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Passive shimming based on mixed integer programming for MRI magnet

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Science China(Technological Sciences) 2013年第5期56卷 1208-1212页

作者： YOU XiaoFei WANG Zheng ZHANG XiaoBing YANG WenHui SONG Tao Institute of Electrical Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

A mathematical model based on mixed integer programming is presented in this paper for the passive shimming of magnet in magnetic resonance imaging(MRI) *** this model,the magnetic field inhomogeneity tolerance and the central value of the magnetic field after shimming are programmed together with the volume of each shim piece as the variables,which increases the degree of freedom and guarantees a better *** magnetic field inhomogeneity tolerance after shimming with a weighting coefficient and the total volume of shim pieces are both contained in the objective function of the *** assigning different values to the weighting coefficient in the objective function,different shimming plans with different emphases can be obtained.A simulation test has been carried out on a small permanent magnet with frame *** solutions are given and compared in this paper,which indicates that a practical shimming plan can be obtained quickly by solving this model.

关键词： mixed integer programming passive shimming magnetic resonance imaging (MRI)

AN EXTRACTION ALGORITHM FOR A SET OF ELEMENTARY SIPHONS BASED ON mixed-integer programming

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Journal of Systems Science and Systems Engineering 2012年第1期21卷 106-125页

作者： Shaoyong LI Zhiwu LI Hesuan HU Abdulrahman AI-AHMARI Aimin AN School of Electro-Mechamcal Engmeermg Xidian University Xi＇ an 710071 P. R. China School of Ctvil Engmeertng Lanzhou University of Technology Lanzhou 730050 P. R. China College of Engineering King Saud University Riyadh 11421 Saudi Arabia

Elementary siphons are useful in the development of a deadlock prevention policy for a discrete event system modeled with Petri nets. This paper proposes an algorithm to iteratively extract a set of elementary siphons in a class of Petri nets, called system of simple sequential processes with resources （S3pR）. At each iteration, by a mixed-integer programming （MIP） method, the proposed algorithm finds a maximal unmarked siphon, classifies the places in it, extracts an elementary siphon from the classified places, and adds a new constraint in order to extract the next elementary siphon. This algorithm iteratively executes until no new unmarked siphons can be found. It finally obtains a unique set of elementary siphons and avoids a complete siphon enumeration. A theoretical analysis and examples are given to demonstrate its efficiency and practical potentials.

关键词： Petri net flexible manufacturing system deadlock prevention mixed integer programming elementary siphon

A mixed-integer programming Formulation for a Simplified Model of the Double Row Layout Problem

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Wuhan University Journal of Natural Sciences 2023年第5期28卷 433-440页

作者： GUAN Jian LIN Geng FENG Huibin RUAN Zhiqiang Modern Educational Technology Center Minjiang UniversityFuzhou 350121FujianChina College of Mathematics and Data Science Minjiang UniversityFuzhou 350121FujianChina College of Computer and Control Engineering Minjiang UniversityFuzhou 350121FujianChina

The double row layout problem(DRLP)is to assign facilities on two rows in parallel so that the total cost of material handling among facilities is *** it is vital to save cost and enhance productivity,the DRLP plays an important role in many application ***,it is very hard to handle the DRLP because of its complex *** this paper,we consider a new simplified model for the DRLP(SM-DRLP)and provide a mixed integer programming(MIP)formulation for *** continuous decision variables of the DRLP are divided into two parts:start points of double rows and adjustable clearances between adjacent *** former one is considered in the new simplified model for the DRLP with the purpose of maintaining solution quality,while the latter one is not taken into account with the purpose of reducing computational *** evaluate its performance,our SM-DRLP is compared with the model of a general DRLP and the model of another simplified *** experimental results show the efficiency of our proposed model.

关键词： facility layout mixed integer programming double row layout problem production optimization manufacturing design

A NEW GLOBAL OPTIMIZATION ALGORITHM FOR mixed-integer QUADRATICALLY CONSTRAINED QUADRATIC FRACTIONAL programming PROBLEM

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Journal of Computational Mathematics 2024年第3期42卷 784-813页

作者： Bo Zhang Yuelin Gao Xia Liu Xiaoli Huang School of Civil and Hydraulic Engineering School of Mathematics and StatisticsNingxia UniversityYinchuan 750021China School of Mathematics and Information Science North Minzu UniversityYinchuan 750021China Ningxia Province Key Laboratory of Intelligent Information and Data Processing Yinchuan 750021China School of Mathematics and Statistics Ningxia UniversityYinchuan 750021China

The mixed-integer quadratically constrained quadratic fractional programming(MIQCQFP)problem often appears in various fields such as engineering practice,management science and network ***,most of the solutions to such problems are often designed for their unique *** paper puts forward a new global optimization algorithm for solving the problem *** first convert the MIQCQFP into an equivalent generalized bilinear fractional programming(EIGBFP)problem with integer ***,we linearly underestimate and linearly overestimate the quadratic functions in the numerator and the denominator respectively,and then give a linear fractional relaxation technique for EIGBFP on the basis of non-negative *** that,combining rectangular adjustment-segmentation technique and midpointsampling strategy with the branch-and-bound procedure,an efficient algorithm for solving MIQCQFP globally is ***,a series of test problems are given to illustrate the effectiveness,feasibility and other performance of this algorithm.

关键词： Global optimization Branch and bound Quadratic fractional programming mixed integer programming

Closed-loop scheduling optimization strategy based on particle swarm optimization with niche technology and soft sensor method of attributes-applied to gasoline blending process

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Chinese Journal of Chemical Engineering 2023年第9期61卷 43-57页

作者： Jian Long Kai Deng Renchu He Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghaiChina Engineering Research Center of Process System Engineering Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Gasoline blending scheduling optimization can bring significant economic and efficient benefits to ***,the optimization model is complex and difficult to build,which is a typical mixed integer nonlinear programming(MINLP)*** the large scale of the MINLP model,in order to improve the efficiency of the solution,the mixed integer linear programming-nonlinear programming(MILP-NLP)strategy is used to solve the *** paper uses the linear blending rules plus the blending effect correction to build the gasoline blending model,and a relaxed MILP model is constructed on this *** particle swarm optimization algorithm with niche technology(NPSO)is proposed to optimize the solution,and the high-precision soft-sensor method is used to calculate the deviation of gasoline attributes,the blending effect is dynamically corrected to ensure the accuracy of the blending effect and optimization results,thus forming a prediction-verification-reprediction closed-loop scheduling optimization strategy suitable for engineering *** optimization result of the MILP model provides a good initial *** fixing the integer variables to the MILPoptimal value,the approximate MINLP optimal solution can be obtained through a NLP *** above solution strategy has been successfully applied to the actual gasoline production case of a refinery(3.5 million tons per year),and the results show that the strategy is effective and *** optimization results based on the closed-loop scheduling optimization strategy have higher *** with the standard particle swarm optimization algorithm,NPSO algorithm improves the optimization ability and efficiency to a certain extent,effectively reduces the blending cost while ensuring the convergence speed.

关键词： Blend Optimization algorithm Neural networks Particle swarm optimization mixed integer programming

MIP FORMULATIONS AND HEURISTICS FOR SOLVING PARALLEL BATCHING PROBLEMS

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Journal of Systems Science & Complexity 2010年第5期23卷 884-895页

作者： Udo BUSCHER Liji SHEN Chair of Industrial Management Department of Business Administration and Economics Dresden University of Technology ( Technische Universitaet Dresden) Dresden 01062 Germany.

This paper addresses the scheduling problem involving batch processing machines, which is Mso known as parallel batching in the literature. The presented mixed integer programming formulation first provides an elegant model for the problem under study. Fhrthermore, it enables solutions to the problem instances beyond the capability of exact methods developed so far. In order to alleviate computational burden, the authors propose MIP-based heuristic approaches which balance solution quality and computing time.

关键词： Batching decisions mixed integer programming scheduling.

Graph Computing Based Security Constrained Unit Commitment in Hydro-thermal Power Systems Incorporating Pumped Hydro Storage

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CSEE Journal of Power and Energy Systems 2021年第3期7卷 485-496页

作者： Longfei Wei Guangyi Liu Shen Yan Renchang Dai Yachen Tang Hitachi ABB Power Grids San JoseCAUSA School of Electrical Engineering Xi'an University of TechnologyXi'anChina Department of Industrial and Enterprise Systems Engineering University of Illinois at Urbana-ChampaignChampaignILUSA Puget Sound Energy BellevueWAUSA Envision Digital Inc. Redwood CityCAUSA

This paper proposes a graph computing based mixed integer programming(MIP)framework for solving the security constrained unit commitment(SCUC)problem in hydro-thermal power systems incorporating pumped hydro storage(PHS).The proposed graph computing-based MIP framework considers the economic operations of thermal units,cascade hydropower stations and PHS stations,as well as their technical impacts towards the network ***,the hydro-thermal power system data and unit information are stored in a graph structure with nodes and edges,which enables nodal and hierarchical parallel computing for the unit commitment(UC)solution calculation and network security analysis.A MIP model is then formulated to solve the SCUC problem with the mathematical models of thermal units,cascade hydropower stations and PHS *** addition,two optimization approaches including convex hull reformulation(CHR)and special ordered set(SOS)methods are introduced for speeding up the MIP calculation *** ensure the system stability under the derived UC solution,a parallelized graph power flow(PGPF)algorithm is proposed for the hydro-thermal power system network security ***,case studies of the IEEE 118-bus system and a practical 2749-bus hydro-thermal power system are introduced to demonstrate the feasibility and validity of the proposed graph computing-based MIP framework.

关键词： Graph computing hydro-thermal system mixed integer programming network security unit commitment

Parametic Model for Optimization of Battery Capacity and Power Transmitters of On-line Electric Vehicles in Closed/Open Environments

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CSEE Journal of Power and Energy Systems 2023年第1期9卷 185-196页

作者： Fatima Nisar Syed Haider Imtiaz Alam Asad Waqar Toqeer Ahmed Mudassar Usman Department of Electrical Engineering School of Engineering&Applied Sciences(BSEAS)Bahria UniversityIslamabadPakistan Department of Centre for Advanced Electronics and Photovoltaic Engineering(CAEPE) International Islamic Universityand School of Interdisciplinary Engineering and Science(SINES)National University of Science and Technology(NUST)IslamabadPakistan

An on-line electric vehicle(OLEV)uses a wireless charging phenomenon,in which power transmitters are installed beneath the road and the OLEV’s battery is charged *** paper deals with the optimization of two key economic and design parameters,i.e.,the size of the battery and the power transmitters allocation.A complete model configuration of the OLEV system,including the vehicle design and power transmitter,is implemented using MATLAB/*** battery’s state of charge(SOC)rises and drops according to the vehicle’s velocity and power collection and *** mixed integer programming(MIP)model is used for cost ***,with the help of the SOC graph and MIP model,the battery size and the number of power transmitters,along with their placements,are *** proposed model is applicable to both closed and open environments as it accepts both regulated and deregulated *** test cases are performed for this *** first test case deals with regulated velocity for which we have applied the KAIST campus OLEV’s velocity along with its 13 kWh battery size and 4 power transmitters,and then applied the suggested solution with the same velocity and route i.e.,8 power transmitters with shorter lengths and reduced battery size(3.25 kWh;one-fourth of the first case).SOC is found within limits at the end of the route,saving$1600 and validating the proposed model in this *** the second test case,we use deregulated velocity and optimize both parameters,using the same approach.

关键词： Closed and open environments mixed integer programming on-line electrical vehicle power transmitters state of charge wireless charging

Optimal Dispatch for Battery Energy Storage Station in Distribution Network Considering Voltage Distribution Improvement and Peak Load Shifting

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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 131-139页

作者： Xiangjun Li Rui Ma Wei Gan Shijie Yan State Key Laboratory of Control and Operation of Renewable Energy and Storage Systems China Electric Power Research InstituteBeijingChina College of Information and Engineering Northeastern UniversityShenyangChina

Distribution networks are commonly used to demonstrate low-voltage problems.A new method to improve voltage quality is using battery energy storage stations(BESSs),which has a four-quadrant regulating *** this paper,an optimal dispatching model of a distributed BESS considering peak load shifting is proposed to improve the voltage distribution in a distribution *** objective function is to minimize the power exchange cost between the distribution network and the transmission network and the penalty cost of the voltage *** the process,various constraints are considered,including the node power balance,single/two-way power flow,peak load shifting,line capacity,voltage deviation,photovoltaic station operation,main transformer capacity,and power factor of the distribution *** big M method is used to linearize the nonlinear variables in the objective function and constraints,and the model is transformed into a mixed-integer linear programming problem,which significantly improves the model *** are performed using the modified IEEE 33-node system.A typical time period is selected to analyze the node voltage variation,and the results show that the maximum voltage deviation can be reduced from 14.06%to 4.54%.The maximum peak-valley difference of the system can be reduced from 8.83 to 4.23 MW,and the voltage qualification rate can be significantly ***,the validity of the proposed model is verified through simulations.

关键词： Energy storage station distribution network voltage regulation peak load shifting mixed integer programming