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Topology Optimization for Steady-State Navier-Stokes Flow Based on Parameterized Level Set Based Method 被引量:1
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作者 Peng Wei Zirun Jiang +3 位作者 Weipeng Xu Zhenyu Liu Yongbo Deng Minqiang Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期593-619,共27页
In this paper,we consider solving the topology optimization for steady-state incompressibleNavier-Stokes problems via a new topology optimization method called parameterized level set method,which can maintain a relat... In this paper,we consider solving the topology optimization for steady-state incompressibleNavier-Stokes problems via a new topology optimization method called parameterized level set method,which can maintain a relatively smooth level set function with a local optimality condition.The objective of topology optimization is to􀀀nd an optimal con􀀀guration of theuid and solid materials that minimizes power dissipation under a prescribeduid volume fraction constraint.An arti􀀀cial friction force is added to the Navier-Stokes equations to apply the no-slip boundary condition.Although a great deal of work has been carried out for topology optimization ofuidow in recent years,there are few researches on the topology optimization ofuidow with physical body forces.To simulate theuidow in reality,the constant body force(e.g.,gravity)is considered in this paper.Several 2D numerical examples are presented to discuss the relationships between the proposed method with Reynolds number and initial design,and demonstrate the feasibility and superiority of the proposed method in dealing with unstructuredmesh problems.Three 3D numerical examples demonstrate the proposedmethod is feasible in three-dimensional. 展开更多
关键词 Topology optimization parameterized level set method power dissipation no-slip boundary condition Navier-Stokes equations gravity
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PARAMETERIZED-PROTOTYPE-BASED DYNAMIC OPTIMIZATION DESIGN FOR CAM PROFILE 被引量:1
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作者 彭禹 郝志勇 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第4期310-316,共7页
Aiming at the problems in current cam profile optimization processes, such as simple dynamics models, limited geometric accuracy and low design automatization level, a new dynamic optimization mode is put forward. Bas... Aiming at the problems in current cam profile optimization processes, such as simple dynamics models, limited geometric accuracy and low design automatization level, a new dynamic optimization mode is put forward. Based on the parameterization modeling technique of MSC. ADAMS platform, the different steps in current mode are reorganized, thus obtaining an upgraded mode called the "parameterized-prototype-based cam profile dynamic optimization mode". A parameterized prototype(PP) of valve mechanism is constructed in the course of dynamic optimization for cam profiles. Practically, by utilizing PP and considering the flexibility of the parts in valve mechanism, geometric accuracy and design automatization are improved. 展开更多
关键词 valve mechanism cam profile optimization design parameterized prototype dynamic optimization
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Parameterized Littlewood-Paley Operators and Their Commutators on Lebesgue Spaces with Variable Exponent 被引量:6
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作者 Lijuan Wang Shuangping Tao 《Analysis in Theory and Applications》 CSCD 2015年第1期13-24,共12页
In this paper, by applying the technique of the sharp maximal function and the equivalent representation of the norm in the Lebesgue spaces with variable exponent, the boundedness of the parameterized Litflewood-Paley... In this paper, by applying the technique of the sharp maximal function and the equivalent representation of the norm in the Lebesgue spaces with variable exponent, the boundedness of the parameterized Litflewood-Paley operators, including the parameterized Lusin area integrals and the parameterized Littlewood-Paley gλ^*- functions, is established on the Lebesgue spaces with variable exponent. Furthermore, the boundedness of their commutators generated respectively by BMO functions and Lipschitz functions are also obtained. 展开更多
关键词 parameterized Littlewood-Paley operators COMMUTATORS Lebesgue spaces with variable exponent.
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LOOK-AHEAD ALGORITHM FOR VELOCITY CONTROL BASED ON PARAMETERIZED CURVE INTERPOLATOR 被引量:2
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作者 REN Kun FU Jianzhong CHEN Zichen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第2期23-26,共4页
To avoid suffering gouge and transient overshooting in high speed cutting machining, a novel parametefized curve interpolator model with velocity look-ahead algorithm is proposed. Based on a prearrangement step interp... To avoid suffering gouge and transient overshooting in high speed cutting machining, a novel parametefized curve interpolator model with velocity look-ahead algorithm is proposed. Based on a prearrangement step interpolation algorithm for parameterized curves and considering high curvature points, parameterized curve tool path is divided into acceleration segments and deceleration segments by look-ahead algorithm. Under condition of characteristics of acceleration and deceleration stored in control system, deceleration before high curvature points and acceleration after high curvature points are realized in real-time in high speed cutting machining. Based on new parameterized curve interpolator model with velocity look-ahead algorithm, a real cubic spline is machined simulativly. The simulation results show that velocity look-ahead algorithm improves velocity changing more smoothly. 展开更多
关键词 High speed cutting machining parameterized curve interpolator Look-ahead algorithm
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Non-perturbative Aspects of QCD and Parameterized Quark Propagator 被引量:2
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作者 ZHOU Li-Juan GU Yun-Ting +2 位作者 MA Wei-Xing MENG Cheng-Ju PAN Ji-Huan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期181-188,共8页
Based on the Global Color Symmetry Model, the non-perturbative Q, CD vacuum is investigated in the parameterized fully dressed quark propagator. Our theoretical predictions for various quantities characterized the QCD... Based on the Global Color Symmetry Model, the non-perturbative Q, CD vacuum is investigated in the parameterized fully dressed quark propagator. Our theoretical predictions for various quantities characterized the QCD vacuum are in agreement with those predicted by many other phenomenologieal QCD inspired models. The successful predictions clearly indicate the extensive validity of our parameterized quark propagator used here. A detailed discussion on the arbitrariness in determining the integration cut-off parameter ofμ in calculating QCD vacuum condensates and a good method, which avoided the dependence of calculating results on the cut-off parameter is also strongly recommended to readers. 展开更多
关键词 global color symmetry model parameterized quark propagator non-perturbative QCD vacuumand vacuum condensate
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Hypersingular parameterized Marcinkiewicz integrals with variable kernels on Sobolev and Hardy-Sobolev spaces 被引量:2
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作者 CHEN Jie-cheng YU Xiao ZHANG Yan-dan WANG Hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期420-430,共11页
Let α≥ 0 and 0 〈 ρ ≤ n/2, the boundedness of hypersingular parameterized Marcinkiewicz integrals μΩ,α^ρ with variable kernels on Sobolev spaces Lα^ρ and HardySobolev spaces Hα^ρ is established.
关键词 parameterized Marcinkiewicz integral variable kernel Hardy-Sobolev space L^α-Dini condition
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Parameterized Designing of Gears' Three-dimensional Model Based on Pro/E 被引量:1
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作者 WANG Zhihui CHEN Jing SUN Yaomin School of Electromechanics Engineering,Wuhan University of Technolngy,Wuhan 430070,China, 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期903-907,共5页
This paper took Pro/ENGINEER wildfire2.0 as the development environment and realized the involute helical gears’three-dimensional model parameterized designing which made use of the parameter and relation function of... This paper took Pro/ENGINEER wildfire2.0 as the development environment and realized the involute helical gears’three-dimensional model parameterized designing which made use of the parameter and relation function of Pro/E.This paper also provided a method of editing the equation of the tooth curve,and it can ensure the high precision of the involute helical gear model.It developed the man-machine interactive parameterized designing interface making use of the secondary development function offered by Pro/TOOLKIT.The users can revise the involute helical gear easily by this man-machine interactive.It de- tailedly introduced the method of designing the man-machine interactive interface Using Pro/TOOLKIT and Visual C++.When the users input correlation parameters according to the prompt of the man-machine interactive interface,the three-dimensional model of the involute helical gear is auto-generated.This method simplified the product design process,shortened the period of de- veloping and improved the design efficiency of the gear greatly. 展开更多
关键词 PRO/E HELICAL GEARS parameterized PRO/TOOLKIT
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Parameterized design of nonlinear feedback controllers for servo positioning systems 被引量:1
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作者 Cheng Guoyang Jin Wenguang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期593-599,共7页
To achieve fast, smooth and accurate set point tracking in servo positioning systems, a parameterized design of nonlinear feedback controllers is presented, based on a so-called composite nonlinear feedback (CNF) co... To achieve fast, smooth and accurate set point tracking in servo positioning systems, a parameterized design of nonlinear feedback controllers is presented, based on a so-called composite nonlinear feedback (CNF) control technique. The controller designed here consists of a linear feedback part and a nonlinear part. The linear part is responsible for stability and fast response of the closed-loop system. The nonlinear part serves to increase the damping ratio of closed-loop poles as the controlled output approaches the target reference. The CNF control brings together the good points of both the small and the large damping ratio cases, by continuously scheduling the damping ratio of the dominant closed-loop poles and thus has the capability for superior transient performance, i.e. a fast output response with low overshoot. In the presence of constant disturbances, an integral action is included so as to remove the static bias. An explicitly parameterized controller is derived for servo positioning systems characterized by second-order model. Practical application in a micro hard disk drive servo system is then presented, together with some discussion of the rationale and characteristics of such design. Simulation and experimental results demonstrate the effectiveness of this control design methodology. 展开更多
关键词 control systems nonlinear feedback parameterized design servo tracking disturbance.
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Parameterized time-frequency analysis to separate multi-radar signals 被引量:1
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作者 Wenlong Lu Junwei Xie +1 位作者 Heming Wang Chuan Sheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期493-502,共10页
Multi-radar signal separation is a critical process in modern reconnaissance systems. However, the complicated battlefield is typically confronted with increasing electronic equipment and complex radar waveforms. The ... Multi-radar signal separation is a critical process in modern reconnaissance systems. However, the complicated battlefield is typically confronted with increasing electronic equipment and complex radar waveforms. The intercepted signal is difficult to separate with conventional parameters because of severe overlapping in both time and frequency domains. On the contrary, time-frequency analysis maps the 1D signal into a 2D time-frequency plane, which provides a better insight into the signal than traditional methods. Particularly, the parameterized time-frequency analysis (PTFA) shows great potential in processing such non stationary signals. Five procedures for the PTFA are proposed to separate the overlapped multi-radar signal, including initiation, instantaneous frequency estimation with PTFA, signal demodulation, signal separation with adaptive filter and signal recovery. The proposed method is verified with both simulated and real signals, which shows good performance in the application on multi-radar signal separation. 展开更多
关键词 intercepted multi-radar signal parameterized time-frequency analysis DEMODULATION adaptive filtering
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Weighted Parameterized Correlation Coefficients of Indeterminacy Fuzzy Multisets and Their Multicriteria Group Decision Making Method with Different Decision Risks 被引量:1
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作者 Cheng Du Jun Ye 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第10期341-354,共14页
Real-life data introduce noise,uncertainty,and imprecision to statistical projects;it is advantageous to consider strategies to overcome these information expressions and processing problems.Neutrosophic(indeterminate... Real-life data introduce noise,uncertainty,and imprecision to statistical projects;it is advantageous to consider strategies to overcome these information expressions and processing problems.Neutrosophic(indeterminate)numbers can flexibly and conveniently represent the hybrid information of the partial determinacy and partial indeterminacy in an indeterminate setting,while a fuzzy multiset is a vital mathematical tool in the expression and processing of multi-valued fuzzy information with different and/or same fuzzy values.If neutrosophic numbers are introduced into fuzzy sequences in a fuzzy multiset,the introduced neutrosophic number sequences can be constructed as the neutrosophic number multiset or indeterminate fuzzy multiset.Motivated based on the idea,this study first proposes an indeterminate fuzzy multiset,where each element in a universe set can be repeated more than once with the different and/or identical indeterminate membership values.Then,we propose the parameterized correlation coefficients of indeterminate fuzzy multisets based on the de-neutrosophication of transforming indeterminate fuzzy multisets into the parameterized fuzzy multisets by a parameter(the parameterized de-neutrosophication method).Since indeterminate decision-making issues need to be handled by an indeterminate decision-making method,a group decision-making method using the weighted parameterized correlation coefficients of indeterminate fuzzy multisets is developed along with decision makers’different decision risks(small,moderate,and large risks)so as to handle multicriteria group decision-making problems in indeterminate fuzzy multiset setting.Finally,the developed group decision-making approach is used in an example on a selection problem of slope design schemes for an open-pit mine to demonstrate its usability and flexibility in the indeterminate group decision-making problem with indeterminate fuzzy multisets. 展开更多
关键词 Indeterminate fuzzy multiset parameterized correlation coefficient multicriteria group decision making neutrosophic number slope design scheme
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Parameterized thermal model of a mixed mantle convection 被引量:1
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作者 张健 石耀霖 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第6期699-709,728,共12页
Simple parameterized models, either whole mantle convection or layered mantleconvection, cannot explain the tectonic characteristics of the Earth's evolution history, therefore a mixed mantle convection model has ... Simple parameterized models, either whole mantle convection or layered mantleconvection, cannot explain the tectonic characteristics of the Earth's evolution history, therefore a mixed mantle convection model has been carried out in this paper. We introduce a time-dependent parameter F, which denotes the ratio betWeen the mantle material involved in whole mantle convection and the material of the entire mantle, and introduce a local Rayleigh number Raloc as well as two critical numbers Ra1 and Ra2. These parameters are used to describe the stability of the phase boundary between the upper and lower mantle. The result shows that the mixed mantle convection model is able to simulate the episodic tectonic evolution of the Earth. 展开更多
关键词 thermal history of the Earth parameterized model mixed mantle convection
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A Comparative Study of the Numerical Simulation of the 1998 Summer Flood in China by Two Kinds of Cumulus Convective Parameterized Methods
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作者 平凡 高守亭 王会军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第1期149-158,共10页
The NCC T63L20 model of the National Climate Center, China Meteorological Administration is employed to simulate the 1998 summer flood, which mainly occurred in the region of the Yangtze River and Northeast China. For... The NCC T63L20 model of the National Climate Center, China Meteorological Administration is employed to simulate the 1998 summer flood, which mainly occurred in the region of the Yangtze River and Northeast China. For this study, two kinds of cumulus convection parameterized schemes are employed in this model respectively. The simulations show that the Gregory parameterized scheme, which is still used in the United Kingdom Meteorological Office routine model, simulates more reasonable rainfall amount and distribution compared to the Kuo-type scheme. Moreover, the Gregory scheme better simulates the tendency of general circulation than the Kuo-type scheme. On the whole, the Gregory scheme provides a good simulation of the main features of the seasonal precipitation and general circulation in China, although the simulated result still exhibits some departures from the observations. 展开更多
关键词 cumulus convection numerical simulation parameterized scheme the heavy flood
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Parameterized Littlewood-Paley Operators on Weighted Herz Spaces
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作者 Yueshan Wang Aiqing Chen 《Analysis in Theory and Applications》 CSCD 2017年第4期301-315,共15页
The strong type and weak type estimates of parameterized Littlewood-Paley operators on the weighted Herz spaces Kq α,p(ω1,ω2) are considered. The boundednessof the commutators generated by BMO functions and param... The strong type and weak type estimates of parameterized Littlewood-Paley operators on the weighted Herz spaces Kq α,p(ω1,ω2) are considered. The boundednessof the commutators generated by BMO functions and parameterized Littlewood-Paley operators are also obtained. 展开更多
关键词 parameterized Littlewood-Paley operator Herz space weak Herz space BMO com-mutator Muckenhoupt weight.
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A note on parameterized Marcinkiewicz integrals with variable kernels
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作者 WANG Hui ZHANG Chun-jie 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第3期315-320,共6页
In this paper,the parameterized Marcinkiewicz integrals with variable kernels defined by μΩ^ρ(f)(x)=(∫0^∞│∫│1-y│≤t Ω(x,x-y)/│x-y│^n-p f(y)dy│^2dt/t1+2p)^1/2 are investigated.It is proved that ... In this paper,the parameterized Marcinkiewicz integrals with variable kernels defined by μΩ^ρ(f)(x)=(∫0^∞│∫│1-y│≤t Ω(x,x-y)/│x-y│^n-p f(y)dy│^2dt/t1+2p)^1/2 are investigated.It is proved that if Ω∈ L∞(R^n) × L^r(S^n-1)(r〉(n-n1p'/n) is an odd function in the second variable y,then the operator μΩ^ρ is bounded from L^p(R^n) to L^p(R^n) for 1 〈 p ≤ max{(n+1)/2,2}.It is also proved that,if Ω satisfies the L^1-Dini condition,then μΩ^ρ is of type(p,p) for 1 〈 p ≤ 2,of the weak type(1,1) and bounded from H1 to L1. 展开更多
关键词 parameterized Marcinkiewicz integral variable kernel rotation method
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Parameterized Solution to a Class of Sylvester Matrix Equations
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作者 Yu-Peng Qiao Hong-Sheng Qi Dai-Zhan Cheng 《International Journal of Automation and computing》 EI 2010年第4期479-483,共5页
A class of formulas for converting linear matrix mappings into conventional linear mappings are presented. Using them, an easily computable numerical method for complete parameterized solutions of the Sylvester matrix... A class of formulas for converting linear matrix mappings into conventional linear mappings are presented. Using them, an easily computable numerical method for complete parameterized solutions of the Sylvester matrix equation AX - EXF = BY and its dual equation XA - FXE = YC are provided. It is also shown that the results obtained can be used easily for observer design. The method proposed in this paper is universally applicable to linear matrix equations. 展开更多
关键词 Sylvester matrix equation parameterized solution Kronecker product linear matrix equation Luenberger observers
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Numerical simulation of HP rotor cooling configuration using parameterized method
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作者 周鸿儒 顾忠华 +1 位作者 韩万金 刘占生 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第2期134-138,共5页
This paper implemented cooling configuration design on certain gas turbine HP rotor using parameterized method.It is convenient for complicated gas turbine blade modeling using parameters and also benefit for the geom... This paper implemented cooling configuration design on certain gas turbine HP rotor using parameterized method.It is convenient for complicated gas turbine blade modeling using parameters and also benefit for the geometry modify in later period.Parameterized modeling is the foundation of air cooling turbine blade design method engineering application.Mesh quality can be awarded when generated complicated cooling configuration blade grids,and also the increase of calculation error can arise by many mesh blocks.Film cooling and serpentine passage can effectively enhance the cooling effectiveness and protect blade. 展开更多
关键词 conjugate heat transfer air cooling turbine parameterized method ROTOR
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Asymptotic Estimates for Second-Order Parameterized Singularly Perturbed Problem
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作者 Mustafa Kudu 《Applied Mathematics》 2014年第13期1988-1992,共5页
The boundary value problem (BVP) for parameterized singularly perturbed second order nonlinear ordinary differential equation is considered. The boundary layer behavior of the solution and its first and second derivat... The boundary value problem (BVP) for parameterized singularly perturbed second order nonlinear ordinary differential equation is considered. The boundary layer behavior of the solution and its first and second derivatives have been established. An example supporting the theoretical analysis is presented. 展开更多
关键词 parameterized Problem ASYMPTOTIC BOUNDS SINGULAR PERTURBATION BOUNDARY Layer
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The Maximum Hamilton Path Problem with Parameterized Triangle Inequality
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作者 Weidong Li Jianping Li +1 位作者 Zefeng Qiao Honglin Ding 《Communications and Network》 2013年第1期96-100,共5页
Given a complete graph with edge-weights satisfying parameterized triangle inequality, we consider the maximum Hamilton path problem and design some approximation algorithms.
关键词 MAXIMUM TRAVELING SALESMAN PROBLEM parameterized TRIANGLE INEQUALITY Approximation Algorithm
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Experimental Evaluation of Parameterized Nonlinear MPC Applied to PEM Fuel Cell
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作者 Cédric Damour Dominique Grondin +2 位作者 Michel Benne Brigitte Grondin-Perez Jean-Pierre Chabriat 《Engineering(科研)》 2020年第2期99-116,共18页
This paper proposes a parameterized nonlinear model-based predictive control (NMPC) strategy to tackle the oxygen excess ratio regulation challenge of a proton exchange membrane fuel cell. In practice, the most challe... This paper proposes a parameterized nonlinear model-based predictive control (NMPC) strategy to tackle the oxygen excess ratio regulation challenge of a proton exchange membrane fuel cell. In practice, the most challenging part regarding NMPC strategies remains the on-line implementation. In fact, NMPC strategies, at least in their basic form, involve heavy computation to solve the optimization problem. In this work, a specific parameterization of control actions has been designed to address this limitation and achieve on-line implementation. To assess the effectiveness and relevance of the proposed strategy, the controller has been implemented on-line, experimentally validated on a real fuel cell and compared to the built-in controller. Performance of the parameterized NMPC controller in terms of setpoint tracking accuracy, disturbances rejection and computational cost, have tested under several control scenarios. Experimental results have shown the excellent tracking capability, disturbances rejection ability and low computational cost of the NMPC controller, regardless of the operating conditions. Moreover, compared to the built-in controller the proposed strategy has demonstrated better disturbances rejection capability. Overall, the proposed parameterized NMPC controller appears as an excellent candidate to address the oxygen excess ratio regulation issue. 展开更多
关键词 CONTROL Application parameterized NONLINEAR Model PREDICTIVE CONTROL PROTON EXCHANGE Membrane Fuel Cell
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Carbody Structural Lightweighting Based on Implicit Parameterized Model 被引量:7
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作者 CHEN Xin MA Fangwu +1 位作者 WANG Dengfeng XIE Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第3期483-487,共5页
Most of recent research on carbody lightweighting has focused on substitute material and new processing technologies rather than structures. However, new materials and processing techniques inevitably lead to higher c... Most of recent research on carbody lightweighting has focused on substitute material and new processing technologies rather than structures. However, new materials and processing techniques inevitably lead to higher costs. Also, material substitution and processing lightweighting have to be realized through body structural profiles and locations. In the huge conventional workload of lightweight optimization, model modifications involve heavy manual work, and it always leads to a large number of iteration calculations. As a new technique in carbody lightweighting, the implicit parameterization is used to optimize the carbody structure to improve the materials utilization rate in this paper. The implicit parameterized structural modeling enables the use of automatic modification and rapid multidisciplinary design optimization (MDO) in carbody structure, which is impossible in the traditional structure finite element method (FEM) without parameterization. The structural SFE parameterized model is built in accordance with the car structural FE model in concept development stage, and it is validated by some structural performance data. The validated SFE structural parameterized model can be used to generate rapidly and automatically FE model and evaluate different design variables group in the integrated MDO loop. The lightweighting result of body-in-white (BIW) after the optimization rounds reveals that the implicit parameterized model makes automatic MDO feasible and can significantly improve the computational efficiency of carbody structural lightweighting. This paper proposes the integrated method of implicit parameterized model and MDO, which has the obvious practical advantage and industrial significance in the carbody structural lightweighting design. 展开更多
关键词 carbody structural lightweighting implicit parameterization MDO BIW
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