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INFLUENCE OF SKY CONDITIONS ON ESTIMATION OF PHOTOSYNTHETIC PHOTON FLUX DENSITY FOR AGRICULTURAL ECOSYSTEM
PPFD PAR Solar radiation PAR fraction Quantum-to-energy ratio Diffuse ratio Clearness index Sky conditions
2018/5/16
Photosynthetic photon flux density (PPFD: μmol m−2 s−1) is indispensable for plant physiology processes in photosynthesis. However, PPFD is seldom measured, so that PPFD ...
APPLICATION OF HYPERION DATA TO AGRICULTURAL LAND CLASSIFICATION AND VEGETATION PROPERTIES ESTIMATION IN SWITZERLAND
Agriculture Land Cover Classification Remote Sensing Hyper Spectral Object Vegetation Contextual
2015/7/29
On August 18, 2002, the Hyperion hyperspectral imager onboard the EO-1 platform recorded data over an intensively used
agricultural area in north western Switzerland, the Limpach Valley. The sensor’s...
ESTIMATION OF LEAF AREA INDEX USING GROUND SPECTRAL MEASUREMENTS OVER AGRICULTURE CROPS: PREDICTION CAPABILITY ASSESSMENT OF OPTICAL INDICES
Hyperspectral Precision agriculture Modelling Algorithm development Spectral indices LAI
2015/7/29
Leaf area index (LAI) is a key canopy descriptor that is used to determine foliage cover, and predict photosynthesis and
evapotranspiration in order to assess crop yield. Its estimation from remote ...
Feasibility of using pyranometers for continuous estimation of ground cover fraction in table grape vineyards
PAR Vitis vinifera global solar radiation
2014/10/28
This paper evaluates the feasibility of using pyranometers for continuous estimation of ground cover fraction (GCF) at remote, unattended sites. Photographical techniques were used for measuring GCF (...
Stator resistance estimation using ANN in DTC IM drives
Induction machine direct torque control (DTC) artificial neural network stator resistance estimation
2010/3/17
Torque control of induction motors (IM) requires accurate estimation of the flux in the motor. But the flux estimate, when estimated from the stator circuit variables, is highly dependent on the stato...
Comparison of daubechies wavelets for hurst parameter estimation
Daubechies wavelets fractional gaussian noise hurst estimation vanishing moment
2010/3/17
Time scale dependence on the working nature of wavelet analysis makes it a valuable tool for Hurst parameter estimation. Similar to other wavelet-based signal processing applications, the selection of...
Effect of transformer on stochastic estimation of voltage sag due to faults in the power system: a PSCAD/EMTDC simulation
Faults voltage sag type of transformer PSCAD/EMTDC uniform fault distribution number of sags
2010/3/17
Voltage sags in the electric power system are mostly due to faults in the power system. Voltage sag is characterized by its magnitude (the retained voltage), phase-angle jump, unbalance in the sag in ...
Estimation of Nutrient Elution and Removal on Sediment Surface of Clayey Canal Based on Hydraulic Model Experiments
water quality denitrification creek chemical oxygen demand
2009/9/10
A clayey canal tends to be selected over a concrete-lined canal to achieve water quality conservation in a land improvement project. Therefore, it is important to analyze quantitatively the interactio...
Impacts of Climatic Change on World Agricultural Product Markets: Estimation of Macro Yield Functions
global warming world food model crop yields agricultural product markets
2009/9/9
Climatic change through global warming and drought is a major issue for agricultural production. Most researchers who discuss climate changes report the yield changes estimated by using crop process m...
Seasonal temperature-based models for reference evapotranspiration estimation under semi-arid condition of Malawi
Irrigation agricultural water management crop water requirement wind effect modeling
2010/9/10
The importance of evapotranspiration in agricultural water management has been widely reported without doubt. The FAO Penman Monteith (FPM) equation is the sole recommended estimation method of refere...
An Estimation of Leaf Area in Edible Canna(Canna edulis Ker.)
Canna edulis Ker Edible canna LAI Leaf area
2009/8/6
An Estimation of Leaf Area in Edible Canna(Canna edulis Ker.).
Estimation of Instantaneous Peak Flows in Seyhan River Basin Using Regional Regression Procedures
Instantaneous Flows Flood Climatic and Morphometric Characteristics Best Subset Analysis Multivariate Analyses Regional Regression Equations
2009/1/13
Multivariate procedures for estimating instantaneous flood flows for various return periods in Seyhan river basin are presented in the study. Procedures aim at developing regression equations uscable...
Comparison of Parameter Estimation Methods for the Three-Parameter Generalized Pareto Distribution
three-parameter generalized Pareto distribution moments probability-weighted moments maximum likelihood principle of maximum entropy least squares
2009/1/12
The generalized Pareto distribution, which is a special case of both exponential and Wakeby distribution, has good potential for the analysis of flood peaks because of its inherent properties. In this...
A method for estimation of enzymatic browning and its suppression in apple slices
apple slices reflectance browning oxalate sulphite
2008/11/26
A described method is based on diffuse light reflectance in the spectral region 400-720 nm for the examination of enzymatic browning of apple slices. In this method apples are sliced as directly dippe...
Attempt of water retention characteristcs estimation as pedotransfer function for organic soils
organic soils pedotransfer functions water retention
2008/11/26
This paper presents the results of statistical-physical modelling (pedotransfer function) relating soil water content at defined values of soil water potential to selected physical and chemical parame...