Documentation systems in Britain’s National Art Library

Britain’s National Art Library at the Victoria & Albert Museum joined the OCLC network in 1986, and from 1987 to 1990 created catalogue records in MARC format on the OCLC database pending the introduction of a stand-alone computer system. The Library now employs a Dynix minicomputer system for cataloguing, acquisitions, circulation, serials control, and the provisions of OPACs. About 15% of the Library’s records are available online. Retrospective conversion of older records is proceeding and may be completed by the year 2000. The online catalogue is networked internally within the Museum, and is likely to be accessible to external users via JANET in the future. A number of bibliographic and image databases are also provided in CD-ROM and videodisc format. Future developments will include interface between Museum/image and Library/documentation databases.

A metrology electron microscope system

An electron microscope system has been constructed which is capable of calibration-quality dimensional measurements from 0.5 to 150 μm. This system was designed to certify one dimensional calibration artifacts for micrometrology instruments. Examples of these artifacts include stage micrometers for microscope magnification calibration and polystyrene latex for flow-through particle sizing instrumentation.The principle of operation of the instrument is similar to that of an ordinary optical measuring microscope. The electron beam is fixed in position and acts as the reference point. The measured object is translated beneath the electron beam on an electromechanically scanned stage. The displacement of the stage is determined by a commercial optical intei— ferometric measurement system. Therefore the metric of the system is directly traceable to the wavelength standard. One of the electron output signals from the specimen is stored synchronously with the data output from the interferometer by a dedicated minicomputer system. Subsequent analysis of the electron intensity profile is used to determine the measured size of the object.