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To develop a wireless sensor micro‐systems containing all the components of data acquisition system, such as sensors, signal‐conditioning circuits, analog‐digital converter, embedded microcontroller unit (MCU), and RF communication modules. This has now become the focus of attention in many biomedical applications.

The system prototype consists of miniature FSK transceiver integrated with MCU in one small package, chip antenna, and capacitive interface circuitry based on Delta‐sigma modulator. At the base station side, an FSK receiver/transmitter is connected to another MCU unit, which send the received data or received instructions from a PC through a graphical user interface GUI. Industrial, scientific and medical band RF (433 MHz) was used to achieve half duplex communication between the two sides. A digital filtering has been used in the capacitive interface to reduce noise effects forming capacitance to digital converter. All the modules of the mixed signal system are integrated in a printed circuit board of size 22.46 × 20.168 mm.

An innovation circuits and system techniques for building advanced smart medical devices have been discussed. Low‐power consumption and high reliability are among the main criteria that must be given priority when designing such wirelessly powered microsystems. Switched capacitors readout circuits have been found to be suitable for pressure sensing low‐power applications.

The presented wireless prototype needs a second phase of development that will lead to a further reduction in both size and power consumption. Currently, the main limitation of the RF system is the number of working hours according to the selected battery.

The developed system was found to be useful in terms of measuring pressure and temperature in a system of either slow or fast physical change. It would be a good idea to explore the system performance in human or animal trials.

This paper fulfils useful information for capacitive interface circuitries and presents a new short‐range wireless system that has different design features.

The development of a sensor microsystems containing all the components of data acquisition system, such as sensors, signal‐conditioning circuits, analog‐digital converter, interface circuits and embedded microcontroller (MCU), has become the focus of attention in many biomedical applications. A review of the microsystems technology is presented in this paper, along with a discussion of the recent trends and challenges associated with its developments. A basic description of each sub‐system is also given. This includes the different front end, mixed analog‐digital, power management, and radio transmitter‐receiver circuits. These sub‐system designs are presented and discussed in a comparative study and final remarks are made. The performance of each sub‐system is assessed regarding many aspects related to the overall system performance.

Telemetry capsules have existed since the 1950s and were used to measure temperature, pH or pressure inside the gastrointestinal (GI) tract. It was hoped that these capsules would replace invasive techniques in the diagnosis of function disorders in the GI tract. However, problems such as signal loss and uncertainty of the pills position limited their use in a clinical setting. In this paper, a review of the capabilities of microelectromechanical systems (MEMS) for the fabrication of a wireless pressure sensor microsystem is presented.

The circuit requirements and methods of data transfer are examined. The available fabrication methods for MEMS sensors are also discussed and examples of wireless sensors are given. Finally, the drawbacks of using this technology are examined.

MEMS for use in wireless monitoring of pressure in the GI tract have been investigated. It has been shown that capacitive pressure sensors are particularly suitable for this purpose. Sensors fabricated for wireless continuous monitoring of pressure have been reviewed. Great progress, especially using surface micromachining, has been made in recent years. However, despite these advances, some challenges remain.

Provides a review of the capabilities of MEMS.

The paper looks at the JAFER Toolkit Project.

The paper describes the JAFER toolkit for developing Z39.50 clients and servers using XML and XSLT and investigates how it might be used.

It has already been used on a number of projects and is being migrated to open source to enable further collaborative development by its users.

The paper is useful for those wishing or planning to use the JAFER Toolkit.

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.

This work aims to improve upon the linearity of integrated CMOS current sensors used in switch mode power supply topologies, using a low-cost and low-voltage (less than 1.2 V) CMOS technology node. Improved sensor accuracy contributes to efficiency in switched supplies by reducing measurement errors when it is integrated with closed-loop control.

Integrated current-sensing methods were investigated and CMOS solutions were prioritized. These solutions were implemented and characterized in the desired process and shortcomings were identified. A theoretical analysis accompanied by simulated tests was used to refine improvements which were prototyped. The current sensor prototypes were fabricated and tested.

Measured and simulated results are presented which show improved linearity in current sensor outputs. Techniques borrowed from analog amplifier design can be used to improve the dynamic range and linearity of current-steered CMOS pairs for measuring current. A current sensor with a gain of 5 V/A operating in a 10 MHz switch mode supply environment is demonstrated.

This paper proposes an alternative approach to creating suitable bias conditions for linearity in a SenseFET topology. The proposed method is compact and architecturally simple in comparison to other techniques.

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.

Considering its vast utility in industries, this paper aims to present a detailed review on fundamentals, classification and progresses in pressure sensors, along with its wide area of applications, its design aspects and challenges, to provide state-of-the-art gist to the researchers of the similar domain at one place.

Swiftly emerging research prospects in the micro-electro-mechanical system (MEMS) enable to build complex and sophisticated micro-structures on a substrate containing moving masses, cantilevers, flexures, levers, linkages, dampers, gears, detectors, actuators and many more on a single chip. One of the MEMS initial products that emerged into the micro-system technology is MEMS pressure sensor. Because of their high performance, low cost and compact in size, these sensors are extensively being adopted in numerous applications, namely, aerospace, automobile and bio-medical domain, etc. These application requirements drive and impose tremendous conditions on sensor design to overcome the tedious design and fabrication procedure before its reality. MEMS-based pressure sensors enable a wide range of pressure measurement as per the application requirements.

The paper provides a detailed review on fundamentals, classification and progresses in pressure sensors, along with its wide area of applications, its design aspects and challenges, to provide state of the art gist to the researchers of the similar domain at one place.

The present paper discusses the basics of MEMS pressure sensors, their working principles, different design aspects, classification, type of sensing diaphragm used and illustration of various transduction mechanisms. Moreover, this paper presents a comprehensive review on present trend of research on MEMS-based pressure sensors, its applications and the research gap observed till date along with the scope for future work, which has not been discussed in earlier reviews.

This review aims to give an overview about zinc oxide (ZnO) based gas sensors and the role of doping in enhancing the gas sensing properties. Gas sensors based on ZnO thin film are preferred for sensing applications because of their modifiable surface morphology, very large surface-to-volume ratio and superior stability due to better crystallinity. The gas detection mechanism involves surface reaction, in which the adsorption of gas molecules on the ZnO thin film affects its conductivity and reduces its electrical properties. One way to enhance the gas sensing properties is by doping ZnO with other elements. A few of the common and previously used dopants include tin (Sn), nickel (Ni) and gallium (Ga).

In this brief review, previous works on doped-ZnO formaldehyde sensing devices are presented and discussed.

Most devices provided good sensing performance with low detection limits. The reported operating temperatures were within the range of 200̊C –400̊C. The performance of the gas sensors can be improved by modifying their nanostructures and/or adding dopants.

As of yet, a specific review on formaldehyde gas sensors based on ZnO metal semiconductors has not been done.

Seeks to assess how new research and progress about how libraries and institutional web sites can adapt a range of distinct search tools using the portlet standards to achieve improved access.

Locally integrated web search tools help users to navigate through web sites without needing to go to multiple sites.

Search tools should be created with delivery via a portlet in mind. Compliance to CREE defined standards suggest good results as proven by several partners. This set of procedures suggests a very good future for locally integrated web search tools.

Examples of experiences with different partners suggest rather remarkable promise for portlet standards that can be applied to searching web sites The CREE project has proven easy adapability and now a significant amount of testing and experience confirms the operations it can perform with the JSR 168 and WSRP portlet standards and other Java‐based tools.