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The rapid development of electromobility is placing ever higher demands on new electric motor designs. This results in a gradual reduction in weight with a simultaneous increase in maximum torque. As a result, unfavorable phenomena, such as vibration and noise, can become apparent in the drivetrain. Modeling and evaluation of the acoustic noise sources of a traction motor are particularly important when it is used, for example, as the traction drive of an electric bus, where too high noise levels can have a negative impact on passengers. This article describes methods for analyzing and evaluating the root causes of noise that occurs in permanent magnet traction motors with a rotor in which the magnets have been placed inside the rotor (PMSM IPM). This paper presents an analysis of acoustic noise and forces acting in the air gap of a 240 kW motor with 60 stator slots and 2p = 10 (s60p20) as the number of pole pairs designed for bus and truck drives. To determine the dominant noise sources and evaluate their value, the forces acting in the air gap and their effect on the deflection of the outer surface of the stator yoke were calculated. The natural frequencies of the machine, their frequencies for the entire rotor speed range, and the frequency of vibration of the motor stator were calculated. Based on these data, the sound power level (A-SWL) was calculated at varying motor speeds. MANATEE software (EOMYS, 9, avenue de la Créativité, 59650 Villeneuve d'Ascq—FRANCE) from EOMYS was used to perform vibroacoustic calculations. The analysis results were also subjected to verification on a laboratory bench. [ABSTRACT FROM AUTHOR]

The article discusses the highlights of the Eurocorr conference held at the Acropolis Convention Centre in Nice, France from September 6-10, 2010. The event featured technical sessions about inhibitors, oil and gas and polymeric materials and metallic, as well as inorganic coatings and pretreatment. One of the paper presented in the session titled "New Tools to Evaluate Electrochemical Noise Data," was given by Günter Schmitt. Particular focus is given to a keynote presentation by Yurii Kuznetsov of the Russian Academy of Sciences.

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Previous work suggested a method that makes use of the Zwicker's loudness value of transmitted sound to validate single number quantities (SNQs) determining the airborne sound insulation of walls in dwellings. The correlation between the ranking of walls based on a SNQ, and the one based on transmitted sound loudness was used to qualify the adequacy of that SNQ. The underlying idea is that Zwicker's loudness adequately represents people's perception of loudness and that evaluations based on calculated loudness can substitute listening tests. The current work compares 16 SNQs: eight standardized or proposed in past studies, and eight new ones. The results are more robust, since more (56) walls were included, among which also highly isolating ones. SNQs are assessed for the indoor noise stimulus recently suggested by CSTB, France, and also for four filtered variants, and for two levels, the 'usual' or 'normal' level (as reported by CSTB), and that level increased by 10 dB, expressing the less common but psychologically and socially relevant situation of excessive neighbour noise. The adequacy of SNQs is analysed per wall category, (1) lightweight, (2) heavyweight, (3) CLT-based and (4) combined walls and per stimulus type. Three approaches are used to quantify the correlation between SNQ-based wall insulation performance rankings and Loudness based ones: (i) Spearman's correlation coefficient, (ii) correlation and (iii) inverse RMS residual of fitting with a parametrized function that has been empirically conceived so as to describe as good as possible the correlation SNQ-Loudness correlation behaviour for the considered population of walls. [ABSTRACT FROM AUTHOR]

Construction site noise significantly contributes to urban noise pollution. To accurately assess the noise exposure from urban construction sites, it is essential to consider the variability and dynamic nature of the urban context. This paper proposes an innovative approach using individual-level activity-based modeling to tackle the given challenge. The methodology introduced encompasses: the modeling of construction site noise emission sources, individual-level activity-based modeling of zone of influences, a modeling chain for assessing individual noise exposure levels, and a novel dedicated exposure indicator. To illustrate the relevance of our methodology, a case study is conducted in Champigny-sur-Marne, France; this study involves the generation of a synthetic population of 1,344,394 individuals distributed among 591,153 households, with 4,854,597 associated activities, using the Eqasim simulation framework. A traffic model is then established using the multi-agent transport simulation software MATSim. NoiseModelling software is employed to compute noise maps both with and without the construction site. Subsequently, the noise exposure for each individual is assessed throughout the day for both configurations. Thanks to this complete modeling chain, the proposed indicator quantifying the cumulative amount of time of exposure above a given threshold can be compute, with the case study result being estimated at more than 3,300 person.quarter-hours above 65 dB(A). • Original methodology for accurate and detailed assessment of exposure to urban construction site noise. • Disaggregated activity-based modeling of the urban environment. • Comprehensive modeling chain for computing individual noise exposure. • Introduction of a novel indicator for evaluating exposure to urban construction site noise. • Illustration of the methodology with a case study in France. [ABSTRACT FROM AUTHOR]

The fabrication of 3D detectors which requires bulk micromachining of columnar electrodes has been realized with advancements in MEMS technology. Since the fabrication of the first 3D prototype in Stanford Nanofabrication Facility in 1997, a significant effort has been put forth to transfer the 3D detector technology to large scale manufacturing for future high luminosity collider experiments, in which the radiation hardness will be the primary concern, and other applications such as medical imaging and X-ray imaging for molecular biology. First, alternative 3D structures, single type column (STC) and double-side double type column (DDTC) 3D detectors, were produced at FBK-irst (Trento, Italy) and CNM-Barcelona (Spain), and assessed thoroughly to improve the production technology towards the standard full-3D detectors. The 3D collaboration has been extended to include SINTEF (Norway), which is committed to small to medium scale production of active edge full-3D silicon sensors. This paper focuses on p-type 3D detectors compatible with the CMS pixel front end electronics from the second run of fabrication at SINTEF clean room facilities. The sensors that passed the wafer level electrical characterization have been bump-bonded at IZM (Germany), assembled into modules and wire-bonded for functional characterization at Purdue University. We report the leakage current characteristics, bump-bond quality, threshold, noise, and gain measurement results of these 3D modules as well as the preliminary beam test data taken at Fermi National Accelerator Laboratory. [ABSTRACT FROM AUTHOR]

SUMMARY: The local ground motion amplification related to the geology at a specific site (i.e. the so-called site effects) may be classically quantified through the SSR (standard spectral ratio) technique applied on earthquake recordings. However, such a quantification might be challenging to carry out in low-to-moderate seismicity regions. Methods based on background ambient noise, such as noise-based standard spectral ratio (SSRn), might be of great interest in these areas. But noise-derived amplification is particularly sensitive to local anthropogenic sources, which may introduce biases in the evaluation of site effects by dominating the geological effects, especially for frequencies higher than 1 Hz. A hybrid approach (SSRh), developed to reduce biases in noise-based spectral ratios by combining classical earthquake-based spectral ratio (SSR) and SSRn, was recently introduced and relies on a site reference. We here investigate the applicability of SSRn and SSRh in a heavily industrialized environment in the Tricastin Valley (south-east France), where critical facilities are located. We continuously recorded ambient noise from 2020 February to March on a 400-sensor seismic array covering an area of about 10 km by 10 km. We demonstrate that SSRn and SSRh computed below 1 Hz are able to reproduce amplification factors provided by SSR. By contrast, at frequencies higher than 1 Hz, SSRn strongly deviates from SSR. SSRh shows closer results to SSR but presents a dependence to the choice of the local site reference, thereby questioning the possibility to use SSRh blindly to estimate the local amplification in our context. These discrepancies reflect the impact of local anthropogenic sources. We therefore introduced a two-step workflow to mitigate the influence of local sources. The first step is to define a characteristic time window to optimally isolate significant transient signals. The second step consists in selecting the time segments that do not contain these transients with a clustering-based approach. By applying this workflow, we were able to remove some strong anthropogenic transient signals likely to be generated by local sources at some sites and therefore to locally improve the amplification assessment through noise-based spectral ratios. However, stationary sources, whose impact cannot be removed through our procedure, remain a major issue. This study provides some insights into the application of SSRn and SSRh in noisy industrialized areas, especially regarding the impact of local noise sources. It illustrates the difficulty of having a procedure for mitigating the impact of these sources that is efficient everywhere inside such a complex anthropized environment, where different types of sources (including stationary sources) cohabit. [ABSTRACT FROM AUTHOR]

This study was aimed at assessing listening effort (LE) in quiet and in noisy daily life situations, in 481 adults with hearing aids (HAs) and 62 adults with normal hearing, using an Extended version of the Effort Assessment Scale (EEAS). Participants were invited to self-assess their LE in daily life, on a visual analog scale graded from 0 (no effort) to 10. The EEAS's internal structure identified two separate constructs pertaining to LE in quiet and LE in noise, each with good consistency (Cronbach's a > 0.83). A three-factor model explained 12% of the variance of the EEAS scores, with HA experience the most important one, and better ear hearing threshold (averaged across 0.5-4 kHz) and ear asymmetry as the other two factors. The EEAS subscales differed in behavior, with the LE in noise being the most dependent on HA experience, whereas LE in quiet depended more on better ear hearing threshold. In a subgroup of people with 6 months to less than 24 months HA experience, a significant decrease in LE in noise was observed with increasing HA experience (0.26 points decrease per year of HA experience), whereas in a group of people with at least 24 months of HA experience, a small increase in LE in noise was observed. This effect was not mediated by age, nor hearing threshold. The extended Effort Assessment Scale is therefore offering an assessment of both LE in quiet and LE in noise, with different dependence on HA experience and hearing thresholds. [ABSTRACT FROM AUTHOR]

Decreased speech-in-noise (SpIN) understanding is an early marker not only of presbycusis but also of auditory processing disorder. Previous research has shown a strong relationship between hearing disorders and cognitive limitations. It is therefore crucial to allow SpIN testing in subjects who cannot sustain prolonged diagnostic procedures. The objectives of this study were to develop a rapid and reproducible version of the Hearing in Noise Test (HINT-5 min), and to determine its adult normative values in free-field and monaural or binaural headphone conditions. Following an adaptive signal-to-noise ratio (SNR) protocol, the test used a fixed noise level, while the signal level varied to reach the 50% speech reception threshold (SRT50). The speech material consisted of five lists of 20 sentences each, all recorded in European French. The whole semi-automated procedure lasted 5 min and was administered to 83 subjects aged 19 to 49 years with no reported listening difficulties. Fifty-two subjects were retested between 7 and 8 days later. For the binaural free-field condition, the mean SRT50 was −1.0 dB SNR with a standard deviation of 1.3 dB SNR. There was no significant difference between the results obtained at test and retest, nor was there any effect of listening condition, sex, or age on SRT50. The results indicate that the procedure is robust and not affected by any learning phenomenon. The HINT-5 min was found to be both a fast and reliable marker of the ability to understand speech in background noise. [ABSTRACT FROM AUTHOR]

This study is a metrological investigation of eight superconducting gravimeters that have operated in the Strasbourg gravimetric Observatory. These superconducting gravimeters include an older compact C026 model, a new observatory type iOSG23 and six iGravs (6, 15, 29, 30, 31, 32). We first compare the amplitude calibration of the meters using measurements from FG5 #206 absolute gravimeter (AG). In a next step we compute the amplitude calibration of all the meters by time regression with respect to iOSG23 itself carefully calibrated by numerous AG experiments. The relative calibration values are much more precise than absolute calibration for each instrument and strongly reduce any tidal residual signal. We also compare the time lags of the various instruments with respect to iOSG23, either by time cross-correlation or tidal analysis for the longest records (about 1 year). The instrumental drift behavior of the iGravs and iOSG23 is then investigated and we examine the relationships observed between gravity and body temperature measurements. Finally, we compare the noise levels of all the instruments. A three-channel correlation analysis is used to separate the incoherent (instrumental) noise from the coherent (ambient) noise. The self-noise is then compared to a model of thermal noise (Brownian motion) using the known instrumental parameters of the damped harmonic oscillator. The self-noise of iGrav instruments is well-explained by the thermal noise model at seismic frequencies (between 10–3 and 10–2 Hz). As expected, the self-noise of iOSG23 with a heavier sphere is also lower than that of iGravs at such frequencies. [ABSTRACT FROM AUTHOR]

As part of the Agence Nationale de Recherche Caractérisation des ENvironnements SonorEs urbains (Characterization of urban sound environments) project, a questionnaire was sent in January 2019 to households in a 1 km2 study area in the city of Lorient, France, to which about 318 responded. The main objective of this questionnaire was to collect information about the inhabitants' perception of the sound environments in their neighborhoods, streets, and dwellings. In the same study area, starting mid-2019, about 70 sensors were continuously positioned, and 15 of them were selected for testing sound source recognition models. The French lockdown due to the COVID-19 crisis occurred during the project, and the opportunity was taken to send a second questionnaire during April 2020. About 31 of the first 318 first survey respondents answered this second questionnaire. This unique longitudinal dataset, both physical and perceptual, allows the undertaking of an analysis from different perspectives of such a period. The analysis reveals the importance of integrating source recognition tools, soundscape observation protocol, in addition to physical level analysis, to accurately describe the changes in the sound environment. [ABSTRACT FROM AUTHOR]

Abstract: A major luminosity upgrade for the Large Hadron Collider (LHC) proton–proton collider at CERN is planned for to allow for peak luminosities of . The current inner tracker of the ATLAS experiment will be completely replaced to guarantee excellent tracking capabilities in an environment characterized by much higher detector occupancies and harsher radiation backgrounds as compared with the current LHC. The new tracker will be an all-silicon based system, with pixel detectors in the innermost layers and silicon micro-strip layers at outer radii. The so-called super-module concept is an integration solution proposed for the strip barrel region of the future ATLAS internal tracker. It consists of several double-sided silicon micro-strip modules assembled into a common light-weight support structure. A first electrical prototype of a super-module has been produced, aimed to exercise the readout chain and to investigate the noise performance of such a complex system. In this paper the super-module prototype is described and first electrical results are presented. [Copyright &y& Elsevier]

Abstract: Our consortium CESR-LAAS in Toulouse has developed generic technology for Geiger-APD and SiPM. The main feature of these devices is the high homogeneity in breakdown voltage. The work presented here describes the model that has been used to design these devices. This also includes the integration into micro-systems, with the ambition in the long term, to develop multiple applications in astrophysics, biology, optical sensing, and above all, imaging systems. The paper is divided as follows: [1.] An introduction presents the main issues in the physics of silicon avalanche Geiger mode systems. [2.] A section (Geiger mode) divided into two parts. The first part is devoted to the electrical model of the basic device, which provides the response of the Geiger-APD to an incident photon: gain, current, and voltage. The second part presents the production of the model using Simplorer simulation software under VHDL-AMS (VHSIC—Very High Speed Integrated Circuit-Hardware Description Language-Analog and Mixed Signal) . [3.] A comparison between our model and that used by Otono et al. followed by a discussion with a special emphasis on presenting the noise model based on the real component made and tested by our consortium. [4.] A conclusion. [ABSTRACT FROM AUTHOR]

A study of the impact of reverberation on cruise regime acoustic testing of contra-rotating open rotors in a wind tunnel is presented. Models for the rotor tone noise generated in closed cross-section wind tunnels are derived and used in the analysis. The models account for rectangular and circular cross-sections, rigid or impedance boundaries and, for the rectangular wind tunnel case, the rotor axis may be arbitrarily located within the tunnel (but aligned with the flow direction). These models are used to generate simple simulations of model-scale open rotor testing in two real wind tunnels suited to high-speed rotor testing – the Transonic Wind Tunnel in Bedford, UK and the S1MA wind tunnel in Modane, France. In the analysis, the effect of various modelling parameters on the reverberant noise field is investigated. It is shown that open rotor interaction tone noise may be particularly susceptible to the impact of reverberation and that for many tones the reverberant field may persist and contribute to a contaminated noise field, even for wind tunnels with acoustic treatments on the walls of the working section. [ABSTRACT FROM AUTHOR]

Open-plan offices account for 60% of French office workspaces. The noise levels recorded in this type of environment are much lower than those encountered in industrial workplaces. Nevertheless, surveys show that noise is considered by employees as the main source of discomfort. A first questionnaire dedicated to noise discomfort was produced in 2013 and tested on a panel made up of 217 people working in 7 French companies. Today, it also makes it possible to address the issues of fatigue related to ambient sound, but above all, the survey aims to study the differences in how ambient noise is perceived depending on the type of open-plan office. On the basis of that new version, a second survey has been conducted in 23 open-plan offices, making it possible to collect the responses from 617 employees. Most of the results of the first survey have been confirmed, with an increase in the significance of the statistical analyses. Moreover, French Standard NF S 31-199, which is currently being drafted, establishes a typology of open-plan office spaces according to the types of work done in them. Based on this typology, it appears that when dealing with the impact on noise on workers, a distinction has to be made between the types of open plan offices. Practitioner Summary:Surveys conducted in open-plan offices show that noise is considered by employees as the main source of discomfort even if the noise recorded in this type of environment is not hazardous. This work presents the result of a large survey dedicated to noise discomfort conducted in 23 open-plan offices. [ABSTRACT FROM AUTHOR]

Abstract: The Semi-Conductor Tracker (SCT) has been built and installed into the ATLAS detector at the Large Hadron Collider (LHC) in CERN. Together with the Pixel and Transition Radiation Tube (TRT) detectors it will provide precise tracking and vertexing information for the ATLAS Physics program. In this paper we report on the status, operational experience, and performance of the SCT in the run up to the start of the LHC. [Copyright &y& Elsevier]

Objective: To compare results on the everyday sentence test 'FIST', the new closed-set sentence test 'FrMatrix', and the digit triplet screening test 'FrDigit3'. Design: First, the FrMatrix was developed and normative values were obtained. Subsequently, speech reception thresholds (SRTs) for the three types of tests were gathered at four study centers representing different geographic regions in Belgium and France. Study sample: Fifty-seven normal-hearing listeners took part in the normative study of the FrMatrix, and 118 subjects, with a wide range of hearing thresholds, participated in the comparative study. Results: Homogenizing the individual words of the FrMatrix with regard to their intelligibility resulted in a reference SRT of −6.0 (±0.6) dB SNR and slope at the SRT of 14.0 %/dB. The within-subject variability was only 0.4 dB. Comparison of the three tests showed high correlations between the SRTs mutually (>0.81). The FrMatrix had the highest discriminative power, both in stationary and in fluctuating noise. For all three tests, differences across the participating study centers were small and not significant. Conclusions: The FIST, the FrMatrix, and the FrDigit3 provide similar results and reliably evaluate speech recognition performance in noise both in normal-hearing and hearing-impaired listeners. [ABSTRACT FROM AUTHOR]

The upgrade of the Large Hadron Collider (LHC) experiments at CERN sets new challenges for the powering of the detectors. One of the powering schemes under study is based on DC-DC buck converters mounted on the front-end modules. The hard environmental conditions impose strict restrictions to the converters in terms of low volume, radiation and magnetic field tolerance. Furthermore, the noise emission of the switching converters must not affect the performance of the powered systems. A study of the sources and paths of noise of a synchronous buck converter has been made for identifying the critical parameters to reduce their emissions. As proof of principle, a converter was designed following the PCB layout considerations proposed and then used for powering a silicon strip module prototype for the ATLAS upgrade, in order to evaluate their compatibility. [ABSTRACT FROM AUTHOR]

Reports on the International INCE Symposium to be held in Le Mans, France, June 27-29, 2005, concerning the problems of uncertainties in the field of noise and vibration through formal papers and discussions between all relevant players. Organizers of the event; Web site of the symposium.