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Albarazanchi A.,University of Strasbourg | Gerard P.,ICube | Ambs P.,Upper Alsace University | Meyrueis P.,University of Strasbourg
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

There is an increasing demand for optical elements having the functionalities of hybrid devices, such as the combination of a Fresnel lens and a diffraction grating. These new devices can be used in many applications, such as in optical spectrometers, optical precision measurement systems and diffractive optical systems for enhancing the efficiency of third generation photovoltaic solar cells. There is also a growing need for developments of a cost-effective technology to fabricate compact optical devices. Therefore the motivation of our project is to find a new model of the G-Fresnel (i.e. grating and Fresnel lens) taking into account the utilization of the electromagnetic theory for the rigorous analysis of its behavior. In this paper, a novel method is proposed and employed to design a G-Fresnel device that has only one structure layer with subwavelength features, and that focuses and separates different bands of light spectra in the same focal plane. The device performance has been studied through the use of rigorous electromagnetic theory, by using the Finite Difference Time Domain (FDTD) for the study of the near field and the Angular Spectrum Method (ASM) for the study of the propagation in the far field. The optimal design of the G-Fresnel profiles depends on the profile of the Fresnel lenses that minimize the longitude chromatic aberration, and also on the diffraction grating with high first order diffraction efficiency. The verification of the G-Fresnel model that we propose shows high diffraction efficiency and a good performance in separation for a broadband light spectrum. This promising G-Fresnel model could be used to increase the efficiency of third generation photovoltaic cells. © 2014 SPIE.

Petit M.,University of Namur | Goepp V.,ICube
Proceedings - CIE 45: 2015 International Conference on Computers and Industrial Engineering | Year: 2015

Business-IT alignment (BITA) is considered as a crucial challenge faced by enterprises. Several Enterprise-Architecture based solutions (that we call Enterprise Architecture Frameworks - EAFs for BITA) have been proposed in order to help to address this problem. However, currently, there is no systematic evaluation of EAFs to check if they are appropriate for BITA. In this paper, we propose a framework to help the evaluation of EAFs for BITA. The framework contains requirements coming from the ISO 15704 standard and some that we derive from the well-known Strategic Alignment Model of Henderson and Venkatraman. We then apply this evaluation framework to the de-facto standard EAF Archimate® proposed by the Open Group. The analysis allows us to identify a potential extension of Archimate® to make it more appropriate in a BITA context.

Goepp V.,ICube | Petit M.,University of Namur
ICEIS 2013 - Proceedings of the 15th International Conference on Enterprise Information Systems | Year: 2013

The Strategic Alignment Model (SAM) remains one of the most relevant and cited models aiming at helping managers to achieve business/IT (Information Technology) alignment. Several alternative approaches extend or improve this model. A notable stream of research suggests applying Enterprise Architecture principles complementarily or independently to the SAM. We analyze these proposals and argue that they are sometimes fuzzy and hard to compare because they all use a specific structure or vocabulary making the objectivation of their strengths and weaknesses difficult. Some common vocabulary and concepts such as those of the ISO 15704 standard on Enterprise Reference Architectures and Methodologies are needed to make their comparison rigorous. We report on our ongoing research, using this standard to analyse the SAM.

Boisselier D.,IREPA LASER | Sankare S.,IREPA LASER | Engel T.,ICube
Physics Procedia | Year: 2014

The implementation of the continuous 5-axis configuration can extend the limits of the Laser Direct Metal Deposition (LDMD) processes, especially when the complexity of the parts to be built is growing. In order to follow the profile of a part, we use the orientation of its growth axis. Although 5-axis machining is well known nowadays, LDMD processes require a specific optimization that depends on many parameters. Unlike conventional machining, it has to be noted that the speed variation tool tip affects the stability of deposition. Thus, we have to smooth trajectories in order to provide fluid movements and also to ensure the stability of deposition. This article describes the method and results in the optimization of trajectories to build metallic parts with freeform. Optical sensors have been implemented in the focusing unit in order to follow the variations of the laser-powder-substrate interaction and also to detect the process instabilities. Thanks to the right use of a new and large 5 axis machine and specific setting trajectories, manufacturing parts in 5-axis, with no concession on the construction rate has been possible. © 2014 The Authors. Published by Elsevier B.V.

Mamoghli S.,LGECO | Goepp V.,ICube | Botta-Genoulaz V.,INSA Lyon
Enterprise Information Systems | Year: 2015

Enterprise Resource Planning (ERP) systems offer standard functionalities that have to be configured and customised by a specific company depending on its own requirements. A consistent alignment is therefore an essential success factor of ERP projects. To manage this alignment, an ‘Operational Model Based’ method is proposed. It is based on the design and the matching of models, and conforms to the modelling views and constructs of the ISO 19439 and 19440 enterprise-modelling standards. It is characterised by: (1) a predefined design and matching order of the models; (2) the formalisation, in terms of modelling constructs, of alignment and misalignment situations; and (3) their association with a set of decisions in order to mitigate the misalignment risk. Thus, a comprehensive understanding of the alignment management during ERP projects is given. Unlike existing methods, this one includes decisions related to the organisational changes an ERP system can induce, as well as criteria on which the best decision can be based. In this way, it provides effective support and guidance to companies implementing ERP systems, as the alignment process is detailed and structured. The method is applied on the ERP project of a Small and Medium Enterprise, showing that it can be used even in contexts where the ERP project expertise level is low. © 2015 Taylor & Francis

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