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An Optimal DASH Diet Model for People with Hypertension Using Linear Programming Approach 被引量:1
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作者 Anayo Charles Iwuji Mercy Nnanna Nonso Ifeyinwa C. Ndulue 《Open Journal of Optimization》 2016年第1期14-21,共8页
Selecting diets by quantitative techniques is becoming increasingly common. Linear programming is the most popular technique for the selection of least cost mixes of food to meet specific nutritional requirements for ... Selecting diets by quantitative techniques is becoming increasingly common. Linear programming is the most popular technique for the selection of least cost mixes of food to meet specific nutritional requirements for a particular group of persons for either general health or disease-related reason. Hypertension is a silent killer and its prevalence rate especially in the developing countries, which has been mostly associated to demographic, environmental and genetic factors, is becoming alarming. The DASH diet has been clinically proven to prevent and control hypertension. In this paper, a model that provides a Daily Optimal (minimum cost) DASH Diet plan for people with hypertension is formulated. The objective is to obtain daily minimum cost diet plans that satisfy the DASH Diets’ nutrients Tolerable Upper and Lower Intake for different daily Calorie Levels. The formulated DASH diet model was further illustrated using real data set with food samples gotten from the DASH eating plan chart. A DASH diet model for a hypertensive person with a 2000-daily-caloric need was formulated and its optimal diet plan for a day obtained with a total cost of 944.41 Naira. Optimal diet plans for other recommended daily calorie levels were also obtained. 展开更多
关键词 DASH (Dietary approaches to Stop Hypertension) HYPERTENSION Minimum Cost Diet Plan linear Programming Diet Problem
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Two-Phase Multi Objective Fuzzy Linear Programming Approach for Sustainable Irrigation Planning
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作者 D. G. Regulwar Jyotiba B. Gurav 《Journal of Water Resource and Protection》 2013年第6期642-651,共10页
The objective of the present study is to develop the irrigation planning model and to apply the same in the form of Two-Phase Multi Objective Fuzzy Linear Programming (TPMOFLP) approach for crop planning in command ar... The objective of the present study is to develop the irrigation planning model and to apply the same in the form of Two-Phase Multi Objective Fuzzy Linear Programming (TPMOFLP) approach for crop planning in command area of Jayakwadi Project Stage I, Maharashtra State, India. The development of TPMOFLP model is on the basis of various Linear Programming (LP) models and Multi Objective Fuzzy Linear Programming (MOFLP) models, these models have been applied for maximization of the Net Benefits (NB), Crop production (CP), Employment Generation (EG) and Manure Utilization (MU) respectively. The significant increase in the value of level of satisfaction (λ) has been found from 0.58 to 0.65 by using the TPMOFLP approach as compare to that of MOFLP model based on maxmin approach. The two-phase approach solution provides NB = 1503.56 Million Rupees, CP = 335729.30 Tons, EG = 29.74 Million Man days and MU = 160233.70 Tons respectively. The proposed model will be helpful for the Decision Maker (DM) to take a decision under conflicting situation while planning for different conflicting objectives simultaneously and has potential to find out an integrated irrigation planning with prime consideration for economic, social and environmental issue. 展开更多
关键词 SUSTAINABLE IRRIGATION PLANNING Multi Objective Fuzzy linear PROGRAMMING Maxmin approach TWO-PHASE approach
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Observer design for matrix second order linear systems with uncertain disturbance input-a parametric approach
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作者 Wu Yunli Li Zhibin Duan Cruangren 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期811-816,823,共7页
A simple parametric approach to design a full-order observer for matrix second-order linear systems with uncertain disturbance input in the matrixsecond-order framework is proposed. The basic idea is to minimize the H... A simple parametric approach to design a full-order observer for matrix second-order linear systems with uncertain disturbance input in the matrixsecond-order framework is proposed. The basic idea is to minimize the H2 norm of the transfer function from disturbance to estimation error using the design degrees of freedom provided by a parametric approach in the observer design. Besides the design parameters, the eigenvalues of the closed-loop system are also optimized within desired regions on the left-half of the complex plane. Using the proposed approach, additional specifications can be easily achieved. A spring-mass system is using to show the effect of the proposed approaches. 展开更多
关键词 linear systems uncertain disturbance input observers parametric approach optimization.
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A mixed integer linear programming approach for municipal solid waste management
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《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第4期49-63,共15页
AmixedintegerlinearprogrammingapproachformunicipalsolidwastemanagementGordonGuoHeHuangEnvironmentalSystemsEn... AmixedintegerlinearprogrammingapproachformunicipalsolidwastemanagementGordonGuoHeHuangEnvironmentalSystemsEngineering,Univer... 展开更多
关键词 A mixed integer linear programming approach for municipal solid waste management
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Probabilistic Robust Linear Parameter-varying Control of a Small Helicopter Using Iterative Scenario Approach
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作者 Zhou Fang Hua Tian Ping Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2015年第1期85-93,共9页
In this paper, we present an iterative scenario approach (ISA) to design robust controllers for complex linear parameter-varying (LPV) systems with uncertainties. The robust controller synthesis problem is transformed... In this paper, we present an iterative scenario approach (ISA) to design robust controllers for complex linear parameter-varying (LPV) systems with uncertainties. The robust controller synthesis problem is transformed to a scenario design problem, with the scenarios generated by identically extracting random samples on both uncertainty parameters and scheduling parameters. An iterative scheme based on the maximum volume ellipsoid cutting-plane method is used to solve the problem. Heuristic logic based on relevance ratio ranking is used to prune the redundant constraints, and thus, to improve the numerical stability of the algorithm. And further, a batching technique is presented to remarkably enhance the computational efficiency. The proposed method is applied to design an output-feedback controller for a small helicopter. Multiple uncertain physical parameters are considered, and simulation studies show that the closed-loop performance is quite good in both aspects of model tracking and dynamic decoupling. For robust LPV control problems, the proposed method is more computationally efficient than the popular stochastic ellipsoid methods. © 2014 Chinese Association of Automation. 展开更多
关键词 Aircraft control Algorithms Computation theory Computational efficiency Controllers Design Helicopters Optimization Problem solving Robust control Scheduling Stochastic systems Uncertainty analysis
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REFINED HYBRID MINDLIN PLATE ELEMENT FOR GEOMETRICALLY NON LINEAR ANALYSIS
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作者 郑世杰 陶宝祺 陈万吉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期90-94,共5页
Based upon a generalized variational principle, which relaxed the inter element continuity requirements, a novel refined hybrid Mindlin plate element is developed, its non linear element stiffness matrices are decom... Based upon a generalized variational principle, which relaxed the inter element continuity requirements, a novel refined hybrid Mindlin plate element is developed, its non linear element stiffness matrices are decomposed into a series of matrices with respect to the assumed strain modes. The formulation presented in this paper is different from any other non linear mixed/hybrid element formulation all successful experience of linear hybrid formulation is absorbed into the formulation(adding non conforming modes and realizing orthogonalization) Numerical results show that the present approach is more effective than any other non linear hybrid element formulation over the accuracy and computational efficiency. In addition, non conforming modes can also overcome the shear locking effect. 展开更多
关键词 non linear mechanics non conforming mode orthogonal approach geometrically non linear refined element
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Non-fragile Observer Design for Fractional-order One-sided Lipschitz Nonlinear Systems 被引量:1
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作者 Yong-Hong Lan Wen-Jie Li +1 位作者 Yan Zhou Yi-Ping Luo 《International Journal of Automation and computing》 EI CSCD 2013年第4期296-302,共7页
This paper is concerned with the problem of the full-order observer design for a class of fractional-order Lipschitz nonlinear systems. By introducing a continuous frequency distributed equivalent model and using an i... This paper is concerned with the problem of the full-order observer design for a class of fractional-order Lipschitz nonlinear systems. By introducing a continuous frequency distributed equivalent model and using an indirect Lyapunov approach, the sufficient condition for asymptotic stability of the full-order observer error dynamic system is presented. The stability condition is obtained in terms of LMI, which is less conservative than the existing one. A numerical example demonstrates the validity of this approach. 展开更多
关键词 FRACTIONAL-ORDER nonlinear system observer design indirect Lyapunov approach linear matrix inequality (LMI).
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Direct thrust control for multivariable turbofan approach 被引量:5
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作者 Yiyang ZHU Jinquan HUANG +1 位作者 Muxuan PAN Wenxiang ZHOU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第6期125-136,共12页
A novel turbofan Direct Thrust Control(DTC)architecture based on Linear ParameterVarying(LPV)approach for a two-spool turbofan engine thrust control is proposed in this paper.Instead of transforming thrust command to ... A novel turbofan Direct Thrust Control(DTC)architecture based on Linear ParameterVarying(LPV)approach for a two-spool turbofan engine thrust control is proposed in this paper.Instead of transforming thrust command to shaft speed command and pressure ratio command,the thrust will be directly controlled by an optimal controller with two control variables.LPV model of the engine is established for the designing of thrust estimator and controller.A robust LPV H∞filter is introduced to estimate the unmeasurable thrust according to measurable engine states.The thrust estimation error system is proved to be Affinely Quadratically Stable(AQS)in the whole parameter box with a prescribed H∞performance indexγ.Due to the existence of overdetermined equations,the solving of controller parameters is a multi-solution problem.Therefore,Particle Swarm Optimization(PSO)algorithm is used to optimize the controller parameters to obtain satisfactory control performance based on the engine’s LPV model.Numerical simulations show that the thrust estimator can acquire smooth and accurate estimating results when sensor noise exists.The optimal controller can receive desired control performance both in steady and transition control tasks within the engine working states above the idle,verifying the effectiveness of the proposed DTC architecture’s application in thrust direct control problem. 展开更多
关键词 Turbofan engine Direct thrust control linear Parameter Varying(LPV)approach Particle Swarm Optimization(PSO) Robust LPV H∞filter
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Dverview and Main Advances in Permutation Tests for Linear Regression Models 被引量:1
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作者 Massimiliano Giacalone Angela Alibrandi 《Journal of Mathematics and System Science》 2015年第2期53-59,共7页
When the population, from which the samples are extracted, is not normally distributed, or if the sample size is particularly reduced, become preferable the use of not parametric statistic test. An alternative to the ... When the population, from which the samples are extracted, is not normally distributed, or if the sample size is particularly reduced, become preferable the use of not parametric statistic test. An alternative to the normal model is the permutation or randomization model. The permutation model is nonparametric because no formal assumptions are made about the population parameters of the reference distribution, i.e., the distribution to which an obtained result is compared to determine its probability when the null hypothesis is true. Typically the reference distribution is a sampling distribution for parametric tests and a permutation distribution for many nonparametric tests. Within the regression models, it is possible to use the permutation tests, considering their ownerships of optimality, especially in the multivariate context and the normal distribution of the response variables is not guaranteed. In the literature there are numerous permutation tests applicable to the estimation of the regression models. The purpose of this study is to examine different kinds of permutation tests applied to linear models, focused our attention on the specific test statistic on which they are based. In this paper we focused our attention on permutation test of the independent variables, proposed by Oja, and other methods to effect the inference in non parametric way, in a regression model. Moreover, we show the recent advances in this context and try to compare them. 展开更多
关键词 Permutation Tests linear Regression Models Non Parametric approach.
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Non-Traveling Wave Solutions for the (1 + 1)-Dimensional Burgers System by Riccati Equation Mapping Approach
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作者 Ruiyang Xu Songhua Ma 《Applied Mathematics》 2013年第10期123-125,共3页
Starting from the symbolic computation system Maple and Riccati equation mapping approach and a linear variable separation approach, a new family of non-traveling wave solutions of the (1 + 1)-dimensional Burgers syst... Starting from the symbolic computation system Maple and Riccati equation mapping approach and a linear variable separation approach, a new family of non-traveling wave solutions of the (1 + 1)-dimensional Burgers system is derived. 展开更多
关键词 RICCATI Equation MAPPING approach linear Variable Separation approach BURGERS SYSTEM Non-Traveling Wave Solutions
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Optimal Choice of Weighting Factors in Adaptive Linear Quadratic Control
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作者 Jiri Vojtesek Petr Dostal 《International Journal of Automation and computing》 EI CSCD 2014年第3期241-248,共8页
Most of the processes in the industry have nonlinear behavior. Control of such processes with conventional control methods could lead to unstable, suboptimal, etc., results. On the other hand, the adaptive control is ... Most of the processes in the industry have nonlinear behavior. Control of such processes with conventional control methods could lead to unstable, suboptimal, etc., results. On the other hand, the adaptive control is a technique widely used for controlling of nonlinear systems. The approach here is based on the recursive identification of the external linear model as a linear representation of the originally nonlinear system. The controller then reacts to the change of the working point or disturbances which could occur by the change of the parameters, structure, etc. The polynomial synthesis together with the linear quadratic(LQ) approach is employed here for the controller synthesis. These techniques satisfy basic control requirements such as the stability, the reference signal tracking and the disturbance attenuation. Resulted controller could be tuned with the choice of weighting factors in LQ approach. This work investigates the effect of these factors on control results. Proposed methods are tested on the mathematical model of the isothermal continuous stirred-tank reactor and simulated results are also verified on the real model of the continuous stirred tank reactor. 展开更多
关键词 SIMULATION adaptive control recursive identification linear quadratic(LQ) approach continuous stirred-tank reactor(CSTR).
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Sensor Faults Observer Design with H_∞ Performance for Non-linear T-S systems
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作者 Imen Haj Brahim Maha Bouattour +2 位作者 Driss Mehdi Mohamed Chaabane Ghani Hashim 《International Journal of Automation and computing》 EI CSCD 2013年第6期563-570,共8页
This paper deals with the problem of the state estimation and the sensor faults detection for nonlinear perturbed systems described by Takagi-Sugeno (T-S) fuzzy models with unmeasurable premise variables. Indeed, a ... This paper deals with the problem of the state estimation and the sensor faults detection for nonlinear perturbed systems described by Takagi-Sugeno (T-S) fuzzy models with unmeasurable premise variables. Indeed, a T-S observer is synthesized, in descriptor form, to estimate both the system states and the sensor faults simultaneously. The idea of the proposed approach is to introduce the sensor fault as an auxiliary variable in the state vector. Besides, the T-S model with unmeasurable premise variables is reduced to a perturbed model with measurable variables. Convergence conditions are established with Lyapunov theory and the H∞ performance in order to guarantee the best robustness to disturbances. These conditions are expressed in terms of linear matrix inequalities (LMIs). The parameters of the observer are computed using the solution of the LMI conditions. Finally, a numerical example is given to illustrate the design procedures. Simulation results show the satisfactory performances. 展开更多
关键词 Takagi-Sugeno (T-S) fuzzy system sensor faults H∞ performance descriptor approach OBSERVER linear matrix inequality(LMI).
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Spectral Characteristics of the Best Affine Approach of Multi-Output m-Valued Logical Functions
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作者 ZHAO Yaqun YING Dinghai FENG Dengguo 《Wuhan University Journal of Natural Sciences》 CAS 2007年第1期185-188,共4页
This paper discusses the best affine approach (BAA) of multi-output m-valued logical functions. First, it gives the spectra of rate of accordance between multi-output m-valued logical functions and their affine func... This paper discusses the best affine approach (BAA) of multi-output m-valued logical functions. First, it gives the spectra of rate of accordance between multi-output m-valued logical functions and their affine functions, then analyzes the BAA of multi-output m-valued logical functions and finally gives the spectral characteristics of BAA of multi-output m-valued logical functions. 展开更多
关键词 multi-output m-valued logical functions linear spectrum cyclic spectrum BAA(best affine approach
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Analytical solutions to nonlinear conservative oscillator with fifth-order nonlinearity 被引量:4
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作者 M.G.Sfahani S.S.Ganji +2 位作者 A.Barari H.Mirgolbabaei G.Domairry 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第3期367-374,共8页
This paper describes analytical and numerical methods to analyze the steady state periodic response of an oscillator with symmetric elastic and inertia nonlinearity. A new implementation of the homotopy perturbation m... This paper describes analytical and numerical methods to analyze the steady state periodic response of an oscillator with symmetric elastic and inertia nonlinearity. A new implementation of the homotopy perturbation method (HPM) and an ancient Chinese method called the max-rain approach are presented to obtain an approximate solution. The major concern is to assess the accuracy of these approximate methods in predicting the system response within a certain range of system parameters by examining their ability to establish an actual (numerical) solution. Therefore, the analytical results are compared with the numerical results to illustrate the effectiveness and convenience of the proposed methods. 展开更多
关键词 non-linear oscillation homotopy perturbation method (HPM) max-min approach (MMA) Rung-Kutta method (R-KM) large amplitude free vibrations
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A Series Approach to Perturbed Stochastic Volterra Equations of Convolution Type
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作者 Anna Karczewska Bartosz Bandrowski 《Advances in Pure Mathematics》 2015年第11期660-671,共12页
In the paper, perturbed stochastic Volterra Equations with noise terms driven by series of independent scalar Wiener processes are considered. In the study, the resolvent approach to the equations under consideration ... In the paper, perturbed stochastic Volterra Equations with noise terms driven by series of independent scalar Wiener processes are considered. In the study, the resolvent approach to the equations under consideration is used. Sufficient conditions for the existence of strong solution to the class of perturbed stochastic Volterra Equations of convolution type are given. Regularity of stochastic convolution is supplied, as well. 展开更多
关键词 STOCHASTIC linear Volterra EQUATION PERTURBED EQUATION Strong SOLUTION Resolvent Mild SOLUTION STOCHASTIC CONVOLUTION SERIES approach
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Probabilistic Approach to the Asynchronous Iteration
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作者 A. S. Rasulov M. T. Bakoev D. R. Akabirhodjaeva 《Journal of Applied Mathematics and Physics》 2014年第1期32-40,共9页
In this work we will consider asynchronous iteration algorithms. As is well known in multiprocessor computers the parallel application of iterative methods often shows poor scaling and less optimal parallel efficiency... In this work we will consider asynchronous iteration algorithms. As is well known in multiprocessor computers the parallel application of iterative methods often shows poor scaling and less optimal parallel efficiency. The ordinary iterative asynchronous method often has much better parallel efficiency as they almost never need to wait to communicate between possessors. We will study probabilistic approach in asynchronous iteration algorithms and present a mathematical description of this computational process to the multiprocessor environment. The result of our simple numerical experiments shows a convergence and efficiency of asynchronous iterative processes for considered nonlinear problems. 展开更多
关键词 ASYNCHRONOUS ITERATIONS linear and Nonlinear Equations MULTIPROCESSOR COMPUTERS ITERATIVE Method with Memory Probabilistic approach
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Robust fault detection in linear systemsbased on full-order state observers
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作者 Aiguo WU Guangren DUAN 《控制理论与应用(英文版)》 EI 2007年第4期325-330,共6页
A parametric approach to robust fault detection in linear systems with unknown disturbances is presented.The residual is generated using full-order state observers(FSO).Based on an analytical solution to a type of Syl... A parametric approach to robust fault detection in linear systems with unknown disturbances is presented.The residual is generated using full-order state observers(FSO).Based on an analytical solution to a type of Sylvester matrix equations,the parameterization of the observer gain matrix is given.In terms of the design degrees of freedom provided by the parametric observer design and a group of introduced parameter vectors,a sufficient and necessary condition for fullorder state observer design with disturbance decoupling is then established.By properly constraining the design parameters according to this proposed condition,the effect of the disturbance on the residual signal is also decoupled,and a simple algorithm is developed.The presented approach offers all the degrees of design freedom.Finally,a numerical example illustrates the effect of the proposed approach. 展开更多
关键词 Robust fault detection Full-order state observers linear systems Parametric approach
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Optimal Cooperative Secondary Control for Islanded DC Microgrids via a Fully Actuated Approach
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作者 Yi Yu Guo-Ping Liu +1 位作者 Yi Huang Peng Shi 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期405-417,共13页
DC-DC converter-based multi-bus DC microgrids(MGs) in series have received much attention, where the conflict between voltage recovery and current balancing has been a hot topic. The lack of models that accurately por... DC-DC converter-based multi-bus DC microgrids(MGs) in series have received much attention, where the conflict between voltage recovery and current balancing has been a hot topic. The lack of models that accurately portray the electrical characteristics of actual MGs while is controller design-friendly has kept the issue active. To this end, this paper establishes a large-signal model containing the comprehensive dynamical behavior of the DC MGs based on the theory of high-order fully actuated systems, and proposes distributed optimal control based on this. The proposed secondary control method can achieve the two goals of voltage recovery and current sharing for multi-bus DC MGs. Additionally, the simple structure of the proposed approach is similar to one based on droop control, which allows this control technique to be easily implemented in a variety of modern microgrids with different configurations. In contrast to existing studies, the process of controller design in this paper is closely tied to the actual dynamics of the MGs. It is a prominent feature that enables engineers to customize the performance metrics of the system. In addition, the analysis of the stability of the closed-loop DC microgrid system, as well as the optimality and consensus of current sharing are given. Finally, a scaled-down solar and battery-based microgrid prototype with maximum power point tracking controller is developed in the laboratory to experimentally test the efficacy of the proposed control method. 展开更多
关键词 DC microgrids distributed control high-order fully actuated system approach linear quadratic regulator microgrid modeling secondary control
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High Order IMEX Stochastic Galerkin Schemes for Linear Transport Equation with Random Inputs and Diffusive Scalings
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作者 Zheng Chen Lin Mu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期325-339,共15页
In this paper,we consider the high order method for solving the linear transport equations under diffusive scaling and with random inputs.To tackle the randomness in the problem,the stochastic Galerkin method of the g... In this paper,we consider the high order method for solving the linear transport equations under diffusive scaling and with random inputs.To tackle the randomness in the problem,the stochastic Galerkin method of the generalized polynomial chaos approach has been employed.Besides,the high order implicit-explicit scheme under the micro-macro decomposition framework and the discontinuous Galerkin method have been employed.We provide several numerical experiments to validate the accuracy and the stochastic asymptotic-preserving property. 展开更多
关键词 Stochastic Galerkin scheme linear transport equations generalized polynomial approach stochastic asymptotic-preserving property
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