T. Richard, D. Guilbert, A. Ihamouten, H. Gundel, C. Borderon, M. Latrach, Xavier Dérobert
{"title":"Structural health monitoring of civil engineering structures using GPR detection of patch antenna resonance frequency changes","authors":"T. Richard, D. Guilbert, A. Ihamouten, H. Gundel, C. Borderon, M. Latrach, Xavier Dérobert","doi":"10.3997/2214-4609.201902599","DOIUrl":"https://doi.org/10.3997/2214-4609.201902599","url":null,"abstract":"Summary Wireless and inexpensive sensors present a great attractiveness and are of growing interest in such fields as civil engineering. In this study, the feasibility of a wireless sensing system, which consists of a patch antenna sensor and an external wireless interrogator, has been investigated. The patch antenna is designed to operate at two fundamental radiation modes (TM010 & TM001) in the L Radar-frequency band according to the IEEE standard. The ground penetrating radar (GPR) interrogator consists of a printed Ultra-wide band Vivaldi antenna which is connected to a network analyzer. In order to evaluate its ability to monitor civil engineering structures, the performed patch antenna is placed behind various controlled slabs and its resonance frequency is varied artificially. The outside GPR interrogator permits to follow the frequency shift by measuring the reflected signal of the patch antenna. A series of preliminary experimental tests were carried out in order to demonstrate the principle.","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126926539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Gopher antenna: A new efficient design for ground penetrating radar","authors":"V. Voipio","doi":"10.3997/2214-4609.201902586","DOIUrl":"https://doi.org/10.3997/2214-4609.201902586","url":null,"abstract":"Summary In this article, we propose a new design we call the “Gopher antenna”: a patch antenna structure which does not require a resistive load and is therefore more efficient than the current ground-penetrating radar (GPR) antennas. When tested, it works well in a GPR application as low as approximately -25 dB of the application’s original transmit power. The Gopher antenna also meets the general requirements for the GPR antennas: a received wide spectrum and a good impulse response. Departing from the common designs (bow-tie dipoles and horn/Vivaldi structures), the Gopher antenna is a patch-antenna structure consisting of a quarter-wave feeder and a parasitic half-wave patch with no resistive load. The Gopher antenna has a directive radiation pattern, a good impulse response without distortion, a reasonable cross-polarization ratio, and a good radiated spectrum also when placed on the ground.","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134145697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Using GPR to Evaluate the Stratigraphic Condition of the Mosaic of the Dolphins in Delos Island, Greece, in order to Adopt the necessary Conservation measures","authors":"M. Manataki, C. Maris, A. Sarris, A. Vafidis","doi":"10.3997/2214-4609.201902591","DOIUrl":"https://doi.org/10.3997/2214-4609.201902591","url":null,"abstract":"Summary The mosaics of Delos island are a significant body of the ancient Greek art of the Hellenistic period that are inscribed to UNESCO’s World Heritage List. In this study, GPR systems with frequencies of 1600MHz, 500MHz and 250MHz are used to evaluate the stratigraphic condition of the mosaic at house of the Dolphins that decorates the peristyle impluvium. All the obtained data were processed in MATLAB and both Bscans and depth slices were used for the interpretation. The 1600MHz system performed the best and it was possible to identify the boundaries of the mosaic layers as well as problematic areas, such as bulges and high levels of moisture that may cause deterioration. The results obtained from the 500MHz and 250MHz are complimentary to the ones obtained from the high frequency system as the emitted signals can reach deeper levels. Structural characteristics of the cistern below the main mosaic floor were mapped in some detail including five stone arches. The overall performance of the GPR was satisfactory and the resulted information will be taken into account for the upcoming conservation plans.","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114082573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"3D Reconstruction of Tree Roots under Heterogeneous Soil Conditions using Ground Penetrating Radar","authors":"Abderrahmane Aboudourib, M. Serhir, D. Lesselier","doi":"10.3997/2214-4609.201902596","DOIUrl":"https://doi.org/10.3997/2214-4609.201902596","url":null,"abstract":"Coarse roots can cause damage to pipes, pavements and building foundations. Hence, reconstructing tree root system in its three dimensions is of paramount importance to understand and reduce interactions between trees and urban infrastructures. Ground Penetrating Radar (GPR) is a promising non-invasive technique for the study of tree roots. In this contribution, a 3D GPR simulation was carried out on two roots having elemental architectures in order to be reconstructed. The simulation was performed with GprMax software under heterogeneous soil conditions. Considering a heterogeneous soil not only provided a realistic soil model, but also enabled us to test the robustness of our post-processing techniques. We mainly used a Singular Value Decomposition (SVD) combined with the matched filter technique","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126182992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mathematic Physical Equivalency of 2D Pure Waves in Seismics and Electromagnetics","authors":"T. Qin, T. Bohlen","doi":"10.3997/2214-4609.201902580","DOIUrl":"https://doi.org/10.3997/2214-4609.201902580","url":null,"abstract":"Summary For a long time people tried to find the inner connection between the seismic waves and electromagnetic (EM) waves to explain their similarity. For example, the acoustic wave and Shear Horizontal (SH) wave possess the similar mathematic expression with the Transversal Electric (TE) and Transversal Magnetic (TM) wave, respectly. In this paper, we summarize those waves into an uniform wave equation based on a concept we termed the “wave operator”. The spartial matrix derived from the wave operator consists of four parts in three directions: the direction component, the volume component, the shear component and the rotation component. We then proved the equivalency of different pure waves in 2D case using this uniform expression. Therefore the forward solver developed for the longitudinal, shear and rotation wave can be converted to each other with a simple substitution. The two numerical tests verified our proposition.","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131038857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Salcedo, S. Garambois, P. Bouteiller, J. Virieux
{"title":"Anisotropie matrix-free tomography using discontinuous Galerkin of GPR data acquired between boreholes in Rustrel carbonates","authors":"M. Salcedo, S. Garambois, P. Bouteiller, J. Virieux","doi":"10.3997/2214-4609.201902594","DOIUrl":"https://doi.org/10.3997/2214-4609.201902594","url":null,"abstract":"Summary An increasing number of Ground-Penetrating Radar (GPR) studies takes benefit from illumination capabilities provided by dense acquisitions between boreholes. Traveltime tomography, migration and full waveform inversion provide high-resolution images to be interpreted. Tomography is often performed under an isotropic assumption, although anisotropy may exist at different scales. A new tomography approach is investigated based on an anisotropic Eikonal solver for the forward problem and an adjoint formulation for inverse problem. The misfit gradient is computed directly without expressing the sensitivity matrix, leading to explicit contribution of anisotropic parameters. The parametrization of elliptical anisotropy based on vertical and horizontal velocities is preferred to a parametrization based on Thomsen parameters for a realistic synthetic example, inspired from a real example of GPR transmission tomography between two boreholes in a carbonate environment where an old gallery exists. The vertical velocity is nicely recovered while the anisotropy contribution stays small. However, the real application provides similar results either through a layered isotropic model or through a smoother anisotropic model. Geological information is, therefore, needed for further specific interpretation.","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"22 23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134423206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Giannakis, F. Tosti, Livia Lantini, Daniel Egyir, A. Alani
{"title":"Signal Processing For Tree-Trunk Investigation Using Ground Penetrating Radar","authors":"I. Giannakis, F. Tosti, Livia Lantini, Daniel Egyir, A. Alani","doi":"10.3997/2214-4609.201902601","DOIUrl":"https://doi.org/10.3997/2214-4609.201902601","url":null,"abstract":"Summary Invasive fungi diseases are considered one the biggest threats for the ash and oak forests in United Kingdom. To that extend, Ground Penetrating Radar (GPR) can provide a powerful diagnostic tool for assessing the health status of tree trunks based on their internal dielectric distribution. GPR acquisitions in tree-trunks is a unique problem that can not be approached with traditional GPR processing approaches. Typical interpretation tools like hyperbola fitting and migration should be adjusted and fine-tuned in order to be applicable for irregular measurements in a closed curve. The purpose of this paper is to provide GPR practitioners with a set of interpretation tools that can be applied in the field using commercial GPR antennas. In that context, a novel processing framework is presented that is fine-tuned for the current problem. The suggested scheme is successfully tested using both numerical and real data indicating the capabilities of GPR as a diagnostic tool for early detection of tree diseases.","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127728258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Data Augmentation in feature-space with Generative Adversarial Networks, applied to GPR-based Buried Threat Detection","authors":"Jordan M. Malof, Daniel Reichman, L. Collins","doi":"10.3997/2214-4609.201902604","DOIUrl":"https://doi.org/10.3997/2214-4609.201902604","url":null,"abstract":"Summary In this work we consider the problem of developing algorithms for automatic buried threat detection (BTD) in ground penetrating radar (GPR) data. Many such algorithms are supervised, and perform best when they can be trained on large quantities of labeled threat and non-threat GPR data, respectively. Unfortunately, such data is costly to collect, and therefore relatively scarce. One approach to mitigate this problem is data augmentation, in which novel training data is created by applying transformations to existing data. Prior work has shown that augmentation can indeed improve the training of GPR-based BTD algorithms. In this work, we explore the use of Generative Adversarial Networks (GANs) for data augmentation. GANs can be trained to generate novel, but highly realistic, data after training on a real-world dataset. GANs have yielded impressive results on many types of data, but they are notoriously difficult to train. In this work, we propose an approach, entitled featureGAN, that mitigates some of the challenges training GANs. We show that augmentation using featureGAN yields improved detection performance, and yields better performance than some naive alternative augmentation strategies. We also propose a metric for quantifying the success of GAN training, called the q-metric, which was crucial to achieving good results.","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130641113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Gennarelli, G. Ludeno, C. Noviello, F. Soldovieri, I. Catapano
{"title":"Full 3D Ground Penetrating Radar Imaging of Vertical Structures","authors":"G. Gennarelli, G. Ludeno, C. Noviello, F. Soldovieri, I. Catapano","doi":"10.3997/2214-4609.201902597","DOIUrl":"https://doi.org/10.3997/2214-4609.201902597","url":null,"abstract":"Summary This work deals with the application of ground penetrating radar (GPR) for imaging the inner of vertical elements, which is of interest for the diagnostics of columns or pillars as well as tree trunks. The structure is probed along its surface by means of vertical GPR scans. The imaging is tackled as an electromagnetic inverse scattering problem by accounting for the 3D vectorial nature of the scattering phenomenon. A linearized inversion algorithm based on the Truncated Singular Value Decomposition (TSVD) is adopted to achieve stable and accurate results. The performance of the solution approach is assessed by means of a study regarding the resolution limits also devoted to investigate how the density of measurement data affects the image quality. Furthermore, experimental results are reported to highlight the feasibility of the approach in preliminary controlled laboratory conditions.","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"370 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133117071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quasi-Measurement Pitch Change: A New Framework for Machine Learning on GPR","authors":"R. Ogura, T. Miyata","doi":"10.3997/2214-4609.201902581","DOIUrl":"https://doi.org/10.3997/2214-4609.201902581","url":null,"abstract":"Summary Ground-penetrating radar (GPR) is a geophysical method for non-destructive inspection of underground infrastructure. The main impediment to machine-learning-based classification of GPR data is gathering enough labeled data. Previous work done to solve this problem generated pseudo-GPR data through the numerical simulations done with expensive GPU clusters. In this paper, we propose a simple yet effective framework for machine learning with GPR data without enormous computational cost. The key idea of our method is quasi-measurement pitch changes (QMPC) that can obtain several times the amount of pseudo-data from real measurements. QMPCs are based on a simple sub-sampling procedure from real data, and no interpolation is applied for the pseudo-data. Thus, special hardware like GPU clusters are not required and no artifacts are produced by such an interpolation. Moreover, using QMPCs for test data allows us to apply ensemble learning at the inference phase of machine learning. The experimental results for the classification problem of buried objects clearly show that our framework can drastically improve accuracy with additional labeled data and without significantly increasing computational cost.","PeriodicalId":162237,"journal":{"name":"10th International Workshop on Advanced Ground Penetrating Radar","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114856306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}