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Mathematical Description of the Arming Process of a Fuze Safety System
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作者 范宁军 马宝华 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 1993年第1期62-73,共12页
By determining the state variables of a fuze safety system,some mathematical models——the system of ordinary differential and functional differential equations about the system's arming process are founded in a s... By determining the state variables of a fuze safety system,some mathematical models——the system of ordinary differential and functional differential equations about the system's arming process are founded in a state space.Also,the arming states and restricted relations of the safety factors are described and some demonstrations are presented. 展开更多
关键词 FUZE state spaces/safety and arming system mathematical description
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Mathematical models and expert system for grate-kiln process of iron ore oxide pellet production.Part Ⅱ:Rotary kiln process control 被引量:7
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作者 范晓慧 王祎 陈许玲 《Journal of Central South University》 SCIE EI CAS 2012年第6期1724-1727,共4页
Rotary kiln process for iron ore oxide pellet production is hard to detect and control.Construction of one-dimensional model of temperature field in rotary kiln was described.And the results lay a solid foundation for... Rotary kiln process for iron ore oxide pellet production is hard to detect and control.Construction of one-dimensional model of temperature field in rotary kiln was described.And the results lay a solid foundation for online control.Establishment of kiln process control expert system was presented,with maximum temperature of pellet and gas temperature at the feed end as control cores,and interval estimate as control strategy.Software was developed and put into application in a pellet plant.The results show that control guidance of this system is accurate and effective.After production application for nearly one year,the compressive strength and first grade rate of pellet are increased by 86 N and 2.54%,respectively,while FeO content is 0.05% lowered.This system can reveal detailed information of real time kiln process,and provide a powerful tool for online control of pellet production. 展开更多
关键词 mathematical model expert system one-dimensional temperature field rotary kiln iron ore oxide pellet
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Computer-based Creativity Enhanced Conceptual Design Model for Non-routine Design of Mechanical Systems 被引量:5
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作者 LI Yutong WANG Yuxin DUFFY Alex H B 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第6期1083-1098,共16页
Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure(... Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure(FBS) model is widely used for modeling the conceptual design process, a computer-based creativity enhanced conceptual design model(CECD) for non-routine design of mechanical systems is presented. In the model, the leaf functions in the FBS model are decomposed into and represented with fine-grain basic operation actions(BOA), and the corresponding BOA set in the function domain is then constructed. Choosing building blocks from the database, and expressing their multiple functions with BOAs, the BOA set in the structure domain is formed. Through rule-based dynamic partition of the BOA set in the function domain, many variants of regenerated functional schemes are generated. For enhancing the capability to introduce new design variables into the conceptual design process, and dig out more innovative physical structure schemes, the indirect function-structure matching strategy based on reconstructing the combined structure schemes is adopted. By adjusting the tightness of the partition rules and the granularity of the divided BOA subsets, and making full use of the main function and secondary functions of each basic structure in the process of reconstructing of the physical structures, new design variables and variants are introduced into the physical structure scheme reconstructing process, and a great number of simpler physical structure schemes to accomplish the overall function organically are figured out. The creativity enhanced conceptual design model presented has a dominant capability in introducing new deign variables in function domain and digging out simpler physical structures to accomplish the overall function, therefore it can be utilized to solve non-routine conceptual design problem. 展开更多
关键词 conceptual design non-routine design creative enhance model computer-based approach mathematical expression
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Mathematical models and expert system for grate-kiln process of iron ore oxide pellet production(Part Ⅰ):Mathematical models of grate process 被引量:4
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作者 王祎 范晓慧 陈许玲 《Journal of Central South University》 SCIE EI CAS 2012年第4期1092-1097,共6页
Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematica... Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematical models of temperature distribution,moisture distribution and oxidation degree distribution in pellet bed,with good universality,computation speed and calculation accuracy,are presented based on analysis of heat transfer and physical-chemical reactions during grate process.And real-time visualization of temperature,moisture and oxidation degree distribution in pellet bed during grate process is realized.Model validation is displayed,and the similarity of 91% is proved.The results can reveal real time status on grate,and provide a solid foundation for the subsequent study of artificial intelligence control system of pellet production. 展开更多
关键词 mathematical model temperature distribution moisture distribution oxidation degree distribution iron ore oxide pellet
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An Efficient Content-Based Image Retrieval System Using kNN and Fuzzy Mathematical Algorithm 被引量:3
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作者 Chunjing Wang Li Liu Yanyan Tan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第9期1061-1083,共23页
The implementation of content-based image retrieval(CBIR)mainly depends on two key technologies:image feature extraction and image feature matching.In this paper,we extract the color features based on Global Color His... The implementation of content-based image retrieval(CBIR)mainly depends on two key technologies:image feature extraction and image feature matching.In this paper,we extract the color features based on Global Color Histogram(GCH)and texture features based on Gray Level Co-occurrence Matrix(GLCM).In order to obtain the effective and representative features of the image,we adopt the fuzzy mathematical algorithm in the process of color feature extraction and texture feature extraction respectively.And we combine the fuzzy color feature vector with the fuzzy texture feature vector to form the comprehensive fuzzy feature vector of the image according to a certain way.Image feature matching mainly depends on the similarity between two image feature vectors.In this paper,we propose a novel similarity measure method based on k-Nearest Neighbors(kNN)and fuzzy mathematical algorithm(SBkNNF).Finding out the k nearest neighborhood images of the query image from the image data set according to an appropriate similarity measure method.Using the k similarity values between the query image and its k neighborhood images to constitute the new k-dimensional fuzzy feature vector corresponding to the query image.And using the k similarity values between the retrieved image and the k neighborhood images of the query image to constitute the new k-dimensional fuzzy feature vector corresponding to the retrieved image.Calculating the similarity between the two kdimensional fuzzy feature vector according to a certain fuzzy similarity algorithm to measure the similarity between the query image and the retrieved image.Extensive experiments are carried out on three data sets:WANG data set,Corel-5k data set and Corel-10k data set.The experimental results show that the outperforming retrieval performance of our proposed CBIR system with the other CBIR systems. 展开更多
关键词 Content-based image retrieval KNN fuzzy mathematical algorithm RECALL PRECISION
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Mathematical modeling of elastic inverted pendulum control system 被引量:3
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作者 ChaoXU XinYU 《控制理论与应用(英文版)》 EI 2004年第3期281-282,共2页
Inverted pendulums are important objects of theoretical investigation and experiment in the area of control theory and engineering. The researches concentrate on the rigid finite dimensional models which are described... Inverted pendulums are important objects of theoretical investigation and experiment in the area of control theory and engineering. The researches concentrate on the rigid finite dimensional models which are described by ordinary differential equations (ODEs) .Complete rigidity is the approximation of practical models ; Elasticity should be introduced into mathematical models in the analysis of system dynamics and integration of highly precise controller. A new kind of inverted pendulum, elastic inverted pendulum was proposed, and elasticity was considered. Mathematical model was derived from Hamiltonian principle and variational methods, which were formulated by the coupling of partial differential equations (PDE) and ODE. Because of infinite dimensional, system analysis and control of elastic inverted pendulum is more sophisticated than the rigid one. 展开更多
关键词 Elastic inverted pendulum Hamiltonian principle Variational methods mathematical model Coupling equation array
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3DTS:A 3D tolerancing system based on mathematical definition 被引量:2
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作者 CAO Yan-long LIU Yu-sheng +1 位作者 MAO Jian YANG Jiang-xim 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第11期1810-1818,共9页
Tolerance is almost ubiquitous during the whole product lift cycle and is imperative for seamless integration of CAD and CAM. Based on the mathematical definition of tolerance, a 3D tolerancing system, 3DTS, is presen... Tolerance is almost ubiquitous during the whole product lift cycle and is imperative for seamless integration of CAD and CAM. Based on the mathematical definition of tolerance, a 3D tolerancing system, 3DTS, is presented with its design prin- ciple, system architecture and key functions. The following functional modules, tolerance modeling, semantics interpretation, 3D tolerance analysis, are described in detail. To make the tolerancing system robust and efficient, many techniques such as hierar- chical tolerance representation, rule-based evaluation and non-intersection determination of tolerance zone have been devised. Tested by many samples, this system shows good robustness and practicability. 展开更多
关键词 TOLERANCE mathematical definition CAD/CAM
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A Partial Parallel Airport Gate Assignment Supported by a Knowledge-based System Combined with Mathematical Programming 被引量:2
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作者 Cheng Yu(Center for Transportation Studies, School of Civil and Structural EngineeringNanyang Technological University, Singapore, 2263) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第3期43-61,共19页
The gate assignment at an airport is one of the major activities in airport operations.With the increase of passenger traffic volumes and the number of flights, the complexity of this task and the factors to be consid... The gate assignment at an airport is one of the major activities in airport operations.With the increase of passenger traffic volumes and the number of flights, the complexity of this task and the factors to be considered have increased significantly, and an efficient gate utilizationhas received considerable attention. For overcoming the shortcomings of previous gate assignmentapproaches, this paper presents a partial parallel gate assignment approach, by which more factorsconcerning aircraft and gates can be collsidered at the same time. This paper also presents themethod of using a knowledge-based system combined with a mathematical programming method forgetting an optimized feasible assignment solution. By this way, it is more easily to get the solutionthat satisfies both the static and dynamic situations,and thus it may adapt well to meet the needsof actual use to rea-time operations. An experimental prototype has been implemented, and a casestudy is presented at the end of the paper. 展开更多
关键词 Airport operations Gate assignment Knowledge-based system mathematical programming.
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Development of Mathematical Model of Slag Flow Field and Temperature Field in ESR System 被引量:1
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作者 YANG Yin-dong SOMMERVILLE I D +1 位作者 JOHNSTON R F McLEAN A 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2000年第2期27-31,共5页
The heat transfer phenomena and driving forces of slag bath flow in ESR process were analyzed, and the mathematical models in ESR system were reviewed and evaluated. The electromagnetic force is the main driving force... The heat transfer phenomena and driving forces of slag bath flow in ESR process were analyzed, and the mathematical models in ESR system were reviewed and evaluated. The electromagnetic force is the main driving force for the flow formation in the ESR slag pool, and the temperature difference in the pool creates a convective flow in the system. The shape of the electrode tip has an effect on electromagnetic field distribution in slag pool, thus affects the flow pattern. Finally an improved mathematical model of slag pool flow was proposed. 展开更多
关键词 ESR electromagnetic force buoyancy force flow field temperature field mathematical model
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Basic mathematical model for the normal black smoker system and the hydrothermal megaplume formation 被引量:1
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作者 LIU Longlong ZHAI Shikui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第6期30-40,共11页
A tube model to simulate the normal black smoker system has been built, where the Darcy flow equation, the Ergun equation and the turbulent pipe flow equation are used respectively to describe the dynamic process of d... A tube model to simulate the normal black smoker system has been built, where the Darcy flow equation, the Ergun equation and the turbulent pipe flow equation are used respectively to describe the dynamic process of different key areas in the hydrothermal circulation system. At the same time, a convection - diffuse Equation for the temperature field is used for describe the exchange of thermal energy and the law of temperature variation. Combining the above facts and using efficient mathematical algorithms and programming with the MatLab programming language, the variation curves of temperature, pressure and mass flow rate are determined, while also the dynamic heat equilibrium and pressure equilibrium within the black smoker system are analyzed. On the basis of the model of the normal black smoker system, a megaplume formation model is further built. For instance, the hydrothermal venting plume on the Juan de Fuca Ridge has been simulated and the simulation results are fairly consistent with Baker' s imputed data in 1986. On the basis of the above productive simulation, a series of factors for megaplume formation and the effectiveness of the main parameters of the periodicity of the megaplume formation, temperature and the maximum mass flow rate are systematically discussed. Main conclusions are as follows: The normal black smoker system can evolve into a megaplum eruption. In fact, the passageway of the hydrothermal discharge is blocked by the hydrothermal sediments during the black smoker period, which leads to a hydrothermal fluid accumulation, rise of temperature and increase of buoyancy pressure under the seabed. After a period of 2 - 3 a, the megaplume hydrothermal eruption will occur when the increasing buoyancy pressure is high enough to crack the blockage (cap). Meanwhile, the temperature of the heat source must exceed 500 ℃, while the highest temperature of the eruption fluid may be high up to 413 ℃, which is fairly consistent with the surveying data. If the temperature of the heat source were to be higher than 500 ℃, then the critical period for the megaplume formation could be obviously curtailed to be less than 1 a, while the critical temperature and the maximum mass flow rate are nearly invariable. As the permeability increases, the maximum mass flow rate increases gradually close to a steady value. 展开更多
关键词 normal black smoker megaplume mathematical model simulation for hydrothermal circulation system
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Building up a Mathematical Model of Shaftes System and CAD for Linked Tetra-Shaft and Double-Cantilever Flat Flap Gate 被引量:1
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作者 FuQ满怀 ZhaoZe-bin 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第2期139-146,共8页
Linked tetra shaft and double cantilever flat flap gate is a new type of structure in water conservancy projects,but the traditional method is now adopted in its design.In order to the application and dissemination ... Linked tetra shaft and double cantilever flat flap gate is a new type of structure in water conservancy projects,but the traditional method is now adopted in its design.In order to the application and dissemination of the type of sluice,this paper researches the difficult points of design advance,through researching the motion locus & stress coundition of linked tetra shaft system.The writer will build up the mathmatical model and handle it with the computer.Thus,we can achieve the modern desing on the basis of the software of linked tetra shaft system development. 展开更多
关键词 linked tetra shaft flap gate shaft system mathematical model CAD
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Mathematical Simulation of Dynamic Heat Transfer in a Human-Clothing-Environment System 被引量:1
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作者 刘丽英 《Journal of Donghua University(English Edition)》 EI CAS 2002年第3期127-130,共4页
A mathematical model has been developed to describe the dynamic heat transfer in the clothing microclimate under transient wear conditions. This model is solved numerically by the implicit finite difference method. If... A mathematical model has been developed to describe the dynamic heat transfer in the clothing microclimate under transient wear conditions. This model is solved numerically by the implicit finite difference method. If the physical activity and ambient conditions are specified, the model can predict the thermoregulatory response of the body. Experimental measurements with garments made of fibers with different levels of hygroscopicity are compared with predictions by the model. There is good agreement between prediction and experiment for the temperature of the clothing microclimate. 展开更多
关键词 mathematical model dynamic heat transfer clothing microclimate IMPLICIT FINITE DIFFERENCE method thermoregulatory response.
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MATHEMATICAL PROGRAMS WITH SYSTEM OF GENERALIZED VECTOR QUASI-EQUILIBRIUM CONSTRAINTS IN FC-SPACES 被引量:1
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作者 丁协平 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1257-1268,共12页
In this article, four new classes of systems of generalized vector quasi-equilibrium problems are introduced and studied in FC-spaces without convexity structure. The notions of Ci(x)-FC-partially diagonally quasico... In this article, four new classes of systems of generalized vector quasi-equilibrium problems are introduced and studied in FC-spaces without convexity structure. The notions of Ci(x)-FC-partially diagonally quasiconvex, Ci(x)-FC-quasiconvex, and Ci(x)-FC- quasiconvex-like for set-valued mappings are also introduced in FC-spaces. By applying these notions and a maximal element theorem, the nonemptyness and compactness of solution sets for four classes of systems of generalized vector quasi-equilibrium problems are proved in noncompact FC-spaces. As applications, some new existence theorems of solutions for mathematical programs with system of generalized vector quasi-equilibrium constraints are obtained in FC-spaces. These results improve and generalize some recent known results in literature. 展开更多
关键词 Maximal element system of generalized vector quasi-equilibrium problems mathematical program Ci(x)-FC-partially diagonally quasiconvex Ci(x)-FC-quasiconvex Ci(x)-FC-quasiconvex-like FC-space
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Mathematical Constraints in Multiscale Subgrid-Scale Modeling of Nonlinear Systems 被引量:1
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作者 方乐 葛铭纬 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第3期17-20,共4页
To shed light on the subgrid-seale (SGS) modeling methodology of nonlinear systems such as the Navier-Stokes turbulence, we define the concepts of assumption and restriction in the modeling procedure, which are show... To shed light on the subgrid-seale (SGS) modeling methodology of nonlinear systems such as the Navier-Stokes turbulence, we define the concepts of assumption and restriction in the modeling procedure, which are shown by generalized derivation of three general mathematical constraints for different combinations of restrictions. These constraints are verified numerically in a one-dimensional nonlinear advection equation. This study is expected to inspire future research on the SGS modeling methodology of nonlinear systems. 展开更多
关键词 SGS mathematical Constraints in Multiscale Subgrid-Scale Modeling of Nonlinear systems
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A mathematical model for optimized operation and controlin a CDQ-Boiler system 被引量:1
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作者 De Wang Tao Yang +4 位作者 Zhi Wen Junxiao Feng Ning Kong Qin Wang Weimin Wang 《Journal of University of Science and Technology Beijing》 CSCD 2005年第5期390-393,共4页
Based on analyzing the thermal process of a CDQ (coke dry quenching)-Boiler system, the mathematical model for opti-mized operation and control in the CDQ-Boiler system was developed. It includes a mathematical mode... Based on analyzing the thermal process of a CDQ (coke dry quenching)-Boiler system, the mathematical model for opti-mized operation and control in the CDQ-Boiler system was developed. It includes a mathematical model for heat transferring process in the CDQ unit, a mathematical model for heat transferring process in the boiler and a combustion model for circulating gas in the CDQ-Boiler system. The model was verified by field data, then a series of simulations under several typical operating conditions of CDQ-Boiler were carried on, and in turn, the online relation formulas between the productivity and the optimal circulating gas, and the one between the productivity and the optimal second air, were achieved respectively. These relation equations have been success- fully used in a CDQ-Boiler computer control system in the Baosteel, to realize online optimized guide and control, and meanwhile high efficiency in the CDQ-Boiler system has been achieved. 展开更多
关键词 coke dry quenching-boiler system optimized operation and control mathematical model
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COMPUTER SYSTEM FOR GEOMETRIC MODELING OF GEOLOGIC BODIES AND APPLICATIONS
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作者 Dai, Tagen Mao, Xiancheng 《中国有色金属学会会刊:英文版》 EI CSCD 1998年第4期179-184,共6页
INTRODUCTIONThemodelsofgeometricmodelingofgeologicbodiesbeargeometric,topologicalandattributeinformation[1... INTRODUCTIONThemodelsofgeometricmodelingofgeologicbodiesbeargeometric,topologicalandattributeinformation[1].Bymeansofcomput... 展开更多
关键词 GEOLOGIC BODY data structure mathematical model automatic PLOTTING
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A GENERAL MATHEMATICAL FRAMEWORK OF COMPLEX SYSTEMS(Ⅰ)
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作者 Zan Ting-quan 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第4期385-394,共10页
The fundamental and simplest structure of a complex system is a network.According to this idea,we plan to develop a general methematical framework of complex systems.In this paper,we discuss in detail the concept of s... The fundamental and simplest structure of a complex system is a network.According to this idea,we plan to develop a general methematical framework of complex systems.In this paper,we discuss in detail the concept of systems,a general description of systems:System=(Hardware,Software,Environment),and whole-part relations,including relations between elements and systems,subsystems and systems,and between systems.The rules of operations of systems are given,and the induced transformations between hardware and software of systems are briefly discussed. 展开更多
关键词 complex systems HARDWARE SOFTWARE operations of systems induced transformations mathematical framework
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Dynamic Factor Method of Computing Dynamic Mathematical Model for System Simulation
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作者 老大中 吴娟 +1 位作者 杨策 蒋滋康 《Journal of Beijing Institute of Technology》 EI CAS 2003年第2期143-148,共6页
The computational methods of a typical dynamic mathematical model that can describe the differential element and the inertial element for the system simulation are researched. The stability of numerical solutions of t... The computational methods of a typical dynamic mathematical model that can describe the differential element and the inertial element for the system simulation are researched. The stability of numerical solutions of the dynamic mathematical model is researched. By means of theoretical analysis, the error formulas, the error sign criteria and the error relationship criterion of the implicit Euler method and the trapezoidal method are given, the dynamic factor affecting the computational accuracy has been found, the formula and the methods of computing the dynamic factor are given. The computational accuracy of the dynamic mathematical model like this can be improved by use of the dynamic factor. 展开更多
关键词 system simulation dynamic mathematical model computational method dynamic factor ERROR
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Mathematical modeling of the bellows dispersion system of submunitions
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作者 师娇 唐胜景 高峰 《Journal of Beijing Institute of Technology》 EI CAS 2012年第1期23-30,共8页
A mathematical model of the bellows dispersion system is developed by combining the interior ballistic theory with structural dynamics theory to describe the deformation course of bellows. By analyzing the physical mo... A mathematical model of the bellows dispersion system is developed by combining the interior ballistic theory with structural dynamics theory to describe the deformation course of bellows. By analyzing the physical model of the bellows dispersion system, the dispersion course is divided into three stages. For each stage, mathematical model is built and its terminal conditions are given. The numerical simulation is based on the Runge-Kutta method and differential quadrature method. Simulation results of the model agree with those of the model built by only interior ballistics theory. However, this model is congruous with the actual dispersion course and can more easily determine the dispersion time and submunition displacement. 展开更多
关键词 mathematical model differential quadrature method DEFORMATION DISPERSION submu- nitions
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DYNAMIC MATHEMATICAL MODELING AND APPLICATION FOR PUMPING SYSTEM PERFORMANCE INTEGRATED EVALUATION
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作者 ChenHongxun WangJian WuYuejun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第3期285-288,共4页
A mathematical model is set to evaluate the overall centrifugal pumpingsystem using asynchronous motor as power. This method can be used to affirm system performanceaccording the transform and the aberrance of interio... A mathematical model is set to evaluate the overall centrifugal pumpingsystem using asynchronous motor as power. This method can be used to affirm system performanceaccording the transform and the aberrance of interior parameters and exterior performance curves soas to give a reference to the equipment amelioration. The analysis of emulation experiment datasuggests the model is effectively used. 展开更多
关键词 Pumping system mathematical model Performance evaluation
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