Supporting Information Step

The data requirements in the supporting information step differ greatly from those in the screening step. It is not necessary to screen all entities in the "kingdom", only to find necessary additional information about the few candidates that have already been identified by the screening step. Typically, it is desirable to check non-quantifiable information. For materials this may be information about the microstructure; details about joining characteristics; corrosion resistance in a specific environment; detailed information on availability and pricing; or exact property values for the particular version of the material made by one manufacturer. It is on this basis that the initial short list of candidates is narrowed down to one or a few prime choices.

Figure 1 The Supporting Information Step

Data format:

The supporting information system is likely to contain specialist information about a relatively narrow range of entities. The information may be in the form of text, tables, graphs, photographs, computer programs, even video clips (see for example [9]). There can be large quantities of data and it can be very detailed and of high precision. The most common medium for such data is manufacturers' leaflets and catalogues. However, increasingly, such information is becoming available electronically in the form of databases provided by manufacturers, on CD-ROMs or on the Internet (see figure 1).

Searching strategies:

Because the data is in "free" format, the available searching strategies are completely different to the numerical optimisation procedures that are needed during the screening step. However, since candidate entities have already been identified, it is only necessary for the supporting information system to provide a mechanism for accessing information about these known entities. The simplest approach is to use an index (as in a printed book); or a keyword list; or computerised full text search, as implemented in many hyper-media systems.

Example:

The Megabytes on Coppers CD-ROM [9], (produced by Granta Design Limited for the Copper Development Association—CDA) is an example of a further information system. It contains all of the information about copper alloys published by CDA, including books, brochures, leaflets and computer programs.
Megabytes on Coppers is a stand-alone multi-media system, which can also be linked to CES via material identifiers, which are unique keys for each material. In this configuration, CES is used to screen all classes of materials and narrow-down the choice to a few candidates. The identifier of a candidate material is then transmitted by CES to the CD-ROM's search engine, which automatically locates all supporting information about that material on the CD-ROM. This information can then be viewed on the screen, printed out and so on. It is also possible to search the CD-ROM using keywords, material identifiers or both, and to jump between pages of information using hot links. As an example, the search window of Megabytes on Coppers is shown in Figure 2.

Figure 2 Search window from the Megabytes on Coppers CD-ROM. It is possible to search on the basis of material identifier or keyword, in any combination

Data sources on the Internet:

The Internet contains an expanding spectrum of information sources. Some, particularly those on the Worldwide Web, contain data for materials. It can therefore be used as a useful source of supporting information, once a candidate material has been identified by a screening process. The information is provided by standards organisations; trade associations; learned societies; universities; and individual manufacturers or suppliers, who provide information about their specific product ranges. Table 1 contains details of a few Worldwide Web sites containing general information about iron and steel. They are examples of the websites concerned with materials, processes, suppliers and so on that are stored in the WebLinks search engine hosted on the Granta Design Website—all entries are handchecked and regularly updated.

Internet Address (URL)	Description of site
http://www.steelnet.org	Steel Manufacturers Association, North America"s largest steel trade group. Contains links to the home pages of many US steel companies.
http://www.asm-intl.org	ASM International (American Society of Materials). Linked to a wide range of useful sites.
http://www.astm.org	American Society of Testing and Materials, publisher of a wide range of American standards.
http://www.iso.ch	International Standards Organisation—has links to all national standards organisations that have a presence on the WWW.
http://www.iso.ch/cate/77.html	Section 77 of the ISO catalogue, which includes descriptions of all their standards on ferrous metals, plus ordering information.