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Bidart, France

Lartigau J.,ESTIA | Coureau J.-L.,University of Bordeaux 1 | Morel S.,University of Bordeaux 1 | Galimard P.,University of Bordeaux 1 | Maurin E.,CNRS Research Laboratory for Historical Monuments
International Journal of Fracture | Year: 2015

Glued-in-rods in timber structures lead to overcome the use of traditional bolted connections, preserve a large part of the original timber and offer aesthetic benefits. Several research programs were achieved to improve the mechanical knowledge of this technique, exhibiting experimentally the influence of materials and the effect of the geometric configuration. From these experimental results, some design rules predicting the axial strength are available, but a common criterion is still lacking. This paper relates to experimental investigations and finite element computations on glued-in rods, with the aim of providing a better knowledge about their mechanical behavior until failure. An experimental campaign is carried out on single glued-in rod connections. The finite element modeling reproduces the experimental configuration: it exhibits significant normal stress (to the interface) at the onset of the bonding, in comparison with shear stress. Within the framework of equivalent linear elastic fracture mechanics, resistance curves in mode I and mode II are established for each specimen. Finally, a mixed mode fracture criterion (I/II) is used to describe the fracture process zone development at the wood-adhesive interface (failure zone). An analytical formulation is then proposed allowing the evaluation of peak load of each specimen, which highlights a new approach for the design of such connections. © 2014, Springer Science+Business Media Dordrecht.

Ghouaiel N.,ESTIA IRIT | Cieutat J.-M.,ESTIA | Jessel J.-P.,CNRS Toulouse Institute in Information Technology
ACM International Conference Proceeding Series | Year: 2014

An augmented reality system is used to complete the real world with virtual objects (computer generated) so they seem to coexist in the same space as the real world. The concept of plasticity [4][5] was first introduced for Human Computer Interaction (HCI). It denotes the ability of an HCI interface to fit the context of use defined by the user, the environment and the platform. We believe that plasticity is a very important notion in the domain of augmented reality. Therefore, we rely on it in order to introduce the concept of adaptive augmented reality. This concept is based on the triplet (user, environment and platform) constituting the context of use. Adaptive augmented reality can foster functional ability, ease of use and portability of new augmented reality applications. Thus, we describe in this paper three applications showing the adaptation of augmentation based on three variables: the scene illumination, the distance to the target and the ambient noise.

Legardeur J.,ESTIA | Legardeur J.,University of Bordeaux 1 | Boujut J.F.,French National Center for Scientific Research | Tiger H.,French National Center for Scientific Research
Research in Engineering Design | Year: 2010

This paper presents the results of an empirical study focused on the observation and analysis of an innovative design process. We have had the opportunity to observe and participate in the early phase of a new innovative project within a design office of a truck manufacturer. Our observations based on the actor-network theory highlight the importance of the various design rationales carried by the actors involved. The results of this study show the weakness and complexity of an innovative process within a highly constrained environment. We particularly show that carrying out innovation requires different viewpoints with regard to the object of the design to evolve along with the network of actors and the organisation involved. The issue of product and process integration involving knowledge transfer between actors throughout the design process is also discussed here. As a result, we highlight the importance of rethinking the interface role played by the material expert (in our case) and, in line with other works, we put forward the "interface actor" as the key network actor involved during the early development phases. To provide the network and the interface actor with a means to share information and co-operate during these informal early design phases we propose some features of a new web-based information system and the basis for a debate on the idea lifecycle management concept as a solution to the issue of innovative idea information structuring. © 2010 Springer-Verlag London Limited.

Vechiu I.,ESTIA | Gurguiatu G.,University of Galati | Rosu E.,University of Galati
2010 9th International Power and Energy Conference, IPEC 2010 | Year: 2010

This paper presents a three-phase Active Power Conditioner to improve power quality in microgrids based on renewable energy. A microgrid is a weak electrical grid which can be easily subject to disturbances. The Active Power Conditioner (APC) presented in this paper acts as an interface between renewable energy sources and the AC bus of a microgrid and uses an improved control strategy, which makes possible to inject energy in the microgrid, compensate the current harmonics and correct the power factor. Moreover, the proposed control strategy allows the line current at the point of common coupling (PCC) to be balanced and sinusoidal even when the load is unbalanced. Consequently, the voltage at the PPC becomes balanced. Simulation results show the validity of the innovative control strategy. ©2010 IEEE.

Takouachet N.,ESTIA | Legardeur J.,IMS | Lizarralde I.,ESTIA
ACM International Conference Proceeding Series | Year: 2014

Facilitation is proved to improve group problem-solving effectiveness, research new concepts and innovative solutions. This paper addresses facilitation role during a creative session in the digital environment. We evaluate existing collaborative software based on the metaphor of the sticky note and we show that they are designed for use without necessarily taking into account the presence of a facilitator. They offer however, a set of functions that are relevant to the group and its individuals. According to our findings, we suggest a set of principal features to fully integrate the role of the facilitator into digital creativity sessions. Copyright 2014 ACM.

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