Papers by Keyword: Multi-Reflection

Abstract: The present paper is to analyses the key parameters of multi-reflection in GPR Survey. At first, it introduced the theory and methods for GPR result explanation. Then it proposed the necessity to work on multi-reflection analysis. For the complexity of multi-reflection, it emphatically worked on secondary reflection. According to the distinction of travel routes, the secondary reflection was divided into two cases. In the first case, the incident wave reflected twice at every interface and in the second case, the incident wave reflected for twice at every layer, meanwhile, the second reflected wave penetrated into the next layer as new incident wave. In these two cases, the amount of received waves was different and their corresponding transmitting parameters were deduced in the present paper. According to the deduction, in the situation of multiple reflections, the two-way travel time increases gradually; the energy decreases sharply and the profile curves are similar to each other.

Abstract: The absorption characteristics of micro-structural material, such as “black silicon”, aroused extensive attention. In order to understand the impact of the micro-structure, based on Monte Carlo method, the optical simulation is used for absorption characteristics of micro-structural material. In this paper, the body material used for simulation is a kind of glass, BK7, which has been widely used. And, there are a number of 400 structual cells in the model. The bottom square of each cell is fixed to 50×50 µm, and the height of cells is adjustable. For each height, the reflectance, transmittance and absorption of microstructural material can be caculated. Then the relationship between the height and reflectance, transmittance and absorption can be built up. In our simulation, a very complex relationship between the absorption and the the structure of the material is showed. Generally, the absorption increases while the height of microstructual cell increasing.