Vol. 46 No. 1 (2014)

The non-uniqueness in the solution of gravity inversion poses a major problem in the interpretation of gravity data. To overcome this ambiguity, "a priori" information is introduced by minimizing a functional that describes the geometrical or physical properties of the solution. This paper presents a 2D gravity inversion technique incorporating axes of anomalous mass concentration as constraints. The inverse problem is formulated as a minimization of the moment of inertia of the causative body with respect to the axes of the mass concentration. The proposed method is particularly applicable…

Fermentation is a crucial step in the post-harvest processing of cocoa beans. This process comprises mixed culture microbial activities on the cocoa bean pulp, producing metabolites that act as important precursors for cocoa flavour development. Variations in the microbial population dynamics during the fermentation process may induce changes in the overall process. Thus, the introduction of a specific microbial starter culture may improve the quality of the fermentation. This article discusses the effects ofthe addition of Saccharomyces cerevisae var. Chevalieri starter culture on cocoa bean…

The computation time in adiabatic quantum computing (AQC) is determined by the time limit of the adiabatic evolution, which in turn depends on the evolution path. In this research we have used the variational method to find an optimized path. For the simplest case involving a single qubit and for the most general path involving one or more independent interpolating functions, the result is path independent. This result does not change when there is an extra Hamiltonian term. We have also applied these two scenarios in AQC to a Hadamard gate. Adding an extra Hamiltonian gives a non-trivial…

In this study, we propose to use Dolichoderus thoracicus to act as a double agent; not only as an agent to control cocoa plant pests, but also as an agent for distributing Trichoderma sp., a fungus that suppresses the development of the black pod disease caused by Phytophthora palmivora. In the experiments, D. thoracicus was more attracted to honey-soil media (M5) and coconut waste pulp-soil media (M6). However, 10% sucrose-potato-soil media (M3) was the best media for growing Trichoderma sp. Morphological study showed that spores attached to many parts of D. thoracicus. The efficiency of D.…

In this work, acid-base complex pair polymer electrolyte membranes on sulfonated polysulfone with 1H-benzotriazole were investigated. Polysulfone was sulfonated in 1,2-dichloroethane using the homogeneous method with trimethylsilyl chlorosulfonate as sulfonating agent. The monomer mole ratio between polysulfone and trimethysilyl chlorosulfonate was 1:1.5.The sulfonated polysulfone was added with 1H-benzotriazole at mole ratios of x = 0.5 and x =1. The proton transfer from 1H-benzotriazole to the sulfonated polysulfone was measured using FTIR. Thermo-gravimetry analysis showed that the samples…

A linear code over a finite field is called Hermitian self-dual if the code is self-dual under the Hermitian inner-product. The Hermitian self-dual code is called MDS or near-MDS if the code attains or almost attains the Singleton bound. In this paper we construct new Hermitian self-dual MDS or near-MDS codes over and of length up to 14.

Titanium oxide (TiO2) was impregnated on the surface of titanosilicate-1 (TiO2/TS-1) and used as catalyst for hydroxylation of phenol with hydrogen peroxide. Calcination was conducted at various temperatures (400, 500, 600 and 700°C)in order to observe the effect on the structure and physicochemical properties towards catalytic activity for producing hydroquinone. The structure and physicochemical properties of the TiO2/TS-1 catalyst were characterized by several techniques, such as X-ray diffraction (XRD), infrared spectroscopy, nitrogen adsorption, pyridine adsorption and hydrophilic…