On the analysis of buried objects by processing 3-D acoustic images

2005 ◽  
Author(s):  
M. Palmese ◽  
A. Caiti ◽  
A. Trucco
Keyword(s):  
Buried Objects ◽  
Acoustic Images

Detection and characterisation of buried objects using infrared thermography enhanced by microwave heating

2002 ◽  
Author(s):  
Arnaud Jacotin ◽  
Elodie Bachelier ◽  
Francois Liousse ◽  
Pierre Millan
Keyword(s):  
Microwave Heating ◽  
Infrared Thermography ◽  
Buried Objects

Microwave enhancement of thermal detection of buried objects

2012 ◽  
Author(s):  
W. Swiderski ◽  
P. Hłosta ◽  
L. Szugajew ◽  
J. Usowicz
Keyword(s):  
Buried Objects ◽  
Thermal Detection

scholarly journals Use of Ultrasound Microscopy for Ex Vivo Analysis of Acoustic Impedance in Mouse Liver with Steatohepatitis

Acoustics ◽  
2020 ◽  
Vol 3 (1) ◽  
pp. 3-10
Author(s):  
Hideki Kumagai ◽  
Kazuto Kobayashi ◽  
Sachiko Yoshida ◽  
Koji Yokoyama ◽  
Norio Hirota ◽  
...  
Keyword(s):  
Acoustic Impedance ◽  
Ex Vivo ◽  
Acoustic Microscopy ◽  
Control Group ◽  
Scanning Acoustic Microscopy ◽  
Central Frequency ◽  
Deficient Diet ◽  
Acoustic Images ◽  
Ultrasound Microscopy

Scanning acoustic microscopy reveals information on histology and acoustic impedance through tissues. The objective of the present study was to investigate whether acoustic impedance values in the liver over time reflect the progression of steatohepatitis through different grades and stages, and whether this approach can visualize histologic features of the disease. Mice were divided into two groups: a control group and a steatohepatitis group prepared by keeping the mice on a methionine and choline-deficient diet for 56 weeks. The hepatic lobe was excised for measurement of impedance and observation of microscopic structure using a commercially available scanning acoustic microscopy system with a central frequency of 320 MHz. Scanning acoustic microscopy revealed that acoustic impedance through liver tissue with steatohepatitis temporarily decreased with the degree of fat deposition and then increased in parallel with the progression of inflammation and fibrosis. However, the acoustic images obtained did not allow discrimination of detailed microstructures from those seen using light microscopy. In conclusion, estimation of acoustic impedance appears to have potential clinical applications, such as for monitoring or follow-up studies.

scholarly journals Bearing and Range Estimation Algorithm for Buried Object in Underwater Acoustics

2009 ◽  
Vol 2009 ◽  
pp. 1-4
Author(s):  
Dong Han ◽  
Caroline Fossati ◽  
Salah Bourennane ◽  
Zineb Saidi
Keyword(s):  
Underwater Acoustics ◽  
Classical Model ◽  
Acoustic Scattering ◽  
Estimation Algorithm ◽  
Signal Classification ◽  
Music Algorithm ◽  
Range Estimation ◽  
Multiple Signal Classification ◽  
Buried Objects ◽  
Buried Object

A new algorithm which associates (Multiple Signal Classification) MUSIC with acoustic scattering model for bearing and range estimation is proposed. This algorithm takes into account the reflection and the refraction of wave in the interface of water-sediment in underwater acoustics. A new directional vector, which contains the Direction-Of-Arrival (DOA) of objects and objects-sensors distances, is used in MUSIC algorithm instead of classical model. The influence of the depth of buried objects is discussed. Finally, the numerical results are given in the case of buried cylindrical shells.

On: “3-D localization of buried objects by nearfield electromagnetic holography” (Y. Guo, H. W. Ko, and D. M. White, GEOPHYSICS, 63, 3, 880–889).

Geophysics ◽  
1999 ◽  
Vol 64 (4) ◽  
pp. 1335-1335
Author(s):  
Michael Zhdanov
Keyword(s):  
Electromagnetic Field ◽  
Low Frequency ◽  
Basic Principles ◽  
Buried Objects

The authors present a method of localizing underground objects with low‐frequency electromagnetic field based on ideas of electromagnetic holography. Though I do strongly support this method and practical results presented in the paper, I should note that the authors neglected in their paper to reference the previous publications on this subject, where the basic principles, ideas, methods, and term “electromagnetic holography” have been already introduced and developed as applied to low‐frequency electromagnetic field underground imaging.

scholarly journals Tactile Perception for Teleoperated Robotic Exploration within Granular Media

2021 ◽  
Vol 10 (4) ◽  
pp. 1-27
Author(s):  
Shengxin Jia ◽  
Veronica J. Santos
Keyword(s):  
Granular Media ◽  
Fluid Pressure ◽  
Tactile Sensor ◽  
Tactile Perception ◽  
Test Accuracy ◽  
Contact State ◽  
Buried Objects ◽  
Media Type ◽  
Additional Information ◽  
Internal Fluid

The sense of touch is essential for locating buried objects when vision-based approaches are limited. We present an approach for tactile perception when sensorized robot fingertips are used to directly interact with granular media particles in teleoperated systems. We evaluate the effects of linear and nonlinear classifier model architectures and three tactile sensor modalities (vibration, internal fluid pressure, fingerpad deformation) on the accuracy of estimates of fingertip contact state. We propose an architecture called the Sparse-Fusion Recurrent Neural Network (SF-RNN) in which sparse features are autonomously extracted prior to fusing multimodal tactile data in a fully connected RNN input layer. The multimodal SF-RNN model achieved 98.7% test accuracy and was robust to modest variations in granular media type and particle size, fingertip orientation, fingertip speed, and object location. Fingerpad deformation was the most informative modality for haptic exploration within granular media while vibration and internal fluid pressure provided additional information with appropriate signal processing. We introduce a real-time visualization of tactile percepts for remote exploration by constructing a belief map that combines probabilistic contact state estimates and fingertip location. The belief map visualizes the probability of an object being buried in the search region and could be used for planning.

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