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Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns
Published on: August 30, 2013
[Crop geometry identification based on inversion of semiempirical BRDF models]
Wen-jiang Huang1, Jin-di Wang, Xi-han Mu
1National Engineering Research Center for Information Technology in Agriculture, Beijing 100097, China. huangwj@nercita.org.cn
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|March 1, 2008
Summary
This study shows that bidirectional canopy reflected spectrum can identify wheat varieties with erective and horizontal structures. A new index, SPEI, is more sensitive than others for distinguishing crop geometry.
Area of Science:
- Remote Sensing
- Vegetation Radiometry
- Quantitative Spectroscopy
Context:
- Crop geometry significantly influences canopy spectral reflectance.
- Semi-empirical bidirectional reflectance distribution function (BRDF) models are used to analyze spectral data.
- Understanding the relationship between BRDF model parameters and biophysical properties is crucial.
Purpose:
- To investigate the identification of erective and horizontal crop varieties using bidirectional canopy reflected spectra.
- To develop and validate a new index (SPEI) for crop geometry identification.
- To assess the sensitivity of SPEI compared to existing indices like SSI and NDFI.
Summary:
- Bidirectional canopy reflected spectra and semi-empirical BRDF models were employed to study crop geometry.
- A novel Structure-sensitive Parameter sensitive index (SPEI) was defined based on BRDF kernel weights.
- SPEI demonstrated higher sensitivity in distinguishing crop geometry structures, enabling the identification of erective and horizontal wheat varieties.
Impact:
- This research provides a feasible method for identifying horizontal and erective wheat varieties using spectral data.
- The findings contribute to improved crop structure characterization through remote sensing.
- SPEI offers a promising tool for remote sensing applications in agriculture and vegetation science.
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