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Ontology Transformations

Laurent Wouters, Marie-Pierre Gervais
2012 2012 IEEE 16th International Enterprise Distributed Object Computing Conference  
This paper deals with the problem, coming from an industrial context, of ontology transformations. EADS, as a major aircraft manufacturer faces the problem of integrating works of experts from different domains using different notations. Addressing this Domain-Specific Language (DSL) problem, we previously developed a solution based on OWL2 ontologies for the integration of multiple domains at the abstract syntax level. Our next step is then the production of visual concrete syntaxes from this
more » ... bstract syntax, for each domain. Considering this problem as a transformation issue, we raise the challenge of ontology transformations. We provide an OWL2-based rule language for the expression of such transformations. Validating this approach, our rule language has been implemented in a rule and transformation engine and tested on applications coming from the industry.
doi:10.1109/edoc.2012.18 dblp:conf/edoc/WoutersG12 fatcat:c54plymvgfejtbatrdpwhhmoam

xOWL: An Executable Modeling Language for Domain Experts

Laurent Wouters, Marie-Pierre Gervais
2011 2011 IEEE 15th International Enterprise Distributed Object Computing Conference  
doi:10.1109/edoc.2011.13 dblp:conf/edoc/WoutersG11 fatcat:2ya4pescwnhtlintwkh32ozaa4

Towards Semantic-Aware Collaborations in Systems Engineering

Laurent Wouters, Stephen Creff, Emma Effa Bella, Ali Koudri
2017 2017 24th Asia-Pacific Software Engineering Conference (APSEC)  
The design of nowadays complex systems requires a collaboration between a diversity of stakeholders: from domain experts to customers. For a collaboration to be efficient, the relevant information have to reach the right stakeholder at the right time in a format that is understandable to him/her. We propose a formal framework to integrate the meaning projected by stakeholders onto their data (the denotation), so that it can be unambiguously used by others. An implementation of this framework,
more » ... lying on the existing language xOWL (extension of OWL2 with behavioral constructs), is then provided to perform the semantic integration of the captured denotations in an MBSE approach.
doi:10.1109/apsec.2017.92 dblp:conf/apsec/WoutersCBK17 fatcat:xngrfjsmundvtjjrhjz3tn7pzy

Improving Nefiracetam Dissolution and Solubility Behavior Using a Cocrystallization Approach

Xavier Buol, Koen Robeyns, Camila Caro Garrido, Nikolay Tumanov, Laurent Collard, Johan Wouters, Tom Leyssens
2020 Pharmaceutics  
In this work, we are the first to identify thirteen cocrystals of Nefiracetam, a poor water-soluble nootropic compound. Three of which were obtained with the biocompatible cocrystallization agents citric acid, oxalic acid, and zinc chloride. These latter have been fully structurally and physically characterized and the solubility, dissolution rate, and stability were compared to that of the initial Active Pharmaceutical Ingredient (API).
doi:10.3390/pharmaceutics12070653 pmid:32660115 pmcid:PMC7408141 fatcat:ab7koh6rszfzbenvxaknzxmcki

Case report. Bijzonder recidief in de nier van een primair oesofaguscarcinoom

Tamara J. Oderkerk, Wouter M. H. Van der Sanden, Laurent M. C. L. Fossion
2018 Tijdschrift voor Urologie  
Samenvatting We presenteren een bijzondere casus van een recidief/metastase in de nier van een primair oesofaguscarcinoom. Trefwoorden tumorrecidief · oesofaguscarcinoom · renaalcelcarcinoom · metastase Case report. A surprising renal involvement as tumor recurrence of a primary esophageal carcinoma Abstract We present a case of a surprising renal involvement as tumor recurrence of a primary esophageal carcinoma.
doi:10.1007/s13629-018-00211-0 fatcat:slwelinomzayfh72lrq5qxry6u

3-Dimensional density profiles in edge plasma simulations for ICRF heating

Wouter Tierens, Jonathan Jacquot, Wei Zhang, Jean-Marie Noterdaeme, Volodymyr Bobkov, Laurent Colas, J. Hillairet
2017 EPJ Web of Conferences  
In this paper we discuss improvements made to two codes for the simulation of ICRF waves in edge plasmas: SSWICH-SW, which self-consistently models the interplay between sheath physics and radiofrequency waves (the slow wave), and RAPLICASOL, a Finite Element solver for Maxwell's equations in the cold plasma approximation. We have extended both to be able to handle 3D plasma density profiles. A comparison between a 1D and a 3D simulation reveals that the density profile dimensionality has a
more » ... tively small effect on E at the aperture, but a large effect on the sheath potential at the antenna limiters EPJ Web of Conferences 157, 03053 (2017)
doi:10.1051/epjconf/201715703053 fatcat:y2loexv2lzd45gzghykjz45sqa

Compartmentalization of integrin α6β4 signaling in lipid rafts

Laurent Gagnoux-Palacios, Michael Dans, Wouter van't Hof, Agnese Mariotti, Angela Pepe, Guerrino Meneguzzi, Marilyn D. Resh, Filippo G. Giancotti
2003 Journal of Cell Biology  
doi:10.1083/jcb.200305006 pmid:14517202 pmcid:PMC2173954 fatcat:e2knl7bwkjdthfjq6u7hwgfr3i

Effects of propofol and sevoflurane on hepatic blood flow: a randomized controlled trial

Jurgen van Limmen, Piet Wyffels, Frederik Berrevoet, Aude Vanlander, Laurent Coeman, Patrick Wouters, Stefan De Hert, Luc De Baerdemaeker
2020 BMC Anesthesiology  
Maintaining adequate perioperative hepatic blood flow (HBF) supply is essential for preservation of postoperative normal liver function. Propofol and sevoflurane affect arterial and portal HBF. Previous studies have suggested that propofol increases total HBF, primarily by increasing portal HBF, while sevoflurane has only minimal effect on total HBF. Primary objective was to compare the effect of propofol (group P) and sevoflurane (group S) on arterial, portal and total HBF and on the caval and
more » ... portal vein pressure during major abdominal surgery. The study was performed in patients undergoing pancreaticoduodenectomy because - in contrast to hepatic surgical procedures - this is a standardized surgical procedure without potential anticipated severe hemodynamic disturbances, and it allows direct access to the hepatic blood vessels. Patients were randomized according to the type of anesthetic drug used. For both groups, Bispectral Index (BIS) monitoring was used to monitor depth of anesthesia. All patients received goal-directed hemodynamic therapy (GDHT) guided by the transpulmonary thermodilution technique. Hemodynamic data were measured, recorded and guided by Pulsioflex™. Arterial, portal and total HBF were measured directly, using ultrasound transit time flow measurements (TTFM) and were related to hemodynamic variables. Eighteen patients were included. There was no significant difference between groups in arterial, portal and total HBF. As a result of the GDHT, pre-set hemodynamic targets were obtained in both groups, but MAP was significantly lower in group S (p = 0.01). In order to obtain these pre-set hemodynamic targets, group S necessitated a significantly higher need for vasopressor support (p < 0.01). Hepatic blood flow was similar under a propofol-based and a sevoflurane-based anesthetic regimen. Related to the application of GDHT, pre-set hemodynamic goals were maintained in both groups, but sevoflurane-anaesthetized patients had a significantly higher need for vasopressor support. Study protocol number is AGO/2017/002 - EC/2017/0164. EudraCT number is 2017-000071-90., NCT03772106 , Registered 4/12/2018, retrospective registered.
doi:10.1186/s12871-020-01150-3 pmid:32962657 pmcid:PMC7507611 fatcat:4wmrvd5yk5hjjamhxiq4w7a6wa

Modeling total and polarized reflectances of ice clouds: evaluation by means of POLDER and ATSR-2 measurements

Wouter H. Knap, Laurent C.- Labonnote, Gérard Brogniez, Piet Stammes
2005 Applied Optics  
Four ice-crystal models are tested by use of ice-cloud reflectances derived from Along Track Scanning Radiometer-2 (ATSR-2) and Polarization and Directionality of Earth's Reflectances (POLDER) radiance measurements. The analysis is based on dual-view ATSR-2 total reflectances of tropical cirrus and POLDER global-scale total and polarized reflectances of ice clouds at as many as 14 viewing directions. Adequate simulations of ATSR-2 total reflectances at 0.865 m are obtained with model clouds
more » ... isting of moderately distorted imperfect hexagonal monocrystals (IMPs). The optically thickest clouds ͑ Ͼ ϳ16͒ in the selected case tend to be better simulated by use of pure hexagonal monocrystals (PHMs). POLDER total reflectances at 0.670 m are best simulated with columnar or platelike IMPs or columnar inhomogeneous hexagonal monocrystals (IHMs). Less-favorable simulations are obtained for platelike IHMs and polycrystals (POLYs). Inadequate simulations of POLDER total and polarized reflectances are obtained for model clouds consisting of PHMs. Better simulations of the POLDER polarized reflectances at 0.865 m are obtained with IMPs, IHMs, or POLYs, although POLYs produce polarized reflectances that are systematically lower than most of the measurements. The best simulations of the polarized reflectance for the ice-crystal models assumed in this study are obtained for model clouds consisting of columnar IMPs or IHMs.
doi:10.1364/ao.44.004060 pmid:16004054 fatcat:jbkz4vhunnd7tdyjg5osevnylq

Life cycle assessment integration into energy system models: An application for Power-to-Methane in the EU

Herib Blanco, Victor Codina, Alexis Laurent, Wouter Nijs, François Maréchal, André Faaij
2020 Applied Energy  
Alexis Laurent acknowledges the funding received from the European Union's Horizon 2020 research and innovation program under grant agreement 691739 -REEEM (Role of technologies in an Energy Efficient  ... 
doi:10.1016/j.apenergy.2019.114160 fatcat:b42kiv5pbzgrxllxownsqybzky

Repeatability and predictive value of lactate threshold concepts in endurance sports

Jules A. A. C. Heuberger, Pim Gal, Frederik E. Stuurman, Wouter A. S. de Muinck Keizer, Yuri Mejia Miranda, Adam F. Cohen, Laurent Mourot
2018 PLoS ONE  
Introduction Blood lactate concentration rises exponentially during graded exercise when muscles produce more lactate than the body can remove, and the blood lactate-related thresholds are parameters based on this curve used to evaluate performance level and help athletes optimize training. Many different concepts of describing such a threshold have been published. This study aims to compare concepts for their repeatability and predictive properties of endurance performance. Methods Forty-eight
more » ... well-trained male cyclists aged 18-50 performed 5 maximal graded exercise tests each separated by two weeks. Blood lactate-related thresholds were calculated using eight different representative concepts. Repeatability of each concept was assessed using Cronbach's alpha and intra-subject CV and predictive value with 45 minute time trial tests and a road race to the top of Mont Ventoux was evaluated using Pearson correlations. Results Repeatability of all concepts was good to excellent (Cronbach's alpha of 0.89-0.96), intrasubject CVs were low with 3.4-8.1%. Predictive value for performance in the time trial tests and road race showed significant correlations ranging from 0.65-0.94 and 0.53-0.76, respectively. Conclusion All evaluated concepts performed adequate, but there were differences between concepts. One concept had both the highest repeatability and the highest predictability of cycling performance, and is therefore recommended to be used: the Dmax modified method. As an easier to apply alternative, the lactate threshold with a fixed value of 4 mmol/L could be used as it performed almost as well. Materials and methods Study design and participants Blood lactate curve data in this paper were generated in a previously published study. [12] Briefly, the study was a double-blind, randomized, placebo controlled, parallel, single centre trial to evaluate the effects of recombinant human erythropoietin (rHuEPO) in forty-eight healthy male cyclists aged 18 to 50. Informed consent was obtained from all individual Lactate threshold concepts in endurance exercise PLOS ONE |
doi:10.1371/journal.pone.0206846 fatcat:c3onv6ev45fvbaer7upkcrwkz4

Reynolds number effect on the velocity increment skewness in isotropic turbulence

Wouter J. T. Bos, Laurent Chevillard, Julian F. Scott, Robert Rubinstein
2012 Physics of Fluids  
Second and third order longitudinal structure functions and wavenumber spectra of isotropic turbulence are computed using the EDQNM model and compared to results of the multifractal formalism. At the highest Reynolds number available in windtunnel experiments, R_λ=2500, both the multifractal model and EDQNM give power-law corrections to the inertial range scaling of the velocity increment skewness. For EDQNM, this correction is a finite Reynolds number effect, whereas for the multifractal
more » ... ism it is an intermittency correction that persists at any high Reynolds number. Furthermore, the two approaches yield realistic behavior of second and third order statistics of the velocity fluctuations in the dissipative and near-dissipative ranges. Similarities and differences are highlighted, in particular the Reynolds number dependence.
doi:10.1063/1.3678338 fatcat:34ioti6qlfcopk53o5si26ykcu

Slab-geometry surface waves on steep gradients and the origin of related numerical issues in a variety of ICRF codes

Wouter Tierens, Laurent Colas, EUROfusion MST1 Team
2021 Journal of Plasma Physics  
In the ion cyclotron range of frequencies, electromagnetic surface waves are physically relevant for wave–filament interactions, parasitic edge losses and sheath–plasma waves. They are also important numerically, where non-physical surface waves may occur as side effects of slab-geometry approximations. We give new, completely general, mathematical techniques to construct dispersion relations for electromagnetic surface waves between any two media, isotropic or anisotropic, and first-order
more » ... ctions for when the material interface is steep but continuous. We discuss numerical issues (localized non-convergence, undesired power generation) that arise in numerical calculations due to the presence of surface waves.
doi:10.1017/s002237782100074x fatcat:mpjaah6fzfb5lm5a3cjbynlvte

A Vision for the Next Generation Platform-as-a-Service

Steven Van Rossem, Bessem Sayadi, Laurent Roullet, Angelos Mimidis, Michele Paolino, Paul Veitch, Bela Berde, Ignacio Labrador, Aurora Ramos, Wouter Tavernier, Eder Ollora, Jose Soler
2018 2018 IEEE 5G World Forum (5GWF)  
In an increasingly interconnected world, new opportunities for telecom-based services are emerging. Innovative applications profit from cloud versatility and scalability, but require a platform to combine the optimized 5G network fabric with the advancements in the domain of cloud computing, Software Defined Networking (SDN) and Network Function Virtualization (NFV). In this multi-domain context, we find that available service platforms are lagging, because they tend to be tightly coupled to a
more » ... onstrained set of technologies. In practice, we need the flexibility to deploy different microservices over a heterogeneous range of infrastructure types, aggregating various virtualization, orchestration and control mechanisms. Moreover, the integration of the service requires collaboration among a wide mix of actors (e.g. developers, operators, hardware/software vendors, infrastructure/service providers or vertical integrators). We propose a next-generation Platform-asa-Service (NGPaaS), devised as a modular framework for the development and operation of network services, while targeting a high degree of both customization and automation. The presented architecture is built around a workflow-based orchestrator which coordinates custom-built tasks across a tailored group of specialized infrastructure or platforms. We also explain how NGPaaS enhances DevOps-principles, to achieve a more efficient integration process across the many isolated administrative domains in the modern telco landscape. Keywords-NFV ; SDN; 5G; PaaS Architecture; DevOps; Devfor-Operations high modularity/microservice based high level of virtualization implementation characteristics Capex + Lock-in (vendor, technology) Time-to-market testing, communication overhead cost (dev, deployment, opex) optimal PaaS configuration default PaaS features monolithic, hardware-based Fig. 1 . The PaaS architecture is microservice-based, where the right design achieves the optimal trade-off.
doi:10.1109/5gwf.2018.8516972 dblp:conf/5gwf/RossemSRMPVBLRT18 fatcat:cmo7vdyb7zdgplvyzjgu7hwbuq

Semi-Supervised Approach for Recovering Traceability Links in Complex Systems

Emma Effa Bella, Marie-Pierre Gervais, Reda Bendraou, Laurent Wouters, Ali Koudri
2018 2018 23rd International Conference on Engineering of Complex Computer Systems (ICECCS)  
Building a complex system requires the collaboration of different stakeholders. They work together to model the system keeping in mind the requirements described in specification documents. This complexity induces a large volume of requirements and models, i.e., artefacts that will be subject to frequent changes during the project lifetime. Since the artefacts are correlated with each other's, each change has to be rigorously propagated. Identifying traceability links between system's artefacts
more » ... is then a critical step to reach this goal. In Information Retrieval domain, many approaches have been already proposed to cope with traceability issues. Their main drawback is they introduce an important amount of false positive links making the traceability links validation phase time consuming and error-prone. In this paper, we propose an approach that identifies traceability links with a reduced amount of false positive links ranging from 20% to 30% while raising the amount of true links identified up to 70%. The approach consists of three main steps: 1) we measure syntactical and semantic similarities between pairs of artefacts by combining the use of four major Information Retrieval techniques; 2) using these similarity measures, we identify the most likely true and false links and we build the so called training data set; 3) this training data set and the four IR techniques are used as input of a predictive model in order to classify between true and false links leading ultimately to a reduced amount of false positives. The output is given in the form of a confidence measure that will help the modeller validating the traceability links. We evaluated our approach using four well-known public case studies. Each one comes with a clear identification of true traceability links which allowed us to compare with the outcome of our approach and validate its effectiveness.
doi:10.1109/iceccs2018.2018.00030 dblp:conf/iceccs/BellaGBWK18 fatcat:ch3q37tjz5chzpvistld2vmd5y
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