See also: Model
In data processing, a model aims to structure the data, the treatments, and flows of information between entities.
The data-processing models developed in the Années 1970 were all of the type Entité-relation. One can quote:
These models comprised three principal components in general:
- Given S: Data model
- the treatment S: Model of treatments
- the Flow (network): diagrams or graphs of flow (see Diagram of data flow).
One traditionally distinguished three levels from concern:
- the conceptual level,
- the logical or organisational level,
- the physical level.
These models were generally applied on a field, scale applications even, but seldom company scale, so that one found inconsistencies from one field to another in the same company. From where interfaces difficult to establish when the data were not in the same way defined from one field to another.
In the Years 1990, the need for replacing or for renovating the affected applications by the problem of Datation (see data-processing Passage to the year 2000 and Y2K) involved the implementation of Business packages integrated on a scale Entreprise S. the Donnée S and applications were consistency often according to the structure of these software packages, which in general were conceived in the spirit of the Entity-relation model .
The Unified Modeling Language (UML) made it possible to define a common language so that these projects are concluded in the most coherent possible way between all the methods which had been employed.
Insufficiency of the models employed in the years 1970 1990
Several phenomena reveal an insufficiency of the models employed:
- the treatment S often were conceived in a linear way, and take little account of the interactions between the Recipients, which play an increasingly important part today (Lobbying, ONG,…) ;
- the Donnée S taken into account appear now of the structured systems of databases type,… and the not structured documents (texts, images, its,…) who now represent most of the immaterial Capital in the universe of the Web, are not taken more into account in the traditional models;
- the Flux (network) between the companies almost did not exist (except exception of the car), they intervened only between financial institutions; today the Flux (network) between firms generate needs for protection of the informational Patrimoine, when bunches of companies cooperate on innovating projects (Poles of competitiveness);
- the models raise also question compared to the Souveraineté of regional whole in construction like the European Union. How to protect the Innovation in the Poles of competitiveness? In other words, how to satisfy criteria of Sovereignty domestic and Westphalian in a whole like the European Union?
- These models push with a valorization according to especially economic criteria, inherited the 19th century (see Factor of production); the Factor of production “Ground” was neglected starting from second half of the 19th century, when one spoke about Capital/Travail;
- the economic Aggregate S (GDP) and the National accountings were structured according to these criteria; the third pillar of the Sustainable development (environmental) was not truly integrated in the analyzes of the traditional data-processing models; the quality standards of product prove to be insufficient to give completely an account of the stakes Sociétaux;
- Some economic Théories current try to reinstate the factor ground, by defining a Capital naturalness, with the risk that the Durabilité is conceived like a durability]] low and not like a strong Durabilité;
The implementation of the Norme S IAS/IFRS in Europe since 2005 has also very important consequences on the way of modelling the Information systems. Indeed, it is expected that the immaterial Capital companies is Comptabilisé in a Norme IAS, like Intangible fixed assets. However, much of experts think that the value of the companies is made up to 60/at least 70% of Actifs immaterial.
To that is added the fact that the Computer's resources are increasingly made up of Ressources Web, therefore of Texte S, of Image S, its, which one can reach by indexed search engines. These resources can be identified by a uniform Identifiant of resource (in English Uniform Resource To identify, URI).
There exist work on a possible standardization of the “Métadonnée S” which would give access these resources (see Dublin Core).
See tooModel object
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