Results 31 to 40 of about 31,615 (293)

Estimation of leaf area and clumping indexes of crops with hemispherical photographs [PDF]

Agricultural and Forest Meteorology, 2008
Among many indirect approaches to retrieve effective leaf area index (LAI), hemispherical photography is now widely used by the scientific community in forestry applications. A recent software (CAN_EYE) is used to estimate effective and true LAI from unidirectional gap fractions measured in crops.
Demarez, Valérie, Duthoit, Sylvie, Baret, Frédéric, Weiss, Marie, Dedieu, Gérard   +4 more
openaire   +3 more sources

Extracting Leaf Area Index by Sunlit Foliage Component from Downward-Looking Digital Photography under Clear-Sky Conditions

Remote Sensing, 2015
The development of near-surface remote sensing requires the accurate extraction of leaf area index (LAI) from networked digital cameras under all illumination conditions.
Yelu Zeng, Jing Li, Qinhuo Liu, Ronghai Hu, Xihan Mu, Weiliang Fan, Baodong Xu, Gaofei Yin, Shengbiao Wu   +8 more
doaj   +1 more source

Generation of a 16 m/10-day fractional vegetation cover product over China based on Chinese GaoFen-1 observations: method and validation

International Journal of Digital Earth, 2023
As China has recently launched the GaoFen-1 satellite (GF-1) carrying on the wide-field view (WFV) sensor, it is a challenging task to make full use of its observations to produce the fractional vegetation cover (FVC).
Jing Zhao, Jing Li, Qinhuo Liu, Baodong Xu, Xihan Mu, Yadong Dong   +5 more
doaj   +1 more source

Canada-wide foliage clumping index mapping from multiangular POLDER measurements

Canadian Journal of Remote Sensing, 2005
In this paper, vegetation canopy structural information is retrieved over Canada from multiangular Advanced Earth Observing Satellite (ADEOS-1) polarization and directionality of the earth's reflectance (POLDER) data based on canopy radiative transfer simulations using the Five-Scale model.
Sylvain G Leblanc, Jing M Chen, H. Peter White, Rasim Latifovic, Roselyne Lacaze, Jean-Louis Roujean   +5 more
openaire   +1 more source

Non-thermal radio emission from O-type stars. IV. Cyg OB2 No. 8A [PDF]

, 2010
We study the non-thermal radio emission of the binary Cyg OB2 No. 8A, to see if it is variable and if that variability is locked to the orbital phase. We investigate if the synchrotron emission generated in the colliding-wind region of this binary can ...
Adam, Antokhin, Bell, Bell, Bieging, Blandford, Blomme, Blomme, Chen, Contreras, D. Volpi, De Becker, De Becker, De Becker, Dougherty, Dougherty, Dougherty, Dworetsky, Eichler, G. Rauw, Ginzburg, Jones, Kramer, Leitherer, Lemaster, M. De Becker, Nazé, Owocki, Owocki, Parkin, Pittard, Pittard, Pittard, Pittard, Pittard, Pittard, Puls, Puls, R. Blomme, Reimer, Schlickeiser, Schnerr, Schulte, Shaviv, Van Loo, Van Loo, Van Loo, Waldron, Weber, Wright   +49 more
core   +2 more sources

Retrieving the Leaf Area Index of Dense and Highly Clumped Moso Bamboo Canopies from Sentinel-2 MSI Data

Remote Sensing
The effects of leaf clumping on leaf area index (LAI, m2·m−2) retrieval have been proved by several studies. For dense and highly clumped Moso bamboo canopies, LAI is usually retrieved using the SAIL-series models that do not account for leaf clumping ...
Weiliang Fan, Jun Wu, Guang Zheng, Qian Zhang, Xiaojun Xu, Huaqiang Du, Mengxiang Zheng, Kexin Zhang, Feng Zhang   +8 more
doaj   +1 more source

Improving the Retrieval of Forest Canopy Chlorophyll Content From MERIS Dataset by Introducing the Vegetation Clumping Index

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2021
The accurate retrieval of canopy chlorophyll content (CCC) is essential to the effective monitoring of forest productivity, and environmental stress. However, the clumping index (CI), a vital canopy structural parameter, affects inaccurate remote sensing
Qi Sun, Quanjun Jiao, Liangyun Liu, Xinjie Liu, Xiaojin Qian, Xiao Zhang, Bing Zhang   +6 more
doaj   +1 more source

Neutralino Annihilations and the Gas Temperature in the Dark Ages

, 2007
Assuming the dark matter is made entirely from neutralinos, we re-visit the role of their annihilation on the temperature of diffuse gas in the high redshift universe. We consider neutralinos of particle mass 36 GeV and 100 GeV, respectively.
Abel, Adi Nusser, Albuquerque, Baltz, Baltz, Benson, Berezhiani, Bromm, Chen, Chuzhoy, Colafrancesco, Diemand, Diemand, Ellis, Felten, Field, Furlanetto, Green, Gunn, Haardt, Hansen, Jungman, Kamionkowski, Kasuya, Kasuya, Mapelli, Padmanabhan, Peebles, Peebles, Pieri, Pieri, Pierpaoli, Press, Ripamonti, Rudaz, Sciama, Shull, Silk, Spergel, Stecker, Tasitsiomi, Thomas, Turner, Ullio, Zacharia Myers, Zhang   +45 more
core   +2 more sources

Constraints on First-Light Ionizing Sources from Optical Depth of the Cosmic Microwave Background [PDF]

, 2008
We examine the constraints on high-redshift star formation, ultraviolet and X-ray pre-ionization, and the epoch of reionization at redshift z_r, inferred from the recent WMAP-5 measurement, tau_e = 0.084 +/- 0.016, of the electron scattering optical ...
Aparna Venkatesan, Begelman M. C., J. Michael Shull, Kodaira K., Ricotti M.   +4 more
core   +3 more sources

Digital Cover Photography for Estimating Leaf Area Index (LAI) in Apple Trees Using a Variable Light Extinction Coefficient

Sensors, 2015
Leaf area index (LAI) is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards.
Carlos Poblete-Echeverría, Sigfredo Fuentes, Samuel Ortega-Farias, Jaime Gonzalez-Talice, Jose Antonio Yuri   +4 more
doaj   +1 more source