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Determination of thermal stratification and turbulence of the atmospheric surface layer over various types of terrain by optical scintillometry / Alexandra Weiss (2002)
Titre : Determination of thermal stratification and turbulence of the atmospheric surface layer over various types of terrain by optical scintillometry Type de document : Thèse/HDR Auteurs : Alexandra Weiss, Auteur Editeur : Zurich : Institut für Geodäsie und Photogrammetrie IGP - ETH Année de publication : 2002 Collection : IGP Mitteilungen, ISSN 0252-9335 num. 075 Importance : 152 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-906467-36-8 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Atmosphère
[Termes IGN] atmosphère terrestre
[Termes IGN] capteur optique
[Termes IGN] rayonnement électromagnétique
[Termes IGN] rayonnement solaire
[Termes IGN] réfraction atmosphérique
[Termes IGN] scintillation
[Termes IGN] turbulenceRésumé : (Auteur) Thermal stratification and turbulence in the atmospheric surface layer cause refraction and scintillation of an optical beam. On the one hand, such atmospherically induced effects are undesirable in many applications which are based on optical wave propagation through the atmospheric boundary layer. Such examples are found in many applications of terrestrial optical surveying. On the other hand, such atmospherically induced effects can be used to derive various meteorological parameters. Based on these consideration the present work deals with the determination of thermal stratification and turbulence of the atmospheric surface layer over different types of terrain by optical scintillometry.
First, in this study a method is introduced and experimentally verified to derive correction values for precise terrestrial geodetic measurements. For highly precise optical direction and distance measurements, such corrections require lineaveraged temperature or refractive index gradients. Secondly, this study investigates how precisely lineaveraged turbulence parameters can be derived in the atmospheric surface layer by scintillometry and whether their derivation deepens our understanding of the structure of the atmospheric surface layer, especially over nonhomogeneous terrain. Here, the main focus lies in the investigation of the accuracy of the turbulent sensible heat and momentum fluxes, and the dissipation rate of turbulent kinetic energy, which are of grave importance for many meteorological applications. This work is based on various field experiments conducted with a socalled displacedbeam scintillometer under different atmospheric conditions. The experimental sites varied from homogeneous and flat terrain to flat, nonhomogeneous terrain up to slanted, nonhomogeneous terrain in an alpine valley. For validation of the method, additional meteorological measurement techniques are used and are considered in the data analysis, such as eddycorrelation measurements with sonic anemometerthermometers and Krypton hygrometers, and temperature profile measurements with Pt 1000 sensors.
The derivation of the thermal stratification from the scintillation method is especially dependent on the accuracy of the derived turbulent sensible heat flux. In the scope of this study, satisfactory accuracy of the derived turbulent sensible heat fluxes is obtained, even for nonhomogeneous terrain. It is shown that the presented method is applicable for deriving, lineaveraged refraction correction values over various types of terrain and for different atmospheric conditions with a good temporal resolution. This result is confirmed by comparisons with local temperature profile measurements. The linfitations of this method are discussed on the basis of the experimental datasets. For instance, under neutral conditions, with weak thermal turbulence, the derivation of accurate values of the turbulent momentum flux can be problematic with this method. However, in this work it is shown that the scintillation method gives accurate values under many atmospheric conditions including the turbulent momentum flux and for several other turbulence parameters. On the basis of the field experiments, new insights into the turbulence structure of the surface layer can be achieved by scintillometry, even over nonhomogeneous terrain. In this context the turbulent structure in an alpine valley is analysed and described under various boundary layer features.Numéro de notice : 15052 Affiliation des auteurs : non IGN Nature : Thèse étrangère En ligne : http://dx.doi.org/10.3929/ethz-a-004283039 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=55054 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 15052-01 47.50 Livre Centre de documentation En réserve M-103 Disponible Env-KPI, environnemental key performance indicators / S. Chesneau (2002)
Titre : Env-KPI, environnemental key performance indicators Type de document : Mémoire Auteurs : S. Chesneau, Auteur Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2002 Importance : 58 p. Format : 21 x 30 cm Note générale : Bibliographie
Mémoire de mastère spécialisé de la conférence des grandes écoles en architecture des systèmes d'information géographique (modèles d'applications)Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] émission de gaz
[Termes IGN] gaz
[Termes IGN] hydrocarbure
[Termes IGN] image radar
[Termes IGN] indicateur
[Termes IGN] navigation aérienne
[Termes IGN] performance
[Termes IGN] pollution atmosphérique
[Termes IGN] trajectographie (positionnement)Index. décimale : MASIG Ex mastère spécialisé Architecture des SIG Résumé : (Auteur) Commercial flights that are forced to follow non-optimal routes and profiles are estimated to produce between 6 and 12% more emissions than if they were allowed to fly 'direct' routes between their departure and destination airports. An increase in fuel consumption means an increase in gaseous emissions - C02, H20, S0x, NOx, FIC, Benzene, CO. The purpose of this study is to compare pollution from real European airplane traffic with that from simulated traffic, where all routes would be direct. In the context of "Sustainable aviation", this study examines the concept of "environmental capacity" for the next twenty years. It sets out to complement the work previously carried out for the Performance Review Report 4 (PRR4), that used radar and flight plan data collected over Maastricht Area. In this study, the recording area was extended to four additional European zones and the comparison was made using existing and newly developed Environmental Key Performance Indicators.
This study was divided into three parts :
1. Distance Analysis : Radar tracks provided by ATM suRveillance Tracker And Server system (ARTAS) were visualized in ArcView8, and compared by their lengths to the corresponding great circle distance.
2. Fuel Bum Analysis : Radar tracks were linked to Flight Plans using Aircraft Modelling Capacity (AMOC) Simulator, to identify the Type of Aircraft, and the departure and destination airports. AMOC also delivered direct routes corresponding to each correlated radar track. This preparation of the data allowed to use Advanced Emission Model 3 (AEM 3), a in-house tool that calculates fuel bum and emissions. The fuel consumption and related emissions were analysed for both direct and radar tracks using Environmental Key Performance Indicators.
3. Airport Pair Analysis: A more specific study was carried on between the Netherlands and Italy. It allowed a comparison between city pair radar routes, and the assessment of the influence of military zones on the studied traffic.
All these calculated Environmental Key Performance Indicators concerning aviation emissions will be integrated into the next Performance Review Report 5 (PRR5).Numéro de notice : 13077 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Mémoire masters divers Organisme de stage : Eurocontrol ; European Organisation for the Safety of Air Navigation Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=49877 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13077-01 MASIG Livre Centre de documentation En réserve Mezzanine Disponible Analysis of refraction influences in geodesy using image processing and turbulence models / Philipp Flach (2001)
Titre : Analysis of refraction influences in geodesy using image processing and turbulence models Type de document : Thèse/HDR Auteurs : Philipp Flach, Auteur Editeur : Zurich : Schweizerischen Geodatischen Kommission / Commission Géodésique Suisse Année de publication : 2001 Collection : Geodätisch-Geophysikalische Arbeiten in der Schweiz, ISSN 0257-1722 num. 63 Importance : 175 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-908440-05-5 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie
[Termes IGN] analyse spectrale
[Termes IGN] détecteur à transfert de charge
[Termes IGN] filtre de Wiener
[Termes IGN] instrument de géodésie
[Termes IGN] instrumentation Leica
[Termes IGN] méthode des moindres carrés
[Termes IGN] modèle atmosphérique
[Termes IGN] réfraction atmosphérique
[Termes IGN] spectre électromagnétique
[Termes IGN] traitement d'image
[Termes IGN] turbulence
[Termes IGN] variance
[Termes IGN] vidéothéodoliteIndex. décimale : 30.03 Instruments de géodésie Résumé : (Auteur) The propagation path of light in the atmosphere is influenced by inhomogeneities of the refractive index. These refraction effects deteriorate the accuracy of the direction and distance measurements in geodetic applications. As illustrated by two examples in this report, the refraction effects cannot be accurately corrected up to now and, therefore, solutions must be provided which can be implemented into geodetic instruments. The presented approach is based on the determination of the temperature gradient being the decisive influential parameter for angular refraction effects.
In the atmosphere, temperature gradients are related to turbulent thermal exchange processes such as the turbulent sensible heat flux. In order to describe atmospheric turbulence, the applied statistical approach uses the method of spectral analysis which states that the atmospheric turbulent velocity field can be thought to consist of many eddies of different densities. This energy spectrum of turbulence can be modelled using the structure constant of refractive index CJ and the inner scale 10 of turbulence. If these two structure parameters are measured, the temperature gradient is derived from dimensionless profile functions using the so-called Monin-Obukhov similarity description. Hereby, the fact should be kept in mind, that the Monin-Obukhov similarity description and the energy spectrum of turbulence are only valid for vertical temperature gradient profiles in the atmospheric boundary layer.
This research work investigates the determination of the required structure parameter Cn and lo by means of image sensors which can be built into geodetic instruments. To derive the structure parameters CJ and 10 from the acquired image data, the application of appropriate image processing techniques is examined. The evaluation concept is based on angle-of-arrival fluctuations and intensity fluctuations. Angle-of-arrival fluctuations are perceived as high-frequency motions of image patterns grabbed by the sensor, and intensity fluctuations are related to the temporal variation of the gray values of the pixels. As presented in this report, these two effects of optical turbulence can be used to determine the structure parameter Cn and lo. For this purpose, image processing techniques must parameterize both angle-of-arrival fluctuations and intensity fluctuations. Within this research work, the angle-of-arrival fluctuations are modelled by the variance óx characterizing the shifting of image patterns which are located using edge detection algorithms. The intensity fluctuations are modelled by the variance óx characterizing the temporal intensity spectrum of the incoming light beam. In the scope of this research work, the variance óx is provided using digital filter techniques such as the Wiener filter or least-squares template matching.
In order to validate this concept, the video theodolite Leica TM3000V and a digital line scan camera Basler L120 are used as two different imaging systems to acquire image data during various practical field experiments. These field experiments revealed a partial good agreement between the structure parameter CJ and lo obtained by the image sensors and the ones obtained by a reference system (scintillometer). Basically, the method presented here is appropriate to reduce the refraction influence. A decisive advantage of this method is based on the fact that additional sensors are not necessary (except for the image sensors which are built into the instrument). However, as the exemplary comparison of temperature gradients shows at the end of the report, further research work in the scope of the atmospheric boundary layer is still necessary.Numéro de notice : 13062 Affiliation des auteurs : non IGN Autre URL associée : http://dx.doi.org/10.3929/ethz-a-004045114 Thématique : POSITIONNEMENT Nature : Thèse étrangère DOI : 10.3929/ethz-a-004045114 En ligne : https://www.sgc.ethz.ch/sgc-volumes/sgk-63.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54863 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13062-01 30.03 Livre Centre de documentation En réserve M-103 Disponible 13062-02 30.03 Livre Centre de documentation En réserve M-103 Disponible Couplage d'un logiciel de trajectographie et du SIG ARC-INFO / I. Koua (2001)
Titre : Couplage d'un logiciel de trajectographie et du SIG ARC-INFO Type de document : Mémoire Auteurs : I. Koua, Auteur Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2001 Importance : 70 p. Format : 21 x 30 cm Note générale : Bibliographie
Rapport de projet pluridisciplinaire, cycle des ingénieurs diplômes de l'ENSG 2e année (IT2)Langues : Français (fre) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] ArcInfo
[Termes IGN] effondrement de terrain
[Termes IGN] forêt tempérée
[Termes IGN] Fortran
[Termes IGN] risque naturel
[Termes IGN] trajectographie (positionnement)
[Termes IGN] Triangulated Irregular Network
[Termes IGN] triangulation de DelaunayIndex. décimale : PROJET Mémoires : Rapports de projet - stage des ingénieurs de 2e année Résumé : (Auteur) Après une présentation du projet replacé dans son environnement, des notions sur la triangulation, les chutes de blocs et la trajectographie sont exposées. Les phases d'analyse de l'existant et de la reformulation de la demande, inhérentes au concept même de projet sont ensuite présentées. Suit la réponse à la demande, c'est-à-dire les détails concernant le produit réalisé et les tests quant à sa validation. Les différents manuels utilisateurs et le code Fortran des programmes écrits figurent en annexe. Note de contenu : INTRODUCTION
I- PRESENTATION DU PROJET
1- DEFINITION DU PROJET
2-OBJECTIFS
II- CONTEXTE DU PROJET
1-ENVIRONNEMENT
2- PRESENTATION DES ACTEURS
3- ANALYSE SOCIO-ORGANISATIONNELLE
III- SYNTHESE BIBLIOGRAPHIQUE
1-TRIANGULATION DE DELAUNAY
2- FORETS ET CHUTES DE BLOCS
3-TRAJECTOGRAPHIE
4-SYNTHESE
IV- ANALYSE DE L'EXISTANT
V- REFORMULATION DE LA DEMANDE - PROPOSITIONS
VI- REALISATION DU PRODUIT
1- LE PROGRAMME TRIG
a-L'algorithme de WATSON
b-La programmation de TRIG
c-Les fichiers
2- LE PROGRAMME TRIG_ARC
a- Génération d'un MNT à partir du module TIN de ARC/INFO
b- Extraction de fichiers
c- La programmation de TRIG_ARC
d- Les fichiers
3- LA VISUALISATION DE LA TRAJECTOIRE CALCULEE
a- Le calcul de la trajectoire
b- La visualisation avec MATLAB
c- La visualisation avec ARC/INFO
4- INTEGRATION DES DONNEES 'SOL'
5-MODELISATION DES ARBRES
VII- TESTS-VALIDATION
1- VALIDITE DU PRODUIT
2- RESULTATS SUR UNE ZONE D'ETUDE
CONCLUSIONNuméro de notice : 13327 Affiliation des auteurs : non IGN Thématique : FORET/GEOMATIQUE Nature : Mémoire de projet pluridisciplinaire Organisme de stage : CEMAGREF de Grenoble Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=49908 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13327-01 PROJET Livre Centre de documentation Travaux d'élèves Disponible Dreidimensionale kinematische Modelle zur Analyse von Deformationen an Hängen / P. Rawiel (2001)
Titre : Dreidimensionale kinematische Modelle zur Analyse von Deformationen an Hängen Titre original : [Modèles cinématiques en 3D pour l'analyse des déformations] Type de document : Thèse/HDR Auteurs : P. Rawiel, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2001 Collection : DGK - C Sous-collection : Dissertationen num. 533 Importance : 95 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9572-4 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] Cinématique
[Termes IGN] courbe de Bézier
[Termes IGN] Déformation
[Termes IGN] déformation de surface
[Termes IGN] glacier
[Termes IGN] interpolation polynomiale
[Termes IGN] modèle de déformation tectonique
[Termes IGN] modèle numérique de surface
[Termes IGN] modélisation 3D
[Termes IGN] Ploynôme
[Termes IGN] quantité discrète
[Termes IGN] SuisseIndex. décimale : 30.60 Géodésie spatiale Résumé : (Auteur) In the present work methods for deformation analysis are developed, that allow the calculation of shifts, velocities and accelerations in any point of the object for any time. Furthermore, deformation measures, such as expansions, shearing strains and rotations in the infinitesimal environment of the points can be calculated.
The main problem consists in the implementation of a continuous body from geodetic measurements at discrete points, in order to be able to apply the theories of continuum mechanics. Therefore, one focus is put on the theoretical description of the kinematics of the continuum as well as on the theoretical discussion of some interpolation methods, which are suitable for a solution of the problem. In particular, monomials, Bernstein polynomials as well as the generalized Bernstein polynomials as basis functions for the interpolation with bivariate polynomials, tensor product Bezier surfaces as well as triangle Bezier surfaces are presented and compared.
The theoretical considerations are tested with example data records of the rock glacier Macun I. The results of the modelling of the continuum are presented in form of concrete numerical values and diagrams and are discussed. Suggestions on refined basic approaches for the model on the basis of new realizations are developed and interfaces for the extension of the models in order to allow the integration of additional hybrid data are pointed out.
Beyond that, possibilities are presented for a transition of the used kinematic models to the dynamic models.Numéro de notice : 27831 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=56454 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 27831-01 33.60 Livre Centre de documentation Photogrammétrie - Lasergrammétrie Disponible Evaluation d'un système de positionnement d'un véhicule sur route basé sur la fusion de données / E. Helou Helo (2001)PermalinkModélisation et estimation du frottement atmosphérique sur les satellites Spot2 et Spot3 dans le cadre du système DORIS / R. Garmier (2001)PermalinkSpace gravity spectroscopy - The sensitivity analysis of GPS-tracked satellite missions (case study CHAMP) / C. Schäfer (2001)PermalinkLa visualisation des données Greenstar / L. Dufy (2001)PermalinkLe point sur l'évolution des techniques de guidage utilisées aujourd'hui / C. Maraget in XYZ, n° 84 (septembre - novembre 2000)PermalinkRemote sensing in the 21st century : economic and environmental applications / José Luis Casanova (2000)PermalinkLe chantier du centre technique Renault / M. Chevessier in XYZ, n° 80 (septembre - novembre 1999)PermalinkDORIS : orbite et localisation précises / Gilles Tavernier in Bulletin [Société Française de Photogrammétrie et Télédétection], n° 154 (Avril 1999)PermalinkRemote machine guidance by real-time kinematic GPS: improving work conditions, productivity and quality at construction sites / G. Hintzy in GIM international, vol 13 n° 3 (March 1999)PermalinkGravito-Viskoelastodynamik für verallgemeinerte Rheologienmit Anwendungen auf den Jupitermond lo und die Erde / K. Wieczerkowski (1999)Permalink