Across the bridge: CLEF 2001 - Non-English monolingual retrieval. The French task.

This paper presents work on document retrieval based on first time participation in the CLEF 2001 monolingual retrieval task using French. The experiment findings indicated that Okapi, the text retrieval system in use, can successfully be used for non-English text retrieval. A lot of internal pre-processing is required in the basic search system for conversion into Okapi access formats. Various shell scripts were written to achieve the conversion in a UNIX environment, failure of which would significantly have impeded the overall performance. Based on the experiment findings using Okapi - originally designed for English - it was clear that, although most European languages share conventional word boundaries and variant word morphemes formed by the additon of suffixes, there is significant difference between French and English retrieval depending on the adaptation of indexing and search strategies in use. No sophisticated method for higher recall and precision such as stemming techniques, phrase translation or de-compounding was employed for the experiment and our results were suggestively poor. Future participation would include more refined query translation tools.

Flexible self-adjustment of task deployment in dynamic environments

This paper presents an investigation into dynamic self-adjustment of task deployment and other aspects of self-management, through the embedding of multiple policies. Non-dedicated loosely-coupled computing environments, such as clusters and grids are increasingly popular platforms for parallel processing. These abundant systems are highly dynamic environments in which many sources of variability affect the run-time efficiency of tasks. The dynamism is exacerbated by the incorporation of mobile devices and wireless communication. This paper proposes an adaptive strategy for the flexible run-time deployment of tasks; to continuously maintain efficiency despite the environmental variability. The strategy centres on policy-based scheduling which is informed by contextual and environmental inputs such as variance in the round-trip communication time between a client and its workers and the effective processing performance of each worker. A self-management framework has been implemented for evaluation purposes. The framework integrates several policy-controlled, adaptive services with the application code, enabling the run-time behaviour to be adapted to contextual and environmental conditions. Using this framework, an exemplar self-managing parallel application is implemented and used to investigate the extent of the benefits of the strategy

Solid phase velocity measurements utilising electrostatic sensors and cross correlation signal processing

Gas-solids two phase systems are widely employed within process plant in the form of pneumatic conveyors, dust extraction systems and solid fuel injection systems. The measurement of solids phase velocity therefore has wide potential application in flow monitoring and, in conjunction with density measurement instrumentation, solids mass flow rate measurement. Historically, a number of authors have detailed possible measurement techniques, and some have published limited test results. It is, however, apparent that none of these technologies have found wide application in industry. Solids phase velocity measurements were undertaken using real time cross correlation of signals from two electrostatic sensors spaced axially along a pipeline conveying pulverised coal (PF). Details of the measurement equipment, the pilot scale test rig and the test results are presented.