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A Gravity Forward Modeling Method based on Multiquadric Radial Basis Function 被引量:1
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作者 LIU Yan LV Qingtian +4 位作者 HUANG Yao SHI Danian MENG Guixiang YAN Jiayong ZHANG Yongqian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第S01期62-64,共3页
It is one of the most important part to build an accurate gravity model in geophysical exploration.Traditional gravity modelling is usually based on grid method,such as difference method and finite element method wide... It is one of the most important part to build an accurate gravity model in geophysical exploration.Traditional gravity modelling is usually based on grid method,such as difference method and finite element method widely used.Due to self-adaptability lack of division meshes and the difficulty of high-dimensional calculation. 展开更多
关键词 geophysical exploration gravity forward modeling mesh-free method radial basis function
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Grey GM(1,1) Model with Function-Transfer Method for Wear Trend Prediction and its Application 被引量:11
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作者 LUO You xin 1 , PENG Zhu 2 , ZHANG Long ting 1 , GUO Hui xin 1 , CAI An hui 1 1Department of Mechanical Engineering, Changde Teachers University, Changde 415003, P.R. China 2 Engineering Technology Board, Changsha Cigare 《International Journal of Plant Engineering and Management》 2001年第4期203-212,共10页
Trend forecasting is an important aspect in fault diagnosis and work state supervision. The principle, where Grey theory is applied in fault forecasting, is that the forecast system is considered as a Grey system; the... Trend forecasting is an important aspect in fault diagnosis and work state supervision. The principle, where Grey theory is applied in fault forecasting, is that the forecast system is considered as a Grey system; the existing known information is used to infer the unknown information's character, state and development trend in a fault pattern, and to make possible forecasting and decisions for future development. It involves the whitenization of a Grey process. But the traditional equal time interval Grey GM (1,1) model requires equal interval data and needs to bring about accumulating addition generation and reversion calculations. Its calculation is very complex. However, the non equal interval Grey GM (1,1) model decreases the condition of the primitive data when establishing a model, but its requirement is still higher and the data were pre processed. The abrasion primitive data of plant could not always satisfy these modeling requirements. Therefore, it establishes a division method suited for general data modeling and estimating parameters of GM (1,1), the standard error coefficient that was applied to judge accuracy height of the model was put forward; further, the function transform to forecast plant abrasion trend and assess GM (1,1) parameter was established. These two models need not pre process the primitive data. It is not only suited for equal interval data modeling, but also for non equal interval data modeling. Its calculation is simple and convenient to use. The oil spectrum analysis acted as an example. The two GM (1,1) models put forward in this paper and the new information model and its comprehensive usage were investigated. The example shows that the two models are simple and practical, and worth expanding and applying in plant fault diagnosis. 展开更多
关键词 Grey GM (1 1) model fault diagnosis function transfer method trend prediction
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Predictive functional control based on fuzzy T-S model for HVAC systems temperature control 被引量:6
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作者 Hongli LU Lei JIA +1 位作者 Shulan KONG Zhaosheng ZHANG 《控制理论与应用(英文版)》 EI 2007年第1期94-98,共5页
In heating, ventilating and air-conditioning (HVAC) systems, there exist severe nonlinearity, time-varying nature, disturbances and uncertainties. A new predictive functional control based on Takagi-Sugeno (T-S) f... In heating, ventilating and air-conditioning (HVAC) systems, there exist severe nonlinearity, time-varying nature, disturbances and uncertainties. A new predictive functional control based on Takagi-Sugeno (T-S) fuzzy model was proposed to control HVAC systems. The T-S fuzzy model of stabilized controlled process was obtained using the least squares method, then on the basis of global linear predictive model from T-S fuzzy model, the process was controlled by the predictive functional controller. Especially the feedback regulation part was developed to compensate uncertainties of fuzzy predictive model. Finally simulation test results in HVAC systems control applications showed that the proposed fuzzy model predictive functional control improves tracking effect and robustness. Compared with the conventional PID controller, this control strategy has the advantages of less overshoot and shorter setting time, etc. 展开更多
关键词 T-S fuzzy model Predictive functional control Least squares method HVAC systems
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Homotopy Analysis Method for Solving Biological Population Model 被引量:2
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作者 A.A.M.Arafa S.Z.Rida H.Mohamed 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第11期797-800,共4页
In this paper,the homotopy analysis method (HAM) is applied to solve generalized biological populationmodels.The fractional derivatives are described by Caputo's sense.The method introduces a significant improveme... In this paper,the homotopy analysis method (HAM) is applied to solve generalized biological populationmodels.The fractional derivatives are described by Caputo's sense.The method introduces a significant improvementin this field over existing techniques.Results obtained using the scheme presented here agree well with the analyticalsolutions and the numerical results presented in Ref.[6].However,the fundamental solutions of these equations stillexhibit useful scaling properties that make them attractive for applications. 展开更多
关键词 biological populations model fractional calculus homotopy analysis method Mittag-Leffier function
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Numerical method of slope failure probability based on Bishop model 被引量:3
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作者 苏永华 赵明华 张月英 《Journal of Central South University of Technology》 EI 2008年第1期100-105,共6页
Based on Bishop's model and by applying the first and second order mean deviations method, an approximative solution method for the first and second order partial derivatives of functional function was deduced acc... Based on Bishop's model and by applying the first and second order mean deviations method, an approximative solution method for the first and second order partial derivatives of functional function was deduced according to numerical analysis theory. After complicated multi-independent variables implicit functional function was simplified to be a single independent variable implicit function and rule of calculating derivative for composite function was combined with principle of the mean deviations method, an approximative solution format of implicit functional function was established through Taylor expansion series and iterative solution approach of reliability degree index was given synchronously. An engineering example was analyzed by the method. The result shows its absolute error is only 0.78% as compared with accurate solution. 展开更多
关键词 Bishop mechanical model failure probability of slope mean deviation method implicit function Taylor series dump of open-pit
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Dynamic stability analysis of porous functionally graded beams under hygro-thermal loading using nonlocal strain gradient integral model 被引量:2
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作者 Pei ZHANG P.SCHIAVONE Hai QING 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第12期2071-2092,共22页
We present a study on the dynamic stability of porous functionally graded(PFG)beams under hygro-thermal loading.The variations of the properties of the beams across the beam thicknesses are described by the power-law ... We present a study on the dynamic stability of porous functionally graded(PFG)beams under hygro-thermal loading.The variations of the properties of the beams across the beam thicknesses are described by the power-law model.Unlike most studies on this topic,we consider both the bending deformation of the beams and the hygro-thermal load as size-dependent,simultaneously,by adopting the equivalent differential forms of the well-posed nonlocal strain gradient integral theory(NSGIT)which are strictly equipped with a set of constitutive boundary conditions(CBCs),and through which both the stiffness-hardening and stiffness-softening effects of the structures can be observed with the length-scale parameters changed.All the variables presented in the differential problem formulation are discretized.The numerical solution of the dynamic instability region(DIR)of various bounded beams is then developed via the generalized differential quadrature method(GDQM).After verifying the present formulation and results,we examine the effects of different parameters such as the nonlocal/gradient length-scale parameters,the static force factor,the functionally graded(FG)parameter,and the porosity parameter on the DIR.Furthermore,the influence of considering the size-dependent hygro-thermal load is also presented. 展开更多
关键词 nonlocal strain gradient integral model dynamic stability porous functionally graded(PFG)shear deformation beam size-dependent hygro-thermal load generalized differential quadrature method(GDQM)
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Thermal kinetic analysis of a complex process from a solid-state reaction by deconvolution procedure from a new calculation method and related thermodynamic functions of Mn_(0.90)Co_(0.05)Mg_(0.05)HPO_4?3H_2O 被引量:1
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作者 Chuchai SRONSRI Banjong BOONCHOM 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第9期1887-1902,共16页
Three individual peaks of thermal solid-state reaction processes of the synthesized Mn0.90Co0.05Mg0.05HPO4?3H2O were observed corresponding to dehydration I,dehydration II and polycondensation processes.An alternative... Three individual peaks of thermal solid-state reaction processes of the synthesized Mn0.90Co0.05Mg0.05HPO4?3H2O were observed corresponding to dehydration I,dehydration II and polycondensation processes.An alternative method for the calculation of the extent of conversion was proposed from the peak area of the individual DTG peak after applying the best fitting deconvolution function(Frazer–Suzuki function).An iterative integral isoconversional equation was used to compute the values of the apparent activation energy Eαand they were found to be 65.87,78.16 and 119.32 kJ/mol for three peaks,respectively.Each individual peak was guaranteed to be a single-step kinetic system with its unique kinetic parameters.The reaction mechanism functions were selected by the comparison between experimental and model plots.The results show that the first,second and final individual peaks were two-dimensional diffusion of spherical symmetry(D2),three-dimensional diffusion of spherical symmetry(D3)and contracting cylinder(cylindrical symmetry,R2)mechanisms.Pre-exponential factor values of 3.91×106,1.35×107 and 2.15×107 s?1 were calculated from the Eαvalues and reaction mechanisms.The corresponded standard thermodynamic functions of the transition-state(activated)complexes were determined and found to agree well with the experimental data. 展开更多
关键词 solid-state reaction calculation method complex reaction Frazer–Suzuki function experimental and model plots
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EFFICIENT ESTIMATION OF FUNCTIONAL-COEFFICIENT REGRESSION MODELS WITH DIFFERENT SMOOTHING VARIABLES 被引量:5
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作者 张日权 李国英 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期989-997,共9页
In this article,a procedure for estimating the coefficient functions on the functional-coefficient regression models with different smoothing variables in different coefficient functions is defined.First step,by the l... In this article,a procedure for estimating the coefficient functions on the functional-coefficient regression models with different smoothing variables in different coefficient functions is defined.First step,by the local linear technique and the averaged method,the initial estimates of the coefficient functions are given.Second step,based on the initial estimates,the efficient estimates of the coefficient functions are proposed by a one-step back-fitting procedure.The efficient estimators share the same asymptotic normalities as the local linear estimators for the functional-coefficient models with a single smoothing variable in different functions.Two simulated examples show that the procedure is effective. 展开更多
关键词 Asymptotic normality averaged method different smoothing variables functional-coefficient regression models local linear method one-step back-fitting procedure
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Universal triple I fuzzy reasoning algorithm of function model based on quotient space 被引量:1
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作者 Lu Qiang Shen Guanting and Liu Xiaoping 《Computer Aided Drafting,Design and Manufacturing》 2012年第1期49-60,共12页
Aiming at the deficiencies of analysis capacity from different levels and fuzzy treating method in product function modeling of conceptual design, the theory of quotient space and universal triple I fuzzy reasoning me... Aiming at the deficiencies of analysis capacity from different levels and fuzzy treating method in product function modeling of conceptual design, the theory of quotient space and universal triple I fuzzy reasoning method are introduced, and then the function modeling algorithm based on the universal triple I fuzzy reasoning method is proposed. Firstly, the product function granular model based on the quotient space theory is built, with its function granular representation and computing rules defined at the same time. Secondly, in order to quickly achieve function granular model from function requirement, the function modeling method based on universal triple I fuzzy reasoning is put forward. Within the fuzzy reasoning of universal triple I method, the small-distance-activating method is proposed as the kernel of fuzzy reasoning; how to change function requirements to fuzzy ones, fuzzy computing methods, and strategy of fuzzy reasoning are respectively investigated as well; the function modeling algorithm based on the universal triple I fuzzy reasoning method is achieved. Lastly, the validity of the function granular model and function modeling algorithm is validated. Through our method, the reasonable function granular model can be quickly achieved from function requirements, and the fuzzy character of conceptual design can be well handled, which greatly improves conceptual design. 展开更多
关键词 conceptual design function modeling fuzzy reasoning universal triple I method
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FURTHER RESEARCH ON THE SPLINE MODEL METHOD OF KED ANALYSIS IN A PLANAR FLEXIBLE LINKAGE
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作者 管伯良 张程 《Journal of China Textile University(English Edition)》 EI CAS 1994年第1期66-74,共9页
This paper relates to the deep research on the Splinc Model Method of KED analysis. With the use of cubic B-splinc function as a link’s transverse deflection interpolation function, the principle of virtual displacem... This paper relates to the deep research on the Splinc Model Method of KED analysis. With the use of cubic B-splinc function as a link’s transverse deflection interpolation function, the principle of virtual displacement is presented as a basic theory for the general formulation of the equations of motion, and thus abandoned the kinematic assumption and the instantaneous structure assumption which arc used in the Spline Model Method. In thc same time, the nonlinear terms sue as coupling terms between thc rigid body motion and elastic deformation arc included. New member’s spline models are established. Mass matrix, Coriolis mass matrix, normal and tangential mass matrix, linear stiffness matrix, nonlinear stiffness matrix and rotation matrix arc derived. The kinematic differential equations of a member and system are deduced in the end. The Newmark direct integration method is used as the solution scheme of the kinematic differential equations to get the periodic response. 展开更多
关键词 link mechanisms SPLINE functions elastic deformation SPLINE model method KED analysis SPLINE model PLANAR flexible linkage.
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Numerical modeling calculation for the spatial distribution characteristics of horizontal field transfer functions
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作者 龚绍京 陈化然 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2001年第6期676-684,共9页
Applying 3-dimension finite difference method, the distribution characteristics of horizontal field transfer functions for rectangular conductor have been computed, and the law of distribution for Re-part and Im-part ... Applying 3-dimension finite difference method, the distribution characteristics of horizontal field transfer functions for rectangular conductor have been computed, and the law of distribution for Re-part and Im-part has been given. The influences of source field period, the conductivity, the buried depth and the length of the conductor on the transfer functions were studied. The extrema of transfer functions appear at the center, the four corners and around the edges of conductor, and move with the edges. This feature demonstrates that around the edges are best places for transfer functions' observation. 展开更多
关键词 numerical modeling 3-D finite difference method horizontal field transfer function spatial distribution characteristics
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Ground movements modeling applying adjusted influence function
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作者 Agnieszka Malinowska Ryszard Hejmanowski Huayang Dai 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第2期243-249,共7页
Mathematical modeling of surface deformations caused by underground mining operation is commonly carried out with use of empirical,numerical or stochastic models.One of the most frequently applied model for prediction... Mathematical modeling of surface deformations caused by underground mining operation is commonly carried out with use of empirical,numerical or stochastic models.One of the most frequently applied model for prediction of ground deformation in many countries is Knothe model.The model developed by Knothe belongs to the stochastic methods and is based on the influence function.In China a prediction method named Probability Integration Method(PIF)was established by Liu Baochen and Liao Guohua based on the stochastic medium theory.Modified version of that model allows to predict ground movements caused by mining operation in extremely complex technical and geological conditions.That model is commonly applied for coal,metal ore and salt deposits.The article presents several modifications of the mathematical model used in China and Poland.This model is very widespread in the world,therefore the generalizations proposed in the article can be implemented for the purposes of prediction surface deformations for various types of deposits in many countries.The presented generalizations were then tested on specific examples of coal mining,copper ore mining and rock salt deposit.The obtained results indicate high efficiency of methods based on the influence function in complex geological and mining conditions. 展开更多
关键词 MINING operation modelING of surface deformations Stochastic models PROBABILITY integration method Influence function SALT HARD coal MINING copper ORE MINING
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Extended Jacobian Elliptic Function Expansion Method and Its Applications in Biology
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作者 Emad H. M. Zahran Mostafa M. A. Khater 《Applied Mathematics》 2015年第7期1174-1181,共8页
In this work, an extended Jacobian elliptic function expansion method is proposed for constructing the exact solutions of nonlinear evolution equations. The validity and reliability of the method are tested by its app... In this work, an extended Jacobian elliptic function expansion method is proposed for constructing the exact solutions of nonlinear evolution equations. The validity and reliability of the method are tested by its applications to Dynamical system in a new Double-Chain Model of DNA and a diffusive predator-prey system which play an important role in biology. 展开更多
关键词 Extended JACOBIAN Elliptic function Expansion method Dynamical SYSTEM in a New DOUBLE-CHAIN model of DNA A Diffusive PREDATOR-PREY SYSTEM Traveling WAVE SOLUTIONS Solitary WAVE SOLUTIONS
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Determination of Material Parameters of EVA Foam under Uniaxial Compressive Testing Using Hyperelastic Models
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作者 Nattapong Sangkapong Fasai Wiwatwongwana Nattawit Promma 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期800-804,共5页
The objective of this research was to determine the mechanical parameter from EVA foam and also investigate its behavior by using Blatz-Ko,Neo-Hookean,Mooney model and experimental test.The physical characteristic of ... The objective of this research was to determine the mechanical parameter from EVA foam and also investigate its behavior by using Blatz-Ko,Neo-Hookean,Mooney model and experimental test.The physical characteristic of EVA foam was also evaluated by scanning electron microscopy(SEM).The results show that Blatz-Ko and Neo-Hookean model can fit the curve at 5%and 8%strain,respectively.The Mooney model can fit the curve at 50%strain.The modulus of rigidity evaluated from Mooney model is 0.0814±0.0027 MPa.The structure of EVA foam from SEM image shows that EVA structure is a closed cell with homogeneous porous structure.From the result,it is found that Mooney model can adjust the data better than other models.This model can be applied for mechanical response prediction of EVA foam and also for reference value in engineering application. 展开更多
关键词 hyperelastic models modulus of rigidity EVA foam curve fitting method strain energy function uniaxial compressive testing
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Three-Di mensional Model for Strip Hot Rolling 被引量:6
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作者 ZHANG Guo-min XIAO Hong WANG Chun-hua 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第1期23-26,共4页
A three-dimensional model for strip hot rolling was developed, in which the plastic deformation of strip, the thermal crown of rolls, roll deflection and flattening were calculated by rigid-plastic finite element meth... A three-dimensional model for strip hot rolling was developed, in which the plastic deformation of strip, the thermal crown of rolls, roll deflection and flattening were calculated by rigid-plastic finite element method, finite difference method, influential function method and elastic finite element method respectively. The roll wear was taken into consideration. The model can provide detailed information such as rolling pressure distribution, contact pressure distribution between backup rolls and work rolls, deflection and flattening of work rolls, lateral distribution of strip thickness, and lateral distribution of front and back tensions. The finish rolling on a 1 450 mm hot strip mill was simulated. 展开更多
关键词 strip hot rolling model finite difference method influential function method finite element method
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Exact Solutions of Fractional-Order Biological Population Model 被引量:13
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作者 A.M.A.El-Sayed S.Z.Rida A.A.M.Arafa 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期992-996,共5页
In this paper, the Adomian's decomposition method (ADM) is presented for finding the exact solutions of a more general biological population models. A new solution is constructed in power series. The fractional der... In this paper, the Adomian's decomposition method (ADM) is presented for finding the exact solutions of a more general biological population models. A new solution is constructed in power series. The fractional derivatives are described in the Caputo sense. To illustrate the reliability of the method, some examples are provided. 展开更多
关键词 biological populations model fractional Calculus decomposition method Mittag-Leffier function
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Risk assessment model of tunnel water inrush based on improved attribute mathematical theory 被引量:9
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作者 YANG Xiao-li ZHANG Sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期379-391,共13页
Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel... Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility. 展开更多
关键词 tunnel water inrush risk assessment model attribute mathematical theory nonlinear measurement function similar weight method
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A STUDY OF B-P UNIFIED VISCOPLASTIC CONSTITUTIVE MODEL 被引量:3
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作者 M. Zhao, G. Zhang, K.S. Zhang and L. Y. XuDepartment of Aeroengines Thermal Power, Northwestern Polytechnical University, Xi’an 710072, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2002年第5期460-464,共5页
By combining the Bodner-Partom constitutive model and equivalent stressfunction, finite element methods and program on analyzing non-elastic deformation and stress forthermal viscoplastic material are studied in this ... By combining the Bodner-Partom constitutive model and equivalent stressfunction, finite element methods and program on analyzing non-elastic deformation and stress forthermal viscoplastic material are studied in this paper, and it's the first time that this materialmodel is used in a kind of engineering software-MARC. Thermal viscoplastic behavior of hightemperature alloy GH536 specimen with gap is analyzed by this program. The research results show itis feasible to analyze thermal viscoplastic behavior of specimen or structure by applying B-P model. 展开更多
关键词 effective stress function(ESF) VISCOPLASTIC Bodner-Partom model (B-Pmodel) finite element method (FEM) constitutive equation
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Stability of Stochastic Logistic Model with Ornstein-Uhlenbeck Process for Cell Growth of Microorganism in Fermentation Process 被引量:2
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作者 Tawfiqullah Ayoubi 《Applied Mathematics》 2019年第8期659-675,共17页
Current research is concerned with the stability of stochastic logistic equation with Ornstein-Uhlenbeck process. First, this research proves that the stochastic logistic model with Ornstein-Uhlenbeck process has a po... Current research is concerned with the stability of stochastic logistic equation with Ornstein-Uhlenbeck process. First, this research proves that the stochastic logistic model with Ornstein-Uhlenbeck process has a positive solution. After that, it also introduces the sufficient conditions for stochastically stability of stochastic logistic model for cell growth of microorganism in fermentation process for positive equilibrium point by using Lyapunov function. In addition, this research establishes the sufficient conditions for zero solution as mentioned in Appendix A due to the cell growth of microorganism &mu;max, which cannot be negative in fermentation process. Furthermore, for numerical simulation, current research uses the 4-stage stochastic Runge-Kutta (SRK4) method to show the reality of the results. 展开更多
关键词 STABILITY FERMENTATION PROCESS ORNSTEIN-UHLENBECK PROCESS Logistic model Lyapunov function 4-Stage Stochastic RUNGE-KUTTA method
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Optimization Mathematical Model of Pile Forces for Offshore Piled Breasting Dolphins 被引量:1
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作者 周锡礽 王乐芹 +1 位作者 王晖 朱福明 《海洋工程:英文版》 EI 2004年第4期567-575,共9页
An optimization mathematical model of the pile forces for piled breasting dolphins in the open sea under various loading conditions is presented. The optimum layout with the well distributed pile forces and the least ... An optimization mathematical model of the pile forces for piled breasting dolphins in the open sea under various loading conditions is presented. The optimum layout with the well distributed pile forces and the least number of piles is achieved by the multiplier penalty function method. Several engineering cases have been calculated and compared with the result of the conventional design method. It is shown that the number of piles can be reduced at least by 10%~20% and the piles' bearing state is improved greatly. 展开更多
关键词 piled breasting dolphin mathematical model multiplier penalty function method optimization design
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