Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

OPS (Organic Prestressing System) - nowa technologia w budownictwie mostowym

Pacheco P., Guerra A., Borges P., Coelho H., Campos R.

Inżynieria i Budownictwo

2007

R. 63, nr 10

520-523

Opisano badania nad organicznym systemem sprężania (OPS) oraz jego rozwój i zastosowania. Przedstawiono etapy analizy numerycznej i eksperymentalnej oraz pierwsze zastosowanie konstrukcji dźwigara przesuwnego o naturalnej wielkości, wzmocnionego systemem OPS. Podsumowanie zawiera krótki opis innych zastosowań OPS oraz wnioski.

An overview of organic prestressing system (OPS) research, development and application project is presented. After the main concept presentation, highlights of numerical and experimental analysis research stages are pointed out. The first full scale application of a launching gantry strengthened with OPS is synthetically described and the constructor's perspective is presented. Finally, other OPS applications are shortly mentioned and conclusions are established.

Fixed channel assignment in cellular communication systems considering the whole set of packed patterns. An investigation based on metaheuristics

Borges P., Vidal R.

Control and Cybernetics

2000

Vol. 29, no 3

685-700

This paper addresses the problem of fixed channel assignment in cellular communication systems with nonuniform traffic distribution. The objective of the channel assignment is to minimise the average blocking probability. Methods for finding a good allocation can be based on first building a number of sets of cochannel cells or allocation patterns and then assigning them to channels. This usually implies that only a subset of the feasible region is attainable. The approach suggested in this paper uses the concept of packed pattern, since all patterns in an optimal solution will be of that kind. With a constructive method, the entire set of packed patterns is built and used in the optimisation process. The complexity (large-scale and nonlinearity) of the resulting problem suggested the use of general search procedures (local search, tabu search, simulated annealing, etc.), which have the further advantage of flexibility when dealing with extensions to the problem. A neighbouring structure was used, that facilitated the calculations while still allowing for the search in the entire solution space. A summary of extensive numerical experiments is presented. The outcome is an improvement over previous results.