Results 261 to 270 of about 432,356 (303)

AFRI — aerosol free vegetation index

Remote Sensing of Environment, 2001
Abstract Aircraft measurements using a field spectrometer over variety of ground surfaces in Israel reveals that under clear sky conditions, the shortwave infrared (SWIR) spectral bands around 1.6 and 2.1 μm are highly correlated with the visible — blue, green, and red — spectral bands. Empirical linear relationships, such as ρ 0.469 =0.25 ρ 2.1 ;
Arnon Karnieli, Yoram J. Kaufman, Lorraine Remer, Andrew Wald   +3 more
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Monitoring monthly soil moisture conditions in China with temperature vegetation dryness indexes based on an enhanced vegetation index and normalized difference vegetation index

Theoretical and Applied Climatology, 2020
Soil moisture is a key land surface parameter that reflects conditions of drought in agricultural areas, such that variations in soil moisture significantly impact agricultural production. At a large spatial scale, soil moisture can be indicated using the temperature vegetation drought index (TVDI), which is based on soil moisture monitoring.
Huichao Zhao, Yi Li, Xinguo Chen, Haoran Wang, Ning Yao, Fenggui Liu   +5 more
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Flooding Identification by Vegetation Index

2020
In this chapter, flooding identification by vegetation index was conducted by using SAR images and multispectral images in order to obtain the flooding period of the study area.
Chunxiang Cao, Min Xu, Patcharin Kamsing, Sornkitja Boonprong, Peera Yomwan, Apitach Saokarn   +5 more
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Directional vegetation index and its effects on normalized-difference-vegetation-index-based agricultural applications

SPIE Proceedings, 2006
The directional normalized difference vegetation index (NDVI) was calculated by using field measured spectral data of the winter wheat canopies at the crop different growth and development stages. In the principal plane, the hotspot and directional NDVI were analyzed.
Jun-hui Chen, Peng-xin Wang, Wei Sun, Li-ping Ling   +3 more
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Microwave polarization index for monitoring vegetation growth

IEEE Transactions on Geoscience and Remote Sensing, 1988
It is known that microwave emission for soil is partially polarized, whereas the polarization degree of radiation from crops is either very small or equal to zero. The effect of vegetation on the polarized emission from the soil is analyzed by means of a model based on the radiative transfer theory.
Paloscia S, Pampaloni P
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Calculating the vegetation index faster

Remote Sensing of Environment, 1990
The NIR versus red 'infrared percentage vegetation index', NIR/(NIR + Red), is functionally and linearly equivalent to the normalized difference vegetation index, (NIR-Red)/(NIR + Red). Advantageously, it is both computationally faster and never negative.
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Fractional vegetation cover estimation by using multi-angle vegetation index

Remote Sensing of Environment, 2018
Abstract The vegetation index-based (VI-based) mixture model is widely used to derive green fractional vegetation cover (FVC) from remotely sensed data. Two critical parameters of the model are the vegetation index values of fully-vegetated and bare soil pixels (denoted Vx and Vn hereafter). These are commonly empirically set according to spatial and/
Xihan Mu, Wanjuan Song, Zhan Gao, Tim R. McVicar, Randall J. Donohue, Guangjian Yan   +5 more
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A new Remote Sensing-based vegetation water stress index: -Temperature Vegetation Water Stress Index (TVWSI)

2020
<p>Remote sensing techniques are widely used to evaluate the biophysical status of vegetation, including water stress caused by soil water deficit. Based on the nominal links between water stress condition, transpiration and canopy temperature in the vegetation, numerous studies have used a trapezoidal relationship between Land ...
Rakesh Chandra Joshi, Dongryeol Ryu, Gary J. Sheridan, Patrick N.J. Lane   +3 more
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Why Normalized Difference Vegetation Index (NDVI)?

2022
Plants play a very important role in ecological systems -- they transform CO2 into oxygen. It is therefore very important to be able to estimate the overall amount of live green vegetation in a given area. The most efficient way to provide such a global analysis is to use remote sensing, i.e., multi-spectral photos taken from satellites, drones, planes,
Zapata, Francisco, Smith, Eric, Kreinovich, Vladik, Phuong, Nguyen Hoang   +3 more
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The interpretation of spectral vegetation indexes

IEEE Transactions on Geoscience and Remote Sensing, 1995
Empirical studies report several plausible correlations between transforms of spectral reflectance, called vegetation indexes, and parameters descriptive of vegetation leaf area, biomass and physiological functioning. However, most indexes can be generalized to show a derivative of surface reflectance with respect to wavelength.
Ranga B. Myneni, Forrest G. Hall, Piers J. Sellers, Alexander L. Marshak   +3 more
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