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This paper examines the velocity profile of fuel issuing from a high-pressure single-orifice diesel injector. Velocities of liquid structures were determined from time-resolved ultrafast shadow images, formed by an amplified two-pulse laser…

Fluid Dynamics · Physics 2013-01-29 David Sedarsky , Saïd Idlahcen , Jean-Bernard Blaisot , Claude Rozé

Aeroacoustic emissions from intense evaporation are widely measured yet often treated as noisy byproducts and used mainly in empirical monitoring. Here, we show that airborne sound encodes physics-governed sub-millisecond fingerprints of…

We describe a novel method of single-shot trap frequency measurement for a confined Bose-Einstein Condensate, which uses an atom laser to repeatedly sample the mean velocity of trap oscillations as a function of time. The method is able to…

Quantum Gases · Physics 2022-04-12 B. M. Henson , K. F. Thomas , Z. Mehdi , T. G. Burnett , J. A. Ross , S. S. Hodgman , A. G. Truscott

Within the missile guidance and control system the autopilot must overcome an array of variables and uncertainties to maintain tracking trajectory. A large uncertainty explored in this paper is the difference between the assumed flight…

Systems and Control · Electrical Eng. & Systems 2024-11-12 Eerik Cockin , Xinhua Wang

We present Acoustic Inertial Measurement (AIM), a one-of-a-kind technique for indoor drone localization and tracking. Indoor drone localization and tracking are arguably a crucial, yet unsolved challenge: in GPS-denied environments,…

Robotics · Computer Science 2025-04-02 Yimiao Sun , Weiguo Wang , Luca Mottola , Zhang Jia , Ruijin Wang , Yuan He

A survey of acoustic devices for focusing airborne sound is presented. We introduce a new approach to design high quality acoustic lenses based on arrays of cylindrical rigid scatterers in air. A population based stochastic search algorithm…

Materials Science · Physics 2007-05-23 Andreas Hakansson , Jose Sanchiz-Dehesa , Lorenzo Sanchis

Sound waves cause small vibrations in nearby objects. A few techniques exist in the literature that can extract sound from video. In this paper we study local vibration patterns at different image locations. We show that different locations…

Computer Vision and Pattern Recognition · Computer Science 2019-07-16 Mohammad Amin Shabani , Laleh Samadfam , Mohammad Amin Sadeghi

We develop a system for measurements of power spectra of transmitted light intensity fluctuations, in which the extraneous noise, including shot noise, is reduced. In essence, we just apply light, measure the power of the transmitted light…

Atomic Physics · Physics 2023-07-19 Takahisa Mitsui , Kenichiro Aoki

Particulate materials include powders, emulsions, composites, and many others. This is why measuring these has become important for both industry and scientific applications. For industrial applications, the greatest need is to measure…

Statistical Mechanics · Physics 2024-07-10 Paulo S. Piva , Kevish K. Napal , Art L. Gower

A microphone array can provide a mobile robot with the capability of localizing, tracking and separating distant sound sources in 2D, i.e., estimating their relative elevation and azimuth. To combine acoustic data with visual information in…

Audio and Speech Processing · Electrical Eng. & Systems 2020-07-23 Simon Michaud , Samuel Faucher , François Grondin , Jean-Samuel Lauzon , Mathieu Labbé , Dominic Létourneau , François Ferland , François Michaud

Previous one-stage action detection approaches have modelled temporal dependencies using only the visual modality. In this paper, we explore different strategies to incorporate the audio modality, using multi-scale cross-attention to fuse…

Computer Vision and Pattern Recognition · Computer Science 2023-11-29 Hanyuan Wang , Majid Mirmehdi , Dima Damen , Toby Perrett

Unmanned air vehicles often produce significant noise from their propulsion systems. Using this broadband signal as "acoustic illumination" for an auxiliary sensing system could make vehicles more robust at a minimal cost. We present an…

Robotics · Computer Science 2023-04-18 Alisha Sharma , Jason Geder , Joseph Lingevitch , Theodore Martin , Daniel Lofaro , Donald Sofge

Noise pollution investigation takes advantage of two common methods of diagnosis: measurement using a Sound Level Meter and acoustical imaging. The former enables a detailed analysis of the surrounding noise spectrum whereas the latter is…

Instrumentation and Detectors · Physics 2016-03-28 Charles Vanwynsberghe , Régis Marchiano , François Ollivier , Pascal Challande , Hélène Moingeon , Jacques Marchal

We use published data on the power and production efficiency of jets in blazars with double radio lobes in order to compare results obtained using different methods. In order to eliminate selection effects, we use cross-matched sub-samples…

High Energy Astrophysical Phenomena · Physics 2016-12-28 Patryk Pjanka , Andrzej A. Zdziarski , Marek Sikora

In this paper, trajectory prediction and control design for a desired hit point of a projectile is studied. Projectiles are subject to environment noise such as wind effect and measurement noise. In addition, mathematical models of…

Systems and Control · Computer Science 2017-10-03 Cenk Demir , Abhyudai Singh

This paper introduces SmartBelt, a wearable microphone array on a belt that performs sound source localization and returns the direction of arrival with respect to the user waist. One of the haptic motors on the belt then vibrates in the…

Robotics · Computer Science 2022-03-01 Simon Michaud , Benjamin Moffett , Ana Tapia Rousiouk , Victoria Duda , François Grondin

Reliable quantification of natural and anthropogenic gas release (e.g.\ CO$_2$, methane) from the seafloor into the water column, and potentially to the atmosphere, is a challenging task. While ship-based echo sounders such as single beam…

Computer Vision and Pattern Recognition · Computer Science 2022-07-19 Mengkun She , Tim Weiß , Yifan Song , Peter Urban , Jens Greinert , Kevin Köser

We investigate the accretion process for different spherically symmetric space-time geometries for a static fluid. We analyse this procedure using the most general black hole metric ansatz. After that, we examine the accretion process for…

General Relativity and Quantum Cosmology · Physics 2015-10-30 Sebastian Bahamonde , Mubasher Jamil

Gigahertz acoustic streaming microjets, with the capability of achieving fluid speeds up to meters per second, open new avenues for precision fluid and particle manipulation at microscales. However, theoretical and numerical investigations…

Fluid Dynamics · Physics 2023-12-25 Michael Baudoin , Virginie Daru

The difference between "beating" and "pushing" results in the perception that a push just makes the object move as a whole, while a beat produces also a sound. Through a detailed analysis of the physics underlying such everyday experiences,…

Classical Physics · Physics 2020-01-08 Loris Ferrari