排序方式: 共有18条查询结果,搜索用时 0 毫秒
1.
R. Baker Kearfott 《Mathematical Programming》1998,83(1-3):89-100
Various algorithms can compute approximate feasible points or approximate solutions to equality and bound constrained optimization
problems. In exhaustive search algorithms for global optimizers and other contexts, it is of interest to construct bounds
around such approximate feasible points, then to verify (computationally but rigorously) that an actual feasible point exists
within these bounds. Hansen and others have proposed techniques for proving the existence of feasible points within given
bounds, but practical implementations have not, to our knowledge, previously been described. Various alternatives are possible
in such an implementation, and details must be carefully considered. Also, in addition to Hansen’s technique for handling
the underdetermined case, it is important to handle the overdetermined case, when the approximate feasible point corresponds
to a point with many active bound constraints. The basic ideas, along with experimental results from an actual implementation,
are summarized here.
This work was supported in part by National Science Foundation grant CCR-9203730. 相似文献
2.
3.
4.
5.
Z. D. Whetstone K. J. Kearfott 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(3):629-639
Conventional explosives are relatively easy to obtain and may cause massive harm to people and property. There are several tools employed by law enforcement to detect explosives, but these can be subverted. Active neutron interrogation is a viable alternative to those techniques, and includes: fast neutron analysis, thermal neutron analysis, pulsed fast/thermal neutron analysis, neutron elastic scatter, and fast neutron radiography. These methods vary based on neutron energy and radiation detected. A thorough review of the principles behind, advantages, and disadvantages of the different types of active neutron interrogation is presented. 相似文献
6.
Ralph Baker Kearfott Sowmya Muniswamy Yi Wang Xinyu Li Qian Wang 《Journal of Global Optimization》2013,57(4):1091-1111
Minimax problems can be approached by reformulating them into smooth problems with constraints or by dealing with the non-smooth objective directly. We focus on verified enclosures of all globally optimal points of such problems. In smooth problems in branch and bound algorithms, interval Newton methods can be used to verify existence and uniqueness of solutions, to be used in eliminating regions containing such solutions, and point Newton methods can be used to obtain approximate solutions for good upper bounds on the global optimum. We analyze smooth reformulation approaches, show weaknesses in them, and compare reformulation to solving the non-smooth problem directly. In addition to analysis and illustrative problems, we exhibit the results of numerical computations on various test problems. 相似文献
7.
Zhou Qingzhi Shubayr Nasser Carmona Marco Standen Timothy M. Kearfott Kimberlee J. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):673-680
Journal of Radioanalytical and Nuclear Chemistry - Flow-through radon sources were widely utilized in the calibration of radon equipment and radon studies. In this paper a broken 266Ra source which... 相似文献
8.
It is known that there are feasible algorithms for minimizing convex functions, and that for general functions, global minimization
is a difficult (NP-hard) problem. It is reasonable to ask whether there exists a class of functions that is larger than the
class of all convex functions for which we can still solve the corresponding minimization problems feasibly. In this paper,
we prove, in essence, that no such more general class exists. In other words, we prove that global optimization is always
feasible only for convex objective functions. 相似文献
9.
R. Baker Kearfott 《Journal of Global Optimization》1992,2(3):259-280
In this paper, we propose modifications to a prototypical branch and bound algorithm for nonlinear optimization so that the algorithm efficiently handles constrained problems with constant bound constraints. The modifications involve treating subregions of the boundary identically to interior regions during the branch and bound process, but using reduced gradients for the interval Newton method. The modifications also involve preconditioners for the interval Gauss-Seidel method which are optimal in the sense that their application selectively gives a coordinate bound of minimum width, a coordinate bound whose left endpoint is as large as possible, or a coordinate bound whose right endpoint is as small as possible. We give experimental results on a selection of problems with different properties. 相似文献
10.