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Grey Qualitative Modeling and Control Method for Subjective Uncertain Systems
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作者 Peng Wang Shu-Jie Li +1 位作者 Yan Lv Zong-Hai Chen 《International Journal of Automation and computing》 EI CSCD 2015年第1期70-76,共7页
A new approach to model and control an unknown system using subjective uncertain rules is proposed. This method is established by combining the grey system theory and the qualitative simulation method. The proposed ap... A new approach to model and control an unknown system using subjective uncertain rules is proposed. This method is established by combining the grey system theory and the qualitative simulation method. The proposed approach mainly contains three steps. In the first step, subjective uncertain rules are accumulated gradually during cognizing the system; the mapping relations between the system inputs and outputs are built and represented using the grey qualitative matrix in the second step; in the third step,the generalized whitening function is defined to realize the transformation between qualitative and quantitative information. Besides the theoretical results, two sets of simulations based on a water level control system are conducted comparatively to demonstrate the effectiveness of the proposed method. The water level expectation is set to be constant in the first set, while it changes in the second set. The simulation results show that the proposed method tracks the water level expectation well. By combining the proposed method with proportional-integral-derivative(PID) or fuzzy logic controller(FLC), it can be concluded that the system can reach the stable state more quickly and the overshoot can also be reduced compared to using PID or FLC alone. 展开更多
关键词 Uncertain system qualitative modeling knowledge representation subjective uncertainty grey qualitative method
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DEFICIENT INFORMATION MODELING OF MECHANICAL PRODUCTS FOR CONCEPTUAL SHAPE DESIGN 被引量:3
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作者 Liu Jihong Shu Huilin CAD Center,Huazhong University of Science and Technology,Wuhan 430074,China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第1期1-5,26,共6页
In allusion to the deficient feature of product information in conceptualdesign, a framework of deficient information modeling for conceptual shape design is put forward,which includes qualitative shape modeling (a qu... In allusion to the deficient feature of product information in conceptualdesign, a framework of deficient information modeling for conceptual shape design is put forward,which includes qualitative shape modeling (a qualitative solid model), uncertain shape modeling (anuncertain relation model) and imprecise shape modeling (an imprecise region model). In theframework, the qualitative solid model is the core, which represents qualitatively (using symbols)the conceptual shapes of mechanical products. The uncertain relation model regarding domainrelations as objects and the imprecise region model regarding domains as objects are used to dealwith the uncertain and imprecise issues respectively, which arise from qualitative shape modeling orexist in product information itself. 展开更多
关键词 Conceptual shape design qualitative solid model Spatial cognition
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Multi-objective intelligent coordinating optimization blending system based on qualitative and quantitative synthetic model 被引量:3
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作者 王雅琳 马杰 +2 位作者 桂卫华 阳春华 张传福 《Journal of Central South University of Technology》 EI 2006年第5期552-557,共6页
A multi-objective intelligent coordinating optimization strategy based on qualitative and quantitative synthetic model for Pb-Zn sintering blending process was proposed to obtain optimal mixture ratio. The mechanism a... A multi-objective intelligent coordinating optimization strategy based on qualitative and quantitative synthetic model for Pb-Zn sintering blending process was proposed to obtain optimal mixture ratio. The mechanism and neural network quantitative models for predicting compositions and rule models for expert reasoning were constructed based on statistical data and empirical knowledge. An expert reasoning method based on these models were proposed to solve blending optimization problem, including multi-objective optimization for the first blending process and area optimization for the second blending process, and to determine optimal mixture ratio which will meet the requirement of intelligent coordination. The results show that the qualified rates of agglomerate Pb, Zn and S compositions are increased by 7.1%, 6.5% and 6.9%, respectively, and the fluctuation of sintering permeability is reduced by 7.0%, which effectively stabilizes the agglomerate compositions and the permeability. 展开更多
关键词 Pb-Zn sintering blending process qualitative and quantitative synthetic model multi-objectiveoptimization area optimization intelligent coordination
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Qualitative Knowledge Based Discrete Rod Model with Simulation Case
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作者 周海英 董素荣 李龙俊 《Journal of Beijing Institute of Technology》 EI CAS 2010年第1期14-18,共5页
Constructing a qualitative model for discrete rods warhead,the kinematics analysis and dynamics analysis of the rods are completed.On the basis of the qualitative model of discrete rods,a simulation case is provided.T... Constructing a qualitative model for discrete rods warhead,the kinematics analysis and dynamics analysis of the rods are completed.On the basis of the qualitative model of discrete rods,a simulation case is provided.The qualitative simulation result shows that hexagon cross section shape of rod will receive the lowest air drag while by means of better preplaced dip angle,controlling the rotation velocity of the rod and keeping every rod with identical dip angle to the axis of warhead will make the rod get a lateral direction velocity so as to have the rod gain identical casting initial velocity in its length direction.Simulation experiment shows that when dip angle of preplaced discrete rod is 6°,the damage cycle reaches the optimal value. 展开更多
关键词 qualitative model discrete rod qualitative simulation
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Modeling Multisource-heterogeneous Information Based on Random Set and Fuzzy Set Theory
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作者 文成林 徐晓滨 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期87-92,共6页
This paper presents a new idea, named as modeling multisensor-heterogeneous information, to incorporate the fuzzy logic methodologies with mulitsensor-multitarget system under the framework of random set theory. First... This paper presents a new idea, named as modeling multisensor-heterogeneous information, to incorporate the fuzzy logic methodologies with mulitsensor-multitarget system under the framework of random set theory. Firstly, based on strong random set and weak random set, the unified form to describe both data (unambiguous information) and fuzzy evidence (uncertain information) is introduced. Secondly, according to signatures of fuzzy evidence, two Bayesian-markov nonlinear measurement models are proposed to fuse effectively data and fuzzy evidence. Thirdly, by use of "the models-based signature-matching scheme", the operation of the statistics of fuzzy evidence defined as random set can be translated into that of the membership functions of relative point state variables. These works are the basis to construct qualitative measurement models and to fuse data and fuzzy evidence. 展开更多
关键词 random set theory DATA fuzzy evidence fuzzy membership functions qualitative measurement model.
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A Qualitative Model of the Interaction of Sexual Behavior and Hormone Gene Transcription in Male Blue Gourami during Reproduction
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作者 Gad Degani 《Journal of Biophysical Chemistry》 2020年第4期43-50,共8页
In the present study, a model is suggested to describe hormone control in male blue gourami (<i><span style="font-family:Verdana;">Trichogaster trichopterus</span></i><span style=&... In the present study, a model is suggested to describe hormone control in male blue gourami (<i><span style="font-family:Verdana;">Trichogaster trichopterus</span></i><span style="font-family:Verdana;">) along the gonadotropic brain</span><span style="font-size:10pt;font-family:Verdana;">-</span><span style="font-size:10pt;font-family:Verdana;">pituitary</span><span style="font-size:10pt;font-family:Verdana;">- </span><span style="font-size:10pt;font-family:Verdana;">gonad axis (BPG axis) and the hypothalamic-pituitary-somatotropic axis (HPS axis). This model is based on the cloning</span><span style="font-size:10.0pt;font-family:""><span style="font-family:Verdana;"> and transcription of genes encoding hormones of the two axes involved in spermatogenesis during blue gourami reproduction. Gene transcription is affected by environmental, biological, </span><span style="font-family:Verdana;">and behavioral factors. Mature males were examined in two different stages—nonreproductive in high-density habitats and reproductive in low-density </span><span style="font-family:Verdana;">habitats. Based on gene transcription, gonadotropin-releasing hormone 1 (GnRH1) was involved in controlling spermatogenesis (spermatogonia to spermatids) via the BPG axis in nonreproductive and reproductive stages by controlling follicle-stimulating hormone (FSH), 11-ketotestosterone (11KT) and 17</span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-estradiol (E</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">). However, GnRH3 had a larger effect during the reproductive stage via the BPG axis (spermatids to sperm) on luteinizing hormone (LH), 11KT, and 17</span><i><span style="font-family:Verdana;">α</span></i></span><span style="font-size:10pt;font-family:Verdana;">-</span><span style="font-size:10pt;font-family:Verdana;">hydroxyprogesterone (17P). At the same time, the HPS axis was involved in spermatogenesis via pituitary adenylate cyclase-activating polypeptide (PACAP) and its related peptide PRP (formerly known as GHRH-like peptide) in the brain, and growth hormone (GH) in the pituitary affected synthesis of insulin-like growth factor 1 (IGF1) in the liver.</span> 展开更多
关键词 qualitative Model Anabantidae HORMONE Gene Trichogaster SPERMATOGENESIS SPERM GNRH 11-Ketotestosterone Gonadotropic Brain Pituitary Gonad Axis
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The Resolution of the Great 20th Century Debate in the Foundations of Mathematics 被引量:1
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作者 Edgar E. Escultura 《Advances in Pure Mathematics》 2016年第3期144-158,共15页
The paper resolves the great debate of the 20th century between the three philosophies of mathematics-logicism, intuitionism and formalism—founded by Bertrand Russell and A. N. Whitehead, L. E. J. Brouwer and David H... The paper resolves the great debate of the 20th century between the three philosophies of mathematics-logicism, intuitionism and formalism—founded by Bertrand Russell and A. N. Whitehead, L. E. J. Brouwer and David Hilbert, respectively. The issue: which one provides firm foundations for mathematics? None of them won the debate. We make a critique of each, consolidate their contributions, rectify their weakness and add our own to resolve the debate. The resolution forms the new foundations of mathematics. Then we apply the new foundations to assess the status of Hilbert’s 23 problems most of which in foundations and find out which ones have been solved, which ones have flawed solutions that we rectify and which ones are open problems. Problem 6 of Hilbert’s problems—Can physics be axiomatized?—is answered yes in E. E. Escultura, Nonlinear Analysis, A-Series: 69(2008), which provides the solution, namely, the grand unified theory (GUT). We also point to the resolution of the 379-year-old Fermat’s conjecture (popularly known as Fermat’s last theorem) in E. E. Escultura, Exact Solutions of Fermat’s Equations (Definitive Resolution of Fermat’s Last Theorem), Nonlinear Studies, 5(2), (1998). Likewise, the proof of the 274-year-old Goldbach’s conjecture is in E. E. Escultura, The New Mathematics and Physics, Applied Mathematics and Computation, 138(1), 2003. 展开更多
关键词 Axiom of Choice Banach-Tarski Paradox Goldbach’s Conjecture LOGICISM CONSTRUCTIVISM Fermat’s Conjecture Field Axioms Formalism qualitative Modelling Rational Thought SELF-REFERENCE
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A CONFIGURATION SYSTEM FOR FASTENER DESIGN(AN APPROACH TOWARDS COMPUTER AIDED CONCEPTUAL DESIGN)
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作者 Guang Zhong Mike Dooner 《Computer Aided Drafting,Design and Manufacturing》 1995年第1期52-63,共4页
The paper describes research aimed at developing a configuration system to support theconceptual design of mechanical fasteners. A prototype configuration system has been developedwhich allows designers to interactive... The paper describes research aimed at developing a configuration system to support theconceptual design of mechanical fasteners. A prototype configuration system has been developedwhich allows designers to interactively configure fastener designs using geometric and functionalicons , freely without regard to physical constraints, with the aim of forming candidate designs.Candidate designs are then passed to the qualitative modeller which uses qualrtative reasoningtechniques to evaluate the configuration. Supporting the above design procedure is a knowledgebase which contains object descriptions of fasteners and fastener features (given in terms ofgeometry, function, performance, material,installation). Design rules (expressing spatial andcasual relationships of fastener features),which are required during the evaluation of candidatefastener configurations, are also contained in the knowledge base. 展开更多
关键词 CONFIGURATION conceptual design visualisation qualitative modelling qualrtativereasoning functional modelling.
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QUALITATIVE ANALYSIS FOR A MATHEMATICAL MODEL OF AIDS
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作者 井竹君 刘正荣 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1993年第4期302-316,共15页
In this paper a mathematical model of AIDS is investigated.The conditions of the existence of equilibria and local stability of equilibria are given.The existences of transcritical bifurcation and Hopf bifurcation are... In this paper a mathematical model of AIDS is investigated.The conditions of the existence of equilibria and local stability of equilibria are given.The existences of transcritical bifurcation and Hopf bifurcation are also considered.in particular,the conditions for the existence of Hopf bifurcation can be given in terms of the coefficients of the characteristic equation.The method extends the application of the Hopf bifurcation theorem to higher differential equations which occur in biological models,chemical models,and epidemiological models etc. 展开更多
关键词 qualitative ANALYSIS FOR A MATHEMATICAL MODEL OF AIDS REAL HOPF
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What Prompts the People's Bank of China to Change Its Monetary Policy Stance?Evidence from a Discrete Choice Model 被引量:6
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作者 Laurent L.Pauwels 《China & World Economy》 SCIE 2008年第6期1-21,共21页
In the present paper, we model the policy stance of the People's Bank of China (PBC) as a latent variable, and the discrete changes in the reserve requirement ratio, policy interest rates, and the scale of open mar... In the present paper, we model the policy stance of the People's Bank of China (PBC) as a latent variable, and the discrete changes in the reserve requirement ratio, policy interest rates, and the scale of open market operations are taken as signals of movement of this latent variable. We run a discrete choice regression that relates these observed indicators of policy stance to major trends of macroeconomic and financial developments, which are represented by common factors extracted from a large number of variables. The predicted value of the estimated model can then be interpreted as the implicit policy stance of the PBC. In a second step, we estimate how much of the variation in the PBC' s implicit stance can be explained by measures of its policy objectives on inflation, growth and financial stability. We find that deviations of CPI inflation from an implicit target and deviations of broad money growth from the announced targets, but not output gaps, figure significantly in the PBC's policy changes. 展开更多
关键词 monetary policy People's Bank of China qualitative response models
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Parametric sensitivity analysis of precipitation and temperature based on multi-uncertainty quantification methods in the Weather Research and Forecasting model 被引量:3
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作者 DI ZhenHua 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第5期876-898,共23页
Sensitivity analysis(SA) has been widely used to screen out a small number of sensitive parameters for model outputs from all adjustable parameters in weather and climate models, helping to improve model predictions b... Sensitivity analysis(SA) has been widely used to screen out a small number of sensitive parameters for model outputs from all adjustable parameters in weather and climate models, helping to improve model predictions by tuning the parameters. However, most parametric SA studies have focused on a single SA method and a single model output evaluation function, which makes the screened sensitive parameters less comprehensive. In addition, qualitative SA methods are often used because simulations using complex weather and climate models are time-consuming. Unlike previous SA studies, this research has systematically evaluated the sensitivity of parameters that affect precipitation and temperature simulations in the Weather Research and Forecasting(WRF) model using both qualitative and quantitative global SA methods. In the SA studies, multiple model output evaluation functions were used to conduct various SA experiments for precipitation and temperature. The results showed that five parameters(P3, P5, P7, P10, and P16) had the greatest effect on precipitation simulation results and that two parameters(P7 and P10) had the greatest effect for temperature. Using quantitative SA, the two-way interactive effect between P7 and P10 was also found to be important, especially for precipitation. The microphysics scheme had more sensitive parameters for precipitation, and P10(the multiplier for saturated soil water content) was the most sensitive parameter for both precipitation and temperature. From the ensemble simulations, preliminary results indicated that the precipitation and temperature simulation accuracies could be improved by tuning the respective sensitive parameter values, especially for simulations of moderate and heavy rain. 展开更多
关键词 Multi-uncertainty quantification methods qualitative parameters screening Quantitative sensitivity analysis Weather Research and Forecasting model
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