检索结果-内蒙古大学图书馆

Peer-to-peer energy exchange, autonomy goals, and financial rewards in Saudi Arabia households

AIN SHAMS ENGINEERING JOURNAL 2023年第12期14卷

作者： Lami, Badr Alferidi, Ahmad Alsolami, Mohammed Ben Slama, Sami Taibah Univ Coll Engn Dept Elect Engn POB 344 Al Madina 41411 Almonawara Saudi Arabia Taibah Univ Coll Engn Elect Engn Dept Al Madinah Saudi Arabia King Abdelaziz Univ Appl Coll Jeddah 22254 Saudi Arabia Fac Sci Tunis El Manar Anal & Proc Elect & Energy Syst Unit Tunis 2092 Tunisia

Peer-to-Peer energy trading is becoming increasingly essential and attracting a significant centralized transient energy trading market, an optimization model interest from companies and academics. As a result, new methods of creation and implementation have been developed. The deployment of the con-sumer concept, which combines residential needs with photovoltaic and battery storage systems, has been proposed as a viable approach to promote the integration of renewable energies with neighboring energy consumers' distribution networks. Therefore, this paper presents an innovative group of grid -connected residential consumers and communities that uses an appropriate MILP method to share, orga-nize and schedule surplus energy generated from distributed energy resources (DER) with neighboring energy consumers/deficit. The energy community investigated in this study consists of four consumers (a residential load and two consumers, a solar PV system and a battery storage system), an energy com-munity manager, and an energy seller, all connected to a distribution network. The proposed market model aims to investigate the economic benefits of renewable energy sources participating in centralized transit energy trading. A centralized strategy is used in transit energy trading between 10 proactive con-sumers and the energy network, with the energy community manager overseeing trading operations in the energy community. In the centralized transient energy trading market, an optimization model is pro-posed to increase the financial benefits of rooftop solar PV/ESS systems.(c) 2023 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Ain Shams *** is an open access article under the CC BY-NC-ND license (http://***/licenses/ by-nc-nd/4.0/).

关键词： Prosumer Peer -to -peer energy exchange mixed integer linear programming Home Energy Management System

来源：评论

学校读者我要写书评

暂无评论

One-shot models for local core network placement and traffic optimization in self deployable networks

引用

JOURNAL OF NETWORK AND COMPUTER APPLICATIONS 2023年第1期219卷

作者： Bechkit, Asma Melit, Ali Univ Jijel Fac Exact Sci & Comp Sci LaRIA Lab Jijel 18000 Algeria

In recent years, we have witnessed a proliferation of core network (CN) virtualization, coupled with the emergence of self deployable architectures in cellular networks. These advances provide greater flexibility and allow CN functions to be virtualized and co-located with one or more base stations. However, they introduce new challenges, such as the optimal location of CN functions based on the physical architecture. In this paper, we tackle this problem and propose a new generic and efficient solution that locates the best base station to host the CN functions, while optimizing a given performance metric (e.g., maximum flow, max-min fairness, etc.) The core of our solution relies on jointly modeling the problem as a mixed-integer Nonlinear programming (MINLP) and efficiently linearizing the nonlinear constraints. After presenting our model, we evaluate its performances, considering the global maximum flow as an optimization metric. The results showed that our joint modeling significantly reduces the run time compared to existing solutions while achieving the same optimal results. Furthermore, we highlight the genericity of our model, and we show how it can be easily adapted to handle different optimization metrics. We particularly consider some variants to address the fairness problem in conjunction with the local CN placement issue. We perform extensive simulations and discuss the obtained results. The latter allow us to derive insights regarding the tradeoff between maximum flow and fairness of proportional satisfaction, while highlighting the strengths of the proposed joint modeling.

关键词： Self deployable networks Core network virtualization Optimal placement mixed integer linear programming Constraint linearization Maximum flow Fairness

来源：评论

学校读者我要写书评

暂无评论

A new MILP model and fast heuristics for the variable-sized bin packing problem with time windows

引用

COMPUTERS & INDUSTRIAL ENGINEERING 2023年 175卷

作者： Fleszar, Krzysztof Amer Univ Beirut AUB Suliman S Olayan Sch Business OSB POB 11-0236 Beirut 11072020 Lebanon

Variable-Sized Bin Packing Problem with Time Windows (VSBPPTW) is a variant of the classical bin packing problem in which several types of bins with different sizes and costs are available, and the total cost of bins used to pack all items is minimized. Additionally, a time window is defined for each item, and the set of items packed into each bin must be time-compatible, i.e., the items in a bin must have at least one common time point within their time windows. We propose a new mixed-integer linear programming (MILP) model for VSBPPTW that (i) ensures time-compatibility by filling each bin with items from one maximal time-compatible set only and (ii) uses a compressed network flow formulation to represent the packing of items into bins under each maximal time-compatible set. New fast heuristics for VSBPPTW are also proposed to warm-start the MILP solver. Computational experiments are carried out on two sets of benchmark problem instances from the literature. We show that the new fast heuristics obtain on average much better solutions than the previously proposed fast heuristic, and the new MILP model greatly outperforms the previously proposed MILP model. While the previously proposed MILP model solves to optimality only 13% of the problem instances in the first set and none in the second, the new MILP model solves to optimality over 70% problem instances in both sets.

关键词： Bin packing Heuristics mixed integer linear programming

来源：评论

学校读者我要写书评

暂无评论

Mathematical political districting taking care of minority groups

引用

ANNALS OF OPERATIONS RESEARCH 2021年第1-2期305卷 375-402页

作者： Arredondo, Veronica Martinez-Panero, Miguel Pena, Teresa Ricca, Federica Univ Autonoma Zacatecas Zacatecas Zacatecas Mexico Univ Valladolid Valladolid Spain Univ Roma La Sapienza Rome Italy

Political districting (PD) is a wide studied topic in the literature since the 60s. It typically requires a multi-criteria approach, and mathematical programs are frequently suggested to model the many aspects of this difficult problem. This implies that exact models cannot be solved to optimality when the size of the territory is too large. In spite of this, an exact formulation can also be exploited in a heuristic framework to find at least a sub-optimal solution for large size problem instances. We study the design of electoral districts in Mexico, where the population is characterized by the presence of minority groups ("indigenous community") who have a special right to be represented in the Parliament. For this, the Mexican electoral law prescribes that a fixed number of districts must be designed to support the representation of the indigenous community. We formulate mixed integer linear programs (MILP) following these two principles, but also including the basic PD criteria of contiguity and population balance. The district map is obtained in two stages: first we produce the fixed number of indigenous districts established by the Law;then we complete the district map by forming the non-indigenous districts. This two-phase approach has two advantages: a dedicated objective function can be formulated in Phase 1 to form indigenous districts at best;in the second phase the instance size is reduced (both in the number of territorial units and in the number of districts) so that the computational effort to solve the problem is reduced as well. We test our procedure on the territory of Chiapas in Mexico and on some fictitious problem instances in which the territory is represented by a grid graph. We also compare our district map with the Institutional one currently adopted in Chiapas.

关键词： Political districting Minorities' representation Respect of administrative boundaries Graph partitioning mixed integer linear programming

来源：评论

学校读者我要写书评

暂无评论

Crossing Minimal Edge-Constrained Layout Planning using Benders Decomposition

引用

PRODUCTION AND OPERATIONS MANAGEMENT 2021年第10期30卷 3429-3447页

作者： Sudermann-Merx, Nathan Rebennack, Steffen Timpe, Christian BASF SE Data Sci Mat D-67056 Ludwigshafen Germany Karlsruhe Inst Technol KIT Inst Operat Res D-76185 Karlsruhe Germany BASF SE Adv Business Analyt D-67056 Ludwigshafen Germany

We present a new crossing number problem, which we refer to as the edge-constrained weighted two-layer crossing number problem (ECW2CN). The ECW2CN arises in layout planning of hose coupling stations at BASF, where the challenge is to find a crossing minimal assignment of tube-connected units to given positions on two opposing layers. This allows the use of robots in an effort to reduce the probability of operational disruptions and to increase human safety. Physical limitations imply maximal length and maximal curvature conditions on the tubes as well as spatial constraints imposed by the surrounding walls. This is the major difference of ECW2CN to all known variants of the crossing number problem. Such as many variants of the crossing number problem, ECW2CN is NP-hard. Because the optimization model grows fast with respect to the input data, we face out-of-memory errors for the monolithic model. Therefore, we develop two solution methods. In the first method, we tailor Benders decomposition toward the problem. The Benders subproblems are solved analytically and the Benders master problem is strengthened by additional cuts. Furthermore, we combine this Benders decomposition with ideas borrowed from fix-and-relax heuristics to design the Dynamic Fix-and-Relax Pump (DFRP). Based on an initial solution, DFRP improves successively feasible points by solving dynamically sampled smaller problems with Benders decomposition. Because the optimization model is a surrogate model for its time-dependent formulation, we evaluate the obtained solutions for different choices of the objective function via a simulation model. All algorithms are implemented efficiently using advanced features of the GuRoBi-Python API, such as callback functions and lazy constraints. We present a case study for BASF using real data and make the real-world data openly available.

关键词： optimization crossing number mixed integer linear programming Benders decomposition with direct cut calculation Benders‐ based branch‐ and‐ cut dynamic fix‐ and‐ relax pump simulation

来源：评论

学校读者我要写书评

暂无评论

Cost minimizing decisions on equipment and charging schedule for electric buses in a single depot

引用

TRANSPORTATION RESEARCH PART E-LOGISTICS AND TRANSPORTATION REVIEW 2023年 180卷

作者： Guschinsky, Nikolai Kovalyov, Mikhail Y. Pesch, Erwin Rozin, Boris Natl Acad Sci Belarus United Inst Informat Problems Minsk BELARUS Univ Siegen Siegen Germany

Combined decisions on equipment and charging schedule for electric buses (e -buses) are studied in this paper. The most representative day is considered, in which each e -bus fulfills a transfer task composed of a series of passenger transportation trips. Each trip starts and terminates at given times in the same single depot where e -buses re -charge their batteries. The problem is to determine battery variants for the e -buses, number of chargers of different types and daily cyclic charging schedule of e -buses such that a linear combination of (a) the total daily cost of the charging equipment, batteries wear and consumed energy, and (b) the total number of e -bus charging interruptions (switchings) is minimized. The constraints include an upper bound on the supplied electric power, restoration of the initial battery energy state before the next day transfer task for each e -bus and an upper bound on the maximal number of switchings for each e -bus in each depot visit over all e -buses and visits. A bi-level decomposition approach is proposed, in which decisions and constraints related to the detailed charging schedule and the number of switchings are moved to the lower-level problem. The lower level problem is formulated as mixed integer linear programming (MILP) problem. The upper-level problem is reduced to a MILP problem using linearization techniques. An exact decomposition scheme is developed for the upper-level MILP problem. A case study and comprehensive computer experiments are provided.

关键词： Electric bus Equipment selection Decomposition mixed integer linear programming Charging schedule

来源：评论

学校读者我要写书评

暂无评论

The university coursework timetabling problem: An optimization approach to synchronizing course calendars

引用

COMPUTERS & INDUSTRIAL ENGINEERING 2023年第1期184卷

作者： Mallari, Cristina Beatrice Juan, Jayne Lois San Li, Richard De La Salle Univ Dept Ind & Syst Engn Manila 1004 Philippines

In university settings, scheduling coursework over an academic term and across several courses is an extremely difficult task, owing to numerous complexities and constraints, such as the uniqueness of each student and instructor's schedules, workload limits, syllabus considerations, university policies, and the length of the academic term. In addition to the inherent difficulty, the activity is usually performed arbitrarily and with little to no coordination among the relevant decision-makers, including department chairs and faculty members. Although mathematical models have been developed to address similar educational timetabling problems, models that tackle the scheduling of coursework, in particular, are lacking. In this regard, the present study introduces the university coursework timetabling problem (UCWTP), and proposes an optimization tool as a solution approach. The UCWTP involves scheduling a set of coursework covering different courses and several course sections over an academic term such that the quality of the resulting timetable is optimized. To model the case, a multiobjective mixed integer linear programming model was formulated with constraints divided into two types, hard and soft, with the latter defining the quality of the timetable based on three dimensions: (1) compliance with curriculum requirements, (2) adherence to student workload limits, and (3) adherence to instructor workload limits. The hypothetical case considered yielded promising results as a 100% weighted satisfaction was attained, equivalent to an average improvement of 9.45% relative to multiple heuristically constructed timetables. The exact algorithm proves to be sufficiently effective as a solution approach, yielding reasonable computational times of less than 2 min for real-world university scenarios.

关键词： Educational timetabling University coursework Multi-objective optimization mixed integer linear programming Mental workload

来源：评论

学校读者我要写书评

暂无评论

Power/thermal-to-hydrogen energy storage applied to natural-gas distributed energy system in different climate regions of China

引用

ENERGY CONVERSION AND MANAGEMENT 2023年第1期283卷

作者： Ge, Yi Han, Jitian Zhu, Xiaoxuan Li, Jinyu Zhu, Wanchao Yang, Jinwen Liang, Wenxing Shandong Univ Sch Energy & Power Engn Jinan 250061 Shandong Peoples R China China Univ Petr East China Coll New Energy Qingdao 266580 Shandong Peoples R China

This paper presents a novel distributed energy system (DES) with hybrid-hydrogen energy storage, in which the proton exchange membrane electrolyzer (PEMEC) and steam reforming of methanol (SRM) are used to convert surplus power and waste heat into hydrogen. To identify the feasibility of the proposed DES in different climate regions, a case study is performed to choose a rehabilitation hospital in Harbin, Jinan, Wuhan and Guangzhou of China to explore the DES optimal configurations. The mixed integer linear programming model is established and the multi-objective optimization considering annual total cost (ATC) and annual carbon emissions (ACE) is conducted by improved version of augmented epsilon-constraint (AUGMECON2) method for system optimal config-urations. After selecting four cases among Pareto frontiers for each city, the two methods of Analytic Hierarchy Process/Shannon entropy combined with Gray Relation Analysis are performed to determine the most suitable locations. The results show that adding the SRM to DES as a hybrid-hydrogen energy storage system can improve the configuration flexibility, environmental performance and primary energy ratio compared with only -electrochemical hydrogen storage DES. The Pareto frontiers for four cities demonstrate a trade-off between ATC and ACE, and the ACE is decreased by 6.3% with ATC increased by 1.4% in Jinan. Generally, Guangzhou is the best suitable city, and Jinan and Wuhan rank second by two evaluation methods with 0.727 and 0.643 average scores, respectively. The current electricity and natural-gas prices are verified to be beneficial to Jinan to deploy the proposed DES, and Guangzhou and Wuhan present a better economic performance with the minimum ATC decreased by 11.4% and 6.58% under ideal energy prices. The results can provide useful information for hybrid-hydrogen energy storage application to DES in different climate regions.

关键词： Distributed energy system Power thermal-to-hydrogen energy storage mixed integer linear programming Multi -objective optimization Climate regions Multi -dimensional evaluation

来源：评论

学校读者我要写书评

暂无评论

A location-routing problem for local supply chains

引用

COMPUTERS & INDUSTRIAL ENGINEERING 2023年第1期183卷

作者： Soto-Mendoza, Valeria Ruiz-y-Ruiz, Efrain Garcia-Calvillo, Irma Nucamendi-Guillen, Samuel Cardona-Valdes, Yajaira Univ Autonoma Coahuila Res Ctr Appl Math Unidad Camporredondo Prolongac David Berlanga Y 16 Septiembre S-N Saltillo 25280 Coahuila Mexico Tecnol Nacl Mex IT Saltillo Div Postgrad Studies & Res Blvd Venustiano Carranza 2400 Saltillo 25280 Coahuila Mexico Univ Panamericana Fac Ingn Campus GuadalajaraAlvaro Portillo 49 Zapopan 45010 Jalisco Mexico

This study addresses a local Supply Chain problem by proposing the Collection and Delivery Location Open Routing Problem (CDLORP), a variant of the classical location-routing problem that considers both collection and distribution routes to decide where to locate facilities. Collection routes are responsible for picking up the required raw material from local suppliers, while distribution routes deliver the final product to local customers. This study is motivated by a public initiative that desires to seize the by-product generated by the agroindustrial local sector to produce and provide healthy and nutritional snacks to students in the public elementary school system in Saltillo, Coahuila, Mexico. A node-based formulation and a flow-based formulation are proposed to solve instances of the problem. The formulations are valid for the symmetric and asymmetric cases of the problem. Four families of valid inequalities from the literature are adapted for the problem and are used to implement two branch-and-cut algorithms based on the proposed formulations. Computational experiments using 42 benchmark instances of different sizes (25 to 260 vertices) are performed to assess the efficacy of the proposed formulations and algorithms. The best results are obtained by the branch-and-cut algorithm using the node-based formulation. Finally, a case study is also addressed and optimally solved with the branch-and-cut algorithm using the node-based formulation. The results obtained for the benchmark instances and the case study show that the proposed approach can solve real-life problems to develop local supply chains for new products.

关键词： Local Supply Chain Location-routing Collection and Delivery mixed integer linear programming Branch-and-cut algorithm

来源：评论

学校读者我要写书评

暂无评论

Optimization of maintenance for complex manufacturing systems using stochastic Remaining Useful Life prognostics

引用

COMPUTERS & INDUSTRIAL ENGINEERING 2023年第1期182卷

作者： He, Junkai Khebbache, Selma Anjos, Miguel F. Hadji, Makhlouf Inst Mines Telecom Telecom SudParis 9 Rue Charles Fourier F-91000 Evry France Technol Res Inst SystemX 8 Ave Vauve F-91120 Palaiseau France Univ Edinburgh Sch Math Peter Guthrie Tait Rd Edinburgh EH9 3FD Scotland

This paper leverages Remaining Useful Life (RUL) prognostic information for preventive maintenance planning in complex manufacturing factories. Such a factory consists of multiple complex systems that use redundant components as backups to ensure system availability. The purpose is to minimize production fluctuations in the factory due to maintenance or system breakdown. To achieve this, we propose a mixed-integer linear programming (MILP) model that minimizes the overall production loss. Furthermore, we incorporate random RUL decrease rates according to reliability theory and extend the MILP model using chance-constrained programming. A novel approximation method for dealing with chance constraints is proposed to solve the stochastic model and approximation properties are analyzed. Computational results show that (i) our MILP model can provide more reasonable maintenance decisions compared to the literature. (ii) Sensitivity analysis reports that RUL prognostics and thresholds significantly impact maintenance decisions. (iii) The analysis of the impacts of confidence levels in chance constraints provides decision-makers with the flexibility to adjust maintenance planning under different levels of uncertainty.

关键词： Maintenance Remaining useful life prognostic Complex manufacturing system mixed integer linear programming Chance-constrained programming

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：