the heterogeneous fixed fleet open vehicle routing problem (hffovrp) is one of the most significant extension problems of the open vehicle routing problem (ovrp). the hffovrp is the problem of designing collection routes to a number of predefined nodes by a fixed fleet number of vehicles with various capacities and related costs. in this problem, the vehicle doesn’t return to the depot after se...

This paper shows simple dynamic programming algorithms for RNA secondary structure prediction with pseudoknots. For a basic version of the problem (i.e., maximizing the number of base pairs), this paper presents an O(n) time exact algorithm and an O(n4− ) time approximation algorithm. The latter one outputs, for most RNA sequences, a secondary structure in which the number of base pairs is at l...

We give a comprehensive theoretical treatment for calculating the viewshed of a given point, present an analytical solution to the viewshed problem and a new algorithm for finding the viewshed on a triangulated terrain. We implement our algorithm on a real terrain. Some algorithms make use of the horizon information of the terrain to calculate viewshed. The vertices of the horizon of the terrai...

We show an alternative way of represent­ ing a Bayesian belief network by sensitivities and probability distributions. This represen­ tation is equivalent to the traditional rep­ resentation by conditional probabilities, but makes dependencies between nodes apparent and intuitively easy to understand. We also propose a QR matrix representation for the sensitivities and/ or conditional probabili...

In this work we study the Capacitated p-Center Problem (CpCP ) and we propose an exact algorithm to solve it. We study two auxiliary problems and their relation to CpCP , and we propose two different Lagrangean duals based on each of the auxiliary problems. The lower and upper bounds provided by each of the Lagrangean duals reduce notably the set of candidate radii and allow to solve the proble...

We present a heuristic matching algorithm for the generation of ground states of the short-range * J spin glass in two dimensions. It is much faster than previous heuristic algorithms. I t achieves near optimal solutions in time O( N ) in contrast to the best known exact algorithm which needs a time of O ( N S ” ) . From simulations with lattice sizes of up to 210 x 210 we confirm a phase trans...

This paper investigates two problems related to the determination of critical edges for the minimum cost assignment problem. Given a complete bipartite balanced graph with n vertices on each part and with costs on its edges, k Most Vital Edges Assignment consists of determining a set of k edges whose removal results in the largest increase in the cost of a minimum cost assignment. A dual proble...

One of the problems arising in the analysis of biological sequences is the discovery of sequence similarity by finding common motifs. Several versions of the motif finding problem have been proposed for dealing with this problem and for each version, numerous algorithms have been developed. In this paper, we propose an exact algorithm, called SMS-H-FORBID to solve the Simple Motif Problem (SMP)...

We consider the problem of packing a family of disks “on a shelf,” that is, such that each disk touches the x-axis from above and such that no two disks overlap. We prove that the problem of minimizing the distance between the leftmost point and the rightmost point of any disk is NP-hard. On the positive side, we show how to approximate this problem within a factor of 4/3 in O(n logn) time, and...