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991.
基于代数等价变换和在KMM算法的框架基础上,在原始-对偶内点方法的牛顿方程里嵌入一种自调节功能.从而对凸二次规划提出了一种新的迭代方向的不可行内点算法,并证明了算法的全局收敛性. 相似文献
992.
In this paper, we introduce systems of vector quasi-equilibrium problems and prove the existence of their solutions. As applications
of our results, we derive the existence theorems for solution of system of vector quasi-saddle point problem, the existences
theorems of a solution of system of generalized quasi-minimax inequalities, the mathematical program with equilibrium constraint,
semi-infinite and bilevel problems. 相似文献
993.
A. Fernández‐Torres P. Posadas A. Marcos‐Fernández A. Rodríguez L. González 《Journal of Polymer Science.Polymer Physics》2007,45(5):544-556
An experimental approach based on the freezing‐point depression of a solvent in a swollen gel has been developed to characterize the structure of rubber networks. This property depends on the conditions required for the formation of crystalline nuclei, which are limited by the elastomer network restrictions. Information about the functionality, spatial distribution, and number of crosslinks can be obtained by the use of this easy and ready experimental method. Application of the tube model of rubber elasticity in the uniaxial stress–strain experiments of natural rubber samples vulcanized with dicumyl peroxide yields the characteristic parameters of the rubber networks, which are in concordance with the network structures predicted by the freezing point method. Finally influence of vulcanization conditions in network structure and its relationship with the mechanical properties was evaluated. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 544–556, 2007 相似文献
994.
Forecasting daily supermarket sales using exponentially weighted quantile regression 总被引:1,自引:0,他引:1
Inventory control systems typically require the frequent updating of forecasts for many different products. In addition to point predictions, interval forecasts are needed to set appropriate levels of safety stock. The series considered in this paper are characterised by high volatility and skewness, which are both time-varying. These features motivate the consideration of forecasting methods that are robust with regard to distributional assumptions. The widespread use of exponential smoothing for point forecasting in inventory control motivates the development of the approach for interval forecasting. In this paper, we construct interval forecasts from quantile predictions generated using exponentially weighted quantile regression. The approach amounts to exponential smoothing of the cumulative distribution function, and can be viewed as an extension of generalised exponential smoothing to quantile forecasting. Empirical results are encouraging, with improvements over traditional methods being particularly apparent when the approach is used as the basis for robust point forecasting. 相似文献
995.
In this paper, we study the problem of existence of zero points for set-valued operators in Banach spaces. We present a simple
condition which can be used to verify that under some conditions, set-valued operators have zero points. Furthermore, we derive
the surjectivity result and the Kakutani fixed point theorem by using this condition.
相似文献
996.
Silvia Bonettini Emanuele Galligani Valeria Ruggiero 《Computational Optimization and Applications》2007,37(1):1-34
This paper deals with the solution of nonlinear programming problems arising from elliptic control problems by an interior
point scheme. At each step of the scheme, we have to solve a large scale symmetric and indefinite system; inner iterative
solvers, with an adaptive stopping rule, can be used in order to avoid unnecessary inner iterations, especially when the current
outer iterate is far from the solution.
In this work, we analyse the method of multipliers and the preconditioned conjugate gradient method as inner solvers for interior
point schemes. We discuss the convergence of the whole approach, the implementation details and report the results of numerical
experimentation on a set of large scale test problems arising from the discretization of elliptic control problems. A comparison
with other interior point codes is also reported.
This research was supported by the Italian Ministry for Education, University and Research (MIUR) projects: FIRB Project:
“Parallel Nonlinear Numerical Optimization PN
2
O” (grant n. RBAU01JYPN, ) and COFIN/PRIN04 Project “Numerical Methods and Mathematical Software for Applications” (grant n. 2004012559, ). 相似文献
997.
Rolando Gárciga Otero Alfredo N. Iusem 《Journal of Mathematical Analysis and Applications》2007,330(1):433-450
We introduce the concept of hypomonotone point-to-set operators in Banach spaces, with respect to a regularizing function. This notion coincides with the one given by Rockafellar and Wets in Hilbertian spaces, when the regularizing function is the square of the norm. We study the associated proximal mapping, which leads to a hybrid proximal-extragradient and proximal-projection methods for nonmonotone operators in reflexive Banach spaces. These methods allow for inexact solution of the proximal subproblems with relative error criteria. We then consider the notion of local hypomonotonicity and propose localized versions of the algorithms, which are locally convergent. 相似文献
998.
We obtain via Schauder's fixed point theorem new results for singular second‐order boundary value problems where our non‐linear term f(t,y,z) is allowed to change sign. In particular, our problem may be singular at y=0, t=0 and/or t=1. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
999.
一类Hysteresis函数的微分(英文) 总被引:2,自引:0,他引:2
1 IntroductionThe theory of hysteresis operators developed in the past 20 years has pro-ved to be a powerful tool fOr solving mathematical probIems in various bran-ches of applications such as solid mechanics, material fatigue, ferromagnetism,phase tIansitbo, and many others. Many models Qf hysteresis operator havebeen constructed (see [1]--[4]). Since hysteresis operators make some good cha-racters (include differentiability) of functional sustain destruction, hysteresisfunctionals are not … 相似文献
1000.
Chan He 《Journal of Mathematical Analysis and Applications》2007,329(2):1260-1272
In this paper, some properties concerning Milman's moduli J(t,X) and S(t,X), including equivalent representations, upper and lower bounds as well as relationship between some geometric properties and these two moduli, are studied. In addition, some sufficient conditions for the fixed point property are presented. 相似文献