The fuzzy optimization problem is one of the prominent topics in the broad area of artificial intelligence. It is applicable in the field of non-linear fuzzy programming. Its application as well as practical realizati...
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The fuzzy optimization problem is one of the prominent topics in the broad area of artificial intelligence. It is applicable in the field of non-linear fuzzy programming. Its application as well as practical realization can been seen in all the real world problems. In this paper a large scale non-linear fuzzy programming problem was solved by hybrid optimization techniques like Line Search (LS), Simulated Annealing (SA) and Pattern Search (PS). An industrial production planning problem with a cubic objective function, eight decision variables and 29 constraints was solved successfully using the LS-SA-PS hybrid optimization techniques. The computational results for the objective function with respect to vagueness factor and level of satisfaction has been provided in the form of 2D and 3D plots. The outcome is very promising and strongly suggests that the hybrid LS-SA-PS algorithm is very efficient and productive in solving the large scale non-linear fuzzy programming problem. (C) 2011 Elsevier Ltd. All rights reserved.
In this paper, a difference scheme with nonuniform meshes is proposed for the initial-boundary problem of the nonlinear parabolic system. It is proved that the difference scheme is second order convergent in both spac...
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In this paper, a difference scheme with nonuniform meshes is proposed for the initial-boundary problem of the nonlinear parabolic system. It is proved that the difference scheme is second order convergent in both space and time.
Single-particle cryo-electron microscopy (cryo-EM) has recently joined X-ray crystallography and NMR spectroscopy as a high-resolution structural method for biological macromolecules. Cryo-EM was selected by Nature Me...
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We propose a domain decomposition method for a system of quasivariational inequalities related to the HJB equation. The monotone convergence of the algorithm is also established.
We propose a domain decomposition method for a system of quasivariational inequalities related to the HJB equation. The monotone convergence of the algorithm is also established.
作者：
CUSHING, JMDepartment of Mathematics
Interdisciplinary Program in Applied Mathematics Building 89 University of Arizona Tucson Arizona 85721 USA
A size-structured model for the dynamics of a cannibalistic population is derived under the assumption that cannibals (successfully) attack only smaller bodied victims, as is generally the case in the biological world...
A size-structured model for the dynamics of a cannibalistic population is derived under the assumption that cannibals (successfully) attack only smaller bodied victims, as is generally the case in the biological world. In addition to the resulting size-dependent death rate, the model incorporates the positive feedback mechanism resulting from the added resource energy obtained by the cannibal from the consumption of the victim. From the nonlinear partial integro-differential equation model, it is shown how to obtain a complete analysis of the global dynamics of the total population biomass. This analysis yields many dynamical features that have been attributed to cannibalism in the literature, including density self-regulation, a “life-boat strategy” phenomenon by which a population avoids extinction by practicing cannibalism under circumstances when it would otherwise go extinct, and multiple stable positive equilibrium states and hysteresis.
作者：
CUSHING, JMDepartment of Mathematics
Interdisciplinary Program in Applied Mathematics Building 89 University of Arizona Tucson Arizona 85721 USA
This paper deals with the problem of relating physiological properties of individual organisms to the dynamics at the total population level. A general nonlinear matrix difference equation is described which accounts ...
This paper deals with the problem of relating physiological properties of individual organisms to the dynamics at the total population level. A general nonlinear matrix difference equation is described which accounts for the dynamics of stage-structured populations under the assumption that individuals in the populations can be placed into well defined descriptive stages. Density feedback is modeled through an assumption that (stage-specific) fertilities and transitions are proportional to a resource uptake functional which is dependent upon a total weighted population size. It is shown how, if stage-specific differences in mortality are insignificant compared to stage-specific differences in fertility and inter-stage transitions, a nonlinear version of the strong ergodic theorem of demography mathematically separates the population level dynamics from the dynamics of the stage distribution vector, which is shown to stabilize independently of the population level dynamics. The nonlinear dynamics at the population level are governed by a key parameter π that encapsulates the stage-specific parameters and thereby affords a means by which population level dynamics can be linked to properties of individual organisms. The method is applied to a community of stagestructured populations competing for a common limiting resource, and it is seen how the parameter π determines the competitively superior species. An example of size structured competitors illustrates how the method can relate the competitive success of a species to such size-specific properties as resource conversion efficiencies and allocation fractions for individual growth and reproduction, largest adult body size, and size at birth and maturation.
The operational mechanics of a production process for the manufacture of glass sheet is investigated. A general formulation is given in which the sheet is considered as an elasticoviscous continuous beam with slope/de...
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The operational mechanics of a production process for the manufacture of glass sheet is investigated. A general formulation is given in which the sheet is considered as an elasticoviscous continuous beam with slope/deflection constraints. Detailed analytical solutions are obtained for the limiting cases of purely viscous and purely elastic materials. Conditions are derived which process parameters and boundary values must satisfy. A critical sheet viscosity and temperature calculated from one of these are found to be in excellent agreement with process observations.
This paper is concerned with the numerical approximations of semi-linear stochastic partial differential equations of elliptic type in ***gence analysis and error estimates are presented for the numerical solutions b...
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This paper is concerned with the numerical approximations of semi-linear stochastic partial differential equations of elliptic type in ***gence analysis and error estimates are presented for the numerical solutions based on the spectral *** results demonstrate the good performance of the spectral method.
In 1964 Chadwick and Windle published a detailed investigation of the secular equation governing the propagation of surface waves in a semi-infinite,isotropic, heat-conducting elastic body the surface of which is trac...
In 1964 Chadwick and Windle published a detailed investigation of the secular equation governing the propagation of surface waves in a semi-infinite,isotropic, heat-conducting elastic body the surface of which is traction-free and either at constant uniform temperature or thermally insulated. The purpose of the present paper is first to remedy a defect in the work of Chadwick and Windle and then to extend the scope of their analysis by allowing the transmitting body to exchange heat with a constant-temperature environment. The defect arises from the insufficiency of the criteria used to decide whether or not a branch of the algebraic function defined by the rationalized secular equation represents a surface wave. When it is corrected the non-uniqueness of the surface-wave solutions found by Chadwick and Windle is removed and there exists precisely one quasi-elastic surface wave for all frequencies and for all values of the heat-transfer coefficient appearing in the thermal boundary condition, including the extremes considered in the original study.
An algorithm for the inverse of a general tridiagonal matrix is presented. For a tridiagonal matrix having the Doolittle factorization, an inversion algorithm is established. The algorithm is then generalized to deal ...
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An algorithm for the inverse of a general tridiagonal matrix is presented. For a tridiagonal matrix having the Doolittle factorization, an inversion algorithm is established. The algorithm is then generalized to deal with a general tridiagonal matrix without any restriction. Comparison with other methods is provided, indicating low computational complexity of the proposed algorithm, and its applicability to general tridiagonal matrices.
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