙古大学图书馆

15th RIVF International Conference on Computing and Communication Technologies (RIVF)

作者： Chi-Hieu Nguyen Khanh-Van Nguyen Hanoi Univ Sci & Technol Hanoi Vietnam

ISBN: (纸本)9781665404358

In this paper, we study the problem of gathering data from large-scale wireless sensor networks using multiple unmanned air vehicles (UAVs) to gather data at designated rendezvouses, where the goal is to maximize the network lifetime. Previous proposals often consider a practical approach where the problem of determining a data gathering scheme is decomposed into 2 sub-problems: i) partitioning the networks into clusters for determining the rendezvouses as these obtained cluster heads;and ii) determining the paths for a set of a given number of UAVs to come gathering data at these rendezvouses which have been harvesting data within each local clusters, respectively. We try to deal with this as a whole optimization problem, expecting a significant increase in computation complexity which would bring new challenge in creating practical solutions for large-scale WSNs. We introduce two alternatives mixed-integer linear programming (MILP) formulations and we show that our best model could solve the problem instances optimally with up to 50 sensor nodes in less than 30 minutes. Next, we propose a heuristic idea to reduce the number of variables in implementing the 3-index model to effectively handle larger-scale networks with size in hundreds. The experiment results show that our heuristic approach significantly prolongs the network lifetime compared to existing most efficient proposals.

关键词： Wireless sensor networks Costs Computational modeling Autonomous aerial vehicles Communications technology mixed integer linear programming Proposals

来源：评论

学校读者我要写书评

暂无评论

Towards the Identification of Maximal Coherent Cut-Sets Within Power Grids 11

Towards the Identification of Maximal Coherent Cut-Sets With...

引用

11th IEEE-PES Innovative Smart Grid Technologies Europe (IEEE-PES ISGT Europe)

作者： Beiranvand, Arash Cuffe, Paul Univ Coll Dublin Sch Elect & Elect Engn Dublin Ireland

ISBN: (纸本)9781665448758

This paper formulates and then adapts a mixed integer linear programming (MILP) model for partitioning a graph into a desirable number of internally connected subgraphs to identify the maximal coherent cut-set for a power grid. For a particular operational snapshot of the grid, a coherent cut-set refers to a set of lines within the grid with the same flow directionality whose removals splits the grid into exactly two internally connected sub-grids. Such cut-sets are of interest as they can represent operational vulnerabilities. This paper suggests a novel methodology that directly detects the maximal coherent cut-sets for power grids. Two important applications are considered for the suggested methodology: i) a novel (N - kappa) analysis, ii) identifying the worst coherent cut-set that each line is involved in. Moreover, a novel Sankey diagram-based visualisation technique is introduced to portray the grids and the detected cut-sets, improving the situational awareness in the control room.

关键词： Visualization Adaptation models Europe Smart grids mixed integer linear programming

来源：评论

学校读者我要写书评

暂无评论

Efficient Mandatory Lane Changing of Connected and Autonomous Vehicles 94

Efficient Mandatory Lane Changing of Connected and Autonomou...

引用

94th IEEE Vehicular Technology Conference (VTC-Fall)

作者： Lin, Shang-Chien Kung, Chia-Chu Lin, Lee Lin, Chung-Wei Jiang, Iris Hui-Ru Natl Taiwan Univ Taipei Taiwan

ISBN: (纸本)9781665413688

In a mandatory lane-changing scenario, vehicles need to move to their target lanes before the end of a road segment. Mandatory lane changing usually happens near a highway ramp, and it is one major source of traffic congestion and delay. The advance of connected and autonomous vehicles supports to solve the problem in a centralized and precise way. We formulate a mandatory lane-changing problem and propose a mixed-integer linear programming (MILP) approach to find an optimal solution. We then propose an MILP-based incremental-window algorithm to solve the problem efficiently. Experimental results show that the MILP-based incremental-window algorithm can take much less computation time and achieve almost the same solution quality, compared with the original MILP approach. The advantage of efficiency yet sufficient effectiveness matches the need of high-level control (decision of passing order) well.

关键词： Vehicular and wireless technologies Connected vehicles Roads Conferences mixed integer linear programming Delays Autonomous vehicles

来源：评论

学校读者我要写书评

暂无评论

Sparsification for Fast Optimal Multi-Robot Path Planning in Lazy Compilation Schemes

Sparsification for Fast Optimal Multi-Robot Path Planning in...

引用

IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)

作者： Surynek, Pavel Czech Tech Univ Fac Informat Technol Thakurova 9 Prague 16000 6 Czech Republic

ISBN: (纸本)9781665417143

Path planning for multiple robots (MRPP) represents a task of finding non-colliding paths for robots via which they can navigate from their initial positions to specified goal positions. The problem is often modeled using undirected graphs where robots move between vertices across edges while no two robots can simultaneously occupy the same vertex nor can traverse an edge in opposite directions. Contemporary optimal solving algorithms include dedicated search-based methods, that solve the problem directly, and compilation-based algorithms that reduce MRPP to a different formalism for which an efficient solver exists, such as constraint programming (CP), mixed integer linear programming (MILP), or Boolean satisfiability (SAT). In this paper, we enhance existing SAT-based algorithm for MRPP via sparsification of the set of candidate paths for each robot from which the target Boolean encoding is derived. Suggested sparsification of the set of paths led to a smaller target Boolean formulae that can be constructed and solved faster while optimality guarantees of the approach have been kept.

关键词： Constraint handling Navigation Heuristic algorithms Search problems Path planning Encoding mixed integer linear programming

来源：评论

学校读者我要写书评

暂无评论

A mathematical modeling for simultaneous routing and scheduling of logging trucks in the forest supply chain

引用

FOREST POLICY AND ECONOMICS 2022年第0期136卷 102693-102693页

作者： Melchiori, Luciana Nasini, Graciela Montagna, Jorge M. Corsano, Gabriela CONICET UTN Inst Desarrollo & Diseno INGAR S3002GJC RA-3657 Avellaneda Santa Fe Argentina Univ Nacl Litoral Fac Ingn Quim RA-2829 Santiago Del Estero Santa Fe Argentina Univ Nacl Rosario Fac Ciencias Exactas Ingn & Agrimensura Rosario Argentina

Transportation cost in the forest industry highly impacts on the overall costs of the supply chain, and therefore it must be optimized for improving profitability. Considering the problem characteristics, the decisions related to the transport problem, such as allocation, routing, and scheduling, are usually decoupled, resorting to different decomposition strategies. As a result, suboptimal and underperforming solutions are obtained. In this article, decisions about raw material allocation, routing and scheduling are simultaneously solved through a mixed integer linear programming model. The proposed model involves an arc-based formulation for routing and a time grid discretization, including the definition of loading and unloading shifts for scheduling. This leads to detailed transportation planning for a homogeneous logging truck fleet that must fulfill the demand of varied raw material at minimum cost. Examples and performance tests are provided to assess the capabilities of the proposed exact approach.

关键词： Routing Scheduling mixed integer linear programming Forest industry Optimization

来源：评论

学校读者我要写书评

暂无评论

Energy-efficient automatic train operation for high-speed railways: Considering discrete notches and neutral sections

引用

TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES 2022年 145卷

作者： Wei, Guodong Zhu, Songwei Wang, Yihui Chen, Wenjie Lu, Shaofeng Sha, Shuo Li, Le Beijing Jiaotong Univ Natl Engn Res Ctr Rail Transportat Operat & Contro Beijing Peoples R China Beijing Jiaotong Univ State Key Lab Rail Traff Control & Safety Beijing Peoples R China TaiYuan Iron & Steel Grp CO LTD Taiyuan Peoples R China South China Univ Technol Shien Ming Wu Sch Intelligent Engn Guangzhou Peoples R China Qingdao Hisense Microun Signal Co LTD Beijing Peoples R China

The energy-efficient driving of automatic train operation (ATO) system in high-speed railway systems has attracted more and more attention. Different from the energy-efficient automatic train control problem for metro trains, the traction/braking forces given by high-speed ATO systems are currently not continuous but discrete values corresponding to traction/braking notches due to the limited communication interface between ATO systems and rolling stocks. In addition, since high-speed trains are powered by single-phase alternating current, there is no power supply for train traction in neutral sections, which is introduced to separate two catenaries powered by currents with different phases. In this paper, we propose a discrete-space based mathematical formulation for the energy-efficient automatic train control problem for high-speed trains, where binary variables are introduced to indicate the traction/braking notch selections and to indicate whether a discrete space interval is a neutral section or not. The mathematical formulation is then transformed into a mixed integer linear programming (MILP) model, which can be solved by existing solvers. However, due to the discretization of the space the discrete traction/braking notches, the resulting MILP problem could be infeasible and the optimal driving strategy cannot be obtained. Hence, we present a novel relaxation method, i.e., the final braking notch relaxation method, to relax a few constraints in the final braking phase and to generate a feasible speed profile. Comprehensive experiments are investigated based on Beijing-Harbin high-speed railway line, where the energy consumption of the speed profiles with discrete (i.e., notch-based) traction/braking forces is slightly higher than that with continuous traction/braking forces. Moreover, the impacts of the neutral section locations and the effects of different numbers of traction/braking notches are deeply analyzed.

关键词： Automatic train operation Trajectory optimization Multiple notches High-speed railway mixed integer linear programming

来源：评论

学校读者我要写书评

暂无评论

Two-level Weight Optimization of Composite Laminates using integer programming

Two-level Weight Optimization of Composite Laminates using I...

引用

AIAA Science and Technology Forum and Exposition (AIAA SciTech Forum)

作者： Borwankar, Pranav Zhao, Wei Kapania, Rakesh K. Bansal, Manish Virginia Polytech Inst & State Univ Kevin T Crofton Dept Aerosp & Ocean Engn Blacksburg VA 24060 USA Virginia Polytech Inst & State Univ Dept Ind & Syst Engn Blacksburg VA 24060 USA

ISBN: (数字)9781624106095

ISBN: (纸本)9781624106095

Composite laminate optimization requires the satisfaction of various constraints wherein the various design parameters such as the ply thicknesses and orientations can only take discrete values prescribed by the manufacturer. Different heuristics, such as particle swarm or genetic algorithms, are inefficient in such cases primarily because they provide sub-optimal solutions and are computationally expensive. In contrast, with the help of binary decision variables, mixed integer programming (MIP) can be adapted to efficiently optimize such laminates. Using a commercially available MIP solver Gurobi [1], this paper presents an approach using integer programming that can be used in the optimization of composite laminates subjected to failure constraints that are non-linear in terms of design variables. Initially, buckling load maximization for a simply-supported laminated plate is demonstrated using integer linear programming. The formulation is then modified to minimize the laminate weight for a given external bi-axial compressive load and subjected to buckling and material failure constraints. The modified problem is optimized with a nested bi-level approach using a combination of integer programming and a gradient-based optimizer (GBO). Finally, a two-level, sequential method is demonstrated which can be used for GBO-MIP or MIP-MIP combinations to optimize laminates subjected to constraints of polynomial order higher than two.

关键词： Composite Laminates Optimization Algorithm Genetic Algorithm Finite Element Modeling Evolutionary Algorithm mixed integer linear programming Aspect Ratio Annealing Techniques Composite Structures Transverse Shear

来源：评论

学校读者我要写书评

暂无评论

Urban Distribution Network Planning Considering Block Loads 3

Urban Distribution Network Planning Considering Block Loads

引用

3rd Asia Energy and Electrical Engineering Symposium (AEEES)

作者： Fang, Zhen Wang, Mingqiang Li, Jianying Wang, Zhixin Shandong Univ Key Lab Power Syst Intelligent Dispatch & Control Minist Educ Jinan Peoples R China

ISBN: (纸本)9781665425513

Urban distribution network planning is an important distribution network planning problem which needs to consider the street layout and block loads. Traditionally, the load within a block area is taken as a single load point. In this paper, a new urban distribution network planning model is proposed. The location and sizing of substations, and the routing and capacity of distribution power lines are simultaneously optimized. The load in a block is distributed to the surrounding segments, and then distributed to the adjacent junctions of the segments. The model belongs to a mixed integer linear programming problem and it can be solved by state-of-art commercial solver. The validity and effectiveness of the proposed model are illustrated by case studies.

关键词： block loads distribution network planning mixed integer linear programming street layout

来源：评论

学校读者我要写书评

暂无评论

Decision Guidance Framework for a Hybrid Renewable Energy System Investment Model 10th

Decision Guidance Framework for a Hybrid Renewable Energy Sy...

引用

10th International Conference on Operations Research and Enterprise Systems (ICORES)

作者： Levy, Roberto Brodsky, Alexander George Mason Univ Comp Sci Dept Fairfax VA 22030 USA

ISBN: (纸本)9789897584855

This paper focuses on making optimal investment and operational recommendations for a Hybrid Renewable Energy System (HRES). For this purpose we develop a modular composite analytic performance model for HRES investment, which is based on an extensible library of atomic component models, including renewable sources such as solar and wind, power storage, power contracts, and programmable customer loads' switches. The performance model formally expresses feasibility constraints and key performance indicators, including total tost of ownership, environment impact, and infrastructure resilience, as a function of investment and operational decision variables. Based on the performance model, we design and develop a decision guidance system to enable actionable investment recommendations that optimize key performance indicators subject to the operational constraints associated with the network. Finally, we demonstrate the model in a case study based on a real world example for a municipal electric utility.

关键词： Hybrid Renewable Energy System mixed integer linear programming Optimization Power Networks Investment Decision Guidance

来源：评论

学校读者我要写书评

暂无评论

Heterogeneous Fixed-wing Aerial Vehicles for Resilient Coverage of an Area

Heterogeneous Fixed-wing Aerial Vehicles for Resilient Cover...

引用

AIAA Science and Technology Forum and Exposition (AIAA SciTech Forum)

作者： Shriwastav, Sachin Song, Zhuoyuan Univ Hawaii Manoa Mech Engn Honolulu HI 96822 USA

ISBN: (数字)9781624106095

ISBN: (纸本)9781624106095

This paper presents a distributed approach to provide persistent coverage of an arbitrarily shaped area using heterogeneous coverage of fixed-wing unmanned aerial vehicles (UAVs), and to recover from simultaneous failures of multiple UAVs. The proposed approach discusses level-homogeneous deployment and maintenance of a homogeneous fleet of fixed-wing UAVs given the boundary information and the minimum loitering radius. The UAVs are deployed at different altitude levels to provide heterogeneous coverage and sensing. We use an efficient square packing method to deploy the UAVs, given the minimum loiter radius and the area boundary. The UAVs loiter over the circles inscribed over these packing squares in a synchronized motion to fulfill the full coverage objective. An top-down hierarchy of the square packing, where each outer square (super-square) is partitioned into four equal-sized inner squares (sub-square), is exploited to introduce resilience in the deployed UAV-network. For a failed sub-square UAV, a replacement neighbor is chosen considering the effective coverage and deployed to the corresponding super-square at a higher altitude to recover full coverage, trading-off with the quality of coverage of the sub-area. This is a distributed approach as all the decision making is done within close range of the loss region, and it can be scaled and adapted to various large scale area and UAV configurations. Simulation results have been presented to illustrate and verify the applicability of the approach.

关键词： Unmanned Aerial Vehicle Damage Assessment Path Planning mixed integer linear programming Aircraft Dynamics Isotropic Antenna Rotor Systems Flight Level Flight Planning Sweep Angle

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：