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Ixion : logiciel d'orbitographie et d'échantillonnage

Michel Capderou
2017 La Météorologie  
I xion est un logiciel d'orbitographie et d'échantillonnage (Capderou, 2012 (Capderou, , 2014 . On appelle orbitographie l'étude des orbites des satellites.  ...  On trouvera toutes les informations sur ces deux logiciels dans deux livres abondamment illustrés (Capderou, 2012 (Capderou, , 2014 .  ... 
doi:10.4267/2042/62162 fatcat:cxddoizwynfubbpamwn4istnty

Les orbites des satellites météorologiques

Michel Capderou
2017 La Météorologie  
Les satellites météorologiques sont étudiés ici du point de vue de leur orbite. On présente en détail les deux principaux types d'orbite utilisés : l'orbite géostationnaire (GEO), qui fournit au satellite un point de vue fixe de la Terre sur l'équateur terrestre mais très éloigné ; l'orbite plus basse (LEO), qui permet d'observer, grâce à la propriété d'héliosynchronisme, avec de bonnes conditions d'éclairement solaire. Nous terminons par d'autres types d'orbites utilisées plus récemment.
more » ... ct Satellite orbits for meteorology Meteorological satellites are studied in this article from the point of view of their orbit. The two most common orbit types are explained: the geostationary orbit (GEO), which provides the satellite with a fixed point of view of the Earth on the terrestrial equator, but is very remote; the lower orbit (LEO), which makes it possible to observe Earth scenes with good conditions of solar illumination, thanks to the property of Sunsynchronism. We end with other types of orbit more recently used.
doi:10.4267/2042/62172 fatcat:mxg3eq6r6nf7vpx2yuyh65gmm4

Geometry of the Ellipse [chapter]

Michel Capderou
2014 Handbook of Satellite Orbits  
The purpose of this article is to provide the results of a research on the use of specific artefacts (two different ellipsographs) for the learning of Mathematics, specifically in Analytic Geometry on the topic of Ellipse. It was implemented one activity for each one of the artefact, by means of the use of working sheets that guided the students for tem to build the formal concept of Ellipse, answering to the corresponding questions in each activity as well as manipulating the ellipsograph. All
more » ... with the aim to facilitate to the students the understanding and learning of the mathematic concepts. Abstract El propósito de éste articulo, es dar a conocer los resultados de una investigación relacionada con el uso de artefactos concretos (dos elipsógrafos distintos) para el aprendizaje de las Matemáticas, específicamente en Geometría Analítica con el tema de Elipse. Se implementaron una actividad por cada uno de los artefactos, a través del uso de hojas de trabajo las cuales guían a los estudiantes para que ellos puedan construir el concepto formal de Elipse, respondiendo las preguntas correspondientes en cada actividad así como manipulando el elipsógrafo en cuestión. Lo anterior con el objetivo de facilitar la comprensión y el aprendizaje de conceptos matemáticos por parte de los alumnos.
doi:10.1007/978-3-319-03416-4_1 fatcat:5lmoehy5y5eslpt6xbd4gmqabu

Megha-Tropiques : un satellite hydrométéorologique franco-indien

Michel DESBOIS, Michel CAPDEROU, Laurence EYMARD, Remy ROCA, Nicolas VILTARD, Michel VIOLLIER, Nadia Karouche
2007 La Météorologie  
Une première ébauche de document de spécifications de mission était alors écrite par Michel Rouzé et Michel Desbois : elle n'a été que légèrement modifiée depuis cette date.Au printemps 2003, le conseil  ...  Michel Rouzé, le représentant de la Direction des pro- grammes du Cnes, était remplacé par Vincent Cassé. La phase A était conclue en avril 2001.  ... 
doi:10.4267/2042/18185 fatcat:c22ysliac5be3axskzweupgl2q

True Along-Track Scan to Improve Radiation Budget Estimations

Michel Capderou, Michel Viollier
2006 Journal of Atmospheric and Oceanic Technology  
If the development of the terrestrial geopotental is continued at order m, the expression of ⍀ is more complex, with terms in J 2 2 , J 4 , J 6 , . . . , J m (Capderou 2005 ).  ...  This quantity, which is important in the study of recurrent orbits (Capderou 2005) , is defined by ϭ n ⍀ E Ϫ ⍀ . ͑8͒ Using , we thus obtain tan jЈ ϭ sin j Ϫ ͑1ր͒ cos cos j , ͑9͒ and rewriting j with Eq  ... 
doi:10.1175/jtech1907.1 fatcat:ezrv7l3u4vgq5iuoj4eal5bawi

Optimal orbits for Mars atmosphere remote sensing

Michel Capderou, François Forget
2004 Planetary and Space Science  
However, the principal cause of this £` ( ) ¥ ¤ § ¦ U ¤ ¤ ¡ Ẍ © 4 Y 6 % (3) The coefficient, here noted ¤ ¦ , is only function of ¢ ¡ , mass and radius ¤ of the planet (Capderou, 2002) .  ... 
doi:10.1016/j.pss.2004.03.006 fatcat:twatmmsyvrgk7hnw4qn2zppqba

Comparison of Echocardiography and CT for the Assessment of Aortic Stenosis Valve Area

Michel Habis, Andre Capderou, Said Ghostine, Jean-Francois Paul
2015 JACC Cardiovascular Imaging  
To our knowledge, this is the first report of followup OCT assessments in CTO lesions with BVS including subintimal scaffolding. Although the results herewith demonstrated are promising, we acknowledge that longer-term follow-up imaging evaluations would be able to provide further insights into the assessment of scaffold reabsorption, whereas physiological assessments would be able to test whether vasodilation capabilities are recovered in this setting. Further validation of our findings is
more » ... anted. Sarano M. Aortic valve area calculation of aortic stenosis by CT and Doppler echocardiography. J Am Coll Cardiol Img 2015;8:248-57. 2. Baumgartner H, Kratzer H, Helmreich G, Kuehn P. Determination of aortic valve area by Doppler echocardiography using the continuity equation: a critical evaluation. Clin Cardiol 1990;77:101-11. 3. Hamdan A, Guetta V, Konen, et al. Deformation dynamics and mechanical properties of the aortic annulus by 4-dimensional computed tomography. J Am Coll Cardiol 2012;59:119-27. 4. Clavel MA, Pibarot P, Messika-Zeitoun D, et al. Impact of aortic valve calcification, as measured by MDCT, on survival in patients with aortic stenosis. J Am Coll Cardiol 2014;64:1202-13. 5. Habis M, Daoud B, Roger VL, et al. Comparison of 64-slice computed tomography planimetry and Doppler echocardiography in the assessment of aortic valve stenosis. J Heart Valve Dis 2007;16:216-24. REPLY: Comparison of Echocardiography and CT for the Assessment of Aortic Stenosis Valve Area We appreciate the interest of Dr. Habis and colleagues in our study (1) and their contribution to this research area. In response to their first issue, there is indeed a difference in the elliptic shape of the left ventricular outflow tract (LVOT) between systole and diastole by multidetector computed tomography (MDCT). Although this shape change is statistically significant, the clinical significance of the difference is modest and would rarely change the grading of aortic stenosis (AS) severity by MDCT. Indeed, in our study the timing of LVOT planimetry between systole and diastole would affect LVOT area by 6% (between 2% and 14%), a finding consistent with the literature (1-3) and close to the variation observed by intraobserver and interobserver variability (2). Thus, the issue of systolic versus diastolic LVOT measurement does not affect our results notably, as reported in our paper (1). Planimetry of aortic valve area, as emphasized by Dr. Habis and colleagues, measures the geometric orifice area (GOA), not the effective orifice area (EOA), so differences between methods are expected. We agree that the theoretical interest of planimetered GOA by MDCT is linked to the hypothesis that MDCTplanimetered GOA may have superior reproducibility and reliability. Although the seminal work on CT 5. Clavel MA, Pibarot P, Messika-Zeitoun D, et al. Impact of aortic valve calcification, as measured by MDCT, on survival in patients with AS: results of an international registry study. J Am Coll Cardiol 2014;64: 1202-13.
doi:10.1016/j.jcmg.2015.04.017 pmid:26381772 fatcat:4v5ixzkgrrh6lmuywhqxqzpvzu

On the water and energy cycles in the Tropics

Rémy Roca, Jean-Claude Bergès, Hélène Brogniez, Michel Capderou, Philippe Chambon, Olivier Chomette, Sophie Cloché, Thomas Fiolleau, Isabelle Jobard, Julien Lémond, Mohamed Ly, Laurence Picon (+3 others)
2010 Comptes rendus Geoscience  
Special thanks to Michel Desbois for having initiated most of this scientific activity over the last 30 years.  ... 
doi:10.1016/j.crte.2010.01.003 fatcat:6v523r7ztzfjrfnfs2plirb5yy

Cell therapy to restore overloaded right ventricular function: Will the dream come true?

Virginie Lambert, André Capderou, Elodie Gouadon, Mohamed Ly, Emmanuel Le Bret, Philippe Jourdon, Jean-François Renaud, Michel Pucéat, Catherine Rucker-Martin
2013 Archives of Cardiovascular Diseases  
Background.-Despite the prevalence of right ventricular (RV) failure in congenital heart diseases, cell therapy applied to the right ventricle is poorly studied. Our aim was to evaluate in a large animal model of overloaded RV dysfunction such therapy using cardiac progenitors issued from human embryonic stem cells. Methods.-A model of combined (barometric and volumetric) overloaded RV dysfunction was created in piglets using a surgical procedure mimicking repaired tetralogy of Fallot. After 4
more » ... onths, cell therapy was surgically administrated using either multiple trans-epicardial injections of HUES-24 derived human cardiac progenitors into right ventricle myocardium or extracellular matrix hydrogel patches seeded with cardiac progenitors and sewn after a gentle abrasion on the free wall of the right ventricle. Myocardial function was measured 3 months after cell transplantation by conductance catheter technique using maximal elastance
doi:10.1016/j.acvd.2013.06.012 fatcat:24yqtjiizferfoh5xi2ofezn7u

Acute Myocardial Infarction Early Viability Assessment by 64-Slice Computed Tomography Immediately After Coronary Angiography

Michel Habis, André Capderou, Saïd Ghostine, Béatrice Daoud, Christophe Caussin, Jean-Yves Riou, Philippe Brenot, Claude Yves Angel, Bernard Lancelin, Jean-François Paul
2007 Journal of the American College of Cardiology  
Objectives Early evaluation of myocardial viability in acute myocardial infarction is useful to guide therapy. Therefore, we assessed 64-slice computed tomography (CT) immediately after coronary angiography in this setting. From the Departments of *Cardiology, †Physiology, and ‡Radiology, Centre Chirurgical Marie Lannelongue, Le Plessis Robinson, France. Manuscript
doi:10.1016/j.jacc.2006.12.032 pmid:17367662 fatcat:4udhr4bse5bwhpzunwzcq4wjpu

Non-Invasive Detection of Coronary Artery Disease in Patients With Left Bundle Branch Block Using 64-Slice Computed Tomography

Saïd Ghostine, Christophe Caussin, Béatrice Daoud, Michel Habis, Eric Perrier, David Pesenti-Rossi, Anne Sigal-Cinqualbre, Claude-Yves Angel, Bernard Lancelin, André Capderou, Jean-François Paul
2006 Journal of the American College of Cardiology  
OBJECTIVES The goal of this study was to evaluate the diagnostic accuracy of 64-slice computed tomography (CT) to identify coronary artery disease (CAD) in patients with complete left bundle branch block (LBBB). BACKGROUND Left bundle branch block increases risk of cardiac mortality, and prognosis is primarily determined by the underlying coronary disease. Non-invasive stress tests have limited performance, and conventional coronary angiography (CCA) is usually required. METHODS Sixty-six
more » ... utive patients with complete LBBB and sinus rhythm admitted for CCA were enrolled. Computed tomography was performed 3 Ϯ 3.9 days before CCA. The accuracy of 64-slice CT to detect significant stenosis (Ͼ50% lumen narrowing) was compared with quantitative coronary angiography. All segments were analyzed regardless of image quality from coronary calcification or motion artifacts. Results were analyzed by patient and by coronary segment (990) using the American Heart Association 15-segment model. RESULTS Lower heart rates were associated with improved image quality. Computed tomography correctly identified 35 of 37 (95%) patients without significant stenosis and 28 of 29 (97%) patients with significant stenosis on CCA. Computed tomography correctly assessed 68 of 94 (72%) significant stenosis. Overall, accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 64-slice CT for identifying CAD by patient was 95%, 97%, 95%, 93%, and 97%, respectively, and by segment was 97%, 72%, 99%, 91%, and 97%, respectively. CONCLUSIONS In a routine clinical practice, 64-slice CT detects with excellent accuracy a significant CAD in patients with complete LBBB. A normal CT in this clinical setting is a robust tool to act as a filter and avoid invasive diagnostic procedures. (J Am Coll Cardiol 2006;48:1929 -34)
doi:10.1016/j.jacc.2006.04.103 pmid:17112979 fatcat:cmmwx5w7cvgnlfymedv6x4rvi4

0245: Cell therapy to restore overloaded right ventricular function: First promising results using human cardiac progenitors seeded in a patch on the epicardium

Catherine Rucker-Martin, Elodie Gouadon, Philippe Jourdon, André Capderou, Mohamed Ly, David Luu, Emmanuel Le Bret, Reda Kasdy, Jean-François Renaud, Emre Belli, Michel Pucéat, Virginie Lambert
2014 Archives of Cardiovascular Diseases Supplements  
Mineralocorticoid Receptor Antagonists (MRA) have proven their cardioprotective effects in individuals with chronic heart failure (CHF) by minimizing the cardiovascular damages caused by the excessive aldosterone production observed in those patients. Metabolic syndrome (MetS) that represents one of the major risk factors for CHF has been also reported to be associated with increased aldosterone levels and MR activation and may contribute in that way to the pathogenesis of HF. Thus, we
more » ... zed that targeting the MetS by the early antagonism of the MR may prevent or delay the subsequent transition to CHF in a rat model of HF associated or not with a MetS. MRA Eplerenone (100 mg/kg/day) or placebo was administrated to 1.5 month-old obese and lean Spontaneously Hypertensive Heart Failure male rats (SHHF cp/cp and SHHF +/+ respectively) for a period of 11 months. Animal metabolic and cardiac parameters were regularly monitored during the protocol. When compared to the SHHF +/+ , MetS rats induces of mortality of 30% in SHHF cp/cp group that was completely prevented by the preventive treatment with Eplerenone. Indeed, SHHF cp/cp developed over time a massive obesity, dyslipidemia and insulin resistance. Echocardiograms showed an accelerated transition to cardiac dysfunction evidenced by left ventricular hypertrophy (LVH), a decreased relaxation and contractile properties of the myocardium as well as LV dilatation. MRA, prevented rats' body weight gain (-10%), dyslipidemia (-50%) and enhanced adiponectinemia (+50%). Independently of a blood pressure decrease, cardiac parameters of Eple-SHHF cp/cp rats were preserved compared to SHHF cp/cp : LV diameter (9.9±0.14 vs 11.4±0.13 mm, respectively), LV mass (1760±72 vs 2195±73 mg), ejection fraction (70±1 vs 59±1%), isovolumic relaxation time (30±1 vs 22±1 ms) and E/A ratio (1.7±0.1 vs 3±0.3). Altogether, our data demonstrated that administration of eplerenone at the very early stages of MetS delayed their progression to CHF and prevented mortality. The beneficial cardioprotective effects were obtained via a mechanism independent of blood pressure lowering.
doi:10.1016/s1878-6480(14)71398-9 fatcat:lusgorxe3vbt3p536dm7fx75tu

Using kinematic GNSS data to assess the accuracy and precision of the TanDEM-X DEM resampled at 1 m resolution over the western Corinth Gulf, Greece

Pierre Briole, Simon Bufferal, Dimitar Dimitrov, Elias Panagiotis, Cyril Journeau, Antonio Avallone, Konstantinos Kamberos, Michel Capderou, Alexandre Nercessian
2021 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
We assess the accuracy and the precision of the TanDEM-X digital elevation model (DEM) of the western Gulf of Corinth, Greece. We use a dense set of accurate ground coordinates obtained by kinematic Global Navigation Satellite Systems (GNSS) observations. Between 2001 and 2019, 148 surveys were made, at a 1 s sampling rate, along highways, roads, and tracks, with a total traveled distance of ∼25 000 km. The data are processed with the online Canadian Spatial Reference System precise point
more » ... oning software. From the output files, we select 885 252 coordinates from epochs with theoretical uncertainty below 0.1 m in horizontal and 0.2 m in vertical. Using specific calibration surveys, we estimate the mean vertical accuracy of the GNSS coordinates at 0.2 m. Resampling the DEM by a factor of 10 allows one to compare it with the GNSS in pixels of metric size, smaller than the width of the roads, even the small trails. The best fit is obtained by shifting the DEM by 0.47 ± 0.03 m upward, 0.10 ± 0.1 m westward, and 0.36 ± 0.1 m southward. Those values are 20 times below the nominal resolution of the DEM. Once the shift is corrected, the root mean square deviation between TanDEM-X DEM and GNSS elevations is 1.125 m. In forest and urban areas, the shift between the DEM
doi:10.1109/jstars.2021.3055399 fatcat:oyceq56yrrci7bzgsz7thlqz6a

Observing Mars from Areostationary Orbit: Benefits and Applications

Luca Montabone, Nicholas Heavens, Jose L. Alvarellos, Michael Aye, Alessandra Babuscia, Nathan Barba, J. Michael Battalio, Tanguy Bertrand, Bruce Cantor, Michel Capderou, Matthew Chojnacki, Shannon M. Curry (+28 others)
2021 Bulletin of the AAS  
doi:10.3847/25c2cfeb.0cdca220 fatcat:rkj4waptrnfn5f7qucxgxbizd4

Vient de paraître

Jean-Pierre JAVELLE
2012 La Météorologie  
Par Michel Capderou. Springer-Verlag France, Paris, 2012, 862 p. 75 €. En 2003, Michel Capderou avait publié Satellites, orbites et missions.  ... 
doi:10.4267/2042/47249 fatcat:kc2mhhatj5edjpz3mb5gk2uhmq
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