Enseigner la conception collaborative à distance avec des technologies innovantes : retours d’expérience du SDC et du HIS

Cet article décrit deux dispositifs de collaboration à distance innovants, utilisés notamment pour l’apprentissage de la conception collaborative à distance. Ces deux dispositifs, à savoir le Hybrid Ideation Space (HIS) et le Stu-dio Digital Collaboratif (SDC) sont basés sur le même paradigme d’esquisse numérique, bien que les objectifs sous-jacents et leur mise en œuvre soient différents. Nous décrivons dans l’article les objectifs sous-tendant leur développement, synthétisons l’approche pédagogique et décrivons un retour d’expérience sur ces deux situations complémentaires

La graphique de l'intention: Transfert et appropriation d'intentions graphiques en collaboration.

peer reviewedCet article traite de la passation graphique d'une intention et révèle, par l'intermédiaire d'expérimentations ciblées, quels composants graphiques soutiennent particulièrement bien ou mal cette passation. Les résultats suggèrent d'apporter une attention toute particulière, que l'on soit concepteur-collaborateur ou développeur d'interfaces de soutien à la collaboration distante, aux courbes dites "principales". Celles-ci semblent effectivement être garantes d'une intention graphique potentiellement mieux transmise et mieux capturée - l'essence graphique d'une collaboration distante efficace

Evolution des pratiques en conception: une approche ergonomique compréhensive des objets médiateurs

peer reviewedCet article examine l’évolution et la modulation des usages des « objets médiateurs » en design industriel depuis l’avènement des outils de CAO (Conception Assistée par Ordinateur). Ces outils ont longtemps été étudiés en regard des avantages et inconvénients que leur utilisation constituait pour le processus de conception, et toujours en comparaison des outils dits « traditionnels » (dessins à main levée, maquettes) [9 ; 5]. L’article suggère d’étudier plutôt ces outils, médiateurs de l’activité de conception, pour leur complémentarité qui apparaît parfois très en amont du processus de conception (dès la phase conceptuelle). Les bases théoriques qui structurent l’ensemble de l’intervention sont présentées et discutées à la lumière de cette suggestion tout comme les principaux résultats d’une intervention in situ, pour une objectivation des nouvelles pratiques « métier »

A Virtual Desktop's First evaluation for an Augmented Design Process

Many CAD tools already allow to design and directly manipulate ideas in a digital way. However, designers still use pen and paper during the early design phase of their projects. Indeed, existing CAD tools constraint creative work. There is a need for a spontaneous human computer interaction in design computing. In order to answer to this need, we develop an integrated aided design tool based on a Virtual Desktop. The designer sits in front of a classical desk where s/he can design and manipulate drawings and generated models. This paper describes the observations made during experiment about Virtual Desktop’s use by a designer. The experiment demonstrates that the immersive aspect of our system interface modifies the relationship between the designer and his/her model and, by the way, how this relation generates a new type of augmented interaction.Peer reviewe

Perimeter Control with Heterogeneous Cordon Signal Behaviors: A Semi-Model Dependent Reinforcement Learning Approach

Perimeter Control (PC) strategies have been proposed to address urban road network control in oversaturated situations by monitoring transfer flows of the Protected Network (PN). The uniform metering rate for cordon signals in existing studies ignores the variety of local traffic states at the intersection level, which may cause severe local traffic congestion and ruin the network stability. This paper introduces a semi-model dependent Multi-Agent Reinforcement Learning (MARL) framework to conduct PC with heterogeneous cordon signal behaviors. The proposed strategy integrates the MARL-based signal control method with centralized feedback PC policy and is applied to cordon signals of the PN. It operates as a two-stage system, with the feedback PC strategy detecting the overall traffic state within the PN and then distributing local instructions to cordon signals controlled by agents in the MARL framework. Each cordon signal acts independently and differently, creating a slack and distributed PC for the PN. The combination of the model-free and model-based methods is achieved by reconstructing the action-value function of the local agents with PC feedback reward without violating the integrity of the local signal control policy learned from the RL training process. Through numerical tests with different demand patterns in a microscopic traffic environment, the proposed PC strategy (a) is shown robustness, scalability, and transferability, (b) outperforms state-of-the-art model-based PC strategies in increasing network throughput, reducing cordon queue and carbon emission

Investigations on Ni-Ti-Al ohmic contacts obtained on p-type 4H-SiC

International audienceTransfer Length Method (TLM) based-structures were fabricated on 0.8 µm-thick epitaxial p-type Silicon Carbide (4H-SiC) layers. TLM mesas were defined by a 2 µm height using an SF 6 /O 2 reactive ion etching. TLM metal patterns were obtained by a lift-off procedure and electron beam deposition of Ni, Ti, Al and Pt. The patterned samples were annealed in Argon ambient at temperature ranging from 700°C up to 1000°C in a RTA furnace with a rapid heating ramp (up to 50°C/s) to complete the ohmic contact with the p-type SiC layer. Specific contact resistances were extracted from current/voltage measurements. To identify and follow the profile evolution of constituting element in the contacts and at the SiC/contact interface, the ohmic contacts were characterized using Secondary Ion Mass Spectrometry and Energy-Dispersive X-Ray spectroscopy before and after annealing. Ohmic contacts are obtained only for the Ni/Ti/Al and Ni/Ti/Al/Ni stacking layers and not for the Ti/Al/Ti/Ni and Ti/Al/Ti/Pt/Ni compositions. The specific contact resistance of Ni/Ti/Al/Ni stacking layers was observed to decrease from 2.7×10-4  .cm 2 at 700°C and 6.3×10-5 .cm 2 at 750°C to a minimal value of 1.5×10-5  .cm 2 at 800°C. Ohmic contacts are obtained with a reproducibility of 80 %

A Multidisciplinary architectural education facing Climate change.

peer reviewedTo deal with global issues we face such as climate change, the New European Bauhaus Initiative calls for empowering and educating citizens. According to the initiative, architecture and urban planning are only effective when an interdisciplinary approach is applied. This is even more important when integrating sustainability into architectural education. This paper presents the results of an experimental study conducted during four months of the first semester of a master's degree program in civil engineering and architecture at the University of Liège and as part of an integrated design process. The design studio is related to the Sustainable Architecture and Urban Design course that combines theoretical teaching and practice and allows 21 students to develop in-depth sustainability issues. To best respond to their architectural intentions and choices, several multidisciplinary contributions are provided by professionals and experts from several fields including architecture, building envelope, environmental quality, structure, fire safety, accessibility standards, fluids, heating, ventilation, and air-conditioning. Our exploratory study examines learning activities, teaching methods, as well as students’ outcomes, and interactions with experts collected via questionnaire and interview survey. The analysis reveals that sustainability issues are integrated through an interdisciplinary conceptual process within a holistic approach. Sustainability criteria are developed in coherence with all the functional, aesthetic, structural, and technological aspects of the design project. This paper argues for more Transfers between professional practice and teaching within a MULTIDISCIPLINARY DESIGN in order to foster awareness for future architects so that they can design the built environment in a responsible way

Collaborative design: Evolution of project’s information and role of the graphic interactions

peer reviewedFaced with challenges of new collaborative and digital design processes, it is necessary to understand how to support architectural design to articulate the information from the collaborative ideation (first creative moments of idea deployment) to the digital design phases that follow (such as BIM mo- dels specifications). The study presented here lies within the fields of design theory and com- putational design as our research question is to analyze collaborative design processes to qualify the evolution of the information characterizing the pro- ject and the design activities generating this evolution, notably through the role of graphic interactions. To achieve this goal, we changed the paradigm by considering the design- ers as transmitters of information, and the information as the heart of our questioning. As result, we highlighted some typical design activities to characterize the project, recurrent associations of information and finally the importance of graphical traces as a support of this characterization