scholarly journals Improvement of Range Estimation with Microphone Array

2017 ◽  
Vol 17 (1) ◽  
pp. 113-125 ◽  
Author(s):  
Volodymyr Kudriashov
Keyword(s):  
Acoustic Noise ◽  
Microphone Array ◽  
Three Dimensional ◽  
Simultaneous Estimation ◽  
Destructive Testing ◽  
Sound Sources ◽  
Range Resolution ◽  
Incoming Signal ◽  
Emitter Localization ◽  
Non Destructive

Abstract This paper presentsanew approach for the three-dimensional (3-D) localization of sound sources. An acoustic camera uses an angular beamforming to measure the Direction of Arrival (Do A) of an incoming signal, to localize the emission source. The acoustic sensor used in this article is the Brüel & Kjaer acoustic camera transformed to operate inabistatic mode. The transformation consists inaplacing of one of the microphones of the acoustic camera outside of its microphone array. This allows simultaneous estimation of the Do Aand the Time Difference of Arrival (TDo A) of the incoming signal(s). Such sensors were not found. The paper proposes emitter localization in range - cross range - elevation coordinates by combining estimates of TDo Aand Do Aand presents the signal processing method for that purpose. The range resolution of 0.2mwas achieved in an experiment. Experimental results were obtained using different emission sources. Adescription of resolution cell limitations is presented. The obtained results show acoustic noise source localization without the pre-metering of the range of the imaging plane, i.e., withoutaneed to use the additional range meter which is notapart of the acoustic camera. The latter is important in tasks of non-destructive testing.

Acoustic and Photoacoustic Inspection of Through-Silicon Vias in the GHz-Frequency Band

2017 ◽  
Author(s):  
Sebastian Brand ◽  
Michael Kögel ◽  
Frank Altmann ◽  
Ingrid DeWolf ◽  
Ahmad Khaled ◽  
...  
Keyword(s):  
Quality Assessment ◽  
Frequency Band ◽  
Process Development ◽  
Three Dimensional ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Vertical Interconnection ◽  
Testing Techniques ◽  
Silicon Vias ◽  
Non Destructive

Abstract Through Silicon Via (TSV) is the most promising technology for vertical interconnection in novel three-dimensional chip architectures. Reliability and quality assessment necessary for process development and manufacturing require appropriate non-destructive testing techniques to detect cracks and delamination defects with sufficient penetration and imaging capabilities. The current paper presents the application of two acoustically based methods operating in the GHz-frequency band for the assessment of the integrity of TSV structures.

INSPECTION BY ULTRASONIC TOMOGRAPHY (UT) LEADING TREND IN WELDING JOINT MONITORING

2015 ◽  
Vol 77 (17) ◽  
Author(s):  
Noor Amizan Abd. Rahman ◽  
Ruzairi Abdul Rahim ◽  
Nor Muzakkir Nor Ayob ◽  
Jaysuman Pusppanathan ◽  
Fazlul Rahman Mohd Yunus ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Image Resolution ◽  
Ultrasonic Tomography ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Steel Pipes ◽  
Imaging Result ◽  
Welding Steel ◽  
Joint Monitoring ◽  
Non Destructive

Welding work is a connection process between the structure and the materials. This process is used in the construction, maintenance and repair especially mechanical engineering. This study discusses the type of welding used in the industry, mainly involving the pipeline welds. On-demand need to every work process when finishing weld requires quality tests to ensure compliance to the standards required. Monitoring through the display image has long been used in Non-Destructive Testing (NDT). Various methods of monitoring used in NDT focused on Ultrasonic Tomography (UT) as a method used in NDT and as an option for the future. Previous imaging result was in two-dimensional (2D) and then upgraded to a three-dimensional image (3D). Besides, there is potential of 3D imaging beyond the existing limits in terms of size, material thickness, especially for welding steel pipes. Achievement through research of existing pipe size so far outside diameter of 200 mm and a thickness of 5.8 mm should be limited in view of the obstacles to enhanced image resolution is less effective when compared to other tomography methods.

scholarly journals The Examination of Restrained Joints Created in the Process of Multi-Material FFF Additive Manufacturing Technology

Materials ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 903 ◽  
Author(s):  
Janusz Kluczyński ◽  
Lucjan Śnieżek ◽  
Alexander Kravcov ◽  
Krzysztof Grzelak ◽  
Pavel Svoboda ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Three Dimensional ◽  
Acrylonitrile Butadiene Styrene ◽  
Tensile Tests ◽  
Lower Amount ◽  
Internal Quality ◽  
Experimental Production ◽  
Destructive Testing ◽  
Non Destructive

The paper is focused on the examination of the internal quality of joints created in a multi-material additive manufacturing process. The main part of the work focuses on experimental production and non-destructive testing of restrained joints of modified PLA (polylactic acid) and ABS (Acrylonitrile butadiene styrene) three-dimensional (3D)-printed on RepRap 3D device that works on the “open source” principle. The article presents the outcomes of a non-destructive materials test in the form of the data from the Laser Amplified Ultrasonography, microscopic observations of the joints area and tensile tests of the specially designed samples. The samples with designed joints were additively manufactured of two materials: Specially blended PLA (Market name—PLA Tough) and conventionally made ABS. The tests are mainly focused on the determination of the quality of material connection in the joints area. Based on the results obtained, the samples made of two materials were compared in the end to establish which produced material joint is stronger and have a lower amount of defects.

scholarly journals A Cost-Effective System for Aerial 3D Thermography of Buildings

2020 ◽  
Vol 6 (8) ◽  
pp. 76
Author(s):  
Claudia Daffara ◽  
Riccardo Muradore ◽  
Nicola Piccinelli ◽  
Nicola Gaburro ◽  
Tullio de Rubeis ◽  
...  
Keyword(s):  
3D Imaging ◽  
Three Dimensional ◽  
Cost Effective ◽  
Complex Structures ◽  
Non Destructive Testing ◽  
Ir Thermography ◽  
Destructive Testing ◽  
Effective System ◽  
Reconstruction Software ◽  
Non Destructive

Three-dimensional (3D) imaging and infrared (IR) thermography are powerful tools in many areas in engineering and sciences. Their joint use is of great interest in the buildings sector, allowing inspection and non-destructive testing of elements as well as an evaluation of the energy efficiency. When dealing with large and complex structures, as buildings (particularly historical) generally are, 3D thermography inspection is enhanced by Unmanned Aerial Vehicles (UAV—also known as drones). The aim of this paper is to propose a simple and cost-effective system for aerial 3D thermography of buildings. Special attention is thus payed to instrument and reconstruction software choice. After a very brief introduction to IR thermography for buildings and 3D thermography, the system is described. Some experimental results are given to validate the proposal.

Research Based on Optical Non-Destructive Testing of Pigment Identification

2016 ◽  
Vol 16 (4) ◽  
pp. 3583-3586 ◽  
Author(s):  
Jigang Wang ◽  
Shengcai Hao ◽  
Wenhua Zhou ◽  
Xiaokun Qi ◽  
Jilong Shi
Keyword(s):  
Three Dimensional ◽  
Potential Method ◽  
Identification System ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
X Ray ◽  
Ultramarine Blue ◽  
Bright Yellow ◽  
Cultural Relic ◽  
Non Destructive

Optical Non-Destructive Testing (ONDT) can be applied as penetrating elemental and structure analysis technology in the pigments identification field. Three-dimensional video microscopy, Raman microscopy and energy dispersive X-ray fluorescence spectroscopy are employed to measure the materials based on a Qing Dynasty meticulous painting. The results revealed that the dark yellow area within the decorative patterns was presented due to the interaction of Emerald green and hematite, and the bright yellow edge area was delineated by Cu–Zn–Pb composition. The interesting thing is that an artificial synthetic ultramarine blue was checked in the painting. According to the first synthesized time of ultramarine blue and Paris green, the time limit of the painting completion can be identified. The principle of Pigment subtractive colorant and nitikaset method were employed to interpreting the results. Optical testing combined with the area of cultural relic identification can be a potential method to build an expert identification system successfully. This work also help lay the optical method groundwork for further cultural relic identification, sterilization, and preservation.

scholarly journals Localisation of Vertical Auditory Phantom Image with Band-limited Reductions of Vertical Interchannel Crosstalk

2020 ◽  
Vol 10 (4) ◽  
pp. 1490
Author(s):  
Rory Wallis ◽  
Hyunkook Lee
Keyword(s):  
Microphone Array ◽  
Practical Implication ◽  
Three Dimensional ◽  
Source Image ◽  
Octave Band ◽  
Sound Sources ◽  
Phantom Image ◽  
3D Sound ◽  
Subjective Experiment ◽  
Band Limited

Direct sound that is captured by the upper layer of a three-dimensional (3D) microphone array is typically regarded as vertical interchannel crosstalk (VIC), since it tends to produce an undesired effect of the sound source image being elevated from the ear-level loudspeaker layer position (0°) in reproduction. The present study examined the effectiveness of band-limited VIC attenuation methods on preventing the vertical image shift problem. In a subjective experiment, five natural sound sources were presented as vertically-oriented phantom images while using two stereophonic loudspeaker pairs elevated at 0° and 30° in front of the listener. The upper layer signal (i.e., VIC) was attenuated in various octave-band-dependent conditions that were based on vertical localisation thresholds obtained from previous studies. The results showed that it was possible to achieve the goal of panning the phantom image at the same height as the image produced by the main loudspeaker layer by attenuating only a single octave band with the centre frequency of 4 kHz or 8 kHz or multiple bands at 1 kHz and above. This has a useful practical implication in 3D sound recording and mixing where a vertically oriented phantom image is rendered.

X-Ray Microtomography of Microcellular Polymers

2000 ◽  
Author(s):  
Ryszard Pyrz
Keyword(s):  
Three Dimensional ◽  
Stress And Strain ◽  
Geometrical Parameters ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
X Ray ◽  
Testing Method ◽  
Measuring Techniques ◽  
Measured Stress ◽  
Non Destructive

Abstract Among modern measuring techniques, which are designed to reconstruct and to measure three-dimensional aspects of microstructure on mesoscopic scale lengths, the X-ray microtomography seems to be very well suited to yield this information. Generally, X-ray microtomography is the X-ray based non-destructive testing method that was first developed for medical purposes and only recently applied to materials characterization. Monitoring materials’ microstructure using X-ray microtomography allows reconstructing a three-dimensional image of the specimen from non-destructive, serial sections and processing it in order to visualize and measure three-dimensional features. Thus valuable information can be deduced from the correlation of measured stress and strain values with a number of internal geometrical parameters which cannot be measured at the specimen surface.

scholarly journals OPTO-TECHNICAL MONITORING – A STANDARDIZED METHODOLOGY TO ASSESS THE TREATMENT OF HISTORICAL STONE SURFACES

2018 ◽  
Vol XLII-2 ◽  
pp. 945-952
Author(s):  
M. Rahrig ◽  
R. Drewello ◽  
A. Lazzeri
Keyword(s):  
Near Field ◽  
Three Dimensional ◽  
Non Destructive Testing ◽  
New Materials ◽  
Testing Methods ◽  
Destructive Testing ◽  
Monitoring Method ◽  
Horizon 2020 ◽  
Research And Innovation ◽  
Non Destructive

Monitoring is an essential requirement for the planning, assessment and evaluation of conservation measures. It should be based on a standardized and reproducible observation of the historical surface. For many areas and materials suitable methods for long-term monitoring already exist. But hardly any non-destructive testing methods have been used to test new materials for conservation of damaged stone surfaces. The Nano-Cathedral project, funded by the European Union's Horizon 2020 research and innovation program, is developing new materials and technologies for preserving damaged stone surfaces of built heritage. The prototypes developed are adjusted to the needs and problems of a total of six major cultural monuments in Europe. In addition to the testing of the materials under controlled laboratory conditions, the products have been applied to trial areas on the original stone surfaces. For a location-independent standardized assessment of surface changes of the entire trial areas a monitoring method based on opto-technical, non-contact and non-destructive testing methods has been developed. This method involves a three-dimensional measurement of the surface topography using Structured-Light-Scanning and the analysis of the surfaces in different light ranges using high resolution VIS photography, as well as UV-A-fluorescence photography and reflected near-field IR photography.<br> The paper will show the workflow of this methodology, including a detailed description of the equipment used data processing and the advantages for monitoring highly valuable stone surfaces. Alongside the theoretical discussion, the results of two measuring campaigns on trial areas of the Nano-Cathedral project will be shown.

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