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81.
Logic-Based Modeling and Solution of Nonlinear Discrete/Continuous Optimization Problems 总被引:2,自引:0,他引:2
This paper presents a review of advances in the mathematical programming approach to discrete/continuous optimization problems.
We first present a brief review of MILP and MINLP for the case when these problems are modeled with algebraic equations and
inequalities. Since algebraic representations have some limitations such as difficulty of formulation and numerical singularities
for the nonlinear case, we consider logic-based modeling as an alternative approach, particularly Generalized Disjunctive
Programming (GDP), which the authors have extensively investigated over the last few years. Solution strategies for GDP models
are reviewed, including the continuous relaxation of the disjunctive constraints. Also, we briefly review a hybrid model that
integrates disjunctive programming and mixed-integer programming. Finally, the global optimization of nonconvex GDP problems
is discussed through a two-level branch and bound procedure. 相似文献
82.
吴慧卓 《纯粹数学与应用数学》2003,19(1):16-21
典型的进化策略受自然进化过程的启发而成为求解全局优化问题的重要方法。传统的ES变异算子作为一个主要的进化技术是建立在正态分布的随机变量基础上的,本文提出了基于指数分布的进化策略由于采用了新的变异算子有效地减少了产生探试解的成本,从而优于传统的进化策略。 相似文献
83.
考虑带调和势的超临界非线性Schroedinger方程,解决了该方程整体解和爆破解存在所依赖的初始条件的最佳分界门槛.通过构造两类强制变分问题和建立局部不变半流,运用势井方法和凹方法,获得了该方程在两个不同的空间中的整体解和爆破解的最佳门槛条件. 相似文献
84.
姜正禄 《武汉大学学报(理学版)》1997,(1)
给出了带有硬相互作用的相对论Boltzmann方程初值问题整体解存在性的证明 相似文献
85.
The constrained optimization problem with a quadratic cost functional and two quadratic equality constraints has been studied by Bar-on and Grasse, with positive-definite matrix in the objective. In this note, we shall relax the matrix in the objective to be positive semidefinite. A necessary and sufficient condition to characterize a local optimal solution to be global is established. Also, a perturbation scheme is proposed to solve this generalized problem. 相似文献
86.
Li Chen Ling Hsiao Gerald Warnecke 《应用数学学报(英文版)》2007,23(1):9-28
This paper considers a kind of strongly coupled cross diffusion parabolic system,which can be usedas the multi-dimensional Lyumkis energy transport model in semiconductor science.The global existence andlarge time behavior are obtained for smooth solution to the initial boundary value problem.When the initialdata are a small perturbation of an isothermal stationary solution,the smooth solution of the problem under theinsulating boundary condition,converges to that stationary solution exponentially fast as time goes to infinity. 相似文献
87.
M K Parida Nita Sinha B Adhikary B Allanach A Alok K S Babu B Brahmachari D Choudhury E J Chun P K Das A Ghosal D Hitlin W S Hou S Kumar H N Li E Ma S K Majee G Majumdar B Mishra G Mohanty S Nandi H Pas M K Parida S D Rindani J P Saha N Sahu Y Sakai S Sen C Sharma C D Sharma S Shalgar N N Singh S Uma Sankar N Sinha R Sinha F Simonetto R Srikanth R Vaidya 《Pramana》2006,67(5):849-860
This is the report of flavor physics and model building working group at WHEPP-9. While activites in flavor physics have been
mainly focused on B-physics, those in model building have been primarily devoted to neutrino physics. We present summary of working group discussions
carried out during the workshop in the above fields, and also briefly review the progress made in some projects subsequently. 相似文献
88.
In the present paper,we investigate the well-posedness of the global solution for the Cauchy problem of generalized long-short wave equations.Applying Kato's method for abstract quasi-linear evolution equations and a priori estimates of solution,we get the existence of globally smooth solution. 相似文献
89.
Bruni C. Bruni R. De Santis A. Iacoviello D. Koch G. 《Journal of Optimization Theory and Applications》2002,115(1):67-96
In this paper, a procedure is presented which allows the optimal reconstruction of images from blurred noisy data. The procedure relies on a general Bayesian approach, which makes proper use of all the available information. Special attention is devoted to the informative content of the edges; thus, a preprocessing phase is included, with the aim of estimating the jump sizes in the gray level. The optimization phase follows; existence and uniqueness of the solution is secured. The procedure is tested against simple simulated data and real data. 相似文献
90.
M. N. Smolyakov 《General Relativity and Gravitation》2007,39(1):41-53
A model with one compact extra dimension and a scalar field of Brans–Dicke type in the bulk is discussed. It describes two branes with non-zero tension embedded into the space-time with flat background. This setup allows one to use a very simple method for stabilization of the size of extra dimension. It appears that the four-dimensional Planck mass is expressed only through parameters of the scalar field potentials on the branes. 相似文献