Results 1 
7 of
7
Optimisation Modelling for Software Developers
"... Abstract. Software developers are an ideal channel for the distribution of Constraint Programming (CP) technology. Unfortunately, including even basic optimisation functionality in an application currently requires the use of an entirely separate paradigm with which most software developers are not ..."
Abstract

Cited by 4 (2 self)
 Add to MetaCart
Abstract. Software developers are an ideal channel for the distribution of Constraint Programming (CP) technology. Unfortunately, including even basic optimisation functionality in an application currently requires the use of an entirely separate paradigm with which most software developers are not familiar. We suggest an alternative interface to CP designed to overcome this barrier, and describe a prototype implementation for Java. The interface allows an optimisation problem to be defined in terms of procedures rather than decision variables and constraints. Optimisation is seamlessly integrated into a wider application through automatic conversion between this definition and a conventional model solved by an external solver. This work is inspired by the language CoJava, in which a simulation is automatically translated into an optimal simulation. We extend this idea to support a general interface where optimisation is triggered ondemand. Our implementation also supports much more advanced code, such as object variables, variablesized collections, and complex decisions. 1
Rewriting Constraint Models with Metamodels
"... An important challenge in constraint programming is to rewrite constraint models into executable programs calculating the solutions. This phase of constraint processing may require translations between constraint programming languages, transformations of constraint representations, model optimizatio ..."
Abstract

Cited by 3 (2 self)
 Add to MetaCart
An important challenge in constraint programming is to rewrite constraint models into executable programs calculating the solutions. This phase of constraint processing may require translations between constraint programming languages, transformations of constraint representations, model optimizations, and tuning of solving strategies. In this paper, we introduce a pivot metamodel describing the common features of constraint models including different kinds of constraints, statements like conditionals and loops, and other firstclass elements like object classes and predicates. This metamodel is general enough to cope with the constructions of many languages, from objectoriented modeling languages to logic languages, but it is independent from them. The rewriting operations manipulate metamodel instances apart from languages. As a consequence, the rewriting operations apply whatever languages are selected and they are able to manage model semantic information. A bridge is created between the metamodel space and languages using parsing techniques. Tools from the software engineering world can be useful to implement this framework.
Towards an alignment of declarative modelling and modeltomodel transformation languages
 In Informatik 2009, Lecture Notes in Informatics
, 2009
"... Abstract: Declarative modeling and model driven software engineering seem to be two fields of research with completely different focus. However, the term “modeling” is used by both communities and both communities claim to use “declarative ” techniques. In this paper we give a small overview on som ..."
Abstract

Cited by 1 (1 self)
 Add to MetaCart
(Show Context)
Abstract: Declarative modeling and model driven software engineering seem to be two fields of research with completely different focus. However, the term “modeling” is used by both communities and both communities claim to use “declarative ” techniques. In this paper we give a small overview on some of the differences of both fields and present our modeltomodel transformation language which brings together constraint solving, optimization, and modeltomodel transformation. The language can be seen as an example how intuitively both communities can integrate to explore new applications. 1
DOI: 10.1007/9783642044250_8 Automatically Discovering Hidden Transformation Chaining Constraints
, 2010
"... Abstract. Model transformations operate on models conforming toprecisely defined metamodels. Consequently, it often seems relatively easy to chain them: the output of a transformation may be given as input to a second one if metamodels match. However, this simple rule has some obvious limitations. F ..."
Abstract
 Add to MetaCart
Abstract. Model transformations operate on models conforming toprecisely defined metamodels. Consequently, it often seems relatively easy to chain them: the output of a transformation may be given as input to a second one if metamodels match. However, this simple rule has some obvious limitations. For instance, a transformation may only use a subset of a metamodel. Therefore, chaining transformations appropriately requires more information. We present here an approach that automatically discovers more detailed information about actual chaining constraints by statically analyzing transformations. The objective is to provide developers who decide to chain transformations with more data on which to base their choices. This approach has been successfully applied to the case of a library of endogenous transformations. They all have the same source and target metamodel but have some hidden chaining constraints. In such a case, the simple metamodel matching rule given above does not provide any useful information. 1
Author manuscript, published in "The eight symposium on abstraction, reformulation, and approximation, Lake Arrowhead: United States (2009)" Rewriting Constraint Models with Metamodels
"... languages or predicates in logic languages. We propose to embed this collection of concepts in a socalled metamodel, that is a model of constraint models. This pivot metamodel describes the relations between concepts and it encodes in an abstract manner the rules for constraint modeling. This is a ..."
Abstract
 Add to MetaCart
languages or predicates in logic languages. We propose to embed this collection of concepts in a socalled metamodel, that is a model of constraint models. This pivot metamodel describes the relations between concepts and it encodes in an abstract manner the rules for constraint modeling. This is a considerable improvement of our previous work (Chenouard, Granvilliers, and Soto 2008) which was restricted to a onetomany mapping approach from a particular modeling language. Moreover, the translations to obtain Flat sCOMMA models were handcoded and model structures are always flattened like for FlatZinc models (Nethercote et al. 2007). Previous model transformations were also specific to Flat sCOMMA and its structure (e.g. there is no object and no loop to manage). Our pivot metamodel is independent of modeling languages and our approach offers more flexibility in getting efficient executable models. The rewriting process can be seen as a threesteps procedure. During the first step, the user constraint model is parsed and a metamodel instance is created. During the last step, the resulting program is generated from a metamodel instance. These two steps constitute a bridge between languages — the grammar space — and models — the model space. The middle step may implement rewriting operations over metamodel instances, for instance to transform constraint representations from an integer model to a boolean model. The main interest is to manipulate concepts rather than syntactic constructions. As a consequence, the rewriting operations can be expressed with clarity and they apply whatever languages are chosen. An interesting work is about the rulebased programming
Using ATL to define advanced and flexible constraint model transformations
"... Abstract. Transforming constraint models is an important task in recent constraint programming systems. Userunderstandable models are defined during the modeling phase but rewriting or tuning them is mandatory to get solvingefficient models. We propose a new architecture allowing to define brid ..."
Abstract
 Add to MetaCart
Abstract. Transforming constraint models is an important task in recent constraint programming systems. Userunderstandable models are defined during the modeling phase but rewriting or tuning them is mandatory to get solvingefficient models. We propose a new architecture allowing to define bridges between any (modeling or solver) languages and to implement model optimizations. This architecture follows a modeldriven approach where the constraint modeling process is seen as a set of model transformations. Among others, an interesting feature is the definition of transformations as conceptoriented rules, i.e. based on types of model elements where the types are organized into a hierarchy called a metamodel. 1