—A C-band four-frequency resonant stacked-patch array antenna is developed for synthetic thinned aperture ra-diometer measurements of hurricane force wind speeds. This antenna is being integrated into an aircraft instrument referred to as the Hurricane Imaging Radiometer (HIRAD). Details of the antenna design are presented along with antenna performance… (More)
Lateral tree-scale variability in plantations should be taken into account when scaling up from point samples, but appropriate methods for sampling and calculation have not been defined. Our aim was to define and evaluate such methods. We evaluated several existing and new methods, using data for throughfall, root biomass and soil respiration in mature oil… (More)
The aim was to devise a practical soil sampling design for oil palm plantations that takes into account tree-scale variability, thus facilitating detection of trends in soil properties over time. We geometrically evaluated the ability of linear sampling transects to represent the distribution of typical management zones and radial patterns known to… (More)
A two-stage (nested) iteration strategy, in which the outer iteration is analogous to a block Gauss-Seidel method and the inner iteration to a Jacobi method for each of these blocks, often are used in the numerical solution of discretized approximations to the neutron transport equation. This paper is concerned with the effect, within a continuous space… (More)
An adaptive method based on the trapezoidal rule for the numerical solution of Fredholm integral equations of the second kind is developed. The choice of mesh points is made automatically so as to equidistribute both the chauge in the discrete solution and its gradient. Some numerical experiments with this method are presented.
Nitrogen (N) losses in agroecosystems are a major environmental and economic issue. This issue is particularly pronounced in oil palm cultivation because oil palm production area is expected to increase to 12 Mha by 2050. N fertilization in oil palm plantations is mainly provided by mineral fertilizers, palm oil mill by-products, and biological fixation… (More)
In order to better understand how global climate change will affect greenhouse gas dynamics in wetland systems, an accurate quantification of global greenhouse gas emissions from these areas is essential. Despite a large proportion of wetlands occurring in tropical areas, data on greenhouse gas fluxes from these areas is limited. This study aimed to… (More)