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Gini coefficient predictions from airborne lidar remote sensing display the effect of management intensity on forest structure / Rubén Valbuena in Ecological indicators, vol 60 (January 2016)
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[article]
Titre : Gini coefficient predictions from airborne lidar remote sensing display the effect of management intensity on forest structure Type de document : Article/Communication Auteurs : Rubén Valbuena, Auteur ; Kalle Eerikäinen, Auteur ; Petteri Packalen, Auteur ; Matti Maltamo, Auteur Année de publication : 2016 Article en page(s) : pp 574 - 585 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse comparative
[Termes IGN] analyse diachronique
[Termes IGN] coefficient de Gini
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] Finlande
[Termes IGN] hauteur des arbres
[Termes IGN] parc naturel national
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] surveillance forestière
[Termes IGN] sylvicultureRésumé : (auteur) In this study, two forest sites located in Finland were compared by means of predictions of Gini coefficient (GC) obtained from airborne laser scanning (ALS). We discuss the potential of the proposed method for identifying differences in structural complexity in relation with the management history of forests. The first study site (2200 ha), the Koli National Park (NP), includes areas where human intervention was restricted after 1907, in addition to forests which were protected only after the 1990s. The second study site in the municipality of Kiihtelysvaara (800 ha) has been under intensive management. These are commercial forests which include areas with different types of ownership: a large estate owned by an industrial company together with smaller private properties. We observed that GC predictions may be used to evaluate the effects of management practice on forest structure. Conservation and commercial forests showed significant differences, with the old-protected area of Koli having the highest, and the most intensively managed area in Kiihtelysvaara the lowest GC values. The effect of management history was revealed, as the 1990s’ extensions of Koli NP were more similar to unprotected areas than to forests contained within the original borders of the 1907s’ state property. Yet, their conservation status for almost two decades has been sufficient for developing significant differences against the outside of the NP. In Kiihtelysvaara, we found significant differences in GC according to the type of ownership. Moreover, the ALS predictions of GC also detected differences near lakeshores, which are driven by limitations on logging governed by Finnish law. Estimating this indicator with ALS remote sensing allowed to observe its spatial distribution and to detect peculiarities which would otherwise be unavailable from field plot sampling. Consequently, the method presented appears to be well suited for monitoring the effects of management practice, as well as verifying its compliance with legal restrictions. Numéro de notice : A2016-338 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.ecolind.2015.08.001 En ligne : http://dx.doi.org/10.1016/j.ecolind.2015.08.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81022
in Ecological indicators > vol 60 (January 2016) . - pp 574 - 585[article]
Titre : Gravity field processing towards LL-SST satellite missions Type de document : Thèse/HDR Auteurs : Ilias Daras, Auteur ; Roland Pail, Directeur de thèse Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2016 Collection : DGK - C, ISSN 0065-5325 num. 770 Importance : 153 p. ISBN/ISSN/EAN : 978-3-7696-5182-9 Note générale : bibliographie
PhD DissertationLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] accéléromètre
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] crénelage
[Termes IGN] filtrage du bruit
[Termes IGN] gravimétrie spatiale
[Termes IGN] interféromètre au laser
[Termes IGN] poursuite de satellite
[Termes IGN] résidu
[Termes IGN] satellite d'observation de la TerreRésumé : (auteur) This study focuses on important aspects concerning gravity field processing of future LL-SST [Low-Low Satellite-to-Satellite Tracking] satellite missions. Closed-loop simulations taking into account error models of new generation instrument technology are used to estimate the gravity field accuracy that future missions could provide. Limiting factors are identified, and methods for their treatment are developed. The contribution of all error sources to the error budget is analyzed. It is shown that gravity field processing with double precision may be a limiting factor for exploiting the nm-level accuracy of a laser interferometer. An enhanced numerical precision processing scheme is proposed instead, where double and quadruple precision is used in different parts of the processing chain. It is demonstrated that processing with enhanced precision can efficiently handle laser measurements and take full advantage of their accuracy, while keeping the computational times within reasonable levels. However, error sources of considerably larger impact are expected to affect future missions, with the accelerometer instrument noise and temporal aliasing effects being the most significant ones. The effect of time-correlated noise such as the one present in accelerometer measurements, can be efficiently handled by frequency dependent data weighting. Residual time series that contain the effect of system errors and propagated accelerometer and laser noise, is considered as a noise realization with stationary stochastic properties. The weight matrix is constructed from the auto-correlation functions of these residuals. Applying the weight matrix to a noise case considering all error sources leads to reduction of the error level over the complete spectral bandwidth. Co-estimation of empirical accelerations does not show the same efficiency in reducing the propagated noise with the applied processing strategy. Temporal aliasing effects are reduced essentially by adding a second pair of satellites at an inclined orbit. Compared to a GRACE-type near-polar pair, such a Bender-type constellation delivers solutions with major improvements in terms of de-aliasing potential and recovery performance. When the integrated effect of all geophysical processes is recovered, the maximum spatial resolution of 11-day solutions can be increased from 715 to 315 km half-wavelength. A further reduction of temporal aliasing errors is possible by co-parameterizing low resolution gravity fields at short time intervals, together with the higher resolution gravity field which is sampled at a longer time interval. One day was found to be the optimal sampling period for reducing the error levels in the solutions. A uniform sampling at the co-parameterized short periods, is a prerequisite for an efficient reduction of aliasing errors. High frequency atmospheric signals are captured by daily solutions to a large extent. Hence co-parameterization at daily basis results in significant reduction of aliasing caused by their under-sampling. This enables future gravity satellite missions to deliver the complete spectrum of Earth's geophysical processes. The corresponding by-products of daily gravity field solutions are expected to be very useful to atmospheric science and open doors to new fields of application. Note de contenu : 1. Introduction
1.1. Background
1.2. Motivation and objectives of this study
1.3. Outline
2. Earth's gravity field determination form satellite observations
2.1. Pertubing forces acting on a satellite
2.2. Geopotential and its functionals
2.3. Dedicated gravity satellite missions
2.4. Concepts for future satellite gravity missions
3. Description of the simulation environment for the gravity fields recovery
3.1. Outline of the simulation environment
3.2. Coordinate and time systems
3.3. Simulation if the satellite orbits
3.4. Functional model
3.5. Formulation of the NEQ system
3.6. Solution of the NEQ system
4. Design aspects and error budget of future dedicated gravity satellite missions
4.1. Orbit design
4.2. Satellite formation flights
4.3. Selected orbits for the simulations
4.4. Science and mission requirements
4.5. Noise models for the performance of the instruments
4.6. Error budget analysis
7. Treatment of temporal aliasing effects
7.1. Temporal aliasing for NGGLs
7.2. Co-parameterization of low spatial resolution gravity fiels solutions at higher frequencies
7.3. Retrieval content of NGGM gravity fiels solutions
8. ConclusionsNuméro de notice : 19791 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Note de thèse : PhD Dissertation : Geodesy : Stuttgart : 2016 DOI : sans En ligne : http://nbn-resolving.de/urn:nbn:de:bvb:91-diss-20160211-1279854-1-3 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85011
Titre : Introduction to Statistics and Data Analysis : With Exercises, Solutions and Applications in R Type de document : Guide/Manuel Auteurs : Christian Heumann, Auteur ; Michael Schomaker, Auteur Editeur : Springer International Publishing Année de publication : 2016 Importance : 456 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-3-319-46162-5 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] coefficient de Gini
[Termes IGN] courbe de Lorenz
[Termes IGN] estimateur
[Termes IGN] probabilités
[Termes IGN] R (langage)
[Termes IGN] régression linéaire
[Termes IGN] variable aléatoireRésumé : (éditeur) This introductory statistics textbook conveys the essential concepts and tools needed to develop and nurture statistical thinking. It presents descriptive, inductive and explorative statistical methods and guides the reader through the process of quantitative data analysis. In the experimental sciences and interdisciplinary research, data analysis has become an integral part of any scientific study. Issues such as judging the credibility of data, analyzing the data, evaluating the reliability of the obtained results and finally drawing the correct and appropriate conclusions from the results are vital. The text is primarily intended for undergraduate students in disciplines like business administration, the social sciences, medicine, politics, macroeconomics, etc. It features a wealth of examples, exercises and solutions with computer code in the statistical programming language R as well as supplementary material that will enable the reader to quickly adapt all methods to their own applications. Note de contenu : 1- Descriptive Statistics
2- Probability Calculus
3- Inductive StatisticsNuméro de notice : 25822 Affiliation des auteurs : non IGN Thématique : INFORMATIQUE/MATHEMATIQUE Nature : Manuel En ligne : https://doi.org/10.1007/978-3-319-46162-5 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95097
Titre : Introduction to Time Series and Forecasting Type de document : Monographie Auteurs : Peter J. Brockwell, Auteur ; Richard A. Davis, Auteur Editeur : Springer International Publishing Année de publication : 2016 Importance : 425 p. Format : 21 x 28 cm ISBN/ISSN/EAN : 978-3-319-29854-2 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] analyse spectrale
[Termes IGN] calcul matriciel
[Termes IGN] matrice de covariance
[Termes IGN] méthode du maximum de vraisemblance (estimation)
[Termes IGN] modèle de simulation
[Termes IGN] modèle stochastique
[Termes IGN] série temporelle
[Termes IGN] variable aléatoireRésumé : (éditeur) This book is aimed at the reader who wishes to gain a working knowledge of time series and forecasting methods as applied to economics, engineering and the natural and social sciences. It assumes knowledge only of basic calculus, matrix algebra and elementary statistics. This third edition contains detailed instructions for the use of the professional version of the Windows-based computer package ITSM2000, now available as a free download from the Springer Extras website. The logic and tools of time series model-building are developed in detail. Numerous exercises are included and the software can be used to analyze and forecast data sets of the user's own choosing. The book can also be used in conjunction with other time series packages such as those included in R. The programs in ITSM2000 however are menu-driven and can be used with minimal investment of time in the computational details. The core of the book covers stationary processes, ARMA and ARIMA processes, multivariate time series and state-space models, with an optional chapter on spectral analysis. Many additional special topics are also covered. Note de contenu : 1- Introduction
2- Stationary Processes
3- ARMA Models
4- Spectral Analysis
5- Modeling and Forecasting with ARMA Processes
6- Nonstationary and Seasonal Time Series Models
7- Time Series Models for Financial Data
8- Multivariate Time Series
9- State-Space Models
10- Forecasting Techniques
11- Further TopicsNuméro de notice : 25750 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Monographie En ligne : https://link.springer.com/book/10.1007%2F978-3-319-29854-2 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94942 Investigating efficacy of robust M-estimation of deformation from observation differences / Krzysztof Nowel in Survey review, vol 48 n° 346 (January 2016)
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Titre : Investigating efficacy of robust M-estimation of deformation from observation differences Type de document : Article/Communication Auteurs : Krzysztof Nowel, Auteur Année de publication : 2016 Article en page(s) : pp 21 - 30 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] analyse de données
[Termes IGN] déformation géométrique
[Termes IGN] estimation statistique
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] méthode des moindres carrés
[Termes IGN] modèle stochastique
[Termes IGN] test de performanceRésumé : (auteur) In deformation analysis of geodetic control networks, it is important to know whether the estimated displacement value of a given point is the effect of displacement or only the effect of random measurement errors. The F-test of statistical significance is used to answer this question. This test is applied both in conventional deformation analysis (CDA) based on least square (LS) estimation and in deformation analysis based on robust M-estimation. Unfortunately, the F-test is strongly flawed in the latter case. As a consequence, its results are significantly different here than assumed/expected. This paper analyses how flawed the F-test is and proposes a new solution. First, the algorithm of the global and local F-tests was derived. It was then demonstrated that for deformation analysis based on robust M-estimation, this algorithm has theoretical flaws. Next, it was shown how these problems can be solved numerically. The basis of the solutions proposed involves the use of stochastic simulations and, more specifically, the Monte Carlo (MC) method. Moreover, it was noted that other statistical test problems which also occur in deformation analysis based on robust M-estimation can be solved using present-day computers. The numerical approach can be a good support here in the selection of the proper significance level as well as in the correct performance of the test sensitivity analysis. All theoretical discussions were verified on an example simulated control network. Numéro de notice : A2016-044 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1080/00396265.2015.1097585 En ligne : https://doi.org/10.1080/00396265.2015.1097585 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79637
in Survey review > vol 48 n° 346 (January 2016) . - pp 21 - 30[article]Landmark based localization: LBA refinement using MCMC-optimized projections of RJMCMC-extracted road marks / Bahman Soheilian (2016)
PermalinkLocalisation à base d’amers visuels : Cartographie et mise en correspondance de marquages au sol et intégration dans LBA / Bahman Soheilian (2016)
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PermalinkModelling forest canopy trends with on-demand spatial simulation / Gordon M. Green in International journal of geographical information science IJGIS, vol 30 n° 1-2 (January - February 2016)
PermalinkMultifractal analysis for multivariate data with application to remote sensing / Sébastien Combrexelle (2016)
PermalinkOn estimation of the diagonal elements of a sparse precision matrix / Samuel Balmand in Electronic Journal of Statistics, vol 10 n° 1 (January 2016)
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PermalinkPassive microwave remote sensing of soil moisture based on dynamic vegetation scattering properties for AMSR-E / Jinyang Du in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)
PermalinkPermalinkA probabilistic approach for InSAR time-series postprocessing / Ling Chang in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)
PermalinkPermalinkQualité des données géographiques : à propos de la propagation des incertitudes / Gilles Troispoux in Signature, n° 59 (janvier 2016)
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