A total of 21 gauges across the mountainous leeward portion of the island of Oʻahu, Hawaiʻi, were used to compare rainfall interpolation methods and assess rainfall spatial variability over a 34-month monitoring period from 2005 to 2008. Traditional and geo-statistical interpolation methods, including Thiessen polygon, inverse distance weighting (IDW),… (More)
Single capacitance sensors are sensitive to soil property variability. The objectives of this study were to: (i) establish site-specific laboratory calibration equations of three single capacitance sensors (EC-20, EC-10, and ML2x) for tropical soils, and (ii) evaluate the accuracy and precision of these sensors. Intact soil cores and bulk samples, collected… (More)
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Studies show that the performance of soil water content monitoring (SWCM) sensors is affected by soil physical and chemical properties. However, the effect of organic matter on SWCM sensor responses remains less understood. Therefore, the objectives of this study are to (i) assess the effect of organic matter on the accuracy and precision of SWCM sensors… (More)
The objective of this study was to use satellite imagery to monitor the water budget of Al Ain region in the United Arab Emirates (UAE). Inflows and outflows were estimated and the trend of water storage variation in the study area was examined from 2005 to 2014. Evapotranspiration was estimated using the simplified Penman-Monteith equation. Landsat images… (More)
In this paper we deal with the solvability of the infinite system of differential equations x (t) = ∆(λ)x(t) + b with x(0) = a, where ∆(λ) is the triangle defined by the infinite matrix whose the nonzero entries are [∆(λ)] nn = λ n and [∆(λ)] n,n−1 = λ n−1 for all n ∈ N, for a given sequence λ and a, b are two given infinite column matrices. We use a new… (More)
This paper presents a new algorithm for solving zero-dimensional parametric systems of polynomial homogeneous equations. This algorithm is based on the computation of what we call parametric U-resultants. The parameters space, i.e., the set of values of the parameters is decomposed into a finite number of con-structible sets. The solutions of the input… (More)
Spatially variable soil properties influence the performance of soil water content monitoring sensors. The objectives of this research were to: (i) study the spatial variability of bulk density (ρ(b)), total porosity (θ(t)), clay content (CC), electrical conductivity (EC), and pH in the upper Mākaha Valley watershed soils; (ii) explore the effect of… (More)