Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
In the detection of diseases on urban and rural roads and underground pipelines, we require to locate the position of disease or pipeline precisely and obtain relevant information as much as possible. The ground-penetrating radar system in this paper uses differential GPS positioning while recording, to obtain precise location of the disease. It uses high-precision camera systems to collect information...
Manual data acquisition with holographic subsurface radar is quite tedious as it requires monotonous scanning with precise positioning at the beginning of each scan line and requirement to move along straight lines to obtain a microwave hologram. A good result with manual scanning requires some practice, which still leaves such difficulties as maintaining constant press to evade image interlace and...
We report an advanced mathematical method featuring both antenna miniaturization and bandwidth enhancement for super wideband (SWB) antennas intended for advanced GPR applications. By implementing the supershape formula a wide range of practical antenna shapes can be described by just three design parameters, facilitating a lot the optimum antenna design. As a proof-of-concept, a PCB-based, balanced-fed...
Rebar detection can be cast as a the problem of localizing point-like scatterers sparsely enclosed within a prescribed investigation domain. Both TR-MUSIC and Compressed Sensing approaches can deal with it and are compared in this paper. The role of noise on data, data sparseness and mutual coupling are examined by numerical examples.
A new way is proposed for GPR studies of the rocks in confined spaces. Given is the description for experimental installations. The basic parameters are presented of angular scanning and of probing from different angles in limits one location. Standard ground-penetrating radar is equipped with a device for measuring the angle of inclination. It is located in a recess, in the shape of a half-cylinder,...
Through-wall sensing of hidden objects is a topic that is receiving a wide interest in several application contexts, especially in the field of security. The success of the object retrieval relies on accurate scattering models as well as on reliable inversion algorithms. In this paper, a contribution to the modeling of direct scattering for Through-Wall Imaging applications is given. The approach...
Interferometric methods can be used to create virtual sources at locations of physical receivers. Then the effect of changing surface conditions is minimized and these will not play a role in the antenna surface impedance changes. Replacing physical source locations by virtual sources at physical receiver locations is feasible using cross-correlation and multi-dimensional deconvolution techniques...
The Qinghai-Tibet Railway, the highest railroad in the world, stretches 1,956 kilometers from Xining to Lhasa in China. Of this ∼2000 km total length about one half of it (∼960 km) is on permafrost subgrades. Frozen earth disaster and other subgrade diseases lead to subgrade instability and affect the security of railway transportation. It is critical to develop a rapid and efficient technique for...
The paper discusses the diagnostic abilities of the 3D imaging GPR technique on a practical level, applied to data collected by frequency-domain equipment in reflection configuration and visualized using the method of horizontal slices. This method is particularly efficient in the detection of reinforcement and large infrastructural objects of linear shape. It is especially interesting that the method...
Pipe Penetrating Radar (PPR) is the underground, in-pipe application of GPR, a non-destructive testing method that can detect defects and cavities within and outside mainline diameter (>18 in / 450mm) non-ferrous (concrete, PVC, HDPE, vitrified clay, etc.) underground pipes [1, 2]. The method uses two or more high frequency GPR antennae carried by a robot into underground pipes. The radar data...
The first recognition of the Jupiter system, performed by the Voyager spacecraft, suggested the possibility of an ocean of liquid water beneath the ice shell two of Jupiter's moons, Ganymede and Europa. In addition, the Galileo mission detected in the icy shell the presence of impurities like magnesium and sodium sulfates, and sulfuric and hydrochloric acids. JUICE - JUpiter ICy moons Explorer will...
The icy satellites of Jupiter are known to host a water ocean beneath an ice shell. The ice penetrating Radar for Icy Moon Exploration (RIME) housed on board the JUpiter ICy moons Explorer (JUICE) mission is expected to probe the crust of Europa, Ganymede and Callisto up to a depth of 9 km. The main objectives of RIME are the detection of the relic Brittle-Ductile Transition in the ice shell of Ganymede...
Details of the temporal and spectral study on the transmission and propagation of EM wave in a 3D-volume model for tunnel boring machine (TBM) environment using near-field power (NFP) approach are reported herewith. Typical TBM's common underground deposits (sand, silt, clay, limestone, granite) with different degrees of wetness (varying from 0% to 20%) are investigated using full-wave electromagnetic...
This paper deals with the study of the GPR technique for timber structures evaluation. According to the electromagnetic (EM) theory, GPR wave's propagation is governed by the EM properties of a dielectric material as wood, which is affected by various parameters such as moisture, as well as heterogeneities.
In this paper the effect of local variability of soil moisture within the antenna footprint on GPR data is studied. A combination of GprMax3D with GPR full-wave model of Lambot and André (2013) is used for an errorless set of measurements. The GprMax3D simulations are used as real GPR measurements regarding several physical-based configurations. The Greens functions of the simulated data are extracted...
Our objective is the development of a prognosis system that predicts the soil-dependent GPR performance in landmine and improvised explosive device (IED) contaminated areas. One of the soil properties influencing sensing depth and image resolution of GPR is intrinsic attenuation. We investigated the frequency-dependent electromagnetic properties of a broad range of soil samples. In order to derive...
Airborne ground penetrating radar (GPR) is a promising technology to investigate wide areas or inaccessible regions. The effectiveness of an airborne GPR system not only depends on its hardware design, but also relies on the adopted imaging approaches. Some synthetic-aperture-radar (SAR) imaging algorithms have been successfully used to provide well-focused images with accurate target localization...
The implementation of the Pyramidal Mallat algorithm to GPR data, according to the analysis of its transient nature, is proposed. This is a decomposition method of the discrete wavelet transform which introduces a variable and scalable wavelet length, with compact support and limited band in the frequency domain. GPR data were analyzed in a time-frequency plane and are synthesized at different levels...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.