Contribution pour une évaluation des nouvelles formes de « co-construction » réflexives au sein du régime de l’innovation en Wallonie

Conference (2009, March 02)

Abstract : Poles of competitiveness were launched in Walloon region as a policy for innovation support. This policy aims to reinforce cooperation and partnering between industry and research universities ... [more ▼]

Abstract : Poles of competitiveness were launched in Walloon region as a policy for innovation support. This policy aims to reinforce cooperation and partnering between industry and research universities in the region: critical mass, excellence, international size should be reached through the construction of large cooperative projects. Thes new dynamics were in line with the earlier ones which were developed as separate branches of research policy for universities and firms. The governance of the poles, largely controlled by the firms representatives, promoted the development of new forms of interactions between the institutional segments of the Triple Helix of innovation: state – industry – university. Universities stepped quickly in the poles dynamics and took advantage of the opportunity to reinforce their presence in the regional economic framework. Administration was not associated to the launch of the government-defined process and encountered difficulties stepping in the process and entering into these new modes of governance, more supportive than normative. The innovation model at the basis of the policy initiative sets a strong systemic stance to the dynamics of knowledge production but fails to deliver enough reflexivity to go beyond the narrow instrumental rationality of innovation. [less ▲]

Contribution technologique à l'élaboration de produits alimentaires "trans-free". Comportement thermique de mélanges binaires.

Poster (2006, November 17)

Contribution théorique et numérique a la modélisation des écoulements mixtes diphasiques hautement transitoires

in Proc. Int. Conf. SimHydro 2010: Hydraulic modeling and uncertainty (2010)

Contribution to a jaw behavior and deformation study

Conference (2006, May)

Contribution to Entanglement Theory, Applications in Atomic Systems and Cavity QED

Doctoral thesis (2011)

We introduce in this thesis two entanglement detection criteria, the Schrödinger-Robertson partial transpose inequality, which can be implemented experimentally in a variety of systems and generalized N ... [more ▼]

We introduce in this thesis two entanglement detection criteria, the Schrödinger-Robertson partial transpose inequality, which can be implemented experimentally in a variety of systems and generalized N-qubit concurrences, which can be used to evaluate multipartite entanglement in N-qubit mixed states. Then, we investigate ways to experimentally produce entanglement by giving a theoretical model which successfully describes the dipole blockade effect. We study its possible applications in systems of two and three two-level atoms as well as its relations with the EITeffect in systems of two three-level atoms. Finally, we show the possibility of two-photon processes in a system of two two-level atoms embedded in a cavity by using perturbation theory and a full master equation approach. We unveil interesting features of blockade and transparency in such cavity QED systems. [less ▲]

Contribution to line design by accurate predetermination of severe but occasional stresses.

in Proceedings of the CIGRE session 1990 (1990, August 27)

Evaluation by simulation of different dynamic loadings are detailed. Including short-circuit, galloping and conductor breakage.

Contribution to pomegranate seeds conservation (Punica granatum L.) by osmotic dehydration

Doctoral thesis (2011)

The aim of this work was to create a complete conservation process of pomegranate seeds (Punica granatum L.). This process is essentially based on osmotic dehydration (OD), which was associated to ... [more ▼]

The aim of this work was to create a complete conservation process of pomegranate seeds (Punica granatum L.). This process is essentially based on osmotic dehydration (OD), which was associated to freezing and air-drying process. Several parameters were studied to optimize the process such as osmotic solution (sucrose, glucose, and sucrose/glucose and date juice with sucrose added), temperature (30, 40, and 50°C) and state of the fruit (fresh and frozen). All these conditions were linked to seed proprieties (texture, structure, and colour). The study of osmotic dehydration parameters (water loss (WL), solids gain (SG) and weight reduction (WR)) showed that most significant changes of mass transfer took place during the first 20 min of dewatering using frozen seeds, independently of temperature and sugar type. During this period, seeds water loss was estimated at 46% in sucrose, 41% in sucrose/glucose mix, 39% in date juice, and 37% in glucose. Mass transfer was slower starting from fresh fruit but led to a higher rate of WL at the end of the process. This fact can be explained by scanning electron microscopy, which showed damage of seed cell structure after freezing. This has practical consequences in terms of the modification of seeds texture. The same process also revealed a modification of seed texture and cell structure after osmotic dehydration. Using a sucrose solution and a temperature of 50°C favoured the best mass transfer. The determination of different water fractions of seed by differential scanning calorimetry (DSC) showed that the % of frozen water decreased 3.5 times contrary the % of unfreezable water that increased 2.5 times. This favours a better seeds conservation. During osmotic dehydration, there was a non negligible leaching of natural solutes from seeds into the solution, which might have an important impact on the sensorial and nutritional value of seeds. Using only osmotic dehydration could not maintain the stability of seeds during conservation. In fact, after the osmotic process, water activity of seeds was found to be higher than 0.9, allowing to the development of microorganisms and some undesirable reactions. As a consequence, a drying of the pomegranate seeds (during four hours) was investigated at three different temperatures (40, 50, and 60 °C) with air flow rate of 2 ms-1. Prior to the drying process, seeds were osmodehydrated in a sucrose solution (55°Brix) during 20 min at 50°C. The drying kinetics and the effects of OD and air-drying temperature on antioxidant capacity, total phenolic, colour, and texture were determined. This work is a contribution to the study of physico-chemical properties of pomegranate seeds (Punica granatum L.) during freezing, osmotic dehydration and drying. After the global process, the pomegranate seed characteristics lead to new industrial developments. [less ▲]

Contribution to the applied territorial intelligence: reasoned catalog of territorial information available on internet and sources in Europe

in International Conference of Territorial Information. Papers on Tools and Methods of Territorial Intelligence. (2009)

This article gives a report on the territorial collection of information for the local actors in the whole of Europe (EU 27). It deals with various sources available in Europe in a centralized and ... [more ▼]

This article gives a report on the territorial collection of information for the local actors in the whole of Europe (EU 27). It deals with various sources available in Europe in a centralized and decentralized way. An inventory was carried out for indicators selected within the framework of the method CATALYSE of confrontation of the populations needs with the services available to answer it. Various examples of information sources for the territories (“observatories”) are also putted forward. The reasoned catalog treats methods of cartographic representation for the various indicators. It also highlights the variability of the indicators definitions according to the European suppliers, and the difficulties of harmonization and use. [less ▲]

A contribution to the audit of an air-conditioning system: modeling, simulation and benchmarking

(2006, December)

This paper intends to show how benchmarks can help in the audit of a HVAC system and how these benchmarks can be generated. The work presented is part of the European “AUDITAC” project. How can an auditor ... [more ▼]

This paper intends to show how benchmarks can help in the audit of a HVAC system and how these benchmarks can be generated. The work presented is part of the European “AUDITAC” project. How can an auditor declare that a given HVAC is “consuming too much”? He can’t make any judgment, if not having some reference, i.e. some “benchmarks” available. Focus is given here to cooling regime, but even then, heating cannot be forgotten (for example, the remaining heating demand can be satisfied thanks some recovery on the condensers of the chillers). The dramatic question is: what should be the consumption(s) for such a building, in such a climate, with such occupancy, such internal loads and such actual indoor environment? Better than to look for a (very hypothetical) global weather index, similar to heating degree-days, it seems more rational to run a simulation model on a few thousands of hours, corresponding to one (or to several) cooling season(s). Current performances of simulation tools make this approach very expedient. The climate can then be considered as it is, without any simplification. The main simplification is still welcome on the system (building + HVAC) side, in order to get calculation robustness, easy understanding and easy parameter identification. In this perspective, the building has to be subdivided in a very limited number of zones and only a few components of the HVAC system have to be included in the simulation model, with as simple as possible control strategies. [less ▲]

Contribution to the Characterization of Scroll Machines in Compressor and Expander Modes

Doctoral thesis (2008)

This thesis contributes to the knowledge and the characterization of scroll machines and their systems. It is based on experimental and modeling works carried out on: a) A hermetic scroll compressor used ... [more ▼]

This thesis contributes to the knowledge and the characterization of scroll machines and their systems. It is based on experimental and modeling works carried out on: a) A hermetic scroll compressor used inside an air-cooled water chiller. b) An oil-free open-drive scroll expander integrated into an Organic Rankine Cycle (ORC) power system. c) Open-drive scroll compressor and expander used in a Liquid Flooded Ericsson Cycle Cooler (LFEC). Such a system uses the liquid flooding of the compressor and of the expander to approach isothermal compression and expansion processes. New semi-empirical models of the scroll compressor and expander were proposed and existing models improved. A deterministic model of the scroll expander was established. The model associates a geometrical description of the machine with a thermodynamic description of the expansion process. This model was validated for the two expanders investigated experimentally. The model validation revealed that the performance of the expanders is mainly affected by the supply pressure drop and by the internal leakages. Using the validated model, parametric studies were carried out to investigate the variation of the performance of both expanders with modification of their design and with the operating parameters. The thesis also investigated the scroll machines from the point of view of their integration into thermal systems. A first experimental investigation was carried out on an air-cooled chiller. The scroll compressor semi-empirical model, with its parameters identified on the basis of published manufacturer data, was used as a refrigerant flow meter. The analysis of the experimental data allowed a better understanding of the chiller operation and a better identification of its model parameters (such as the fan and the hot gas bypass control models). A second experimental investigation was carried out on an ORC power system, working with R123. In order to select the most appropriate fluid, the performances achieved with four different fluids were compared by simulation. The experimental study confirmed that the scroll expander is a good candidate for an ORC system: the tested prototype presented a good performance (the maximum global isentropic effectiveness achieved was 68%). Using an ORC simulation model, parametric studies were carried out to investigate the effects of the expander characteristics and operating conditions on the cycle performance. The latter is mainly affected by the expander internal leakage and by the liquid subcooling at the condenser exhaust. A third experimental investigation was performed on a LFEC working with nitrogen as refrigerant and alkyl-benzene oil as flooding liquid. Experimental data was used to identify the parameters of the scroll compressor and expander semi-empirical models. Parametric studies were performed to identify the different factors affecting their performance. One of the undesirable features of the machines is the increase of the supply and exhaust pressure drops with the increase of oil quantity. [less ▲]