Derivative-free algorithms are frequently required for the optimization of nonsmooth scalar functions in n dimensions resulting, for example, from physical experiments or from the statistical averaging of numerical simulations of chaotic systems such as turbulent flows. The core idea of all efficient algorithms for problems of this type is to keep function evaluations far apart until convergenc...

In this paper, we compare two approaches for exploring large, hierarchical data spaces of social media data on mobile devices using facets. While the first approach arranges the facets in a 3x3 grid, the second approach makes use of a scrollable list of facets for exploring the data. We have conducted a between-group experiment of the two approaches with 24 subjects (20 male, 4 female) executin...

The convergence of direct search methods for unconstrained minimization is examined in the case where the underlying method can be interpreted as a grid or pattern search over successively refined meshes. An important aspect of the main convergence result is that translation, rotation, scaling and shearing of the successive grids are allowed.

EGSO is part of the Virtual Solar Observatory. It provides a Grid for integrated access to distributed and heterogeneous solar data archives. Here we describe the motivation and approach we have chosen to implement the Grid access as a stateful web service. Using this kind of service allows us to consider the search and retrieval of data as an interaction between the client and the Grid. This w...

A typical AEC industry project involves many individuals and companies forming a consortium for the duration of a project. These projects are usually unique, very complex and involve many participants from a number of organizations acting collaboratively, and forming Virtual Organisations to enable this collaboration. This document is intended to describe the complete design and implementation ...

In this paper, we analyze some technical issues concerning the use of Grid-enabled technologies based on the Globus Toolkit to solve multi-objective optimization problems. We develop two distributed algorithms: an enumerative search and an evolutionary algorithm. The former is a simple technique, whose high time complexity is mastered down to acceptable execution times to some extent by the use...

Grid-based path finding is required in many games to move agents. We present an algorithm called DBA* that uses a database of pre-computed paths to reduce the time to solve search problems. When evaluated using benchmark maps from Dragon Age, DBA* requires less time for search and produces less suboptimal paths than the PRA* implementation used in Dragon Age.

The process of design search and optimisation is characterised by its computationally intensive operations, which produce a problem well suited to Grid computing. Here we present a Grid enabled computation toolkit that provides transparent and stable access to Grid compute resources from Matlab, which offers comprehensive support for the design optimisation processes. In particular, the access ...

We investigate the problem of supporting keyword-based searching for the discovery of software resources that are installed on the nodes of large-scale, federated Grid computing infrastructures. We address a number of challenges that arise from the unstructured nature of software and the unavailability of software-related metadata on Grid sites. We present Minersoft, a Grid harvester that visit...