检索结果-内蒙古大学图书馆

Rigorous NLP distillation models for simultaneous optimization to reduce utility and capital costs

CLEANER ENGINEERING AND TECHNOLOGY 2021年 2卷

作者： Yeoh, Keat Ping Hui, Chi Wai Hong Kong Univ Sci & Technol Dept Chem & Biol Engn Kowloon Clear Water Bay Hong Kong Peoples R China

Two non-linear programming (NLP) models with rigorous stage-by-stage MESH calculations are proposed based on the concept of bypass efficiency. The models can be used to simultaneously optimize the number of stages, feed stage location and operating parameters such as the reflux ratio and column pressure. They can also be used for simultaneous flowsheet optimization with distillation columns and heat integration, as demonstrated in a case study. The first model removes an over-specification where the enthalpy of the outlet stream is calculated using an equation-of-state. A degrees of freedom (DOF) analysis shows that the calculation is not required since the enthalpy of the outlet stream is computed from the inlet stream and equilibrium stream and the outlet temperature does not need to be known for subsequent stage calculations. The second model reduces the number of free variables by grouping the bypass efficiencies in a systematic manner. This modification reduces the model size and solution time without sacrificing accuracy or the number of unique solutions. Other than that, the pressure drop equations were improved. The improvement proved to be significant as the original equations caused all stages to be active in a case study, while the same problem was not observed with the new set of pressure drop constraints. Both proposed models had shorter solution times, smaller model size and they yielded minimized objective values 1.5-5.4% lower compared to the original bypass efficiency model.

关键词： Distillation model Rigorous non-linear programming Simultaneous optimization

来源：评论

学校读者我要写书评

暂无评论

Demand Response Model Development for Smart Households Using Time of Use Tariffs and Optimal Control-The Isle of Wight Energy Autonomous Community Case Study

引用

ENERGIES 2020年第3期13卷 541页

作者： Khanna, Sourav Becerra, Victor Allahham, Adib Giaouris, Damian Foster, Jamie M. Roberts, Keiron Hutchinson, David Fawcett, Jim Univ Portsmouth Sch Energy & Elect Engn Portsmouth PO1 3DJ Hants England Newcastle Univ Sch Engn Newcastle Upon Tyne NE1 7RU Tyne & Wear England Univ Portsmouth Sch Math & Phys Portsmouth PO1 2UP Hants England Univ Portsmouth Fac Technol Portsmouth PO1 3AH Hants England Isle Wight Council Cty Hall Newport PO30 1UD Isle Of Wight England

Residential variable energy price schemes can be made more effective with the use of a demand response (DR) strategy along with smart appliances. Using DR, the electricity bill of participating customers/households can be minimised, while pursuing other aims such as demand-shifting and maximising consumption of locally generated renewable-electricity. In this article, a two-stage optimization method is used to implement a price-based implicit DR scheme. The model considers a range of novel smart devices/technologies/schemes, connected to smart-meters and a local DR-Controller. A case study with various decarbonisation scenarios is used to analyse the effects of deploying the proposed DR-scheme in households located in the west area of the Isle of Wight (Southern United Kingdom). There are approximately 15,000 households, of which 3000 are not connected to the gas-network. Using a distribution network model along with a load flow software-tool, the secondary voltages and apparent-power through transformers at the relevant substations are computed. The results show that in summer, participating households could export up to 6.4 MW of power, which is 10% of installed large-scale photovoltaics (PV) capacity on the island. Average carbon dioxide equivalent (CO(2)e) reductions of 7.1 ktons/annum and a reduction in combined energy/transport fuel-bills of 60%/annum could be achieved by participating households.

关键词： demand response electric vehicle solar photovoltaics battery optimisation non-linear programming sustainability

来源：评论

学校读者我要写书评

暂无评论

A Generalized Economic Order Quantity Inventory Model with Shortage: Case Study of a Poultry Farmer

引用

ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2019年第3期44卷 2653-2663页

作者： Nobil, Amir Hossein Sedigh, Amir Hosein Afshar Eduardo Cardenas-Barron, Leopoldo Islamic Azad Univ Fac Ind & Mech Engn Qazvin Branch Qazvin Iran Univ Otago Dept Informat Sci Dunedin New Zealand Tecnol Monterrey Sch Sci & Engn E Garza Sada 2501 Sur Monterrey 64849 NL Mexico

We consider an EOQ inventory model for growing items, wherein the value and size of items increase during time, some instances of these items are livestock, fish, and poultry. The main difference between this inventory system and older ones is weight increment of products during stocking without buying more. This paper studies an inventory system of poultries that new-born items are fed to reach the ideal weight for consumers. In this study, based on the consumers' preference of fresh foods over frozen items, we assume that shortage is permitted and consumers wait for fresh items when company pays some additional penalties, i.e., the shortage is fully backordered. On the other hand, for each cycle, the producer must prepare the place in terms of hygiene conditions;thus, a setup time per cycle is considered. The aim of this study is to obtain optimum system solution, such that total costs, including setup, purchasing, holding, feeding, and shortage, are minimized. To do so, we employ mathematical measures to approximate growing rates and model the system as a non-linear programming. To solve the obtained optimization model, we employ hessian matrix to obtain optimal solution for this inventory system. The proposed EOQ inventory model helps poultry industries in Iran to optimize their system considering costs and permissible shortage, and it can be employed in other countries. Finally, we provide a numerical example and its sensitivity analysis, plus some potential future directions.

关键词： Inventory management Economic order quantity Growing items non-linear programming Permissible shortage Poultry

来源：评论

学校读者我要写书评

暂无评论

High-Fidelity Harmonic Generation in Optical Micro-Resonators Using BFGS Algorithm

引用

MICROMACHINES 2020年第7期11卷 686-686页

作者： Asirim, Ozum Emre Yolalmaz, Alim Kuzuoglu, Mustafa Middle East Tech Univ Dept Elect & Elect Engn TR-06800 Ankara Turkey Middle East Tech Univ Micro & Nanotechnol Program TR-06800 Ankara Turkey

Harmonic generation is an attractive research field that finds a variety of application areas. However, harmonic generation within a medium of micron-scale interaction length limits the magnitude of nonlinear coupling and leads to poor harmonic generation efficiency. In this study, we present a constrained non-linear programming approach based on the Quasi-Newton Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm to obtain high-fidelity harmonic generation in optical micro-resonators. Using this approach, one can achieve high-intensity harmonic generation in a simple Fabry-Perot type optical micro-resonator. The generation of super-intense harmonics at a typical ultraviolet (UV)-ablation frequency of 820 THz and at pure yellow-light (515 THz) is investigated in particular. Moreover, we achieved more than 98% accuracy compared to well-known theoretical results. Our approach enables the design of highly efficient microscale harmonic generators to be used in integrated photonic devices.

关键词： harmonic generation non-linear wave mixing non-linear programming micro-resonator

来源：评论

学校读者我要写书评

暂无评论

Theoretical Foundations of the Method of Designing a Clothoid Track with Approximation of Succession of Points 5th

Theoretical Foundations of the Method of Designing a Clothoi...

引用

5th National Scientific and Practical Conference on Perspectives on the Use of New Information and Communication Technology (ICT) in the Modern Economy

作者： Skrypnikov, Aleksey V. Kozlov, Vyacheslav G. Belyaev, Alexandr N. Chernyshova, Elena V. Voronezh State Univ Engn Technol Voronezh Russia Voronezh State Agr Univ Voronezh Russia

ISBN: (纸本)9783319908359;9783319908342

The experience of designing a track with the use of the basic elements method showed its high effectiveness with the possibilities for the further improvement of the process of the automatized designing for the purpose of full elimination of the stage of graphical elaboration of the track and automatic consideration of all requirements set to it. For the purpose of realization of these possibilities, the issues of designing a clothoid track by approximation of succession of points of a sketch line with application of the methods of non-linear programming were viewed (method of approximation of succession of points). This method sets the task of the best approximation of the track to the set succession of point of the sketch line.

关键词： Designing Approximation Clothoid track non-linear programming Forest roads

来源：评论

学校读者我要写书评

暂无评论

Mathematical programs with vanishing constraints: constraint qualifications, their applications, and a new regularization method

引用

OPTIMIZATION 2019年第2-3期68卷 509-538页

作者： Dussault, J. -P. Haddou, M. Migot, T. Univ Sherbrooke Fac Sci Dept Informat Sherbrooke PQ Canada Univ Rennes INSA Rennes CNRS IRMAR UMR 6625 F-35000 Rennes France Univ Guelph Dept Math & Stat Guelph ON Canada

We propose a new family of relaxation schemes for mathematical programs with vanishing constraints that extend the relaxation of Hoheisel, Kanzow & Schwartz from 2012. We discuss the properties of the sequence of relaxed non-linear programs as well as stationary properties of limiting points. Our relaxation schemes have the desired property of converging to an M-stationary point. A main advantage of this new method is to converge to an S-stationary point satisfying MPVC-LICQ for a large class of problem. We also study MPVC constraint qualification connected to this study and prove convergence of the method under the new MPVC-CRSC. Additionally, we obtain the new MPVC-wGCQ and prove that it is the weakest MPVC constraint qualification.

关键词： non-linear programming MPCC MPEC MPVC relaxation methods

来源：评论

学校读者我要写书评

暂无评论

non-linear Localization Algorithm Based on Newton Iterations

引用

Journal on Internet of Things 2020年第4期2卷 129-134页

作者： Jianfeng Lu Guirong Fei Institute of Information Technology Taizhou Polytechnic CollegeTaizhou225300China

In order to improve the performance of time difference of arrival(TDOA)localization,a nonlinear least squares algorithm is proposed in this ***,based on the criterion of the minimized sum of square error of time difference of arrival,the location estimation is expressed as an optimal problem of a non-linear ***,an initial point is obtained using the semi-definite *** finally,the location is extracted from the local optimal solution acquired by Newton *** results show that when the number of anchor nodes is large,the performance of the proposed algorithm will be significantly better than that of semi-definite programming approach with the increase of measurement noise.

关键词： Wireless localization non-linear programming time difference of arrival newton Iteration

来源：评论

学校读者我要写书评

暂无评论

Design of a new tensegrity cantilever structure

引用

COMPOSITE STRUCTURES 2020年 243卷 112188-112188页

作者： Ma, Shuo Chen, Muhao Skelton, Robert E. Zhejiang Univ Coll Civil Engn & Architecture Hangzhou 310058 Peoples R China Texas A&M Univ Dept Aerosp Engn College Stn TX 77840 USA

This study mainly focuses on the design of a new cantilever structure and its minimal mass optimization subject to yield and buckling constraints. Given a vertical force in a constant distance from a vertical wall, the minimal mass design of a two elements structure with and without anchorage length limitation of the wall is first studied. To further reduce the total structural mass of, a sector cantilever structure is proposed, and the advantage of choosing equal bar length and connecting strings to the center of a circle is proved. Given finite anchorage length of the wall, a tailored sector cantilever structure with finite anchorage length is proposed. Minimal mass design of the sector cantilever with and without anchorage length constraint can be obtained by processing a constrained nonlinear optimization of shape parameters. Considering the penalty of joint mass, the optimal complexity of the sector cantilever will decrease as the penalty coefficient increases. Numerical results are given to show the efficiency of the proposed cantilever structures in saving mass.

关键词： Minimal mass Tensegrity system Cantilever structure non-linear programming Infinite/finite anchorage length

来源：评论

学校读者我要写书评

暂无评论

Optimization of Frequency Controller Parameters of a BESS by considering Rate of Change Constraints

Optimization of Frequency Controller Parameters of a BESS by...

引用

IEEE Milan PowerTech Conference

作者： Sanchez, Francisco Gonzalez-Longatt, Francisco Loughborough Univ Ctr Renewable Energy Syst Technol CREST Loughborough Leics England

ISBN: (纸本)9781538647226

This paper presents a methodology to optimize the parameters of the frequency controller installed in a battery energy storage system (BESS) to minimize frequency deviation considering electricity system operator (ESO) imposed rate of change constraints. The problem is formulated with a non-linear programming (NLP) structure and the exterior penalty function (EPF) method is applied to solve it efficiently. The impact of the location of the BESS on the frequency nadir is quantified by simulations in a medium voltage (MV) distribution network benchmark with a high proportion of distributed energy resources (DER). Simulations are performed with detailed dynamic models in DIgSILENT (R) Power Factory (TM) in combination with Python for data analysis and manipulation. Simulation results show the suitability of the proposed approach.

关键词： Battery energy storage system distributed energy resources non-linear programming rate of change of frequency system frequency response

来源：评论

学校读者我要写书评

暂无评论

Optimization Methods for Evaluating PV Hosting Capacity of Distribution Circuits 46

Optimization Methods for Evaluating PV Hosting Capacity of D...

引用

IEEE 46th Photovoltaic Specialists Conference (PVSC)

作者： Jothibasu, Suma Santoso, Surya Dubey, Anamika Elect Power Res Inst Palo Alto CA 94304 USA Univ Texas Austin Dept Elect & Comp Engn Austin TX 78712 USA Washington State Univ Sch Elect Engn & Comp Sci Pullman WA 99164 USA

ISBN: (纸本)9781728104942

As today's distribution grid is experiencing increased rooftop solar installations, there is growing interest in evaluating the PV hosting capacity (HC) of the grid. Since, predicting the exact size and location of potential PV installations is not feasible at the distribution grid planning phase, a stochastic method is employed to choose a finite number of combinations of possible PV size and location. As a result, the calculated PV HC is a range of total PV capacity in MW that a circuit can accommodate and not a single value. Additionally, the calculated PV HC range is not unique;it varies with the PV distribution considered for the analysis. This paper proposes an optimal power flow based formulation to find the maximum PV capacity in MW that can be accommodated in a given distribution grid. The PV HC values are evaluated for IEEE 123 bus circuit by the proposed method and the results are compared with the conventional approach. It is observed that the results of the optimal power flow method is unique and can act as the upper bound for the stochastic PV HC analysis.

关键词： Distributed photovoltaic cells Voltage Smart Inverter Optimization non-linear 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：