Modeling and simulation results of a system analysis of Ground Penetrating Radars (GPR) using Finite Difference Time Domain (FDTD) techniques are presented. Performance issues with GPRs need to be isolated in order to optimize of the radar’s ability to detect and identify buried objects. Using a system engineering approach, FDTD models were used to characterize the variables associated with the...

In this paper, a signal processing technique is developed to reduce clutter due to ground bounce in ground penetrating radar (GPR) measurements. This technique is especially useful when a GPR is used to detect subsurface antipersonnel mines. The GPR clutter is modeled using a simple parametric model. Buried mine and clutter contributions are separated through a pair of coupled iterative procedu...

Ground penetrating radar (GPR) is a nondestructive sensor technology for detecting underground objects. GPR requires large-aperture antennas to survey a remote location precisely because of the expansion of microwaves. We propose a laser-driven GPR (LGPR) that uses microwave radiation from a laser plasma to achieve remote sensing. LGPR is expected to provide good spatial resolution with a small...

Chemokines are likely to play an important role in regulating the trafficking of developing T cells within the thymus. By using anti-CD3varepsilon treatment of recombinase-activating gene 2 (Rag2-/-) mice to mimic pre-TCR signaling and drive thymocyte development to the double positive stage, we have identified murine GPR-9-6 as a chemokine receptor whose expression is strongly induced followin...

Traditional GPR Surveys. High-speed GPR surveys have been performed for many years to map the condition of aging bridge deck structures. Most often, one or more 1.0 GHz horn antennas are driven along unique survey paths spaced anywhere from 3 to 4ft apart—and 2 to 3 GPR scans are collected along every linear foot of the deck surface that is being sampled. Surface dielectric properties, signal a...

Gellenbeck, S. Mercy (Catholic University, Washington, D. C.). Aerobic respiratory metabolism of Staphylococcus aureus from an infected animal. J. Bacteriol. 83:450-455. 1962.-The separation of Staphylococcus aureus from the tissue fluids of an infected guinea pig has allowed a comparison of cells (GPR) separated in this manner with the same strain (PR847) grown on an artificial medium. In gene...

While there has been much interest in developing ground-penetrating radar (GPR) technology for rover-based planetary exploration, relatively little work has been done on the data collection process. Starting from the manual method, we fully automate GPR data collection using only sensors typically found on a rover. Further, we produce two novel data products: (1) a three-dimensional, photoreali...

It is well known in B-scan ground penetrating radar (GPR) imagery that the underground scatterers generally exhibit defocused, hyperbolic characteristics. This is mainly due to the data collection scheme and the finite beam width of the main lobe of the GPR antenna. To invert this undesirable effect and obtain focused images, various migration or focusing algorithms have been developed. In this...

In this paper we propose a novel Bayesian kernel based solution for regression in complex fields. We develop the formulation of the Gaussian process for regression (GPR) to deal with complex-valued outputs. Previous solutions for kernels methods usually assume a complexification approach, where the real-valued kernel is replaced by a complexvalued one. However, based on the results in complex-v...

The selection of a near-field or far-field ground-penetrating radar (GPR) model is an important question for an accurate but computationally effective characterization of medium electrical properties using full-wave inverse modeling. In this study, we determined an antenna height threshold for the near-field and farfield full-wave GPR models by analyzing the variation of the spatial derivatives...