Acoustic characteristics

Continued part 1, part 2 of ebook "Seismic safety of high arch dams" includes the following main contents: Chapter 12 - The experimental research on the dynamic and static mechanical characteristics of dam concrete and the constitutive materials; Chapter 13 - Experimental study of dynamic and static damage failure of concrete dam based on acoustic emission technology; Chapter 14 - Testing research on large dam concrete dynamic-static damage and failure based on CT technology; Chapter 15 - Research on numerical analysis of full gradation large dam concrete dynamic behaviors;...

315p khuynhlinhnguyet1009 05-04-2024 3 1   Download

The purpose of study "Sustainable supply chain management in smart city design: A case study of Al Khobar city centre" is to analyze the impact of supply chain management (SCM) on smart city development. More specifically, we investigate the connections between smart cities, and supply network characteristics (supply network structure and governance mechanisms). Urban spaces, which have high acoustic quality, are a rare resource that must be protected to achieve the sustainable urban development as well as health and comfort of the urban space users.

18p longtimenosee07 29-03-2024 6 2   Download

This article presents an approach to build and verify a tool for calculating aerodynamic noise characteristics of helicopter rotors. The calculation tool is built on the basis of combining the vortex lattice method and the Formulation 1A of Farrasat, which is one of solutions of the Ffowcs Williams-Hawkings (FW-H) equation.

12p viengels 25-08-2023 3 2   Download

The results of synchronous detection of the emission of various components of the electromagnetic and acoustic fields obtained under conditions of low industrial interference and a high level of microseismicity are investigated. To compensate electromagnetic radiation of lithospheric origin, a compensation method was used.

6p vipagani 24-10-2022 4 3   Download

Honeycombing on high-resolution computed tomography (HRCT) is a distinguishing feature of usual interstitial pneumonia and predictive of poor outcome in interstitial lung diseases (ILDs). Although fine crackles are common in ILD patients, the relationship between their acoustic features and honeycombing on HRCT has not been well characterized.

8p vimaine2711 26-03-2021 6 2   Download

This is the first study that describes calls from this genus in Vietnam. Five acoustics parameters were measured, including call duration (s), call repetition rate (calls/s), inter-call interval(s), number of notes or pulses in a call, dominant frequency of call (kHz).

8p tamynhan9 02-12-2020 6 1   Download

AlN films were deposited on Si substrates using a reactive RF magnetron sputtering process and then the films were annealed by using different laser powers and wavelengths (355 nm, 532 nm and 1064 nm). For all three laser systems, the (002) peak intensity was obviously improved following laser irradiation.

6p vijiraiya2711 27-05-2020 14 1   Download

This article provides a method of acoustic emission (AE) technique to detect leakage in pipeline and locate the position of the leakage. The AE sensor is made of piezoelectric effect transducer to pick up the acoustic emission signal which is generated from the turbulent flow at the leak position.

8p tohitohi 19-05-2020 10 0   Download

The analytic results have shown that EC depends on temperature, magnetic field, characteristic quantities of EMW and m - quantum number which is specific the confined phonons in a complicated way. The numerical results for GaAs/GaAsAl quantum wells (QW) have displayed these dependence explicitly. In particular, when m is set to zero, we achieve results for magneto – thermoelectric effect in the same QW without the confinement of acoustic phonons.

7p queencongchua3 07-09-2019 23 4   Download

The study presented in this article is one of the attempts to find out whether adult learners can consistently distinguish unknown languages spoken by the same talker and thus whether they are subconsciously aware of the acoustic – phonetic characteristics of these languages in the pre-lexical stage of learning.

13p thiendiadaodien_5 08-01-2019 23 1   Download

The Hall effect is studied theoretically in a doped semiconductor superlattice (DSSL) subjected to a crossed dc electric field and magnetic field in the presence of an intense electromagnetic wave (EMW). By using the quantum kinetic equation for electrons interacting with acoustic phonons at low temperature, we obtain expressions for the magnetoresistance as well as the Hall coefficient in dependence on the external fields and characteristic parameters of the DSSL. Analytical results are numerically evaluated for the GaAs:Si/GaAs:Be DSSL.

6p thuyliebe 09-10-2018 49 0   Download

Brillouin scattering was discovered in 1922 by Louis Brillouin [1]. It is one of a number of characteristic scattering phenomena that occur when light interacts with solid, liquid or gaseous media and corresponds to the scattering of light from thermally-induced acoustical waves (propagating pressure/density waves) present in media at all temperatures. At normal light levels the amount of scattering is small. The characteristics of the scattering can offer interesting information about the properties of the medium (temperature, pressure) and form the basis for remote fibre sensor devices.

208p bachduong1311 07-12-2012 111 3   Download

In 2001 I was contacted by a consortium of research institutions and wind energy interests with a request to provide some background information on the operational characteristics of acoustic radars or SODARs. The consortium partners had set up and been funded for an European EU project to evaluate SODARs as a tool in monitoring wind flows at wind turbine sites. They felt reasonably confident in their knowledge of SODARs and had purchased some instruments, but wanted to be able to consult on any more complex issues which arose.

284p 951628473 07-05-2012 110 13   Download

CHAPTER 24 NOISE MEASUREMENT AND CONTROL George M. Diehl, RE. Consulting Engineer Machinery Acoustics Phillipsburg, New Jersey 24.1 24.2 24.3 24.4 24.5 24.6 24.7 SOUND CHARACTERISTICS FREQUENCY AND WAVELENGTH VELOCITYOFSOUND SOUND POWER AND SOUND PRESSURE DECIBELS AND LEVELS COMBINING DECIBELS 711 712 24.14 MACHINES IN SEMIREVERBERANT LOCATIONS TWO-SURFACE METHOD MACHINERYNOISE CONTROL SOUNDABSORPTION NOISE REDUCTION DUE TO INCREASED ABSORPTION IN ROOM SOUNDISOLATION SINGLEPANEL COMPOSITE PANEL ACOUSTICENCLOSURES 716 717 719 719 24.15 712 24.16 712 24.17 712 24.18 712 24.19 24.20 24.

18p hadalabo 29-09-2010 48 5   Download

ECHO CANCELLATION 14.1 14.2 14.3 14.4 14.5 14.6 14.7 Introduction: Acoustic and Hybrid Echoes Telephone Line Hybrid Echo Hybrid Echo Suppression Adaptive Echo Cancellation Acoustic Echo Sub-band Acoustic Echo Cancellation Summary cho is the repetition of a waveform due to reflection from points where the characteristics of the medium through which the wave propagates changes. Echo is usefully employed in sonar and radar for detection and exploration purposes. In telecommunication, echo can degrade the quality of service, and echo cancellation is an important part of communication systems.

20p khinhkha 30-07-2010 112 5   Download