Results 11 to 20 of about 4,461,069 (318)
Leaf area index (LAI) and gap fraction. A discussion
Baltic Forestry, 2023 Methodological aspects of estimating leaf area from gap fraction measurements are discussed. Instead of the common practice of linking in the Beer-Lambert law leaf area index and clumping factor together, the clumping factor and Ross-Nilson geometry ...
Andres Kuusk
semanticscholar +1 more source
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2022 The influence of tree distribution and slope on canopy gap fraction (GF) and bidirectional reflectance factor (BRF) is shown here to be non-negligible.
Jun Geng, Jing M Chen, Lili Tu
semanticscholar +1 more source
Estimating Effective Leaf Area Index of Winter Wheat Based on UAV Point Cloud Data
Drones, 2023 Leaf area index (LAI) is a widely used plant biophysical parameter required for modelling plant photosynthesis and crop yield estimation. UAV remote sensing plays an increasingly important role in providing the data source needed for LAI extraction. This
Jie Yang +7 more
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A field test of forest canopy structure measurements with the CanopyCapture smartphone application [PDF]
PeerJ, 2022 Background Several smartphone applications have been developed for the purpose of low-cost and convenient assessments of vegetation canopy structure and understorey illumination. Like standard hemispherical photography, most of these applications require
Christopher H. Lusk
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GAPS BETWEEN FRACTIONAL PARTS, AND ADDITIVE COMBINATORICS [PDF]
The Quarterly Journal of Mathematics, 2015 We give bounds on the number of distinct differences $N_a-a$ as $a$ varies over all elements of a given finite set $A$, and $N_a$ is a nearest neighbour to $a$.
Balog, Antal +2 more
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LiDAR Voxel-Size Optimization for Canopy Gap Estimation
Remote Sensing, 2022 Terrestrial laser scanning of forest structure is used increasingly in place of traditional technologies; however, deriving physical parameters from point clouds remains challenging because LiDAR returns do not have defined areas or volumes.
C. Wade Ross +5 more
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Direct Measurements of Fractional Quantum Hall Effect Gaps [PDF]
Physical Review Letters, 2007 We measure the chemical potential jump across the fractional gap in the low-temperature limit in the two-dimensional electron system of GaAs/AlGaAs single heterojunctions. In the fully spin-polarized regime, the gap for filling factor nu=1/3 increases LINEARLY with magnetic field and is coincident with that for nu=2/3, reflecting the electron-hole ...
Khrapai VS +7 more
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Remote Sensing, 2020 This paper develops an algorithm to estimate vegetation canopy gap fraction (GF), taking advantage of the full Terrestrial Laser Scanner (TLS) resolution. After calculating the TLS angular resolution, the algorithm identifies the missing laser hits (gaps)
John Gajardo +4 more
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Sensitivity of LiDAR Parameters to Aboveground Biomass in Winter Spelt
Drones, 2023 Information about the current biomass state of crops is important to evaluate whether the growth conditions are adequate in terms of water and nutrient supply to determine if there is need to react to diseases and to predict the expected yield.
Carsten Montzka +4 more
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ASSESSMENT OF LIGHT ENVIRONMENT FOR HERBACEOUS VEGETATION IN SEMI-NATURAL GRASSLAND USING TIME-SERIES UAV DATA [PDF]
ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2023 Grasslands are important ecosystems containing unique biodiversity. It has been reported that some herbaceous species inhabiting grassland reduced its number and became extremely rare.
N. Miura, Y. Niwa, S. Yamada
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