A linear inversion scheme for microwave imaging of buried objects is presented in which arbitrary antennas are accounted for through their plane-wave transmitting and receiving spectra. INTRODUCTION Ground penetrating radar (GPR) is an efficient tool for microwave imaging of buried objects. Within the concept of diffraction tomography, as proposed by Devaney [1], several linear inversion scheme...

BACKGROUND Spindle positioning during an asymmetric cell division is of fundamental importance to ensure correct size of daughter cells and segregation of determinants. In the C. elegans embryo, the first spindle is asymmetrically positioned, and this asymmetry is controlled redundantly by two heterotrimeric Galpha subunits, GOA-1 and GPA-16. The Galpha subunits act downstream of the PAR polari...

Thymus-expressed chemokine (TECK) has been reported to chemoattract dendritic cells, thymocytes, and activated macrophages. Here, we show that TECK is a specific agonist for a human orphan receptor called GPR-9-6. We have determined the cDNA sequence of human GPR-9-6 and cloned the corresponding murine cDNA. Human and murine GPR-9-6 expression is very high in the thymus and low in lymph nodes a...

In this paper, results of GPR experiments carried out in Nalaih, Mongolia and Yakutsk, Russia will be shown. In the measurements, target is ground water and permafrost. Especially in these regions, there are special kind of permafrost structure, which are important in the study of permafrost. In Nalaih, there is “pingo”, which is composed of several layers including permafrost in the subsurface...

A method for detecting buried mines in ground penetrating radar (GPR) data using a Hough transform approach is described. GPR is one of three sensors used in the Mine Hunter/Killer (MH/K) system for detecting buried mines. A buried mine modeled as a point scatterer in object space gives rise to a hyperbolic response in GPR measurement space. Our approach uses the Hough transform to recover the ...

One of the main problems with the interpretation of GPR data is the strong ground reflection, obscuring signals arriving from just underneath the surface. The strength of this reflection can be reduced by deconvolution. This technique is especially useful when GPR is used to detect buried landmines. Parametric and non parametric time variant estimators are used for clutter characterization. Wav...

This ongoing monitoring study provides forensic search teams with systematic geophysical data over simulated clandestine graves for comparison to active cases. Simulated "wrapped," "naked," and "control" burials were created. Multiple geophysical surveys were collected over 6 years, here showing data from 4 to 6 years after burial. Electrical resistivity (twin electrode and ERI), multifrequency...

This paper presents statistical signal processing approaches for clutter reduction in Stepped-Frequency Ground Penetrating Radar (SF-GPR) data. In particular, we suggest clutter/signal separation techniques based on principal and independent component analysis (PCA/ICA). The approaches are successfully evaluated and compared on real SF-GPR time-series. Field-test data are acquired using a monos...

In recent years, trees in European countries have been increasingly endangered by emerging infectious diseases (EIDs). the United Kingdom, this has observed to affect whole woodlands and forests, threatening existence of some types trees. Although quarantine measures taken limit spreading such diseases, not yet effectively controlled leading millions affected EIDs. Ground-penetrating radar (GPR...