Information System,

The authors thank the german research community (DFG) for the support of the presented investigations whieh were realized inside the Special Research Area 326, named, J rocess Integrated Quality Control with Quality Information System for Metallic Parts in Mechanical Engineering, and special thanks to the scientific bilateral project between Brazil and Germany supported by the CNPq, KFA and DLR to realize the presented investigations in advanced radioscopy and tomography. 

Almost all chemical information systems work with tlicir own special type of connection table. They often use various formats distinguishing between internal and external connection tables. In most cases, the internal connection tables arc redundant, thus allowing maximum flexibility and increasing the speed of data processing. The external connection tables are usually non-redundant in order to save disk space. Although a connection table can be cprcsented in many different ways, the core remains the same the list of atoms and the list of bonds. Thus, the conversion of one connection table format into another is usually a fairly straightforward task. 

Parallel to that the MDL Molfile format (see the Tutorial in Section 2.4.6) developed at Molecular Design Limited (now MDL Information Systems, Inc.) became a de facto standard file format [50]. 

D. Bawden, E.M. Mitchell, Chemical Information Systems - Beyond the Structure Diagram, Elhs Horwood, Chichester, UK, 1990. 

Ctfile Formats, MDL Information Systems, CA, USA, 1998 http //urww.mdli.com/ downloads/ctftle/cftle subs.html... 

J.M. Barnard, C.J. Jochum, S.M. Wel-ford, ROSDAL A universal structure/ substmcture representation for PC-host communication, in Chemical Structure Information Systems Interfaces Communication and Standards, WA. Warr (Ed.), ACS Symposium Series No. 400, American Chemical Sodety, Washington, DC, 1989, pp. 76- 81. 

C.K. Johnson, ONRL Report No. 3794, Oak Ridge National Laboratory, Oak Ridge, TN, 1965 abstract available at http //www.umass.edu/molvis/fran-coeur/ortep/ortepabstract.html [5 Ctfile Formats, MDL Information Systems, CA, 1998 http //www.mdli.com/ downloads... 

P. Willett, Similarity and Clustering in Chemical Information Systems, Research Studies Press, Letchworth, UK. 1986. 

Sf The Chemlnjbrm RX reaction database is produced by FIZ Chemie, Berlin, Germany, and marketed by MDL Information Systems, Inc., San Leandro, CA, USA. 

There are basieally two different approaches in an information system for providing information with a database (sec Figures 5-1 and 5 2),... 

More than 10 000 databases exist that provide a small or large amount of data on various topics (including chemistry). The contents in databases are supplied by approximately 3500 database developers (e.g., the Chemical Abstracts Service, MDL Information Systems, etc.). Since there is a variety of topics from economics to science, as well as a variety of structures of the database, only some of the vendors (-2000) offer one or more databases as either local or as online databases (Figure 5-4) [4]. Usually, databases are provided by hosts that permit direct access to more than one database. The search occurs primarily through different individual soft-... 

The database is produced by the German Chemical Society (GDCh) and provided by MDL Information Systems Inc. [22]. 

Specinfo, from Chemical Concepts, is a factual database information system for spectroscopic data with more than 660000 digital spectra of 150000 associated structures [24], The database covers nuclear magnetic resonance spectra ( H-, C-, N-, O-, F-, P-NMR), infrared spectra (IR), and mass spectra (MS). In addition, experimental conditions (instrument, solvent, temperature), coupling constants, relaxation time, and bibliographic data are included. The data is cross-linked to CAS Registry, Beilstein, and NUMERIGUIDE. 

Patents are important for companies to protect their research. In industry, novelties are first published in patents and nowhere else. This means that only up to 10% of the information contained in patents is available through other information systems. In addition, to avoid redundant investigations, companies can monitor the research of competitors and can claim new developments (products, compounds, etc.) on their own. 

Beilstein Beilstein Information Systems, Inc. organic chemistry. nu- meric, struc- ture >8mio subst., >5 mio reactions 180 journals Beilstein Handbook MDL Information Systems GmbH commercial online, Chemweb, Crossfire quarterly wuAo.beilstein.- com... 

Gmelin MDL Information Systems GmbH, Germany inorganic and organometal-lie chemistry struct., numeric 1.4 mio 110 journals, Gynelin Handbook MDL commercial online periodi- cally uwio.nuili.com... 

CRIS/USDA Current Research Information System USDA/ eSREES/ I STM research projects in agriculture, food, nutrition, and forestry biblio. variable autiior submis- sions CRIS online annual http //cris.es- rees.usda.gov/... 

DayCart is a software cartridge which offers a range of operation on an Oracle database, such as complete structure, similarity, and substructure search. The software can be obtained from Daylight Chemical Information Systems, Inc. (Mission Viejo CA) URL www.daylight.com... 

CACTVS is a chemical information system which provides 2D and 3D complete structure, substructure, and similarity search on plain files of structures. The... 

Chemical Placard Response Information System, Commandant Instruction M. 16465.12A, U.S. Coast Guard, U.S. Department of Transportation, Washington, D.C. 

Sweets Cata/ogFi/e 7, ThermalandMoisture Protection, Sweets Div., McGraw-HiU Information System Co., New York, 1978. 

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