Machine-Readable Representations

The system presented here is just good for labeling botdes containing basic chemicals in the laboratory. The advantage is that the names that are generated are pronounceable, in contrast to those generated as machine-readable notations. Actually, this system was developed and used by the author during his temporary research time in industry. 

From Table 14.3, we can easily generate some examples for this nomenclature system. In Table 14.4 we give a few examples for this type of nomenclature. Of course, this nomenclature is applicable only to basic organic chemicals with a comparatively simple structure. 

With the advent of chemical drawing programs, many file formats have been developed. The majority of these file formats show how to plot a chemical structure and its bonds, by storing certain internal coordinates needed for plotting. On the other 

These notation systems are loosing importance for the ordinary user, as computer programs can read now structures that are drawn on the screen. However, in contrast, structures can be drawn via such notation systems conveniently on the screen and as output in chemical drawing programs. These forms of representation are the base of molecular modeling. 

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A bar code is a computer or machine-readable representation of information. It is usually made of dark ink on a light background to create high and low reflectance which is converted to Is and Os, when read by the computer program. A similar result may be achieved by patterns of dots, concentric circles, or text codes hidden within images. A bar code containing stored data in the widths and spacings of printed parallel lines or other patterns as... 

GORE. The CORE Electronic Chemistry Library is a joint project of Cornell University, OCLC (On-line Computer Library Center), Bell Communications Research (Bellcore), and the American Chemical Society. The CORE database will contain the full text of American Chemical Society Journals from 1980, associated information from Chemical Abstracts Service, and selected reference texts. It will provide machine-readable text that can be searched and displayed, graphical representations of equations and figures, and full-page document images. The project will examine the performance obtained by the use of a traditional printed index as compared with a hypertext system (SUPERBOOK) and a document retrieval system (Pixlook) (6,116). 

Four main approaches have been suggested for the representation of chemical structures in machine-readable form fragment codes, systematic nomenclature, linear notations, and connection tables. 

Fig. 9.6 Human versus machine-readable chemical structure representations. Names based on the depicted structures were interpreted using ACDName [22]. The cross up/down wedge error (middle) causes errors in assigning the absolute chirality.

A special attention is given to stereochemistry, as some compounds are published without proper chirality representation even though the information is available, for example, for natural compounds and their derivatives. Furthermore, as illustrated in Fig. 13.2-8, compounds published in medicinal chemistry literature are often depicted in a human-readable format that is, structures are drawn in a format that chemists can interpret to reconstruct proper chirality. However, this format is not machine-readable , that is, cheminformatics software for 3D structural conversion, or for automatically generating IUPAC (International Union of Pure and Applied Chemistry) nomenclature, cannot perceive the stereo centers correctly... 

A barcode basically is a machine-readable visual representation of information printed on the surface of objects. There are several different kinds of barcodes, for example, barcodes which store data in the widths and spacing of printed parallel lines, and those that store data within the patterns of dots, or concentric circles, or even hidden within images. This encoded data on the barcodes is read by barcode readers, which update the backend ERP, SCM, or WMS systems. However there are some inherent issues with using a barcode, for instance, barcodes become ineffective in rain, fog, snow, dirt and grime, and so forth (Tecstra, n.d.). Since barcodes rely on optical sensors, any minor change on the barcode print can make it difficult to read. This can be commonly seen at point of sale (POS) in the supermarkets, where the POS operator scans the barcode several times because it is either wet or not aligned properly. 

Transformation of the conceptual model into an implemented one involves the transformation of ontological representations into formal machine-readable specifications using ontology representation language. For this purpose, selection of a... 

Underpinning all the other activities in the SSI TOOLS project is the need to have a machine-readable description of the railway layout to be signalled. A prime requirement for any such description is the need to elaborate it later, for instance as additional functions such as Automatic Train Protection are required. A number of alternative representations were considered for this task, including ... 

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