some oscillation theorems for systems of even order quasilinear partial differential equations in this paper new sufficient conditions are obtained for oscillation for the solutions of the systems of a class even order quasilinear partial functional differential equations of neutral type these results are illustrated by some examples

deterministic approximations to stochastic production problems in this paper we consider deterministic approximations to a nonsequential stochastic production problem with setup costs we show that for the most commonly used probability distributions of the demands the relative error bounds tend to be very small we also consider a sequential stochastic problem without setup costs and discuss its relationship to the nonsequential case throughout the paper we present limited computational results and indicate topics for further research

an application of swarm optimization to nonlinear programming particle swarm optimization pso is an optimization technique based on population which has similarities to other evolutionary algorithms it is initialized with a population of random solutions and searches for optima by updating generations particle swarm optimization has become the hotspot of evolutionary computation because of its excellent performance and simple implementation after introducing the basic principle of the pso a particle swarm optimization algorithm embedded with constraint fitness priority based ranking method is proposed in this paper to solve nonlinear programming problem by designing the fitness function and constraints handling method the proposed pso can evolve with a dynamic neighborhood and varied inertia weighted value to find the global optimum the results from this preliminary investigation are quite promising and show that this algorithm is reliable and applicable to almost all of the problems in multiple dimensional nonlinear and complex constrained programming it is proved to be efficient and robust by testing some example and benchmarks of the constrained nonlinear programming problems

oscillation of even order partial differential equations with distributed deviating arguments some kamenev type oscillation criteria are established for a class of boundary value problems associated with even order partial differential equations with distributed deviating arguments our approach is to reduce the high dimensional oscillation problem to a one dimensional oscillation one and the general means developed by philos and wong is used as the main tool the results obtained here extend and improve some known results in the literature

forced oscillation of solutions of certain hyperbolic equations of neutral type some oscillation properties of solutions of certain hyperbolic equations of neutral type are studied and sufficient conditions for the oscillation of the solutions of a boundary value problem in a cylindrical domain are given

expected value of fuzzy variable and fuzzy expected value models this paper will present a novel concept of expected values of fuzzy variables which is essentially a type of choquet integral and coincides with that of random variables in order to calculate the expected value of general fuzzy variable a fuzzy simulation technique is also designed finally we construct a spectrum of fuzzy expected value models and integrate fuzzy simulation neural network and genetic algorithms to produce a hybrid intelligent algorithm for solving general fuzzy expected value models

oscillation criteria for second order nonlinear differential equations involving general means consider the second order nonlinear differential equation e y a t f y 0 where a t c 0 f y c1 f y 0 and yf y 0 for y 0 furthermore f y also satisfies either a superlinear or a sublinear condition which covers the nonlinear function f y y y 1 with 1 and 0 1 respectively commonly known as the emden fowler case here the coefficient function a t is allowed to be negative for arbitrarily large values of t kamenev type oscillation criteria involving integral averages for the linear equations l y a t y 0 are extended to the nonlinear equation e by using more general means the results extend similar results on general means by philos for the linear equation l and also results based upon kamenev s integral averaging method concerning the nonlinear equation e

an oscillation criterion for second order sublinear differential equations abstract an oscillation criterion is given for the second order sublinear differential equation y a t f y 0 where a t is not assumed to be non negative and f y is non decreasing in y and yf y 0 for y 0 f y also satisfies a sublinear condition which includes the special case f y y y sgn y 0 this result extends earlier oscillation theorems of philos and the first author

integral inequalities and second order linear oscillation on the interval 0 a u 0 below by a solution we mean a non trivial solution a solution is oscillatory if it has an infinite number of zeros numerous oscillation criteria are known and diversified approaches have proved fruitful among these is the use of the associated riccati equation although the theory of differential and integral inequalities has been used by some investigators see e g hartman 4 71 the authors believe that it has not been fully exploited the non oscillation of 1 1 is equivalent to the existence of a solution of the associated riccati equation on a half line thus one technique of proving oscillation is to show that any solution of the riccati equation diverges to i co at a finite point the theory of differential and integral inequalities comes in handy in the estimation of the growth of such a solution below we describe some known results that are relevant to results established in this paper although these are stated here for the case i co in the rest of the paper we consider both cases a 0 and a 00 it is well known that if q is large in the mean then 1 1 is oscillatory a typical example of such a criterion is due to fite leighton and wintner if

erratum to an optimal gap theorem here we shall use the same notations of the original paper the references to equations lemmas propositions theorems are with respect to the paper unless stated otherwise the argument provided for the proof of proposition 3 1 is not complete it overlooks the fact that the solution 2 form x t of the problem 3 1 may contain non trivial 2 0 and 0 2 parts hence proposition 3 1 needs a correction we thank gilles carron for pointing out this oversight in the original proof of proposition 3 1 and his comments we also thank luen fai tam for helpful related discussions we refer interested reader to 5 for an alternate proof of theorem 1 2 since the preservation of the positivity for solution 2 forms solving the problem 3 1 in the paper without knowing that the 2 form being 1 1 type seems elusive even for the 1 1 part projection of the 2 form solutions we replace 3 1 with the following initial boundary value problem on 1 1 form let be a smooth bounded domain in m for a given point p let be the unit outward normal in a small neighborhood near p we

possibility distributions of fuzzy decision variables obtained from possibilistic linear programming problems abstract in this paper several kinds of possibility distributions of fuzzy variables are studied in possibilistic linear programming problems to reflect the inherent fuzziness in fuzzy decision problems interval and triangular possibility distributions are used to express the non interactive cases between the fuzzy decision variables and exponential possibility distributions are used to represent the interrelated cases possibilistic linear programming problems based on exponential possibility distributions become non linear optimization problems in order to solve optimization problems easily algorithms for obtaining center vectors and distribution matrices in sequence are proposed by the proposed algorithms the possibility distribution of fuzzy decision variables can be obtained

convergent results about the use of fuzzy simulation in fuzzy optimization problems we discuss the convergence of fuzzy simulation as it is employed in fuzzy optimization problems several convergence concepts for sequences of fuzzy variables are defined such as convergence in optimistic value a new approach to approximating essentially bounded fuzzy variables with continuous possibility distributions is introduced applying the proposed approximation method to our previous work we prove three convergence theorems about the use of fuzzy simulation in computing the credibility of a fuzzy event finding the optimistic value of a return function and calculating the expected value of a fuzzy variable

fuzzy sets as a basis for a theory of possibility the theory of possibility described in this paper is related to the theory of fuzzy sets by defining the concept of a possibility distribution as a fuzzy restriction which acts as an elastic constraint on the values that may be assigned to a variable more specifically if f is a fuzzy subset of a universe of discourse u u which is characterized by its membership function f then a proposition of the form x is f where x is a variable taking values in u induces a possibility distribution tx which equates the possibility of x taking the value u to f u the compatibility of u with f in this way x becomes a fuzzy variable which is associated with the possibility distribution tx in much the same way as a random variable is associated with a probability distribution in general a variable may be associated both with a possibility distribution and a probability distribution with the weak connection between the two expressed as the possibility probability consistency principle a thesis advanced in this paper is that the imprecision that is intrinsic in natural languages is in the main possibilistic rather than probabilistic in nature thus by employing the concept of a possibility distribution a proposition p in a natural language may be translated into a procedure which computes the probability distribution of a set of attributes which are implied by p several types of conditional translation rules are discussed and in particular a translation rule for propositions of the form x is f is possible where is a number in the interval 0 1 is formulated and illustrated by examples

plurisubharmonic functions and the structure of complete kahler manifolds with nonnegative curvature in this paper we study global properties of continuous plurisubharmonic functions on complete noncompact kahler manifolds with nonnegative bisectional curvature and their applications to the structure of such manifolds we prove that continuous plurisubharmonic functions with reasonable growth rate on such manifolds can be approximated by smooth plurisubharmonic functions through the heat flow deformation optimal liouville type theorem for the plurisubharmonic functions as well as a splitting theorem in terms of harmonic functions and holomorphic functions are established the results are then applied to prove several structure theorems on complete noncompact kahler manifolds with nonnegative bisectional or sectional curvature

oscillation criterion for half linear differential equations with periodic coefficients abstract in this paper we present an oscillation criterion for second order half linear differential equations with periodic coefficients the method is based on the nonexistence of a proper solution of the related modified riccati equation our result can be regarded as an oscillatory counterpart to the nonoscillation criterion by sugie and matsumura 2008 these two theorems provide a complete half linear extension of the oscillation criterion of kwong and wong 2003 dealing with the hill s equation

multiproduct single machine production system with stochastic scrapped production rate partial backordering and service level constraint in this paper a multiproduct single machine production system under economic production quantity epq model is studied in which the existence of only one machine causes a limited production capacity for the common cycle length of all products the production defective rates are random variables shortages are allowed and take a combination of backorder and lost sale and there is a service rate constraint for the company the aim of this research is to determine the optimal production quantity the allowable shortage level and the period length of each product such that the expected total cost including holding shortage production setup and defective items costs is minimized the mathematical model of the problem is derived for which the objective function is proved to be convex then a derivative approach is utilized to obtain the optimal solution finally two numerical examples in each of which a sensitivity analysis is performed on the model parameters are provided to illustrate the practical usage of the proposed methodology

aggregate production planning with multiple objectives in a fuzzy environment abstract this work presents a novel fuzzy linear programming flp method for solving the aggregate production planning app problem with multiple objectives where the product price unit cost to subcontract work force level production capacity and market demands are fuzzy in nature also discussed herein are limitations of applying the conventional mathematical programming technique to medium term production planning in addition the specific flp model is proposed moreover an interactive solution procedure is developed to provide a compromise solution finally a numerical example is presented to demonstrate the effectiveness of the proposed procedure the proposed procedure allows a decision maker to model a problem according to the current information the proposed model is more appropriate than the unfuzzy problem formulation in terms of reflecting a realistic situation consequently the information costs are generally decreased

using greedy clustering method to solve capacitated location routing problem with fuzzy demands abstract in this paper the capacitated location routing problem with fuzzy demands clrp fd is considered in clrp fd facility location problem flp and vehicle routing problem vrp are observed simultaneously indeed the vehicles and the depots have a predefined capacity to serve the customers that have fuzzy demands to model this problem a fuzzy chance constrained programming model of that is designed based upon the fuzzy credibility theory to solve this problem a greedy clustering method gcm including the stochastic simulation is proposed to obtain the best value of the dispatcher preference index of the model and to analyze its influence on the final solution numerical experiments are carried out finally to show the performance of the greedy clustering method associated results are compared with the lower bound of the solutions

sharp differential estimates of li yau hamilton type for positive p p forms on kahler manifolds in this paper we study the heat equation of hodge laplacian deformation of p p forms on a kahler manifold after identifying the condition and establishing that the positivity of a p p form solution is preserved under such an invariant condition we prove the sharp differential harnack in the sense of liyau hamilton estimates for the positive solutions of the hodge laplacian heat equation we also prove a nonlinear version coupled with the kahler ricci flow and some interpolating matrix differential harnack type estimates for both the kahler ricci flow and the ricci flow 2011 wiley periodicals inc

a robust lot sizing problem with ill known demands the paper deals with a lot sizing problem with ill known demands modeled by fuzzy intervals whose membership functions are possibility distributions for the values of the uncertain demands optimization criteria in the setting of possibility theory that lead to choose robust production plans under fuzzy demands are given some algorithms for determining optimal robust production plans with respect to the proposed criteria and for evaluating production plans are provided some computational experiments are presented

modeling fuzzy multi period production planning and sourcing problem with credibility service levels a great deal of research has been done on production planning and sourcing problems most of which concern deterministic or stochastic demand and cost situations and single period systems in this paper we consider a new class of multi period production planning and sourcing problem with credibility service levels in which a manufacturer has a number of plants and subcontractors and has to meet the product demand according to the credibility service levels set by its customers in the proposed problem demands and costs are uncertain and assumed to be fuzzy variables with known possibility distributions the objective of the problem is to minimize the total expected cost including the expected value of the sum of the inventory holding and production cost in the planning horizon because the proposed problem is too complex to apply conventional optimization algorithms we suggest an approximation approach aa to evaluate the objective function after that two algorithms are designed to solve the proposed production planning problem the first is a pso algorithm combining the aa and the second is a hybrid pso algorithm integrating the aa neural network nn and pso finally one numerical example is provided to compare the effectiveness of the proposed two algorithms

oscillation criteria for boundary value problems of high order partial functional differential equations in this paper a class of boundary value problems associated with high order partial functional differential equations with distributed deviating arguments is investigated some oscillation criteria of solutions to the problem are developed our approach is to reduce the multi dimensional oscillation problem to a one dimensional oscillation one by employing some integral means of solutions and introducing some parameter functions one illustrative example is considered

oscillation properties for systems of hyperbolic differential equations of neutral type abstract sufficient conditions are established for the oscillations of systems of hyperbolic differential equations of the form 2 t 2 p t u i x t r 1 d r t u i x t r a i t u i x t j 1 m k 1 s a ijk t u j x k t q i x t u i x t j 1 m h 1 l q ijh x t u j x h t x t 0 g i 1 2 m where is a bounded domain in rn with a piecewise smooth boundary and is the laplacian in euclidean n space rn

on kamenev type oscillation theorems for second order differential equations with damping abstract oscillation criteria for the nonlinear second order ordinary differential equation with damping x p t x f x 0 are given the results are extensions of integral averaging technique of kamenev and include earlier results of yeh yan and chen