The ability to effectively use remotely sensed data for environmental analysis is dependent on understanding the underlying procedures and associated variances attributed to the data processing and image analysis technique. Equally important is understanding the error associated with the reference data used to assess the accuracy of image products. This paper details measurement variance accumu...

The major physiological processes of vegetation including photosynthesis and evapotranspiration are determined by the vegetation biophysical parameters that describe the canopy structure. Leaf area index (LAI) is one of the principal biophysical parameters in climate, weather, and ecological studies, and has been routinely estimated from remote sensing measurements. LAI is defined as one half t...

Estimating the contribution of forests to carbon sequestration is commonly done by applying forest growth models. Such models inherently use field observations, such as leaf area index (LAI), whereas relevant information is also available from remotely sensed images. The purpose of this study is to improve the LAI estimated from the physiological principles predicting growth (3-PG) model by com...

© 2014 ETRI Journal, Volume 36, Number 6, December 2014 http://dx.doi.org/10.4218/etrij.14.0113.1335 The Lai-Massey scheme, proposed by Vaudenay, is a modified structure in the International Data Encryption Algorithm cipher. A family of block ciphers, named FOX, were built on the Lai-Massey scheme. Impossible differential cryptanalysis is a powerful technique used to recover the secret key of b...

The objective of this study was to investigate an innovative approach for the estimation of Leaf Area Index (LAI) from EO data. To this aim multiangular CHRIS/PROBA data, from SPARC 2003 and 2004, were used in the inversion of PROSPECT-SAILH models using a numerical optimization technique based on Marquardt-Levenberg algorithm. The optimal spectral sampling to estimate LAI was investigated usin...

LAI (leaf area index) estimation from direct measurement is tedious or impossible in tree canopies because of the high number of leaves and the large plant size. Methods based on inversion of gap fraction measurements have therefore been proposed, where gap fraction is measured from light sensors (e.g. ceptometer, Cohen et al. 1995, LAI-2000, Stenberg et al., 1994) or fisheye photographs (e.g. ...

At Asiacrypt’99, Vaudenay modified the structure in the IDEA cipher to a new scheme, which they called as the Lai-Massey scheme. It is proved that 3-round Lai-Massey scheme is sufficient for pseudorandomness and 4-round Lai-Massey scheme is sufficient for strong pseudorandomness. But the author didn’t point out whether three rounds and four rounds are necessary for the pseudorandomness and stro...

This paper aims to retrieve temporal high-resolution LAI derived by fusing MOD15 products (1 km resolution), field-measured LAI and ASTER reflectance (15-m resolution). Though the inversion of a physically based canopy reflectance model using high-resolution satellite data can produce high-resolution LAI products, the obstacle to producing temporal products is obvious due to the low temporal re...

Leaf area index (LAI) is a major indicator for crop growth monitoring and yield estimation. Data assimilation as an effective tool for crop LAI estimation fully considers the properties of actual observations and physical model simulations. In this work, we present a new data assimilation scheme, introducing a very fast simulated annealing (VFSA) optimization algorithm into the process of crop ...