The Effect of Soundproofing Materials on Sound Transmission
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All You Need to Know About SINAD Measurements Using the 2023
applicationapplication notenote All you need to know about SINAD and its measurement using 2023 signal generators The 2023A, 2023B and 2025 can be supplied with an optional SINAD measuring capability. This article explains what SINAD measurements are, when they are used and how the SINAD option on 2023A, 2023B and 2025 performs this important task. www.ifrsys.com SINAD and its measurements using the 2023 What is SINAD? C-MESSAGE filter used in North America SINAD is a parameter which provides a quantitative Psophometric filter specified in ITU-T Recommendation measurement of the quality of an audio signal from a O.41, more commonly known from its original description as a communication device. For the purpose of this article the CCITT filter (also often referred to as a P53 filter) device is a radio receiver. The definition of SINAD is very simple A third type of filter is also sometimes used which is - its the ratio of the total signal power level (wanted Signal + unweighted (i.e. flat) over a broader bandwidth. Noise + Distortion or SND) to unwanted signal power (Noise + The telephony filter responses are tabulated in Figure 2. The Distortion or ND). It follows that the higher the figure the better differences in frequency response result in different SINAD the quality of the audio signal. The ratio is expressed as a values for the same signal. The C-MES signal uses a reference logarithmic value (in dB) from the formulae 10Log (SND/ND). frequency of 1 kHz while the CCITT filter uses a reference of Remember that this a power ratio, not a voltage ratio, so a 800 Hz, which results in the filter having "gain" at 1 kHz. -
New ELBRIGHT TOSHIBA HIGH SPEED ELEVATORS Concept of New ELBRIGHT
New ELBRIGHT TOSHIBA HIGH SPEED ELEVATORS Concept of New ELBRIGHT New ELBRIGHT CONTENTS ●New ELBRIGHT Machine-Room TOSHIBA HIGH SPEED ELEVATORS PRODUCT CONCEPT New technology planning/Group control system Traffic New ELBRIGHT A new concept in high-speed elevators. Elevator technology ·· ❸~❹ Toshiba never stops introducing the latest tech- nologies and polishing its high-speed elevator expertise. Toshiba proves this again with THE GUIDE LINE-1 New ELBRIGHT : a new elevator for a new age. Traffic planning / Group control system ·· ❺~❽ Toshiba engineering has combined to produce the 1-1 Deciding speed ········ ❻ world’s first inverter-control high-speed elevator, SPACE SAVING 1-2 Deciding number of cars ········ ❻ 1-3 Deciding passenger capacity ········ ❼ with the high-efficiency control, energy efficiency, ●Conventional type up to 50% reduction 1-4 Deciding service floors ········ ❼ elevator machine-room in machine room space and quiet operation demanded by today’s society. 1-5 Deciding the layout ········ ❼ 1-6 Operating system ········ ❽ 1-7 Group control system (EJ-1000series) ········ ❽ Soundproofing and harmonic distortion measures THE GUIDE LINE-2 Providing environmentally conscious products (New ELBRIGHT) Toshiba elevator group is promoting the development of environmentally Soundproofing and conscious products, which involves environmentally conscious product design, harmonic distortion the assessment of environmental impact of products and disclosure of the measures ·· 10~14 environmental performance of products. Products are developed -
AN279: Estimating Period Jitter from Phase Noise
AN279 ESTIMATING PERIOD JITTER FROM PHASE NOISE 1. Introduction This application note reviews how RMS period jitter may be estimated from phase noise data. This approach is useful for estimating period jitter when sufficiently accurate time domain instruments, such as jitter measuring oscilloscopes or Time Interval Analyzers (TIAs), are unavailable. 2. Terminology In this application note, the following definitions apply: Cycle-to-cycle jitter—The short-term variation in clock period between adjacent clock cycles. This jitter measure, abbreviated here as JCC, may be specified as either an RMS or peak-to-peak quantity. Jitter—Short-term variations of the significant instants of a digital signal from their ideal positions in time (Ref: Telcordia GR-499-CORE). In this application note, the digital signal is a clock source or oscillator. Short- term here means phase noise contributions are restricted to frequencies greater than or equal to 10 Hz (Ref: Telcordia GR-1244-CORE). Period jitter—The short-term variation in clock period over all measured clock cycles, compared to the average clock period. This jitter measure, abbreviated here as JPER, may be specified as either an RMS or peak-to-peak quantity. This application note will concentrate on estimating the RMS value of this jitter parameter. The illustration in Figure 1 suggests how one might measure the RMS period jitter in the time domain. The first edge is the reference edge or trigger edge as if we were using an oscilloscope. Clock Period Distribution J PER(RMS) = T = 0 T = TPER Figure 1. RMS Period Jitter Example Phase jitter—The integrated jitter (area under the curve) of a phase noise plot over a particular jitter bandwidth. -
How to Soundproof Light Aircraft
1 October 2004 Introduction We first put these ideas down in 1990, in the form of an instruction sheet that we handed out with Super Sound Proofing foam mat. Over the years we’ve expanded them, mostly by feedback from users of the product and have printed thousands of these little booklets. You are invited to pass back your experiences‘ with this and the other products that have been added to our arsenal in the fight against noise. We now have acoustical foam materials to be used in Boats, Trucks and Cars as well as new materials used in Architectural applications for home wall a& ceilings, sound studios, gyms, industrial as well as for band practice in the garage! Our specialty is aircraft applications as it is the most challenging! We are always available for free consulting at anytime for any application, to help you with what we know about methods and materials for sound- proofing. We’ll provide free copies of this booklet to groups and Associations; just let us know how many you need. The latest version of this manual is available from our website at http://soundproofing.org/infopages/soundprf.html © Copyright 1998/2002/2004 by Bill Nash - all rights reserved. Reprint rights granted when full credit is given. 2 Logbook Certification letter: SUPER SOUNDPROOFING CO P.O. Box 985 Vista CA 92085 (760) 752-3030 October I3, 2004 RE: FAA CERTIFICATION OF “SUPER SOUNDPROOFING” MATERIAL To Whom it May Concern: This letter provides information regarding Super Soundproofing Material for which we are the mill distributors. This letter is to certify the material has FAA approval obtained by testing at a FAA approved lab. -
Recent Advances in the Sound Insulation Properties of Bio-Based Materials
PEER-REVIEWED REVIEW ARTICLE bioresources.com Recent Advances in the Sound Insulation Properties of Bio-based Materials Xiaodong Zhu,a,b Birm-June Kim,c Qingwen Wang,a and Qinglin Wu b,* Many bio-based materials, which have lower environmental impact than traditional synthetic materials, show good sound absorbing and sound insulation performances. This review highlights progress in sound transmission properties of bio-based materials and provides a comprehensive account of various multiporous bio-based materials and multilayered structures used in sound absorption and insulation products. Furthermore, principal models of sound transmission are discussed in order to aid in an understanding of sound transmission properties of bio-based materials. In addition, the review presents discussions on the composite structure optimization and future research in using co-extruded wood plastic composite for sound insulation control. This review contributes to the body of knowledge on the sound transmission properties of bio-based materials, provides a better understanding of the models of some multiporous bio-based materials and multilayered structures, and contributes to the wider adoption of bio-based materials as sound absorbers. Keywords: Bio-based material; Acoustic properties; Sound transmission; Transmission loss; Sound absorbing; Sound insulation Contact information: a: Key Laboratory of Bio-based Material Science and Technology (Ministry of Education), Northeast Forestry University, Harbin 150040, China; b: School of Renewable Natural Resources, LSU AgCenter, Baton Rouge, Louisiana; c: Department of Forest Products and Biotechnology, Kookmin University, Seoul 136-702, Korea. * Corresponding author: [email protected] (Qinglin Wu) INTRODUCTION Noise reduction is a must, as noise has negative effects on physiological processes and human psychological health. -
Signal-To-Noise Ratio and Dynamic Range Definitions
Signal-to-noise ratio and dynamic range definitions The Signal-to-Noise Ratio (SNR) and Dynamic Range (DR) are two common parameters used to specify the electrical performance of a spectrometer. This technical note will describe how they are defined and how to measure and calculate them. Figure 1: Definitions of SNR and SR. The signal out of the spectrometer is a digital signal between 0 and 2N-1, where N is the number of bits in the Analogue-to-Digital (A/D) converter on the electronics. Typical numbers for N range from 10 to 16 leading to maximum signal level between 1,023 and 65,535 counts. The Noise is the stochastic variation of the signal around a mean value. In Figure 1 we have shown a spectrum with a single peak in wavelength and time. As indicated on the figure the peak signal level will fluctuate a small amount around the mean value due to the noise of the electronics. Noise is measured by the Root-Mean-Squared (RMS) value of the fluctuations over time. The SNR is defined as the average over time of the peak signal divided by the RMS noise of the peak signal over the same time. In order to get an accurate result for the SNR it is generally required to measure over 25 -50 time samples of the spectrum. It is very important that your input to the spectrometer is constant during SNR measurements. Otherwise, you will be measuring other things like drift of you lamp power or time dependent signal levels from your sample. -
Image Denoising by Autoencoder: Learning Core Representations
Image Denoising by AutoEncoder: Learning Core Representations Zhenyu Zhao College of Engineering and Computer Science, The Australian National University, Australia, [email protected] Abstract. In this paper, we implement an image denoising method which can be generally used in all kinds of noisy images. We achieve denoising process by adding Gaussian noise to raw images and then feed them into AutoEncoder to learn its core representations(raw images itself or high-level representations).We use pre- trained classifier to test the quality of the representations with the classification accuracy. Our result shows that in task-specific classification neuron networks, the performance of the network with noisy input images is far below the preprocessing images that using denoising AutoEncoder. In the meanwhile, our experiments also show that the preprocessed images can achieve compatible result with the noiseless input images. Keywords: Image Denoising, Image Representations, Neuron Networks, Deep Learning, AutoEncoder. 1 Introduction 1.1 Image Denoising Image is the object that stores and reflects visual perception. Images are also important information carriers today. Acquisition channel and artificial editing are the two main ways that corrupt observed images. The goal of image restoration techniques [1] is to restore the original image from a noisy observation of it. Image denoising is common image restoration problems that are useful by to many industrial and scientific applications. Image denoising prob- lems arise when an image is corrupted by additive white Gaussian noise which is common result of many acquisition channels. The white Gaussian noise can be harmful to many image applications. Hence, it is of great importance to remove Gaussian noise from images. -
AN10062 Phase Noise Measurement Guide for Oscillators
Phase Noise Measurement Guide for Oscillators Contents 1 Introduction ............................................................................................................................................. 1 2 What is phase noise ................................................................................................................................. 2 3 Methods of phase noise measurement ................................................................................................... 3 4 Connecting the signal to a phase noise analyzer ..................................................................................... 4 4.1 Signal level and thermal noise ......................................................................................................... 4 4.2 Active amplifiers and probes ........................................................................................................... 4 4.3 Oscillator output signal types .......................................................................................................... 5 4.3.1 Single ended LVCMOS ........................................................................................................... 5 4.3.2 Single ended Clipped Sine ..................................................................................................... 5 4.3.3 Differential outputs ............................................................................................................... 6 5 Setting up a phase noise analyzer ........................................................................................................... -
Measuring Thriving Experience in Physical Working Spaces
Measuring Thriving Experience in Physical Working Spaces Yasmin Fathy† Erika A. Pärn† Denise J Wilkins†‡ Mohamed Zaki† †University of Cambridge, UK ‡Microsoft Research, Cambridge, UK {yafa2, eap47, mehyz2}@cam.ac.uk [email protected] ABSTRACT boosts their creativity and productivity while being in sur- The global pandemic has enforced corporations to shift into roundings that signal the brand of their chosen employers. new working patterns and design upgrades of the physical Employers are simultaneously expected to provide emotional working space - from packed desks to long-term modifica- support and help maintain the well-being of their employees. tions design, putting well-being at the heart of workplace Technology has empowered design of physical remote work- planning. This paper hypothesises the use of technologies to ing spaces - from collaboration tools such as Trello to com- revolutionise work practices for monitoring the well-being in a munication applications such as Slack and Microsoft Teams. physical space. New human-computer interaction approaches However, it does not determine the level of social engagement can be introduced to measure psychophysical and physical or capturing employees’ emotional states. When working with metrics to gauge occupant thriving in indoor office environ- such technologies, employees often choose their verbal and ments. They offer changes to the working environment, e.g. cognitive level of engagement. breaks and lighting to enhance productivity and well-being. This research investigates three domains to measure human The lock-down period has also been recorded to have cre- thriving indoor: (a) methods used in architecture domain to ated a long-term socioeconomic impact and increased the understand the impact of architecture design on human thriv- prevalence of mental health issues. -
Active Noise Control Over Space: a Subspace Method for Performance Analysis
applied sciences Article Active Noise Control over Space: A Subspace Method for Performance Analysis Jihui Zhang 1,* , Thushara D. Abhayapala 1 , Wen Zhang 1,2 and Prasanga N. Samarasinghe 1 1 Audio & Acoustic Signal Processing Group, College of Engineering and Computer Science, Australian National University, Canberra 2601, Australia; [email protected] (T.D.A.); [email protected] (W.Z.); [email protected] (P.N.S.) 2 Center of Intelligent Acoustics and Immersive Communications, School of Marine Science and Technology, Northwestern Polytechnical University, Xi0an 710072, China * Correspondence: [email protected] Received: 28 February 2019; Accepted: 20 March 2019; Published: 25 March 2019 Abstract: In this paper, we investigate the maximum active noise control performance over a three-dimensional (3-D) spatial space, for a given set of secondary sources in a particular environment. We first formulate the spatial active noise control (ANC) problem in a 3-D room. Then we discuss a wave-domain least squares method by matching the secondary noise field to the primary noise field in the wave domain. Furthermore, we extract the subspace from wave-domain coefficients of the secondary paths and propose a subspace method by matching the secondary noise field to the projection of primary noise field in the subspace. Simulation results demonstrate the effectiveness of the proposed algorithms by comparison between the wave-domain least squares method and the subspace method, more specifically the energy of the loudspeaker driving signals, noise reduction inside the region, and residual noise field outside the region. We also investigate the ANC performance under different loudspeaker configurations and noise source positions. -
22Nd International Congress on Acoustics ICA 2016
Page intentionaly left blank 22nd International Congress on Acoustics ICA 2016 PROCEEDINGS Editors: Federico Miyara Ernesto Accolti Vivian Pasch Nilda Vechiatti X Congreso Iberoamericano de Acústica XIV Congreso Argentino de Acústica XXVI Encontro da Sociedade Brasileira de Acústica 22nd International Congress on Acoustics ICA 2016 : Proceedings / Federico Miyara ... [et al.] ; compilado por Federico Miyara ; Ernesto Accolti. - 1a ed . - Gonnet : Asociación de Acústicos Argentinos, 2016. Libro digital, PDF Archivo Digital: descarga y online ISBN 978-987-24713-6-1 1. Acústica. 2. Acústica Arquitectónica. 3. Electroacústica. I. Miyara, Federico II. Miyara, Federico, comp. III. Accolti, Ernesto, comp. CDD 690.22 ISBN 978-987-24713-6-1 © Asociación de Acústicos Argentinos Hecho el depósito que marca la ley 11.723 Disclaimer: The material, information, results, opinions, and/or views in this publication, as well as the claim for authorship and originality, are the sole responsibility of the respective author(s) of each paper, not the International Commission for Acoustics, the Federación Iberoamaricana de Acústica, the Asociación de Acústicos Argentinos or any of their employees, members, authorities, or editors. Except for the cases in which it is expressly stated, the papers have not been subject to peer review. The editors have attempted to accomplish a uniform presentation for all papers and the authors have been given the opportunity to correct detected formatting non-compliances Hecho en Argentina Made in Argentina Asociación de Acústicos Argentinos, AdAA Camino Centenario y 5006, Gonnet, Buenos Aires, Argentina http://www.adaa.org.ar Proceedings of the 22th International Congress on Acoustics ICA 2016 5-9 September 2016 Catholic University of Argentina, Buenos Aires, Argentina ICA 2016 has been organised by the Ibero-american Federation of Acoustics (FIA) and the Argentinian Acousticians Association (AdAA) on behalf of the International Commission for Acoustics. -
ASI-Products-Brochure-4484329 | Acoustical Surfaces, Inc
Acoustical Surfaces, Inc. Soundproofing & Acoustical Products 888888..225577..22664433 wwwwww..aaccoouussttiiccaallssuurrffaacceess..ccoomm Echo Eliminator™ Sound Silencer™ Bonded Acoustical Cotton Panels Porous Expanded Polypropylene (P.E.P.P.) Acoustical Panels cho Eliminator is a high performance acous- Product Features: ound Silencer acoustical wall panels and Product Features: tical material made from recycled cotton. Recycled cotton ceiling tiles are an entirely new kind o f Class A Fire Rated EThis product is ideal for noise control applica - ▶Class A Fire Rated Sacoustical panel. Made from Porous Expanded ▶No fiberglass tions. Echo Eliminator can be used as acoustical ▶Lightweight Polypropylene (P .E.P .P.), these panels are Class ▶Moisture resistant (indoor) wall panels or hanging baffles. A fire rated and have both STC and NRC values. ▶Easy to install (adhesive application) ▶Non-fibrous Common applications are school gyms, class - ▶Impact resistant They are tackable, lightweight, and bacteria ▶Impact resistant rooms, lunch rooms, community centers and and fungi resistant. Sound Silencer panels ▶Durable ▶Non-abrasive surface any application where a high performance are great for gymnasiums, ice rinks, swimming ▶Low cost ▶Both STC & NRC ratings noise control product is needed. pools, clean rooms, laboratories, food prepara - ▶High light reflectance ▶Tackable surface Echo Eliminator may contribute to LEED ® credits, ti on areas and anywhere else where noise ▶ ▶ is Class A fire rated and 100% recyclable. It has High performance acoustical absorption control is important. Panels can be applied Bacteria & fungi resistant ▶ ▶ no VOC's, no formaldehyde and requires no Relocatable (with grommets) directly on wall and ceiling surfaces for attractive Lightweight warning labels. It is also fungi, mold, and ▶ and effective sound control.