A diffusion Monte Carlo method for charge density on a conducting surface at non-constant potentials

We develop a last-passage Monte Carlo algorithm on a conducting surface at non-constant potentials. In the previous researches, last-passage Monte Carlo algorithms on conducting surfaces with a constant potential have been developed for charge density at a specific point or on a finite region and a hybrid BIE-WOS algorithm for charge density on a conducting surface at non-constant potentials. In the hybrid BIE-WOS algorithm, they used a deterministic method for the contribution from the lower non-constant potential surface. In this paper, we modify the hybrid BIE-WOS algorithm to a last-passage Monte Carlo algorithm on a conducting surface at non-constant potentials, where we can avoid the singularities on the non-constant potential surface very naturally. We demonstrate the last-passage Monte Carlo algorithm for charge densities on a circular disk and the four rectangle plates with a simple voltage distribution, and update the corner singularities on the unit square plate and cube.

Ohmic and Diamagnetic Currents Contribution on the Electromagnetic Penetration Depth of a Conducting Surface

Due to its conducting electron, metal is a good reflector for electromagnetic wave. An electromagnetic wave penetrating a metallic surface has a finite penetrating depth. There are two limit that are well studied in the physics textbooks. They are high frequency electromagnetic wave penetrating a metal with small conductivity and a static (low frequency) field penetrating a superconductor (metal with infinitely large conductivity). In this article we study the intermediate regime between these two limits. By setting the electric current density as the total sum of both Ohmic and Diamagnetic currents, we derive the penetration depth in the intermediate regime., we show the transition between these two limits.

Comparison of Two designs of Inverted F antenna in n78 band

This paper consists of comparison of design of two inverted F shape antennas in n78 band (3500 MHz). The antennas shown in this paper have rectangular ground plate. First design has a conducting surface over ground plate which has an inverted F shaped strip in the same plane. The other design of antenna which is considered here has vertical shorting strip placed on it, which again has a rectangular plate perpendicular to it. Considering different parameters like radiation pattern, gain, VSWR and reflection coefficient here we will see the best results of both the antennas in n78 band and talk about the design which can be used in most of our applications

Mineralogical and geochemical characteristics of graphite-bearing rocks at Chenjere Area, south-eastern Tanzania: Implications for the nature and quality of graphite mineralization

This study focused on the mineralogical and geochemical characteristics of graphite-bearing rocks at Chenjere area by conducting surface geological mapping, geochemical and petrographical analyses with the intention of characterizing the nature of graphite occurrence in these lithological units. This paper presents results of the flake size, grade and mineralization extension of graphite in the graphitic gneiss. Field observations, petrographic investigation and comparison with other studies indicate that graphite occurrence at the Chenjere area is of sedimentary origin which fall under syngenetic type. The petrographic study revealed that nature of metamorphism of rocks in the Chenjere area is of high grade (amphibolite facies). Both field observations and petrographic studies indicate that minerals in the rock associated with graphite include quartz, feldspar (mostly K-feldspar) and biotite. Further, the mineralized zones are concordant to the rest of the lithologies of the area and biotite gneiss is forming the hangingwall and footwall. The rocks’ foliation is generally NE striking and dipping SE with the dip amount ranging from 30 to 60 degrees. The graphite mineralization at the study area occurs as medium to coarse grained crystalline, flake type graphite with long axis of up to 1000 micrometres in size. Graphite flakes are disseminated and oriented in the host rock that represents a normal metamorphic fabric. Geochemical results indicate that graphite contents in the host graphitic gneiss range from 3.03 wt.% to 16.00 wt.%. Mineralogy and texture of the graphite at Chenjere area meet the standards required for industrial applications in various advanced technologies. Keywords: Graphite Mineralization, Flake Graphite, Chenjere Area

Surface Reversal Method Algorithm Development

The reversal method introduced by previous research focuses in finding reference datum of topography data of cylinder end surface but somehow ignores the existence of error. This problem leads to the purpose in introducing an understanding of how this method can be improvised. Thus, in this paper, a primitive approach was done by introducing the algorithm of the surface reversal method and simulating the reversal method on a selected surface to test how it works. This paper used MATLAB software for the majority of data processing. It started by preparing two simulated surfaces which were surface A and surface B (180o rotation). Then, it continued with the preparation of surface by converting the surface data into an image file type which made surface A and surface B aligned in the same direction before conducting surface correlation and finally finding the best match point between both surfaces. These basic steps play an important role to ensure the whole procedure for the next future studies is accurate. The peak result at position (540 x 409) from surface correlation was able to ease the next procedure by having a proper position before doing surface subtraction. The algorithm developed through MATLAB has successfully demonstrated the primary steps of surface reversal method.