Brace W.,Aalto University |
Journal of Engineering Design | Year: 2012
Complex system development activities, such as requirements analysis (RA) to requirements specification, implementation and verification, are well defined in the software engineering domain. Interests in using a model-driven engineering have increased in this domain. System-level RA and model-driven engineering may result in a significant improvement in engineering design. This paper presents a Checklist-Oriented Requirement Analysis (CORA) framework to develop and formalize requirements. CORA is an integrated framework that adopts a checklist concept and utilises logical reasoning operation in conjunction with information management to analyse systematically the initial requirements statement. An underground work machine is used as an application example to illustrate the proposed framework. © 2012 Copyright Taylor and Francis Group, LLC.
Charles Y.,University of Paris 13 |
Gasperini M.,University of Paris 13 |
Disashi J.,University of Paris 13 |
Journal of Materials Processing Technology | Year: 2012
The present work focuses on non-linear finite element simulations of the Disk Pressure Test, used for characterization of hydrogen embrittlement of metallic materials by bulging out a thin disk under gas pressure until failure. The modeling is based on both elastoplastic and diffusion computations at the macroscopic scale. Hydrogen sensitive cohesive elements are used for crack propagation. Comparison of numerical predictions with experimental data on steel and Inconel gives good agreement both on macroscopic displacement-load curves and on global hydrogen embrittlement features. © 2012 Elsevier B.V. All rights reserved.
Hammadi M.,LISMMA |
International Journal of Dynamical Systems and Differential Equations | Year: 2015
Several dynamical systems require parametric compact modelling of physical behaviour taking into account the tight coupling with the control system. In this paper, we present an approach combining meshfree method with multi-port technique for the analysis of physical systems modelled with partial differential equations. The meshfree technique used is based on radial basis functions and differential quadrature method. Thermal modelling and simulation of a power electronic converter is considered as an application to validate the proposed approach. Obtained results of temperatures and heat fluxes in different layers of the power converter are compared with finite element analysis. It is shown that with small stencil sizes, it is possible to produce solutions for complex systems with an accuracy comparable to finite element method, but with less computation time. Copyright © 2015 Inderscience Enterprises Ltd.
Robbe-Valloire F.,LISMMA |
Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology | Year: 2012
This article is based on an existing model to describe mixed lubrication between parallel surfaces. This model uses a statistical description of the microgeometry and includes summit and radius distributions. Depending on these geometric parameters, each asperity works with one of the five following lubrication mechanisms: piezoviscous hydrodynamic, elastohydrodynamic, elastic, elastoplastic, and full plastic. By summing the normal load obtained for each asperity, we derived the normal load for the entire contact. Discussion in this article is based on the repartition of asperities into each of these five possible mechanisms. We first analyze the parameters that are able to significantly change the limit between two neighboring regimes. The number of asperities associated with each regime is also considered. We also analyze the fraction of normal load transmitted by all asperities of a given regime. Generally, only a maximum of four regimes can generate significant contributions for a given situation. Depending on the operating conditions of the contact, these significant regimes change. Consequently, it seems very difficult to suggest reducing the number of regimes for a general description of mixed lubrication between parallel surfaces. Copyright © IMechE 2012.
Louis-Sidney L.,LISMMA |
Louis-Sidney L.,Renault S.A. |
Cheutet V.,LISMMA |
Lamouri S.,Arts et Metiers ParisTech |
And 2 more authors.
Engineering Applications of Artificial Intelligence | Year: 2012
The level of efficiency achieved in the diffusion of knowledge within an organisation is acknowledged to be a competitive advantage. As a result, various means have emerged to help share this knowledge. Among the various existing solutions, the use of parameterised files consistently encapsulating data of a refined level of granularity (e.g. figures, words, etc.) is a well-known practice. However, these files - which we will call Parameterised Knowledge Objects (PKOs) - often exhibit redundancy. This has led to a need for mapping, a fastidious work with no added value, which slows down the product redesign process. The goal of this article is to propose a conceptual model for the implementation of an automated tool to manage exchanges between these PKOs. The implementable nature of the model was validated by the development of a demonstrator, tested on an application provided by our industrial partner - the Renault Powertrain Technology Design Department. © 2011 Elsevier Ltd. All rights reserved.
Estampe D.,BEM Bordeaux Management School |
Lamouri S.,LISMMA |
Paris J.-L.,French National Center for Scientific Research |
Brahim-Djelloul S.,Institute National Of Commerce
International Journal of Production Economics | Year: 2013
Supply chain management creates value for companies, customers and stakeholders interacting throughout a supply chain. The strategic dimension of supply chains makes it paramount that their performances are measured. In today's performance evaluation processes, companies tend to refer to several models that will differ in terms of corporate organisation, the distribution of responsibilities and supply chain maturity. The present article analyzes various models used to assess supply chains by highlighting their specific characteristics and applicability in different contexts. It also offers an analytical grid breaking these models down into seven layers. This grid will help managers evolve towards a model that is more suitable for their needs. © 2010 Elsevier B.V.
Pialot O.,LISMMA |
Procedia CIRP | Year: 2014
Design of more sustainable products is a fundamental priority in our society. New opportunities for facilitating the dissemination of the remanufacturing approach, the dissemination of Product-Service Systems, or for increasing the lifetime of product (three ways for rationalizing materials) are proposed by the integration of upgrades which are functional enrichments brought to the product. This paper aims to show the need of product upgradability through a concrete study focused on four presuppositions: upgradability concept requires (P1) a potential pool of disposed devices which still work, (P2) a need for adaptability of product to user needs, (P3) a need for adaptability of product to the competition, and is related to (P4) an accumulation of product dissatisfactions over time. The first results show the necessity to consider a new sort of "evolutionary" products for sustainability: Innovations with multiples upgrade cycles. © 2014 Published by Elsevier B.V.
Cluzel F.,École Centrale Paris |
Yannou B.,École Centrale Paris |
Millet D.,LISMMA |
Leroy Y.,École Centrale Paris
International Journal of Life Cycle Assessment | Year: 2014
Purpose: This paper considers the variabilities that exist in the exploitation of a complex industrial system. Our scenario-based LCA model ensures the reliability of results in situations where the system life cycle is very uncertain, where there is substantial lack of data, and/or where time and resources available are limited. It is also an effective tool to generate exploitation recommendations for clients. Methods: Existing quantitative uncertainty methods in LCA require a huge amount of accurate data. These data are rarely available in simplified and upstream LCA for complex industrial systems. A scenario-based approach is the best compromise between acceptable quality of results and resources required. However, such methods have not yet been proposed to improve the environmental knowledge of the system in the case of exploitation scenarios. The method proposed here considers a limited number of scenarios (three or four) that are defined using the Stanford Research Institute matrix. Using results from past projects, relevant parts of the system are listed, and expert knowledge and parameters are associated with these parts and quantified. A classical LCA process then provides the results for the different scenarios. Results and discussion: The method was applied to an Alstom Grid AC/DC conversion substation for the primary aluminum industry. A previous study had limited scope, as the life cycle was poorly understood. Relevant parts were, thus, clearly identified as follows: spare parts program, transport failures, preventive and corrective maintenance, updates and revampings, lifetime modulation, and end-of-life. Four scenarios were considered as follows: best case, worst case, baseline (expected future), and a highly different alternative. Results show the pertinence of considering several exploitation scenarios when the life cycle is not predictable, as the environmental impacts may vary widely from one case to another. A sensitivity analysis also shows that some relevant parts such as updates and revampings will need to be carefully considered in futures studies. Conclusions: The consideration of three exploitation scenarios (best case, baseline, and worst case) appears to be extremely pertinent when considering simplified LCA of industrial systems with high uncertainties and limited time and resources. This model is also very useful to generate good practice and recommendations towards clients, thus initiating a dialog centered on eco-design and continuous improvement. © 2013 Springer-Verlag Berlin Heidelberg.
Rameau J.-F.,Dassault Systemes |
Mechanism and Machine Theory | Year: 2015
A mechanism is a set of rigid links interconnected together with ideal joints and featuring at least one degree of freedom. An overconstrained mechanism is mobile provided the links' dimensions fulfill a certain relation named the "mobility condition". The dimensions are not independent from each other and the goal is to obtain this mobility condition. Firstly, parameters are divided into two categories: dimensional parameters and positional parameters. Dimensional parameters represent links' sizes and positional parameters represent the relative positions between the links. The closure equation models the geometric problem by capturing the relationships between the two types of parameters. The principle of the paper is to generate the mobility condition by applying Groebner basis computation to the closure equation. Three methods are presented and investigated. The first one is called the univariate polynomial method (UNIPOL); the second method is called multi-order derivation method (MOD) and the third one is called the finitely separated configurations (FISECO) method. Practical implementation of these various techniques is explained by using a standard computer algebra system. The three methods are applied on a 2D overconstrained mechanism. © 2015 Elsevier Ltd. All rights reserved.
Hammadi M.,LISMMA |
Choley J.-Y.,LISMMA |
Penas O.,LISMMA |
SIMULTECH 2012 - Proceedings of the 2nd International Conference on Simulation and Modeling Methodologies, Technologies and Applications | Year: 2012
Preliminary optimization of mechatronic systems is an extremely important step in the development process of multi-disciplinary products. However, long computing time in optimization based on multi-domain modelling tools need to be reduced. Surrogate model technique comes up as a solution for decreasing time computing in multi-disciplinary optimization. In this paper, an electric vehicle has been optimized by combining Modelica modelling language with surrogate model technique. Modelica has been used to model the electric vehicle and surrogate model technique has been used to optimize the electric motor and the transmission gear ratio. Results show that combining surrogate model technique with Modelica reduces significantly computing time without much decrease in accuracy.