Browsing Complete repository Arts & humanities   Archaeology   Art & art history   Classical & oriental studies   History   Languages & linguistics   Literature   Performing arts   Philosophy & ethics   Religion & theology   Multidisciplinary, general & others Business & economic sciences   Accounting & auditing   Production, distribution & supply chain management   Finance   General management & organizational theory   Human resources management   Management information systems   Marketing   Strategy & innovation   Quantitative methods in economics & management   General economics & history of economic thought   International economics   Macroeconomics & monetary economics   Microeconomics   Economic systems & public economics   Social economics   Special economic topics (health, labor, transportation…)   Multidisciplinary, general & others Engineering, computing & technology   Aerospace & aeronautics engineering   Architecture   Chemical engineering   Civil engineering   Computer science   Electrical & electronics engineering   Energy   Geological, petroleum & mining engineering   Materials science & engineering   Mechanical engineering   Multidisciplinary, general & others Human health sciences   Alternative medicine   Anesthesia & intensive care   Cardiovascular & respiratory systems   Dentistry & oral medicine   Dermatology   Endocrinology, metabolism & nutrition   Forensic medicine   Gastroenterology & hepatology   General & internal medicine   Geriatrics   Hematology   Immunology & infectious disease   Laboratory medicine & medical technology   Neurology   Oncology   Ophthalmology   Orthopedics, rehabilitation & sports medicine   Otolaryngology   Pediatrics   Pharmacy, pharmacology & toxicology   Psychiatry   Public health, health care sciences & services   Radiology, nuclear medicine & imaging   Reproductive medicine (gynecology, andrology, obstetrics)   Rheumatology   Surgery   Urology & nephrology   Multidisciplinary, general & others Law, criminology & political science   Civil law   Criminal law & procedure   Criminology   Economic & commercial law   European & international law   Judicial law   Metalaw, Roman law, history of law & comparative law   Political science, public administration & international relations   Public law   Social law   Tax law   Multidisciplinary, general & others Life sciences   Agriculture & agronomy   Anatomy (cytology, histology, embryology...) & physiology   Animal production & animal husbandry   Aquatic sciences & oceanology   Biochemistry, biophysics & molecular biology   Biotechnology   Entomology & pest control   Environmental sciences & ecology   Food science   Genetics & genetic processes   Microbiology   Phytobiology (plant sciences, forestry, mycology...)   Veterinary medicine & animal health   Zoology   Multidisciplinary, general & others Physical, chemical, mathematical & earth Sciences   Chemistry   Earth sciences & physical geography   Mathematics   Physics   Space science, astronomy & astrophysics   Multidisciplinary, general & others Social & behavioral sciences, psychology   Animal psychology, ethology & psychobiology   Anthropology   Communication & mass media   Education & instruction   Human geography & demography   Library & information sciences   Neurosciences & behavior   Regional & inter-regional studies   Social work & social policy   Sociology & social sciences   Social, industrial & organizational psychology   Theoretical & cognitive psychology   Treatment & clinical psychology   Multidisciplinary, general & others      by title 0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z or enter first few letters:    OK Showing results 46326 to 46345 of 114413     2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322     Frequency of Solar-like Systems and of Ice and Gas Giants Beyond the Snow Line from High-magnification Microlensing Events in 2005-2008Gould, A.; Dong, Subo; Gaudi, B. S. et alin Astrophysical Journal (2010), 720We present the first measurement of the planet frequency beyond the "snow line," for the planet-to-star mass-ratio interval –4.5 < log q < –2, corresponding to the range of ice giants to gas giants. We ... [more ▼]We present the first measurement of the planet frequency beyond the "snow line," for the planet-to-star mass-ratio interval –4.5 < log q < –2, corresponding to the range of ice giants to gas giants. We find \endgraf\vbox{\begin{center}$\displaystyle{d^2 N{_{\rm pl}}\over d\log q\, d\log s} = (0.36\pm 0.15)\;{\rm dex}^{-2}$\end{center}}\noindentat the mean mass ratio q = 5 × 10 –4 with no discernible deviation from a flat (Öpik's law) distribution in log-projected separation s. The determination is based on a sample of six planets detected from intensive follow-up observations of high-magnification ( A>200) microlensing events during 2005-2008. The sampled host stars have a typical mass M host ~ 0.5 M sun [less ▲]Detailed reference viewed: 72 (8 ULg) Frequency of Solar-Like Systems and Planet Mass-Ratio Distribution Function Beyond the Snow Line from High-Magnification Microlensing EventsGould, A.; Dong, S.; Gaudi, B~S et alin Astrophysical Journal (2010), 720Detailed reference viewed: 20 (6 ULg) The frequency ratio method and the new multiperiodic gamma Doradus star HD 218427Rodríguez, E.; Amado, P. J.; Suárez, J. C. et alin Astronomy and Astrophysics (2006), 450Oscillations of gamma Dor-type were discovered in the star HD 218427 through simultaneous uvby photometric observations carried out in the year 2003. A few Hbeta-Crawford measurements were also collected ... [more ▼]Oscillations of gamma Dor-type were discovered in the star HD 218427 through simultaneous uvby photometric observations carried out in the year 2003. A few Hbeta-Crawford measurements were also collected for calibration purposes and they locate this star well inside the gamma Dor instability region. We find HD 218427 to be deficient in metals, similar to other well-defined gamma Dor stars, and discuss the possibility that it has a lambda Boo nature. We carried out frequency analysis for different filters, including the combined "vby" filter, and five frequencies were found as significant with periods ranging between 0.3 and 0.8 days. The recently-developed frequency ratio method is used in order to identify the excited modes. The results are consistent with an l=2 identification for all the modes and with high radial quantum numbers (nË 40) for the three main observed periodicities. The possibility of multiplet structures is also discussed. However, no consistency is found when using the time-dependent convection treatment to discriminate modes. This disagreement can be due to the large rotation velocity taking place in HD 218427 and, consequently, the significant coupling between the modes. [less ▲]Detailed reference viewed: 6 (0 ULg) Frequency, characteristics, and functions of future-oriented thoughts in daily lifeD'Argembeau, Arnaud ; Renaud, Olivier; Van der Linden, Martial in Applied Cognitive Psychology (2011), 25Detailed reference viewed: 71 (5 ULg) A Frequency-domain Approach to Subspace Identification of Nonlinear Systems, Application to Aerospace StructuresNoël, Jean-Philippe Doctoral thesis (2014)The construction of mathematical models from experimental data is an essential step in the design process of engineering systems. The different tasks involved in this activity, from the measurement and ... [more ▼]The construction of mathematical models from experimental data is an essential step in the design process of engineering systems. The different tasks involved in this activity, from the measurement and processing of data to the validation of the model, fall into the general field of system identification. In structural dynamics, the theoretical and experimental aspects of linear system identification have been successfully addressed since the early seventies, and mature analytical, computational and testing tools have emerged. Nonlinear system identification of vibrating structures has also enjoyed significant advances during the past few years. However, the common practice in industry is to ignore nonlinearities, arguably because their analysis is still regarded as impractical. The objective of this doctoral thesis is precisely to progress towards the development of a practical system identification methodology dedicated to real-life nonlinear structures. The first facet of the thesis is to introduce a nonlinear generalisation in the frequency domain of the so-called subspace identification methods. The proposed frequency-domain nonlinear subspace identification (FNSI) approach yields accurate models of large-scale systems comprising strong nonlinearities, closely-spaced modes and high damping. Because it can also estimate a large number of parameters while maintaining an acceptable computational burden, the second facet of this research is to investigate the utilisation of cubic splines as a very flexible means to model complex nonlinearities. Finally, the third facet of the present work is to derive nonlinear models with optimal statistical properties in the presence of measurement noise. This is achieved by embedding the FNSI method into the maximum likelihood identification framework. The scope of the identification and modelling tools developed in this thesis encompasses nonlinear structural systems originating from the various areas of vibration engineering, including the aerospace, mechanical or civil fields, amongst others. Throughout the dissertation, these tools are illustrated using numerical and experimental structures of increasing complexity, mainly related to aerospace applications. [less ▲]Detailed reference viewed: 89 (22 ULg) A Frequency-Domain Processor for Maximum Resolution and Quicklook Processing of Wide-Swath ASAR ImagesBarbier, Christian ; Piette, François; Renson, Luc et alin Proc. EUSAR'96 Conference (1996)Detailed reference viewed: 8 (1 ULg) A Frequency-Domain Processor for ScanSAR ImagesBarbier, Christian ; Rosello-Guasch, Josepin Preparing for the Future (1995), 5(4), 6-7Detailed reference viewed: 12 (2 ULg) Frequency-domain subspace identification for nonlinear mechanical systemsNoël, Jean-Philippe ; Kerschen, Gaëtan in Mechanical Systems & Signal Processing (2013), 40This paper introduces a new frequency-domain subspace-based method for the identification of nonlinear mechanical systems. The technique exploits frequency-domain data and interprets nonlinearities as ... [more ▼]This paper introduces a new frequency-domain subspace-based method for the identification of nonlinear mechanical systems. The technique exploits frequency-domain data and interprets nonlinearities as feedback forces exciting the underlying linear system. It is first demonstrated using two academic examples, namely a Duffing oscillator and a five-degree-of-freedom system comprising two nonlinearities. The identification of an experimental beam exhibiting geometrically nonlinear behaviour is then addressed. [less ▲]Detailed reference viewed: 30 (13 ULg) Frequency-domain subspace identification of nonlinear mechanical systemsNoël, Jean-Philippe ; Kerschen, Gaëtan in Proceedings of the 5th International Operational Modal Analysis Conference (2013, May)The objective of the present paper is to address the identification of a real-life strongly nonlinear space structure, the EADS-Astrium SmallSat spacecraft. To this end, a new nonlinear subspace ... [more ▼]The objective of the present paper is to address the identification of a real-life strongly nonlinear space structure, the EADS-Astrium SmallSat spacecraft. To this end, a new nonlinear subspace identification method formulated in the frequency domain is exploited, referred to as the FNSI method. The frequency response functions of the underlying linear spacecraft and the amplitudes of the nonlinear internal forces are estimated based on a periodic-random data set corrupted by noise. This application is challenging for several reasons, including high modal density, highly non-proportional damping and the non-smooth nature of the nonlinearities. [less ▲]Detailed reference viewed: 57 (7 ULg) Frequency-domain subspace identification of nonlinear mechanical systems - Application to a solar array structureNoël, Jean-Philippe ; Kerschen, Gaëtan ; Foltête, Emmanuel et alin Proceedings of the International Modal Analysis Conference (IMAC) XXXI (2013, February)The present paper addresses the experimental identification of a simplified realisation of a solar array structure in folded configuration. To this end, a nonlinear subspace identification technique ... [more ▼]The present paper addresses the experimental identification of a simplified realisation of a solar array structure in folded configuration. To this end, a nonlinear subspace identification technique formulated in the frequency domain, referred to as the FNSI method, is exploited. The frequency response functions of the underlying linear structure and the nonlinear coefficients are estimated by this approach. Nonlinearity is caused by impacts between adjacent panels and friction and gaps appearing in their clamping interfaces. This application is challenging for several reasons, which include high modal density and the complicated nature of the involved nonlinear mechanisms. [less ▲]Detailed reference viewed: 59 (8 ULg) La fréquentation des massifs forestiers à des fins récréatives et de détente pour la population wallonne et bruxelloiseColson, Vincent in Forêt Wallonne (2006), (81), 26-38Une enquête téléphonique menée auprès de 1 005 personnes habitant les régions bruxelloise et wallonne a tenté de caractériser le type de public qui se rend en forêt, les périodes recherchées ou encore les ... [more ▼]Une enquête téléphonique menée auprès de 1 005 personnes habitant les régions bruxelloise et wallonne a tenté de caractériser le type de public qui se rend en forêt, les périodes recherchées ou encore les activités pratiquées. Les destinations choisies et le consentement à payer pour ce type de loisir ont également été abordés. [less ▲]Detailed reference viewed: 87 (12 ULg) La fréquentation des massifs forestiers wallons: le public, ses activités et sa perception de la forêtColson, Vincent in Forêt Wallonne (2007), (87), 20-35Une enquête a été menée entre octobre 2005 et août 2006 au sein de quarante massifs forestiers afin de pouvoir dresser l’image la plus fidèle de la fréquentation de la forêt wallonne. Les questions posées ... [more ▼]Une enquête a été menée entre octobre 2005 et août 2006 au sein de quarante massifs forestiers afin de pouvoir dresser l’image la plus fidèle de la fréquentation de la forêt wallonne. Les questions posées ont permis de caractériser le profil du public, les activités pratiquées et la façon dont est perçue la forêt. [less ▲]Detailed reference viewed: 79 (7 ULg) La fréquentation des promenades balisées en forêt wallonne. Résultat d'une enquête menée avec la collaboration de huit organismes touristiques wallonsColson, Vincent in Les Echos du Tourisme (2006), (44), 7-8Dans le cadre d’une étude portant sur l’évaluation de la fonction récréative de la forêt wallonne, une enquête a été réalisée entre le 1er mai et le 7 novembre 2005 auprès des utilisateurs de cartes de ... [more ▼]Dans le cadre d’une étude portant sur l’évaluation de la fonction récréative de la forêt wallonne, une enquête a été réalisée entre le 1er mai et le 7 novembre 2005 auprès des utilisateurs de cartes de promenades de 8 organismes touristiques (Florenville, Spa, Saint-Hubert, Nassogne, Assesse, Viroinval, Lobbes et Villersla- Ville). Les personnes acquérant une carte de promenades étaient invitées à répondre à un questionnaire à renvoyer au moyen d’une enveloppe « port payé par le destinataire ». Malgré un faible taux de réponse (196 soit 6,3%), des informations intéressantes ont pu être obtenues sur le profil des promeneurs et sur leurs desiderata. Cet article reprend quelques-uns des principaux résultats obtenus. [less ▲]Detailed reference viewed: 62 (8 ULg) Frequently Relapsing Crohn's Disease Is Characterized by Persistent Elevation in Interleukin-6 and Soluble Interleukin-2 Receptor Serum Levels During RemissionVan Kemseke, Catherine ; Belaiche, Jacques ; Louis, Edouard in International Journal of Colorectal Disease (2000), 15(4), 206-10We examined immune and inflammatory activation during remission in patients with Crohn's disease who presented with various clinical profiles (prolonged remission vs. relapsing disease). Thirty-six ... [more ▼]We examined immune and inflammatory activation during remission in patients with Crohn's disease who presented with various clinical profiles (prolonged remission vs. relapsing disease). Thirty-six patients with at least 3 years' follow-up starting from a remission period were studied retrospectively. Relapses were defined by a retrospective calculation of the Crohn's disease activity index or by the clinical judgement of the physicians in charge of the patients. Disease course over the study period was assessed by the mean number of annual relapses. Analysis used measurements during remission of the following: erythrocytes sedimentation rate, relative lymphocytosis, acid alpha1-glycoprotein, interleukin-6 (IL-6), and soluble interleukin-2 receptor (sIL-2R) serum levels. During the study period 21 patients experienced at least one relapse and 15 did not. Mean serum levels of sIL-2R and mean relative lymphocytosis in remission significantly discriminated between relapsing and nonrelapsing patients. Only the mean sIL-2R serum level was selected by multivariate analysis, with a cutoff value of 82 pM/1 (sensitivity of 76% and specificity of 80%). The only features correlated with mean number of annual relapses in the relapsing patients were mean serum levels of sIL-2R (r=0.58, P=0.015) and IL-6 in remission (r=0.45, P=0.039). Multivariate analysis demonstrated statistical significance only for the mean serum level of IL-6 (P=0.014). In Crohn's disease the persistent elevation in sIL-2R serum levels during remission corresponds to chronic active disease, while high serum levels of IL-6 in these patients is associated with a high frequency of relapse. [less ▲]Detailed reference viewed: 31 (0 ULg) Frères et soeurs pour la vie? : Les relations fraternelles à l'épreuve du tempsFavart, Evelyne Book published by Cortext (2007)Detailed reference viewed: 310 (24 ULg) A fresh look on confidence markingLeclercq, Dieudonné ; De Brogniez, Philippe (1990)Detailed reference viewed: 23 (1 ULg) Fresnel rhombs as achromatic phase shifters for infrared nulling interferometryMawet, D.; Hanot, Charles ; Lenaers, C. et alin Optics Express (2007), 15We propose a new family of achromatic phase shifters for infrared nulling interferometry. These key optical components can be seen as optimized Fresnel rhombs, using the total internal reflection ... [more ▼]We propose a new family of achromatic phase shifters for infrared nulling interferometry. These key optical components can be seen as optimized Fresnel rhombs, using the total internal reflection phenomenon, modulated or not. The total internal reflection indeed comes with a phase shift between the polarization components of the incident light. We propose a solution to implement this vectorial phase shift between interferometer arms to provide the destructive interference process needed to disentangle highly contrasted objects from one another. We also show that, modulating the index transition at the total internal reflection interface allows compensating for the intrinsic material dispersion in order to make the subsequent phase shift achromatic over especially broad bands. The modulation can be induced by a thin film of a well-chosen material or a subwavelength grating whose structural parameters are thoroughly optimized. We present results from theoretical simulations! together with preliminary fabrication outcomes and measurements for a prototype in Zinc Selenide. [less ▲]Detailed reference viewed: 44 (9 ULg) Fresnel rhombs as achromatic phase shifters for infrared nulling interferometry: first experimental resultsHanot, Charles ; Mawet, D.; Loicq, Jerôme et alin Coulter, Daniel R (Ed.) "Techniques and Instrumentation for Detection of Exoplanets III" Proceedings of the SPIE, Volume 6693, Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (2007, September 01)One of the most critical units of nulling interferometers is the Achromatic Phase Shifter. The concept we propose here is based on optimized Fresnel rhombs, using the total internal reflection phenomenon ... [more ▼]One of the most critical units of nulling interferometers is the Achromatic Phase Shifter. The concept we propose here is based on optimized Fresnel rhombs, using the total internal reflection phenomenon, modulated or not. The total internal reflection induces a phase shift between the polarization components of the incident light. We present the principles, the current status of the prototype manufacturing and testing operations, as well as preliminary experiments on a ZnSe Fresnel rhomb in the visible that have led to a first error source assessment study. Thanks to these first experimental results using a simple polarimeter arrangement, we have identified the bulk scattering as being the main error source. Fortunately, we have experimentally verified that the scattering can be mitigated using spatial filters and does not decrease the phase shifting capabilities of the ZnSe Fresnel rhomb. [less ▲]Detailed reference viewed: 57 (7 ULg) Fret ferroviaire : vue prospectiveArda, Yasemin ; Nondonfaz, Robert Article for general public (2009)Livre blanc de la Commission Européenne. Faiblesses du transport ferroviaire de fret : interopérabilité, ferroutageDetailed reference viewed: 9 (2 ULg) Freud chez les didacticiens: de la gram-mère castratrice à l'inconscient grammaticalDefays, Jean-Marc Conference (2000, October)Detailed reference viewed: 28 (2 ULg)