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Internal ballistic simulation of multi-burning-rate solid rocket motor based on parameterized feature CAD modelInternal ballistic simulation of multi-burning-rate solid rocket motor based on parameterized feature CAD model

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航空动力学报 2015年第12期30卷 3017-3028页

作者： CHEN Wei LIANG guo-zhu School of Astronautics Beijing University of Aeronautics and Astronautics

Internal ballistic simulation(IBS)method of multi-burning-rate solid rocket motor(SRM)was developed based on 3-D burning regression method by parameterized feature CAD model(PFCADM)and lumped parameter,in consideration of time-dependent,erosive-burning-effect from internal ballistic numerical *** driving multi-parameter CAD model based on PFCADM,the approach is capable of conducting the geometric regression simulation of various grain combinations of complex configurations with different burning *** suitably simplifying the internal ballistic numerical algorithm,the problems of coupling geometric regression simulation of sub-grains of different burning rates and high computational consumption of internal ballistic calculation were *** tri-burning-rate grain motor,which had been firing-tested,was used as the validation case of *** results show that,with the 3-D grain regression model and sufficient accurate internal ballistic algorithm,the method realizes IBS of the case in low computationalconsumption prediction of its performance within the accuracy of 2% during *** application of the method provides a practical approach to aid SRM design of multi-burning-rate grain.

关键词： solid rocket motor internal ballistic simulatio multi-burning-rate grain design unsteady flow

On the Asymptotic Uniformity of the Quantization Error for Moran Measures on R^1

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Acta Mathematica Sinica,English Series 2019年第9期35卷 1520-1540页

作者： San guo zhu School of Mathematics and Physics Jiangsu University of Technology

Let E be a Moran set on R1 associated with a bounded closed interval J and two sequences(nk)k =1 ^∞ and(Ck =(ck,j)j=1)^nk)k≥1. Let μ be the Moran measure on E associated with a sequence(Pk)k≥1 of positive probability vectors with Pk =(pk,j)j =1,^nk, k ≥ 1. We assume that k≥1 1≤j≤nk^inf min Ck,j>0,k≥1 1≤j≤nk^inf minCk,j>0,k≥1 1≤j≤nk ^inf min pk,j>0. For every n ≥ 1, let αn be αn n optimal set in the quantization for μ of order r ∈(0,∞) and{Pa(αn)}a∈α∈an an arbitrary Voronoi partition with respect to αn. We write Iα(α,μ):=∫Pα(αn)^d(x,αn)^τ dμ(x),α∈αn;J(αn,μ):=α∈αn^minⅠα(α,μ),J(αn,μ):=α∈αn^max Ⅰα(α,μ).We show that J(αn,μ),J(αn,μ) and en^r,r(μ)-en^r +1,r(μ) are of the same order as 1/n en^r ,r(μ), where en^r ,r(μ):=∫d(x,αn)^r dμ(x) is the nth quantization error for μ of order r. In particular, for the class of Moran measures on R1, our result shows that a weaker version of Gersho’s conjecture holds.

关键词： Moran measures quantization error Voronoi partition asymptotic uniformity

Design and optimization of solid rocket motor Finocyl grain using simulated annealing

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航空动力学报 2011年第4期26卷 917-923页

作者： All Kamran LIANG guo-zhu School of Astronautics Beijing University of Aeronautics and Astronautics Beijing 100191 China

The research effort outlined the application of a computer aided design(CAD)-centric technique to the design and optimization of solid rocket motor Finocyl(fin in cylinder) grain using simulated *** proper method for constructing the grain configuration model,ballistic performance and optimizer integration for analysis was *** is a complex grain configuration,requiring thirteen variables to define the *** large number of variables not only complicates the geometrical construction but also optimization *** representation encapsulates all of the geometric entities pertinent to the grain design in a parametric way,allowing manipulation of grain entity(web),performing regression and automating geometrical data *** to avoid local minima and efficient capacity to explore design space makes simulated annealing an attractive choice as *** is demonstrated with a constrained optimization of Finocyl grain geometry for homogeneous,isotropic propellant,uniform regression,and a quasi-steady,bulk mode internal ballistics model that maximizes average thrust for required deviations from neutrality.

关键词： solid rocket motor Finocyl(fin in cylinder) grain internal ballistics simulated annealing computer aided design

Regulation of p53 acetylation

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Science China(Life Sciences) 2017年第3期60卷 321-323页

作者： Wei-guo zhu Department of Biochemistry and Molecular Biology Peking University School of Medical SciencesBeijing 100871China Department of medicine Shenzhen UniversityShenzhen 518060China

As a＂genomic guardian＂,the tumor suppressor p53 plays key roles in maintaining homeostasis under physiological conditions and defending against tumorigenesis upon cellular exposure to internal or external stresses.

关键词： p53 乙酰化肿瘤抑制基因抗肿瘤作用体内平衡生理条件基因组细胞

Bifurcation and chaos of a 4-side fixed rectangular thin plate in electromagnetic and mechanical fields

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 62-71页

作者： Wei-guo zhu Xiang-zhong BAI School of Civil Engineering and Mechanics Yanshan University Qinhuangdao 066004 China Department of Transportation Engineering Huaiyin Institute of Technology Huai 'an 223001 China

We studied the problem of bifurcation and chaos in a 4-side fixed rectangular thin plate in electromagnetic and me-chanical *** on the basic nonlinear electro-magneto-elastic motion equations for a rectangular thin plate and the ex-pressions of electromagnetic forces,the vibration equations are derived for the mechanical loading in a steady transverse magnetic *** the Melnikov function method,the criteria are obtained for chaos motion to exist as demonstrated by the Smale horseshoe *** vibration equations are solved numerically by a fourth-order Runge-Kutta *** bifurcation dia-gram,Lyapunov exponent diagram,displacement wave diagram,phase diagram and Poincare section diagram are obtained.

关键词： Rectangular thin plate Electromagnetic-mechanical coupling Melnikov function method Runge-Kutta method Bifurcation Chaos

ON NODAL LINE OF THE SECOND EIGENFUNCTION OF THE LAPLACIAN OVER CONCAVE DOMAINS IN R^2

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Journal of Systems Science & Complexity 2013年第3期26卷 483-488页

作者： YANG Dong-Hui guo Bao-zhu Department of Mathematics Central South University Academy of Mathematics and Systems Science Academia Sinica

In this note,the Payne's conjecture from convex domains to concave domains is *** is shown that the nodal line N of the second eigenfunction of the Laplacian over some simply connected concave domain Ω in R^2 must in... 详细信息

关键词： Eigenfunction eigenvalue Laplacian.

Numerical Solution to Optimal Feedback Control by Dynamic Programming Approach:A Local Approximation Algorithm

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Journal of Systems Science & Complexity 2017年第4期30卷 782-802页

作者： guo Bao-zhu WU Tao-Tao Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper considers optimal feedback control for a general continuous time finite-dimensional deterministic system with finite horizon cost functional. A practically feasible algorithm to calculate the numerical solution of the optimal feedback control by dynamic programming approach is developed. The highlights of this algorithm are: a) It is based on a convergent constructive algorithm for optimal feedback control law which was proposed by the authors before through an approximation for the viscosity solution of the time-space discretization scheme developed by dynamic programming method; b) The computation complexity is significantly reduced since only values of viscosity solution on some local cones around the optimal trajectory are calculated. Two numerical experiments are presented to illustrate the effectiveness and fastness of the algorithm.

关键词： Curse of dimensionality Hamilton-Jacobi-Bellman equation optimal feedback control upwind finite difference viscosity solutions

Preliminary design and optimization of slotted tube grain for solid rocket motor

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航空动力学报 2008年第12期23卷 2332-2340页

作者： K Nisar LIANG guo-zhu A Kamran School of Astronautics Beijing University of Aeronautics and Astronautics Beijing 100191 China

In this paper,design and optimization technique of slotted tube grain for solid rocket motors has been *** doing so,the design objectives and constraints have been set,geometric parameters identified,performance prediction parameters calculated,thereafter preliminary designs completed and finally optimal design *** model for slotted tube grain configuration has been *** thrust has been taken as the objective function with constraints of burning time,mass of propellant,fixed length and diameter of chamber *** parameter method has been used for calculating the performance prediction parameters.A set of preliminary designs has been completed and an analysis of these results *** all the preliminary results fulfill the design requirements in terms of objective function and constraints,however in order to attain the optimal design,Sequential quadratic programming optimization technique has been *** the slotted tube grain geometry is totally dependent upon various independent variables and each of these variables has a bearing on explicit characteristic of grain designing,hence affects of the independent variables on performance parameters have been examined,thus variation laws have been *** on the variation laws and the analysis of preliminary design results,upper and lower limits have been defined for the independent geometric variables and an initial guess provided for conducting *** attained exhibits that an optimal result has been attained and the value of objective function has been *** the design constraint limits have also been met while ensuring sound values of volumetric loading fraction,web fraction and *** methodology of design and optimization of slotted tube grain for solid rocket motors can be used by engineers as a reference guide for actual design and engineering purposes.

关键词：固体火箭发动机动力系统设计方案

A driving pulse edge modulation technique and its complex programming logic devices implementation

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Frontiers of Information Technology & Electronic Engineering 2015年第12期16卷 1088-1098页

作者： Xiao CHEN Dong-chang QU Yong guo guo-zhu CHEN Electrical Engineering Department Zhejiang University School of Automation and Electrical Engineering Zhejiang University of Science and Technology

With the continual increase in switching speed and rating of power semiconductors, the switching voltage spike becomes a serious problem. This paper describes a new technique of driving pulse edge modulation for insulated gate bipolar transistors(IGBTs). By modulating the density and width of the pulse trains, without regulating the hardware circuit, the slope of the gate driving voltage is controlled to change the switching speed. This technique is used in the driving circuit based on complex programmable logic devices(CPLDs), and the switching voltage spike of IGBTs can be restrained through software, which is easier and more flexible to adjust. Experimental results demonstrate the effectiveness and practicability of the proposed method.

关键词： Driving pulse edge modulation Switching voltage spike Complex programmable logic device(CPLD) Active gate drive