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Looks at modern electrochemical gas sensors: they way they work and the range of gases they can detect. The largest application area is in portable gas detection equipment where the emphasis is on small size and low power demands. These sensors are also used for emissions monitoring, specifically from combustion sources. Concludes that portable multigas detectors will continue to get smaller with a consequent reduction in size of sensors and that a wider range of gas sensors will be available with advances in electrochemistry.

Aims to focus on research and findings relating to the Z‐server response times and the performance of Z39.50 for parallel searching.

This paper begins by briefly outlining the evolution of Z39.50 and the current trends, including the work of the JISC CC‐interop project. The research crux of the paper focuses on an investigation conducted with respect to testing Z39.50 server (Z‐server) response times in a broadcast (parallel) searching environment. Customised software was configured to broadcast a search to all test Z‐servers once an hour, for 11 weeks. The results were logged for analysis.

Most Z‐servers responded rapidly. “Network congestion” and local online public catalogue usage were not found to influence Z‐server performance significantly. Response time issues encountered by implementers may be the result of non‐response by the Z‐server and how Z‐client software deals with this. The influence of “quick and dirty” Z39.50 implementations is also identified as a potential cause of slow broadcast searching.

The paper indicates various areas for further research, including setting shorter time‐outs and greater end‐user behavioural research to ascertain user requirements in this area. The influence more complex searches, such as Boolean, have on response times and suboptimal Z39.50 implementations are also emphasised for further study.

This paper informs the library and information science (LIS) research community and has practical implications for those establishing Z39.50 based distributed systems, as well as those in the web services community.

The paper challenges popular LIS opinion that Z39.50 is inherently sluggish and thus unsuitable for the demands of the modern user.

Detail research undertaken to determine the key differences in the performance of certain centralised (physical) and distributed (virtual) bibliographic catalogue services, and to suggest strategies for improving interoperability and performance in, and between, physical and virtual models.

Methodically defined searches of a centralised catalogue service and selected distributed catalogues were conducted using the Z39.50 information retrieval protocol, allowing search types to be semantically defined. The methodology also entailed the use of two workshops comprising systems librarians and cataloguers to inform suggested strategies for improving performance and interoperability within both environments.

Technical interoperability was permitted easily between centralised and distributed models, however, the various individual configurations permitted only limited semantic interoperability. Significant prescription in cataloguing and indexing guidelines, greater participation in the program for collaborative cataloguing, consideration of future functional requirements for bibliographic records migration, and greater disclosure to end users are some of the suggested strategies to improve performance and semantic interoperability.

This paper not only informs the library and information science research community and union catalogue administrators, but also has numerous practical implications for those establishing distributed systems based on Z39.50 and search/retrieve web services as well as those establishing centralised systems.

The paper moves the discussion of Z39.50‐based systems away from anecdotal evidence and provides recommendations based on testing, and is intimately informed by the UK cataloguing and systems librarian community.

The accurate measurement of the position and orientation of a robot end‐effector is the most critical issue for calibrating of robotic devices. Calibration methods provide tools to improve the accuracy of robots without modification to the mechanical unit or its control architecture. However, such calibration techniques require a large number of measurements. Dynamic measurement of position and orientation not only provides a solution to this problem, it also establishes the foundation for development of techniques to improve the robot’s dynamic accuracy. The concept of laser‐interferometry‐based measurement has been proposed. A system based on this concept is generally referred to as a laser tracking system (LTS). This paper describes the principle of laser‐interferometry‐based tracking. Further, the structure and various components within such a system are presented. A kinematic model for laser tracking is described and the performance of the system in its present configuration is presented. The application potential of such an approach to position and orientation (pose) measurement is also briefly described.

Laser interferometry‐based sensing (LIS) technique has been proposed and established recently to track and perform dynamic measurements on a moving end‐effector of a robot manipulator. In this paper, a technique using LIS system to perform guidance of a manipulator is proposed. The LIS system is used as a sensor to guide the end‐effector of a robot manipulator. This is to be accomplished through the implementation of guidance error determination and compensation, and path generation in the control algorithm. This technique can be used to accurately guide the manipulator’s end‐effector to a specified location or along a specified path with a high level of accuracy. The structure and various components within the system and the control strategy are also presented.

To explore the use of middleware to provide access to a virtual catalogue via Z39.50, allowing its integration with other services. To consider issues arising from the cross‐database search process and the problem of interoperability between systems.

Middleware was used to establish a Z39.50 server for an existing virtual union catalogue, InforM25. The Copac physical union catalogue was used to carry out cross‐database search tests, investigating the value of query transformation by the middleware and illustrating many of the issues associated with interoperability in cross‐database searching.

The test results demonstrate the viability and benefits of using middleware to allow the integration of virtual catalogues with other services. The results also illustrate the range of issues affecting the performance of the virtual catalogue, with supporting evidence from the use of the Copac physical union catalogue for cross‐database searching via Z39.50. In particular the discussion highlights the issue of semantic interoperability, as well as emphasising the value of centralised virtual catalogue support.

The research was limited to work on a specific virtual union catalogue, that is InforM25, but the results highlight issues with general relevance in the development of any virtual catalogue. The need for more work on response times in the virtual union catalogue is apparent, along with the related issue of result set post processing.

This paper provides a practical demonstration of the issues important to those involved in making their local catalogue accessible to services, and individuals, outside their own institution, as well as those working on virtual union catalogue development.

The purpose of this paper is to describe how, in the recent attempts to stimulate alternative energy sources for heating and cooling of buildings, emphasis has been put on utilisation of the ambient energy from ground source heat pump systems (GSHPs) and other renewable energy sources.

Exploitation of renewable energy sources and particularly ground heat in buildings can significantly contribute towards reducing dependency on fossil fuels. This paper highlights the potential energy saving that could be achieved through use of ground energy source. It also focuses on the optimisation and improvement of the operation conditions of the heat cycles and performances of the direct expansion (DX) GSHP.

It is concluded that the direct expansion of GSHP are extendable to more comprehensive applications combined with the ground heat exchanger in foundation piles and the seasonal thermal energy storage from solar thermal collectors.

The paper highlights the energy problem and the possible saving that can be achieved through the use of the GSHP systems and discusses the principle of the ground source energy, varieties of GSHPs, and various developments.

This study aims to examine the effectiveness of an integrated intervention program for alcoholism (IIPA) for improving verbal encoding and memory, visuospatial construction, visual memory and quality of life (QoL) in persons with alcohol dependence.

The sample comprised treatment-seeking alcohol-dependent persons (n = 50), allotted into two groups: (1) the treatment as usual (TAU) group (n = 25) and (2) the treatment group (n = 25)]. The groups were matched on age (±1 year) and education (±1 year). The TAU group received standard pharmacological treatment, psychotherapeutic sessions on relapse prevention and yoga for 18 days, while the treatment group received IIPA sessions in addition to the usual treatment. Auditory verbal learning test, complex figure test and QoL scale were administered at pre- and post-treatment along with screening measures.

The two groups were comparable on demographic variables, clinical characteristics and outcome measures at baseline. Pre- to post-treatment changes (gain scores) comparison between the treatment and TAU groups revealed a significant difference in verbal encoding, verbal and visual memory, verbal recognition, visuospatial construction and QoL.

This study suggests that IIPA is effective for improving learning and memory in both modality (verbal and visual) and QoL in persons with alcoholism. The IIPA may help in better treatment recovery.

The IIPA may help in treatment for alcoholism and may enhance treatment efficacy.

IIPA is effective for improving learning and memory in both modalities and QoL in persons with alcohol dependence. The IIPA may help in better treatment recovery.

Are there smart ways to find heuristics? What are the common principles behind heuristics? We propose an integrative definition of heuristics, based on insights that apply to all heuristics, and put forward meta-heuristics for discovering heuristics.

We employ Herbert Simon’s metaphor that human behavior is shaped by the scissors of the mind and its environment. We present heuristics from different domains and multiple sources, including scholarly literature, practitioner-reports and ancient texts.

Heuristics are simple, actionable principles for behavior that can take different forms, including that of computational algorithms and qualitative rules-of-thumb, cast into proverbs or folk-wisdom. We introduce heuristics for tasks ranging from management to writing and warfare. We report 13 meta-heuristics for discovering new heuristics and identify four principles behind them and all other heuristics: Those principles concern the (1) plurality, (2) correspondence, (3) connectedness of heuristics and environments and (4) the interdisciplinary nature of the scissors’ blades with respect to research fields and methodology.

We take a fresh look at Simon’s scissors-metaphor and employ it to derive an integrative perspective that includes a study of meta-heuristics.