Edie M. Rasmussen

Searching and clustering of databases using the ICL Distributed Array Processor

Abstract The ICL Distributed Array Processor (DAP) is an SIMD array processor containing a large, 2-D array of bit serial processing elements. The architecture of the DAP makes it well suited to data processing applications where searching operations must be carried out on large numbers of data records. This paper discusses the use of the DAP for two such applications, these being the scanning of serial text files and the clustering of a range of types of database. The processing efficiency of the DAP, when compared with a serial processor, is greatest when fixed length records are processed.

Non-hierarchical document clustering using the ICL distribution array processor

This paper considers the suitability and efficiency of a highly parallel computer, the ICL Distributed Array Processor (DAP), for document clustering. Algorithms are described for the implementation of the single-pass and reallocation clustering methods on the DAP and on a conventional mainframe computer. These methods are used to classify the Cranfield, Vaswani and UKCIS document test collections. The results suggest that the parallel architecture of the DAP is not well suited to the variable-length records which characterise bibliographic data.

Searching of chemical structure data bases with parallel computer hardware

Abstract The use of two types of parallel computer hardware for increasing the efficiency of processing in chemical structure data bases is discussed. The distributed array processor can be used for the clustering of 2-D chemical structure data bases by using the Jarvis—Patrick clustering method and for the ranking of output in an experimental system for substructure searching in the 3-D macromolecules in the Protein Data Bank. The Inmos transputer can be used in the construction of PC-based systems for 2-D substructure searching and in the identification of the maximal substructures common to pairs of 3-D molecules.

Chemical Structure Handling Using the Distributed Array Processor

The Distributed Array Processor (DAP) is a parallel computer that allows the simultaneous processing of many thousands of data items. The massively parallel nature of the DAP is well suited to the processing of large databases and in this paper we describe its use for the clustering of files of 2-D structures using the Jarvis-Patrick clustering method, for the ranking of output in an experimental substructure searching system for the 3-D macromolecules in the Protein Data Bank, and for the implementation of atom-by-atom searching using Ullmann’s subgraph isomorphism algorithm. The experimental results demonstrate that the DAP is considerably faster than a conventional mainframe processor, although the precise degree of speed-up that can be obtained is strongly dependent upon the characteristics of the data that is to be processed.

Processing of chemical structure databases using parallel computer hardware

This paper summarises recent work at Sheffield University on the use of parallel computer hardware for the processing of chemical structure databases. The Distributed Array Processor, or DAP, has been used for the clustering of the fragment bit strings representing 2-D molecules (for chemical structure-property applications) and the ranking of output in an experimental system for substructure searching of the macromolecules in the Protein Data Bank. The Inmos Transputer has been shown to provide a highly cost-effective way of increasing the efficiency of searching in microcomputer-based substructure searching systems.

The EurolEMasters project: a European Masters degree in Information Engineering

The European Commission funds a number of technically-based research and development programs such as ESPRIT and the Telematics Applications Programme (TAP). Information Engineering (IE) is one of the areas which receives part-funding for research and development through TAP. This sector essentially covers techniques to provide access to electronic information in all its forms based upon the notion of the information chain and including the areas of electronic publishing, information dissemination and information retrieval.