The use of inverse system model as a controller might be an efficient way in controlling nonlinear systems. It is also a known fact that type-2 fuzzy models can represent nonlinear systems better than type-1 fuzzy models. Therefore, an inverse type-2 fuzzy model can be used as a controller for controlling processes with nonlinearities and/or uncertainties. In the case of uncertainties and/or di...

The aim of this paper is to present a new branch and bound method for solving the Multi-Processor Flow-Shop. This method is based on the relaxation of the initial problem to m-machine problems corresponding to centers. Release dates and tails are associated with opérations and machines. The branching scheme consists in ftxing the inputs of a critical center and the lower bounds are those of the...

WCSP is a soft constraint framework with a wide range of applications. Most current complete solvers can be described as a depthfirst branch and bound search that maintain some form of local consistency during the search. However, the known consistencies are unable to solve problems with huge domains because of their time and space complexities. In this paper, we adapt a weaker form of arc cons...

A search for the production of neutral Higgs bosons Φ decaying into ττ final states in pp collisions at a center-of-mass energy of 1.96 TeV is presented. The data, corresponding to an integrated luminosity of up to 348 pb, were collected by the DØ experiment at the Fermilab Tevatron Collider. Since no excess compared to the expectation from standard model processes is found, limits on the produ...

We describe a new method for estimating the evolutionary tree linking a collection of species from their aligned four-state genetic sequences. This method, which can be adapted to provide a branch-and-bound algorithm, is statistically consistent provided the sequences have evolved according to a standard stochastic model of nucleotide mutation. Our approach exploits a recent grouptheoretic desc...

The problem of const.ructing shifts of work for busdrivers from given workblocks is shown to be a minimum cost matching problem. A branch and bound algorithm for this problem is derived which, while not having the guaranteed polynomial time complexity of the well known efficient labelling methods, is shown in extensive compu lational testing to be (1) extremely fast OIl the class of problem whe...

A new exact approach to the stable set problem is presented, which attempts to avoid the pitfalls of existing approaches based on linear and semidefinite programming. The method begins by constructing an ellipsoid that contains the stable set polytope and has the property that the upper bound obtained by optimising over it is equal to the Lovász theta number. This ellipsoid can then be used to ...

We empirically study phase transitions of the asymmetric Traveling Salesman. Using random instances of up to 1,500 cities, we show that many properties of the problem, including the backbone and optimal tour cost, experience sharp transitions as the precision of intercity distances increases across a critical value. We also show that the average computational cost of the well-known branch-and-b...

The problem of finding optimal clustering has not been well covered in literature. Solutions can be found only for special cases, which can be solved in polynomial time. In this paper, we give solution for the general case. The method generates all possible clusterings by a series of merge steps. The clusterings are organized as a minimum redundancy search tree and the optimal clustering is fou...

This paper is concerned with a problem of maximizing the sum of several ratios of functions. We extend an algorithm, which has been designed to solve the sum-of-linear-ratios problem, for solving the sum-of-nonlinear-ratios problem. We also discuss the complexity of the problem and report the results of numerical experiments on the extended algorithm.