Path Relaxation is a method of planning safe paths around obstacles for mobile robots. It works in two steps: a global grid starch that finds a rough path, followed by a local relaxation step that adjusts each node on the path to lower the overall path cost. The representation used by Path Relaxation allows an explicit tradeoff among length of path, clearance away from obstacles, and distance t...

Computing cost optimal paths in network data is a very important task in many application areas like transportation networks, computer networks or social graphs. In many cases, the cost of an edge can be described by various cost criteria. For example, in a road network possible cost criteria are distance, time, ascent, energy consumption or toll fees. In such a multicriteria network, a route o...

The problem of determining an optimal path of a moving vehicle, considered in Sherali and Kim (1992), is studied in this paper. We generalize their model by including a general cost structure in the problem and show that a specific, non-trivial cost function in this setting yields an easy solution. This follows from the observation that the variational problem that arises in the model with this...

Communication networks have to provide a high level of resilience in order to ensure sufficient Quality of Service for mission-critical services. Currently, dedicated 1+1 path protection is implemented in backbone networks to provide the necessary resilience. On the other hand, there are several possible realization strategies for 1+1 path protection functionality (1PPF), utilizing both diversi...

Calculating the least-cost path (LCP) is a fundamental operation in raster-based geographic information systems (GIS). The LCP applied to raster cost surfaces, which it determines most cost-effective path. Increasing resolution results longer computation time obtain LCP. This paper proposes method for calculating using multi-resolution surface model enhance computational performance large-scale...

A methodology is presented for integrating effective-bandwidth-based routing for QoS-sensitive traffic and datagram routing of the best-effort traffic. To prevent excessive delays of best-effort traffic in a network domain, we develop (1) a constraint, stated in the form of a residual link bandwidth, and (2) a cost function for application to routing of QoS connections. Link-based and path-base...

In this paper, we study the minimum-cost quality-ofservice multicast and unicast routing problems in communication networks. For the multicast problem, we present an efficient approximation algorithm to find a balance between a minimum-cost multicast tree and a minimum-delay multicast tree, with a provably good performance under the condition that link delay and link cost are identical. For the...

We show that the following variation of the single-source shortest path problem is NP-complete. Let a weighted, directed, acyclic graph G = (V, E, w) with source and sink vertices s and t be given. Let in addition a mapping f on E be given that associate information with the edges (e.g., a pointer), such that f (e) = f (e ′) means that edges e and e ′ carry the same information; for such edges ...