A Generic Model Driven Methodology for Extending Component Models

Software components have interesting properties for the development of scientific applications such as easing code reuse and code coupling. In classical component models, component assemblies are however still tightly coupled with the execution resources they are targeted to. Dedicated concepts to abstract assemblies from resources and to enable high performance component implementations have thus been proposed. These concepts have not achieved widespread use, mainly because of the lack of suitable approach to extend component models. Existing approaches -- based on ad-hoc modifications of component run-times or compilation chains -- are complex, difficult to port from one implementation to another and prevent mixing of distinct extensions in a single model. An interesting trend to separate application logic from the underlying execution resources exists; it is based on meta-modeling and on the manipulation of the resulting models. This report studies how a model driven approach could be applied to implement abstract concepts in component models. The proposed approach is based on a two step transformation from an abstract model to a concrete one. In the first step, all abstract concepts of the source model are rewritten using the limited set of abstract concepts of an intermediate model. In the second step, resources are taken into account to transform these intermediate concepts into concrete ones. A prototype implementation is described to evaluate the feasibility of this approach

Enabling Connectors in Hierarchical Component Models

The continual growth of computing and storage capabilities enables scientific numerical applications to integrate more and more phenomena in their computations at the price of increased complexity. Hierarchical component models appear as an interesting approach to handle such complexity. However defining and implementing efficient interactions between hierarchical components is a difficult task, especially in the case of parallel and distributed applications. Connectors originating from Architecture Description Languages (ADL) offer a promising solution to this problem. There are however some cases where a simple combination of hierarchy and connectors in a single component model forces users to choose between an efficient implementation of components and their black box behavior. This paper describes HLCM, a model with connectors and hierarchy that provides /open connections/ as a mechanism to describe component interface that enhances encapsulation and eases component implementation replacement while supporting efficient interactions. Complex interactions such as data sharing and parallel method calls are successfully supported by HLCM. An implementation, based on model transformation and on CCM, illustrates its feasibility and benefits.La croissance continue des capacités de calcul et de stockage permet aux applications numériques d'intégrer un nombre croissant de phénomènes dans leurs calculs au prix d'une complexité accrue. Les modèles de composants hiérarchiques apparaissent comme une approche intéressante pour gérer cette complexité. Cependant, définir et implémenter des interactions efficaces entre composants hiérarchiques est une tâche difficile, d'autant plus dans le cas d'applications parallèles et distribuées. Les connecteurs issus des langages de description d'architecture (ADL) offrent une solution prometteuse à ce problème. Il y a cependant des cas où une simple combinaison de la hiérarchie et des connecteurs dans un modèle de composants unique oblige l'utilisateur à faire un choix entre des mises en œuvres efficaces pour les composants et leur comportement «boîte noire». Ce papier décrit HLCM, un modèle avec connecteurs et hiérarchie qui fournit le concept de /connexions ouvertes/ pour decrire les interfaces de composants. Ce méchanisme améliore l'encapsulation et facilite le remplacement des mises en œuvre de composant tout en permettant des interactions efficaces. Des interactions complexes telles que le partage de données ou les invocations de méthodes parallèles sont gérées avec succès par HLCM. Une mise en œuvre basée sur une transformation de modèle et sur CCM est utilisée pour illustrer sa faisabilité et ses bénéfices

Overview of the mean of production used for FSW

The Friction Stir welding process is now introduced in production plants. More and more applications are developed and the most part of the work is now centered on the mean of production to be used. Institut de Soudure and Arts et Métiers ParisTech are working on this subject since mid of 2005. The results of this work is a recognize knowledge on the methodology for qualifying a Friction Stir Welding Equipment [1]. In the same time, and based on this work, Institut de Soudure has bought a new kind of Friction Stir Welding machine based on a KUKA Robot

Experimental investigation of the influence of the FSW plunge processing parameters on the maximum generated force and torque

The paper presents the results of an experimental investigation, done on the friction stir welding (FSW) plunging stage. Previous research works showed that the axial force and torque generated during this stage were characteristic for a static qualification of a FSW machine. Therefore, the investigation objectives are to better understand the relation between the processing parameters and the forces and torque generated. One of the goals is to find a way to reduce the maximum axial force and torque occurring at the end of the plunging stage in order to allow the use of a flexible FSW machine. Thus, the influence of the main plunge processing parameters on the maximum axial force and torque are analysed. In fact, forces and torque responses can be influenced by the processing parameter. At the end, a diagram presenting the maximum axial force and torque according to the processing parameters is presented. It is an interesting way to present the experimental results. This kind of representation can be useful for the processing parameters choice. They can be chosen according to the force and torque responses and consequently to the FSW machine capacities

High Performance Composition Operators in Component Models

International audienceScientific numerical applications are always expecting more computing and storage capabilities to compute at finer grain and/or to integrate more phenomena in their computations. Even though, they are getting more complex to develop. However, the continual growth of computing and storage capabilities is achieved with an increase complexity of infrastructures. Thus, there is an important challenge to define programming abstractions able to deal with software and hardware complexity. An interesting approach is represented by software component models. This chapter first analyzes how high performance interactions are only partially supported by specialized component models. Then, it introduces HLCM, a component model that aims at efficiently supporting all kinds of static compositions

Methodology for qualifying a Friction Stir Welding equipment

The objective of this research work is the industrialization of the friction stir welding process in order to provide tools to industrials to select and qualify a machine for their FSW applications. This paper presents a methodology to determine the Friction Stir Welding equipment adequate to an application. The adequate equipment can be every machine that can perform friction stir welds. This paper presents a short review, based on literature survey, of the existing friction stir welding equipments. Then, the methodology developed is presented. It is based on the studying of the interactions between the tool and the workpiece

Qualification of a robotized Friction Stir Welding System

This paper presents an experimental methodology to determine a Friction Stir Welding (FSW) means of production based on the experimental study of the tool / material mechanical interactions generated during the welding operation. These two stages have been identified as being characteristic for the qualification of a FSW equipment. This paper presents the experimental results of the parametric study done on the plunging and welding phases. Ranges of forces and torques diagrams were established according to the processing parameters, in order to qualify a means of production and select the process parameters allowing the operation on the available FSW equipment

Determining the ability of a high payload robot to perform FSW applications

This paper presents an experimental methodology to determine a Friction Stir Welding (FSW) means of production based on the experimental study of the tool / material mechanical interactions generated during the welding operation. These two stages have been identified as being characteristic for the qualification of a FSW equipment. This paper presents the experimental results of the parametric study done on the plunging and welding phases. Ranges of forces and torques diagrams were established according to the processing parameters, in order to qualify a means of production and to select the processing parameters allowing the operation on the available FSW equipment

A Low Level Component Model enabling Resource Specialization of HPC Applications

Scientific applications are still getting more complex, e.g. to improve their accuracy by taking into account more phenomena. Moreover, computing infrastructures are continuing their fast evolution. Therefore, software engineering is becoming a major issue to achieve easiness of development, portability, simple maintenance, while achieving high performance. Software component model is a promising approach, which enables to manipulate the software architecture of an application. However, existing models do not capture enough resource specificities. This paper proposes a low level component model (L2C) that supports directly native connectors such as MPI, shared memory and method invocation. L2C is intended to be used as a back end by a ''compiler'' (such as HLCM) to generate an application assembly specific to a given machine. This paper shows on a typical domain decomposition use case that \llc can achieve the same performance as native implementations, while gaining benefits such as enabling resource specialization capabilities.Les applications scientifiques continuent de devenir de plus en plus complexes, par exemple pour améliorer leur précision en intégrant davantage de phénomènes à simuler. Par ailleurs, les infrastructures de calcul continuent leur rapide évolution. Ainsi, l'ingénierie logicielle devient un défi très important afin de permettre une facilité de développement, la portabilité des codes, et une maintenance acceptable tout en permettant de hautes performances. Les modèles de composants logiciels offrent une approche prometteuse en permettant de manipuler l'architecture logicielle d'une application. Cependant, les modèles existant ne permettent pas de capturer suffisamment les spécificités des ressources de calcul. Cet article propose un modèle de composant logiciel ''bas niveau'' (L2C) qui permet l'intègration native de connecteurs tels que MPI, la mémoire partagée ou l'invocation de méthode. L2C est destiné à être utilisé en tant que langage de sortie d'un ''compilateur'' (tel que HLCM) générant un assemblage d'une application spécifique à une machine et à une exécution. Cet article montre sur un cas d'étude typique de décomposition de domaines que L2C permet d'atteindre les même performances que les applications natives, tout en offrant des possibilités d'optimisation par rapport aux capacités des ressources

Experimental investigation of the influence of the FSW plunge processing parameters on the maximum generated force and torque

The paper presents the results of an experimental investigation, done on the friction stir welding (FSW) plunging stage. Previous research works showed that the axial force and torque generated during this stage were characteristic for a static qualification of a FSW machine. Therefore, the investigation objectives are to better understand the relation between the processing parameters and the forces and torque generated. One of the goals is to find a way to reduce the maximum axial force and torque occurring at the end of the plunging stage in order to allow the use of a flexible FSW machine. Thus, the influence of the main plunge processing parameters on the maximum axial force and torque are analysed. In fact, forces and torque responses can be influenced by the processing parameter. At the end, a diagram presenting the maximum axial force and torque according to the processing parameters is presented. It is an interesting way to present the experimental results. This kind of representation can be useful for the processing parameters choice. They can be chosen according to the force and torque responses and consequently to the FSW machine capacities