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This final instalment covers present generation printers and includes a description of printer control languages, particularly Postscript, and colour printers. The concluding section is about the use of image processing in libraries as embodied in page preservation systems, facsimile—which has had a long chequered career—Desktop Publishing, with some examples of the kind of work being done in libraries, and Compact Discs.

Desktop publishing has emerged in the last few years as perhaps the most exciting new application of the microcomputer. Prior to this development, the only way of producing high quality printed output from computer generated text was to use elaborate embedded formatting codes for driving a typesetter (as in the Unix troff system) or else to use very expensive purpose built equipment (such as that developed for the newspaper printing industry). Thanks to desktop publishing the situation has changed dramatically. With the aid of software packages such as Ventura Publisher or Pagemaker, low cost microcomputers and laser printers can be used to produce high quality camera ready output in a great variety of formats and with sophisticated typographic control. With such cost savings, the quality of presentation material can be greatly improved. It becomes affordable for even small organisations to produce, in‐house, properly printed brochures, newsletters, factsheets, and other forms of documentation. This move towards a higher quality of published information helps immeasurably to improve the public image and credibility of the organisation. With greater control over the printing process it also becomes easier to provide more frequent updates of material. Thus information can be more timely and accurate, as well as better presented. In addition, it may no longer be necessary to print off large numbers of any particular document at any one time: short runs and ‘publication on demand’ become feasible with DTP. Even online storage and document delivery over communications networks become possible, particularly with the adoption of a standard page description language (such as PostScript). In summary, desktop publishing makes communication easier, both by making the printed product more readable and by enabling a whole range of additional services to be added; such as frequent updating, demand publishing and electronic archiving. New methods of document distribution, using electronic mail or other digital networks, also become possible. In this sense, it may represent just the first step towards a radical change in the way we communicate.

Introduces several new versions of PageRank (the link based Web page ranking algorithm), based on an information science perspective on the concept of the Web document. Although the Web page is the typical indivisible unit of information in search engine results and most Web information retrieval algorithms, other research has suggested that aggregating pages based on directories and domains gives promising alternatives, particularly when Web links are the object of study. The new algorithms introduced based on these alternatives were used to rank four sets of Web pages. The ranking results were compared with human subjects’ rankings. The results of the tests were somewhat inconclusive: the new approach worked well for the set that includes pages from different Web sites; however, it does not work well in ranking pages that are from the same site. It seems that the new algorithms may be effective for some tasks but not for others, especially when only low numbers of links are involved or the pages to be ranked are from the same site or directory.

Web impact factors, the proposed web equivalent of impact factors for journals, can be calculated by using search engines. It has been found that the results are problematic because of the variable coverage of search engines as well as their ability to give significantly different results over short periods of time. The fundamental problem is that although some search engines provide a functionality that is capable of being used for impact calculations, this is not their primary task and therefore they do not give guarantees as to performance in this respect. In this paper, a bespoke web crawler designed specifically for the calculation of reliable WIFs is presented. This crawler was used to calculate WIFs for a number of UK universities, and the results of these calculations are discussed. The principal findings were that with certain restrictions, WIFs can be calculated reliably, but do not correlate with accepted research rankings owing to the variety of material hosted on university servers. Changes to the calculations to improve the fit of the results to research rankings are proposed, but there are still inherent problems undermining the reliability of the calculation. These problems still apply if the WIF scores are taken on their own as indicators of the general impact of any area of the Internet, but with care would not apply to online journals.

This paper aims to provide a functional review of Greenstone based on selected criteria, viz., user friendliness, administration, customization, international metadata standards and interoperability, search and browse capabilities, security aspects, statistical reports, unique features and limitations.

The paper is solely based on secondary information collected from different sources like books, articles from national and international journal articles, reports of various organizations and local newspapers as well as the resources available in various websites.

It was observed that the Greenstone on Windows is less robust than the other operating systems such as Linux. It was reported that during the collection building process of some documents, the system hangs and the user has to turn off the browsers and the interfaces, and no alternate method is available to restore normalcy. The software has been reviewed on selected criteria, and it is suggested to use Greenstone Digital Library Management System (DLMS) system as the most suitable and convenient for installation, uploading of documents and usage for small- and medium-type organizations.

This paper would be of great help for library professionals to learn about diverse features available in the software and in selecting the best DLMS.

The Greenstone DLMS is functionally reviewed and analysed based on selected broad criteria, viz., user friendliness, administration, customization, international metadata standards and interoperability, search and browse capabilities, security aspects and statistical functions.

On the heels of the rapid growth of the World Wide Web have come advances in multimedia document formats and the hardware and software to support them. As a result of this combination of factors, the electronic journal is, at last, economically and aesthetically viable.

Standards exist for many aspects of scientific and technical information and its management. This paper examines standardization from the perspective of an ‘ideal information scenario’. It focuses both on the older well‐established standards and those standards currently under development which are most important for information management. It concludes with a proposed approach for planning standards activity.

Krakatoa explodes onto the Web. Anyone who has finally just about got the hang of hypertext markup language for designing pages on the World Wide Web could be excused for burying their heads in the sand and hoping the latest development, Java, will go away. It is highly unlikely that it will, since Java is to HTML what freshly ground beans are to a cheap brand of instant. With HTML alone a typical Web page consists of static text and graphics, but Java allows a more proactive element to creep in that makes it far more responsive to the user's desires and needs.

The CORE project is an electronic library prototype that provides networked access to the full text and graphics content of American Chemical Society journals and associated Chemical Abstracts Service indexing since 1980 (some 250 journal years of data). The database is coded in Standard Generalized Markup Language (translated from original typography codes) which captures the structural richness of the original document and provides flexibility for indexing, searching, and display. The prototype provides a full‐scale laboratory environment in which to explore issues of database structure, user interface capabilities, and information retrieval questions on a large, real‐world scholarly electronic journal database. The complete database, representing more than 600,000 pages of full text and graphics, will be the largest electronic corpus of its kind. Scheduled for availability at Cornell in late 1993, this database will be available for use by the Cornell Chemistry Department faculty and students on a local area network (although the architecture of the CORE system is extensible to wide area networks as well)

Non-uniform rational B-splines (NURBSs) are the de facto standard for representing objects in computer-aided design (CAD). The purpose of this paper is to discuss how to stick to this standard in all phases of the additive manufacturing (AM) workflow, from the CAD object to the final G-code, bypassing unnecessary polygonal approximations.

The authors use a commercial CAD system (Rhino3D along with its programming environment Grasshopper) for direct slicing of the model, offset generation and trimming. Circular arcs are represented as quadratic NURBSs and free-form geometry as quadratic or cubic polynomial B-splines. Therefore, circular arcs are directly expressible as G2/G3 G-code commands, whereas free-form paths are rewritten as a succession of cubic Bézier curves, thereby admitting exact translation into G5 commands, available in firmware for AM controllers, such as Marlin.

Experimental results of this paper confirm a considerable improvement in quality over the standard AM workflow, consisting of an initial polygonization of the object (e.g. via standard tessellation language), slicing this polygonal approximation, offsetting the polygonal sections and, finally, generating G-code made up of polyline trajectories (G1 commands).

A streamlined AM workflow is obtained, with a seamless transfer from the initial CAD description to the final G-code. By adhering to the NURBS standard at all steps, the authors avoid multiple representations and associated errors resulting from approximations.