Antonio J. Fernández

Learn More
This paper describes a proposal to incorporate nite domain constraints in a functional logic system. The proposal integrates functions, higher-order patterns, partial applications, non-determinism, logical variables, currying, types, lazyness, domain variables, constraints and nite domain propagators. The paper also presents TOY(FD), an extension of the(More)
Branch-and-bound (BnB) and memetic algorithms represent two very different approaches for tackling combinatorial optimization problems. However, these approaches are compatible. In this correspondence, a hybrid model that combines these two techniques is considered. To be precise, it is based on the interleaved execution of both approaches. Since the(More)
We consider the problem of finding small Golomb rulers, a hard combinatorial optimization task. This problem is here tackled by means of a hybrid evolutionary algorithm (EA). This EA incorporates ideas from greedy randomized adaptive search procedures (GRASP) in order to perform the genotype-to-phenotype mapping. As it will be shown, this hybrid approach(More)
This paper deals with the construction of binary sequences with low autocorrelation, a very hard problem with many practical applications. The paper analyzes several metaheuristic approaches to tackle this kind of sequences. More specifically, the paper provides an analysis of different local search strategies, used as standalone techniques and embedded(More)
In this paper, we present our proposal to Constraint Functional Logic Programming over Finite Domains (CFLP (FD) ) with a lazy functional logic programming language which seamlessly embodies finite domain (FD) constraints. This proposal increases the expressiveness and power of constraint logic programming over finite domains (CLP (FD) ) by combining(More)
PURPOSE To confirm the efficacy of a risk-adapted treatment approach for patients with clinical stage I seminoma. The aim was to reduce both the risk of relapse and the proportion of patients receiving adjuvant chemotherapy while maintaining a high cure rate. PATIENTS AND METHODS From 2004 to 2008, 227 patients were included after orchiectomy in a(More)
Zinc, Copper, Iron. Calcium Phosphorous and Magnesium contents were determined in early milk samples in 72 mothers from Caracas city. The samples were collected during three different lactation stages: calostro (3 days), transitional (7 days) and mature milk (21 days). The more significant changes in the concentration of the studied elements were observed(More)
The Golomb ruler problem is a very hard combinatorial optimization problem that has been tackled with many different approaches, such as constraint programming (CP), local search (LS), and evolutionary algorithms (EAs), among other techniques. This paper describes several local search-based hybrid algorithms to find optimal or near-optimal Golomb rulers.(More)
A hybridization of an evolutionary algorithm (EA) with the branch and bound method (B&B) is presented in this paper. Both techniques cooperate by exchanging information, namely lower bounds in the case of the EA, and partial promising solutions in the case of the B&B. The multidimensional knapsack problem has been chosen as a benchmark. To be precise, the(More)
Finding binary sequences with low auto correlation is a very hard problem with many practical applications. In this paper we analyze several meta heuristic approaches to tackle the construction of this kind of sequences. We focus on two different local search strategies, steepest descent local search (SDLS) and tabu search (TS), and their use both as(More)