检索结果-内蒙古大学图书馆

Comprehensive energy footprint benchmarking of commercial electrified powertrains

APPLIED ENERGY 2023年第1期345卷

作者： Anwar, Hamza Vishwanath, Aashrith Ahmed, Qadeer Chunodkar, Apurva Ohio State Univ Ctr Automot Res 930 Kinnear Rd Columbus OH 43212 USA Cummins Tech Ctr 1900 McKinley Ave Columbus IN 47201 USA

This work presents a comprehensive energy management framework applied to electrified commercial powertrains with in-depth energy footprint analysis. We use our recently proposed algorithm, validated real -world powertrain system models, and Pareto-optimal analysis to optimize fuel consumption and harmful pollutant emissions. The approach involves dynamic optimization of 13 states and 4 control levers capturing complex subsystem interactions in parallel P2 and series range-extender commercial medium-duty electrified trucks. These subsystems exhibit vehicular (eco-driving), thermal, electrical, and mechanical dynamics at different time scales, and contain kinematic and combinatorial constraints, integer-and real-valued variables, interpolated look-up tables, and data maps. A Pareto-optimal solution is found by carefully optimizing fuel and NOx emissions to understand the energy footprint. Presented results exhibit rich powertrain behavior to unearth up to 6% improvement in energy demand, 2% in fuel economy and 18% in pollutant NOx reduction when compared to Dynamic programming baseline from a coarsely modeled powertrain system. Furthermore, internal energy flow in the powertrains is analyzed to benchmark the optimal energy consumption and realize the multi-objective trade-off. Finally, a transient study problem is presented comparing cold versus warm after-treatment start conditions. It optimizes engine switching, eco-driving, and powersplit controls revealing adequate dynamic response and complex system interactions.

关键词： Optimal energy management Eco-driving Powertrain control mixed-integer nonlinear programming Fuel and NOx emissions minimization

来源：评论

学校读者我要写书评

暂无评论

A green cogeneration microgrid composed of water-source heat pumps, a gravity energy storage, and a bio-fueled gas turbine: Design and techno-economic optimization

引用

SUSTAINABLE CITIES AND SOCIETY 2023年 95卷

作者： Taheri, Bahman Jabari, Farkhondeh Foroud, Asghar Akbari Semnan Univ Elect & Comp Engn Fac Semnan Iran Niroo Res Inst NRI Power Syst Operat & Planning Res Dept Tehran Iran

Rapid population and economic growth, democratization, decarbonization, deregulation, decentralization, and digitization (5D) of energy sector, transformation in lifestyle, as well as subsidized supply of petroleum products contribute to peak electricity utilization. In summer, limited power generation of thermal units have caused an urgent need to storages and renewable energy sources (RES). To mitigate pollutants emitted from generation facilities, nearly zero-energy buildings are created using RES and energy storage technologies. Hence, this paper presents a green combined cooling and power (CCP) generation system for industrial applications. A bio-fueled gas turbine cycle is selected to produce power for supplying both electrical demand and energy requirement of cooling loads. Some water-source heat pumps (WSHPs) are economically dispatched to procure cooling loads. A gravity energy storage (GES) is optimally scheduled to charge surplus electricity by pumping water and lifting a piston within a container and discharge it during peak periods by falling the piston and returning the high-pressure water into a hydro-turbine. A mixed-integer nonlinear programming problem is modeled to find the optimum operating point of the proposed plant minimizing the total energy cost. Simulations are conducted on a real industrial end-user with four WSHPs under two cases without and with cooperation of GES.

关键词： Water-source heat pumps (WSHPs) Gravity energy storage (GES) Bio-fueled Brayton cycle Economic dispatch mixed-integer nonlinear programming (MINLP)

来源：评论

学校读者我要写书评

暂无评论

Minotaur: a mixed-integer nonlinear optimization toolkit

引用

MATHEMATICAL programming COMPUTATION 2021年第2期13卷 301-338页

作者： Mahajan, Ashutosh Leyffer, Sven Linderoth, Jeff Luedtke, James Munson, Todd Indian Inst Technol Ind Engn & Operat Res Mumbai 400076 Maharashtra India Argonne Natl Lab Math & Comp Sci Div Lemont IL 60439 USA Univ Wisconsin Dept Ind & Syst Engn Madison WI 53706 USA

We present a flexible framework for general mixed-integer nonlinear programming (MINLP), called Minotaur, that enables both algorithm exploration and structure exploitation without compromising computational efficiency. This paper documents the concepts and classes in our framework and shows that our implementations of standard MINLP techniques are efficient compared with other state-of-the-art solvers. We then describe structure-exploiting extensions that we implement in our framework and demonstrate their impact on solution times. Without a flexible framework that enables structure exploitation, finding global solutions to difficult nonconvex MINLP problems will remain out of reach for many applications.

关键词： mixed-integer nonlinear programming Global optimization Software

来源：评论

学校读者我要写书评

暂无评论

Planning of distributed ventilation systems for energy-efficient buildings by discrete optimisation

引用

JOURNAL OF BUILDING ENGINEERING 2023年 68卷

作者： Mueller, Tim M. Sachs, Marlene Breuer, Julius H. P. Pelz, Peter F. Tech Univ Darmstadt Fluid Syst Otto Berndt Str 2 D-64287 Darmstadt Germany

The EU's climate targets are increasingly affecting the building sector. Energy-efficient buildings should therefore be built as airtight as possible in order to meet these targets - ventilation systems are necessary to ensure a comfortable indoor climate. In the planning of ventilation systems, the placement, wiring and operation of the fans, among other things, must be considered. If, instead of the conventional planning for the maximum load case, the partial load scenarios are included, oversizing is reduced and energy efficiency is increased. In addition, there are new ventilation approaches that include distributed components in the central duct network and thus offer further opportunities to increase the energy efficiency of the systems. If one now considers multiple load cases and allows distributed components in the design, the number of combinations exceeds any human manageable amount and the human made design decision becomes far from optimal as a result. Therefore, in this paper a method is presented that uses mathematical optimisation techniques to control the complexity and support the design. The planning task is modeled techno-economically as a minimisation problem with respect to life-cycle costs (mixed-integer nonlinear Program) and solved with discrete optimisation methods. The approach is then tested on a case study, with which savings of 22% in life-cycle costs are achieved while reducing energy consumption by 28%. Furthermore, the embedding in the real planning process is considered and shown that the division into several planning phases has a negative impact on the efficiency of the ventilation system. These results show that increasing the complexity of the planning task and modelling and solving it using discrete optimisation methods allows for a huge increase in the efficiency of the ventilation system.

关键词： Distributed ventilation system Discrete optimisation Life -cycle cost optimisation mixed-integer nonlinear programming

来源：评论

学校读者我要写书评

暂无评论

nonlinear topology optimization of District Heating Networks: A benchmark of a mixed-integer and a density-based approach

引用

ENERGY 2023年第PartB期278卷

作者： Wack, Yannick Serra, Sylvain Baelmans, Martine Reneaume, Jean-Michel Blommaert, Maarten Katholieke Univ Leuven Dept Mech Engn Celestijnenlaan 300 POB 2421 B-3001 Leuven Belgium Univ Pau & Pays Adour UPPA E2S LaTEP Pau France Flemish Inst Technol Res VITO Boeretang 200 B-2400 Mol Belgium EnergyVille Thor Pk 3600 Genk B-8310 Genk Belgium

The widespread use of optimization methods in the design phase of District Heating Networks is currently limited by the availability of scalable optimization approaches that accurately represent the network. In this paper, we benchmark two different approaches to nonlinear topology optimization of District Heating Networks in terms of computational cost and optimality gap. We compare a combinatorial approach, which directly solves a mixed-integer nonlinear program, against a density-based approach. This density-based approach relaxes the integer constraint on pipe placement and ensures near-discrete topologies through penalization. The benchmark shows subquadratic scaling of the computational cost for the density-based approach, making it tractable for large problems, while the combinatorial approach scales exponentially. The combinatorial approach took 29 h to optimize a network for a neighborhood of about 600 streets, compared to 35 min for the density-based method. Optimality gap analysis indicates that resolving the integer constraint on pipe placement does not necessarily lead to a superior design, while making the optimization of large practical problems intractable. In contrast, the scaling of the density-based approach remains tractable for large problems. Further study of the optimality gap highlights the importance of consciously choosing initialization strategies when deciding to solve the nonlinear topology optimization problem.

关键词： District Heating Networks Topology optimization mixed-integer nonlinear programming Benchmark

来源：评论

学校读者我要写书评

暂无评论

Relaxation approaches for nonlinear sparse optimization problems

引用

OPTIMIZATION 2024年第10期73卷 3237-3258页

作者： Steffensen, Sonja Rhein Westfal TH Aachen Inst Geometrie & Prakt Math Aachen Germany

In many recent applications, sparse solutions of the optimization problems are favoured over non-sparse solutions with comparable objective values. A standard method to induce the sparsity of the solution is based on the use of the l(0) norm in the objective. However, if the underlying optimization problem is nonlinear, the solution of the nonlinear (sparse) l(0)optimization problem is difficult. Therefore, it is often approximated using the convex l(1)-norm although this can lead to suboptimal solutions for the sparsity of the solution. In this paper, we follow another direction. We present exact reformulations (with respect to the l(0) norm) and their relaxations leading to standard nonlinear but nonconvex programmes. Wediscuss and relate the relations between the different reformulations with repect to the original problem. We accompany our theoretical results by some numerical tests using randomly generated datasets.

关键词： Sparse optimization nonlinear programming complementarity constraints mixed-integer nonlinear programming

来源：评论

学校读者我要写书评

暂无评论

Enabling Research through the SCIP Optimization Suite 8.0

引用

ACM TRANSACTIONS ON MATHEMATICAL SOFTWARE 2023年第2期49卷 22-22页

作者： Bestuzheva, Ksenia Besancon, Mathieu Chen, Wei-Kun Chmiela, Antonia Donkiewicz, Tim Van Doornmalen, Jasper Eifler, Leon Gaul, Oliver Gamrath, Gerald Gleixner, Ambros Gottwald, Leona Graczyk, Christoph Halbig, Katrin Hoen, Alexander Hojny, Christopher Van Der Hulst, Rolf Koch, Thorsten Luebbecke, Marco Maher, Stephen J. Matter, Frederic Muehmer, Erik Mueller, Benjamin Pfetsch, Marc E. Rehfeldt, Daniel Schlein, Steffan Schloesser, Franziska Serrano, Felipe Shinano, Yuji Sofranac, Boro Turner, Mark Vigerske, Stefan Wegscheider, Fabian Wellner, Philipp Weninger, Dieter Witzig, Jakob Zuse Inst Berlin Dept AIS2T Takustr 7 D-14195 Berlin Germany Beijing Inst Technol Sch Math & Stat 5 Zhongguancun South St Beijing 100081 Peoples R China Rhein Westfal TH Aachen Lehrstuhl Operat Res Kackertstr 7 D-52072 Aachen Germany Eindhoven Univ Technol Dept Math & Comp Sci POB 513 NL-5600 MB Eindhoven Netherlands Zuse Inst Berlin Dept ZIB AIS2T & I2DAMO GmbH Englerallee 19 D-14195 Berlin Germany Friedrich Alexander Univ Erlangen Nurnberg Dept Data Sci Cauerstr 11 D-91058 Erlangen Germany Univ Twente Dept Discrete Math & Math Programming POB 217 NL-7500 AE Enschede Netherlands Tech Univ Berlin Chair Software & Algorithms Discrete Optimizat Str 17 Juni 135 D-10623 Berlin Germany ZIB Dept A2IM Takustr 7 D-14195 Berlin Germany Univ Exeter Coll Engn Math & Phys Sci Harrison BldgStreatham CampusN Pk Rd Exeter EX4 4QF England Tech Univ Darmstadt Fachbereich Math Dolivostr 15 D-64293 Darmstadt Germany Zuse Inst Berlin Dept A2IM Takustr 7 D-14195 Berlin Germany Tech Univ Berlin Berlin Germany Zuse Inst Berlin GAMS Software GmbH Dept AIS2T Takustr 7 D-14195 Berlin Germany

The SCIP Optimization Suite provides a collection of software packages for mathematical optimization centered around the constraint integer programming framework SCIP. The focus of this article is on the role of the SCIP Optimization Suite in supporting research. SCIP's main design principles are discussed, followed by a presentation of the latest performance improvements and developments in version 8.0, which serve both as examples of SCIP's application as a research tool and as a platform for further developments. Furthermore, this article gives an overview of interfaces to other programming and modeling languages, new features that expand the possibilities for user interaction with the framework, and the latest developments in several extensions built upon SCIP.

关键词： Constraint integer programming linear programming mixed-integer linear programming mixed-integer nonlinear programming optimization solver branch-and-cut branch-and-price column generation parallelization mixed-integer semidefinite programming

来源：评论

学校读者我要写书评

暂无评论

Switched NMPC for epidemiological and social-economic control objectives in SIR-type systems

引用

ANNUAL REVIEWS IN CONTROL 2023年第1期56卷

作者： Sereno, J. E. D'Jorge, A. Ferramosca, A. Hernandez-Vargas, E. A. Gonzalez, A. H. CONICET UNL Inst Technol Dev Chem Ind INTEC Guemes 3450 RA-3000 Santa Fe Argentina Univ Bergamo Dept Management & Informat & Prod Engn Bergamo Italy Univ Idaho Dept Math & Stat Sci Moscow ID USA

Several optimal control strategies have recently been developed to minimize the infected peak prevalence or the epidemic final size. Although these two indexes are critical to assess any control policy tending to mitigate an epidemic by means of non-pharmaceutical measures, they are usually considered separately and, in general, no consensus has been reached about how to simultaneously handle them in a simple and realistic way (i.e., accounting for the limitations in the control actions, avoiding new cycles of infections or reboundings, considering side effects, etc.) Here, based on a theoretical dynamical analysis of SIR-type models, a realistic nonlinear model predictive control strategy is proposed. Apart from minimizing the epidemic final size and keeping the infected peak prevalence under an established value, the controller accounts for feedback uncertainty and different actuator constraints, such as a limited number of social distancing policies, which may remain active for a minimal and a maximal time interval. Several simulations considering different SIR-type models illustrate the benefits of the proposal.

关键词： Switched model predictive control Epidemic control mixed-integer nonlinear programming Discrete control actions

来源：评论

学校读者我要写书评

暂无评论

Reconstruction of delay differential equations via learning parameterized dictionary

引用

PHYSICA D-nonlinear PHENOMENA 2023年第1期446卷

作者： Wu, Yuqiang Huazhong Univ Sci & Technol Sch Artificial Intelligence & Automat Wuhan Hubei Peoples R China

Reconstructing the governing equations of unknown systems plays an important role in physics. Sparse modeling methods, such as sparse identification of nonlinear dynamical systems (SINDy), provide a very good framework to tackle this problem. However, SINDy struggles with discovering delay differential equations (DDEs) due to the curse of dimensionality in the candidate dictionary. That is, each possible discrete delay term in the dictionary should be regarded as an independent basis element, which makes the combination of exhaustive discrete delay terms blow up. To deal with the curse of dimensionality and further reconstruct DDEs, a variant method of SINDy is presented in this paper in which a parameterized dictionary is proposed. In the parameterized dictionary, undetermined parameter variables are included in the candidate function to cover a wide range of different functions. Then, the reconstruction problem is reformulated as mixed-integer nonlinear programming (MINLP) and solved by a bi-level algorithm in which the binary version and the continuous version of particle swarm optimization (PSO) are respectively adopted in two levels. Simulation experiments are performed in 5 test systems including 3 well-known chaotic DDEs such as Mackey-Glass system. The results validate the effectiveness of the presented method.

关键词： Sparse identification of nonlinear dynamical systems (SINDy) Delay differential equations (DDEs) Particle swarm optimization (PSO) Parameterized dictionary mixed-integer nonlinear programming (MINLP)

来源：评论

学校读者我要写书评

暂无评论

A new coordination scheme of directional overcurrent and distance protection relays considering time-voltage-current characteristics

引用

INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS 2023年第1期150卷

作者： Assouak, Asma Benabid, Rabah USTHB Elect Engn Dept LSEI Bab Ezzouar 16025 Algeria CRNB Elect Engn Dept Djelfa 17200 Algeria USTHB Elect Engn Dept Elect & Ind Syst Lab LSEI Bab Ezzouar 16025 Algeria

The power transmission systems are mainly protected by distance relays (DisRs) as a primary protection and directional overcurrent relays (DOCRs) as a backup protection. These two types of relays have a different operation principle that, sometimes, leads to miscoordination problems. In this paper, a new approach for DOCRs and DisRs coordination considering the DOCRs time-voltage-current characteristic (TVC-C) is proposed to fully eliminate the miscoordination problems found in the already published works. The coordination problem is formulated as a mixed-integer nonlinear programming (MINLP) considering a new proposed objective function. Furthermore, two new decision variables related to TVC-Cs are proposed namely: the type and the voltage control variable. An enhanced version of the hybrid GSA-SQP method is proposed to solve the developed opti-mization problem. In order to check the applicability of the proposed relays coordination method on small and large and more complex systems, the IEEE 9-bus and IEEE 39-bus are used for this task. The obtained results are compared with the published works which show the superiority of the proposed method in terms of satisfaction of all coordination constraints.

关键词： Time-voltage-current characteristic mixed-integer nonlinear programming Distance relay Directional overcurrent relay Protection coordination Electric power system

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：