检索结果-内蒙古大学图书馆

Path Planning Optimization Based Interference Awareness for Mobile Robots in mmWave Multi Cell Networks

IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2024年第9期73卷 13639-13650页

作者： Ren, Yijing Friderikos, Vasilis Kings Coll London Dept Engn London WC2R 2LS England

The emerging beyond fifth-generation (B5G) and envisioned sixth-generation (6G) wireless networks are considered as key enablers in supporting a diversified set of applications for industrial mobile robots (MRs). The scenario under investigation in this paper relates to mobile robots that autonomously roam on an industrial floor and perform a variety of tasks at different locations, whilst utilizing high directivity beamformers in millimeter wave (mmWave) small cells. In such scenarios, the potential close proximity of mobile robots connected to different base stations may cause excessive levels of interference having as a net result a decrease in the overall achievable data rate in the network. To resolve this issue, a novel MR optimal path planning scheme via a mixed integer programming formulation is proposed where robots' trajectory is considered jointly with the interference level at different beam sectors. To combat the curse of dimensionality, a geographical division clustering based MR path planning heuristic scheme is proposed to enable scalability and real-time decision making. The proposed heuristic aims to find a low interference path for each mobile robot whilst achieving a near-optimal performance. A wide set of numerical investigations reveal that the proposed optimal and heuristic path planning schemes for the mmWave connected mobile robots can improve the overall achievable throughput by up to 93% compared to an interference oblivious scheme without penalizing the total travel time.

关键词： Interference Robots Millimeter wave communication Optimization Mobile robots Service robots Trajectory Beamforming beyond 5G industry 4.0 mixed integer linear programming mobile robots path planning

来源：评论

学校读者我要写书评

暂无评论

A multi-road quasi network flow model for the vertical alignment optimization of a road network

引用

ENGINEERING OPTIMIZATION 2024年第7期56卷 1140-1163页

作者： Ayman, Khandoker Md Hare, Warren Lucet, Yves Univ British Columbia Dept Comp Sci Okanagan Campus Kelowna BC Canada Univ British Columbia Dept Math Okanagan Campus Kelowna BC Canada

Minimizing earthwork costs is crucial in the optimization of vertical alignment. In this article, the previous quasi network flow model for the vertical alignment optimization of a single road is extended to a multi-road network. A 'one-at-a-time' method is first examined to solve the optimization problem and it is noted that this method is effectively what is currently used in practice. Two academic test problems are used to demonstrate that this method is not optimal. This leads to the development of three novel methods to solve the optimization problem: no-flow, with-flow and divide-and-conquer. It is noted that the with-flow method guarantees global optimality. All methods are compared on two real-world case studies. On small road networks, the with-flow method decreases costs by 7.4%, and achieves a 20 times speedup over the one-at-a-time method. On long road networks, the divide-and-conquer method is faster than all other methods without any notable cost difference. However, the divide-and-conquer method is an heuristic and cannot guarantee that it returns a global minimum.

关键词： Road network optimization vertical alignment mixed integer linear programming quasi network

来源：评论

学校读者我要写书评

暂无评论

Long-term maintenance optimization for integrated mining operations

引用

OPTIMIZATION AND ENGINEERING 2024年第4期25卷 1817-1848页

作者： Yang, Yingying Loxton, Ryan Rohl, Andrew L. Bui, Hoa T. Curtin Univ ARC Training Ctr Transforming Maintenance Data Sc Perth WA Australia

Maintenance activities are inevitable and costly in integrated mining operations. Conducting maintenance may require the whole system, or sub-units of the system, to be shut down temporarily. These maintenance activities not only disrupt the unit being shut down, but they also have consequences for inventory levels and product flow downstream. In this paper, we consider an interconnected mining system in which there are complicated maintenance relationships and stock accumulation at intermediate nodes. We propose a time-indexed mixed-integer linear programming formulation to optimize the long-term integrated maintenance plan and maximize the total throughput. We also devise an algorithm, which combines Benders decomposition and Lagrangian relaxation, to accelerate the computational speed. To validate our mathematical model, we perform simulations for a real-world case study in the iron ore industry. The results show that our method can yield better solutions than CPLEX optimization solver alone in faster time.

关键词： Long-term maintenance planning Optimization mixed integer linear programming Integrated network Mining industry

来源：评论

学校读者我要写书评

暂无评论

minChemBio: Expanding Chemical Synthesis with Chemo-Enzymatic Pathways Using Minimal Transitions

引用

ACS SYNTHETIC BIOLOGY 2025年第3期14卷 756-770页

作者： Anand, Mohit Upadhyay, Vikas Maranas, Costas D. Penn State Univ State Coll PA 16802 USA

Chemo-enzymatic pathway design aims to combine the strengths of enzymatic with chemical synthesis to traverse biomolecular design space more efficiently. While chemical reactions often struggle with regioselectivity and stereoselectivity, enzymatic conversions often encounter limitations of low enzyme activity or availability. Optimally integrating both approaches provides an opportunity to identify efficient pathways beyond the capabilities of either modality. Recently, studies have shown the advantage of leveraging enzymatic steps into industrial-scale chemical processes, such as for the blood sugar regulator Sitagliptin (Merck) and the HIV protease inhibitor Darunavir (Prozomix). Designing optimal chemo-enzymatic pathways is a complex task. It requires navigating a high-dimensional search space of potential reactions that combine individual chemical and biochemical steps while at the same time minimizing transitions between chemical catalysis and bioreactions. Here, we introduce an algorithmic approach, minChemBio, that relies on solving a mixed-integer linear programming (MILP) problem by optimally searching through known chemical and enzymatic steps extracted from the United States Patent Office (USPTO) and MetaNetX databases, respectively. minChemBio allows for the minimization of transitions between chemical and biological reactions in the pathway, thus reducing the need for costly separation and purification steps required. minChemBio was benchmarked on three case studies involving the synthesis of 2-5-furandicarboxylic acid, terephthalate, and 3-hydroxybutyrate. Identified designs included both established literature pathways as well as unexplored ones which were compared against pathways identified by existing retrosynthetic tools. minChemBio fills a current gap in the space of pathway retrosynthesis tools by controlling and minimizing the transitions between chemical catalysis and biocatalytic steps. It is accessible to users through open-source code (htt

关键词： Computational Synthesis Planning Chemo-enzymatic Pathways Minimal Transitions mixed integer linear programming

来源：评论

学校读者我要写书评

暂无评论

Rate Adaptation Technique for Media Streaming Over QUIC With Limited Backhaul

引用

IEEE ACCESS 2024年 12卷 139028-139041页

作者： Dwijaksara, Made Harta Hilman, Muhammad Hafizhuddin Lee, Chankyun Lee, Wonhyuk Univ Indonesia Fac Comp Sci Comp Syst Lab CSL Kota Depok 16425 West Java Indonesia Korea Inst Sci & Technol Informat Quantum Network Res Ctr Daejeon 34141 South Korea

The rapid proliferation of mobile devices has caused a significant surge in Internet traffic, mainly due to video streaming services, which account for up to 65% of the total volume. As a primary contributor to Internet traffic, video streaming services must use bandwidth efficiently to avoid overwhelming networks with unnecessary traffic. It is not trivial for media streaming services to utilize bandwidth efficiently while achieving scalability and interactivity. Media over QUIC (MoQ) is a promising new standard for realizing both scalable and interactive streaming services. However, due to its infancy, the selection of a proper bit rate for each video segment to be transmitted (also known as rate adaptation) in MoQ has yet to be explored. Inappropriate video bit rate selection can lead to a deterioration of the user's quality of experience (QoE) and inefficient bandwidth utilization. Furthermore, the rate adaptation problem becomes more complex due to the limitation of backhaul bandwidth. The rate adaptation technique should consider the client parameters (i.e., client bandwidth) and backhaul bandwidth usage known only to the server (server parameters). This paper proposes the rate adaptation technique designed for MoQ that considers both the client and server parameters. We have implemented the proposed scheme and evaluated its performance under realistic scenarios. Our experimental results reveal that the proposed technique has a 70% lower packet delay rate and a 10% higher bandwidth utilization compared to the IFA-based, RENO-based, and DASH-Google. These results demonstrate the novelty and the benefits of the proposed scheme.

关键词： Streaming media Bandwidth Servers Bit rate Backhaul networks Real-time systems Quality of experience mixed integer linear programming Bit rate adaptation media streaming QUIC dynamic adaptive streaming over HTTP (DASH) limited backhaul mixed integer linear programming (MILP)

来源：评论

学校读者我要写书评

暂无评论

Cost-based assembly line balancing and worker-cobot assignment problem under ergonomic constraints

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GA...

引用

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY 2024年第1期39卷 461-472页

作者： Bekdemir, Perihan Tasan, Seren Ozmehmet Eskisehir Tech Univ Fac Engn Dept Ind Engn TR-26555 Eskisehir Turkiye Dokuz Eylul Univ Fac Engn Dept Ind Engn TR-35390 Izmir Turkiye

For many years, the assembly line balancing problem (ALBP) has been discussed with different solution approaches in the literature. Recently, the use of collaborative robots (cobots) that can work at the same or different stations with the workers on the assembly line has become very popular. The problem of calculating the break times with the energy expenditure of the workers above a certain level has also been evaluated from the perspective of ergonomics. In this study, the cost-based assembly line balancing and worker-cobot assignment problem (ALBWCAP) under ergonomic constraints is discussed and a mixed integer linear programming model (MILP) is proposed to solve the problem. To evaluate the effectiveness of the cobots in assembly lines, a total of four different scenarios;i.e. cost-based assembly line only with the manual workforce, the cost-based ALBWCAP where the ergonomics perspective is ignored, cost-based ALBWCAP where the ergonomics perspective is ignored with different parameters in objective function, and the cost -based ALBWCAP where the ergonomics perspective is addressed-change in energy expenditures were considered and their results were compared. and their results were compared.

关键词： Cobot ergonomic issues mixed integer linear programming linearization cost-based

来源：评论

学校读者我要写书评

暂无评论

Dynamic flow control model and algorithm for metro network under FIFO condition

引用

TRANSPORTATION RESEARCH PART B-METHODOLOGICAL 2024年 190卷

作者： Zhang, Ping Wu, Jianjun Wang, Kai Qu, Yunchao Long, Jiancheng Beijing Jiaotong Univ Sch Syst Sci Beijing 100044 Peoples R China Dalian Univ Technol Sch Econ & Management Dalian 116024 Peoples R China Tsinghua Univ Sch Vehicle & Mobil Beijing 100084 Peoples R China Hefei Univ Technol Sch Automot & Transportat Engn Hefei 230009 Peoples R China

Implementing passenger flow control strategies is an effective approach to reducing commuter travel delays and ensuring crowd safety in a congested metro network. Due to the intricacy of the interweaving of passenger flows between various lines and stations, the development of a scientific passenger flow control strategy is challenging in the networked mode of operation. The first-in-first-out (FIFO) rule can ensure service fairness and optimal operation by accurate modeling passenger queuing dynamics, but it is rarely considered in existing studies. Inspired by the traditional dynamic traffic assignment models, we propose a novel passenger flow control model with the FIFO rule to find a more reasonable control strategy for a metro network. Unlike road traffic systems, the FIFO rule is formulated as a set of linear constraints to explicitly capture the passenger queuing properties at origin stations. The passenger flow control problem with the FIFO rule is then modeled as a mixed integer linear programming model, which can significantly reduce the model complexity. To reach a high-quality solution, we propose an efficient rolling horizon decomposition approach. In the algorithm, the planning horizon is rolled forward from the current time, and the effects of subsequent periods are considered at each iteration. Besides, a dynamic procedure for loading passengers is developed to evaluate the bounds between the proposed approach and other flow control strategies. The proposed model and algorithm are then applied to solve the problems in test and real metro networks. The numerical results demonstrate the validity of the model's properties and the algorithm's performance.

关键词： Metro network oversaturation Passenger flow control mixed integer linear programming Decomposition heuristic

来源：评论

学校读者我要写书评

暂无评论

Integrated maintenance and production scheduling for unrelated parallel machines with setup times

引用

FLEXIBLE SERVICES AND MANUFACTURING JOURNAL 2024年第3期36卷 1046-1079页

作者： Geurtsen, Michael Adan, Jelle Akcay, Alp Eindhoven Univ Technol Sch Ind Engn De Zaale NL-5600 MB Eindhoven Netherlands Nexperia Jonkerbosplein 52 NL-6534 AB Nijmegen Netherlands

This paper considers jointly scheduling the production and resource-constrained maintenance activities in a manufacturing setting with unrelated parallel machines. In particular, a single maintenance activity needs to be scheduled on each machine in one of its available time windows, and the maintenance activities require a scarce resource, thereby limiting the number of maintenance activities that can be scheduled simultaneously on different machines. In addition, machine- and sequence-dependent setup times, machine eligibility constraints and job-specific release and due dates are considered. A mixed-integer linear program is formulated with objectives including the makespan and, motivated from practice, a weighted sum of total production completion times at machines and total job tardiness. Additionally, a hybrid genetic algorithm with a novel solution representation is proposed for solving industry-scale large instances. A case study is performed with real-world data from a semiconductor manufacturer, where production and maintenance are scheduled separately. The benefit of simultaneously scheduling production and maintenance is investigated. Tests with real-world data show that the proposed model results in schedules that substantially improve the current factory practice.

关键词： Production scheduling Parallel machines Integrated planning Setup times mixed integer linear programming Hybrid genetic algorithm

来源：评论

学校读者我要写书评

暂无评论

Multi-Period Power System Risk Minimization Under Wildfire Disruptions

引用

IEEE TRANSACTIONS ON POWER SYSTEMS 2024年第5期39卷 6305-6318页

作者： Yang, Hanbin Rhodes, Noah Yang, Haoxiang Roald, Line Ntaimo, Lewis Chinese Univ Hong Kong Shenzhen Sch Data Sci Shenzhen 518172 Peoples R China Univ Wisconsin Madison Elect & Comp Engn Madison WI 53706 USA Texas A&M Univ Ind & Syst Engn College Stn TX 77843 USA

Natural wildfire becomes increasingly frequent as climate change evolves, posing a growing threat to power systems, while grid failures simultaneously fuel the most destructive wildfires. Preemptive de-energization of grid equipment is effective in mitigating grid-induced wildfires but may cause significant power outages during natural wildfires. This paper proposes a novel two-stage stochastic program for planning preemptive de-energization and solves it via an enhanced Lagrangian cut decomposition algorithm. We model wildfire events as stochastic disruptions with random magnitude and timing. The stochastic program maximizes the electricity delivered while proactively de-energizing components over multiple time periods to reduce wildfire risks. We use a cellular automaton process to sample grid failure and wildfire scenarios driven by realistic risk and environmental factors. We test our method on an augmented version of the RTS-GLMC test case in Southern California and compare it with four benchmark cases, including deterministic, wait-and-see, and robust optimization formulations as well as a comparison with prior wildfire risk optimization. Our method reduces wildfire damage costs and load-shedding losses, and our nominal plan is robust against uncertainty perturbation.

关键词： Wildfires Climate change Lagrangian functions mixed integer linear programming Risk management Stochastic processes Power system reliability Decomposition algorithm de-energization Lagrangian cut optimal power flow stochastic mixed-integer programming wildfire risk

来源：评论

学校读者我要写书评

暂无评论

Use statistical analysis to approximate integrated order batching problem

引用

INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH 2024年第12期62卷 4349-4371页

作者： Xue, Sen Gao, Chuanhou Zhejiang Univ Sch Math Sci Hangzhou Peoples R China

This paper highlights the tight relationship between the picking and packing processes in warehouse management and the need to consider them as an integrated problem. The study describes and models this integrated problem as a mixed-integer programming model, to optimise overall labour costs by determining the assignment of the subsets of orders, i.e. batches, for picking and packing. To address the issue of model complexity, the paper presents a statistical-based framework for generating approximate models and selecting the optimal one through examination. Based on the examination results, a pair-swapping heuristic is additionally proposed to be combined as a hybrid algorithm. Numerical experiments based on a real-world case demonstrate the effectiveness of the framework-proposed and selected hybrid algorithm by comparison with other framework-proposed approximate models, a solver, and existing heuristics. Our findings indicate that the combined usage of integrated picking and packing processes planning and the hybrid algorithm proposed and selected within the statistical-based framework can effectively reduce the cost of warehouse management.

关键词： Logistics warehouse order batching mixed integer linear programming Monte Carlo method statistical methods

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：