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See detailAn integrated modelling strategy between a CFD and an FE software: Methodology and application to compartment fires
Tondini, Nicola; Morbioli, Andrea; Vassart, Olivier et al

in Journal of Structural Fire Engineering (2016), 7(3), 217-233

Purpose: This paper aims to present the assumptions and the issues that arise when developing an integrated modelling methodology between a computational fluid dynamics (CFD) software applied to ... [more ▼]

Purpose: This paper aims to present the assumptions and the issues that arise when developing an integrated modelling methodology between a computational fluid dynamics (CFD) software applied to compartment fires and a finite element (FE) software applied to structural systems. Design/methodology/approach: Particular emphasis is given to the weak coupling approach developed between the CFD code fire dynamics simulator (FDS) and the FE software SAFIR. Then, to show the potential benefits of such a methodology, a multi-storey steel-concrete composite open car park was considered. Findings: Results show that the FDS–SAFIR coupling allows overcoming shortcomings of simplified models by performing the thermal analysis in the structural elements based on a more advanced modelling of the fire development, whereas it appears that the Hasemi model is more conservative in terms of thermal action. Originality/value: A typical design approach using the Hasemi model is compared with a more advanced analysis that relies on the proposed FDS–SAFIR coupling. [less ▲]

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See detailIntegrated multi sensor system for parallel in-situ monitoring of cell nutrients, metabolites and cell mass in biothechnological processes
Mross, S; Zimmerman, T; Winkin, N et al

in Proc. Eurosensors, CS02-1 (2015, September)

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See detailIntegrated multi-sensor system for parallel in-situ monitoring of cell nutrients, metabolites, cell density and pH in biotechnological processes
Mross, Stefan; Zimmermann, Tom; Winkin, N et al

in Sensors and Actuators. B, Chemical (2016)

We report on a multi-sensor system for the parallel in-situ monitoring of cell nutrients, metabolites, cell density and pH in biotechnological processes. The fabrication process of the sensor chip, based ... [more ▼]

We report on a multi-sensor system for the parallel in-situ monitoring of cell nutrients, metabolites, cell density and pH in biotechnological processes. The fabrication process of the sensor chip, based on a CMOS process flow, is suitable for integration into standard processes and mass production of the system. The integration of enzyme sensors for wide concentration ranges, an impedance-based sensor and a pH sensor on one silicon chip for in-situ applications in bioreactors, fabricated in a CMOS-based process flow, is demonstrated for the first time to our best knowledge. Measurements of glucose and lactate concentrations in a wide range are shown with linear ranges up to 600 mMand 900 mM, respectively. Cell density is determined via conductivity changes of a cell suspension and measurements are performed up to 15 g/l dry cell weight. The pH sensor is based on C-V measurements at an electrolyte-insulator semiconductor structure and able to measure pHin a range from pH3 to pH12. All sensors are successfully employed in the monitoring of cultures of Saccharomyces cerevisiae or Lactobacillus acidophilus. [less ▲]

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See detailIntegrated on-line sample clean-up using cation exchange restricted access sorbent for the LC determination of atropine in human plasma coupled to UV detection
Rbeida, O.; Christiaens, B.; Hubert, Philippe ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2005), 36(5), 947-954

A new, simple and fully automated liquid chromatographic (LC) method with UV detection has been developed for the direct determination of atropine in plasma. Sample clean-up was based on the use of cation ... [more ▼]

A new, simple and fully automated liquid chromatographic (LC) method with UV detection has been developed for the direct determination of atropine in plasma. Sample clean-up was based on the use of cation exchange restricted access material (RAM) in a pre-column, coupled to LC by means of a column switching system. After direct injection of a 200 microl-volume of plasma sample, the biological matrix was washed out for 10 min using a washing liquid composed of 2 mM lithium perchlorate adjusted to pH 3.0 and methanol (97:3; v/v). By rotation of the switching valve, atropine was then eluted in the back-flush mode for 2 min and transferred to the analytical column packed with octadecyl silica by the LC mobile phase constituted of a mixture of acetonitrile and potassium phosphate buffer (pH 3.0; 50 mM) containing 2 mM sodium heptanesulfonate (16:84; v/v). The UV detection was performed at 220 nm. The method was validated according to a new approach based on accuracy profile over a concentration range from 25 ng/ml, corresponding to the limit of quantitation, to 1000 ng/ml. The method was then applied for the determination of atropine in plasma after intravenous administration to hospitalised patients. [less ▲]

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See detailIntegrated optical components on atom chips
Eriksson, S.; Trupke, Michael; Powell, H. F. et al

in The European Physical Journal D (2005), 35(1), 135--139

We report on the integration of small-scale optical components into silicon wafers for use in atom chips. We present an on-chip fibre-optic atom detection scheme that can probe clouds with small atom ... [more ▼]

We report on the integration of small-scale optical components into silicon wafers for use in atom chips. We present an on-chip fibre-optic atom detection scheme that can probe clouds with small atom numbers. The fibres can also be used to generate microscopic dipole traps. We describe our most recent results with optical microcavities and show that a sufficiently high finesse can be achieved to enable single-atom detection on an atom chip. The key components have been fabricated by etching directly into the atom chip silicon substrate. [less ▲]

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See detailIntegrated power control analysis of DFIG wind turbines considering structural flexibility
Chen, Qiongzhong ULg; Bruls, Olivier ULg

in Proceedings of the ASME 2011 International Design Engineering Technical Conference & Computers and Information in Engineering Conference IDETC/CIE 2011 (2011, August)

Doubly-fed induction generators (DFIGs) are commonly used in variable-speed wind turbines for more power extraction. Unlike previous research on DFIG wind turbines, which typically uses an equivalent ... [more ▼]

Doubly-fed induction generators (DFIGs) are commonly used in variable-speed wind turbines for more power extraction. Unlike previous research on DFIG wind turbines, which typically uses an equivalent lumped mass model of the drive train dynamics, but does not include detailed aerodynamic/mechanical representations, this paper investigates on the modelling and control of DFIG wind turbines by following a systematic approach based on a flexible multibody simulation software. The wind turbine structure, generator and control subsystem models are modularly developed for the S4WT package (Samcef for Wind Turbines), which is a user interface for the analysis of wind turbines. An extension of the finite element method is available in the flexible multibody dynamics solver, for the representation of the non-mechanical components, i.e., the generator and the control system, so that the coupled mechatronic system is simulated in a strongly coupled way. This integrated approach is less intricate and more robust than approaches based on an external DLL or co-simulation methods. The objective of this work is to analyze the control-generator-structure interactions in a wind turbine system. The power optimization control is elaborated in detail. A 2MW DFIG wind turbine prototype model is presented for validation. Dynamic analysis including the control effects and the influence of the structural flexibility is provided in an overall range. [less ▲]

Detailed reference viewed: 72 (10 ULg)
See detailIntegrated Prediction
Backhaus, J; Crispi, G; Djenidi, Salim ULg et al

in ECOPS Coastal Zone Steering Group (Ed.) Prediction of Change in Coastal Seas: Grand Challenges for European Cooperation in Coastal Marine Science. (1994)

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See detailIntegrated prism-free coupled surface plasmon resonance biochemical sensor
Lenaerts, Cedric ULg; Hastanin, Juriy ULg; Pinchemel, Bernard et al

in Proceedings of SPIE (2012), 8424

Detailed reference viewed: 82 (27 ULg)
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See detailIntegrated Project with Focus on Energy Transition and Circular Economy for Developing Engineering Students' Soft Skills
Léonard, Grégoire ULg; Pfennig, Andreas ULg; Toye, Dominique ULg et al

Poster (2016, September 05)

The present work reports the experience of an integrated project developed at the University of Liege for master students in chemical engineering. The goals are to promote the acquisition of soft skills ... [more ▼]

The present work reports the experience of an integrated project developed at the University of Liege for master students in chemical engineering. The goals are to promote the acquisition of soft skills and to consolidate technical knowledge by integrating and linking chemical engineering disciplines usually taught separately. A case study was selected to address some of the challenges related to energy transition: students had to design the energy system of a remote island and make it as energy independent and CO2-neutral as possible by 2030. The course of action during the academic year, the assessment of soft skills, and the tools offered to ease the mentoring and encourage the acquisition of soft skills are described. Not all implemented techniques performed equally well, and this project finally appeared to be a challenge for the teaching team as well. 1 Introduction and background Over the last few years, University authorities, industrial partners as well as national and international experts that evaluated the education quality of our Department (AEQES, CTI) strongly suggested that opportunities should be offered to students to increase their soft skills as part of their curriculum. Moreover, many developments in chemical engineering are related to energy transition and circular economy, which are both transdisciplinary to conventional lectures. In this paper, we present methods and mentoring tools developed to teach students technical and soft skills for multi-disciplinary topics. 2 Description of the integrated project Objectives and constraints were defined at the onset of the project for both technical and soft skills. The technical objective was to propose an energy system that would make Reunion Island as energy independent and CO2-neutral as possible by 2030. This idea originated in the challenge set by the Eurecha 2015 student contest[1], for which students had to design facilities for a sheikhdom: electricity, water recycling, production of fertilizers… In our case, Reunion Island (~850 000 inhabitants) was considered as a case study as it is remote, has large biomass resources and high potential for renewable energies. Besides the objectives mentioned above and in order to force students to look at chemical engineering processes, the treatment of wastewater was imposed as well as the use of a synthetic liquid fuel as energy carrier. The targeted soft skills included working in large groups of minimum 4 students, efficient communication of results in English - both written and oral -, ability to integrate knowledge from various disciplines, development of critical mind and demonstration of independent and creative thinking. 3 Course of actions A team of 8 professors and senior scientists mentored the project and contributed to its assessment. The 10-ECTS project was divided in two parts. In the fall semester, students made global energy balances to design the energy system that would fulfill the objectives. As a result, a Sankey diagram of the energy flows on Reunion Island by 2030 was produced to allow for an overview of the available Island’s resources and needs, as well as of processes that can make the link between resources and needs. In the spring semester, two processes identified in the first part, namely the synthesis of bio-ethanol and bio-methanol, were modelled in more details using commercial software. Different tools were used to encourage student initiatives and work: • The use of a shared on-line portfolio for students to gather their documents improved their internal communication, but this remained a marginal channel for communication with teachers • In the fall semester, students orally presented progress reports every two weeks. After a feedback to students, the teaching team met to discuss the achievements and set the objectives for the next two weeks. This was very positive for the communication inside the teaching team. However, presentations every fortnight implied a work overload for students that had to constantly focus on preparing the presentations. • From the beginning, students were strongly encouraged to reach out to field experts whose contacts were provided. However, they preferred to rely mostly on Internet as their main source of information and reached out only rarely for help and usually very late. • In the fall semester, students had to designate new team leaders in turn every fortnight. This was abandoned as it prevented the establishment of clear structures in the group, reducing its efficiency. • In the spring semester, work tables allowed students to work directly with the teacher specialized in their task. This was appreciated by students and teachers, and it needs to be further encouraged. • Help in the group organization and interactions was provided by the PSGO (psychology of groups and organizations). This also included videoscopy, i.e. filming the students during their presentations and analyzing the records with them. This help was appreciated by students. The assessment was based on technical results for 60%, and soft skills for 40%. The evaluation of technical skills was done partly by all teachers equally and partly by teachers whose expertise was the closest to the technical sub-tasks. For soft skills, efficient communication, creativity in the work and results and links with conventional lectures were assessed. Critical thinking was evaluated through the relevance of qualitative and quantitative results and discussions. Group work was assessed by the teachers as well as by students through mutual evaluation. 4 Conclusions and perspectives The integrated project gave students a first opportunity to improve their soft skills along with their technical knowledge. It also improved their communication skills and their fluency in English. The teaching team proposed different mentoring techniques to encourage efficient work, with varying results. Finally, as the assessment ignored soft skills improvements, it may be modified by evaluating soft skills all year long so both the final result and the observed improvements contribute to the grade. Reference Eurecha, The European Committee for the Use of Computers in Chemical Engineering Education, 2015. Announcement for student contest problem competition 2015. http://bari.upc.es/eurecha/. [less ▲]

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See detailAn Integrated Quantitative Method to Simultaneously Monitor Soil Erosion and Non-Point Source Pollution in an Intensive Agricultural Area
Ma, Li; Bu, Zhaozhong; Kerr, Philip et al

in Pedosphere (2014)

In China, some areas with intensive agricultural use are facing serious environmental problems caused by non-point source pollution (NPSP) as a consequence of soil erosion (SE). Until now, simultaneous ... [more ▼]

In China, some areas with intensive agricultural use are facing serious environmental problems caused by non-point source pollution (NPSP) as a consequence of soil erosion (SE). Until now, simultaneous monitoring of both NPSP and SE is difficult due to the intertwined effects of differences in crop type, topography and management in these areas. Based on meteorological data, a Geographic Information System (GIS) database and soil and water samples, we propose a new integrated method to monitor SE and NPSP simultaneously and apply to an intensive agricultural area (Nanjing area, ~6 000 km2) in eastern China. The results showed that the levels of soil total nitrogen (TN), total phosphorus (TP), ammonium nitrogen (AN) and available phosphorus (AP) can be used to assess and predict the extent of NPSP and SE status in the study area. Most SE and the greatest NPSP loads occurred between April to August. The most seriously affected area in terms of SE and NPSP was the Jiangning District, implying that the effective management of SE and NPSP in this area should be considered a priority. The sub-regions with higher vegetation coverage contributed to less SE and NPSP, affirming the conclusions of previous studies, namely that vegetation is an effective factor in controlling SE and NPSP. This study shows that the application of our quantitative method has both high precision and reliability for the simultaneous monitoring of SE and NPSP occurring in intensive agricultural areas. [less ▲]

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See detailIntegrated Research and Protected Spaces: a New Role for STS?
Thoreau, François ULg

Poster (2009, September 10)

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See detailIntegrated Simulation and Reduced-Order Modeling of Controlled Flexible Multibody Systems
Bruls, Olivier ULg

Doctoral thesis (2005)

A mechatronic system is an assembly of technological components, such as a mechanism, sensors, actuators, and a control unit. Recently, a number of researchers and industrial manufacturers have ... [more ▼]

A mechatronic system is an assembly of technological components, such as a mechanism, sensors, actuators, and a control unit. Recently, a number of researchers and industrial manufacturers have highlighted the potential advantages of lightweight parallel mechanisms with respect to the accuracy, dynamic performances, construction cost, and transportability issues. The design of a mechatronic system with such a mechanism, requires a multidisciplinary approach, where the mechanical deformations have to be considered. This thesis proposes two original contributions in this framework. First, a modular and systematic method is developed for the integrated simulation of mechatronic systems, which accounts for the strongly coupled dynamics of the mechanical and non-mechanical components. The equations of motion are formulated using the nonlinear Finite Element approach for the mechanism, and the block diagram language for the control system. The time integration algorithm relies on the generalized-alpha method, known in structural dynamics. Hence, well-defined concepts from mechanics and from system dynamics are combined in a unified formulation, with guaranteed convergence and stability properties. Several applications are treated in the fields of robotics and vehicle dynamics. Usual methods in flexible multibody dynamics lead to complex nonlinear models, not really suitable for control design. Therefore, a systematic nonlinear model reduction technique is presented, which transforms an initial high-order Finite Element model into a low-order and explicit model. The order reduction is obtained using the original concept of Global Modal Parameterization: the motion of the assembled mechanism is described in terms of rigid and flexible modes, which have a global physical interpretation in the configuration space. The reduction procedure involves the component-mode technique and an approximation strategy in the configuration space. Two examples are presented: a four-bar mechanism, and a parallel kinematic machine-tool. Finally, both simulation and modeling tools are exploited for the dynamic analysis and the control design of an experimental lightweight manipulator with hydraulic actuators. A Finite Element model is first constructed and validated with experimental data. A reduced model is derived, and an active vibration controller is designed on this basis. The simulation of the closed-loop mechatronic system predicts remarkable performances. The model-based controller is also implemented on the test-bed, and the experimental results agree with the simulation results. The performances and the other advantages of the control strategy demonstrate the relevance of our developments in mechatronics. [less ▲]

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See detailIntegrated simulation of mechanical structures and their control system
Bruls, Olivier ULg; De Boe, Pascal; Duysinx, Pierre ULg et al

in Proc. of the 2nd Int. Conf. on Advanced Computational Methods in Engineering (ACOMEN) (2002, May)

This paper concerns the modeling and the integrated numerical simulation of flexible mechanisms subject to the action of a digital control system. A general method is proposed, based on the formalism of ... [more ▼]

This paper concerns the modeling and the integrated numerical simulation of flexible mechanisms subject to the action of a digital control system. A general method is proposed, based on the formalism of flexible multibody systems (MBS) using the Finite Element Method (FEM). Nonlinear e ects in the mechanical structure or in the control system can be taken into account. The numerical simulation tool is applied to design an active control system in a hot-dip galvanizing line, which aims at reducing the vibrations of the steel strip. [less ▲]

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See detailAn integrated software for building design.
Andre, Philippe ULg; Nicolas, Jacques ULg

in Proceedings of the Congres Building design, technology and occupant well-being in temperate climates. (1993, February)

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See detailAn integrated software for passive solar building design
Andre, Philippe ULg; Nicolas, Jacques ULg

in Proceedings of ISES 93 Congress (1993, August)

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See detailAn Integrated Software for Scantling Optimization and Least Production Cost
Rigo, Philippe ULg

in Ship Technology Research = Schiffstechnik (2003)

Detailed reference viewed: 66 (4 ULg)
See detailIntegrated strategic infrastructure networks in Enrope
Marchal, Jean ULg

Report (1998)

Detailed reference viewed: 14 (0 ULg)