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Learning from AI : new trends in database technology
Recently some researchers in the areas of database data modelling and knowledge representations in artificial intelligence have recognized that they share many common goals. In this survey paper we show the relationship between database and artificial intelligence research. We show that there has been a tendency for data models to incorporate more modelling techniques developed for knowledge representations in artificial intelligence as the desire to incorporate more application oriented semantics, user friendliness, and flexibility has increased. Increasing the semantics of the representation is the key to capturing the "reality" of the database environment, increasing user friendliness, and facilitating the support of multiple, possibly conflicting, user views of the information contained in a database
Concepts and their Use for Modelling Objects and References in Programming Languages
In the paper a new programming construct, called concept, is introduced.
Concept is pair of two classes: a reference class and an object class.
Instances of the reference classes are passed-by-value and are intended to
represent objects. Instances of the object class are passed-by-reference. An
approach to programming where concepts are used instead of classes is called
concept-oriented programming (CoP). In CoP objects are represented and accessed
indirectly by means of references. The structure of concepts describes a
hierarchical space with a virtual address system. The paper describes this new
approach to programming including such mechanisms as reference resolution,
complex references, method interception, dual methods, life-cycle management
inheritance and polymorphism.Comment: 43 pages. Related papers: http://conceptoriented.com
Steps Towards a Method for the Formal Modeling of Dynamic Objects
Fragments of a method to formally specify object-oriented models of a universe of discourse are presented. The task of finding such models is divided into three subtasks, object classification, event specification, and the specification of the life cycle of an object. Each of these subtasks is further subdivided, and for each of the subtasks heuristics are given that can aid the analyst in deciding how to represent a particular aspect of the real world. The main sources of inspiration are Jackson System Development, algebraic specification of data- and object types, and algebraic specification of processes
Generic Model Refactorings
Many modeling languages share some common concepts and principles. For example, Java, MOF, and UML share some aspects of the concepts\ud
of classes, methods, attributes, and inheritance. However, model\ud
transformations such as refactorings specified for a given language\ud
cannot be readily reused for another language because their related\ud
metamodels may be structurally different. Our aim is to enable a\ud
flexible reuse of model transformations across various metamodels.\ud
Thus, in this paper, we present an approach allowing the specification\ud
of generic model transformations, in particular refactorings, so\ud
that they can be applied to different metamodels. Our approach relies\ud
on two mechanisms: (1) an adaptation based mainly on the weaving\ud
of aspects; (2) the notion of model typing, an extension of object\ud
typing in the model-oriented context. We validated our approach by\ud
performing some experiments that consisted of specifying three well\ud
known refactorings (Encapsulate Field, Move Method, and Pull Up Method)\ud
and applying each of them onto three different metamodels (Java,\ud
MOF, and UML)
The C++0x "Concepts" Effort
C++0x is the working title for the revision of the ISO standard of the C++
programming language that was originally planned for release in 2009 but that
was delayed to 2011. The largest language extension in C++0x was "concepts",
that is, a collection of features for constraining template parameters. In
September of 2008, the C++ standards committee voted the concepts extension
into C++0x, but then in July of 2009, the committee voted the concepts
extension back out of C++0x.
This article is my account of the technical challenges and debates within the
"concepts" effort in the years 2003 to 2009. To provide some background, the
article also describes the design space for constrained parametric
polymorphism, or what is colloquially know as constrained generics. While this
article is meant to be generally accessible, the writing is aimed toward
readers with background in functional programming and programming language
theory. This article grew out of a lecture at the Spring School on Generic and
Indexed Programming at the University of Oxford, March 2010
Attribute oriented induction with star schema
This paper will propose a novel star schema attribute induction as a new
attribute induction paradigm and as improving from current attribute oriented
induction. A novel star schema attribute induction will be examined with
current attribute oriented induction based on characteristic rule and using non
rule based concept hierarchy by implementing both of approaches. In novel star
schema attribute induction some improvements have been implemented like
elimination threshold number as maximum tuples control for generalization
result, there is no ANY as the most general concept, replacement the role
concept hierarchy with concept tree, simplification for the generalization
strategy steps and elimination attribute oriented induction algorithm. Novel
star schema attribute induction is more powerful than the current attribute
oriented induction since can produce small number final generalization tuples
and there is no ANY in the results.Comment: 23 Pages, IJDM
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