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Spectral Invariant Provides a Practical Modeling Approach for Future Biophysical Variable Estimations

Yelu Zeng, Baodong Xu, Gaofei Yin, Shengbiao Wu, Guoqing Hu, Kai Yan, Bin Yang, Wanjuan Song, Jing Li
2018 Remote Sensing  
The sensitivity of NIRv to canopy structure and the robustness of NIRv to the soil background suggest NIRv is a promising index in future biophysical variable estimations with the support of the SIP model  ...  This paper presents a simple radiative transfer model based on spectral invariant properties (SIP).  ...  However, there are still several aspects of the spectral invariant that need to be improved for future biophysical variable estimations.  ... 
doi:10.3390/rs10101508 fatcat:cqdn7x44d5ftnav7sqhx7ql57u

Granger causality analysis of fMRI BOLD signals is invariant to hemodynamic convolution but not downsampling

Anil K. Seth, Paul Chorley, Lionel C. Barnett
2013 NeuroImage  
Our methods, which include detailed spiking neuronal models coupled to biophysically realistic hemodynamic observation models, provide an important 'analysis-agnostic' platform for evaluating functional  ...  Granger causality is a method for identifying directed functional connectivity based on time series analysis of precedence and predictability.  ...  Mortimer and Theresa Sackler Foundation (AKS and LB) via the Sackler Centre for Consciousness Science. We thank Adam Barrett for helpful discussions, and four reviewers for their insightful comments.  ... 
doi:10.1016/j.neuroimage.2012.09.049 pmid:23036449 fatcat:vlaklpkiuvglzamis4r2i5ygzm

Combining Satellite Remote Sensing Data with the FAO-56 Dual Approach for Water Use Mapping In Irrigated Wheat Fields of a Semi-Arid Region

Salah Er-Raki, Abdelghani Chehbouni, Benoit Duchemin
2010 Remote Sensing  
The aim of this study was to combine the FAO-56 dual approach and remotely-sensed data for mapping water use (ET c ) in irrigated wheat crops of a semi-arid region.  ...  crop biophysical parameters which were used in conjunction with FAO-56 dual source approach.  ...  Additional funding was provided by AUF ('the Action de Recherche du Réseau Télédétection de l'Agence Universitaire de la Francophonie') through 2092 RR 915 contract.  ... 
doi:10.3390/rs2010375 fatcat:5cpfcosvibcspfyex5xxucoj7i

Exploitation of SAR and Optical Sentinel Data to Detect Rice Crop and Estimate Seasonal Dynamics of Leaf Area Index

Manuel Campos-Taberner, Francisco García-Haro, Gustau Camps-Valls, Gonçal Grau-Muedra, Francesco Nutini, Lorenzo Busetto, Dimitrios Katsantonis, Dimitris Stavrakoudis, Chara Minakou, Luca Gatti, Massimo Barbieri, Francesco Holecz (+2 others)
2017 Remote Sensing  
On the other hand, non-parametric algorithms estimate biophysical variables using a training database containing pairs of the biophysical parameter and the associated spectral data [22] .  ...  However, crop models require information on soil, meteorological variable, crop parameters and management practices, which are not always available or practical to be obtained in a spatially distributed  ...  This kind of information provided by LAI estimates at such a resolution is indeed very useful for rice crop users and modelers.  ... 
doi:10.3390/rs9030248 fatcat:2v6g3wfey5dhveeuuc7wv67dxy

Mapping Biophysical Variables From Solar and Thermal Infrared Remote Sensing: Focus on Agricultural Landscapes With Spatial Heterogeneity

Frederic Jacob, Marie Weiss
2014 IEEE Geoscience and Remote Sensing Letters  
This letter closes a Special Stream that focuses on spatial heterogeneity when mapping biophysical variables over agricultural landscape from solar and thermal infrared remote sensing.  ...  We propose an overview of the highlights from prior research, we report the main results of the Special Stream, and we discuss future directions.  ...  Bottom-up approaches aim to estimate biophysical variables over a given extent by accounting for spatial heterogeneity within this extent.  ... 
doi:10.1109/lgrs.2014.2313592 fatcat:56vvmtwykbgftp3uog7ndlunba

Remote Sensing of Grassland Biophysical Parameters in the Context of the Sentinel-2 Satellite Mission

Karolina Sakowska, Radoslaw Juszczak, Damiano Gianelle
2016 Journal of Sensors  
Two models using Sentinel-2 simulated data (linear regression-vegetation indices (VIs) approach and multiple regression (MR) reflectance approach) were tested to estimate vegetation biophysical parameters  ...  To assess whether the use of full solar spectrum reflectance data is able to provide an added value in CCC and GFAPAR estimation accuracy, a third model based on partial least squares regression (PLSR)  ...  Acknowledgments The authors would like to acknowledge Mauro Cavagna and Roberto Zampedri for the ASD-WhiteRef system and Phenocam installation and maintenance in the field and Luca Zulini for sharing the  ... 
doi:10.1155/2016/4612809 fatcat:uuuebjgdfzgfhdspop4rus4nvi

Remote Sensing of Forest Biophysical Structure Using Mixture Decomposition and Geometric Reflectance Models

Forrest G. Hall, Yosio E. Shimabukuro, Karl F. Huemmrich
1995 Ecological Applications  
(NDVI), does not provide a useful measure of these biophysical characteristics.  ...  and toward a two-step process, in which (1) stand-level reflectance is approximated in terrns of linear combinations of reflectance-invariant, spectrally distinct components (spectral end members) and  ...  If true, these two factors would provide an alternate approach to estimating canopy biophysical characteristics for an overwhelming portion of the boreal ecosystem.  ... 
doi:10.2307/2269350 fatcat:hybserqe3ng47ggsnh625iwdti

Water productivity mapping using remote sensing data of various resolutions to support "more crop per drop"

Prasad S. Thenkabail
2009 Journal of Applied Remote Sensing  
The spectro-biophysical models were developed using IRS and Quickbird satellite data for wet biomass, dry biomass, leaf area index, and grain yield for 5 crops: (a) cotton, (b) maize, (c) winter wheat,  ...  Crop-specific productivity maps were developed by applying the best spectro-biophysical models for the respective delineated crop types.  ...  The result clearly shows the reliability of SSEB as a simple yet efficient approach for ET fraction estimation.  ... 
doi:10.1117/1.3257643 fatcat:6mcv3a4ngve7beppj36q3zpxwe

Empirical test of the spectral invariants theory using imaging spectroscopy data from a coniferous forest

Petr Lukeš, Miina Rautiainen, Pauline Stenberg, Zbyněk Malenovský
2011 International Journal of Applied Earth Observation and Geoinformation  
The spectral invariants theory presents an alternative approach for modeling canopy scattering in remote sensing applications.  ...  In this paper, we evaluate a method to retrieve two canopy spectral invariants, the recollision probability and the escape factor, for a coniferous forest using imaging spectroscopy data from multiangular  ...  Acknowledgements We thank Ivana Tomášková for information on Bílý Kříž forest stand variables, Jan Hanuš for AISA image data processing, and Lucie Homolová with Lucia Yanez Rausell for preprocessing of  ... 
doi:10.1016/j.jag.2011.04.003 fatcat:tis5cbz25fdahia23xtj4fhx4q

Light detection and ranging and hyperspectral data for estimation of forest biomass: a review

Qixia Man, Pinliang Dong, Huadong Guo, Guang Liu, Runhe Shi
2014 Journal of Applied Remote Sensing  
A review on the status of hyperspectral data, LiDAR data, and the fusion of these two data sources for forest biomass estimation in the last decade is provided.  ...  A summary of previous research on LiDAR-hyperspectral fusion for forest biomass estimation is valuable for further improvement of biomass estimation methods.  ...  The authors would like to thank anonymous reviewers for their helpful comments and suggestions.  ... 
doi:10.1117/1.jrs.8.081598 fatcat:hdvyjfwl3jbrflvrk5lko2xj4u

Characterization of pasture biophysical properties and the impact of grazing intensity using remotely sensed data

Izaya Numata, Dar A. Roberts, Oliver A. Chadwick, Josh Schimel, Fernando R. Sampaio, Francisco C. Leonidas, João V. Soares
2007 Remote Sensing of Environment  
A conceptual model was built for pasture biophysical change using three fractions, i.e., NPV, Shade and GV to characterize possible pasture degradation processes in Rondônia.  ...  For grazed pastures under dry conditions, the Normalized Difference Infrared Index (NDII5 and NDII7), had higher correlations with the biophysical measures than the Normalized Difference Vegetation Index  ...  Greg Asner, for their invaluable comments and suggestions.  ... 
doi:10.1016/j.rse.2007.01.013 fatcat:tn37bhlp2zavpc2v4tlsqaaara

LiDAR Utility for Natural Resource Managers

Andrew Thomas Hudak, Jeffrey Scott Evans, Alistair Matthew Stuart Smith
2009 Remote Sensing  
This review provides a cross-section of studies, many recent, that demonstrate the relevance of LiDAR across a suite of terrestrial natural resource disciplines including forestry, fire and fuels, ecology  ...  We anticipate that interest in and reliance upon LiDAR for natural resource management, both alone and in concert with other remote sensing data, will continue to rapidly expand for the foreseeable future  ...  Acknowledgements Partial support for this research came from the Sustainable Forestry component of Agenda 2020, a joint effort of USDA Forest Service Research and Development and the American Forest and  ... 
doi:10.3390/rs1040934 fatcat:wb3topr5qfenfo53xomgemw23y

DYNAMIC RETRIEVAL OF OLIVE TREE PROPERTIES USING BAYESIAN MODEL AND SENTINEL-2 IMAGES

Hana Abdelmoula, Abdelaziz Kallel, Jean-Louis Roujean, Jean-philippe Gastellu
2021 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
The goal of this study is to provide a fine detection and monitoring of olive orchard trees over large areas to anticipate any damage.  ...  As backward model, we developed an original technique based on the Markov Chain Monte Carlo (MCMC) method that has the advantage of being able to model sensor noise and account for spatial and temporal  ...  For more information, see https://creativecommons.org/licenses/by/4.0/ This article has been accepted for publication in a future issue of this journal, but has not been fully edited.  ... 
doi:10.1109/jstars.2021.3110313 fatcat:zuonvmtdvfcodd5kpbahfsegyu

Application of two regression-based methods to estimate the effects of partial harvest on forest structure using Landsat data

Sean P. Healey, Zhiqiang Yang, Warren B. Cohen, D. John Pierce
2006 Remote Sensing of Environment  
The second approach, which we called "direct change modeling" (DCM), involves modeling forest structure changes as a single term using re-measured inventory data and spectral differences from corresponding  ...  In a leave-one-out cross-validation process, DCM-derived estimates of harvest intensity had lower root mean square errors than SMD for both relative basal area change and relative cover change.  ...  Acknowledgements The authors are grateful for the financial and logistical support of WDNR and WDFW, and particularly acknowledge the expertise of Brian Cosentino and Shelly Snyder of WDFW.  ... 
doi:10.1016/j.rse.2005.12.006 fatcat:zmmmsvot6jbmzp7qiqu36te7de

Analytic measures for quantification of arousal from spontaneous skin conductance fluctuations

Dominik R. Bach, Karl J. Friston, Raymond J. Dolan
2010 International Journal of Psychophysiology  
Here, we derive a simple measure of sympathetic arousal, using a convolution model of how sudomotor bursting causes fluctuations in skin conductivity.  ...  We demonstrate the validity of this measure in relation to finite impulse response models, and show that it is a better predictor of autonomic arousal, relative to conventional measures.  ...  Gisela Erdmann who provided SCR data from her laboratory for re-analysis.  ... 
doi:10.1016/j.ijpsycho.2010.01.011 pmid:20144665 pmcid:PMC2877802 fatcat:nupxjoe6tne43i7fnjoqkgmzdu
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