scholarly journals Acoustic Imaging Using the Built-In Sensors of a Smartphone

Symmetry ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1065
Author(s):  
Chenming Li ◽  
Junchao Wang ◽  
Xinyi Ding ◽  
Naiyin Zhang
Keyword(s):  
Microphone Array ◽  
Semiconductor Industry ◽  
Rapid Development ◽  
Target Object ◽  
Acoustic Imaging ◽  
Sound Waves ◽  
Reflected Waves ◽  
Acceleration Data ◽  
Specific Frequency ◽  
External Equipment

Thanks to the rapid development of the semiconductor industry, smartphones have become an indispensable part of our lives with their increasing computational power, 5G connection, multiple integrated sensors, etc. The boundary of the functionalities of a smartphone is beyond our imagination again and again as the new smartphone is introduced. In this work, we introduce an acoustic imaging algorithm by only using the built-in sensors of a smartphone without any external equipment. First, the speaker of the smartphone is used to emit sound waves with a specific frequency band. During the movement of the smartphone, the accelerometer collects acceleration data to reconstruct the trajectories of the movements, while the microphones receive the reflected waves. A microphone plus an accelerometer are able to partially replace the functionality of a microphone array and to become a symmetry-imitation system. After scanning, a series of algorithms are implemented to generate a heat map, which outlines the target object. Our algorithm demonstrates the feasibility of smartphone-based acoustic imaging with minimal equipment complexity and no additional cost, which is beneficial to the promotion and popularization of acoustic imaging technology in daily applications.

scholarly journals Combining asynchronous microphone array measurements for enhanced acoustic imaging and volumetric source mapping

2021 ◽  
Vol 182 ◽  
pp. 108247
Author(s):  
Lourenço Tércio Lima Pereira ◽  
Roberto Merino-Martínez ◽  
Daniele Ragni ◽  
David Gómez-Ariza ◽  
Mirjam Snellen
Keyword(s):  
Microphone Array ◽  
Acoustic Imaging ◽  
Array Measurements

Comparison of Sound Pressure Level of Conventional and Modified Mufflers by using CFD Analysis

2021 ◽  
Vol 8 (01) ◽  
pp. 63-67
Author(s):  
Zahoor Ullah ◽  
◽  
Hassan Ahmed ◽  
Kareem Akhtar ◽  
◽  
...  
Keyword(s):  
Sound Pressure Level ◽  
Sound Pressure ◽  
Combustion Engine ◽  
Pressure Level ◽  
Destructive Interference ◽  
Cfd Analysis ◽  
Sound Waves ◽  
Reflected Waves ◽  
Engine Cylinder ◽  
Real Challenge

The reduction of noise emitted from the exhaust of internal combustion engine is a real challenge for all automotive industries. Mufflers are designed to reflect sound waves produced by the engine in such a way to cancel the effect of each other by destructive interference between the incoming waves from engine cylinder and reflected waves from the muffler of the 2 stroke motorbike engine. Numerical simulation is carried out to study the sound pressure level (SPL) and flow variable like velocity and pressure of conventional and proposed modified reactive muffler.

Journey Toward Process Convergence in TSV Technology

2010 ◽  
Vol 2010 (DPC) ◽  
pp. 001282-001321
Author(s):  
Sesh Ramaswami ◽  
John Dukovic
Keyword(s):  
Process Integration ◽  
Semiconductor Industry ◽  
Rapid Development ◽  
Chemical Mechanical Planarization ◽  
Cost Effective ◽  
Superior Performance ◽  
Wafer Level ◽  
Unit Process ◽  
Integration Schemes ◽  
Process Convergence

Continuous demand for more advanced electronic devices with higher functionality and superior performance in smaller packages is driving the semiconductor industry to develop new and more advanced 3D wafer-level interconnect technologies involving TSVs (through-silicon vias). The TSVs are created either on full-thickness wafer from the wafer front-side ¡V as part of wafer-fab processing during Middle-Of-Line (¡§via middle¡¨) or Back-End-Of-Line (¡§via last BEOL¡¨) ¡V or from the wafer backside after wafer thinning (¡§via last backside¡¨). Independent of the specific approach, the main steps include via etching, lining with insulator, copper barrier/seed deposition, via fill, and chemical mechanical planarization (CMP). Over the past year, the industry has been converging toward some primary unit processes and integration schemes for creating the TSVs. A common cost-of-ownership framework has also begun to emerge. Active collaboration underway among equipment suppliers, materials providers and end users is bringing about rapid development and validation of cost-effective TSV technology in end products. This presentation will address unit-process and integration challenges of TSV fabrication in the context of 20x100ƒÝm and 5x50ƒÝm baseline process flows at Applied Materials. Highlights of wafer-backside process integration involving wafers bonded to silicon or glass carriers will also be discussed.

Accelerating Development of Materials for Industrial and High-Tech Applications with Data-Driven Analysis and Simulations

MRS Advances ◽  
2020 ◽  
Vol 5 (29-30) ◽  
pp. 1497-1511
Author(s):  
Sergey V. Barabash
Keyword(s):  
Semiconductor Industry ◽  
Rapid Development ◽  
Data Driven ◽  
Advanced Materials ◽  
High Tech ◽  
Phase Identification ◽  
Success Rates ◽  
Additional Material ◽  
High Throughput Experimentation ◽  
Reasonable Cost

ABSTRACTWe describe how the development of advanced materials via high-throughput experimentation at Intermolecular® is accelerated using guidance from modelling, machine learning (ML) and other data-driven approaches. Focusing on rapid development of materials for the semiconductor industry at a reasonable cost, we review the strengths and the limitations of data-driven methods. ML applied to the experimental data accelerates the development of record-breaking materials, but needs a supply of physically meaningful descriptors to succeed in a practical setting. Theoretical materials design greatly benefits from the external modelling ecosystems that have arisen over the last decade, enabling a rapid theoretical screening of materials, including additional material layers introduced to improve the performance of the material stack as a whole, “dopants” to stabilize a given phase of a polymorphic material, etc. We discuss the relative importance of different approaches, and note that the success rates for seemingly similar problems can be drastically different. We then discuss the methods that assist experimentation by providing better phase identification. Finally, we compare the strengths of different approaches, using as an example the problem of identifying regions of thermodynamic stability in multicomponent systems.

Broadband Random Phase Diffuser for Ultrasonic Imaging

1979 ◽  
Vol 1 (4) ◽  
pp. 325-332
Author(s):  
Gerard A. Alphonse ◽  
David Vilkomerso
Keyword(s):  
Solid Angle ◽  
Random Phase ◽  
Ultrasonic Imaging ◽  
Standing Waves ◽  
Acoustic Imaging ◽  
Point Sources ◽  
Phase Plate ◽  
Reflected Waves ◽  
Large Aperture ◽  
The Waves

In reflective imaging, waves must be scattered by the object over a broad solid angle so that some of the reflected waves impinge upon the collecting aperture. Surfaces such as biological specimens under study in acoustic imaging are considered smooth at the wavelengths used (e.g., 1 mm) and therefore act as specular reflectors. In order to obtain reflection over a broad spatial range, large aperture, sector or compound scanning are used. In certain types of systems, diffuse insonification is sometimes used by imaging a raster of random phase points onto the surface. However interference between the waves from these point sources produces random fringes or “speckle-like” patterns overlaying the image. In optics these fringes have been reduced by rotating the diffuser. A similar approach has been taken here. This paper describes a simple random phase plate having two levels, 0° and 180 phase that can, by rotation, change the relative phases of the diffuse insonification points so as to reduce the speckle-like effect in the image. The temporal bandwidth of the random phase plate is narrow because of standing waves in it. To reduce standing waves the diffuser is intimately coupled to a wedged transducer. This combination is used to obtain diffuse insonification with broad spatial and temporal bandwidth.

Investigating Rigidity of Military Vehicle Body Using Operating Deflection Shape (ODS) Analysis

2006 ◽  
Vol 49 (2) ◽  
pp. 16-24 ◽  
Author(s):  
Mark Bounds ◽  
George White
Keyword(s):  
Rigid Body ◽  
Dynamic Models ◽  
The Body ◽  
Vehicle Body ◽  
Rigid Body Dynamic ◽  
Military Vehicle ◽  
Acceleration Data ◽  
Specific Frequency ◽  
Body Dynamic ◽  
Insight Into

The Army has many rigid-body dynamic models of various vehicle platforms. The adequacy of these rigid-body models has been questioned. In an effort to gain insight into the significance of flexibility in the development of dynamic vehicle models, operating deflection shape (ODS) techniques were applied to acceleration data gathered from the body of a wheeled military vehicle. The data were analyzed in an effort to determine a specific frequency range over which the assumption of rigidity would be valid. For the particular platform examined in this study, the assumption of rigidity would apply up to approximately 14 Hz. Future efforts include using operational modal analysis (OMA) to further examine the problem.

Numerical simulations of the nonlinear kink modes in linearly stable supersonic slip surfaces

1991 ◽  
Vol 225 ◽  
pp. 101-120 ◽  
Author(s):  
Jeffrey A. Pedelty ◽  
Paul R. Woodward
Keyword(s):  
Numerical Simulations ◽  
Slip Surface ◽  
Nonlinear Resonance ◽  
Analytic Solutions ◽  
Nonlinear Behaviour ◽  
Sound Waves ◽  
Reflected Waves ◽  
Analytic Work ◽  
Slip Surfaces ◽  
Piecewise Parabolic

We have performed high-resolution numerical simulations of supersonic slip surfaces to confirm and illuminate earlier analytic nonlinear stability calculations of such structures. This analytic work was in turn inspired by earlier computer simulations reported in Woodward (1985) and Woodward et al. (1987). In particular Artola & Majda (1987) examined the response of a supersonic slip surface to an incident train of small-amplitude nonlinear sound waves. They found analytic solutions which indicate that nonlinear resonance occurs at three angles of incidence which depend upon the Mach number of the relative motion. The two-dimensional simulations described here numerically solve this problem for a Mach-4 flow using the piecewise-parabolic method (Colella & Woodward 1984; Woodward & Colella 1984). The simulations show that sound waves incident at a predicted resonance angle excite nonlinear behaviour in the slip surface. At these angles the amplitude of the reflected waves is much greater than the incident wave amplitude (i.e. a shock forms). The observed resonance is fairly broad, but the resonance narrows as the strength of the incident waves is reduced.The nature of the nonlinear kink modes observed in the simulations is similar to that discussed by Artola & Majda. Most of the modes move in either direction with speeds near the predicted value. Speeds of other than this value are observed, but the disagreement is not serious in view of the strongly nonlinear behaviour seen in the simulations but not treated in the analytic work. The stationary modes seen in the analytic results are perhaps observed as transient structures. They may eventually dominate the flow at late times (Woodward et al. 1987).The role of the kink modes in the stability of slab jets is discussed, and it is argued that the stationary modes are more disruptive than the propagating modes.

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