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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)

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See detailIntegrated strategic infrastructure networks in Enrope
Marchal, Jean ULg

Report (1998)

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See detailIntegrated structure and control design for mechatronic systems with configuration-dependent dynamics
Da Silva, Maíra Martins; Bruls, Olivier ULg; Desmet, Wim et al

in Mechatronics (2009), 44(9), 10161025

This paper considers the optimal design of mechatronic systems with configuration-dependent dynamics. An optimal mechatronic design requires that, among the structural and control parameters, an optimal ... [more ▼]

This paper considers the optimal design of mechatronic systems with configuration-dependent dynamics. An optimal mechatronic design requires that, among the structural and control parameters, an optimal choice has to be made with respect to design specifications in the different domains. Two main challenges are treated in this paper: the non-convex nature of the optimization problem and the difficulty in modeling serial machines with flexible components and their embedded controllers. The optimization problem is treated using the direct design strategy which considers simultaneously structural and control parameters as variables and adopts non-convex optimization algorithms. Linear time-invariant and gain-scheduling PID controllers are addressed. This methodology is exploited for the multi-objective optimization of a pick-and-place assembly robot with a gripper carried by a variable-length flexible beam. The resulting design tradeoffs between system accuracy and control efforts demonstrate the advantage of an integrated design approach for mechatronic systems with configuration-dependent dynamics. 2009 Elsevier Ltd. All rights reserved. [less ▲]

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See detailIntegrated system for decision help in urban mobility Management: Towards sustainable urban area development, VISUTRANS
Danoh, Charlemagne ULg; Ndiaye, Alassane-Ballé ULg; Marchal, Jean ULg

in WIT Transactions on Ecology and the Environment (2010), 142

Urban transport problems have become more widespread and severe than ever in both industrialised and developing countries alike. Facing this situation, there is a real need in developing new strategies ... [more ▼]

Urban transport problems have become more widespread and severe than ever in both industrialised and developing countries alike. Facing this situation, there is a real need in developing new strategies and innovative tools for transportation and town-planning as well as economic activities (public or private) within the area. The current tools and systems for solving transport problems are based on using several sub-management tools related to transportation infrastructures, town-planning, road traffic, environmental effects…which are not sufficiently in interaction. These solutions lead to severe handicap for urban homogenous and mastered development. That is why the “Urban mobility” has to be rethought. The main idea in this article concerns the development a multimodal, prospective and flexible tool for sustainable development of urban area which could help the decision makers in urban transportation fields. [less ▲]

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See detailIntegrated Two-phase Drift-flux Models for Modeling Sediment Transport
Kerger, François ULg; Dewals, Benjamin ULg

in Proceedings of the Symposium on Two-phase Modelling for Sediment Dynamics in Geophysical Flows (2011, April)

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See detailAn integrated view of technical, economic and social factors influencing sustainabiligy of sixteen local European cattle breeds
Martin-Collado, D.; Diaz, C.; Choroszy, Z. et al

in Book of Abstracts of the 60th Annual Meeting of the European Association for Animal Production (2009, August)

This study aims to identify common patterns influencing dynamics and sustainability of 16 local European cattle breeds from Belgium, Estonia, Finland, France, Holland, Ireland, Italy and Spain. A broad ... [more ▼]

This study aims to identify common patterns influencing dynamics and sustainability of 16 local European cattle breeds from Belgium, Estonia, Finland, France, Holland, Ireland, Italy and Spain. A broad range of factors related to technical (e.g. farm size, cows/ha, land ownership), economic (e.g. cattle importance on farm and family income, type of market) and social (e.g. farmers and stakeholders attitude) aspects were surveyed on a total of 401 farms. Discriminant Analysis has been used to study the implications that heterogeneity within and across countries and breeds may have in making inferences in across country or breed analyses. Thus, farms were classified according to country and breeds. Then the objective was to evaluate how all factors available allow us to distinguish such classes. The analyses provided the percentage of observations (farms) that should not be included in the pre-defined groups (country and breed) according to the variables considered. When only economic variables were considered in the analyses, 36% and 59% of farms were incorrectly assigned to their country and breed, respectively. However, considering technical variables the proportions went down to 33% and 45%. Finally, when both groups of variables were considered 20% and 35% of farms were incorrectly assigned. To what extent these mismatches may allow us to identify general patterns has to be evaluated. [less ▲]

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See detailIntegrated water management policy, the river contract in Wallonia, an experience of a participatory water management.
Rosillon, Françis ULg; Vander Borght, Paul ULg

in Coenen, Marleen; Sacile, Roberto; Meire, Patrick (Eds.) et al Integrated water management IWM-2003. Pilot study (2003)

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See detailIntegrated “omics” approaches to investigate the chemical aspects of symbiosis in termites and potential application in ligno-cellulosic use.
Bauwens, Julien ULg; Matteotti, Christel ULg; Brognaux, Alison ULg et al

Scientific conference (2010, May 05)

Cellulosic bioethanol could be one of the solutions to satisfy the increasing demand in renewable energy. The most limitative problem is the efficiency of cellulose transformation into fermentable sugars ... [more ▼]

Cellulosic bioethanol could be one of the solutions to satisfy the increasing demand in renewable energy. The most limitative problem is the efficiency of cellulose transformation into fermentable sugars. Investigations to select new glycosyl hydrolases are an interesting approach that constitutes a potential opportunity to improve the valorization of lignocellulosic materials. Three major types of glycosyl hydolases are generally produced by organism’s that are able to efficiently use cellulosic compounds: the endoglucanases, the exoglucanases/cellobiohydrolases and the β-glucosidases. In the ability to transform lignocellulosic materials by animals, symbioses are generally observed with a range of micro-organisms including bacteria, protists and/or fungi that largely (or completely) contribute to the production of the needed enzymatic complexes. In termites, such active enzymes are produced in the insect digestive tract, by the termite insect itself or by symbiotic organisms. Within lower termites gut, such as in our model Reticulitermes santonensis (Feytaud), protists and bacteria are associated and involved in a complex symbiotic system. To investigate the respective role of the insect and different groups of symbionts, multidisciplinary “omics” approaches were here developed including proteomics (ESI-LC-MS-MS, 2D-Dige gel coupled with MALDI-TOF mass spectrometry for protein identification), genomics (with a metagenomic approach based on large cDNA bank construction), metabolomics (LC-MS stragety for carbohydrate degradation product characterization). Moreover, microorganism isolation was used to investigate and characterize glycosyl hydrolases diversity and activity in R. santonensis. The integration of this broad range of “omics” techniques allowed characterizing the role of symbionts in insects in a fundamental approach and to invtigate the chemical ecology of xylophagous insects but also corresponding to an efficient way to promote the selection of efficient enzymatic activities to potentially produce biofuels based on the use of existing lignocellulosic materials. [less ▲]

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See detailDe integratie van zorgkundigen in de thuisverpleging
Moons, P.; Gosset, Christiane ULg; Beckers, Jacqueline ULg et al

Report (2009)

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See detailIntegrating axle weight restrictions in a two-dimensional vehicle routing problem with sequence based loading
Pollaris, Hanne; Braekers, Kris; Caris, An et al

Scientific conference (2014, June)

A mixed integer linear programming model for a two-dimensional capacitated vehicle routing problem (2L-CVRP) with sequence based loading and axle weight restrictions is provided. To the authors’ knowledge ... [more ▼]

A mixed integer linear programming model for a two-dimensional capacitated vehicle routing problem (2L-CVRP) with sequence based loading and axle weight restrictions is provided. To the authors’ knowledge, it is the first time that axle weight restrictions are incorporated in a VRP. Axle weight limits impose a great challenge for transportation companies. Trucks with overloaded axles represent a significant threat for traffic safety and may cause serious damage to the road surface. Transporters face high fines when violating these limits. The problem is based on a real-world problem from a Belgian logistics service provider. The demand of the customers consists of europallets. Pallets can be placed in two horizontal rows inside the vehicle. No vertical stacking is allowed. The center of gravity of the pallets inside the vehicle is calculated to determine the axle weights. Results of the model are compared to results of a 2L-CVRP with sequence based loading without axle weight restrictions. Numerical experiments demonstrate that the model performs adequately and that the integration of axle weight constraints in vehicle routing models is necessary for a feasible route planning. [less ▲]

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See detailIntegrating coarse-scale uncertain soil moisture data into a fine-scale hydrological modelling scenario
Vernieuwe, H.; De Baets, B.; Minet, Julien ULg et al

in Hydrology & Earth System Sciences (2011), 15

Detailed reference viewed: 9 (0 ULg)