In this paper we consider the problem of estimating the propagation delays of the transmitted signals in an asynchronous direct-sequence code division multiple access (DS-CDMA) system operating over a fading channel. Two estimators based on subspace techniques are compared and the Cram er-Rao Bound, a lower bound on the variance of any unbiased estimator, is derived. Special attention is paid t...

Résumé 174

Sequential search methods characterized by a dynamically changing number of features included or eliminated at each step, henceforth "floating" methods, are presented. They are shown to give very good results and to be computationally more effective than the branch and bound method.

Dynamically composed systems are able to incorporate new components as they execute. Therefore, conngurations of these systems are not fully elaborated until at least the time that they are executed, and they are perhaps never fully elaborated. Such incomplete conngurations are termed partially bound conngurations. Although partially bound, it is still important to be able to analyse these conn...

Utilization bound is a well-known concept introduced in the seminal paper of Liu and Layland, which provides a simple and practical way to test the schedulability of a real-time task set. The original utilization bound for the fixed-priority scheduler was given as a function of the number of tasks in the periodic task set. In this paper, we define the utilization bound as a function of the info...

The performance of Branch-and-Bound algorithms is severely impaired by the presence of symmetric optima in a given problem. We describe a method for the automatic detection of formulation symmetries in MINLP instances. A software implementation of this method is used to conjecture the group structure of the problem symmetries of packing equal circles in a square. We provide a proof of the conje...

This paper studies the solving of finite-domain action planning problems with discrete action costs and soft constraints. For sequential optimal planning, a symbolic perimeter database heuristic is addressed in a bucket implementation of A*. For computing net-benefits, we propose symbolic branch-and-bound search together with some search refinements. The net-benefit we optimize is the total ben...

jahanshahloo has suggested a method for the solving linear programming problems with zero-one variables‎. ‎in this paper we formulate fully fuzzy linear programming problems with zero-one variables and a method for solving these problems is presented using the ranking function and also the branch and bound method along with an example is presented.

We present a suite of tools for visualizing the status and progress of branch-and-bound algorithms for mixed integer programming. By integrating these tools with the open-source codes CBC, SYMPHONY, and GLPK, we demonstrate the potential usefulness of visual representations in helping a user predict future progress of the algorithm or analyzing the algorithm’s performance. We have also implemen...