WorldWideScience

Sample records for sound power levels

  1. Use of existing standards to measure sound power levels of powered hand tools-necessary revisions

    Science.gov (United States)

    Hayden, Charles S.; Zechmann, Edward

    2005-09-01

    At recent NOISE-CON and Acoustical Society of America meetings, noise rating labeling was discussed as a way of manufacturers providing full disclosure information for their noise emitting products. The first step is to gather sound power level data from these products. Sound power level data should be gathered in accordance with existing ANSI and/or ISO standards. Some standards, such as ANSI 12.15, may not define true operational noise emissions[r1] and thus may provide inaccurate information when that information is used to choose a hearing protection device or used to make a purchasing decision. A number of standards were systematically combined by NIOSH researchers to provide the most accurate information on sound power levels of powered hand tools used in the construction industry. This presentation will detail some of the challenges of existing ANSI 12.15 (and draft ANSI 12.41) to measure sound power levels of electric (and pneumatic) powered hand tools.

  2. Sound power and vibration levels for two different piano soundboards

    Science.gov (United States)

    Squicciarini, Giacomo; Valiente, Pablo Miranda; Thompson, David J.

    2016-09-01

    This paper compares the sound power and vibration levels for two different soundboards for upright pianos. One of them is made of laminated spruce and the other of solid spruce (tone-wood). These differ also in the number of ribs and manufacturing procedure. The methodology used is defined in two major steps: (i) acoustic power due to a unit force is obtained reciprocally by measuring the acceleration response of the piano soundboards when excited by acoustic waves in reverberant field; (ii) impact tests are adopted to measure driving point and spatially-averaged mean-square transfer mobility. The results show that, in the midhigh frequency range, the soundboard made of solid spruce has a greater vibrational and acoustic response than the laminated soundboard. The effect of string tension is also addressed, showing that is only relevant at low frequencies.

  3. Effects of body mass index and adenotonsillar size on snoring sound intensity levels at highest power.

    Science.gov (United States)

    Seren, Erdal; San, Turhan; Cingi, Cemal; Muluk, Nuray Bayar; Durukan, Kübra

    2014-01-01

    Snoring during sleep is a major clinical symptom of adenoid and tonsil hypertrophy in paediatric patients. The aim of this study was to determine the effects of adenoid and tonsil size on snoring sound frequency and intensity in children. Twenty-seven patients with adenotonsillar hypertrophy were included the study. Adenoid size was graded from 1+ to 4+ by rigid endoscopy. Patients were staged (I-III) according to body mass index (BMI) and tonsil and adenoid size. Snoring was recorded and analysed. The analysis focused on the highest power frequency (Fmax) and snoring sound intensity levels (SSILs). SSIL and Fmax values for Stage III were significantly higher than those for Stages I and II. BMI for Stage III was higher than for Stages I and II, and that for Stage II was higher than for Stage I. The BMI, SSIL, and Fmax values increased at each stage and tonsil/adenoid grade. SSIL seems to be related to Adenoid and Tonsils size and BMI. As stage increased, both Fmax and SSILs increased proportionally. Also, Fmax values shifted to higher frequencies. Physicians and parents should be aware of snoring, and be informed that a higher frequency and intensity may be related to obesity and/or adenotonsillar hypertrophy. Snoring analysis may be a useful tool for detecting cases of Adenoid and Tonsils hypertrophy and/or upper airway obstruction during sleep. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. Technique for estimating the sound power level radiated by pneumatic rock drills and the evaluation of a CSIR prototype rock drill with engineering noise controls

    CSIR Research Space (South Africa)

    Kovalchik, PG

    2009-05-01

    Full Text Available This report describes the procedure for the measurement and reporting of noise from portable pneumatic tools such as jackleg drills. The technique used in this research allows for the determination of the source A-weighted sound power levels...

  5. Sound absorption of porous metals at high sound pressure levels.

    Science.gov (United States)

    Wang, Xiaolin; Peng, Feng; Chang, Baojun

    2009-08-01

    This paper is a study about sound absorption properties of porous metals at high sound pressure levels. A method of deriving the nonlinear static flow resistance for highly porous fibrous metals is proposed by solving Oseen's equation to take account of the inertia effect, validated by experiments of airflow measurement. In order to predict nonlinear sound absorbing performance of a finite thickness porous metal layer, a numerical method is employed, verified by sound absorption measurement in an impedance tube. Accordingly, the effects of the nonlinear coefficient on the porous metal sound absorption are investigated.

  6. Offshore dredger sounds: Source levels, sound maps, and risk assessment

    NARCIS (Netherlands)

    Jong, C.A.F. de; Ainslie, M.A.; Heinis, F.; Janmaat, J.

    2016-01-01

    The underwater sound produced during construction of the Port of Rotterdam harbor extension (Maasvlakte 2) was measured, with emphasis on the contribution of the trailing suction hopper dredgers during their various activities: dredging, transport, and discharge of sediment. Measured source levels

  7. Sound Levels in East Texas Schools.

    Science.gov (United States)

    Turner, Aaron Lynn

    A survey of sound levels was taken in several Texas schools to determine the amount of noise and sound present by size of class, type of activity, location of building, and the presence of air conditioning and large amounts of glass. The data indicate that class size and relative amounts of glass have no significant bearing on the production of…

  8. Level dominance in sound source identification.

    Science.gov (United States)

    Lutfi, Robert A; Liu, Ching-Ju; Stoelinga, Christophe

    2008-12-01

    Impact sounds were synthesized according to standard textbook equations given for the motion of simply supported, metal plates. In a two-interval, forced-choice procedure, highly practiced listeners identified from these sounds a predefined class of target plates based on their particular material and geometric properties. The effects of two factors on identification were examined: the relative level of partials comprising the sounds and the relative amount of information (given as the difference in d(')) each partial provided for identification. In different conditions one factor was fixed while the other either increased or decreased with frequency. The effect on listener identification in each case was determined from a logistic discriminant analysis of trial-by-trial responses, yielding a vector of listener decision weights on the frequency and decay of individual partials. The weights increased proportionally with relative level, but were largely uninfluenced by relative information content--a result exactly opposite to that expected from a maximum-likelihood observer. The dominant effect of relative level was replicated for other sound sources (clamped bars and stretched membranes) and was not diminished by randomizing the relative level of partials across trials. The results are taken to underscore the importance of relative level in the identification of rudimentary sound sources.

  9. Wind turbine sound pressure level calculations at dwellings.

    Science.gov (United States)

    Keith, Stephen E; Feder, Katya; Voicescu, Sonia A; Soukhovtsev, Victor; Denning, Allison; Tsang, Jason; Broner, Norm; Leroux, Tony; Richarz, Werner; van den Berg, Frits

    2016-03-01

    This paper provides calculations of outdoor sound pressure levels (SPLs) at dwellings for 10 wind turbine models, to support Health Canada's Community Noise and Health Study. Manufacturer supplied and measured wind turbine sound power levels were used to calculate outdoor SPL at 1238 dwellings using ISO [(1996). ISO 9613-2-Acoustics] and a Swedish noise propagation method. Both methods yielded statistically equivalent results. The A- and C-weighted results were highly correlated over the 1238 dwellings (Pearson's linear correlation coefficient r > 0.8). Calculated wind turbine SPLs were compared to ambient SPLs from other sources, estimated using guidance documents from the United States and Alberta, Canada.

  10. Research on the sound absorption characteristics of porous metal materials at high sound pressure levels

    Directory of Open Access Journals (Sweden)

    Xiaopeng Wang

    2015-05-01

    Full Text Available Porous metal materials are widely used in noise control with high sound pressure applications such as aircraft engine liners and combustion chambers for rocket engines due to their excellent performance of sound absorption characteristics and distinguished advantages in heat resistance, lightness, and stiffness. Understanding the effect of sound pressure on the acoustic properties of these materials is crucial when attempting to predict silencer performance. In this article, we experimentally investigate the sound absorption characteristics of porous metal materials at high sound pressure level. The effects of material parameters on the sound absorption characteristics of porous metal materials under high sound pressure level are further explored experimentally. Measurements are carried out by using a standard impedance tube that has been modified to accommodate sound pressure level of up to 150 dB. The experimental results show that with the increase in sound pressure level, the effect of sound pressure level on the sound absorption characteristics yields different variation regularities in different frequencies. The sound absorption performance of porous metal materials increases with the increase in sound pressure level in low frequency, which is reasonably consistent with the theoretical results. Under high sound pressure level, the sound absorption characteristics are significantly dependent upon the material parameters such as the metal fiber diameter, the material porosity, and the material thickness. It could provide a reliable experimental validation for the applications of porous metal materials in the area of vibration and noise control at high sound pressure levels.

  11. Sound

    CERN Document Server

    2013-01-01

    Sound has the power to soothe, excite, warn, protect, and inform. Indeed, the transmission and reception of audio signals pervade our daily lives. Readers will examine the mechanics and properties of sound and provides an overview of the "interdisciplinary science called acoustics." Also covered are functions and diseases of the human ear.

  12. Measurement of incident sound power using near field acoustic holography

    DEFF Research Database (Denmark)

    Jacobsen, Finn; Tiana Roig, Elisabet

    2009-01-01

    ; and it has always been regarded as impossible to measure the sound power that is incident on a wall directly. This paper examines a new method of determining this quantity from sound pressure measurements at positions on the wall using ‘statistically optimised near field acoustic holography’ (SONAH...

  13. Speed of sound in biodiesel produced by low power ultrasound

    Science.gov (United States)

    Oliveira, P. A.; Silva, R. M. B.; Morais, G. C.; Alvarenga, A. V.; Costa-Felix, R. P. B.

    2018-03-01

    The quality control of the biodiesel produced is an important issue to be addressed for every manufacturer or retailer. The speed of sound is a property that has an influence on the quality of the produced fuel. This work presents the evaluation about the speed of sound in biodiesel produced with the aid of low power ultrasound in the frequencies of 1 MHz and 3 MHz. The speed of sound was measured by pulse-echo technique. The ultrasonic frequency used during reaction affects the speed of sound in biodiesel. The larger expanded uncertainty for adjusted curve was 4.9 m.s-1.

  14. Can road traffic mask sound from wind turbines? Response to wind turbine sound at different levels of road traffic sound

    International Nuclear Information System (INIS)

    Pedersen, Eja; Berg, Frits van den; Bakker, Roel; Bouma, Jelte

    2010-01-01

    Wind turbines are favoured in the switch-over to renewable energy. Suitable sites for further developments could be difficult to find as the sound emitted from the rotor blades calls for a sufficient distance to residents to avoid negative effects. The aim of this study was to explore if road traffic sound could mask wind turbine sound or, in contrast, increases annoyance due to wind turbine noise. Annoyance of road traffic and wind turbine noise was measured in the WINDFARMperception survey in the Netherlands in 2007 (n=725) and related to calculated levels of sound. The presence of road traffic sound did not in general decrease annoyance with wind turbine noise, except when levels of wind turbine sound were moderate (35-40 dB(A) Lden) and road traffic sound level exceeded that level with at least 20 dB(A). Annoyance with both noises was intercorrelated but this correlation was probably due to the influence of individual factors. Furthermore, visibility and attitude towards wind turbines were significantly related to noise annoyance of modern wind turbines. The results can be used for the selection of suitable sites, possibly favouring already noise exposed areas if wind turbine sound levels are sufficiently low.

  15. Sound level measurements using smartphone "apps": Useful or inaccurate?

    Directory of Open Access Journals (Sweden)

    Daniel R Nast

    2014-01-01

    Full Text Available Many recreational activities are accompanied by loud concurrent sounds and decisions regarding the hearing hazards associated with these activities depend on accurate sound measurements. Sound level meters (SLMs are designed for this purpose, but these are technical instruments that are not typically available in recreational settings and require training to use properly. Mobile technology has made such sound level measurements more feasible for even inexperienced users. Here, we assessed the accuracy of sound level measurements made using five mobile phone applications or "apps" on an Apple iPhone 4S, one of the most widely used mobile phones. Accuracy was assessed by comparing application-based measurements to measurements made using a calibrated SLM. Whereas most apps erred by reporting higher sound levels, one application measured levels within 5 dB of a calibrated SLM across all frequencies tested.

  16. Sound power flux measurements in strongly exited ducts with flow

    Science.gov (United States)

    Holland, Keith R.; Davies, Peter O. A. L.; van der Walt, Danie C.

    2002-12-01

    This contribution describes new robust procedures for the measurement of sound power flux at appropriate axial positions along a duct with flow, using pairs of flush wall mounted microphones, or pressure transducers. The technology includes the application of selective averaging, order tracking, and optimized sampling rate methods to identify the small fraction of the total fluctuating wave energy that is being propagated along the flow path in a reverberent, or highly reactive duct system. Such measurements can also be used to quantify the local acoustic characteristics that govern the generation, transfer, and propagation of wave energy in the system. Illustrative examples include the determination of the acoustic characteristics of individual silencing elements installed in IC engine intakes and exhausts both on the flow bench and during controlled acceleration or run down on a test bed, where the wave component spectral levels approached 170 dB.

  17. Decoding sound level in the marmoset primary auditory cortex.

    Science.gov (United States)

    Sun, Wensheng; Marongelli, Ellisha N; Watkins, Paul V; Barbour, Dennis L

    2017-10-01

    Neurons that respond favorably to a particular sound level have been observed throughout the central auditory system, becoming steadily more common at higher processing areas. One theory about the role of these level-tuned or nonmonotonic neurons is the level-invariant encoding of sounds. To investigate this theory, we simulated various subpopulations of neurons by drawing from real primary auditory cortex (A1) neuron responses and surveyed their performance in forming different sound level representations. Pure nonmonotonic subpopulations did not provide the best level-invariant decoding; instead, mixtures of monotonic and nonmonotonic neurons provided the most accurate decoding. For level-fidelity decoding, the inclusion of nonmonotonic neurons slightly improved or did not change decoding accuracy until they constituted a high proportion. These results indicate that nonmonotonic neurons fill an encoding role complementary to, rather than alternate to, monotonic neurons. NEW & NOTEWORTHY Neurons with nonmonotonic rate-level functions are unique to the central auditory system. These level-tuned neurons have been proposed to account for invariant sound perception across sound levels. Through systematic simulations based on real neuron responses, this study shows that neuron populations perform sound encoding optimally when containing both monotonic and nonmonotonic neurons. The results indicate that instead of working independently, nonmonotonic neurons complement the function of monotonic neurons in different sound-encoding contexts. Copyright © 2017 the American Physiological Society.

  18. Analysis of the sources of error in the determination of sound power based on sound intensity measurements

    DEFF Research Database (Denmark)

    Santillan, Arturo Orozco; Jacobsen, Finn

    2010-01-01

    Sound intensity measurements make it possible to determine the sound power of a source in situ, even in the presence of other sources. However, the very fact that intensity-based sound power measurements can take place under widely different conditions makes it extremely difficult to evaluate...... the resulting measurement uncertainty. The purpose of this paper is to analyze the effect of the most common sources of error in sound power determination based on sound intensity measurements. In particular the influence of the scanning procedure used in approximating the surface integral of the intensity...

  19. Acoustic analysis of overnight consecutive snoring sounds by sound pressure levels.

    Science.gov (United States)

    Peng, Hao; Xu, Huijie; Gao, Zhan; Huang, Weining; He, Yuxia

    2015-08-01

    The sound pressure level (SPL) parameters, especially the A-weighted equivalent sound level (LAeq) and accumulative percentile sound level 10 (L10), were significantly different between simple snoring (SS) and obstructive sleep apnea-hypopnea syndrome (OSAHS). The apnea-hypopnea index (AHI) was the most significant factor to affect the SPLs of snoring sounds. LAeq and L10 were valuable acoustic characters of snoring which could reflect the severity of sleep disordered breathing in clinic. Due to the limitation of acoustic analysis of single snoring sound for snorers, this study analyzed characteristics of consecutive snoring sounds overnight by the SPLs in patients of SS and OSAHS. Ninety-four patients who underwent simultaneous SPL recording and polysomnography (PSG) were included in this study. Parameters of SPL such as LAeq, peak sound level (Lpeak), L10, L50, and L90 were analyzed. The correlation between these parameters and PSG results was also analyzed. The LAeq and L10 in OSAHS patients were significantly different from patients with SS. The body mass index (BMI) was positively correlated to LAeq and L10. Among various factors of PSG data and demographic factors, the SPLs were mostly affected by the AHI and the lowest oxygen saturation (LSaO2).

  20. Opponent Coding of Sound Location (Azimuth) in Planum Temporale is Robust to Sound-Level Variations.

    Science.gov (United States)

    Derey, Kiki; Valente, Giancarlo; de Gelder, Beatrice; Formisano, Elia

    2016-01-01

    Coding of sound location in auditory cortex (AC) is only partially understood. Recent electrophysiological research suggests that neurons in mammalian auditory cortex are characterized by broad spatial tuning and a preference for the contralateral hemifield, that is, a nonuniform sampling of sound azimuth. Additionally, spatial selectivity decreases with increasing sound intensity. To accommodate these findings, it has been proposed that sound location is encoded by the integrated activity of neuronal populations with opposite hemifield tuning ("opponent channel model"). In this study, we investigated the validity of such a model in human AC with functional magnetic resonance imaging (fMRI) and a phase-encoding paradigm employing binaural stimuli recorded individually for each participant. In all subjects, we observed preferential fMRI responses to contralateral azimuth positions. Additionally, in most AC locations, spatial tuning was broad and not level invariant. We derived an opponent channel model of the fMRI responses by subtracting the activity of contralaterally tuned regions in bilateral planum temporale. This resulted in accurate decoding of sound azimuth location, which was unaffected by changes in sound level. Our data thus support opponent channel coding as a neural mechanism for representing acoustic azimuth in human AC. © The Author 2015. Published by Oxford University Press.

  1. Sound Levels and Risk Perceptions of Music Students During Classes.

    Science.gov (United States)

    Rodrigues, Matilde A; Amorim, Marta; Silva, Manuela V; Neves, Paula; Sousa, Aida; Inácio, Octávio

    2015-01-01

    It is well recognized that professional musicians are at risk of hearing damage due to the exposure to high sound pressure levels during music playing. However, it is important to recognize that the musicians' exposure may start early in the course of their training as students in the classroom and at home. Studies regarding sound exposure of music students and their hearing disorders are scarce and do not take into account important influencing variables. Therefore, this study aimed to describe sound level exposures of music students at different music styles, classes, and according to the instrument played. Further, this investigation attempted to analyze the perceptions of students in relation to exposure to loud music and consequent health risks, as well as to characterize preventive behaviors. The results showed that music students are exposed to high sound levels in the course of their academic activity. This exposure is potentiated by practice outside the school and other external activities. Differences were found between music style, instruments, and classes. Tinnitus, hyperacusis, diplacusis, and sound distortion were reported by the students. However, students were not entirely aware of the health risks related to exposure to high sound pressure levels. These findings reflect the importance of starting intervention in relation to noise risk reduction at an early stage, when musicians are commencing their activity as students.

  2. Sound pressure level tools design used in occupational health by means of Labview software

    Directory of Open Access Journals (Sweden)

    Farhad Forouharmajd

    2015-01-01

    Conclusion: LabVIEW programming capabilities in the field of sound can be referred to the measurement of sound, frequency analysis, and sound control that actually the software acts like a sound level meter and sound analyzer. According to the mentioned features, we can use this software to analyze and process sound and vibration as a monitoring system.

  3. Behavioral response of manatees to variations in environmental sound levels

    Science.gov (United States)

    Miksis-Olds, Jennifer L.; Wagner, Tyler

    2011-01-01

    Florida manatees (Trichechus manatus latirostris) inhabit coastal regions because they feed on the aquatic vegetation that grows in shallow waters, which are the same areas where human activities are greatest. Noise produced from anthropogenic and natural sources has the potential to affect these animals by eliciting responses ranging from mild behavioral changes to extreme aversion. Sound levels were calculated from recordings made throughout behavioral observation periods. An information theoretic approach was used to investigate the relationship between behavior patterns and sound level. Results indicated that elevated sound levels affect manatee activity and are a function of behavioral state. The proportion of time manatees spent feeding and milling changed in response to sound level. When ambient sound levels were highest, more time was spent in the directed, goal-oriented behavior of feeding, whereas less time was spent engaged in undirected behavior such as milling. This work illustrates how shifts in activity of individual manatees may be useful parameters for identifying impacts of noise on manatees and might inform population level effects.

  4. The Relationship Between Sound Levels in the Postanesthesia Care Unit and use of a Analgesics

    National Research Council Canada - National Science Library

    Burry, Marjorie

    2000-01-01

    ...) and the use of analgesics was conducted. Previous studies indicated sound levels in the PACU exceeded federal recommendations, that more analgesics were used during periods of higher sound, and that many of the sounds in higher levels...

  5. A study investigating sound sources and noise levels in neonatal ...

    African Journals Online (AJOL)

    readings were taken with a calibrated Quest Technologies 210 Sound. Level Meter and measured in dB. At each site, the layout of the NICU was recorded by a sketch documenting the location of the nurses' station and the position of the incubators (Figs 1 - 3). The nurse-to-patient ratio, occupancy of incubators and loudest ...

  6. A study investigating sound sources and noise levels in neonatal ...

    African Journals Online (AJOL)

    This study aimed to identify noise sources in three NICUs in Johannesburg, South Africa, and to determine the sound levels to which neonates in incubators are exposed at various positions in the NICU. These findings were then compared with the standards recommended by the American Academy of Pediatrics (AAP).

  7. Effects of interaural level differences on the externalization of sound

    DEFF Research Database (Denmark)

    Catic, Jasmina; Santurette, Sébastien; Dau, Torsten

    2012-01-01

    differences (ILDs) and interaural time differences (ITDs). In rooms, the sound reaching the two ears is further modified by reverberant energy, which leads to increased fluctuations in short-term ILDs and ITDs. In the present study, the effect of ILD fluctuations on the externalization of sound......Distant sound sources in our environment are perceived as externalized and are thus properly localized in both direction and distance. This is due to the acoustic filtering by the head, torso, and external ears, which provides frequency-dependent shaping of binaural cues such as interaural level...... fluctuations in the ILDs were compressed, while the ITDs were preserved. This manipulation reduced the perceived degree of externalization mainly for broadband and highpass filtered speech. In the case of lowpass filtered speech, the compression of ILD fluctuations did not affect externalization. Overall...

  8. Blast noise classification with common sound level meter metrics.

    Science.gov (United States)

    Cvengros, Robert M; Valente, Dan; Nykaza, Edward T; Vipperman, Jeffrey S

    2012-08-01

    A common set of signal features measurable by a basic sound level meter are analyzed, and the quality of information carried in subsets of these features are examined for their ability to discriminate military blast and non-blast sounds. The analysis is based on over 120 000 human classified signals compiled from seven different datasets. The study implements linear and Gaussian radial basis function (RBF) support vector machines (SVM) to classify blast sounds. Using the orthogonal centroid dimension reduction technique, intuition is developed about the distribution of blast and non-blast feature vectors in high dimensional space. Recursive feature elimination (SVM-RFE) is then used to eliminate features containing redundant information and rank features according to their ability to separate blasts from non-blasts. Finally, the accuracy of the linear and RBF SVM classifiers is listed for each of the experiments in the dataset, and the weights are given for the linear SVM classifier.

  9. SOUND LABOR RELATIONS AT ENTERPRISE LEVEL IN THAILAND

    Directory of Open Access Journals (Sweden)

    Vichai Thosuwonchinda

    2016-07-01

    Full Text Available The objective of this research was to study the pattern of sound labor relations in Thailand in order to reduce conflicts between employers and workers and create cooperation. The research was based on a qualitative approach, using in-depth interview with 10 stakeholder groups of Thai industrial relations system. They were employees of non unionized companies at the shop floor level, employees of non unionized companies at the supervisor level, trade union leaders at the company level, trade union leaders at the national level, employers of non-unionized companies, employers’ organization leaders, and human resource managers, members of tripartite bodies, government officials and labor academics. The findings were presented in a model identifying 5 characteristics that enhance sound relations in Thailand, i.e. recognition between employer and workers, good communication, trust, data revealing and workers’ participation. It was suggested that all parties, employers, workers and the government should take part in the promotion of sound labor relations. The employer have to acknowledge labor union with a positive attitude, have good communication with workers , create trust with workers, disclose information, create culture of mutual benefits as well as accept sincerely the system that include workers’ participation. Workers need a strong labor union, good and sincere representatives for clear communication, trust, mutual benefits and seek conflict solutions with employer by win-win strategy. The government has a supporting role in adjusting the existing laws in the appropriate way, by creating policy for sound labor relations, and putting the idea of sound labor relations into practice.

  10. Sound Power Estimation by Laser Doppler Vibration Measurement Techniques

    Directory of Open Access Journals (Sweden)

    G.M. Revel

    1998-01-01

    Full Text Available The aim of this paper is to propose simple and quick methods for the determination of the sound power emitted by a vibrating surface, by using non-contact vibration measurement techniques. In order to calculate the acoustic power by vibration data processing, two different approaches are presented. The first is based on the method proposed in the Standard ISO/TR 7849, while the second is based on the superposition theorem. A laser-Doppler scanning vibrometer has been employed for vibration measurements. Laser techniques open up new possibilities in this field because of their high spatial resolution and their non-intrusivity. The technique has been applied here to estimate the acoustic power emitted by a loudspeaker diaphragm. Results have been compared with those from a commercial Boundary Element Method (BEM software and experimentally validated by acoustic intensity measurements. Predicted and experimental results seem to be in agreement (differences lower than 1 dB thus showing that the proposed techniques can be employed as rapid solutions for many practical and industrial applications. Uncertainty sources are addressed and their effect is discussed.

  11. Weak Anderson localisation in reverberation rooms and its effect on the uncertainty of sound power measurements

    DEFF Research Database (Denmark)

    Jacobsen, Finn

    2011-01-01

    The effect known as ‘weak Anderson localisation’, ‘coherent backscattering’ or ‘enhanced backscattering’ is a physical phenomenon that occurs in random systems, e.g., disordered media and linear wave systems, including reverberation rooms: the mean square response is increased at the drive point....... In a reverberation room this means that one can expect an increase of the reverberant sound field at the position of the source that generates the sound field. This affects the sound power output of the source and is therefore of practical concern. However, because of the stronger direct sound field at the source...... for the uncertainty of sound power measurements....

  12. Sound

    CERN Document Server

    Robertson, William C

    2003-01-01

    Muddled about what makes music? Stuck on the study of harmonics? Dumbfounded by how sound gets around? Now you no longer have to struggle to teach concepts you really don t grasp yourself. Sound takes an intentionally light touch to help out all those adults science teachers, parents wanting to help with homework, home-schoolers seeking necessary scientific background to teach middle school physics with confidence. The book introduces sound waves and uses that model to explain sound-related occurrences. Starting with the basics of what causes sound and how it travels, you'll learn how musical instruments work, how sound waves add and subtract, how the human ear works, and even why you can sound like a Munchkin when you inhale helium. Sound is the fourth book in the award-winning Stop Faking It! Series, published by NSTA Press. Like the other popular volumes, it is written by irreverent educator Bill Robertson, who offers this Sound recommendation: One of the coolest activities is whacking a spinning metal rod...

  13. Transformer sound level caused by core magnetostriction and winding stress displacement variation

    Directory of Open Access Journals (Sweden)

    Chang-Hung Hsu

    2017-05-01

    Full Text Available Magnetostriction caused by the exciting variation of the magnetic core and the current conducted by the winding wired to the core has a significant result impact on a power transformer. This paper presents the sound of a factory transformer before on-site delivery for no-load tests. This paper also discusses the winding characteristics from the transformer full-load tests. The simulation and the measurement for several transformers with capacities ranging from 15 to 60 MVA and high voltage 132kV to low voltage 33 kV are performed. This study compares the sound levels for transformers by no-load test (core/magnetostriction and full-load test (winding/displacement ε. The difference between the simulated and the measured sound levels is about 3dB. The results show that the sound level depends on several parameters, including winding displacement, capacity, mass of the core and windings. Comparative results of magnetic induction of cores and the electromagnetic force of windings for no-load and full-load conditions are examined.

  14. The low-frequency sound power measuring technique for an underwater source in a non-anechoic tank

    Science.gov (United States)

    Zhang, Yi-Ming; Tang, Rui; Li, Qi; Shang, Da-Jing

    2018-03-01

    In order to determine the radiated sound power of an underwater source below the Schroeder cut-off frequency in a non-anechoic tank, a low-frequency extension measuring technique is proposed. This technique is based on a unique relationship between the transmission characteristics of the enclosed field and those of the free field, which can be obtained as a correction term based on previous measurements of a known simple source. The radiated sound power of an unknown underwater source in the free field can thereby be obtained accurately from measurements in a non-anechoic tank. To verify the validity of the proposed technique, a mathematical model of the enclosed field is established using normal-mode theory, and the relationship between the transmission characteristics of the enclosed and free fields is obtained. The radiated sound power of an underwater transducer source is tested in a glass tank using the proposed low-frequency extension measuring technique. Compared with the free field, the radiated sound power level of the narrowband spectrum deviation is found to be less than 3 dB, and the 1/3 octave spectrum deviation is found to be less than 1 dB. The proposed testing technique can be used not only to extend the low-frequency applications of non-anechoic tanks, but also for measurement of radiated sound power from complicated sources in non-anechoic tanks.

  15. Active control of radiated sound power from a baffled, rectangular panel

    DEFF Research Database (Denmark)

    Mørkholt, Jakob

    1996-01-01

    with an array of eleven microphones in front of the panel, is very close to minimising the actual radiated sound power. Practical experiments where such an array estimate has been minimised using the filtered X LMS algorithm have shown that substantial reductions of radiated sound power can be obtained over......Active control of radiated sound power from a rectangular baffled panel by minimisation of an accurate power estimate, using piezoceramic actuators, has been investigated. Computer simulations have shown that minimising a power estimate obtained by discretised integration of the far field intensity...... a broad frequency range using few piezoceramic actuators, provided that an accurate estimate of the sound power is available for minimisation....

  16. Research on the sound absorption characteristics of porous metal materials at high sound pressure levels

    OpenAIRE

    Xiaopeng Wang; Yinggang Li; Tianning Chen; Zhiping Ying

    2015-01-01

    Porous metal materials are widely used in noise control with high sound pressure applications such as aircraft engine liners and combustion chambers for rocket engines due to their excellent performance of sound absorption characteristics and distinguished advantages in heat resistance, lightness, and stiffness. Understanding the effect of sound pressure on the acoustic properties of these materials is crucial when attempting to predict silencer performance. In this article, we experimentally...

  17. Sound

    CERN Document Server

    Rivera, Andrea

    2017-01-01

    Sound is all around us. Learn how it is used in art, technology, and engineering. Five easy-to-read chapters explain the science behind sound, as well as its real-world applications. Vibrant, full-color photos, bolded glossary words, and a key stats section let readers zoom in even deeper. Aligned to Common Core Standards and correlated to state standards. Abdo Zoom is a division of ABDO.

  18. Sound power spectrum and wave drag of a propeller in flight

    Science.gov (United States)

    Hanson, D. B.

    1989-01-01

    Theory is presented for the sound power and sound power spectrum of a single rotation propeller in forward flight. Calculations are based on the linear wave equation with sources distributed over helicoidal surfaces to represent effects of blade thickness and steady loading. Sound power is distributed continuously over frequecy, as would be expected from Doppler effects, rather than in discrete harmonics. The theory is applied to study effects of sweep and Mach number in propfans. An acoustic efficiency is defined as the ratio of radiated sound power to shaft input power. This value is the linear estimate of the effect of wave drag due to the supersonic blade section speeds. It is shown that the acoustic efficiency is somewhat less than 1 percent for a well designed propfan.

  19. Nuclear power: levels of safety

    International Nuclear Information System (INIS)

    Lidsky, L.M.

    1988-01-01

    The rise and fall of the nuclear power industry in the United States is a well-documented story with enough socio-technological conflict to fill dozens of scholarly, and not so scholarly, books. Whatever the reasons for the situation we are now in, and no matter how we apportion the blame, the ultimate choice of whether to use nuclear power in this country is made by the utilities and by the public. Their choices are, finally, based on some form of risk-benefit analysis. Such analysis is done in well-documented and apparently logical form by the utilities and in a rather more inchoate but not necessarily less accurate form by the public. Nuclear power has failed in the United States because both the real and perceived risks outweigh the potential benefits. The national decision not to rely upon nuclear power in its present form is not an irrational one. A wide ranging public balancing of risk and benefit requires a classification of risk which is clear and believable for the public to be able to assess the risks associated with given technological structures. The qualitative four-level safety ladder provides such a framework. Nuclear reactors have been designed which fit clearly and demonstrably into each of the possible qualitative safety levels. Surprisingly, it appears that safer may also mean cheaper. The intellectual and technical prerequisites are in hand for an important national decision. Deployment of a qualitatively different second generation of nuclear reactors can have important benefits for the United States. Surprisingly, it may well be the nuclear establishment itself, with enormous investments of money and pride in the existing nuclear systems, that rejects second generation reactors. It may be that we will not have a second generation of reactors until the first generation of nuclear engineers and nuclear power advocates has retired

  20. An overview of the sources of error in sound power determination using the intensity technique

    DEFF Research Database (Denmark)

    Jacobsen, Finn

    1997-01-01

    An overview of the most important sources of error in sound power determination with the sound intensity technique is presented. It is concluded that the method is convenient, accurate and reliable provided that a few simple rules are observed. (C) 1997 Elsevier Science Ltd....

  1. Can road traffic mask sound from wind turbines? Response to wind turbine sound at different levels of road traffic sound

    NARCIS (Netherlands)

    Pedersen, Eja; van den Berg, Frits; Bakker, Roel; Bouma, Jelte

    Wind turbines are favoured in the switch-over to renewable energy. Suitable sites for further developments could be difficult to find as the sound emitted from the rotor blades calls for a sufficient distance to residents to avoid negative effects. The aim of this study was to explore if road

  2. Biomass power production in Amazonia: Environmentally sound, economically productive

    Energy Technology Data Exchange (ETDEWEB)

    Waddle, D.B. [National Rural Electric Cooperative Association, Washington, DC (United States); Hollomon, J.B. [Winrock International Institute for Agricultural Development, Arlington, VA (United States)

    1993-12-31

    With the support of the US Agency for International Development, the National Rural Electric Cooperative Association (NRECA) is assisting their utility counterparts in Bolivia to improve electric service in the country`s rural population. In remote areas, the cost of extending transmission lines to small communities is prohibitive, and diesel generators represent an expensive alternative, especially for baseload power. This has led to serious consideration of electric generating systems using locally available renewable resources, including biomass, hydro, wind, and solar energy. A project has recently been initiated in Riberalta, in the Amazonian region of Bolivia, to convert waste Brazil nut shells and sawmill residues to electricity. Working in tandem with diesel generators, the biomass-fired plant will produce base-load power in an integrated system that will be able to provide reliable and affordable electricity to the city. The project will allow the local rural electric cooperative to lower the price of electricity by nearly forty percent, enable the local Brazil nut industry to increase its level of mechanization, and reduce the environmental impacts of dumping waste shells around the city and in an adjacent river. The project is representative of others that will be funded in the future by NRECA/AID.

  3. Measurement of sound power and absorption in reverberation chambers using energy density.

    Science.gov (United States)

    Nutter, David B; Leishman, Timothy W; Sommerfeldt, Scott D; Blotter, Jonathan D

    2007-05-01

    Reverberation chamber measurements typically rely upon spatially averaged squared pressure for the calculation of sound absorption, sound power, and other acoustic values. While a reverberation chamber can provide an approximately diffuse sound field, variations in sound pressure consistently produce uncertainty in measurement results. This paper explores the benefits of using total energy density or squared particle velocity magnitude (kinetic energy density) instead of squared pressure (potential energy density) for sound absorption and sound power measurements. The approaches are based on methods outlined in current ISO standards. The standards require a sufficient number of source-receiver locations to obtain suitable measurement results. The total and kinetic energy densities exhibit greater spatial uniformity at most frequencies than potential energy density, thus requiring fewer source-receiver positions to produce effective results. Because the total energy density is typically the most uniform of the three quantities at low frequencies, its use could also impact the usable low-frequency ranges of reverberation chambers. In order to employ total and kinetic energy densities for sound absorption measurements, relevant energy-based impulse responses were developed as part of the work for the assessment of sound field decays.

  4. Water-Level Analysis for Cumberland Sound, Georgia

    National Research Council Canada - National Science Library

    Kraus, Nicholas

    1997-01-01

    Cumberland Sound, Georgia, is a large and complex estuary covering an area of approximately 240 square miles, which is connected to the Atlantic Ocean through a dredged inlet channel called St Marys Entrance. St...

  5. Exterior sound level measurements of snowcoaches at Yellowstone National Park

    Science.gov (United States)

    2010-04-01

    Sounds associated with oversnow vehicles, such as snowmobiles and snowcoaches, are an important management concern at Yellowstone and Grand Teton National Parks. The John A. Volpe National Transportation Systems Centers Environmental Measurement a...

  6. Effects of acupuncture on the heart rate variability, cortisol levels and behavioural response induced by thunder sound in beagles.

    Science.gov (United States)

    Maccariello, Carolina Elisabetta Martins; Franzini de Souza, Carla Caroline; Morena, Laura; Dias, Daniel Penteado Martins; Medeiros, Magda Alves de

    2018-03-15

    Sound stimuli such as fireworks, firearms, and claps of thunder have been used as a stress reactivity model for dogs. Acupuncture has been widely used to treat and prevent physiological and behavioural disorders induced by stress. Our study aims to evaluate the effects of acupuncture on cardiac autonomic modulation (heart rate variability - HRV), behavioural (reactivity) and endocrine (cortisol levels) responses in dogs exposed to sounds of thunder. Twenty-four laboratory beagles (12 males and 12 females, 1-6years old) with no history of phobia to thunder were subjected to a sound stimulus that consisted of a standardized recording of thunder over a 150s period with a maximum intensity of 103-104dB. Before the sound, the dogs underwent a 20-minute session of needle insertion at acupuncture points Yintang, GV20, HT7, PC6 and ST36 (ACUP), in non-points (NP) or left undisturbed (CTL). Cardiac intervals were recorded using a frequency meter (RS 800cx, Polar, Kempele, Finland) to evaluate the HRV, and the data were later analysed using CardioSeries v2.4.1 software. Acupuncture (ACUP) changed the sympathovagal balance with a shift towards parasympathetic modulation, reducing the prompt sound-induced increase in LF/HF (low frequency/high frequency) ratio and in the power of the LF band of the cardiac interval spectrum, and decreased the power of the HF band of the cardiac interval spectrum (pthunder (when all behavioural parameters were considered together) and the behaviours hiding, restlessness, bolting and running around (when the parameters were analysed separately (p<0.05). There were no changes in cortisol levels due to the sound stimulus or acupuncture. Our results demonstrate that a session of acupuncture prior to sound stimulus can reduce cardiac autonomic and behavioural responses, without changing cortisol levels in beagles. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. L-type calcium channels refine the neural population code of sound level

    Science.gov (United States)

    Grimsley, Calum Alex; Green, David Brian

    2016-01-01

    The coding of sound level by ensembles of neurons improves the accuracy with which listeners identify how loud a sound is. In the auditory system, the rate at which neurons fire in response to changes in sound level is shaped by local networks. Voltage-gated conductances alter local output by regulating neuronal firing, but their role in modulating responses to sound level is unclear. We tested the effects of L-type calcium channels (CaL: CaV1.1–1.4) on sound-level coding in the central nucleus of the inferior colliculus (ICC) in the auditory midbrain. We characterized the contribution of CaL to the total calcium current in brain slices and then examined its effects on rate-level functions (RLFs) in vivo using single-unit recordings in awake mice. CaL is a high-threshold current and comprises ∼50% of the total calcium current in ICC neurons. In vivo, CaL activates at sound levels that evoke high firing rates. In RLFs that increase monotonically with sound level, CaL boosts spike rates at high sound levels and increases the maximum firing rate achieved. In different populations of RLFs that change nonmonotonically with sound level, CaL either suppresses or enhances firing at sound levels that evoke maximum firing. CaL multiplies the gain of monotonic RLFs with dynamic range and divides the gain of nonmonotonic RLFs with the width of the RLF. These results suggest that a single broad class of calcium channels activates enhancing and suppressing local circuits to regulate the sensitivity of neuronal populations to sound level. PMID:27605536

  8. A- and C-weighted sound levels as predictors of the annoyance caused by shooting sounds, for various façade attenuation types

    Science.gov (United States)

    Vos, Joos

    2003-01-01

    In a previous study on the annoyance caused by a great variety of shooting sounds [J. Acoust. Soc. Am. 109, 244-253 (2001)], it was shown that the annoyance, as rated indoors with the windows closed, could be adequately predicted from the outdoor A-weighted and C-weighted sound-exposure levels [ASEL (LAE) and CSEL (LCE)] of the impulse sounds. The explained variance in the mean ratings by (outdoor) ASEL was significantly increased by adding the product (LCE- LAE)(LAE) as a second variable. In the present study it was investigated to which extent the additional contribution of the second predictor is also relevant for façade attenuation types with lower and higher degrees of sound isolation than applied previously. Twenty subjects rated the indoor annoyance caused by 11 different impulse types produced by firearms ranging in caliber from 7.62 to 155 mm, at various levels and for five façade attenuation conditions. The effect of façade attenuation on the ratings was large and consistent. In all conditions, an optimal prediction of the annoyance was obtained with outdoor ASEL as the first, and (LCE- LAE)(LAE) as the second predictor. The benefit of the second predictor, expressed as the increase in the explained variance, ranged from 2.5 to 55 percent points, and strongly increased with the degree of façade attenuation. It was concluded that for the determination of the rating sound level, the acoustic parameters ASEL and CSEL are very powerful. In addition, the results showed that for the whole set of impulses included, the annoyance could also be predicted very well by the weighted sum of indoor ASEL and the product (LCE- LAE)(LAE).

  9. The power of musical sound and its implications for primary education in South Africa: An experiential discussion

    Directory of Open Access Journals (Sweden)

    Christina Auerbach

    2014-11-01

    Full Text Available In this article, the power of musical sound and its transformative effects on human beings are explored, as perceived since ancient times and discussed in recent literature. An evolving research project is then reviewed, with a group of primary school children from disadvantaged backgrounds with no prior formal musical training. In essence, the aim of the study in progress is to determine how musical sound can be used to facilitate mindfulness, develop wholeness and facilitate the holistic growth of young South African learners, especially those from deprived backgrounds. Initial findings suggest that when musical sound experiences are included in everyday education of young learners, there are moments of joy, spontaneity, a sense of unity and well-being. The listening capacity of the children in the group has refined and performance levels at school have improved.

  10. Sound and sound sources

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Wahlberg, Magnus

    2017-01-01

    There is no difference in principle between the infrasonic and ultrasonic sounds, which are inaudible to humans (or other animals) and the sounds that we can hear. In all cases, sound is a wave of pressure and particle oscillations propagating through an elastic medium, such as air. This chapter...... is about the physical laws that govern how animals produce sound signals and how physical principles determine the signals’ frequency content and sound level, the nature of the sound field (sound pressure versus particle vibrations) as well as directional properties of the emitted signal. Many...... of these properties are dictated by simple physical relationships between the size of the sound emitter and the wavelength of emitted sound. The wavelengths of the signals need to be sufficiently short in relation to the size of the emitter to allow for the efficient production of propagating sound pressure waves...

  11. How male sound pressure level influences phonotaxis in virgin female Jamaican field crickets (Gryllus assimilis

    Directory of Open Access Journals (Sweden)

    Karen Pacheco

    2014-06-01

    Full Text Available Understanding female mate preference is important for determining the strength and direction of sexual trait evolution. The sound pressure level (SPL acoustic signalers use is often an important predictor of mating success because higher sound pressure levels are detectable at greater distances. If females are more attracted to signals produced at higher sound pressure levels, then the potential fitness impacts of signalling at higher sound pressure levels should be elevated beyond what would be expected from detection distance alone. Here we manipulated the sound pressure level of cricket mate attraction signals to determine how female phonotaxis was influenced. We examined female phonotaxis using two common experimental methods: spherical treadmills and open arenas. Both methods showed similar results, with females exhibiting greatest phonotaxis towards loud sound pressure levels relative to the standard signal (69 vs. 60 dB SPL but showing reduced phonotaxis towards very loud sound pressure level signals relative to the standard (77 vs. 60 dB SPL. Reduced female phonotaxis towards supernormal stimuli may signify an acoustic startle response, an absence of other required sensory cues, or perceived increases in predation risk.

  12. Hearing Tests on Mobile Devices: Evaluation of the Reference Sound Level by Means of Biological Calibration.

    Science.gov (United States)

    Masalski, Marcin; Kipiński, Lech; Grysiński, Tomasz; Kręcicki, Tomasz

    2016-05-30

    Hearing tests carried out in home setting by means of mobile devices require previous calibration of the reference sound level. Mobile devices with bundled headphones create a possibility of applying the predefined level for a particular model as an alternative to calibrating each device separately. The objective of this study was to determine the reference sound level for sets composed of a mobile device and bundled headphones. Reference sound levels for Android-based mobile devices were determined using an open access mobile phone app by means of biological calibration, that is, in relation to the normal-hearing threshold. The examinations were conducted in 2 groups: an uncontrolled and a controlled one. In the uncontrolled group, the fully automated self-measurements were carried out in home conditions by 18- to 35-year-old subjects, without prior hearing problems, recruited online. Calibration was conducted as a preliminary step in preparation for further examination. In the controlled group, audiologist-assisted examinations were performed in a sound booth, on normal-hearing subjects verified through pure-tone audiometry, recruited offline from among the workers and patients of the clinic. In both the groups, the reference sound levels were determined on a subject's mobile device using the Bekesy audiometry. The reference sound levels were compared between the groups. Intramodel and intermodel analyses were carried out as well. In the uncontrolled group, 8988 calibrations were conducted on 8620 different devices representing 2040 models. In the controlled group, 158 calibrations (test and retest) were conducted on 79 devices representing 50 models. Result analysis was performed for 10 most frequently used models in both the groups. The difference in reference sound levels between uncontrolled and controlled groups was 1.50 dB (SD 4.42). The mean SD of the reference sound level determined for devices within the same model was 4.03 dB (95% CI 3

  13. Optimization of Natural Frequencies and Sound Power of Beams Using Functionally Graded Material

    Directory of Open Access Journals (Sweden)

    Nabeel T. Alshabatat

    2014-01-01

    Full Text Available This paper presents a design method to optimize the material distribution of functionally graded beams with respect to some vibration and acoustic properties. The change of the material distribution through the beam length alters the stiffness and the mass of the beam. This can be used to alter a specific beam natural frequency. It can also be used to reduce the sound power radiated from the vibrating beam. Two novel volume fraction laws are used to describe the material volume distributions through the length of the FGM beam. The proposed method couples the finite element method (for the modal and harmonic analysis, Lumped Parameter Model (for calculating the power of sound radiation, and an optimization technique based on Genetic Algorithm. As a demonstration of this technique, the optimization procedure is applied to maximize the fundamental frequency of FGM cantilever and clamped beams and to minimize the sound radiation from vibrating clamped FGM beam at a specific frequency.

  14. A Loudness Function for Analog and Digital Sound Systems based on Equal Loudness Level Contours

    DEFF Research Database (Denmark)

    Nielsen, Sofus Birkedal

    2016-01-01

    A new and better loudness compensation has been designed based on the differences between the Equal Loudness Level Contours (ELLC) in ISO 226:2003. Sound productions are normally being mixed at a high mixing level (ML) but often played at lower listening level (LL) which mean that the perceived...... solution is realized in a 16/32 bit fixed point DSP and could be implemented in any sound producing system....

  15. Sound power emitted by a pure-tone source in a reverberation room

    DEFF Research Database (Denmark)

    Jacobsen, Finn; Molares, Alfonso Rodriguez

    2009-01-01

    Energy considerations are of enormous practical importance in acoustics. In "energy acoustics," sources of noise are described in terms of the sound power they emit, the underlying assumption being that this property is independent of the particular environment where the sources are placed. Howev...

  16. Numerical and analytical solutions for sound propagation and absorption in porous media at high sound pressure levels.

    Science.gov (United States)

    Zhang, Bo; Chen, Tianning; Zhao, Yuyuan; Zhang, Weiyong; Zhu, Jian

    2012-09-01

    On the basis of the work of Wilson et al. [J. Acoust. Soc. Am. 84, 350-359 (1988)], a more exact numerical approach was constructed for predicting the nonlinear sound propagation and absorption properties of rigid porous media at high sound pressure levels. The numerical solution was validated by the experimental results for sintered fibrous porous steel samples and its predictions were compared with the numerical solution of Wilson et al. An approximate analytical solution was further put forward for the normalized surface acoustic admittance of rigid air-saturated porous materials with infinite thickness, based on the wave perturbation method developed by Lambert and McIntosh [J. Acoust. Soc. Am. 88, 1950-1959 (1990)]. Comparisons were made with the numerical results.

  17. Modulation of the sound press level by the treatment of polymer diaphragms through ion implantation method

    International Nuclear Information System (INIS)

    Yeo, Sunmog; Park, Jaewon; Lee, Hojae

    2010-01-01

    We present two different surface modification treatments, an ion implantation, and an ion beam mixing, and show that the surface modifications caused by these treatments are useful tools to modulate the sound press level. The ion implantations on various polymer diaphragms cause an increase in the resonant frequency so that the sound press level is lowered at low frequencies. On the contrary, a Cu or Fe 2 O 3 coating by using an ion beam mixing method causes a decrease in the resonant frequency, resulting in a high sound press level at low frequencies. We discuss the physical reasons for the change in the sound press level due to the ion-implantation methods.

  18. Analytical modeling of leak induced sound wave in a power plant boiler room

    International Nuclear Information System (INIS)

    Badsar, A.; Khosravi, F.

    2005-01-01

    An exact analysis for Sound propagation by a leak situated in a power plant boiler room is outlined. The Light hill model for description of free jet behavior along with the appropriate wave field expansions, the Neumann boundary conditions for boiler walls, and the classical theory of images are employed to develop a closed-form solution in form of infinite series. The analytical results are illustrated with numerical examples in which a leak in the boiler room produces spherical sound waves. The acoustic field pressure distribution is evaluated and discussed for representative values of the parameters characterizing the system. Limiting cases involving symmetric conditions of the problem are considered

  19. Emergence of category-level sensitivities in non-native speech sound learning

    Directory of Open Access Journals (Sweden)

    Emily eMyers

    2014-08-01

    Full Text Available Over the course of development, speech sounds that are contrastive in one’s native language tend to become perceived categorically: that is, listeners are unaware of variation within phonetic categories while showing excellent sensitivity to speech sounds that span linguistically meaningful phonetic category boundaries. The end stage of this developmental process is that the perceptual systems that handle acoustic-phonetic information show special tuning to native language contrasts, and as such, category-level information appears to be present at even fairly low levels of the neural processing stream. Research on adults acquiring non-native speech categories offers an avenue for investigating the interplay of category-level information and perceptual sensitivities to these sounds as speech categories emerge. In particular, one can observe the neural changes that unfold as listeners learn not only to perceive acoustic distinctions that mark non-native speech sound contrasts, but also to map these distinctions onto category-level representations. An emergent literature on the neural basis of novel and non-native speech sound learning offers new insight into this question. In this review, I will examine this literature in order to answer two key questions. First, where in the neural pathway does sensitivity to category-level phonetic information first emerge over the trajectory of speech sound learning? Second, how do frontal and temporal brain areas work in concert over the course of non-native speech sound learning? Finally, in the context of this literature I will describe a model of speech sound learning in which rapidly-adapting access to categorical information in the frontal lobes modulates the sensitivity of stable, slowly-adapting responses in the temporal lobes.

  20. Detection System of Sound Noise Level (SNL) Based on Condenser Microphone Sensor

    Science.gov (United States)

    Rajagukguk, Juniastel; Eka Sari, Nurdieni

    2018-03-01

    The research aims to know the noise level by using the Arduino Uno as data processing input from sensors and called as Sound Noise Level (SNL). The working principle of the instrument is as noise detector with the show notifications the noise level on the LCD indicator and in the audiovisual form. Noise detection using the sensor is a condenser microphone and LM 567 as IC op-amps, which are assembled so that it can detect the noise, which sounds are captured by the sensor will turn the tide of sinusoida voice became sine wave energy electricity (altering sinusoida electric current) that is able to responded to complaints by the Arduino Uno. The tool is equipped with a detector consists of a set indicator LED and sound well as the notification from the text on LCD 16*2. Work setting indicators on the condition that, if the measured noise > 75 dB then sound will beep, the red LED will light up indicating the status of the danger. If the measured value on the LCD is higher than 56 dB, sound indicator will be beep and yellow LED will be on indicating noisy. If the noise measured value <55 dB, sound indicator will be quiet indicating peaceful from noisy. From the result of the research can be explained that the SNL is capable to detecting and displaying noise level with a measuring range 50-100 dB and capable to delivering the notification noise in audiovisual.

  1. An integrated experimental and computational approach to material selection for sound proof thermally insulted enclosure of a power generation system

    Science.gov (United States)

    Waheed, R.; Tarar, W.; Saeed, H. A.

    2016-08-01

    Sound proof canopies for diesel power generators are fabricated with a layer of sound absorbing material applied to all the inner walls. The physical properties of the majority of commercially available sound proofing materials reveal that a material with high sound absorption coefficient has very low thermal conductivity. Consequently a good sound absorbing material is also a good heat insulator. In this research it has been found through various experiments that ordinary sound proofing materials tend to rise the inside temperature of sound proof enclosure in certain turbo engines by capturing the heat produced by engine and not allowing it to be transferred to atmosphere. The same phenomenon is studied by creating a finite element model of the sound proof enclosure and performing a steady state and transient thermal analysis. The prospects of using aluminium foam as sound proofing material has been studied and it is found that inside temperature of sound proof enclosure can be cut down to safe working temperature of power generator engine without compromise on sound proofing.

  2. Noise and noise disturbances from wind power plants - Tests with interactive control of sound parameters for more comfortable and less perceptible sounds

    International Nuclear Information System (INIS)

    Persson-Waye, K.; Oehrstroem, E.; Bjoerkman, M.; Agge, A.

    2001-12-01

    In experimental pilot studies, a methodology has been worked out for interactively varying sound parameters in wind power plants. In the tests, 24 persons varied the center frequency of different band-widths, the frequency of a sinus-tone and the amplitude-modulation of a sinus-tone in order to create as comfortable a sound as possible. The variations build on the noise from the two wind turbines Bonus and Wind World. The variations were performed with a constant dba level. The results showed that the majority preferred a low-frequency tone (94 Hz and 115 Hz for Wind World and Bonus, respectively). The mean of the most comfortable amplitude-modulation varied between 18 and 22 Hz, depending on the ground frequency. The mean of the center-frequency for the different band-widths varied from 785 to 1104 Hz. In order to study the influence of the wind velocity on the acoustic character of the noise, a long-time measurement program has been performed. A remotely controlled system has been developed, where wind velocity, wind direction, temperature and humidity are registered simultaneously with the noise. Long-time registrations have been performed for four different wing turbines

  3. Aging Affects Adaptation to Sound-Level Statistics in Human Auditory Cortex.

    Science.gov (United States)

    Herrmann, Björn; Maess, Burkhard; Johnsrude, Ingrid S

    2018-02-21

    Optimal perception requires efficient and adaptive neural processing of sensory input. Neurons in nonhuman mammals adapt to the statistical properties of acoustic feature distributions such that they become sensitive to sounds that are most likely to occur in the environment. However, whether human auditory responses adapt to stimulus statistical distributions and how aging affects adaptation to stimulus statistics is unknown. We used MEG to study how exposure to different distributions of sound levels affects adaptation in auditory cortex of younger (mean: 25 years; n = 19) and older (mean: 64 years; n = 20) adults (male and female). Participants passively listened to two sound-level distributions with different modes (either 15 or 45 dB sensation level). In a control block with long interstimulus intervals, allowing neural populations to recover from adaptation, neural response magnitudes were similar between younger and older adults. Critically, both age groups demonstrated adaptation to sound-level stimulus statistics, but adaptation was altered for older compared with younger people: in the older group, neural responses continued to be sensitive to sound level under conditions in which responses were fully adapted in the younger group. The lack of full adaptation to the statistics of the sensory environment may be a physiological mechanism underlying the known difficulty that older adults have with filtering out irrelevant sensory information. SIGNIFICANCE STATEMENT Behavior requires efficient processing of acoustic stimulation. Animal work suggests that neurons accomplish efficient processing by adjusting their response sensitivity depending on statistical properties of the acoustic environment. Little is known about the extent to which this adaptation to stimulus statistics generalizes to humans, particularly to older humans. We used MEG to investigate how aging influences adaptation to sound-level statistics. Listeners were presented with sounds drawn from

  4. Differences between Outdoor and Indoor Sound Levels for Open, Tilted, and Closed Windows.

    Science.gov (United States)

    Locher, Barbara; Piquerez, André; Habermacher, Manuel; Ragettli, Martina; Röösli, Martin; Brink, Mark; Cajochen, Christian; Vienneau, Danielle; Foraster, Maria; Müller, Uwe; Wunderli, Jean Marc

    2018-01-18

    Noise exposure prediction models for health effect studies normally estimate free field exposure levels outside. However, to assess the noise exposure inside dwellings, an estimate of indoor sound levels is necessary. To date, little field data is available about the difference between indoor and outdoor noise levels and factors affecting the damping of outside noise. This is a major cause of uncertainty in indoor noise exposure prediction and may lead to exposure misclassification in health assessments. This study aims to determine sound level differences between the indoors and the outdoors for different window positions and how this sound damping is related to building characteristics. For this purpose, measurements were carried out at home in a sample of 102 Swiss residents exposed to road traffic noise. Sound pressure level recordings were performed outdoors and indoors, in the living room and in the bedroom. Three scenarios-of open, tilted, and closed windows-were recorded for three minutes each. For each situation, data on additional parameters such as the orientation towards the source, floor, and room, as well as sound insulation characteristics were collected. On that basis, linear regression models were established. The median outdoor-indoor sound level differences were of 10 dB(A) for open, 16 dB(A) for tilted, and 28 dB(A) for closed windows. For open and tilted windows, the most relevant parameters affecting the outdoor-indoor differences were the position of the window, the type and volume of the room, and the age of the building. For closed windows, the relevant parameters were the sound level outside, the material of the window frame, the existence of window gaskets, and the number of windows.

  5. A Mathematical Images Group Model to Estimate the Sound Level in a Close-Fitting Enclosure

    Directory of Open Access Journals (Sweden)

    Michael J. Panza

    2014-01-01

    Full Text Available This paper describes a special mathematical images model to determine the sound level inside a close-fitting sound enclosure. Such an enclosure is defined as the internal air volume defined by a machine vibration noise source at one wall and a parallel reflecting wall located very close to it and acts as the outside radiating wall of the enclosure. Four smaller surfaces define a parallelepiped for the volume. The main reverberation group is between the two large parallel planes. Viewed as a discrete line-type source, the main group is extended as additional discrete line-type source image groups due to reflections from the four smaller surfaces. The images group approach provides a convergent solution for the case where hard reflective surfaces are modeled with absorption coefficients equal to zero. Numerical examples are used to calculate the sound pressure level incident on the outside wall and the effect of adding high absorption to the front wall. This is compared to the result from the general large room diffuse reverberant field enclosure formula for several hard wall absorption coefficients and distances between machine and front wall. The images group method is shown to have low sensitivity to hard wall absorption coefficient value and presents a method where zero sound absorption for hard surfaces can be used rather than an initial hard surface sound absorption estimate or measurement to predict the internal sound levels the effect of adding absorption.

  6. Predicting transmission of structure-borne sound power from machines by including terminal cross-coupling

    DEFF Research Database (Denmark)

    Ohlrich, Mogens

    2011-01-01

    strength and the prediction of power transmission to a supporting structure or the machine casing itself can be greatly simplified if all mobility cross-terms and spatial cross-coupling of source velocities can be neglected in the analysis. In many cases this gives an acceptable engineering accuracy......, especially at mid- and high-frequencies. For structurally compact machines, however, the influence of cross-coupling cannot always be ignored. The present paper addresses this problem and examines the transmission of structure-borne sound power by including spatial cross-coupling between pairs......Structure-borne sound generated by audible vibration of machines in vehicles, equipment and house-hold appliances is often a major cause of noise. Such vibration of complex machines is mostly determined and quantified by measurements. It has been found that characterization of the vibratory source...

  7. Artificial Heads for High-Level Impulse Sound Measurement

    National Research Council Canada - National Science Library

    Buck, K

    1999-01-01

    If the Insertion Loss (IL) of hearing protectors has to be determined with very high impulse or continuous noise levels, the acoustic insulation of the Artificial Test Fixture has to exceed at least the Insertion Loss (IL...

  8. Four odontocete species change hearing levels when warned of impending loud sound.

    Science.gov (United States)

    Nachtigall, Paul E; Supin, Alexander Ya; Pacini, Aude F; Kastelein, Ronald A

    2018-03-01

    Hearing sensitivity change was investigated when a warning sound preceded a loud sound in the false killer whale (Pseudorca crassidens), the bottlenose dolphin (Tursiops truncatus), the beluga whale (Delphinaperus leucas) and the harbor porpoise (Phocoena phocoena). Hearing sensitivity was measured using pip-train test stimuli and auditory evoked potential recording. When the test/warning stimuli preceded a loud sound, hearing thresholds before the loud sound increased relative to the baseline by 13 to 17 dB. Experiments with multiple frequencies of exposure and shift provided evidence of different amounts of hearing change depending on frequency, indicating that the hearing sensation level changes were not likely due to a simple stapedial reflex. © 2017 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  9. Sound level variation findings for pianissimo and fortissimo phonations in repeated measurements.

    Science.gov (United States)

    Sihvo, M; Sala, E

    1996-09-01

    Ten vocally untrained female university students vocalized /a:/ at five given pitches within the average female speaking range (196, 220, 262, 330, and 396 Hz) as softly as possible (pianissimo) and as loudly as musically acceptable (fortissimo). To study the repeatability of voice range profile (sound level) measurement, the procedure was repeated 10 times in each of the five sample sessions during the day, in connection with vocal loading that included five oral readings (45 min each), 15-min pauses, and a lunch break (45 min). A sound level meter specially designed for voice range profile measurement was used. The effect of the loading was seen on the mean sound level changes and intraindividual variation on SDs. The difference between the first phonation and best performance indicates significance of the repetition of the measurement. The sound level averaged across the pitches rose significantly during loading. The intraindividual SD varied between 3 and 4 dBA according to pitch and loudness, and the sound level difference between the first phonation and best performance was approximately 5 dBA in pianissimo and approximately 7 dBA in fortissimo.

  10. Exposure to classroom sound pressure level among dance teachers in Porto Alegre (RS).

    Science.gov (United States)

    Nehring, Cristiane; Bauer, Magda Aline; Teixeira, Adriane Ribeiro

    2013-01-01

     Dance teachers are exposed to high sound intensities. To verify the sound intensity of music used by dance teachers during classes.  This was a transversal and prospective study. Dance teachers were evaluated with a sociodemographic questionnaire, and sound intensity level measurements were taken at the beginning, middle, and end of dance classes.  The sample comprised 35 teachers (average age, 31.8 years). The duration of their career as dance teachers was 1-37 years; they worked daily for approximately 1-10 h. Among the classes followed, there were 15 (42.85%) classical ballet classes, 4 (11.42%) tap dancing lessons, 5 (14.28%) jazz dance classes, 2 (5.71) Arab dance lessons, 6 (17.14%) street dance classes, and 3 (8.57%) ballroom dancing lessons. The average values observed at the beginning, middle, and end of the classes were 80.91 dB (A), 83.22 dB (A), and 85.19 dB (A), respectively. The music played in the street dance classes exposed teachers to the highest sound intensity.  The average level of sound intensity of the dance classes in this study was either below or equal to the limit considered harmful for hearing health. Analysis of different class types showed that the sound densities of street, ballroom, and tap dance classes were above the recommended limits.

  11. Exposure to classroom sound pressure level among dance teachers in Porto Alegre (RS

    Directory of Open Access Journals (Sweden)

    Nehring, Cristiane

    2013-01-01

    Full Text Available Introduction: Dance teachers are exposed to high sound intensities. Aim: To verify the sound intensity of music used by dance teachers during classes. Method: This was a transversal and prospective study. Dance teachers were evaluated with a sociodemographic questionnaire, and sound intensity level measurements were taken at the beginning, middle, and end of dance classes. Results: The sample comprised 35 teachers (average age, 31.8 years. The duration of their career as dance teachers was 1-37 years; they worked daily for approximately 1-10 h. Among the classes followed, there were 15 (42.85% classical ballet classes, 4 (11.42% tap dancing lessons, 5 (14.28% jazz dance classes, 2 (5.71 Arab dance lessons, 6 (17.14% street dance classes, and 3 (8.57% ballroom dancing lessons. The average values observed at the beginning, middle, and end of the classes were 80.91 dB (A, 83.22 dB (A, and 85.19 dB (A, respectively. The music played in the street dance classes exposed teachers to the highest sound intensity. Conclusion: The average level of sound intensity of the dance classes in this study was either below or equal to the limit considered harmful for hearing health. Analysis of different class types showed that the sound densities of street, ballroom, and tap dance classes were above the recommended limits.

  12. Chronic scream sound exposure alters memory and monoamine levels in female rat brain.

    Science.gov (United States)

    Hu, Lili; Zhao, Xiaoge; Yang, Juan; Wang, Lumin; Yang, Yang; Song, Tusheng; Huang, Chen

    2014-10-01

    Chronic scream sound alters the cognitive performance of male rats and their brain monoamine levels, these stress-induced alterations are sexually dimorphic. To determine the effects of sound stress on female rats, we examined their serum corticosterone levels and their adrenal, splenic, and thymic weights, their cognitive performance and the levels of monoamine neurotransmitters and their metabolites in the brain. Adult female Sprague-Dawley rats, with and without exposure to scream sound (4h/day for 21 day) were tested for spatial learning and memory using a Morris water maze. Stress decreased serum corticosterone levels, as well as splenic and adrenal weight. It also impaired spatial memory but did not affect the learning ability. Monoamines and metabolites were measured in the prefrontal cortex (PFC), striatum, hypothalamus, and hippocampus. The dopamine (DA) levels in the PFC decreased but the homovanillic acid/DA ratio increased. The decreased DA and the increased 5-hydroxyindoleacetic acid (5-HIAA) levels were observed in the striatum. Only the 5-HIAA level increased in the hypothalamus. In the hippocampus, stress did not affect the levels of monoamines and metabolites. The results suggest that scream sound stress influences most physiologic parameters, memory, and the levels of monoamine neurotransmitter and their metabolites in female rats. Copyright © 2014. Published by Elsevier Inc.

  13. Measurement of the sound power incident on the walls of a reverberation room with near field acoustic holography

    DEFF Research Database (Denmark)

    Jacobsen, Finn; Tiana Roig, Elisabet

    2010-01-01

    area; and it has always been regarded as impossible to measure the sound power that is incident on a wall directly. This paper examines a new method of determining this quantity from sound pressure measurements at positions on the wall using 'statistically optimised near field acoustic holography...

  14. An analysis of collegiate band directors' exposure to sound pressure levels

    Science.gov (United States)

    Roebuck, Nikole Moore

    Noise-induced hearing loss (NIHL) is a significant but unfortunate common occupational hazard. The purpose of the current study was to measure the magnitude of sound pressure levels generated within a collegiate band room and determine if those sound pressure levels are of a magnitude that exceeds the policy standards and recommendations of the Occupational Safety and Health Administration (OSHA), and the National Institute of Occupational Safety and Health (NIOSH). In addition, reverberation times were measured and analyzed in order to determine the appropriateness of acoustical conditions for the band rehearsal environment. Sound pressure measurements were taken from the rehearsal of seven collegiate marching bands. Single sample t test were conducted to compare the sound pressure levels of all bands to the noise exposure standards of OSHA and NIOSH. Multiple regression analysis were conducted and analyzed in order to determine the effect of the band room's conditions on the sound pressure levels and reverberation times. Time weighted averages (TWA), noise percentage doses, and peak levels were also collected. The mean Leq for all band directors was 90.5 dBA. The total accumulated noise percentage dose for all band directors was 77.6% of the maximum allowable daily noise dose under the OSHA standard. The total calculated TWA for all band directors was 88.2% of the maximum allowable daily noise dose under the OSHA standard. The total accumulated noise percentage dose for all band directors was 152.1% of the maximum allowable daily noise dose under the NIOSH standards, and the total calculated TWA for all band directors was 93dBA of the maximum allowable daily noise dose under the NIOSH standard. Multiple regression analysis revealed that the room volume, the level of acoustical treatment and the mean room reverberation time predicted 80% of the variance in sound pressure levels in this study.

  15. Tutorial and Guidelines on Measurement of Sound Pressure Level in Voice and Speech

    Science.gov (United States)

    Švec, Jan G.; Granqvist, Svante

    2018-01-01

    Purpose: Sound pressure level (SPL) measurement of voice and speech is often considered a trivial matter, but the measured levels are often reported incorrectly or incompletely, making them difficult to compare among various studies. This article aims at explaining the fundamental principles behind these measurements and providing guidelines to…

  16. Sound Power Estimation for Beam and Plate Structures Using Polyvinylidene Fluoride Films as Sensors

    Science.gov (United States)

    Mao, Qibo; Zhong, Haibing

    2017-01-01

    The theory for calculation and/or measurement of sound power based on the classical velocity-based radiation mode (V-mode) approach is well established for planar structures. However, the current V-mode theory is limited in scope in that it can only be applied to conventional motion sensors (i.e., accelerometers). In this study, in order to estimate the sound power of vibrating beam and plate structure by using polyvinylidene fluoride (PVDF) films as sensors, a PVDF-based radiation mode (C-mode) approach concept is introduced to determine the sound power radiation from the output signals of PVDF films of the vibrating structure. The proposed method is a hybrid of vibration measurement and numerical calculation of C-modes. The proposed C-mode approach has the following advantages: (1) compared to conventional motion sensors, the PVDF films are lightweight, flexible, and low-cost; (2) there is no need for special measuring environments, since the proposed method does not require the measurement of sound fields; (3) In low frequency range (typically with dimensionless frequency kl < 4), the radiation efficiencies of the C-modes fall off very rapidly with increasing mode order, furthermore, the shapes of the C-modes remain almost unchanged, which means that the computation load can be significantly reduced due to the fact only the first few dominant C-modes are involved in the low frequency range. Numerical simulations and experimental investigations were carried out to verify the accuracy and efficiency of the proposed method. PMID:28509870

  17. A Organization for High-Level Interactive Programmatic Control of Computer-Generated Sound.

    Science.gov (United States)

    Das, Sumit

    The state of computer generated sound has advanced rapidly, and there exist many different ways of conceptualizing the abstract sound structures that comprise music and other complex organizations of sound. Many of these methods are radically different from one another, and so are not usually used within the same system. One problem that almost all methods share is one of control, as large amounts of data are needed to specify sounds. How do we create, examine, and modify these complex structures? The problem is exacerbated if we consider the realm of interactively controlled sound. This paper presents an organization which, rather than forcing a particular way of thinking about sound, allows multiple arbitrarily high-level views to coexist, all sharing a common interface. The methods or algorithms are abstracted into objects called auditory actors. This encapsulation allows different algorithms to be used concurrently. All communication with and between these actors is carried out through message-passing, which allows arbitrary types of information (such as other messages) to be easily communicated. This standardizes control without limiting it to a particular type of data. A prototype system was implemented using this model. This system was used by a number of different developers to create audio interfaces for interactive virtual reality applications, which were demonstrated at the SIGGRAPH 94 conference in Orlando, Florida. Compared to earlier systems, developers were able to create more complex audio interfaces in a shorter time.

  18. Pressure sound level measurements at an educational environment in Goiania, Goias, Brazil

    International Nuclear Information System (INIS)

    Costa, Jhonatha J.L.; Nascimento, Eriberto O. do; Oliveira, Lucas N. de; Caldas, Linda V. E.

    2017-01-01

    In this work, twenty five points located on the ground floor of the Federal Institute of Education, Science and Technology of Goias - IFG - Campus Goiania, were analyzed in morning periods of two Saturdays. The pressure sound levels were measured at internal and external environments during routine activities seeking to perform an environmental monitoring at this institution. The initial hypothesis was that an amusement park (Mutirama Park) was responsible for originating noise pollution in the institution, but the results showed, within the campus environment, sound pressure levels in accordance with the Municipal legislation of Goiania for all points. (author)

  19. Sound levels in a neonatal intensive care unit significantly exceeded recommendations, especially inside incubators.

    Science.gov (United States)

    Parra, Johanna; de Suremain, Aurelie; Berne Audeoud, Frederique; Ego, Anne; Debillon, Thierry

    2017-12-01

    This study measured sound levels in a 2008 built French neonatal intensive care unit (NICU) and compared them to the 2007 American Academy of Pediatrics (AAP) recommendations. The ultimate aim was to identify factors that could influence noise levels. The study measured sound in 17 single or double rooms in the NICU. Two dosimeters were installed in each room, one inside and one outside the incubators, and these conducted measurements over a 24-hour period. The noise metrics measured were the equivalent continuous sound level (L eq ), the maximum noise level (L max ) and the noise level exceeded for 10% of the measurement period (L 10 ). The mean L eq , L 10 and L max were 60.4, 62.1 and 89.1 decibels (dBA), which exceeded the recommended levels of 45, 50 and 65 dBA (p incubator was significantly higher than in the room (+8 dBA, p incubators. A multipronged strategy is required to improve the sound environment and protect the neonates' sensory development. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  20. Calculation and reduction of the sound emissions of overhead power lines

    International Nuclear Information System (INIS)

    Straumann, U.

    2007-01-01

    In this dissertation, Ulrich Straumann of the Swiss Federal Institute of Technology in Zurich, Switzerland, discusses the reduction of sound emissions from overhead power lines. Corona-discharges occur during wet weather or when foggy or icing conditions prevail. Apart from these wide-band crackling noises, low-frequency, tonal emissions also occur. The CONOR (Corona Noise Reduction) project examined these emissions at a frequency of twice the mains frequency and looked for economically feasible solutions to the problems caused by them. The source of these emissions and the mechanisms causing them are discussed. Also, ways of calculating their strength are presented. The effects of varying cable geometry and construction are discussed, as are hydrophilic coatings that could be used to reduce sound emissions.

  1. A Loudness Function for Maintaining Spectral Balance at Changing Sound Pressure Levels

    DEFF Research Database (Denmark)

    Nielsen, Sofus Birkedal

    . In this case the spectral balance will not be maintained. If the volume is turned up our perception for especially the low frequency will increase. If the level is increased 10dB from 90dB to 100 dB a 100 Hz tone will be perceived as +13 dB higher and 50 Hz as +14 dB higher, so an increasing bass boost. (+3 d...... of by the sound engineer by listening to the individual sound sources and adjust and equalize them to the wanted spectral balance including the whole chain of audio equipment and surroundings. At a live venue the sound pressure level will normally change during a concert, and typically increase over time...

  2. [The level of the musical loud sound and noise induced hearing impairment].

    Science.gov (United States)

    Ono, H; Deguchi, T; Ino, T; Okamoto, K; Takyu, H

    1986-03-20

    examined the relationship between these loud sound and noise induced temporary threshold shift (NITTS) in discotheques and noise proof room using simulation of loud sound exposure. Moreover, we measured the most comfortable loudness level of head phones in each examine and different types of music with environmental noise in consideration, thus examining the relationship between musical loud sound and the hearing impairment.

  3. Equivalent threshold sound pressure levels (ETSPL) for Interacoustics DD 45 supra-aural audiometric earphones

    DEFF Research Database (Denmark)

    Poulsen, Torben

    2010-01-01

    This paper describes the determination and results of pure tone Equivalent Threshold Sound Pressure Levels for the Interacoustics DD45 audiometric earphone equipped with standard Model 51 cushions. The size and shape of the DD45 transducer resembles the classical Telephonics TDH 39 earphone. Pure...

  4. Predicting transmission of structure-borne sound power from machines by including terminal cross-coupling

    Science.gov (United States)

    Ohlrich, Mogens

    2011-10-01

    Structure-borne sound generated by audible vibration of machines in vehicles, equipment and house-hold appliances is often a major cause of noise. Such vibration of complex machines is mostly determined and quantified by measurements. It has been found that characterization of the vibratory source strength and the prediction of power transmission to a supporting structure or the machine casing itself can be greatly simplified if all mobility cross-terms and spatial cross-coupling of source velocities can be neglected in the analysis. In many cases this gives an acceptable engineering accuracy, especially at mid- and high-frequencies. For structurally compact machines, however, the influence of cross-coupling cannot always be ignored. The present paper addresses this problem and examines the transmission of structure-borne sound power by including spatial cross-coupling between pairs of translational terminals in a global plane. This paired or bi-coupled power transmission represents the simplest case of cross-coupling. The procedure and quality of the predicted transmission using this improved technique is demonstrated experimentally for an electrical motor unit with an integrated radial fan that was mounted resiliently in a vacuum cleaner casing. It is found that cross-coupling plays a significant role, but only at frequencies below 100 Hz for the examined system.

  5. Weak Anderson localisation in reverberation rooms and its effect on the uncertainty of sound power measurements

    DEFF Research Database (Denmark)

    Jacobsen, Finn

    2011-01-01

    The effect known as ‘weak Anderson localisation’, ‘coherent backscattering’ or ‘enhanced backscattering’ is a physical phenomenon that occurs in random systems, e.g., disordered media and linear wave systems, including reverberation rooms: the mean square response is increased at the drive point...... position it is obviously very difficult to measure the effect directly. The ‘concentration factor’ is usually assumed to be 2, and the ‘modal kurtosis’ is assumed to be 3. This paper presents the results of an indirect experimental estimation of these two parameters, and discusses implications...... for the uncertainty of sound power measurements....

  6. Spatial and temporal determinants of A-weighted and frequency specific sound levels-An elastic net approach.

    Science.gov (United States)

    Walker, Erica D; Hart, Jaime E; Koutrakis, Petros; Cavallari, Jennifer M; VoPham, Trang; Luna, Marcos; Laden, Francine

    2017-11-01

    Urban sound levels are a ubiquitous environmental stressor and have been shown to be associated with a wide variety of health outcomes. While much is known about the predictors of A-weighted sound pressure levels in the urban environment, far less is known about other frequencies. To develop a series of spatial-temporal sound models to predict A-weighted sound pressure levels, low, mid, and high frequency sound for Boston, Massachusetts. Short-term sound levels were gathered at n = 400 sites from February 2015 - February 2016. Spatial and meteorological attributes at or near the sound monitoring site were obtained using publicly available data and a portable weather station. An elastic net variable selection technique was used to select predictors of A-weighted, low, mid, and high frequency sound. The final models for low, mid, high, and A-weighted sound levels explained 59 - 69% of the variability in each measure. Similar to other A-weighted models, our sound models included transportation related variables such as length of roads and bus lines in the surrounding area; distance to road and rail lines; traffic volume, vehicle mix, residential and commercial land use. However, frequency specific models highlighted additional predictors not included in the A-weighted model including temperature, vegetation, impervious surfaces, vehicle mix, and density of entertainment establishments and restaurants. Building spatial temporal models to characterize sound levels across the frequency spectrum using an elastic net approach can be a promising tool for noise exposure assessments within the urban soundscape. Models of sound's character may give us additional important sound exposure metrics to be utilized in epidemiological studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Preferred sound levels of portable music players and listening habits among adults: A field study

    Directory of Open Access Journals (Sweden)

    Kim R Kahari

    2011-01-01

    Full Text Available The main purpose of this descriptive field study was to explore music listening habits and preferred listening levels with portable music players (PMPs. We were also interested in seeing whether any exposure differences could be observed between the sexes. Data were collected during 12 hours at Stockholm Central Station, where people passing by were invited to measure their preferred PMP listening level by using a KEMAR manikin. People were also asked to answer a questionnaire about their listening habits. In all, 60 persons (41 men and 19 women took part in the questionnaire study and 61 preferred PMP levels to be measured. Forty-one of these sound level measurements were valid to be reported after consideration was taken to acceptable measuring conditions. The women (31 years and the men (33 years started to use PMPs on a regular basis in their early 20s. Ear canal headphones/ear buds were the preferred headphone types. Fifty-seven percent of the whole study population used their PMP on a daily basis. The measured LAeq60 sec levels corrected for free field ranged between 73 and 102 dB, with a mean value of 83 dB. Sound levels for different types of headphones are also presented. The results of this study indicate that there are two groups of listeners: people who listen less frequently and at lower, safer sound levels, and people with excessive listening habits that may indeed damage their hearing sensory organ in time.

  8. Low Power Design with High-Level Power Estimation and Power-Aware Synthesis

    CERN Document Server

    Ahuja, Sumit; Shukla, Sandeep Kumar

    2012-01-01

    Low-power ASIC/FPGA based designs are important due to the need for extended battery life, reduced form factor, and lower packaging and cooling costs for electronic devices. These products require fast turnaround time because of the increasing demand for handheld electronic devices such as cell-phones, PDAs and high performance machines for data centers. To achieve short time to market, design flows must facilitate a much shortened time-to-product requirement. High-level modeling, architectural exploration and direct synthesis of design from high level description enable this design process. This book presents novel research techniques, algorithms,methodologies and experimental results for high level power estimation and power aware high-level synthesis. Readers will learn to apply such techniques to enable design flows resulting in shorter time to market and successful low power ASIC/FPGA design. Integrates power estimation and reduction for high level synthesis, with low-power, high-level design; Shows spec...

  9. [Preventive effects of sound insulation windows on the indoor noise levels in a street residential building in Beijing].

    Science.gov (United States)

    Guo, Bin; Huang, Jing; Guo, Xin-biao

    2015-06-18

    To evaluate the preventive effects of sound insulation windows on traffic noise. Indoor noise levels of the residential rooms (on both the North 4th ring road side and the campus side) with closed sound insulation windows were measured using the sound level meter, and comparisons with the simultaneously measured outdoor noise levels were made. In addition, differences of indoor noise levels between rooms with closed sound insulation windows and open sound insulation windows were also compared. The average outdoor noise levels of the North 4th ring road was higher than 70 dB(A), which exceeded the limitation stated in the "Environmental Quality Standard for Noise" (GB 3096-2008) in our country. However, with the sound insulation windows closed, the indoor noise levels reduced significantly to the level under 35 dB(A) (Pwindows had significant influence on the indoor noise levels (Pwindow, when the sound insulation windows were closed, the indoor noise levels reduced 18.8 dB(A) and 8.3 dB(A) in residential rooms facing North 4th ring road side and campus side, respectively. The results indicated that installation of insulation windows had significant noise reduction effects on street residential buildings especially on the rooms facing major traffic roads. Installation of the sound insulation windows has significant preventive effects on indoor noise in the street residential building.

  10. Sound pressure level variations across the Pacific based on IMS data

    Science.gov (United States)

    Yamada, Tomoaki; Haralabus, Georgios; Zampolli, Mario; Heaney, Kevin

    2017-04-01

    Low frequency hydro-acoustic waves can be detected at great distances due to low attenuation of acoustic energy in the SOund Fixing And Ranging (SOFAR) channel. These waves contain both acoustic source and propagation medium information which is difficult to separate at the receiving end. This study examines sound pressure level variations across the pacific using 100 underwater controlled sources near a landward slope zone in Japan to minimize source uncertainty. The data were acquired at water-column hydrophones of the hydroacoustic station HA03 at Chile that is part of the International Monitoring System (IMS) of the Comprehensive Nuclear Test Ban Treaty. Acoustics waves were detected over 15,000 km across the Pacific and initial analysis indicates a maximum difference of the pressure level is 17 dB re. micro Pa.

  11. Behind Start of Take-Off Roll Aircraft Sound Level Directivity Study - Revision 1

    Science.gov (United States)

    Lau, Michael C.; Roof, Christopher J.; Fleming, Gregg G.; Rapoza, Amanda S.; Boeker, Eric R.; McCurdy, David A.; Shepherd, Kevin P.

    2015-01-01

    The National Aeronautics and Space Administration (NASA), Langley Research Center (LaRC) and the Environmental Measurement and Modeling Division of the Department of Transportation's Volpe National Transportation Systems Center (Volpe) conducted a noise measurement study to examine aircraft sound level directivity patterns behind the start-of-takeoff roll. The study was conducted at Washington Dulles International Airport (IAD) from October 4 through 20, 2004.

  12. A Hearing-Based, Frequency Domain Sound Quality Model for Combined Aerodynamic and Power Transmission Response with Application to Rotorcraft Interior Noise

    Science.gov (United States)

    Sondkar, Pravin B.

    The severity of combined aerodynamics and power transmission response in high-speed, high power density systems such as a rotorcraft is still a major cause of annoyance in spite of recent advancement in passive, semi-active and active control. With further increase in the capacity and power of this class of machinery systems, the acoustic noise levels are expected to increase even more. To achieve further improvements in sound quality, a more refined understanding of the factors and attributes controlling human perception is needed. In the case of rotorcraft systems, the perceived quality of the interior sound field is a major determining factor of passenger comfort. Traditionally, this sound quality factor is determined by measuring the response of a chosen set of juries who are asked to compare their qualitative reactions to two or more sounds based on their subjective impressions. This type of testing is very time-consuming, costly, often inconsistent, and not useful for practical design purposes. Furthermore, there is no known universal model for sound quality. The primary aim of this research is to achieve significant improvements in quantifying the sound quality of combined aerodynamic and power transmission response in high-speed, high power density machinery systems such as a rotorcraft by applying relevant objective measures related to the spectral characteristics of the sound field. Two models have been proposed in this dissertation research. First, a classical multivariate regression analysis model based on currently known sound quality metrics as well some new metrics derived in this study is presented. Even though the analysis resulted in the best possible multivariate model as a measure of the acoustic noise quality, it lacks incorporation of human judgment mechanism. The regression model can change depending on specific application, nature of the sounds and types of juries used in the study. Also, it predicts only the averaged preference scores and

  13. Evaluation of an abutment-level superpower sound processor for bone-anchored hearing.

    Science.gov (United States)

    Bosman, A J; Kruyt, I J; Mylanus, E A M; Hol, M K S; Snik, A F M

    2018-02-16

    Performance of an abutment-level superpower sound processor for bone-anchored hearing, the Ponto 3 SuperPower from Oticon Medical (BCD2), was compared to an earlier model from Oticon Medical (BCD1). A comparative study in which each patient serves as its own control. Tertiary clinic. Eighteen experienced BCD1 users with profound mixed hearing loss. Speech reception thresholds in noise; APHAB and SSQ questionnaires. In a group of 18 patients with severe mixed hearing loss, the performance of a recently introduced bone conduction device (BCD2) is evaluated relative to that of an earlier model (BCD1). Speech reception thresholds for the sentence-in-noise test in the speech and noise frontal condition are not significantly different (P > .05) for BCD1 and BCD2. Speech reception thresholds for frontal speech and three identical noise sources are 1.7 dB lower for BCD2 than for BCD1 (P  .05). Scores for the speech, spatial and quality of hearing domains of the SSQ questionnaire are significantly higher (P < .01), that is more favourable, for BCD2 than for BCD1 with effect sizes of 1.22, 0.71 and 1.05, respectively. Scores for the SSQ-factors "speech understanding," "spatial," "clarity, separation and identification" and "listening effort and concentration" were all significantly higher (P < .05) for BCD2 than for BCD1, with effect sizes of 1.28, 0.64, 0.98 and 0.78, respectively. On a proprietary questionnaire, 16 patients indicate a preference for BCD2 over BCD1 for conversations in a small group and two patients have no preference for either device. In a large group, one patient prefers BCD1, six patients have no preference, and eleven patients prefer BCD2. When listening to music, all patients prefer BCD2 over BCD1, with a strong preference for BCD2 for seven patients. When asked for an overall preference, all patients prefer BCD2 over BCD1, with nine patients strongly preferring BCD2. The lower speech reception thresholds in noise with BCD2 relative to BCD1

  14. Assessment and evaluation of noise controls on roof bolting equipment and a method for predicting sound pressure levels in underground coal mining

    Science.gov (United States)

    Matetic, Rudy J.

    Over-exposure to noise remains a widespread and serious health hazard in the U.S. mining industries despite 25 years of regulation. Every day, 80% of the nation's miners go to work in an environment where the time weighted average (TWA) noise level exceeds 85 dBA and more than 25% of the miners are exposed to a TWA noise level that exceeds 90 dBA, the permissible exposure limit (PEL). Additionally, MSHA coal noise sample data collected from 2000 to 2002 show that 65% of the equipment whose operators exceeded 100% noise dosage comprise only seven different types of machines; auger miners, bulldozers, continuous miners, front end loaders, roof bolters, shuttle cars (electric), and trucks. In addition, the MSHA data indicate that the roof bolter is third among all the equipment and second among equipment in underground coal whose operators exceed 100% dosage. A research program was implemented to: (1) determine, characterize and to measure sound power levels radiated by a roof bolting machine during differing drilling configurations (thrust, rotational speed, penetration rate, etc.) and utilizing differing types of drilling methods in high compressive strength rock media (>20,000 psi). The research approach characterized the sound power level results from laboratory testing and provided the mining industry with empirical data relative to utilizing differing noise control technologies (drilling configurations and types of drilling methods) in reducing sound power level emissions on a roof bolting machine; (2) distinguish and correlate the empirical data into one, statistically valid, equation, in which, provided the mining industry with a tool to predict overall sound power levels of a roof bolting machine given any type of drilling configuration and drilling method utilized in industry; (3) provided the mining industry with several approaches to predict or determine sound pressure levels in an underground coal mine utilizing laboratory test results from a roof bolting

  15. Hearing performance benefits of a programmable power baha® sound processor with a directional microphone for patients with a mixed hearing loss.

    Science.gov (United States)

    Flynn, Mark C; Hedin, Annelen; Halvarsson, Glenn; Good, Tobias; Sadeghi, Andre

    2012-04-01

    New signal processing technologies have recently become available for Baha® sound processors. These technologies have led to an increase in power and to the implementation of directional microphones. For any new technology, it is important to evaluate the degree of benefit under different listening situations. Twenty wearers of the Baha osseointegrated hearing system participated in the investigation. The control sound processor was the Baha Intenso and the test sound processor was the Cochlear™ Baha® BP110power. Performance was evaluated in terms of free-field audibility with narrow band noise stimuli. Speech recognition of monosyllabic phonetically balanced (PB) words in quiet was performed at three intensity settings (50, 65, and 80 dB sound pressure level [SPL]) with materials presented at 0 degrees azimuth. Speech recognition of sentences in noise using the Hearing in Noise Test (HINT) in an adaptive framework was performed with speech from 0 degrees and noise held constant at 65 dB SPL from 180 degrees. Testing was performed in both the omni and directional microphone settings. Loudness growth was assessed in randomly presented 10 dB steps between 30 and 90 dB SPL to narrow band noise stimuli at 500 Hz and 3,000 Hz. The test sound processor had significantly improved high frequency audibility (3,000-8,000 Hz). Speech recognition of PB words in quiet at three different intensity levels (50, 65, and 80 dB SPL) indicated a significant difference in terms of level (Pprocessor type (P>0.05). Speech recognition of sentences in noise demonstrated a 2.5 dB signal-to-noise ratio (SNR) improvement in performance for the test sound processor. The directional microphone provided an additional 2.3 dB SNR improvement in speech recognition (Pprocessors had sufficient headroom and amplification for the required hearing loss. The test sound processor demonstrated significant improvements in the most challenging listening situation (speech recognition in noise). The

  16. Winter sound-level characterization of the Deaf Smith County location in the Palo Duro Basin, Texas

    International Nuclear Information System (INIS)

    1984-03-01

    A description of sound levels and sound sources in the Deaf Smith County location in the Palo Duro Basin during a period representative of the winter season is presented. Data were collected during the period February 26 through March 1, 1983. 4 references, 1 figure, 3 tables

  17. Summer sound-level characterization of the Deaf Smith County and Swisher County locations in the Palo Duro Basin, Texas

    International Nuclear Information System (INIS)

    1984-03-01

    A description of sound levels and sound sources in the Deaf Smith County and Swisher County locations in the Palo Duro Basin during a period representative of the summer season is presented. Included are data collected during the period August 4 through 8, 1982, for both locations. 3 references, 2 figures, 3 tables

  18. A further test of relevance of ASEL and CSEL in the determination of the rating sound level for shooting sounds

    NARCIS (Netherlands)

    Vos, J.

    1998-01-01

    In a previous study on the annoyance caused by shooting sounds [Proceedings Internoise '96, Vol. 5, 2231-2236], it was shown that an almost perfect prediction of the annoyance, as rated indoors with the windows closed, was obtained on the basis of the weighted sum of the outdoor A-weighted and

  19. A comparative analysis at engineering level of dispersive and Fourier transform spectrometers for MTG sounding applications

    Science.gov (United States)

    Quatrevalet, Mathieu; Aminou, Donny; Bézy, Jean-Loup

    2017-11-01

    Sounding measurements with high spatial resolution (better than 10 km horizontal and 1 km vertical) and repeat cycles better than an hour over the full Earth disk will enhance the ability of National Meteorological Services to initialise models of observations of temperature, moisture and winds. To meet those needs, trade-off's were performed during the Meteosat Third Generation (MTG) mission study (2003-2005) where preliminary instrument concepts for the Infra-Red Sounding (IRS) mission were investigated allowing at the same time to consolidate the technical requirements for the overall system study. The trade-off's demonstrated that two types of instrument could fulfill the requirements: a Fourier Transform Spectrometer and a Dispersive Spectrometer. This paper aims at comparing these two MTG-IRS sensor concepts by highlighting the differences in the constraints imposed on the characteristics and required performance at hardware level. In addition, technology criticalities and some other aspects are discussed qualitatively.

  20. Intra-subject variability of snoring sounds in relation to body position, sleep stage, and blood oxygen level.

    Science.gov (United States)

    Azarbarzin, Ali; Moussavi, Zahra

    2013-04-01

    In a multidimensional feature space, the snoring sounds can extend from a very compact cluster to highly distinct clusters. In this study, we investigated the cause of snoring sound's variation within the snorers. It is known that a change in body position and sleep stage can affect snoring during sleep but it is unclear whether positional, sleep state, and blood oxygen level variations cause the snoring sounds to have different characteristics, and if it does how significant that effect would be. We extracted 12 characteristic features from snoring sound segments of 57 snorers and transformed them into a 4-D feature space using principal component analysis (PCA). Then, they were grouped based on the body position (side, supine, and prone), sleep stage (NREM, REM, and Arousal), and blood oxygen level (Normal and Desaturation). The probability density function of the transformed features was calculated for each class of categorical variables. The distance between the class-densities were calculated to determine which of these parameters affects the snoring sounds significantly. Analysis of Variance (ANOVA) was run for each categorical variable. The results show that the positional change has the highest effect on the snoring sounds; it results in forming distinct clusters of snoring sounds. Also, sleep state and blood oxygen level variation have been found to moderately affect the snoring sounds.

  1. Measurements of inter-cochlear level and phase differences of bone-conducted sound

    Science.gov (United States)

    Mcleod, Robert W. J.; Culling, John F.

    2017-01-01

    Bone-anchored hearing aids are a widely used method of treating conductive hearing loss, but the benefit of bilateral implantation is limited due to interaural cross-talk. The present study measured the phase and level of pure tones reaching each cochlea from a single, mastoid placed bone transducer on normal hearing participants. In principle, the technique could be used to implement a cross-talk cancellation system in those with bilateral bone conductors. The phase and level of probe tones over two insert earphones was adjusted until they canceled sound from a bone transducer (i.e., resulting in perceived silence). Testing was performed in 50-Hz steps between 0.25 and 8 kHz. Probe phase and level results were used to calculate inter-cochlear level and phase differences. The inter-cochlear phase differences of the bone-conducted sound were similar for all three participants showing a relatively linear increase between 4 and 8 kHz. The attenuation characteristics were highly variable over the frequency range as well as between participants. This variability was thought to be related to differences in skull dynamics across the ears. Repeated measurements of cancellation phase and level of the same frequency produced good consistency across sessions from the same participant. PMID:28599562

  2. Equivalent threshold sound pressure levels for acoustic test signals of short duration

    DEFF Research Database (Denmark)

    Poulsen, Torben; Daugaard, Carsten

    1998-01-01

    . The measurements were performed with two types of headphones, Telephonics TDH-39 and Sennheiser HDA-200. The sound pressure levels were measured in an IEC 318 ear simulator with Type 1 adapter (a flat plate) and a conical ring. The audiometric methods used in the experiments were the ascending method (ISO 8253......-1) and a transformed up/down procedure. Twenty-eight normal hearing test subjects (13 females and 15 males) in the age range from 18 to 26 years participated in the experiments. The results of this investigation will be used in standardisation (ISO/TC43/WG1)....

  3. [The influence factors of sound pressure level parameters in patients with simple snoring and obstructive sleep apnea hypopnea syndrom].

    Science.gov (United States)

    Gao, Zhan; Xu, Huijie; Huang, Weining; Peng, Hao; He, Yuxia

    2015-06-01

    To discuss the main influence factors of sound pressure level parameters in patients with simple snoring (SS) and obstructive sleep apnea hypopnea syndrom (OSAHS). Eighty-four cases with snoring disease underwent polysomnography and simultaneously snoring sound pressure level recording. The correlations between AHI, age, BMI, abdomen circumference, neck circumference, the lowest oxygen saturation total apnea time and sound pressure level parameters: equivalent continuous sound level(LAeq)and maximum sound pressure level(L10) were analyzed. LAeq was significantly correlated to AHI (P= 0. 000) and BMI (P= 0. 007), and the odd ratios of AHI and BMI were 5. 74,2. 09 respectively, but it was unrelated to age, abdomen circumference, neck circumference, the lowest oxygen saturation and total apnea time. A significantly association also existed between L10 and AHI(P=0. 000), BMI(P=0. 032), and the odd ratios were 4. 11 and 2. 33 respectively. Other factors had nothing to do with L10. The main factors which affect the snoring sound pressure level parameters LAeq and L10 are AHI and BMI.

  4. Frequency electromagnetic sounding with industrial power lines on Karelia-Kola geotraverse

    Directory of Open Access Journals (Sweden)

    А. Н. Шевцов

    2017-04-01

    Full Text Available The paper describes theory, method and first experimental results of research on the interaction between electromagnetic waves of extremely low and ultra low frequency (0.1-200 Hz, the Earth crust and ionosphere in the field of two mutually orthogonal industrial power lines, 109 and 120 km long, in the course of FENICS experiment (Fennoscandian Electrical conductivity from Natural and Induction Control Source soundings. The main focus was on the observation results along the line of Karelia-Kola geotraverse over a distance of 700 km from the source. High horizontal homogeneity of geoelectrical lithosphere section has been detected in the eastern part of the Baltic shield at depth range from 10-15 to 50-70 km. Parameters of «regular» lithosphere section have been specified to the depth of 60-70 km. As a result of inverse problem solution for the western part of Karelia and Central Finland, a zone of decreased transverse resistivity has been detected at the depth of 50-60 km, corresponding to the area, detected by seismic methods, where Moho boundary reaches the same depth.

  5. Sources and levels of ambient ocean sound near the Antarctic Peninsula.

    Directory of Open Access Journals (Sweden)

    Robert P Dziak

    Full Text Available Arrays of hydrophones were deployed within the Bransfield Strait and Scotia Sea (Antarctic Peninsula region from 2005 to 2009 to record ambient ocean sound at frequencies of up to 125 and 500 Hz. Icequakes, which are broadband, short duration signals derived from fracturing of large free-floating icebergs, are a prominent feature of the ocean soundscape. Icequake activity peaks during austral summer and is minimum during winter, likely following freeze-thaw cycles. Iceberg grounding and rapid disintegration also releases significant acoustic energy, equivalent to large-scale geophysical events. Overall ambient sound levels can be as much as ~10-20 dB higher in the open, deep ocean of the Scotia Sea compared to the relatively shallow Bransfield Strait. Noise levels become lowest during the austral winter, as sea-ice cover suppresses wind and wave noise. Ambient noise levels are highest during austral spring and summer, as surface noise, ice cracking and biological activity intensifies. Vocalizations of blue (Balaenoptera musculus and fin (B. physalus whales also dominate the long-term spectra records in the 15-28 and 89 Hz bands. Blue whale call energy is a maximum during austral summer-fall in the Drake Passage and Bransfield Strait when ambient noise levels are a maximum and sea-ice cover is a minimum. Fin whale vocalizations were also most common during austral summer-early fall months in both the Bransfield Strait and Scotia Sea. The hydrophone data overall do not show sustained anthropogenic sources (ships and airguns, likely due to low coastal traffic and the typically rough weather and sea conditions of the Southern Ocean.

  6. Evaluation of the effects of various sound pressure levels on the level of serum aldosterone concentration in rats

    Directory of Open Access Journals (Sweden)

    Parvin Nassiri

    2017-01-01

    Full Text Available Introduction: Noise exposure may have anatomical, nonauditory, and auditory influences. Considering nonauditory impacts, noise exposure can cause alterations in the automatic nervous system, including increased pulse rates, heightened blood pressure, and abnormal secretion of hormones. The present study aimed at examining the effect of various sound pressure levels (SPLs on the serum aldosterone level among rats. Materials and Methods: A total of 45 adult male rats with an age range of 3 to 4 months and a weight of 200 ± 50 g were randomly divided into 15 groups of three. Three groups were considered as the control groups and the rest (i.e., 12 groups as the case groups. Rats of the case groups were exposed to SPLs of 85, 95, and 105 dBA. White noise was used as the noise to which the rats were exposed. To measure the level of rats’ serum aldosterone, 3 mL of each rat’s sample blood was directly taken from the heart of anesthetized animals by using syringes. The taken blood samples were put in labeled test tubes that contained anticoagulant Ethylenediaminetetraacetic acid. In the laboratory, the level of aldosterone was assessed through Enzyme-linked immunosorbent assay protocol. The collected data were analyzed by the use of Statistical Package for Social Sciences (SPSS version 18. Results: The results revealed that there was no significant change in the level of rats’ serum aldosterone as a result of exposure to SPLs of 65, 85, and 95 dBA. However, the level of serum aldosterone experienced a remarkable increase after exposure to the SPL of 105 dBA (P < 0.001. Thus, the SPL had a significant impact on the serum aldosterone level (P < 0.001. In contrast, the exposure time and the level of potassium in the used water did not have any measurable influence on the level of serum aldosterone (P = 0.25 and 0.39. Conclusion: The findings of this study demonstrated that serum aldosterone can be used as a biomarker in the face of sound

  7. Attenuation of peak sound pressure levels of shooting noise by hearing protective earmuffs

    Directory of Open Access Journals (Sweden)

    Paolo Lenzuni

    2012-01-01

    Full Text Available Transmission losses (TL to highly impulsive signals generated by three firearms have been measured for two ear muffs, using both a head and torso simulator and a miniature microphone located at the ear canal entrance (MIRE technique. Peak SPL TL have been found to be well approximated by 40 ms short-L eq TL. This has allowed the use of transmissibilities and correction factors for bone conduction and physiological masking appropriate for continuous noise, for the calculation of REAT-type peak insertion losses (IL. Results indicate that peak IL can be well predicted by estimates based on one-third octave band 40 ms short L eq and manufacturer-declared (nominal IL measured for continuous noise according to test standards. Such predictions tend to be more accurate at the high end of the range, while they are less reliable when the attenuation is lower. A user-friendly simplified prediction algorithm has also been developed, which only requires nominal IL and one-third octave sound exposure level spectra. Separate predictions are possible for IL in direct and diffuse sound fields, albeit with higher uncertainties, due to the smaller number of experimental data comprising the two separate datasets on which such predictions are based.

  8. Ultrathin, rollable, paper-based triboelectric nanogenerator for acoustic energy harvesting and self-powered sound recording.

    Science.gov (United States)

    Fan, Xing; Chen, Jun; Yang, Jin; Bai, Peng; Li, Zhaoling; Wang, Zhong Lin

    2015-04-28

    A 125 μm thickness, rollable, paper-based triboelectric nanogenerator (TENG) has been developed for harvesting sound wave energy, which is capable of delivering a maximum power density of 121 mW/m(2) and 968 W/m(3) under a sound pressure of 117 dBSPL. The TENG is designed in the contact-separation mode using membranes that have rationally designed holes at one side. The TENG can be implemented onto a commercial cell phone for acoustic energy harvesting from human talking; the electricity generated can be used to charge a capacitor at a rate of 0.144 V/s. Additionally, owing to the superior advantages of a broad working bandwidth, thin structure, and flexibility, a self-powered microphone for sound recording with rolled structure is demonstrated for all-sound recording without an angular dependence. The concept and design presented in this work can be extensively applied to a variety of other circumstances for either energy-harvesting or sensing purposes, for example, wearable and flexible electronics, military surveillance, jet engine noise reduction, low-cost implantable human ear, and wireless technology applications.

  9. Sound pressure levels generated at risk volume steps of portable listening devices: types of smartphone and genres of music.

    Science.gov (United States)

    Kim, Gibbeum; Han, Woojae

    2018-05-01

    The present study estimated the sound pressure levels of various music genres at the volume steps that contemporary smartphones deliver, because these levels put the listener at potential risk for hearing loss. Using six different smartphones (Galaxy S6, Galaxy Note 3, iPhone 5S, iPhone 6, LG G2, and LG G3), the sound pressure levels for three genres of K-pop music (dance-pop, hip-hop, and pop-ballad) and a Billboard pop chart of assorted genres were measured through an earbud for the first risk volume that was at the risk sign proposed by the smartphones, as well as consecutive higher volumes using a sound level meter and artificial mastoid. The first risk volume step of the Galaxy S6 and the LG G2, among the six smartphones, had the significantly lowest (84.1 dBA) and highest output levels (92.4 dBA), respectively. As the volume step increased, so did the sound pressure levels. The iPhone 6 was loudest (113.1 dBA) at the maximum volume step. Of the music genres, dance-pop showed the highest output level (91.1 dBA) for all smartphones. Within the frequency range of 20~ 20,000 Hz, the sound pressure level peaked at 2000 Hz for all the smartphones. The results showed that the sound pressure levels of either the first volume step or the maximum volume step were not the same for the different smartphone models and genres of music, which means that the risk volume sign and its output levels should be unified across the devices for their users. In addition, the risk volume steps proposed by the latest smartphone models are high enough to cause noise-induced hearing loss if their users habitually listen to music at those levels.

  10. EFFECT OF NATURE SOUND THERAPY ON THE LEVEL OF CORTISOL IN POSTPARTUM PRIMIPARA

    Directory of Open Access Journals (Sweden)

    Yulinda Laska

    2018-02-01

    Full Text Available Background: Prevalence of postpartum blues for Asia between 26-85%, while the prevalence in Indonesia is 50-70%. Of all women postpartum can experience this is experiencing stress, almost 80% of primiparous moms experience feelings of sadness after childbirth. These stresses can trigger an increase in cortisol. Music raises changes in brain wave status and stress hormones. Nature Sound music is music that has a slow tempo and can cause feelings relaxed and comfortable. Objective: To examine the effect of the nature music therapy on on cortisol levels in postpartum primipara. Methods: This was a true experimental study with pretest-posttest control group design. The study was conducted in the postpartum ward in the General Hospital of Semarang from November 2016 to January 2017. There were 39 postpartum primipara recruited in this study using simple random sampling divided into three groups: 1 the experiment group who received the nature music therapy for 15 minutes, 2 the experiment group who received the nature music therapy for 30 minutes, and 3 the control group. One-way ANOVA test was performed for data analysis. Results: One-way anova test showed p-value 0.010 (<0.05, which indicated that there was a statistically significant effect of the nature sound therapy on the cortisol level in the postpartum primipara. Conclusion: There was a significant effect of the nature music therapy on the cortisol levels in postpartum primipara. Thus, the application of nature music therapy can be an alternative therapy especially for postpartum primipara who experience emotional stress, physical, anxiety, and fatigue.

  11. Matched Behavioral and Neural Adaptations for Low Sound Level Echolocation in a Gleaning Bat,Antrozous pallidus.

    Science.gov (United States)

    Measor, Kevin R; Leavell, Brian C; Brewton, Dustin H; Rumschlag, Jeffrey; Barber, Jesse R; Razak, Khaleel A

    2017-01-01

    In active sensing, animals make motor adjustments to match sensory inputs to specialized neural circuitry. Here, we describe an active sensing system for sound level processing. The pallid bat uses downward frequency-modulated (FM) sweeps as echolocation calls for general orientation and obstacle avoidance. The bat's auditory cortex contains a region selective for these FM sweeps (FM sweep-selective region, FMSR). We show that the vast majority of FMSR neurons are sensitive and strongly selective for relatively low levels (30-60 dB SPL). Behavioral testing shows that when a flying bat approaches a target, it reduces output call levels to keep echo levels between ∼30 and 55 dB SPL. Thus, the pallid bat behaviorally matches echo levels to an optimized neural representation of sound levels. FMSR neurons are more selective for sound levels of FM sweeps than tones, suggesting that across-frequency integration enhances level tuning. Level-dependent timing of high-frequency sideband inhibition in the receptive field shapes increased level selectivity for FM sweeps. Together with previous studies, these data indicate that the same receptive field properties shape multiple filters (sweep direction, rate, and level) for FM sweeps, a sound common in multiple vocalizations, including human speech. The matched behavioral and neural adaptations for low-intensity echolocation in the pallid bat will facilitate foraging with reduced probability of acoustic detection by prey.

  12. Acoustic characterization of a nonlinear vibroacoustic absorber at low frequencies and high sound levels

    Science.gov (United States)

    Chauvin, A.; Monteil, M.; Bellizzi, S.; Côte, R.; Herzog, Ph.; Pachebat, M.

    2018-03-01

    A nonlinear vibroacoustic absorber (Nonlinear Energy Sink: NES), involving a clamped thin membrane made in Latex, is assessed in the acoustic domain. This NES is here considered as an one-port acoustic system, analyzed at low frequencies and for increasing excitation levels. This dynamic and frequency range requires a suitable experimental technique, which is presented first. It involves a specific impedance tube able to deal with samples of sufficient size, and reaching high sound levels with a guaranteed linear response thank's to a specific acoustic source. The identification method presented here requires a single pressure measurement, and is calibrated from a set of known acoustic loads. The NES reflection coefficient is then estimated at increasing source levels, showing its strong level dependency. This is presented as a mean to understand energy dissipation. The results of the experimental tests are first compared to a nonlinear viscoelastic model of the membrane absorber. In a second step, a family of one degree of freedom models, treated as equivalent Helmholtz resonators is identified from the measurements, allowing a parametric description of the NES behavior over a wide range of levels.

  13. Nuclear power and low level radiation hazards

    International Nuclear Information System (INIS)

    Myers, D.K.; Newcombe, H.B.

    1979-03-01

    Even in the future, nuclear power is expected to contribute less than 1/10th of the present total population exposure to man-made radiation. By the best estimates available, the current health risks of nuclear power generation appear to be much less than those associated with the major alternative sources of energy, with the exception of natural gas which is about equally safe. Uncertainties concerning the radiation risks from nuclear power, from medical x-rays and from the effects of reduced ventillation to conserve heat appear to be less than those associated with estimates of risks from the use of coal and various other sources of energy. This is in part because of the large amount of effort devoted to studies of radiation effects. The benefits in terms of current life expectancy associated with any of the conventional or unconventional methods of power production appear to greatly outweigh the associated current health hazards. (author)

  14. Dolphin foraging sounds suppress calling and elevate stress hormone levels in a prey species, the Gulf toadfish.

    Science.gov (United States)

    Remage-Healey, Luke; Nowacek, Douglas P; Bass, Andrew H

    2006-11-01

    The passive listening hypothesis proposes that dolphins and whales detect acoustic signals emitted by prey, including sound-producing (soniferous) fishes. Previous work showed that bottlenose dolphins (Tursiops truncatus) behaviorally orient toward the sounds of prey, including the advertisement calls of male Gulf toadfish (Opsanus beta). In addition, soniferous fishes constitute over 80% of Tursiops diet, and toadfishes alone account for approximately 13% of the stomach contents of adult bottlenose dolphins. Here, we used both behavioral (vocalizations) and physiological (plasma cortisol levels) parameters to determine if male Gulf toadfish can, in turn, detect the acoustic signals of bottlenose dolphins. Using underwater playbacks to toadfish in their natural environment, we found that low-frequency dolphin sounds (;pops') within the toadfish's range of hearing dramatically reduce toadfish calling rates by 50%. High frequency dolphin sounds (whistles) and low-frequency snapping shrimp pops (ambient control sounds) each had no effect on toadfish calling rates. Predator sound playbacks also had consequences for circulating stress hormones, as cortisol levels were significantly elevated in male toadfish exposed to dolphin pops compared with snapping shrimp pops. These findings lend strong support to the hypothesis that individuals of a prey species modulate communication behavior in the presence of a predator, and also suggest that short-term glucocorticoid elevation is associated with anti-predator behavior.

  15. Microwave power transmission system wherein level of transmitted power is controlled by reflections from receiver

    Science.gov (United States)

    Robinson, W. J., Jr. (Inventor)

    1974-01-01

    A microwave, wireless, power transmission system is described in which the transmitted power level is adjusted to correspond with power required at a remote receiving station. Deviations in power load produce an antenna impedance mismatch causing variations in energy reflected by the power receiving antenna employed by the receiving station. The variations in reflected energy are sensed by a receiving antenna at the transmitting station and used to control the output power of a power transmitter.

  16. Environmentally sound energy efficient strategies: A case study of the power section in India

    Energy Technology Data Exchange (ETDEWEB)

    Parikh, J.; Painuly, J.P.; Bhattacharya, K.

    1997-02-01

    Coal is a major source of energy in India, providing more than 60% of the commercial energy requirements. Coal is also most polluting fuel in terms of GHG emissions. Considering India`s energy resources, coal may continue to provide a large part of energy requirements in the future too. Coal is mainly used for generating electricity. Therefore, efficient measures for generation, transmission and end use of electricity can help in reducing the environmental pollution, leading to environmentally sound development. The report highlights some such important measures; reduction in auxiliary consumption (i e. the electricity consumed by generating units in the process of generation), reduction in transmission and distribution losses, and application of demand side management (DSM) options for high tension (HT) industries. The study was conducted in two phases. Maharashtra State Electricity Board (MSEB), the largest utility in Maharashtra was chosen for the detailed study in the first phase. For the study of auxiliary consumption, two typical plants of the MSEB were selected. The transmission losses were studied for the MSEB system based on a snap-shot picture of the system. For the DSM part, energy saving potential in HT industries in Maharashtra was explored based on a survey of HT industries. In the second phase of the study, two more plants outside Maharashtra were also studied to get better insight into diverse causes for the different levels of auxiliary consumption and estimate potential savings. All India potential for savings through reduction in auxiliary consumption was also estimated in this phase. (EG) 10 refs.

  17. Resurrecting the Power-law, Intermediate, and Logamediate Inflations in the DBI Scenario with Constant Sound Speed

    Science.gov (United States)

    Amani, Roonak; Rezazadeh, Kazem; Abdolmaleki, Asrin; Karami, Kayoomars

    2018-02-01

    We investigate the power-law, intermediate, and logamediate inflationary models in the framework of DBI non-canonical scalar field with constant sound speed. In the DBI setting, we first represent the power spectrum of both scalar density and tensor gravitational perturbations. Then, we derive different inflationary observables including the scalar spectral index n s , the running of the scalar spectral index {{dn}}s/d{ln}k, and the tensor-to-scalar ratio r. We show that the 95% CL constraint of the Planck 2015 T + E data on the non-Gaussianity parameter {f}{NL}{DBI} leads to the sound speed bound {c}s≥slant 0.087 in the DBI inflation. Moreover, our results imply that, although the predictions of the power-law, intermediate, and logamediate inflations in the standard canonical framework (c s = 1) are not consistent with the Planck 2015 data, in the DBI scenario with constant sound speed {c}srunning of the scalar spectral index and find that it is compatible with the 95% CL constraint from the Planck 2015 TT,TE,EE+lowP data.

  18. Monitoring Sound Levels and Soundscape Quality in the Living Rooms of Nursing Homes: A Case Study in Flanders (Belgium

    Directory of Open Access Journals (Sweden)

    Francesco Aletta

    2017-08-01

    Full Text Available Recently there has been an increasing interest in the acoustic environment and its perceptual counterpart (i.e., the soundscape of care facilities and their potential to affect the experience of residents with dementia. There is evidence that too loud sounds or poor soundscape quality more generally can affect negatively the quality of life of people with dementia and increase agitation. The AcustiCare project aims to use the soundscape approach to enhance the Quality of Life (QoL of residents and to reduce Behavioral and Psychological Symptoms of Dementia (BPSD, as well as improving the everyday experience of nursing homes for both residents and staff members. In order to gain further insights into the sound environments of such facilities, sound level monitoring and soundscape data collection campaigns were conducted in the living rooms of five nursing homes in Flanders. Results showed that sound levels (dB and loudness levels (sone did not vary significantly between days of the week, but they did so between moments of the day and between living rooms. From the perceptual point of view, several soundscape attributes and the perceived prominence of different sound source types varied significantly between the living rooms investigated, and a positive correlation was found between sound levels and the number of persons present in the living rooms. These findings claim for further attention on the potential role of the sound domain in nursing homes, which should promote (and not only permit better living and working conditions for residents and staff members of nursing homes.

  19. Offshore exposure experiments on cuttlefish indicate received sound pressure and particle motion levels associated with acoustic trauma

    Science.gov (United States)

    Solé, Marta; Sigray, Peter; Lenoir, Marc; van der Schaar, Mike; Lalander, Emilia; André, Michel

    2017-04-01

    Recent findings on cephalopods in laboratory conditions showed that exposure to artificial noise had a direct consequence on the statocyst, sensory organs, which are responsible for their equilibrium and movements in the water column. The question remained about the contribution of the consequent near-field particle motion influence from the tank walls, to the triggering of the trauma. Offshore noise controlled exposure experiments (CEE) on common cuttlefish (Sepia officinalis), were conducted at three different depths and distances from the source and particle motion and sound pressure measurements were performed at each location. Scanning electron microscopy (SEM) revealed injuries in statocysts, which severity was quantified and found to be proportional to the distance to the transducer. These findings are the first evidence of cephalopods sensitivity to anthropogenic noise sources in their natural habitat. From the measured received power spectrum of the sweep, it was possible to determine that the animals were exposed at levels ranging from 139 to 142 dB re 1 μPa2 and from 139 to 141 dB re 1 μPa2, at 1/3 octave bands centred at 315 Hz and 400 Hz, respectively. These results could therefore be considered a coherent threshold estimation of noise levels that can trigger acoustic trauma in cephalopods.

  20. Contralateral routing of signals disrupts monaural level and spectral cues to sound localisation on the horizontal plane.

    Science.gov (United States)

    Pedley, Adam J; Kitterick, Pádraig T

    2017-09-01

    Contra-lateral routing of signals (CROS) devices re-route sound between the deaf and hearing ears of unilaterally-deaf individuals. This rerouting would be expected to disrupt access to monaural level cues that can support monaural localisation in the horizontal plane. However, such a detrimental effect has not been confirmed by clinical studies of CROS use. The present study aimed to exercise strict experimental control over the availability of monaural cues to localisation in the horizontal plane and the fitting of the CROS device to assess whether signal routing can impair the ability to locate sources of sound and, if so, whether CROS selectively disrupts monaural level or spectral cues to horizontal location, or both. Unilateral deafness and CROS device use were simulated in twelve normal hearing participants. Monaural recordings of broadband white noise presented from three spatial locations (-60°, 0°, and +60°) were made in the ear canal of a model listener using a probe microphone with and without a CROS device. The recordings were presented to participants via an insert earphone placed in their right ear. The recordings were processed to disrupt either monaural level or spectral cues to horizontal sound location by roving presentation level or the energy across adjacent frequency bands, respectively. Localisation ability was assessed using a three-alternative forced-choice spatial discrimination task. Participants localised above chance levels in all conditions. Spatial discrimination accuracy was poorer when participants only had access to monaural spectral cues compared to when monaural level cues were available. CROS use impaired localisation significantly regardless of whether level or spectral cues were available. For both cues, signal re-routing had a detrimental effect on the ability to localise sounds originating from the side of the deaf ear (-60°). CROS use also impaired the ability to use level cues to localise sounds originating from

  1. Pilot study of patron sound level exposure in loud restaurants, bars, and clubs in New York city.

    Science.gov (United States)

    Spira-Cohen, Ariel; Caffarelli, Anna; Fung, Lawrence

    2017-07-01

    Visiting restaurants, bars, clubs, and lounges is a regular part of urban cultural life for residents and tourists alike; however, anecdotal reports and diner surveys suggest that sound levels are excessive and diners dislike them. High sound levels in these venues can contribute to both patron and employee overexposure, and young people may be particularly at risk. To supplement the paucity of literature and data on noise in urban venues, patron noise exposure was measured inside a sample of loud New York City restaurants, bars, clubs, and lounges. Sound level measurements were obtained in 59 venues. Field staff conducted one 20-162 minute visit per venue on a Thursday, Friday, or Saturday evening. The equivalent continuous sound pressure level on the A-scale (L Aeq ) was calculated for each visit. Median and mean L Aeq among all venues sampled were both 92 decibels (dBA). Clubs and lounges had a higher mean L Aeq than restaurants and bars (97 vs. 91 dBA, p < 0.05). A greater number of patrons was associated with a higher L Aeq . Higher L Aeq values were observed during later hours of the evening (9 PM and later). For 80% (N = 47) of the venues, the L Aeq was above 85 dBA. In 49% (N = 29) of the venues, the visit exceeded the maximum allowable daily noise dose based on National Institute of Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL) of 85 dBA 8-hr Time-Weighted Average (TWA). Venues should assess indoor sound levels including employee exposure and aim to maintain sound levels that are within NIOSH guidelines.

  2. Ontario's new sound guidelines and wind energy

    International Nuclear Information System (INIS)

    Feilders, J.

    2005-01-01

    Sound and vibration are considered to be pollutants. This paper provides an outline of sound guidelines and their relationship to wind energy and Ontario's Environmental Protection Act, which prohibits the discharge of noises that cause or are likely to cause adverse effects. Certificates of approval are needed for wind turbine generators. The approval process is detailed in this paper, referring to existing limits in urban and rural areas, with sound level limits being based on the source producing the same sound level as background ambient sound levels. Background sound levels included traffic and nature as well as wind. For wind turbines, the ambient is related to the wind induced level by adding 7 decibels to the wind induced background sound level in exposed areas. Points of reception are considered to be locations outdoors where a person may be exposed to the sound or the plane of an exterior door or window of a room in which a person may be exposed to the sound, where the door or window is open. Sound limits apply within a distance of 30 m from a dwelling or camping area in a rural area, with the exception being dwellings on the premises of the wind energy facility. Certificate of Approval report requirements are also necessary and must include test results of turbines proposed in terms of sound power at the operating speeds to be used, as well as calculations of sound levels at points of reception, using an ISO 9613 sound propagation model. It is stated that there are no requirements to conduct an acoustic audit after the wind farm is in operation, should no complaints arise. Noise waivers are not supported by the Ontario Ministry of Energy. However, it was noted that the wind power industry are free to pursue this matter on a political level. tabs., figs

  3. Pressure sound level measurements at an educational environment in Goiânia, Goiás, Brazil

    Science.gov (United States)

    Costa, J. J. L.; do Nascimento, E. O.; de Oliveira, L. N.; Caldas, L. V. E.

    2018-03-01

    In this work, 25 points located on the ground floor of the Federal Institute of Education, Science and Technology of Goias - IFG - Campus Goiânia, were analyzed in morning periods of two Saturdays. The pressure sound levels were measured at internal and external environments during routine activities seeking to perform an environmental monitoring at this institution. The initial hypothesis was that an amusement park (Mutirama Park) was responsible for originating noise pollution in the institute, but the results showed, within the campus environment, sound pressure levels in accordance with the Municipal legislation of Goiânia for all points.

  4. Power Analysis in Two-Level Unbalanced Designs

    Science.gov (United States)

    Konstantopoulos, Spyros

    2010-01-01

    Previous work on statistical power has discussed mainly single-level designs or 2-level balanced designs with random effects. Although balanced experiments are common, in practice balance cannot always be achieved. Work on class size is one example of unbalanced designs. This study provides methods for power analysis in 2-level unbalanced designs…

  5. Sound levels, hearing habits and hazards of using portable cassete players

    Science.gov (United States)

    Hellström, P.-A.; Axelsson, A.

    1988-12-01

    The maximum output sound pressure level ( SPL) from different types of portable cassette players (PCP's) and different headphones was analyzed by using KEMAR in one-third octave bands. The equivalent free-field dB(A) level (EqA-FFSL) was computed from the one-third octave bands corrected by the free-field to the eardrum transfer function. The dB(A) level varied between 104 dB from a low-cost PCP with supra-aural headphones (earphones with headbands and foam pads fitting against the pinna) to 126 dB from a high quality PCP with semi-aural headphones (small earphones without headbands to be used in the concha of the external ear). The cassette tapes used in this study were recorded with music, white noise, narrowband noise and pure tones. The equivalent and maximum SPL was measured in the ear canal (1 mm from eardrum) with the use of mini-microphones in 15 young subjects listening to pop music from PCP's at the highest level they considered comfortable. These SPL measurements corresponded to 112 dB(A) in free field. In a temporary threshold shift ( TTS) study, ten teenagers—four girls and six boys—listened to pop music for 1 h with PCP's at a level they enjoyed. The mean TTS value was 5-10 dB for frequencies between 1 and 8 kHz. In one subject the maximum TTS was 35 dB at 5-6 dB kHz. In order to acquire information about listening habits among youngsters using PCP's, 154 seventh and eighth graders (age 14-15) were interviewed. They used PCP's much less than expected during most of the year, but an increase was reported during the summer holidays.

  6. Impact of missing sounding reports on mandatory levels and tropopause statistics: a case study

    Directory of Open Access Journals (Sweden)

    J. C. Antuña

    2006-10-01

    Full Text Available This paper describes the effect of missing sounding reports on temperature and pressure mean values for mandatory levels using the aerological information from the Camagüey Meteorological Centre. Also it is described the effect of missing data on mean temperature and pressure values at the multiple tropopause levels. The case study belongs to one station for a time lag of eight years. Up to the present these types of studies have been conducted using simulated datasets. The present one uses a real inhomogeneous radiosonde dataset. The main reason for missing reports were transmission problems and possible encoding-decoding difficulties. It has been found that profiles of the mean temperature and altitude show little differences between the complete and incomplete datasets. Moreover, no statistical significant differences were found for the mean values of the variables for the complete and incomplete datasets. The most probable reason for those results is that the cause of the missing reports has a random behaviour. Finally we have found that the only two effects noticed on the statistics were slightly higher values of the mean temperatures in the complete dataset and the decrease in the percent of multiple tropopause reports for the incomplete dataset.

  7. A Measure Based on Beamforming Power for Evaluation of Sound Field Reproduction Performance

    DEFF Research Database (Denmark)

    Chang, Ji-ho; Jeong, Cheol-Ho

    2017-01-01

    This paper proposes a measure to evaluate sound field reproduction systems with an array of loudspeakers. The spatially-averaged squared error of the sound pressure between the desired and the reproduced field, namely the spatial error, has been widely used, which has considerable problems in two...... conditions. First, in non-anechoic conditions, room reflections substantially deteriorate the spatial error, although these room reflections affect human localization to a lesser degree. Second, for 2.5-dimensional reproduction of spherical waves, the spatial error increases consistently due...

  8. Encoding of speech sounds at auditory brainstem level in good and poor hearing aid performers.

    Science.gov (United States)

    Shetty, Hemanth Narayan; Puttabasappa, Manjula

    Hearing aids are prescribed to alleviate loss of audibility. It has been reported that about 31% of hearing aid users reject their own hearing aid because of annoyance towards background noise. The reason for dissatisfaction can be located anywhere from the hearing aid microphone till the integrity of neurons along the auditory pathway. To measure spectra from the output of hearing aid at the ear canal level and frequency following response recorded at the auditory brainstem from individuals with hearing impairment. A total of sixty participants having moderate sensorineural hearing impairment with age range from 15 to 65 years were involved. Each participant was classified as either Good or Poor Hearing aid Performers based on acceptable noise level measure. Stimuli /da/ and /si/ were presented through loudspeaker at 65dB SPL. At the ear canal, the spectra were measured in the unaided and aided conditions. At auditory brainstem, frequency following response were recorded to the same stimuli from the participants. Spectrum measured in each condition at ear canal was same in good hearing aid performers and poor hearing aid performers. At brainstem level, better F 0 encoding; F 0 and F 1 energies were significantly higher in good hearing aid performers than in poor hearing aid performers. Though the hearing aid spectra were almost same between good hearing aid performers and poor hearing aid performers, subtle physiological variations exist at the auditory brainstem. The result of the present study suggests that neural encoding of speech sound at the brainstem level might be mediated distinctly in good hearing aid performers from that of poor hearing aid performers. Thus, it can be inferred that subtle physiological changes are evident at the auditory brainstem in a person who is willing to accept noise from those who are not willing to accept noise. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier

  9. Noise and noise disturbances from wind power plants - Tests with interactive control of sound parameters for more comfortable and less perceptible sounds; Buller och bullerstoerningar fraan vindkraftverk - Foersoek med interaktiv styrning av ljudparametrar foer behagligare och mindre maerkbara ljud

    Energy Technology Data Exchange (ETDEWEB)

    Persson-Waye, K.; Oehrstroem, E.; Bjoerkman, M.; Agge, A. [Goeteborg Univ. (Sweden). Dept. of Environmental Medicine

    2001-12-01

    In experimental pilot studies, a methodology has been worked out for interactively varying sound parameters in wind power plants. In the tests, 24 persons varied the center frequency of different band-widths, the frequency of a sinus-tone and the amplitude-modulation of a sinus-tone in order to create as comfortable a sound as possible. The variations build on the noise from the two wind turbines Bonus and Wind World. The variations were performed with a constant dba level. The results showed that the majority preferred a low-frequency tone (94 Hz and 115 Hz for Wind World and Bonus, respectively). The mean of the most comfortable amplitude-modulation varied between 18 and 22 Hz, depending on the ground frequency. The mean of the center-frequency for the different band-widths varied from 785 to 1104 Hz. In order to study the influence of the wind velocity on the acoustic character of the noise, a long-time measurement program has been performed. A remotely controlled system has been developed, where wind velocity, wind direction, temperature and humidity are registered simultaneously with the noise. Long-time registrations have been performed for four different wing turbines.

  10. Reactive Power Impact on Lifetime Prediction of Two-level Wind Power Converter

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede; Lau, M.

    2013-01-01

    The influence of reactive power injection on the dominating two-level wind power converter is investigated and compared in terms of power loss and thermal behavior. Then the lifetime of both the partial-scale and full-scale power converter is estimated based on the widely used Coffin-Manson model...

  11. Measuring sound absorption: considerations on the measurement of the active acoustic power

    NARCIS (Netherlands)

    Kuipers, E.R.; Wijnant, Ysbrand H.; de Boer, Andries

    2014-01-01

    Using a local plane wave assumption, one can determine the normal incidence sound absorption coefficient of a surface by measuring the acoustic pressure and the particle velocity normal to that surface. As the measurement surface lies in front of the material surface, the measured active and

  12. First- and Second-level Bayesian Inference of Flow Resistivity of Sound Absorber and Room’s Influence

    DEFF Research Database (Denmark)

    Choi, Sang-Hyeon; Lee, Ikjin; Jeong, Cheol-Ho

    2016-01-01

    Sabine absorption coefficient is a widely used one deduced from reverberation time measurements via the Sabine equation. First- and second-level Bayesian analysis are used to estimate the flow resistivity of a sound absorber and the influences of the test chambers from Sabine absorption...

  13. High levels of sound pressure: acoustic reflex thresholds and auditory complaints of workers with noise exposure

    Directory of Open Access Journals (Sweden)

    Alexandre Scalli Mathias Duarte

    2015-08-01

    Full Text Available INTRODUCTION: The clinical evaluation of subjects with occupational noise exposure has been difficult due to the discrepancy between auditory complaints and auditory test results. This study aimed to evaluate the contralateral acoustic reflex thresholds of workers exposed to high levels of noise, and to compare these results to the subjects' auditory complaints.METHODS: This clinical retrospective study evaluated 364 workers between 1998 and 2005; their contralateral acoustic reflexes were compared to auditory complaints, age, and noise exposure time by chi-squared, Fisher's, and Spearman's tests.RESULTS: The workers' age ranged from 18 to 50 years (mean = 39.6, and noise exposure time from one to 38 years (mean = 17.3. We found that 15.1% (55 of the workers had bilateral hearing loss, 38.5% (140 had bilateral tinnitus, 52.8% (192 had abnormal sensitivity to loud sounds, and 47.2% (172 had speech recognition impairment. The variables hearing loss, speech recognition impairment, tinnitus, age group, and noise exposure time did not show relationship with acoustic reflex thresholds; however, all complaints demonstrated a statistically significant relationship with Metz recruitment at 3000 and 4000 Hz bilaterally.CONCLUSION: There was no significance relationship between auditory complaints and acoustic reflexes.

  14. Multichannel loudness compensation method based on segmented sound pressure level for digital hearing aids

    Science.gov (United States)

    Liang, Ruiyu; Xi, Ji; Bao, Yongqiang

    2017-07-01

    To improve the performance of gain compensation based on three-segment sound pressure level (SPL) in hearing aids, an improved multichannel loudness compensation method based on eight-segment SPL was proposed. Firstly, the uniform cosine modulated filter bank was designed. Then, the adjacent channels which have low or gradual slopes were adaptively merged to obtain the corresponding non-uniform cosine modulated filter according to the audiogram of hearing impaired persons. Secondly, the input speech was decomposed into sub-band signals and the SPL of every sub-band signal was computed. Meanwhile, the audible SPL range from 0 dB SPL to 120 dB SPL was equally divided into eight segments. Based on these segments, a different prescription formula was designed to compute more detailed gain to compensate according to the audiogram and the computed SPL. Finally, the enhanced signal was synthesized. Objective experiments showed the decomposed signals after cosine modulated filter bank have little distortion. Objective experiments showed that the hearing aids speech perception index (HASPI) and hearing aids speech quality index (HASQI) increased 0.083 and 0.082 on average, respectively. Subjective experiments showed the proposed algorithm can effectively improve the speech recognition of six hearing impaired persons.

  15. The Power of Cross-Level Partnerships.

    Science.gov (United States)

    Youngerman, Stephanie

    1998-01-01

    Much credit for the tangible feeling of caring at an Idaho elementary school is due to partnerships that faculty, families, and students have forged across grade levels. These cross-grade buddy systems have put the brakes on bullies, fostered student friendships, and resolved personality conflicts among staff members. (MLH)

  16. University students' understanding level about words related to nuclear power

    International Nuclear Information System (INIS)

    Oiso, Shinichi; Watabe, Motoki

    2012-01-01

    The authors conducted a survey of university students' understanding level about words related to nuclear power before and after Fukushima Daiichi Power Plant accident, and analyzed the difference between before and after the accident. The results show that university students' understanding level improved after the accident, especially in the case of reported words by mass media. Understanding level of some nuclear power security words which were not reported so much by mass media also improved. That may be caused by rising of people's concern about nuclear power generation after the accident, and there is a possibility that the accident motivated people to access such words via internet, journals, etc. (author)

  17. Analysis of superconducting microstrip resonator at various microwave power levels

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, G.P.; Jacob, M.V.; Jayakumar, M.; Bhatnagar, P.K. [Department of Electronic Science, University of Delhi, South Campus, Benito Juarez Road, New Delhi 110021 (India); Kataria, N.D. [National Physical Laboratory, K. S. Krishnan Road, New Delhi 110 012 (India)

    1997-05-01

    The real and imaginary parts of the surface impedance of YBCO superconductors have been studied at different microwave power levels. Using the relations for the critical current density and the grain boundary resistance, a relation for calculating the power dependence of the surface resistance has been obtained. Also, a relation to find the resonant frequency of a superconducting microstrip resonator at various input power levels has been derived. Measurements have been carried out on various microstrip resonators to study the variation of surface resistance and resonant frequency at different rf power levels. The experimental results are in good agreement with theoretical results. {copyright} {ital 1997 American Institute of Physics.}

  18. Exterior sound level measurements of over-snow vehicles at Yellowstone National Park.

    Science.gov (United States)

    2008-09-30

    Sounds associated with oversnow vehicles, such as snowmobiles and snowcoaches, are an : important management concern at Yellowstone and Grand Teton National Parks. The John A. : Volpe National Transportation Systems Centers Environmental Measureme...

  19. Challenges with Tertiary-Level Mechatronic Fluid Power

    DEFF Research Database (Denmark)

    Dransfield, Peter; Conrad, Finn

    1996-01-01

    As authors we take the view that mechatronics, as it relates to fluid power, has three levels which we designate as primary, secondary and tertiary. A brief review of the current status of fluid power, hydraulic and pneumatic, and of electronic control of it is presented and discussed. The focus...... is then on tertiary-level mechatronic fluid power and the challenges to it being applied successfully....

  20. Experimental investigation of the temperature dependence of sound velocity in the structural materials for nuclear power engineering

    International Nuclear Information System (INIS)

    Roshchupkin, V.V.; Pokrasin, M.A.; Chernov, A.I.; Semashko, N.A.; Filonenko, S.F.

    1999-01-01

    The purpose of the study consists in determination of the sound velocity temperature dependence in structural materials for nuclear power engineering. In particular, the Zr-2.5%Nb, Hastelloys-H alloys and X2.5M steel are studied. The facility for studying acoustic parameters of metals and alloys is described. The software makes it possible to obtain the results in various forms with the data stored in the memory for further analysis. The data on the above alloys obtained by use of various methods are presented and analyzed [ru

  1. Experimental Study of a Multi Level Overtopping Wave Power Device

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Hald, Tue; Frigaard, Peter Bak

    2002-01-01

    Results of experimental investigations of a floating wave energy device called Power Pyramid is presented. The Power Pyramid utilizes reservoirs in multiple levels when capturing wave overtopping and converting it into electrical energy. The effect of capturing the overtopping in multiple levels......, compared to only one level, has been evaluated experimentally. From the experimental results, and the performed optimizations based on these, it has been found that the efficiency of a wave power device of the overtopping type can be increased by as much as 76 % by using 5 levels instead of 1. However...

  2. Three integrated photovoltaic/sound barrier power plants. Construction and operational experience

    International Nuclear Information System (INIS)

    Nordmann, T.; Froelich, A.; Clavadetscher, L.

    2002-01-01

    After an international ideas competition by TNC Switzerland and Germany in 1996, six companies where given the opportunity to construct a prototype of their newly developed integrated PV-sound barrier concepts. The main goal was to develop highly integrated concepts, allowing the reduction of PV sound barrier systems costs, as well as the demonstration of specific concepts for different noise situations. This project is strongly correlated with a German project. Three of the concepts of the competition are demonstrated along a highway near Munich, constructed in 1997. The three Swiss installations had to be constructed at different locations, reflecting three typical situations for sound barriers. The first Swiss installation was the world first Bi-facial PV-sound barrier. It was built on a highway bridge at Wallisellen-Aubrugg in 1997. The operational experience of the installation is positive. But due to the different efficiencies of the two cell sides, its specific yield lies somewhat behind a conventional PV installation. The second Swiss plant was finished in autumn 1998. The 'zig-zag' construction is situated along the railway line at Wallisellen in a densely inhabited area with some local shadowing. Its performance and its specific yield is comparatively low due to a combination of several reasons (geometry of the concept, inverter, high module temperature, local shadows). The third installation was constructed along the motor way A1 at Bruettisellen in 1999. Its vertical panels are equipped with amorphous modules. The report show, that the performance of the system is reasonable, but the mechanical construction has to be improved. A small trial field with cells directly laminated onto the steel panel, also installed at Bruettisellen, could be the key development for this concept. This final report includes the evaluation and comparison of the monitored data in the past 24 months of operation. (author)

  3. A Mixed-Methods Trial of Broad Band Noise and Nature Sounds for Tinnitus Therapy: Group and Individual Responses Modeled under the Adaptation Level Theory of Tinnitus

    Science.gov (United States)

    Durai, Mithila; Searchfield, Grant D.

    2017-01-01

    Objectives: A randomized cross-over trial in 18 participants tested the hypothesis that nature sounds, with unpredictable temporal characteristics and high valence would yield greater improvement in tinnitus than constant, emotionally neutral broadband noise. Study Design: The primary outcome measure was the Tinnitus Functional Index (TFI). Secondary measures were: loudness and annoyance ratings, loudness level matches, minimum masking levels, positive and negative emotionality, attention reaction and discrimination time, anxiety, depression and stress. Each sound was administered using MP3 players with earbuds for 8 continuous weeks, with a 3 week wash-out period before crossing over to the other treatment sound. Measurements were undertaken for each arm at sound fitting, 4 and 8 weeks after administration. Qualitative interviews were conducted at each of these appointments. Results: From a baseline TFI score of 41.3, sound therapy resulted in TFI scores at 8 weeks of 35.6; broadband noise resulted in significantly greater reduction (8.2 points) after 8 weeks of sound therapy use than nature sounds (3.2 points). The positive effect of sound on tinnitus was supported by secondary outcome measures of tinnitus, emotion, attention, and psychological state, but not interviews. Tinnitus loudness level match was higher for BBN at 8 weeks; while there was little change in loudness level matches for nature sounds. There was no change in minimum masking levels following sound therapy administration. Self-reported preference for one sound over another did not correlate with changes in tinnitus. Conclusions: Modeled under an adaptation level theory framework of tinnitus perception, the results indicate that the introduction of broadband noise shifts internal adaptation level weighting away from the tinnitus signal, reducing tinnitus magnitude. Nature sounds may modify the affective components of tinnitus via a secondary, residual pathway, but this appears to be less important

  4. Noise exposure in movie theaters: a preliminary study of sound levels during the showing of 25 films.

    Science.gov (United States)

    Warszawa, Anna; Sataloff, Robert T

    2010-09-01

    The harmful effects of noise exposure during leisure-time activities are beginning to receive some scrutiny. We conducted a preliminary study to investigate the noise levels during the showings of 25 different films. During each screening, various sound measurements were made with a dosimeter. The movies were classified on the basis of both their Motion Picture Association of America (MPAA) rating and their genre, and the size of the theater and the size of the audience were taken into consideration in the final analysis. Our findings suggest that the sound levels of many movies might be harmful to hearing, although we can draw no definitive conclusions. We did not discern any relationship between noise levels and either MPAA rating or genre. Further studies are recommended.

  5. Effect of abdominal vibroacoustic stimulation on sound and acceleration levels at the head of the fetal sheep.

    Science.gov (United States)

    Abrams, R M; Peters, A J; Gerhardt, K J

    1997-08-01

    To measure the vibratory response of the fetal head and abdominal wall in sheep during vibroacoustic stimulation. A piezoresistive accelerometer was attached to the skulls of seven sheep fetuses (128-134 days' gestational age), and a miniature hydrophone was attached to the skin overlying the fetal temporal bone. During fetal preparation and vibroacoustic stimulation procedures, ewes were anesthetized and supine. Vibroacoustic stimulation of the maternal abdomen was produced by each of two clinical devices that differed in spectral content, and an electric toothbrush. The approximate fundamental frequencies (f0) and first overtones (f1), as determined by both recordings of intrauterine sound pressure level and fetal head acceleration, were as follows: fetal acoustic stimulator, 75 and 150 Hz; electronic larynx, 150 and 300 Hz; and electric toothbrush, 25 and 50 Hz, respectively. At fundamental frequencies and first overtones, the ranges of fetal head accelerations (expressed in 1/12-octave bands) were as follows: fetal acoustic stimulator, 10-53 and 25-224 mm/sec2; electronic larynx, 10-53 and 18-114 mm/sec2; and electric toothbrush, 33-792 and 8-116 mm/sec2, respectively. Sound pressure levels exceeded 110 dB in all cases. High sound pressure levels in the uterus were proportional to fetal head vibration levels. Vibroacoustic stimulation of the surface of the abdomen of pregnant sheep is accompanied by both acoustic and vibratory exposure of the fetus.

  6. The effect of interaural-level-difference fluctuations on the externalization of sound

    DEFF Research Database (Denmark)

    Catic, Jasmina; Santurette, Sébastien; Buchholz, Jörg M.

    2013-01-01

    Real-world sound sources are usually perceived as externalized and thus properly localized in both direction and distance. This is largely due to (1) the acoustic filtering by the head, torso, and pinna, resulting in modifications of the signal spectrum and thereby a frequency-dependent shaping o...... with the analysis of short-term ILDs at different distances showing that a decreased distance to the sound source also reduced the ILD fluctuations. © 2013 Acoustical Society of America.......Real-world sound sources are usually perceived as externalized and thus properly localized in both direction and distance. This is largely due to (1) the acoustic filtering by the head, torso, and pinna, resulting in modifications of the signal spectrum and thereby a frequency-dependent shaping...... in a standard listening room. Next, the effect of ILD fluctuations on the degree of externalization was investigated in a psychoacoustic experiment performed in the same listening room. Individual binaural impulse responses were used to simulate a distant sound source delivered via headphones. The ILDs were...

  7. Effects of Interaural Level and Time Differences on the Externalization of Sound

    DEFF Research Database (Denmark)

    Dau, Torsten; Catic, Jasmina; Santurette, Sébastien

    differences (ILDs) and interaural time differences (ITDs). Further, the binaural cues provided by reverberation in an enclosed space may also contribute to externalization. While these spatial cues are available in their natural form when listening to real-world sound sources, hearing-aid signal processing...

  8. Hearing performance with 2 different high-power sound processors for osseointegrated auditory implants.

    Science.gov (United States)

    Kurz, Anja; Caversaccio, Marco; Kompis, Martin

    2013-06-01

    To compare speech understanding of the BAHA BP110 and BAHA Intenso sound processors. Prospective experimental study. Tertiary referral center. Twenty experienced user of osseointegrated auditory implants with conductive or mixed hearing loss. In a first session, half of the participants were fitted with an Intenso, the other half with a BP110. After 1 month of use, aided speech understanding in quiet and in noise was measured, and the other test processor was fitted. One month later, speech understanding with the second sound processor was assessed. Speech understanding in quiet and in noise, with noise arriving either from the front, the rear, or the side of the user with the osseointegrated bone conductor. Significant improvements were found for both processors for speech understanding in quiet (+9.6 to +34.8 percent points; p = 0.02 to 0.001) and in noise (+6.2 to +13.8 dB, p processors in quiet. In noise, speech understanding is significantly better with the BP110 when compared to the Intenso for noise from the rear.

  9. Investigation of the Sound Pressure Level (SPL) of earphones during music listening with the use of physical ear canal models

    Science.gov (United States)

    Aying, K. P.; Otadoy, R. E.; Violanda, R.

    2015-06-01

    This study investigates on the sound pressure level (SPL) of insert-type earphones that are commonly used for music listening of the general populace. Measurements of SPL from earphones of different respondents were measured by plugging the earphone to a physical ear canal model. Durations of the earphone used for music listening were also gathered through short interviews. Results show that 21% of the respondents exceed the standard loudness/duration relation recommended by the World Health Organization (WHO).

  10. Sound Hole Sound

    OpenAIRE

    Politzer, David

    2015-01-01

    The volume of air that goes in and out of a musical instrument's sound hole is related to the sound hole's contribution to the volume of the sound. Helmholtz's result for the simplest case of steady flow through an elliptical hole is reviewed. Measurements on multiple holes in sound box geometries and scales relevant to real musical instruments demonstrate the importance of a variety of effects. Electric capacitance of single flat plates is a mathematically identical problem, offering an alte...

  11. Power Constrained High-Level Synthesis of Battery Powered Digital Systems

    DEFF Research Database (Denmark)

    Nielsen, Sune Fallgaard; Madsen, Jan

    2003-01-01

    We present a high-level synthesis algorithm solving the combined scheduling, allocation and binding problem minimizing area under both latency and maximum power per clock-cycle constraints. Our approach eliminates the large power spikes, resulting in an increased battery lifetime, a property...... of utmost importance for battery powered embedded systems. Our approach extends the partial-clique partitioning algorithm by introducing power awareness through a heuristic algorithm which bounds the design space to those of power feasible schedules. We have applied our algorithm on a set of dataflow graphs...

  12. POWER LEVEL EFFECT IN A PWR ROD EJECTION ACCIDENT

    International Nuclear Information System (INIS)

    Diamond, D.J.; Bromley, B.P.; Aronson, A.L.

    2002-01-01

    The purpose of this study is to determine the effect of the initial power level during a rod ejection accident (REA) on the ejected rod worth and the resulting energy deposition in the fuel. The model used is for the hot zero power (HZP) conditions at the end of a typical fuel cycle for the Three Mile Island Unit 1 pressurized water reactor. PARCS , a transient, three-dimensional, two-group neutron nodal diffusion code, coupled with its own thermal-hydraulics model, is used to perform both steady-state and transient simulations. The worth of an ejected control rod is affected by both power level, and the positions of control banks. As the power level is increased, the worth of a single central control rod tends to drop due to thermal-hydraulic feedback and control bank removal, both of which flatten the radial neutron flux and power distributions. Although the peak fuel pellet enthalpy rise during an REA will be greater for a given ejected rod worth at elevated initial power levels, it is more likely the HZP condition will cause a greater net energy deposition because an ejected rod will have the highest worth at HZP. Thus, the HZP condition can be considered the most conservative in a safety evaluation

  13. Investigation of Energy Consumption and Sound Quality for Class-D Audio Amplifiers using Tracking Power Supplies

    DEFF Research Database (Denmark)

    Yamauchi, Akira; Schneider, Henrik; Knott, Arnold

    2015-01-01

    and a concern in other applications where multiple amplifier channels are generating heat problems. It is found that power losses at low power levels account for close to 78 % of the energy consumption based on typical consumer behavior investigations. This paper investigates the theoretical limits of stepless...... power supply tracking and its influence on power losses, audio performance and environmental impact for a 130 W class-D amplifier prototype as well as a commercialized class-D amplifier. Both modeled and experimental results verify that a large improvement of efficiency can be achieved. The total...

  14. Using Sound to Modify Fish Behavior at Power-Production and Water-Control Facilities: A Workshop December 12-13, 1995. Phase II: Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Thomas J. [ed.] [Pacific Northwest National Lab., Richland, WA (United States); Popper, Arthur N. [ed.] [Univ. of Maryland, College Park, MD (United States)

    1997-06-01

    A workshop on ``Use of Sound for Fish Protection at Power-Production and Water-Control Facilities`` was held in Portland, Oregon on December 12--13, 1995. This workshop convened a 22-member panel of international experts from universities, industry, and government to share knowledge, questions, and ideas about using sound for fish guidance. Discussions involved in a broad range of indigenous migratory and resident fish species and fish-protection issues in river systems, with particular focus on the Columbia River Basin. Because the use of sound behavioral barriers for fish is very much in its infancy, the workshop was designed to address the many questions being asked by fishery managers and researchers about the feasibility and potential benefits of using sound to augment physical barriers for fish protection in the Columbia River system.

  15. Using sound to modify fish behavior at power-production and water-control facilities: A workshop. Phase 2: Final report

    International Nuclear Information System (INIS)

    Carlson, T.J.; Popper, A.N.

    1997-06-01

    A workshop on ''''Use of Sound for Fish Protection at Power-Production and Water-Control Facilities'''' was held in Portland, Oregon on December 12--13, 1995. This workshop convened a 22-member panel of international experts from universities, industry, and government to share knowledge, questions, and ideas about using sound for fish guidance. Discussions involved in a broad range of indigenous migratory and resident fish species and fish-protection issues in river systems, with particular focus on the Columbia River Basin. Because the use of sound behavioral barriers for fish is very much in its infancy, the workshop was designed to address the many questions being asked by fishery managers and researchers about the feasibility and potential benefits of using sound to augment physical barriers for fish protection in the Columbia River system

  16. Broadcast sound technology

    CERN Document Server

    Talbot-Smith, Michael

    1990-01-01

    Broadcast Sound Technology provides an explanation of the underlying principles of modern audio technology. Organized into 21 chapters, the book first describes the basic sound; behavior of sound waves; aspects of hearing, harming, and charming the ear; room acoustics; reverberation; microphones; phantom power; loudspeakers; basic stereo; and monitoring of audio signal. Subsequent chapters explore the processing of audio signal, sockets, sound desks, and digital audio. Analogue and digital tape recording and reproduction, as well as noise reduction, are also explained.

  17. The role of communications in achieving sound energy policy and excellence in nuclear power

    International Nuclear Information System (INIS)

    Harris, B.

    1988-01-01

    This paper highlights the renewed emphasis on excellence throughout the U.S. nuclear power industry. The author discusses the role of the industry's national communications programs in helping achieve excellence, and in helping maintain the viability of nuclear power as a major source of energy in America. The author discusses an industry report which emphasized that quality operational performance of all U.S. nuclear utilities is absolutely essential for public and regulatory trust. To achieve that trust, the public must know about operational excellence. According to the author, delivering that message is one of the industry's major assignments

  18. Magnetostrictive device for high-temperature sound and vibration measurement in nuclear power stations

    International Nuclear Information System (INIS)

    Hans, R.; Podgorski, J.

    1977-01-01

    The demands on the monitoring systems in nuclear power stations are increasing continuously, not only because of more stringent safety requirements but also for reasons of plant availability and thus economic efficiency. The noise and vibration measurements which therefore have to be taken make it necessary to provide measuring devices with a high degree of efficiency, adequate sensitivity and resistance to high temperatures, radiation and corrosion. Probes using the magnetostrictive effect, whereby a ferromagnetic core changes its length in a magnetic field - a phenomenon which has been known for approximately fifty years - fulfill all the conditions for application in nuclear power stations. (orig.) [de

  19. The impact of a noise reduction quality improvement project upon sound levels in the open-unit-design neonatal intensive care unit.

    Science.gov (United States)

    Liu, W F

    2010-07-01

    To decrease measured sound levels in the neonatal intensive care unit through implementation of human factor and minor design modification strategies. Prospective time series. Two open-unit-design neonatal centers. Implementation of a coordinated program of noise reduction strategies did not result in any measurable improvement in levels of loudness or quiet. Two centers, using primarily human behavior noise reduction strategies, were unable to demonstrate measurable improvements in sound levels within the occupied open-unit-design neonatal intensive care unit.

  20. The sound power emitted by a source of low acoustic impedance

    DEFF Research Database (Denmark)

    Jacobsen, Finn; Verholt, Lars M.

    1998-01-01

    Several authors have maintained that a source of low acoustic impedance (which includes standardised reference sources of the aerodynamic type) would radiate less than the free field power in a reverberation room. However, neither computer simulations nor experiments have confirmed this assertion....

  1. Noise induced hearing loss in dance music disc jockeys and an examination of sound levels in nightclubs.

    Science.gov (United States)

    Bray, Adam; Szymański, Marcin; Mills, Robert

    2004-02-01

    Noise exposure, hearing loss and associated otological symptoms have been studied in a group of 23 disc jockeys using a questionnaire and pure tone audiometry. The level of noise exposure in the venues where they work has also been studied using Ametek Mk-3 audio dosimeters. Three members of the study group showed clear evidence of noise-induced hearing loss on audiometry, 70 per cent reported temporary threshold shift after sessions and 74 per cent reported tinnitus. Sound levels of up to 108 dB(A) were recorded in the nightclubs. The average level for a typical session was 96 dB(A) which is above the level at which the provision of ear protection is mandatory for employers in industry. It can be concluded that DJs are at substantial risk of developing noise-induced hearing loss and noise exposure in nightclubs frequently exceeds safe levels.

  2. A critical examination of some of the field indicators that have been proposed in connection with sound power determination using the intensity method

    DEFF Research Database (Denmark)

    Jacobsen, Finn

    1996-01-01

    A considerable number of 'field indicators' or 'quality indicators' have been proposed in connection with sound power determination based on measurement of intensity. For example, the ISO 9614-1 standard prescribes the use four indicators, and in the North American ANSI S12.12 standard no less than...

  3. Development of neutral injection to the megawatt power level

    International Nuclear Information System (INIS)

    Thompson, E.; Coupland, J.R.; Dirmikis, D.; Hammond, D.P.; Holmes, A.J.T.

    1976-01-01

    The various options for the production of energetic neutral beams at the MW power level based on positive ion extraction are discussed. We also consider in more detail the design of beam extraction and acceleration structures along with that of the neutralizer and necessary cryopumping

  4. Sound spectral analysis of snoring sound and site of obstruction in obstructive sleep apnea syndrome.

    Science.gov (United States)

    Xu, Huijie; Huang, Weining; Yu, Lisheng; Chen, Lan

    2010-10-01

    This study demonstrates that there is a significant difference in sound spectrum between first snoring sound after upper level and lower level obstructive apneas, and it is possible to use sound spectrum analysis as a supplementary method to determine the obstructive site of a patient with obstructive sleep apnea syndrome (OSAS). To investigate the difference in sound spectrum between the first snoring sounds after upper level (above the free margin of soft palate) obstructive apneas and lower level (below the free margin of soft palate) obstructive apneas in patients with OSAS. Thirty male patients with OSAS were included in this study. Overnight snoring sound was recorded and continuous upper airway pressure measurement was performed simultaneously on each subject. The first snores after upper level and lower level obstructive apneas were identified and analyzed acoustically. The mean of peak frequencies, central frequencies, and proportions of energy from 800 Hz to 2000 Hz and above 2000 Hz of the first snoring sounds after lower level obstructive apneas were higher and the proportion of energy below 800 Hz was lower than those after upper level obstructive apneas. The differences of all the parameters were of significance. The power spectrum of the two types of snoring sounds also exhibited different characters.

  5. Seismic fragility levels of nuclear power plant equipment

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1987-01-01

    Seismic fragility levels of safety-related electrical and mechanical equipment used in nuclear power plants are discussed. The fragility level is defined as the vibration level corresponding to initiation of equipment malfunctions. The test response spectrum is used as a measure of this vibration level. The fragility phenomenon of an equipment is represented by a number of response spectra corresponding to various failure modes. Analysis methods are described for determination of the fragility level by use of existing test data. Useful conversion factors are tabulated to transform test response spectra from one damping value to another. Results are presented for switch-gears and motor control centers. The capacity levels of these equipment assemblies are observed to be limited by malfunctioning of contactors, motor starters, relays and/or switches. The applicability of the fragility levels, determined in terms of test response spectra, to Seismic Margin Studies and Probabilistic Risk Assessments is discussed and specific recommendations are provided

  6. Design of megawatt power level heat pipe reactors

    Energy Technology Data Exchange (ETDEWEB)

    Mcclure, Patrick Ray [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Poston, David Irvin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dasari, Venkateswara Rao [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reid, Robert Stowers [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-12

    An important niche for nuclear energy is the need for power at remote locations removed from a reliable electrical grid. Nuclear energy has potential applications at strategic defense locations, theaters of battle, remote communities, and emergency locations. With proper safeguards, a 1 to 10-MWe (megawatt electric) mobile reactor system could provide robust, self-contained, and long-term power in any environment. Heat pipe-cooled fast-spectrum nuclear reactors have been identified as a candidate for these applications. Heat pipe reactors, using alkali metal heat pipes, are perfectly suited for mobile applications because their nature is inherently simpler, smaller, and more reliable than “traditional” reactors. The goal of this project was to develop a scalable conceptual design for a compact reactor and to identify scaling issues for compact heat pipe cooled reactors in general. Toward this goal two detailed concepts were developed, the first concept with more conventional materials and a power of about 2 MWe and a the second concept with less conventional materials and a power level of about 5 MWe. A series of more qualitative advanced designs were developed (with less detail) that show power levels can be pushed to approximately 30 MWe.

  7. Noise levels and sound pollution associated with various operative procedures and equipments in a pediatric dental environment-A clinical study.

    Science.gov (United States)

    Goswami, Mousumi; Singh, Darrel; Vashist, Binny; Marwaha, Sugandha

    2017-01-01

    To analyse sound levels and sound pollution in a Pediatric Dental Clinic and to analyse whether the levels are significant to the extent of being a health hazard. Noise levels were measured in a Pediatric dental clinic in an institutional setting with a precision noise level meter ((HTC 1350). Recordings were taken at different times of the day, at the centre, chair-side, reception, play area and four corners of the department keeping the microphone at a distance of 6 in. from the operator's ear. The noise levels of various equipments i.e. suction, micromotor, airotor were measured with the equipments turned on and during cutting operations with the microphone placed at a distance of 6 in. from the sound source. The sound levels for the laboratory equipments were taken at a distance of 6 in. and 2 m. The highest mean sound levels were recorded at the reception, play area and chair-side area with least mean sound levels recorded at 9:00am which increased at 11:30am & 2:00pm and reduced again at 3:30pm The maximum sounds were produced by the lathe trimmer, airotor and scaler. Noise levels in a pediatric clinic approach the level of risk of hearing loss [85 db(A)]. This would have a serious effect on both providers and patients and a concerted effort would be required to control the noise levels and thus avoid the potential health hazards that it poses.

  8. Effects of training on time-varying spectral energy and sound pressure level in nine male classical singers.

    Science.gov (United States)

    Ferguson, Sam; Kenny, Dianna T; Cabrera, Densil

    2010-01-01

    The male classical singing voice is a musical instrument that is very important in western culture. It has many acoustic features which should change and improve over the period in which the singer trains. In this study we compare nine singers in different stages of training, from university level students through to international soloists. Typically, Energy Ratio (ER; a measure of mean spectral slope) and mean sound pressure level (SPL) may be calculated to summarize an entire singing sample. We investigate an alternative approach, by calculating the time-varying ER and SPL. The inspection of the distribution of these descriptors over an aria's time period yields a more detailed picture of the strategies for high-frequency energy production used by singers with different levels of training. Copyright 2010 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  9. Float level switch for a nuclear power plant containment vessel

    Science.gov (United States)

    Powell, J.G.

    1993-11-16

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel. 1 figures.

  10. Evaluation of power commissioning of the Mochovce Unit 1 power level up to 100 % Nnom

    International Nuclear Information System (INIS)

    Sarvaic, I.; Mickolci, M.

    1998-01-01

    The document contains an evaluation of the power phase of power commissioning of the Mochovce Unit 1 in the phase up to the power level of 100 % N nom .In the document, the courses and results of tests in this phase of power commissioning are summarized, evaluation of the performance of important systems and equipment of the unit is carried out, and the compliance with Limits and Conditions in the course of the phase is assessed. On this basis, conclusions are drawn and recommendations for the unit to be ready for subsequent phases of the power commissioning. The evaluation was developed by the scientific management of the Mochovce commissioning providing an independent support for the operators for supervising the commissioning tasks from the point of nuclear safety

  11. Directional sound radiation from substation transformers

    International Nuclear Information System (INIS)

    Maybee, N.

    2009-01-01

    This paper presented the results of a study in which acoustical measurements at two substations were analyzed to investigate the directional behaviour of typical arrays having 2 or 3 transformers. Substation transformers produce a characteristic humming sound that is caused primarily by vibration of the core at twice the frequency of the power supply. The humming noise radiates predominantly from the tank enclosing the core. The main components of the sound are harmonics of 120 Hz. Sound pressure level data were obtained for various directions and distances from the arrays, ranging from 0.5 m to over 100 m. The measured sound pressure levels of the transformer tones displayed substantial positive and negative excursions from the calculated average values for many distances and directions. The results support the concept that the directional effects are associated with constructive and destructive interference of tonal sound waves emanating from different parts of the array. Significant variations in the directional sound pattern can occur in the near field of a single transformer or an array, and the extent of the near field is significantly larger than the scale of the array. Based on typical dimensions for substation sites, the distance to the far field may be much beyond the substation boundary and beyond typical setbacks to the closest dwellings. As such, the directional sound radiation produced by transformer arrays introduces additional uncertainty in the prediction of substation sound levels at dwellings within a few hundred meters of a substation site. 4 refs., 4 figs.

  12. Module-Level Power Converters For Parallel Connected Photovoltaic Arrays

    Science.gov (United States)

    2012-01-01

    NOMENCLATURE Symbol Description PV Photovoltaic MPPT Maximum Power Point Tracking PWM Pulse-Width Modulation ZVS Zero Voltage...tracking ( MPPT ). Good source and load regulation are needed so that individual 2 panels operate near the same voltage, regardless of system voltage...panel to be delivered to the string with the use of module-level MPPT . However, the advantage is not as significant as a parallel-connected array. The

  13. Comparative analysis of performance in reading and writing of children exposed and not exposed to high sound pressure levels.

    Science.gov (United States)

    Santos, Juliana Feitosa dos; Souza, Ana Paula Ramos de; Seligman, Lilian

    2013-01-01

    To analyze the possible relationships between high sound pressure levels in the classroom and performance in the use of lexical and phonological routes in reading and writing. This consisted on a quantitative and exploratory study. The following measures were carried out: acoustic measurement, using the dosimeter, visual inspection of the external auditory canal, tonal audiometry thresholds, speech recognition tests and acoustic immittance; instrument for evaluation of reading and writing of isolated words. The non-parametric χ² test and Fisher's exact test were used for data analysis. The results of acoustic measurements in 4 schools in Santa Maria divided the sample of 87 children of third and fourth years of primary school, aged 8 to 10 years, in 2 groups. The 1st group was exposed to sound levels higher than 80 dB(A) (Study group) and the 2nd group at levels lower than 80 dB(A) (Control group). Higher prevalence of correct answers in reading and writing of nonwords, reading irregular words and frequency effect were observed. Predominance of correct answers in the writing of irregular words was observed in the Control group. For the Study group, a higher number of type errors neologism in reading and writing were observed, especially regarding the writing of nonwords and the extension effect; fewer errors of lexicalization type and verbal paragraphy in writing were observed. In assessing the reading and writing skills, children in the Study group exposed to high noise levels had poorer performance in the use of lexical and phonological routes, both in reading and in writing.

  14. Full range nuclear power plant steam generator level control system

    International Nuclear Information System (INIS)

    Geets, J.M.

    1988-01-01

    In a method of controlling feedwater level in a steam generator of a pressurized water reactor nuclear power plant, the steam generator having secondary loop feedwater lines. The method is described including the steps of outputting a first signal from a first three-mode controller to control feedwater flow through the secondary loop feedwater lines at reactor power levels below a predetermined percentage, and outputting a second signal from a second three-mode controller to control feedwater flow through the secondary loop feedwater lines at reactor power levels above the predetermined percentage. The improvement in combination therewith comprises: receiving the first and second signals at a transition controller means; generating a first feedwater temperature-dependent function; operating on the first input signal with the first temperature dependent function to produce a third signal; generating a second feedwater temperature-dependent function; operating on the second input signal with the second temperature-dependent function to produce a fourth signal; and adding the third and fourth signals resulting from the operating steps to control the feedwater flow through the secondary loop feedwater lines throughout an entire range of reactor load

  15. Numerical study of the impact of vegetation coverings on sound levels and time decays in a canyon street model.

    Science.gov (United States)

    Guillaume, G; Gauvreau, B; L'Hermite, P

    2015-01-01

    Given a constantly increasing urban population, the mitigation of environmental impacts caused by urbanization has become a critical concern. Sprawling cities accelerate the phenomenon of soil sealing, whose impacts relative to climatology, water cycle and ecology are substantial. The "VegDUD" project, which provides the framework for the present paper, lays out a possible alternative for limiting these deleterious effects through focusing on the role of vegetation in promoting sustainable urban development. The study presented herein addresses the beneficial effect of greening building facades and rooftops in terms of both acoustic level and sound-decay time indicators at low frequency third-octave bands. This is carried out through numerical simulations in the time-domain of sound propagation in a canyon street of infinite length for various scenarios of surface vegetalization. Numerical predictions show a more significant effect in the upper part and outside the street, depending on the location of the vegetalized surfaces, frequency bands and number of reflections on the treated materials. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Impurity levels and power loading in the PDX tokamak with high power neutral beam injection

    Energy Technology Data Exchange (ETDEWEB)

    Fonck, R.J.; Bell, M.; Bol, K.

    1982-10-01

    The PDX tokamak provides an experimental facility for the direct comparison of various impurity control techniques under reactor-like conditions. Four neutral beam lines can inject up to 6 MW for 300 ms. Carbon rail limiter discharges have been used to test the effectiveness of perpendicular injection, but non-disruptive full power operation for > 100 ms is difficult without extensive conditioning. Initial tests of a toroidal bumper limiter indicate reduced power loading and roughly similar impurity levels compared to the carbon rail limiter discharges. Poloidal divertor discharges with up to 5 MW of injected power are cleaner than similar circular discharges, and the power is deposited in a remote divertor chamber. High density divertor operation indicates a reduction of impurity flow velocity in the divertor and enhanced recycling in the divertor region during neutral injection.

  17. On-Chip electric power generation system from sound of portable music plyers and smartphones towerd portable uTAS

    NARCIS (Netherlands)

    Naito, T.; Kaji, N.; le Gac, Severine; Tokeshi, M.; van den Berg, Albert; Baba, Y.; Fujii, T.; Hibara, A.; Takeuchi, S.; Fukuba, T.

    2012-01-01

    This paper demonstrates electric generation from sound to minimize and integrate microfluidic systems for point of care testing or in-situ analysis. In this work, 5.4 volts and 50 mW DC was generated from sound through an earphone cable, which is a versatile system and able to actuate small size and

  18. Comparison of the Level of Substance P and Neurokinin A in Gingival Crevicular Fluid of Sound and Symptomatic Carious Primary Teeth by ELISA

    Directory of Open Access Journals (Sweden)

    Alireza Heidari

    2017-10-01

    Full Text Available Objectives: Pulpal inflammation is often associated with odontogenic pain. Dental pulp is abundantly innervated with sensory fibers encompassing neuropeptides. Neurokinin A (NKA and substance P (SP are important neuropeptides in the dental pulp that can cause neurogenic inflammation. Since no previous study has assessed dental pulp neuropeptides in children, this study aimed to compare the level of NKA and SP in gingival crevicular fluid (GCF of sound and symptomatic carious primary teeth.Materials and Methods: Samples of GCF were obtained of 20 sound and 20 painful carious primary teeth. Enzyme-linked immunosorbent assay (ELISA was used to quantify neuropeptides in GCF. Data were analyzed using paired t-test, ANOVA, Kolmogorov-Smirnov test and correlation coefficient test.Results: A significant difference was noted in the level of NKA in GCF of painful and sound teeth (2.23 pg/ml in painful, and 1.84 pg/ml in sound teeth, P<0.05. The difference between the two groups regarding SP was not significant (2.23 pg/ml in painful, and 2.02 pg/ml in sound teeth, P>0.05.Conclusions: The results showed that the level of NKA and SP was higher in GCF of painful teeth compared to that of sound teeth. This difference was statistically significant with regard to NKA. Thus, these neuropeptides can serve as indicators for pathological activities in teeth with symptomatic irreversible pulpitis.

  19. Extended Pulse-Powered Humidity-Freeze Cycling for Testing Module-Level Power Electronics

    Energy Technology Data Exchange (ETDEWEB)

    Hacke, Peter L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Rodriguez, Miguel [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kempe, Michael D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Repins, Ingrid L [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-28

    An EMI suppression capacitor (polypropylene film type) failed by 'popcorning' due to vapor outgassing in pulse powered humidity-freeze cycles. No shorts or shunts could be detected despite mildly corroded metallization visible in the failed capacitor. Humidity-freeze cycling is optimized to break into moisture barriers. However, further studies will be required on additional module level power electronic (MLPE) devices to optimize the stress testing for condensation to precipitate any weakness to short circuiting and other humidity/bias failure modes.

  20. Study on emergency action levels for Qinshan Nuclear Power Plant

    International Nuclear Information System (INIS)

    Yang Hongrun

    2005-10-01

    Based on Qinshan NPP, the technique scheme and many required considerations in the development of emergency action levels (EALs) for Nuclear Power Plants are discussed in detail, which include the selection of emergency classification systems, the criteria for development of EALs, the determination of initiating conditions (ICs) and EALs, the presentation of EALs (e.g. EALs matrix, emergency classification procedure chart in main control room, etc.), the use of emergency operating procedures (EOPs) and critical safety function status trees (CSFSTs) in emergency classification, etc. (authors)

  1. Bulk outlet temperature limits and increased reactor power levels

    Energy Technology Data Exchange (ETDEWEB)

    Jones, S.S.

    1958-06-13

    In a recent report, means of circumventing the present bulk temperature limits are suggested. These have definite merit but do not present an over-all picture of the problem. Therefore, this bulk temperature limit is reviewed in order to place the problem in its full perspective. A program of action is suggested that should lead to: Revised operating conditions and process piping to obtain higher power levels at the same bulk outlet temperature; The completion of production tests to permit higher bulk outlet temperatures with no significant changes in reactor piping; or Redesign of the effluent system to eliminate bulk temperatures as a reactor operating limit.

  2. Statistical Analysis for Subjective and Objective Evaluations of Dental Drill Sounds.

    Directory of Open Access Journals (Sweden)

    Tomomi Yamada

    Full Text Available The sound produced by a dental air turbine handpiece (dental drill can markedly influence the sound environment in a dental clinic. Indeed, many patients report that the sound of a dental drill elicits an unpleasant feeling. Although several manufacturers have attempted to reduce the sound pressure levels produced by dental drills during idling based on ISO 14457, the sound emitted by such drills under active drilling conditions may negatively influence the dental clinic sound environment. The physical metrics related to the unpleasant impressions associated with dental drill sounds have not been determined. In the present study, psychological measurements of dental drill sounds were conducted with the aim of facilitating improvement of the sound environment at dental clinics. Specifically, we examined the impressions elicited by the sounds of 12 types of dental drills in idling and drilling conditions using a semantic differential. The analysis revealed that the impressions of dental drill sounds varied considerably between idling and drilling conditions and among the examined drills. This finding suggests that measuring the sound of a dental drill in idling conditions alone may be insufficient for evaluating the effects of the sound. We related the results of the psychological evaluations to those of measurements of the physical metrics of equivalent continuous A-weighted sound pressure levels (LAeq and sharpness. Factor analysis indicated that impressions of the dental drill sounds consisted of two factors: "metallic and unpleasant" and "powerful". LAeq had a strong relationship with "powerful impression", calculated sharpness was positively related to "metallic impression", and "unpleasant impression" was predicted by the combination of both LAeq and calculated sharpness. The present analyses indicate that, in addition to a reduction in sound pressure level, refining the frequency components of dental drill sounds is important for creating a

  3. Utilization experience with research reactors of various power levels

    International Nuclear Information System (INIS)

    Chaudri, S.A.; Waheed, S.; Ahmad, S.

    1999-01-01

    Utilization of research reactor, PARR-1 at the power level of 5 MW, and then at 9 MW, after the up gradation and conversion from highly enriched uranium (HEU) to low enriched uranium (LEU), has been described. In addition, the type of work carried out around a smaller facility, PARR-2, with power rating of 27kW has also been discussed. Utilization of PARR-1 in the area of neutron diffraction, neutron capture studies, radioisotope production, neutron activation analysis, reactor physics, and in reactor controls etc has been illustrated. The benefits derived from the up gradation of the power for neutron diffraction studies, radioisotope production and neutron radiography have been discussed. The problem, which can be handed successfully on PARR-2, include neutron activation analysis, production of short-lived radioisotopes, and experimentation in reactor engineering and physics for training purposes. Suitable methodologies have been developed for the analysis of samples of varied nature using neutron activation technique, and the experience gained has been applied to the analysis of geological, environmental and biological samples and high purity materials. (author)

  4. Foley Sounds vs Real Sounds

    DEFF Research Database (Denmark)

    Trento, Stefano; Götzen, Amalia De

    2011-01-01

    This paper is an initial attempt to study the world of sound effects for motion pictures, also known as Foley sounds. Throughout several audio and audio-video tests we have compared both Foley and real sounds originated by an identical action. The main purpose was to evaluate if sound effects are...... applications of sound design such as advertisement or soundtracks for movies....

  5. A Rotating Speed Controller Design Method for Power Levelling by Means of Inertia Energy in Wind Power Systems

    DEFF Research Database (Denmark)

    Qin, Zian; Blaabjerg, Frede; Loh, Poh Chiang

    2015-01-01

    Power fluctuation caused by wind speed variations may be harmful for the stability of the power system as well as the reliability of the wind power converter, since it may induce thermal excursions in the solder joints of the power modules. Using the wind turbine rotor inertia energy for power...... leveling has been studied before, but no quantified analysis or generic design method have been found. In this paper, the transfer functions from the wind speed to electrical power, electromagnetic torque, and rotating speed are built based on which the rotating speed controller is designed...... in the frequency domain for power leveling. Moreover, the impact of other parameters on power leveling, including the time constant of maximum power point tracking (MPPT) and the rotor inertia, are also studied. With the proposed optimal design, the power fluctuations are mitigated as much as possible, while...

  6. Effect of reactor conditions on MSIV-ATWS power level

    International Nuclear Information System (INIS)

    Diamond, D.J.

    1987-01-01

    In a boiling water reactor (BWR) when there is closure of the main steam isolation valves (MSIVs), the energy generated in the core will be transferred to the pressure suppression pool (PSP) via steam that flows out of the relief valves. The pool has limited capacity as a heat sink and hence, if there is no reactor trip [an anticipated transient without scram (ATWS) event], there is the possibility that the pool temperature may rise beyond acceptable limits. The present study was undertaken to determine how the initial reactor conditions affect the power level during an MSIV-ATWS event. The time of interest is the 20- to 30-min period when it is assumed that the reactor is in a quasi equilibrium condition with the water level and pressure fixed, natural circulation conditions and no control rod movement or significant boron in the core. The initial conditions of interest are the time of the cycle and the operating state

  7. Low level waste management developments in UK nuclear power stations

    International Nuclear Information System (INIS)

    Passant, F.H.

    1988-01-01

    This paper discusses how the UK definition of low-level waste (LLW) as agreed between the Government regulating departments and the nuclear industry differs from that in the US and elsewhere. It is that the material is not suitable for disposal as ordinary refuse and that it has a specific activity level below 12 GBq/te beta-gamma and 4 GBq/te alpha. In other words it generally covers the low activity trash produced by the industry. The LLW produced as a result of power station operations can be grouped as drummable/non-drummable, compactable/non-compactable using low force compaction technology, and as burnable/non-burnable depending on the management practices locally

  8. Management of the high-level nuclear power facilities

    International Nuclear Information System (INIS)

    Preda, Marin

    2003-05-01

    This thesis approaches current issues in the management of the high power nuclear facilities and as such it appears to be important particularly for nuclear power plant operation topics. Of special interest are the failure events entailing possible catastrophic situations. The contents is structured onto ten chapters. The first chapter describes the operation regimes of the nuclear high power facilities. Highlighted here are the thesis scope and the original features of the work. The second chapter deals with operational policies developed in order to ensure the preventive maintenance of the nuclear installations. Also managing structures are described devoted to practical warranting the equipment safety function of non-classical power stations. In the third chapter cases of nuclear accidents are analyzed especially stressing the probabilistic risk and the operation regimes having in view the elimination of catastrophic events. In the fourth and fifth chapters the control of nuclear radiation emission is treated focusing the quality issue of nuclear installations required to avoid hazardous effects at level of nuclear reactor operation stage. At the same time set of operational measures is given here for preventing risks, catastrophes and chaotic situations. The chapter five presents both theoretical and practical approaches of the nuclear reactor core management concerning particularly the fuel testing, the water primary system and the quality of the involved equipment. In the sixth and seventh chapters issues of risk-quality correlations are approached as well as the structure of expert systems for monitoring the operational regimes of nuclear facilities. The efficiency of the power systems with nuclear injection is discussed and some original ideas developed in this work are evidenced in the eighth and ninth chapters. Presented are here both the operational principles and models of raising the efficiency of the interconnected nuclear stations and prices' policy

  9. Research and Implementation of Heart Sound Denoising

    Science.gov (United States)

    Liu, Feng; Wang, Yutai; Wang, Yanxiang

    Heart sound is one of the most important signals. However, the process of getting heart sound signal can be interfered with many factors outside. Heart sound is weak electric signal and even weak external noise may lead to the misjudgment of pathological and physiological information in this signal, thus causing the misjudgment of disease diagnosis. As a result, it is a key to remove the noise which is mixed with heart sound. In this paper, a more systematic research and analysis which is involved in heart sound denoising based on matlab has been made. The study of heart sound denoising based on matlab firstly use the powerful image processing function of matlab to transform heart sound signals with noise into the wavelet domain through wavelet transform and decomposition these signals in muli-level. Then for the detail coefficient, soft thresholding is made using wavelet transform thresholding to eliminate noise, so that a signal denoising is significantly improved. The reconstructed signals are gained with stepwise coefficient reconstruction for the processed detail coefficient. Lastly, 50HZ power frequency and 35 Hz mechanical and electrical interference signals are eliminated using a notch filter.

  10. Taxonomic level sufficient for assessing a moderate impact on macrobenthic communities in Puget Sound, Washington, USA

    International Nuclear Information System (INIS)

    Ferraro, S.P.; Cole, F.A.

    1992-01-01

    Macrobenthic data obtained using three sampling schemes (0.06-sq m x 8-cm-deep sampling unit and 1.0- or 0.5-mm-mesh sieves, and 0.1-sq m x 8-cm-deep sampling unit and 1.0-mm-mesh sieve) previously identified as optimal or near-optimal for detecting differences between a reference and a moderately impacted station when animals were identified to species were reanalyzed at the genus, family, order, and phylum level to determine the taxonomic level sufficient to detect differences between the stations with t-tests on five measures of community structure. Taxonomically sufficient levels for number of taxa were family in 1.0-mm-mesh samples and species in 0.5-mm-mesh samples. Specific identification was usually required for a Dominance, Shannon's, 1 - Simpson's, and McIntosh's Index in 1.0- and 0.5-mm-mesh samples, suggesting limits to the utility of the taxonomic sufficiency concept when using those indices to detect moderate impacts. This and a previous study indicate that one could reliably (alpha = 0.05, 1 - beta about 0.80) detect moderate benthic impacts at the study site on number of taxa and five other measures of community structure with five to seven replicate 0.06-sq m x 8-cm-deep, 1.0-mm-mesh samples per station and identification to family only. Taxonomic sufficiency can vary depending upon the animal size fraction sampled and the measure used

  11. Visual bias in subjective assessments of automotive sounds

    DEFF Research Database (Denmark)

    Ellermeier, Wolfgang; Legarth, Søren Vase

    2006-01-01

    In order to evaluate how strong the influence of visual input on sound quality evaluation may be, a naive sample of 20 participants was asked to judge interior automotive sound recordings while simultaneously being exposed to pictures of cars. twenty-two recordings of second-gear acceleration pre...... accounted for by the pictures was roughly one fifth of the variance due to the sounds themselves. In physical terms, the picture manipulation shifted ratings of powerfulness by what a change in overall sound-pressure level of approximately 2-3 decibels would accomplish....

  12. SoundCompass: a distributed MEMS microphone array-based sensor for sound source localization.

    Science.gov (United States)

    Tiete, Jelmer; Domínguez, Federico; da Silva, Bruno; Segers, Laurent; Steenhaut, Kris; Touhafi, Abdellah

    2014-01-23

    Sound source localization is a well-researched subject with applications ranging from localizing sniper fire in urban battlefields to cataloging wildlife in rural areas. One critical application is the localization of noise pollution sources in urban environments, due to an increasing body of evidence linking noise pollution to adverse effects on human health. Current noise mapping techniques often fail to accurately identify noise pollution sources, because they rely on the interpolation of a limited number of scattered sound sensors. Aiming to produce accurate noise pollution maps, we developed the SoundCompass, a low-cost sound sensor capable of measuring local noise levels and sound field directionality. Our first prototype is composed of a sensor array of 52 Microelectromechanical systems (MEMS) microphones, an inertial measuring unit and a low-power field-programmable gate array (FPGA). This article presents the SoundCompass's hardware and firmware design together with a data fusion technique that exploits the sensing capabilities of the SoundCompass in a wireless sensor network to localize noise pollution sources. Live tests produced a sound source localization accuracy of a few centimeters in a 25-m2 anechoic chamber, while simulation results accurately located up to five broadband sound sources in a 10,000-m2 open field.

  13. SoundCompass: A Distributed MEMS Microphone Array-Based Sensor for Sound Source Localization

    Directory of Open Access Journals (Sweden)

    Jelmer Tiete

    2014-01-01

    Full Text Available Sound source localization is a well-researched subject with applications ranging from localizing sniper fire in urban battlefields to cataloging wildlife in rural areas. One critical application is the localization of noise pollution sources in urban environments, due to an increasing body of evidence linking noise pollution to adverse effects on human health. Current noise mapping techniques often fail to accurately identify noise pollution sources, because they rely on the interpolation of a limited number of scattered sound sensors. Aiming to produce accurate noise pollution maps, we developed the SoundCompass, a low-cost sound sensor capable of measuring local noise levels and sound field directionality. Our first prototype is composed of a sensor array of 52 Microelectromechanical systems (MEMS microphones, an inertial measuring unit and a low-power field-programmable gate array (FPGA. This article presents the SoundCompass’s hardware and firmware design together with a data fusion technique that exploits the sensing capabilities of the SoundCompass in a wireless sensor network to localize noise pollution sources. Live tests produced a sound source localization accuracy of a few centimeters in a 25-m2 anechoic chamber, while simulation results accurately located up to five broadband sound sources in a 10,000-m2 open field.

  14. SoundCompass: A Distributed MEMS Microphone Array-Based Sensor for Sound Source Localization

    Science.gov (United States)

    Tiete, Jelmer; Domínguez, Federico; da Silva, Bruno; Segers, Laurent; Steenhaut, Kris; Touhafi, Abdellah

    2014-01-01

    Sound source localization is a well-researched subject with applications ranging from localizing sniper fire in urban battlefields to cataloging wildlife in rural areas. One critical application is the localization of noise pollution sources in urban environments, due to an increasing body of evidence linking noise pollution to adverse effects on human health. Current noise mapping techniques often fail to accurately identify noise pollution sources, because they rely on the interpolation of a limited number of scattered sound sensors. Aiming to produce accurate noise pollution maps, we developed the SoundCompass, a low-cost sound sensor capable of measuring local noise levels and sound field directionality. Our first prototype is composed of a sensor array of 52 Microelectromechanical systems (MEMS) microphones, an inertial measuring unit and a low-power field-programmable gate array (FPGA). This article presents the SoundCompass’s hardware and firmware design together with a data fusion technique that exploits the sensing capabilities of the SoundCompass in a wireless sensor network to localize noise pollution sources. Live tests produced a sound source localization accuracy of a few centimeters in a 25-m2 anechoic chamber, while simulation results accurately located up to five broadband sound sources in a 10,000-m2 open field. PMID:24463431

  15. Power estimation on functional level for programmable processors

    Directory of Open Access Journals (Sweden)

    M. Schneider

    2004-01-01

    Full Text Available In diesem Beitrag werden verschiedene Ansätze zur Verlustleistungsschätzung von programmierbaren Prozessoren vorgestellt und bezüglich ihrer Übertragbarkeit auf moderne Prozessor-Architekturen wie beispielsweise Very Long Instruction Word (VLIW-Architekturen bewertet. Besonderes Augenmerk liegt hierbei auf dem Konzept der sogenannten Functional-Level Power Analysis (FLPA. Dieser Ansatz basiert auf der Einteilung der Prozessor-Architektur in funktionale Blöcke wie beispielsweise Processing-Unit, Clock-Netzwerk, interner Speicher und andere. Die Verlustleistungsaufnahme dieser Bl¨ocke wird parameterabhängig durch arithmetische Modellfunktionen beschrieben. Durch automatisierte Analyse von Assemblercodes des zu schätzenden Systems mittels eines Parsers können die Eingangsparameter wie beispielsweise der erzielte Parallelitätsgrad oder die Art des Speicherzugriffs gewonnen werden. Dieser Ansatz wird am Beispiel zweier moderner digitaler Signalprozessoren durch eine Vielzahl von Basis-Algorithmen der digitalen Signalverarbeitung evaluiert. Die ermittelten Schätzwerte für die einzelnen Algorithmen werden dabei mit physikalisch gemessenen Werten verglichen. Es ergibt sich ein sehr kleiner maximaler Schätzfehler von 3%. In this contribution different approaches for power estimation for programmable processors are presented and evaluated concerning their capability to be applied to modern digital signal processor architectures like e.g. Very Long InstructionWord (VLIW -architectures. Special emphasis will be laid on the concept of so-called Functional-Level Power Analysis (FLPA. This approach is based on the separation of the processor architecture into functional blocks like e.g. processing unit, clock network, internal memory and others. The power consumption of these blocks is described by parameter dependent arithmetic model functions. By application of a parser based automized analysis of assembler codes of the systems to be estimated

  16. Effects of Listening to Music versus Environmental Sounds in Passive and Active Situations on Levels of Pain and Fatigue in Fibromyalgia.

    Science.gov (United States)

    Mercadíe, Lolita; Mick, Gérard; Guétin, Stéphane; Bigand, Emmanuel

    2015-10-01

    In fibromyalgia, pain symptoms such as hyperalgesia and allodynia are associated with fatigue. Mechanisms underlying such symptoms can be modulated by listening to pleasant music. We expected that listening to music, because of its emotional impact, would have a greater modulating effect on the perception of pain and fatigue in patients with fibromyalgia than listening to nonmusical sounds. To investigate this hypothesis, we carried out a 4-week study in which patients with fibromyalgia listened to either preselected musical pieces or environmental sounds when they experienced pain in active (while carrying out a physical activity) or passive (at rest) situations. Concomitant changes of pain and fatigue levels were evaluated. When patients listened to music or environmental sounds at rest, pain and fatigue levels were significantly reduced after 20 minutes of listening, with no difference of effect magnitude between the two stimuli. This improvement persisted 10 minutes after the end of the listening session. In active situations, pain did not increase in presence of the two stimuli. Contrary to our expectations, music and environmental sounds produced a similar relieving effect on pain and fatigue, with no benefit gained by listening to pleasant music over environmental sounds. Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  17. A Model to Determine the Level of Serum Aldosterone in the Workers Attributed to the Combined Effects of Sound Pressure Level, Exposure Time and Serum Potassium Level: A Field-Based Study

    Directory of Open Access Journals (Sweden)

    Parvin Nassiri

    2016-09-01

    Full Text Available Background Occupational exposure to excessive noise is one of the biggest work-related challenges in the world. This phenomenon causes the release of stress-related hormones, which in turn, negatively affects cardiovascular risk factors. Objectives The current study study aimed to determine the level of workers’ serum aldosterone in light of the combined effect of sound pressure level, exposure time and serum potassium level. Methods This cross-sectional, descriptive, analytical study was conducted on 45 workers of Gol-Gohar Mining and Industrial Company in the fall of 2014. The subjects were divided into three groups (one control and two case groups, each including 15 workers. Participants in the control group were selected from workers with administrative jobs (exposure to the background noise. On the other hand, participants in the case groups were selected from the concentrator and pelletizing factories exposed to excessive noise. Serum aldosterone and potassium levels of participants were assessed at three different time intervals: at the beginning of the shift and before exposure to noise (7:30 - 8:00 AM, during exposure to noise (10:00 - 10:30 AM, and during continuous exposure (1:30 - 2:00 PM. The obtained data were transferred into SPSS ver. 18. Repeated measures analysis of variance (ANOVA was used to develop the statistical model of workers’ aldosterone level in light of the combined effect of sound pressure level, exposure time, and serum potassium level. Results The results of the final statistical model to determine the level of serum aldosterone based on the combined effect of sound pressure level, exposure time and serum potassium level indicated that the sound pressure level had a significant influence on the human’s serum aldosterone level (P = 0.04. In addition, the effects of exposure time and serum potassium on aldosterone level were statistically significant with P-values of 0.008 and 0.001, respectively. Conclusions

  18. Calculation and reduction of the sound emissions of overhead power lines[Dissertation 17408]; Berechnung und Reduktion der tonalen Geraeuschemission von Hochspannungsfreileitungen

    Energy Technology Data Exchange (ETDEWEB)

    Straumann, U.

    2007-07-01

    In this dissertation, Ulrich Straumann of the Swiss Federal Institute of Technology in Zurich, Switzerland, discusses the reduction of sound emissions from overhead power lines. Corona-discharges occur during wet weather or when foggy or icing conditions prevail. Apart from these wide-band crackling noises, low-frequency, tonal emissions also occur. The CONOR (Corona Noise Reduction) project examined these emissions at a frequency of twice the mains frequency and looked for economically feasible solutions to the problems caused by them. The source of these emissions and the mechanisms causing them are discussed. Also, ways of calculating their strength are presented. The effects of varying cable geometry and construction are discussed, as are hydrophilic coatings that could be used to reduce sound emissions.

  19. Calculation and reduction of the sound emissions of overhead power lines;Dissertation 17408; Berechnung und Reduktion der tonalen Geraeuschemission von Hochspannungsfreileitungen

    Energy Technology Data Exchange (ETDEWEB)

    Straumann, U.

    2007-07-01

    In this dissertation, Ulrich Straumann of the Swiss Federal Institute of Technology in Zurich, Switzerland, discusses the reduction of sound emissions from overhead power lines. Corona-discharges occur during wet weather or when foggy or icing conditions prevail. Apart from these wide-band crackling noises, low-frequency, tonal emissions also occur. The CONOR (Corona Noise Reduction) project examined these emissions at a frequency of twice the mains frequency and looked for economically feasible solutions to the problems caused by them. The source of these emissions and the mechanisms causing them are discussed. Also, ways of calculating their strength are presented. The effects of varying cable geometry and construction are discussed, as are hydrophilic coatings that could be used to reduce sound emissions.

  20. Effect of gentamicin and levels of ambient sound on hearing screening outcomes in the neonatal intensive care unit: A pilot study.

    Science.gov (United States)

    Garinis, Angela C; Liao, Selena; Cross, Campbell P; Galati, Johnathan; Middaugh, Jessica L; Mace, Jess C; Wood, Anna-Marie; McEvoy, Lindsey; Moneta, Lauren; Lubianski, Troy; Coopersmith, Noe; Vigo, Nicholas; Hart, Christopher; Riddle, Artur; Ettinger, Olivia; Nold, Casey; Durham, Heather; MacArthur, Carol; McEvoy, Cynthia; Steyger, Peter S

    2017-06-01

    Hearing loss rates in infants admitted to neonatal intensive care units (NICU) run at 2-15%, compared to 0.3% in full-term births. The etiology of this difference remains poorly understood. We examined whether the level of ambient sound and/or cumulative gentamicin (an aminoglycoside) exposure affect NICU hearing screening results, as either exposure can cause acquired, permanent hearing loss. We hypothesized that higher levels of ambient sound in the NICU, and/or gentamicin dosing, increase the risk of referral on the distortion product otoacoustic emission (DPOAE) assessments and/or automated auditory brainstem response (AABR) screens. This was a prospective pilot outcomes study of 82 infants (sound pressure level dosimeter was used to collect daily sound exposure in the NICU for each neonate. Gentamicin dosing was also calculated for each infant, including the total daily dose based on body mass (mg/kg/day), as well as the total number of treatment days. DPOAE and AABR assessments were conducted prior to discharge to evaluate hearing status. Exclusion criteria included congenital infections associated with hearing loss, and congenital craniofacial or otologic abnormalities. The mean level of ambient sound was 62.9 dBA (range 51.8-70.6 dBA), greatly exceeding American Academy of Pediatrics (AAP) recommendation of 4172 Hz) was 44%. DPOAE referrals were significantly greater for infants receiving >2 days of gentamicin dosing compared to fewer doses (p = 0.004). The effect of sound exposure and gentamicin treatment on hearing could not be determined due to the low number of NICU infants without gentamicin exposure (for control comparisons). All infants were exposed to higher levels of ambient sound that substantially exceed AAP guidelines. More referrals were generated by DPOAE assessments than with AABR screens, with significantly more DPOAE referrals with a high-frequency F2 range, consistent with sound- and/or gentamicin-induced cochlear dysfunction. Adding

  1. Using the HISQUI29 to assess the sound quality levels of Spanish adults with unilateral cochlear implants and no contralateral hearing.

    Science.gov (United States)

    Calvino, Miryam; Gavilán, Javier; Sánchez-Cuadrado, Isabel; Pérez-Mora, Rosa M; Muñoz, Elena; Díez-Sebastián, Jesús; Lassaletta, Luis

    2016-09-01

    To evaluate cochlear implant (CI) users' self-reported level of sound quality and quality of life (QoL). Sound quality was self-evaluated using the hearing implant sound quality index (HISQUI29). HISQUI29 scores were further examined in three subsets. QoL was self-evaluated using the glasgow benefit inventory (GBI). GBI scores were further examined in three subsets. Possible correlations between the HISQUI29 and GBI were explored. Additional possible correlations between these scores and subjects' pure tone averages, speech perception scores, age at implantation, duration of hearing loss, duration of CI use, gender, and implant type were explored. Subjects derived a "moderate" sound quality level from their CI. Television, radio, and telephone tasks were easier in quiet than in background noise. 89 % of subjects reported their QoL benefited from having a CI. Mean total HISQUI29 score significantly correlated with all subcategories of the GBI. Age at implantation inversely correlated with the total HISQUI29 score and with television and radio understanding. Sentence in noise scores significantly correlated with all sound perception scores. Women had a better mean score in music perception and in telephone use than did men. CI users' self-reported levels of sound quality significantly correlated with their QoL. Cochlear implantation had a beneficial impact on subjects' QoL. Understanding speech is easier in quiet than in noise. Music perception remains a challenge for many CI users. The HISQUI29 and the GBI can provide useful information about the everyday effects of future treatment modalities, rehabilitation strategies, and technical developments.

  2. Contributions of Morphological Awareness Skills to Word-Level Reading and Spelling in First-Grade Children with and without Speech Sound Disorder

    Science.gov (United States)

    Apel, Kenn; Lawrence, Jessika

    2011-01-01

    Purpose: In this study, the authors compared the morphological awareness abilities of children with speech sound disorder (SSD) and children with typical speech skills and examined how morphological awareness ability predicted word-level reading and spelling performance above other known contributors to literacy development. Method: Eighty-eight…

  3. Light aircraft sound transmission studies - Noise reduction model

    Science.gov (United States)

    Atwal, Mahabir S.; Heitman, Karen E.; Crocker, Malcolm J.

    1987-01-01

    Experimental tests conducted on the fuselage of a single-engine Piper Cherokee light aircraft suggest that the cabin interior noise can be reduced by increasing the transmission loss of the dominant sound transmission paths and/or by increasing the cabin interior sound absorption. The validity of using a simple room equation model to predict the cabin interior sound-pressure level for different fuselage and exterior sound field conditions is also presented. The room equation model is based on the sound power flow balance for the cabin space and utilizes the measured transmitted sound intensity data. The room equation model predictions were considered good enough to be used for preliminary acoustical design studies.

  4. Changes in 63Hz third-octave band sound levels over 42 months recorded at four deep-ocean observatories

    NARCIS (Netherlands)

    Schaar, M. van der; Ainslie, M.A.; Robinson, S.P.; Prior, M.K.; André, M.

    2014-01-01

    The growing scientific and societal concerns about the effects of underwater sound on marine ecosystems have been recently recognised through the introduction of several international initiatives, like the International Quiet Ocean Experiment, aimed at measuring the environmental impact of ocean

  5. The power of positive and negative expectations to influence reported symptoms and mood during exposure to wind farm sound.

    Science.gov (United States)

    Crichton, Fiona; Dodd, George; Schmid, Gian; Gamble, Greg; Cundy, Tim; Petrie, Keith J

    2014-12-01

    Wind farm developments have been hampered by claims that sound from wind turbines causes symptoms and negative health reports in nearby residents. As scientific reviews have failed to identify a plausible link between wind turbine sound and health effects, psychological expectations have been proposed as an explanation for health complaints. Building on recent work showing negative expectations can create symptoms from wind turbines, we investigated whether positive expectations can produce the opposite effect, in terms of a reduction in symptoms and improvements in reported health. 60 participants were randomized to either positive or negative expectation groups and subsequently exposed to audible wind farm sound and infrasound. Prior to exposure, negative expectation participants watched a DVD incorporating TV footage about health effects said to be caused by infrasound produced by wind turbines. In contrast, positive expectation participants viewed a DVD that outlined the possible therapeutic effects of infrasound exposure. During exposure to audible windfarm sound and infrasound, symptoms and mood were strongly influenced by the type of expectations. Negative expectation participants experienced a significant increase in symptoms and a significant deterioration in mood, while positive expectation participants reported a significant decrease in symptoms and a significant improvement in mood. The study demonstrates that expectations can influence symptom and mood reports in both positive and negative directions. The results suggest that if expectations about infrasound are framed in more neutral or benign ways, then it is likely reports of symptoms or negative effects could be nullified.

  6. Distinguishing snoring sounds from breath sounds: a straightforward matter?

    Science.gov (United States)

    Rohrmeier, Christian; Herzog, Michael; Ettl, Tobias; Kuehnel, Thomas S

    2014-03-01

    Although snoring is a common problem, no unequivocal definition yet exists for this acoustic phenomenon. The primary study objective was to investigate whether snoring sounds can be distinguished at all clearly from breath sounds. Our secondary objective was to evaluate whether the sound pressure level in common use and psychoacoustic parameters are suitable for making this distinction. Twenty-five subjects exposed to 55 sound sequences were asked to decide whether these were breath sounds or snoring sounds, and to indicate how certain they were about their decision. The sound pressure level and the psychoacoustic parameters of loudness, sharpness, roughness, and fluctuation strength were then analyzed, and psychoacoustic annoyance was calculated from these parameters. Sixteen percent of the sound sequences could not be classified unequivocally, although the individual raters stated that they were still moderately certain about their decision. The sound pressure level and psychoacoustic parameters were capable of distinguishing between breath sounds and snoring sounds. The optimum for sensitivity and specificity was 76.9 and 78.8 %, respectively. Because snoring appears to be a subjective impression, at least in part, a generally valid acoustic definition therefore seems to be impossible. The sound pressure level and psychoacoustic parameters are suitable for distinguishing between breath sounds and snoring sounds. Nevertheless, when interpreting results, the only moderate validity of these parameters due to the absence of a universally valid definition of snoring should be taken into account.

  7. Development of computer program ENAUDIBL for computation of the sensation levels of multiple, complex, intrusive sounds in the presence of residual environmental masking noise

    Energy Technology Data Exchange (ETDEWEB)

    Liebich, R. E.; Chang, Y.-S.; Chun, K. C.

    2000-03-31

    The relative audibility of multiple sounds occurs in separate, independent channels (frequency bands) termed critical bands or equivalent rectangular (filter-response) bandwidths (ERBs) of frequency. The true nature of human hearing is a function of a complex combination of subjective factors, both auditory and nonauditory. Assessment of the probability of individual annoyance, community-complaint reaction levels, speech intelligibility, and the most cost-effective mitigation actions requires sensation-level data; these data are one of the most important auditory factors. However, sensation levels cannot be calculated by using single-number, A-weighted sound level values. This paper describes specific steps to compute sensation levels. A unique, newly developed procedure is used, which simplifies and improves the accuracy of such computations by the use of maximum sensation levels that occur, for each intrusive-sound spectrum, within each ERB. The newly developed program ENAUDIBL makes use of ERB sensation-level values generated with some computational subroutines developed for the formerly documented program SPECTRAN.

  8. Working levels in the coal fired power plant in Croatia

    International Nuclear Information System (INIS)

    Kovac, J.

    1996-01-01

    The exposure from man-made natural sources is called technologically enhanced natural radiation - TENR. One of the first sources of uranium and thorium which was detected not being connected with the nuclear industry, was found during energy production using fossil fuels. As the combustion of coal increases, so will the magnitude of environmental and human health hazards associated with trace elements and radionuclides mobilized by the coal fuel cycle. The large fraction of coal ash that does not find commercial application is usually dumped in the vicinity of the coal fired power plant (CFPP). The coal ash may contain enhanced levels of the natural radionuclides in the uranium and thorium series, especially fly ash. Among the decay products are the radon isotopes, 222 Rn, 220 Rn and 219 Rn, which are noble gases and thereby pose special problems in assessing the radiological hazard of fly ash. For that reason, investigations of the hazards were undertaken in the CFPP m Croatia, because the anthracite coal used for combustion has an average 10% sulphur and a variation of uranium. (author)

  9. Breath sounds

    Science.gov (United States)

    ... described as moist, dry, fine, and coarse. Rhonchi. Sounds that resemble snoring. They occur when air is blocked or air flow becomes rough through the large airways. Stridor. Wheeze-like sound heard when a person breathes. Usually it is ...

  10. Cortical response variation with different sound pressure levels: a combined event-related potentials and FMRI study.

    Directory of Open Access Journals (Sweden)

    Irene Neuner

    Full Text Available Simultaneous recording of electroencephalography (EEG and functional magnetic resonance imaging (fMRI provides high spatial and temporal resolution. In this study we combined EEG and fMRI to investigate the structures involved in the processing of different sound pressure levels (SPLs.EEG data were recorded simultaneously with fMRI from 16 healthy volunteers using MR compatible devices at 3 T. Tones with different SPLs were delivered to the volunteers and the N1/P2 amplitudes were included as covariates in the fMRI data analysis in order to compare the structures activated with high and low SPLs. Analysis of variance (ANOVA and ROI analysis were also performed. Additionally, source localisation analysis was performed on the EEG data.The integration of averaged ERP parameters into the fMRI analysis showed an extended map of areas exhibiting covariation with the BOLD signal related to the auditory stimuli. The ANOVA and ROI analyses also revealed additional brain areas other than the primary auditory cortex (PAC which were active with the auditory stimulation at different SPLs. The source localisation analyses showed additional sources apart from the PAC which were active with the high SPLs.The PAC and the insula play an important role in the processing of different SPLs. In the fMRI analysis, additional activation was found in the anterior cingulate cortex, opercular and orbito-frontal cortices with high SPLs. A strong response of the visual cortex was also found with the high SPLs, suggesting the presence of cross-modal effects.

  11. Imagining Sound

    DEFF Research Database (Denmark)

    Grimshaw, Mark; Garner, Tom Alexander

    2014-01-01

    We make the case in this essay that sound that is imagined is both a perception and as much a sound as that perceived through external stimulation. To argue this, we look at the evidence from auditory science, neuroscience, and philosophy, briefly present some new conceptual thinking on sound...... that accounts for this view, and then use this to look at what the future might hold in the context of imagining sound and developing technology....

  12. Serum testosterone, sex hormone-binding globulin and total calcium levels predict the calcaneal speed of sound in men.

    Science.gov (United States)

    Chin, Kok-Yong; Soelaiman, Ima-Nirwana; Mohamed, Isa Naina; Ngah, Wan Zurinah Wan

    2012-08-01

    Variations in sex hormones and the calcium balance can influence bone health in men. The present study aimed to examine the relationship between the calcaneal speed of sound and biochemical determinants of bone mass, such as sex hormones, parathyroid hormones and serum calcium. Data from 549 subjects from the Malaysian Aging Male Study, which included Malay and Chinese men aged 20 years and older residing in the Klang Valley, were used for analysis. The subjects' calcaneal speed of sound was measured, and their blood was collected for biochemical analysis. Two sets of multiple regression models were generated for the total/bioavailable testosterone and estradiol to avoid multicollinearity. The multiple regression results revealed that bioavailable testosterone and serum total calcium were significant predictors of the calcaneal speed of sound in the adjusted model. After adjustment for ethnicity and body mass index, only bioavailable testosterone remained significant; the total serum calcium was marginally insignificant. In a separate model, the total testosterone and sex hormone-binding globulin were significant predictors, whereas the total serum calcium was marginally insignificant. After adjustment for ethnicity and body mass index (BMI), the significance persisted for total testosterone and SHBG. After further adjustment for age, none of the serum biochemical determinants was a significant predictor of the calcaneal speed of sound. There is a significant age-dependent relationship between the calcaneal speed of sound and total testosterone, bioavailable testosterone and sex hormone-binding globulin in Chinese and Malay men in Malaysia. The relationship between total serum calcium and calcaneal speed of sound is ethnicity-dependent.

  13. Fluid Sounds

    DEFF Research Database (Denmark)

    and in architectural design. Aesthetics, psychoacoustics, perception, and cognition are all present in this expanding field embracing such categories as soundscape composition, sound art, sonic art, sound design, sound studies and auditory culture. Of greatest significance to the overall field is the investigation...... of sound, site and the social, and how the spatial, the visual, and the bodily interact in sonic environments, how they are constructed and how they are entangled in other practices. With the Seismograf special issue Fluid Sounds, we bring this knowledge into the dissemination of audio research itself...

  14. Feminized Power and Adversarial Advocacy: Levelling Arguments or Analyzing Them?

    Science.gov (United States)

    Condit, Celeste Michelle

    1989-01-01

    Examines the journalistic analysis of the 1988 Presidential Debates from a feminist perspective in order to identify the revisions needed in the debate process. Provides historical background of feminized power and adversarial advocacy. (MM)

  15. A Study of KHNP Nuclear Power Plant Technology Level Evaluation

    International Nuclear Information System (INIS)

    Yang, Seung Han; Lee, Sung Jin; Kim, Yo Han

    2016-01-01

    KHNP's 2030 mid and long term plan goal in technology field is securing global No. 1 NPP technology level. Quantifying technology level for this purpose, technology level at present should be surveyed. Technology level of South Korea has been surveyed by KISTEP (Korea Institute of S and T Evaluation and Planning) every two year but the technology level of KHNP has not been surveyed by any organization including KHNP itself. Also the size of technology surveyed by KISTEP was too broad to quantifying technology level of KHNP. In this paper, technology level of KHNP and South Korea are presented. In this study, NPP related technologies were divided into Level I and Level II technologies and conducted a survey for each Level II technologies using Delphi questionnaire survey that is widely used in technology level evaluation. The results of technology level and gap will be used from strategic point of view and also as a reference data for technology improvement planning

  16. Power Grid Construction Project Portfolio Optimization Based on Bi-level programming model

    Science.gov (United States)

    Zhao, Erdong; Li, Shangqi

    2017-08-01

    As the main body of power grid operation, county-level power supply enterprises undertake an important emission to guarantee the security of power grid operation and safeguard social power using order. The optimization of grid construction projects has been a key issue of power supply capacity and service level of grid enterprises. According to the actual situation of power grid construction project optimization of county-level power enterprises, on the basis of qualitative analysis of the projects, this paper builds a Bi-level programming model based on quantitative analysis. The upper layer of the model is the target restriction of the optimal portfolio; the lower layer of the model is enterprises’ financial restrictions on the size of the enterprise project portfolio. Finally, using a real example to illustrate operation proceeding and the optimization result of the model. Through qualitative analysis and quantitative analysis, the bi-level programming model improves the accuracy and normative standardization of power grid enterprises projects.

  17. An Improved Prediction Model for the Impact Sound Level of Lightweight Floors: Introducing Decoupled Floor-Ceiling and Beam-Plate Moment

    DEFF Research Database (Denmark)

    Mosharrof, Mohammad Sazzad; Brunskog, Jonas; Ljunggren, Fredrik

    2011-01-01

    To better understand the complex acoustic behaviour of lightweight building structures both experimental and theoretical approaches are necessary. Within the theoretical approach developing theoretical models is of great importance. The aim here is to further develop an existing method to predict...... the impact sound pressure level in a receiving room for a coupled floor structure where floor and ceiling are rigidly connected by beams. A theoretical model for predicting the impact sound level for a decoupled floor structure, which has no rigid mechanical connections between the floor and the ceiling......-third octave frequency bands. The predicted results from the model are compared with the results from the experiments on the decoupled floor-ceiling construction. The results gave agreements in line with comparisons regarding previous model. The effect of introducing beam-plate moment in the model is studied...

  18. Draft emergency action level guidelines for nuclear power plants

    International Nuclear Information System (INIS)

    1979-09-01

    This document is provided for interim use during the initial phases of the NRC effort to promptly improve emergency preparedness at operating nuclear power plants. Changes to the document can be expected as experience is gained in its use and public comments are received. Further, the Commission has initiated a rulemaking procedure, now scheduled for completion in January 1930 in the area of Emergency Planning and Preparedness. Additional requirements are to be expected when rulemaking is completed and some modifications to this document may be necessary. Four classes of Emergency Action Levels are established which replace the classes in Regulatory Guide 1.101, each with associated examples of initiating conditions. The classes are: - Notification of Unusual Event; - Alert; - Site Emergency; - General Emergency. The rationale for the notification and alert classes is to provide early and prompt notification of minor events which could lead to more serious consequences given operator error or equipment failure or which might be indicative of more serious conditions which are not yet fully realized. A gradation is provided to assure fuller response preparations for more serious indicators. The site emergency class reflects conditions where some significant releases are likely or are occurring but where a core melt situation is not indicated based on current information. In this situation full mobilization of emergency personnel in tie :near site environs is indicated as well as dispatch of monitoring teams and associated communications. The general emergency class involves actual or imminent substantial core degradation or malting with the potential for loss of containment. The immediate action for this class is sheltering (staying inside) rather thai evacuation until an assessment can be made that (1) an evacuation is indicated and (2) an evacuation, if indicated, can be completed prior to significant release and transport of radioactive material to the affected

  19. BEST-4, Fuel Cycle and Cost Optimization for Discrete Power Levels

    International Nuclear Information System (INIS)

    1973-01-01

    1 - Nature of physical problem solved: Determination of optimal power strategy for a fuel cycle, for discrete power levels and n temporal stages, taking into account replacement energy costs and de-rating. 2 - Method of solution: Dynamic programming. 3 - Restrictions on the complexity of the problem: Restrictions may arise from number of power levels and temporal stages, due to machine limitations

  20. Ion Thruster Power Levels Extended by a Factor of 10

    Science.gov (United States)

    Patterson, Michael J.

    2004-01-01

    In response to two NASA Office of Space Science initiatives, the NASA Glenn Research Center is now developing a 7-kW-class xenon ion thruster system for near-term solar-powered spacecraft and a 25-kW ion engine for nuclear-electric spacecraft. The 7-kW ion thruster and power processor can be throttled down to 1 kW and are applicable to 25-kW flagship missions to the outer planets, asteroids, and comets. This propulsion system was scaled up from the 2.5-kW ion thruster and power processor that was developed successfully by Glenn, Boeing, the Jet Propulsion Laboratory (JPL), and Spectrum Astro for the Deep Space 1 spacecraft. The 7-kW ion thruster system is being developed under NASA's Evolutionary Xenon Thruster (NEXT) project, which includes partners from JPL, Aerojet, Boeing, the University of Michigan, and Colorado State University.

  1. Why Do People Like Loud Sound? A Qualitative Study.

    Science.gov (United States)

    Welch, David; Fremaux, Guy

    2017-08-11

    Many people choose to expose themselves to potentially dangerous sounds such as loud music, either via speakers, personal audio systems, or at clubs. The Conditioning, Adaptation and Acculturation to Loud Music (CAALM) Model has proposed a theoretical basis for this behaviour. To compare the model to data, we interviewed a group of people who were either regular nightclub-goers or who controlled the sound levels in nightclubs (bar managers, musicians, DJs, and sound engineers) about loud sound. Results showed four main themes relating to the enjoyment of loud sound: arousal/excitement, facilitation of socialisation, masking of both external sound and unwanted thoughts, and an emphasis and enhancement of personal identity. Furthermore, an interesting incidental finding was that sound levels appeared to increase gradually over the course of the evening until they plateaued at approximately 97 dBA Leq around midnight. Consideration of the data generated by the analysis revealed a complex of influential factors that support people in wanting exposure to loud sound. Findings were considered in terms of the CAALM Model and could be explained in terms of its principles. From a health promotion perspective, the Social Ecological Model was applied to consider how the themes identified might influence behaviour. They were shown to influence people on multiple levels, providing a powerful system which health promotion approaches struggle to address.

  2. Level shifter for low power applications with body bias technique

    African Journals Online (AJOL)

    user

    power conservation has become major design concern for very large scale integration (VLSI) circuits and system design (Leblebici and Kang, 1998). It is also becoming a major concern for deep submicron (DSM) technologies. The shrinkage in size and addition of more function on integrated circuits(IC) has given rise to ...

  3. Unsound Sound

    DEFF Research Database (Denmark)

    Knakkergaard, Martin

    2016-01-01

    This article discusses the change in premise that digitally produced sound brings about and how digital technologies more generally have changed our relationship to the musical artifact, not simply in degree but in kind. It demonstrates how our acoustical conceptions are thoroughly challenged...... by the digital production of sound and, by questioning the ontological basis for digital sound, turns our understanding of the core term substance upside down....

  4. Integrated Human Factors Design Guidelines for Sound Interface

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jung Woon; Lee, Yong Hee; Oh, In Seok; Lee, Hyun Chul [KAERI, Daejeon (Korea, Republic of); Cha, Woo Chang [Kumoh National Univ. of Technology, Gumi (Korea, Republic of)

    2004-05-15

    Digital MMI, such as CRT, LCD etc., has been used increasingly in the design of main control room of the Korean standard nuclear power plants following the YGN units 3 and 4. The utilization of digital MMI may introduce various kind of sound interface into the control room design. In this project, for five top-level guideline items, including Sound Formats, Alarms, Sound Controls, Communications, and Environments, a total of 147 detail guidelines were developed and a database system for these guidelines was developed. The integrated human factors design guidelines for sound interface and the database system developed in this project will be useful for the design of sound interface of digital MMI in Korean NPPs.

  5. Integrated Human Factors Design Guidelines for Sound Interface

    International Nuclear Information System (INIS)

    Lee, Jung Woon; Lee, Yong Hee; Oh, In Seok; Lee, Hyun Chul; Cha, Woo Chang

    2004-05-01

    Digital MMI, such as CRT, LCD etc., has been used increasingly in the design of main control room of the Korean standard nuclear power plants following the YGN units 3 and 4. The utilization of digital MMI may introduce various kind of sound interface into the control room design. In this project, for five top-level guideline items, including Sound Formats, Alarms, Sound Controls, Communications, and Environments, a total of 147 detail guidelines were developed and a database system for these guidelines was developed. The integrated human factors design guidelines for sound interface and the database system developed in this project will be useful for the design of sound interface of digital MMI in Korean NPPs

  6. Sound classification of dwellings

    DEFF Research Database (Denmark)

    Rasmussen, Birgit

    2012-01-01

    National schemes for sound classification of dwellings exist in more than ten countries in Europe, typically published as national standards. The schemes define quality classes reflecting different levels of acoustical comfort. Main criteria concern airborne and impact sound insulation between...... dwellings, facade sound insulation and installation noise. The schemes have been developed, implemented and revised gradually since the early 1990s. However, due to lack of coordination between countries, there are significant discrepancies, and new standards and revisions continue to increase the diversity...... is needed, and a European COST Action TU0901 "Integrating and Harmonizing Sound Insulation Aspects in Sustainable Urban Housing Constructions", has been established and runs 2009-2013, one of the main objectives being to prepare a proposal for a European sound classification scheme with a number of quality...

  7. Sound Absorbers

    Science.gov (United States)

    Fuchs, H. V.; Möser, M.

    Sound absorption indicates the transformation of sound energy into heat. It is, for instance, employed to design the acoustics in rooms. The noise emitted by machinery and plants shall be reduced before arriving at a workplace; auditoria such as lecture rooms or concert halls require a certain reverberation time. Such design goals are realised by installing absorbing components at the walls with well-defined absorption characteristics, which are adjusted for corresponding demands. Sound absorbers also play an important role in acoustic capsules, ducts and screens to avoid sound immission from noise intensive environments into the neighbourhood.

  8. High system-safety level of nuclear power stations

    International Nuclear Information System (INIS)

    Lutz, H.R.

    1976-01-01

    A bluntly worded disquisition contrasting the incidence of death and harm to persons in the chemical industry with the low hazards in nuclear power stations. Quotes conclusions from a U.S. accident study that the risk from 100 large power stations is 100 times smaller than from chlorine manufacture and transport. The enclosure of a reactor in a safety container, the well understood effects of radioactivity on man, and the ease of measuring leakage well below safe limits, are safety features which he considers were not matched in the products and plant of the Seveso factory which suffered disaster. Questions the usefulness of warnings about nuclear dangers when chemical dangers are much greater and road dangers very much greater still. (R.W.S.)

  9. Photovoltaic Shading Testbed for Module-Level Power Electronics

    Energy Technology Data Exchange (ETDEWEB)

    Deline, C.; Meydbray, J.; Donovan, M.; Forrest, J.

    2012-05-01

    This document describes a repeatable test procedure that attempts to simulate shading situations, as would be experienced by typical residential rooftop photovoltaic (PV) systems. This type of shading test is particularly useful to evaluate the impact of different power conversion setups, including microinverters, DC power optimizers and string inverters, on overall system performance. The performance results are weighted based on annual estimates of shade to predict annual performance improvement. A trial run of the test procedure was conducted with a side by side comparison of a string inverter with a microinverter, both operating on identical 8kW solar arrays. Considering three different shade weighting conditions, the microinverter was found to increase production by 3.7% under light shading, 7.8% under moderate shading, and 12.3% under heavy shading, relative to the reference string inverter case. Detail is provided in this document to allow duplication of the test method at different test installations and for different power electronics devices.

  10. Repeated Measurement of Absolute and Relative Judgments of Loudness: Clinical Relevance for Prescriptive Fitting of Aided Target Gains for soft, Comfortable, and Loud, But Ok Sound Levels.

    Science.gov (United States)

    Formby, Craig; Payne, JoAnne; Yang, Xin; Wu, Delphanie; Parton, Jason M

    2017-02-01

    This study was undertaken with the purpose of streamlining clinical measures of loudness growth to facilitate and enhance prescriptive fitting of nonlinear hearing aids. Repeated measures of loudness at 500 and 3,000 Hz were obtained bilaterally at monthly intervals over a 6-month period from three groups of young adult listeners. All volunteers had normal audiometric hearing sensitivity and middle ear function, and all denied problems related to sound tolerance. Group 1 performed judgments of soft and loud, but OK for presentation of ascending sound levels. We defined these judgments operationally as absolute judgments of loudness. Group 2 initially performed loudness judgments across a continuum of seven loudness categories ranging from judgments of very soft to uncomfortably loud for presentation of ascending sound levels per the Contour Test of Loudness; we defined these judgments as relative judgments of loudness. In the same session, they then performed the absolute judgments for soft and loud, but OK sound levels. Group 3 performed the same set of loudness judgments as did group 2, but the task order was reversed such that they performed the absolute judgments initially within each test session followed by the relative judgments. The key findings from this study were as follows: (1) Within group, the absolute and relative tasks yielded clinically similar judgments for soft and for loud, but OK sound levels. These judgments were largely independent of task order, ear, frequency, or trial order within a given session. (2) Loudness judgments increased, on average, by ∼3 dB between the first and last test session, which is consistent with the commonly reported acclimatization effect reported for incremental changes in loudness discomfort levels as a consequence of chronic bilateral hearing aid use. (3) Measured and predicted comfortable judgments of loudness were in good agreement for the individual listener and for groups of listeners. These comfortable

  11. Using mineralogy and higher-level taxonomy as indicators of species sensitivity to pH: A case-study of Puget Sound

    Directory of Open Access Journals (Sweden)

    Shallin Busch

    2017-09-01

    Full Text Available Information on ecosystem sensitivity to global change can help guide management decisions. Here, we characterize the sensitivity of the Puget Sound ecosystem to ocean acidification by estimating, at a number of taxonomic levels, the direct sensitivity of its species. We compare sensitivity estimates based on species mineralogy and on published literature from laboratory experiments and field studies. We generated information on the former by building a database of species in Puget Sound with mineralogy estimates for all CaCO3-forming species. For the latter, we relied on a recently developed database and meta-analysis on temperate species responses to increased CO2. In general, species sensitivity estimates based on the published literature suggest that calcifying species are more sensitive to increased CO2 than non-calcifying species. However, this generalization is incomplete, as non-calcifying species also show direct sensitivity to high CO2 conditions. We did not find a strong link between mineral solubility and the sensitivity of species survival to changes in carbonate chemistry, suggesting that, at coarse scales, mineralogy plays a lesser role to other physiological sensitivities. Summarizing species sensitivity at the family level resulted in higher sensitivity scalar scores than at the class level, suggesting that grouping results at the class level may overestimate species sensitivity. This result raises caution about the use of broad generalizations on species response to ocean acidification, particularly when developing summary information for specific locations. While we have much to learn about species response to ocean acidification and how to generalize ecosystem response, this study on Puget Sound suggests that detailed information on species performance under elevated carbon dioxide conditions, summarized at the lowest taxonomic level possible, is more valuable than information on species mineralogy.

  12. On the sound radiation of a rolling tyre

    Science.gov (United States)

    Kropp, Wolfgang; Sabiniarz, Patrick; Brick, Haike; Beckenbauer, Thomas

    2012-04-01

    The sound radiation from rolling tyres is still not very well understood. Although details such as horn effect or directivity during rolling have been investigated, it is not clear which vibrational modes of the tyre structure are responsible for the radiated sound power. In this work an advanced tyre model based on Wave Guide Finite Elements is used in connection with a contact model validated in previous work. With these tools the tyre vibrations during rolling on an ISO surface are simulated. Starting from the calculated contact forces in time the amplitudes of the modes excited during rolling are determined as function of frequency. A boundary element model also validated in previous work is applied to predict the sound pressure level on a reference surface around a tyre placed on rigid ground as function of the modal composition of the tyre vibrations. Taking into account different modes when calculating the vibrational field as input into the boundary element calculations, it is possible to identify individual modes or groups of modes of special relevance for the radiated sound power. The results show that mainly low-order modes with relative low amplitudes but high radiation efficiency in the frequency range around 1 kHz are responsible for the radiated sound power at these frequencies, while those modes which are most strongly excited in that frequency range during rolling are irrelevant for the radiated sound power. This fact is very essential when focusing on the design of quieter tyres.

  13. The use of surface power for characterisation of structure-borne sound sources of low modal density

    DEFF Research Database (Denmark)

    Ohlrich, Mogens

    1996-01-01

    The use of the surface power methods for source characterisaiton of vibrating machinery of low modal density is investigated in this paper. It was demonstrated by Ohlrich and Larsen that this relatively simple, but very useful measurement technique for quantifying the vibratory strength...... of machinery, is very suitable in cases of high modal density, especially with respect to overall evaluation of machinery vibration characteristics and for estimation of the power produced by internal source mechanisms of the machine. Thus, it is envisaged that the method can be used in the development stage...... of new machines, in comparison studies of different machines, and in factory quality control to ensure that vibro-acoustic specifications are met. Carefully controlled experiments with an instrumented 3/4-scale structural model of a helicopter gearbox of low modal density, show that the surface power...

  14. Sound generator

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2008-01-01

    A sound generator, particularly a loudspeaker, configured to emit sound, comprising a rigid element (2) enclosing a plurality of air compartments (3), wherein the rigid element (2) has a back side (B) comprising apertures (4), and a front side (F) that is closed, wherein the generator is provided

  15. Sound generator

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2010-01-01

    A sound generator, particularly a loudspeaker, configured to emit sound, comprising a rigid element (2) enclosing a plurality of air compartments (3), wherein the rigid element (2) has a back side (B) comprising apertures (4), and a front side (F) that is closed, wherein the generator is provided

  16. Sound generator

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2007-01-01

    A sound generator, particularly a loudspeaker, configured to emit sound, comprising a rigid element (2) enclosing a plurality of air compartments (3), wherein the rigid element (2) has a back side (B) comprising apertures (4), and a front side (F) that is closed, wherein the generator is provided

  17. An objective measure for the sensitivity of room impulse response and its link to a diffuse sound field

    DEFF Research Database (Denmark)

    Prislan, Rok; Brunskog, Jonas; Jacobsen, Finn

    2014-01-01

    This study is relevant to acoustic measurements in reverberation rooms such as measurements of sound transmission, sound absorption, and sound power levels of noise sources. The study presents a quantitative measure for the diffuseness in a room, which is first introduced theoretically and sub......- sequently examined experimentally. The sensitivity of a room due to changes in the initial condi- tions is quantified by measuring a pair of impulse responses in a room differing only in the sound source position. Such changes are linked to mixing and the diffuse sound field. The measure is based...

  18. Level shifter for low power applications with body bias technique ...

    African Journals Online (AJOL)

    In present work three new designs of level shifter in 0.35μm technology using body bias approach have been presented. The level shifters, namely conventional type-I, conventional type-II and contention mitigated have been improved by varying the reverse body bias from 0.1V to 0.5 V. Circuits have been simulated in ...

  19. Toward the Next Level of PCB Usage in Power Electronic Converters

    NARCIS (Netherlands)

    De Jong, E.C.W.; Ferreira, B.J.A.; Bauer, P.

    2008-01-01

    A means for power electronics to exploit the level of 3-D packaging already being implemented in compact consumer products, such as digital cameras, is investigated in order to increase its power density. The increase in functionality and usage of printed circuit board (PCB) in power electronic

  20. Sound knowledge

    DEFF Research Database (Denmark)

    Kauffmann, Lene Teglhus

    of the research is to investigate what is considered to ‘work as evidence’ in health promotion and how the ‘evidence discourse’ influences social practices in policymaking and in research. From investigating knowledge practices in the field of health promotion, I develop the concept of sound knowledge...... making, which I call ‘sound knowledge’. Sound knowledge is an approach to knowledge that takes the reflexive considerations of actors in policymaking processes as well as in research about what knowledge is into account. Seeing knowledge as sound makes connections between different ideas, concepts...... and ideologies explicit. Furthermore, in relation to an anthropology of knowledge, sound knowledge also offers a reconsideration of the way anthropologists study knowledge, as it specifies that studying knowledge for anthropologists means studying what people consider as knowledge, in what circumstances...

  1. Power quality enhancement at distribution level utilizing the unified power quality conditioner (UPQC)

    Science.gov (United States)

    Khadkikar, Vinod

    The present doctoral work is based on the philosophy of optimal utilization of the available resources in a most effective and efficient way to improve the product efficiency and to reduce the overall cost. This work proposes a novel control philosophy termed as power angle control (PAC), in which both the series and shunt inverters share the load reactive power in co-ordination with each other without affecting the basic UPQC compensation capabilities. This eventually results in a better utilization of the series inverter, reduction in the shunt inverter rating to some extent and ultimately in the reduction of the overall cost of UPQC. Moreover, in this thesis work several other control approaches are also proposed, such as, unit vector template generation, quadrature voltage injection, generalized single-phase p-q theory and novel current unbalance compensation approach. All the developed concepts are successfully validated through digital simulation as well as extensive experimental investigations. Keywords. power quality, active power filter, unified power quality conditioner, reactive power compensation, harmonics compensation.

  2. ACCOUNTING OF REACTIVE POWER COMPENSATION LEVEL AT PAYMENT CALCULATION OF TECHNOLOGICAL CONSUMPTION (LOSSES OF ELECTRIC POWER FOR ITS TRANSMISSION IN POWER NETWORK

    Directory of Open Access Journals (Sweden)

    E. P. Zabello

    2005-01-01

    Full Text Available The method is proposed to make a correction in payment for consumption of reactive energy and power which is attributed to deviation of actual activation energy losses for reactive power compensation from their standard value. It is recommended to calculate standard loss values for every voltage level and actual loss values are to be determined with the help of application of remote electronic accounting means in the current mode of power consumption.

  3. More than 100 Years of Background-Level Sedimentary Metals, Nisqually River Delta, South Puget Sound, Washington

    Science.gov (United States)

    Takesue, Renee K.; Swarzenski, Peter W.

    2011-01-01

    The Nisqually River Delta is located about 25 km south of the Tacoma Narrows in the southern reach of Puget Sound. Delta evolution is controlled by sedimentation from the Nisqually River and erosion by strong tidal currents that may reach 0.95 m/s in the Nisqually Reach. The Nisqually River flows 116 km from the Cascade Range, including the slopes of Mount Rainier, through glacially carved valleys to Puget Sound. Extensive tidal flats on the delta consist of late-Holocene silty and sandy strata from normal river streamflow and seasonal floods and possibly from distal sediment-rich debris flows associated with volcanic and seismic events. In the early 1900s, dikes and levees were constructed around Nisqually Delta salt marshes, and the reclaimed land was used for agriculture and pasture. In 1974, U.S. Fish and Wildlife Service established the Nisqually National Wildlife Refuge on the reclaimed land to protect migratory birds; its creation has prevented further human alteration of the Delta and estuary. In October 2009, original dikes and levees were removed to restore tidal exchange to almost 3 km2 of man-made freshwater marsh on the Nisqually Delta.

  4. Deadbeat control of power leveling unit with bidirectional buck/boost DC/DC converter

    OpenAIRE

    Hamasaki, Shin-ichi; Mukai, Ryosuke; Yano, Yoshihiro; Tsuji, Mineo

    2014-01-01

    As a distributed generation system increases, a stable power supply becomes difficult. Thus control of power leveling (PL) unit is required to maintain the balance of power flow for irregular power generation. The unit is required to respond to change of voltage and bidirectional power flow. So the bidirectional buck/boost DC/DC converter is applied for the control of PL unit in this research. The PL unit with Electric double-layer capacitor (EDLC) is able to absorb change of power, and it is...

  5. Reactor power level monitoring system using an Alpha-Beta tracker

    International Nuclear Information System (INIS)

    Gaussa, L.W. Jr.; Greenberg, L.

    1987-01-01

    This patent describes a reactor power level monitor for a pressurized light water nuclear reactor, comprising: neutron detecting means for detecting neutrons emitted from the pressurized light water nuclear reactor and outputting a sample signal f(k) indicative of the neutrons detecting during a sampling period k having a predetermined length T; rate means for converting the sample signal k into a rate of power level change signal p(k) in accordance with rho(k) =rho(k-1) + β/T [f(k) - rho/sub rho/(k)], where p(k-1) is the rate of power level change for an immediately previous sampling period k-1, β is a constant with a value between zero and one, inclusive, and rho/sub rho/(k) is a predicted power level for a next sampling period; power signal means for converting the sample signal into a reactor power level signal p(k) in accordance with rho(k) - rho/sub rho/(k) - rho[f(k) - rho/sub rho/(k)], where α is equal to 2√β - β; and predicted power signal means for converting the sample signal into a predicted reactor power level signal p/sub p/(k) in accordance with rho/sub rho/(k) = rho(k-1) + T rho(k-1), is the power level signal for the immediately previous sampling period

  6. Population Exposure Estimates in Proximity to Nuclear Power Plants, Country-Level Aggregates

    Data.gov (United States)

    National Aeronautics and Space Administration — The Population Exposure Estimates in Proximity to Nuclear Power Plants, Country-Level Aggregates data set consists of country-level estimates of total, urban, and...

  7. Contributions of morphological awareness skills to word-level reading and spelling in first-grade children with and without speech sound disorder.

    Science.gov (United States)

    Apel, Kenn; Lawrence, Jessika

    2011-10-01

    In this study, the authors compared the morphological awareness abilities of children with speech sound disorder (SSD) and children with typical speech skills and examined how morphological awareness ability predicted word-level reading and spelling performance above other known contributors to literacy development. Eighty-eight first-grade students--44 students with SSD and no known history of language deficiencies, and 44 students with typical speech and language skills--completed an assessment battery designed to measure speech sound production, morphological awareness, phonemic awareness, letter-name knowledge, receptive vocabulary, word-level reading, and spelling abilities. The children with SSD scored significantly lower than did their counterparts on the morphological awareness measures as well as on phonemic awareness, word-level reading, and spelling tasks. Regression analyses suggested that morphological awareness predicted significant unique variance on the spelling measure for both groups and on the word-level reading measure for the children with typical skills. These results suggest that children with SSD may present with a general linguistic awareness insufficiency, which puts them at risk for difficulties with literacy and literacy-related tasks.

  8. Power Analysis for Cross Level Mediation in CRTs

    Science.gov (United States)

    Kelcey, Ben

    2014-01-01

    A common design in education research for interventions operating at a group or cluster level is a cluster randomized trial (CRT) (Bloom, 2005). In CRTs, intact clusters (e.g., schools) are assigned to treatment conditions rather than individuals (e.g., students) and are frequently an effective way to study interventions because they permit…

  9. Telephonic analysis of the snoring sound spectrum.

    Science.gov (United States)

    Seren, Erdal; Ilhanlı, Ilker; Bayar Muluk, Nuray; Cingi, Cemal; Hanci, Deniz

    2014-11-01

    Snoring is a sound caused by vibration of collapsed and/or unsteady airway walls of the pharynx and soft palate. We compared stored spectra of snoring sounds recorded via cell phone (CP) and a microphone placed over the head (head phone [HP]). Thirty-four snoring patients were included in this prospective study. Groups were identified by reference to body mass index (BMI) values: group 1, BMI Snoring sounds were recorded using CPs and HPs and digitally analyzed. We identified the frequencies with the highest snoring powers (F(max) values) and snoring sound intensity levels (SSILs). F(max) ranged from 520 to 985 Hz in HP recordings and from 845 to 1645 Hz in CP recordings. Snoring sound intensity level values increased in proportion to BMI and were 6 to 24 dB in HP recordings and 19 to 52 dB in CP recordings. Thus, the CP values of F(max) and SSIL were higher than the HP values. In obese patients of group 3, almost all F(max) and SSIL values were higher than those of groups 1 and 2. In particular, the CP F(max) values were elevated in such patients. The advanced technologies used in modern CPs may allow some snoring sounds in susceptible individuals to be defined as oronasal. Cell phone technology allows snoring to be evaluated in patients located in areas remote from a hospital. To explore the intensity of snoring and to postoperatively monitor the efficacy of surgery used to treat snoring, telephonic sound analysis is both new and effective and reduces the need for patient attendance at a hospital. Those experiencing severe snoring and/or who are obese should be told of what can be done to solve such problems. © The Author(s) 2014.

  10. Power levels in office equipment: Measurements of new monitors and personal computers

    Energy Technology Data Exchange (ETDEWEB)

    Roberson, Judy A.; Brown, Richard E.; Nordman, Bruce; Webber, Carrie A.; Homan, Gregory H.; Mahajan, Akshay; McWhinney, Marla; Koomey, Jonathan G.

    2002-05-14

    Electronic office equipment has proliferated rapidly over the last twenty years and is projected to continue growing in the future. Efforts to reduce the growth in office equipment energy use have focused on power management to reduce power consumption of electronic devices when not being used for their primary purpose. The EPA ENERGY STAR[registered trademark] program has been instrumental in gaining widespread support for power management in office equipment, and accurate information about the energy used by office equipment in all power levels is important to improving program design and evaluation. This paper presents the results of a field study conducted during 2001 to measure the power levels of new monitors and personal computers. We measured off, on, and low-power levels in about 60 units manufactured since July 2000. The paper summarizes power data collected, explores differences within the sample (e.g., between CRT and LCD monitors), and discusses some issues that arise in m etering office equipment. We also present conclusions to help improve the success of future power management programs.Our findings include a trend among monitor manufacturers to provide a single very low low-power level, and the need to standardize methods for measuring monitor on power, to more accurately estimate the annual energy consumption of office equipment, as well as actual and potential energy savings from power management.

  11. User instructions for levelized power generation cost codes using an IBM-type PC

    International Nuclear Information System (INIS)

    Coen, J.J.; Delene, J.G.

    1989-01-01

    Programs for the calculation of levelized power generation costs using an IBM or compatible PC are described. Cost calculations for nuclear plants and coal-fired plants include capital investment cost, operation and maintenance cost, fuel cycle cost, decommissioning cost, and total levelized power generation cost. 7 refs., 36 figs., 4 tabs

  12. Operating the Irish power system with increased levels of wind power

    DEFF Research Database (Denmark)

    Tuohy, A.; Denny, E.; Meibom, Peter

    2008-01-01

    This paper summarises some of the main impacts of large amounts of wind power installed in the island of Ireland. Using results from various studies performed on this system, it is shown that wind power will impact on all time frames, from seconds to daily planning of the system operation. Results...... from studies examining operation of the system with up to approximately 40% of electricity provided by wind show that some of the most important aspects to be considered include the type of wind turbine technology, the provision of reserve to accommodate wind forecasting error and the method used...

  13. The Power of Individual-level Drivers of Inventive Performance

    DEFF Research Database (Denmark)

    Zwick, Thomas; Frosch, Katharina; Hoisl, Karin

    2017-01-01

    We combine two lines of research on inventive and creative performance that have been separated before. We use empirical models of the performance of inventors over their careers based on an established theoretical framework of the drivers of creativity, the Knowledge, Skills, Abilities, and Other......, technology, patent, and time information. We show that educational level, skills acquired during the career, personality traits, career motivation, cognitive ability, and cognitive problem-solving style are significantly related to inventive performance....

  14. Equivalent threshold sound pressure levels (ETSPL) for Sennheiser HDA 280 supra-aural audiometric earphones in the frequency range 125 Hz to 8000 Hz

    DEFF Research Database (Denmark)

    Poulsen, Torben; Oakley, Sebastian

    2009-01-01

    Hearing threshold sound pressure levels were measured for the Sennheiser HDA 280 audiometric earphone. Hearing thresholds were measured for 25 normal hearing test subjects at the 11 audiometric test frequencies from 125 Hz to 8000 Hz. Sennheiser HDA 280 is a supra-aural earphone that may be seen...... laboratory measurements, ETSPL values are calculated for the ear simulator specified in IEC 60318-1. Fitting of earphone and coupler is discussed. The data may be used for a future update of the RETSPL standard for supra-aural audiometric earphones ISO 389-1....

  15. Equivalent threshold sound pressure levels for Sennheiser HDA 200 earphone and Etymotic Research ER-2 insert earphone in the frequency range 125 Hz to 16 kHz

    DEFF Research Database (Denmark)

    Han, Loc A; Poulsen, Torben

    1998-01-01

    Equivalent Threshold Sound Pressure Levels (ETSPLs) have been determined for the Sennheiser HDA 200 earphone and the Etymotic Research ER-2insert earphone. Thirty-one young normal-hearing test subjects participated and the thresholds were determined for all recommended frequencies in thefrequency...... range 125 Hz to 16 kHz. The results for the HDA 200 earphone are generally in very good agreement with the results from two otherinvestigations which are available at present. Only at 6 kHz is a 9 dB deviation found and at 8 kHz a 6 dB deviation is found between the threeinvestigations. For ER-2 it has...

  16. Sound Zones

    DEFF Research Database (Denmark)

    Møller, Martin Bo; Olsen, Martin

    2017-01-01

    Sound zones, i.e. spatially confined regions of individual audio content, can be created by appropriate filtering of the desired audio signals reproduced by an array of loudspeakers. The challenge of designing filters for sound zones is twofold: First, the filtered responses should generate...... an acoustic separation between the control regions. Secondly, the pre- and post-ringing as well as spectral deterioration introduced by the filters should be minimized. The tradeoff between acoustic separation and filter ringing is the focus of this paper. A weighted L2-norm penalty is introduced in the sound...

  17. Near-Field Acoustic Power Level Analysis of F31/A31 Open Rotor Model at Simulated Cruise Conditions, Technical Report II

    Science.gov (United States)

    Sree, Dave

    2015-01-01

    Near-field acoustic power level analysis of F31A31 open rotor model has been performed to determine its noise characteristics at simulated cruise flight conditions. The non-proprietary parts of the test data obtained from experiments in the 8x6 supersonic wind tunnel were provided by NASA-Glenn Research Center. The tone and broadband components of total noise have been separated from raw test data by using a new data analysis tool. Results in terms of sound pressure levels, acoustic power levels, and their variations with rotor speed, freestream Mach number, and input shaft power, with different blade-pitch setting angles at simulated cruise flight conditions, are presented and discussed. Empirical equations relating models acoustic power level and input shaft power have been developed. The near-field acoustic efficiency of the model at simulated cruise conditions is also determined. It is hoped that the results presented in this work will serve as a database for comparison and improvement of other open rotor blade designs and also for validating open rotor noise prediction codes.

  18. Nuclear power plant personnel entry level qualifications and training

    International Nuclear Information System (INIS)

    Jorgensen, C.C.; Haas, P.M.; Selby, D.L.; Lowry, J.C.

    1983-01-01

    This paper summarizes the early results and current status of a research program at ORNL which is intended to provide the methods and technical basis for NRC to initiate the use of the Systems Approach to Training (SAT) in the evaluation of training programs and entry level qualifications for NPP control room personnel. The program is an outgrowth of previous studies of simulator hardware and simulator training requirements under the Safety Related Operator Actions Program which recommended adaptation of a systems methodology to development and evaluation of NPP training programs

  19. 100 J-level pulse compression for peak power enhancement

    Science.gov (United States)

    Mironov, S. Yu.; Wheeler, J.; Gonin, R.; Cojocaru, G.; Ungureanu, R.; Banici, R.; Serbanescu, M.; Dabu, R.; Mourou, G.; Khazanov, E. A.

    2017-04-01

    A possibility of using self-phase modulation and cascaded quadratic nonlinearity effects for the enhancement of the temporal intensity profile is analysed theoretically in application to petawatt pulses at a kJ energy level. Preliminary experiments at a petawatt CETAL laser facility demonstrate the reduction of a pulse duration from 46 fs down to 29 fs by using the self-phase modulation effect and consequent spectral phase correction. These efficient methods offer an opportunity to economically enhance existing laser facility intensities and offer a broader range of high-intensity physics to become more readily attainable.

  20. Sound intensity

    DEFF Research Database (Denmark)

    Crocker, Malcolm J.; Jacobsen, Finn

    1998-01-01

    This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique.......This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique....

  1. Sound Intensity

    DEFF Research Database (Denmark)

    Crocker, M.J.; Jacobsen, Finn

    1997-01-01

    This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique.......This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique....

  2. A Flexible 360-Degree Thermal Sound Source Based on Laser Induced Graphene

    Directory of Open Access Journals (Sweden)

    Lu-Qi Tao

    2016-06-01

    Full Text Available A flexible sound source is essential in a whole flexible system. It’s hard to integrate a conventional sound source based on a piezoelectric part into a whole flexible system. Moreover, the sound pressure from the back side of a sound source is usually weaker than that from the front side. With the help of direct laser writing (DLW technology, the fabrication of a flexible 360-degree thermal sound source becomes possible. A 650-nm low-power laser was used to reduce the graphene oxide (GO. The stripped laser induced graphene thermal sound source was then attached to the surface of a cylindrical bottle so that it could emit sound in a 360-degree direction. The sound pressure level and directivity of the sound source were tested, and the results were in good agreement with the theoretical results. Because of its 360-degree sound field, high flexibility, high efficiency, low cost, and good reliability, the 360-degree thermal acoustic sound source will be widely applied in consumer electronics, multi-media systems, and ultrasonic detection and imaging.

  3. Interpolated Sounding and Gridded Sounding Value-Added Products

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, M. P. [Brookhaven National Laboratory (BNL), Upton, NY (United States); Toto, T. [Brookhaven National Laboratory (BNL), Upton, NY (United States)

    2016-03-01

    Standard Atmospheric Radiation Measurement (ARM) Climate Research Facility sounding files provide atmospheric state data in one dimension of increasing time and height per sonde launch. Many applications require a quick estimate of the atmospheric state at higher time resolution. The INTERPOLATEDSONDE (i.e., Interpolated Sounding) Value-Added Product (VAP) transforms sounding data into continuous daily files on a fixed time-height grid, at 1-minute time resolution, on 332 levels, from the surface up to a limit of approximately 40 km. The grid extends that high so the full height of soundings can be captured; however, most soundings terminate at an altitude between 25 and 30 km, above which no data is provided. Between soundings, the VAP linearly interpolates atmospheric state variables in time for each height level. In addition, INTERPOLATEDSONDE provides relative humidity scaled to microwave radiometer (MWR) observations.

  4. Core design experience of WWER-440 reactors when they working on increased power level

    International Nuclear Information System (INIS)

    Adeev, V.; Panov, A.; Melenchuk, I.

    2015-01-01

    The Kola NPP continues commercial operation of 2nd generation fuel (FA-2) and trial operation of 3rd generation fuel (FA-3), which has a number of design features providing the best operational characteristics. This report gives the results of VVER-440 core operation with FA-2 and FA-3 with enrichment increased up to 4.87%, and at the power level uprated to 107% of nominal power level. Brief analysis of obtained data is carried out. Peculiarities and techniques of developing loading patterns with new types of nuclear fuel for operation at the uprated power level are reviewed. (authors)

  5. System Level Power Optimization of Digital Audio Back End for Hearing Aids

    DEFF Research Database (Denmark)

    Pracny, Peter; Jørgensen, Ivan Harald Holger; Bruun, Erik

    2017-01-01

    This work deals with power optimization of the audio processing back end for hearing aids - the interpolation filter (IF), the sigma-delta (SD modulator and the Class D power amplifier (PA) as a whole. Specifications are derived and insight into the tradeoffs involved is used to optimize the inte......This work deals with power optimization of the audio processing back end for hearing aids - the interpolation filter (IF), the sigma-delta (SD modulator and the Class D power amplifier (PA) as a whole. Specifications are derived and insight into the tradeoffs involved is used to optimize...... to track the hardware and power demands as the tradeoffs of the system level parameters are investigated. The result is the digital part of the back end optimized with respect to power which provides audio performance comparable to state-of-theart. A combination of system level parameters leading...

  6. The Level of Power Quality Measurement and Evaluation in A Stone Crusher Plant

    Directory of Open Access Journals (Sweden)

    Mustafa ŞEKKELİ

    2009-03-01

    Full Text Available Both electric utilities and end users of electric power are becoming increasingly concerned about the quality of electric power. Quality of electrical energy in the electrical system that is requested continuous power (uninterrupted power, constant frequency and with constant amplitude can be explained by sinusoidal voltage. Deformation of voltage in the form of sinusoidal waveform is explained as a harmonic. Harmonics are most important factors in decreasing quality of energy in the electrical system. In industrial plants, existence of harmocins and voltage drop, causes serious problems both in plant and network. This problem affects the cost. In this study, a power quality measurements are carried out in stone crusher plant. Harmonics and voltage drop has been measured and evaluated with the power analyzer. In the power quality measurements, harmonic level of the plant is not so bad. However, it is recommended that compensation system with harmonic elimination can be established in plant.

  7. Modular Multi-level converter based HVDC System for Grid Connection of Offshore Wind Power Plant

    DEFF Research Database (Denmark)

    Gnanarathna, U.N.; Chaudhary, Sanjay Kumar; Gole, A.M.

    2010-01-01

    This paper explores the application of modular multi-level converters (MMC) as a means for harnessing the power from off-shore wind power plants. The MMC consists of a large number of simple voltage sourced converter (VSC) submodules that can be easily assembled into a converter for high-voltage ...

  8. 77 FR 20059 - License Amendment To Increase the Maximum Reactor Power Level, Florida Power & Light Company...

    Science.gov (United States)

    2012-04-03

    ... individuals (18 percent), respectively, living below the poverty level. Environmental Justice Impact Analysis... conditions in the vicinity of the PTN site. Environmental Justice Impacts The environmental justice impact... social impacts. Minority and low-income populations are subsets of the general public residing in the...

  9. Integrating High Levels of Variable Renewable Energy into Electric Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kroposki, Benjamin D. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-08-01

    As more variable renewable energy is integrated into electric power systems, there are a range of challenges and solutions to accommodating very high penetration levels. This presentation highlights some of the recent research in this area.

  10. Sound settlements

    DEFF Research Database (Denmark)

    Duelund Mortensen, Peder

    2013-01-01

    Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice......Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice...

  11. Sound Settlements

    DEFF Research Database (Denmark)

    Mortensen, Peder Duelund; Hornyanszky, Elisabeth Dalholm; Larsen, Jacob Norvig

    2013-01-01

    Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice......Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice...

  12. Little Sounds

    Directory of Open Access Journals (Sweden)

    Baker M. Bani-Khair

    2017-10-01

    Full Text Available The Spider and the Fly   You little spider, To death you aspire... Or seeking a web wider, To death all walking, No escape you all fighters… Weak and fragile in shape and might, Whatever you see in the horizon, That is destiny whatever sight. And tomorrow the spring comes, And the flowers bloom, And the grasshopper leaps high, And the frogs happily cry, And the flies smile nearby, To that end, The spider has a plot, To catch the flies by his net, A mosquito has fallen down in his net, Begging him to set her free, Out of that prison, To her freedom she aspires, Begging...Imploring...crying,  That is all what she requires, But the spider vows never let her free, His power he admires, Turning blind to light, And with his teeth he shall bite, Leaving her in desperate might, Unable to move from site to site, Tied up with strings in white, Wrapped up like a dead man, Waiting for his grave at night,   The mosquito says, Oh little spider, A stronger you are than me in power, But listen to my words before death hour, Today is mine and tomorrow is yours, No escape from death... Whatever the color of your flower…     Little sounds The Ant The ant is a little creature with a ferocious soul, Looking and looking for more and more, You can simply crush it like dead mold, Or you can simply leave it alone, I wonder how strong and strong they are! Working day and night in a small hole, Their motto is work or whatever you call… A big boon they have and joy in fall, Because they found what they store, A lesson to learn and memorize all in all, Work is something that you should not ignore!   The butterfly: I’m the butterfly Beautiful like a blue clear sky, Or sometimes look like snow, Different in colors, shapes and might, But something to know that we always die, So fragile, weak and thin, Lighter than a glimpse and delicate as light, Something to know for sure… Whatever you have in life and all these fields, You are not happier than a butterfly

  13. The sound of high winds. The effect of atmospheric stability on wind turbine sound and microphone noise

    International Nuclear Information System (INIS)

    Van den Berg, G.P.

    2006-01-01

    In this thesis issues are raised concerning wind turbine noise and its relationship to altitude dependent wind velocity. The following issues are investigated: what is the influence of atmospheric stability on the speed and sound power of a wind turbine?; what is the influence of atmospheric stability on the character of wind turbine sound?; how widespread is the impact of atmospheric stability on wind turbine performance: is it relevant for new wind turbine projects; how can noise prediction take this stability into account?; what can be done to deal with the resultant higher impact of wind turbine sound? Apart from these directly wind turbine related issues, a final aim was to address a measurement problem: how does wind on a microphone affect the measurement of the ambient sound level?

  14. The Level of Difficulty and Discrimination Power of the Basic Knowledge and Skills Examination (EXHCOBA.

    Directory of Open Access Journals (Sweden)

    Eduardo Backhoff Escudero

    2000-05-01

    Full Text Available The Basic Knowledge and Skills Examination (EXHCOBA is one of the few great-scale examinations in Mexico which has been publishing its psychometric parameters.  In this paper we describe the  item analysis results, regarding the exam’s difficulty level and discrimination power.  Results show that most of the items have a medium difficulty and a high discrimination power.  They also reveal that the mathematics items have better discrimination power levels than the ones which belong to social science.

  15. Lifetime Estimation of Electrolytic Capacitors in Fuel Cell Power Converter at Various Confidence Levels

    DEFF Research Database (Denmark)

    Zhou, Dao; Wang, Huai; Blaabjerg, Frede

    2016-01-01

    based lifetime expectancy of the individual capacitor and the capacitor bank is estimated in a fuel cell backup power converter operating in both standby mode and operation mode. The lifetime prediction of the capacitor banks at different confidence levels is also obtained.......DC capacitors in power electronic converters are a major constraint on improvement of the power density and the reliability. In this paper, according to the degradation data of tested capacitors, the lifetime model of the component is analyzed at various confidence levels. Then, the mission profile...

  16. Power level effects on thorium-based fuels in pressure-tube heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Bromley, B.P.; Edwards, G.W.R., E-mail: blair.bromley@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Sambavalingam, P. [Univ. of Ontario Inst. of Technology, Oshawa, Ontario (Canada)

    2016-06-15

    Lattice and core physics modeling and calculations have been performed to quantify the impact of power/flux levels on the reactivity and achievable burnup for 35-element fuel bundles made with Pu/Th or U-233/Th. The fissile content in these bundles has been adjusted to produce on the order of 20 MWd/kg burnup in homogeneous cores in a 700 MWe-class pressure-tube heavy water reactor, operating on a once-through thorium cycle. Results demonstrate that the impact of the power/flux level is modest for Pu/Th fuels but significant for U-233/Th fuels. In particular, high power/flux reduces the breeding and burnup potential of U-233/Th fuels. Thus, there may be an incentive to operate reactors with U-233/Th fuels at a lower power density or to develop alternative refueling schemes that will lower the time-average specific power, thereby increasing burnup.(author)

  17. `Power storage system` dealing with leveling of electric power use; Denryoku riyo no heijunka ni kotaeru `denryoku chozo system`

    Energy Technology Data Exchange (ETDEWEB)

    Igarashi, M. [Meidensha Corp., Tokyo (Japan)

    1996-06-28

    An overview is given on the development situation of a Zn-Br battery as a power storage system. The system is aimed at storing excess power at night and supplying the on-load demand during daytime. The power storage technology requires a large output and capacity of MWh level, long term stability and durability, and cost as low as pumped storage power generation. Four kinds of batteries have been examined to cope with the conditions, in which development of Zn-Br batteries along with Na-S batteries is in progress towards practicability. As a power conversion method for this system, GTO has been employed for a large capacity unit and IGBT for a medium/small capacity unit. The reliability of the Zn-Br batteries against leakage was improved by laminating each cell by hot plate welding. The service life was improved by using a material with a high bromine resistance in place of the conventional electrode constituent material. Although the battery efficiency was influenced by each resistance of electrode, film and electrolytic solution, distance between electrodes, temperature, etc., these correlations were clarified so as to establish the simulation technology. At present, the system realizes 50kW and 40kWh/m{sup 3}. 1 ref., 8 figs.

  18. Scalability of components for kW-level average power few-cycle lasers.

    Science.gov (United States)

    Hädrich, Steffen; Rothhardt, Jan; Demmler, Stefan; Tschernajew, Maxim; Hoffmann, Armin; Krebs, Manuel; Liem, Andreas; de Vries, Oliver; Plötner, Marco; Fabian, Simone; Schreiber, Thomas; Limpert, Jens; Tünnermann, Andreas

    2016-03-01

    In this paper, the average power scalability of components that can be used for intense few-cycle lasers based on nonlinear compression of modern femtosecond solid-state lasers is investigated. The key components of such a setup, namely, the gas-filled waveguides, laser windows, chirped mirrors for pulse compression and low dispersion mirrors for beam collimation, focusing, and beam steering are tested under high-average-power operation using a kilowatt cw laser. We demonstrate the long-term stable transmission of kW-level average power through a hollow capillary and a Kagome-type photonic crystal fiber. In addition, we show that sapphire substrates significantly improve the average power capability of metal-coated mirrors. Ultimately, ultrabroadband dielectric mirrors show negligible heating up to 1 kW of average power. In summary, a technology for scaling of few-cycle lasers up to 1 kW of average power and beyond is presented.

  19. Thermal analysis of two-level wind power converter under symmetrical grid fault

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede

    2013-01-01

    In this paper, the case of symmetrical grid fault when using the multi-MW wind turbine of partial-scale and full-scale two-level power converter are designed and investigated. Firstly, the different operation behaviors of the relevant power converters under the voltage dip will be described...... and analyzed. Simulations of different configurations regarding the loss distribution and the junction temperature of the power device are presented in respect to the various voltage dips. It is concluded that for both systems the power loss will change dramatically during the Low-Voltage Ride Through (LVRT......) condition as well as the junction temperature. For the full-scale wind turbine system, the most thermal stressed power device in the grid-side converter will appear at the grid voltage below 0.5 pu, and for the partial-scale wind turbine system, the most thermal stressed power device in the rotor...

  20. Power Flow Control through a Multi-Level H-Bridge-based Power Converter for Universal and Flexible Power Management in Future Electrical Grids

    DEFF Research Database (Denmark)

    Iov, Florin; Bifaretti, Steffano; Zanchetta, Pericle

    2008-01-01

    The paper proposes a novel power conversion system for Universal and Flexible Power Management (UNIFLEX-PM) in Future Electricity Network. The structure is based on three AC-DC converters each one connected to a different grid, (representing the main grid and/or various distributed generation...... systems) on the AC side, and linked together at DC side by suitable DC isolation modules. Each port of the UNIFLEX-PM system employs a conversion structure based on a three-phase 7-level AC-DC cascaded converter. Effective and accurate power flow control is demonstrated through simulation in Matlab...... and Simulink environment on a simplified model based on a two-port structure and using a Stationery Reference Frame based control solution. Control of different Power flow profiles has been successfully tested in numerous network conditions such as voltage unbalance, frequency excursions and harmonic...

  1. Second Sound

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 6. Second Sound - The Role of Elastic Waves. R Srinivasan. General Article Volume 4 Issue 6 June 1999 pp 15-19. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/004/06/0015-0019 ...

  2. Second Sound

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 3. Second Sound - Waves of Entropy and Temperature. R Srinivasan. General Article Volume 4 Issue 3 March 1999 pp 16-24. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/004/03/0016-0024 ...

  3. Second Sound

    Indian Academy of Sciences (India)

    as a function of q is called adispersion curve. Landau postulated. R Srinivasan is a Visiting. Professor at the Raman. Research Institute after retiring as .... Second sound was seen in solid 4He crystals by Ackermann and others in 1966. 4He will not solidify even at absolute zero of temperature unless one applies a pressure ...

  4. Second Sound

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 6. Second Sound - The Role of Elastic Waves. R Srinivasan. General Article Volume 4 Issue 6 June 1999 pp 15-19. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/004/06/0015-0019 ...

  5. Sound engineer

    CERN Document Server

    Mara, Wil

    2015-01-01

    "Readers will learn what it takes to succeed as a sound engineer. The book also explains the necessary educational steps, useful character traits, potential hazards, and daily job tasks related to this career. Sidebars include thought-provoking trivia. Questions in the backmatter ask for text-dependent analysis. Photos, a glossary, and additional resources are included."-- Provided by publisher.

  6. Sound Settlements

    DEFF Research Database (Denmark)

    Mortensen, Peder Duelund; Hornyanszky, Elisabeth Dalholm; Larsen, Jacob Norvig

    2013-01-01

    Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice...

  7. Sounding the warning bells: the need for a systems approach to understanding behaviour at rail level crossings.

    Science.gov (United States)

    Read, Gemma J M; Salmon, Paul M; Lenné, Michael G

    2013-09-01

    Collisions at rail level crossings are an international safety concern and have been the subject of considerable research effort. Modern human factors practice advocates a systems approach to investigating safety issues in complex systems. This paper describes the results of a structured review of the level crossing literature to determine the extent to which a systems approach has been applied. The measures used to determine if previous research was underpinned by a systems approach were: the type of analysis method utilised, the number of component relationships considered, the number of user groups considered, the number of system levels considered and the type of model described in the research. None of research reviewed was found to be consistent with a systems approach. It is recommended that further research utilise a systems approach to the study of the level crossing system to enable the identification of effective design improvements. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  8. Impact of high level penetration of Wind Turbines on Power System Transient Stability

    DEFF Research Database (Denmark)

    Kalogiannis, Theodoros; Llano, Enrique Muller; Hoseinzadeh, Bakhtyar

    2015-01-01

    One of the most relevant aspects in power systems is their reliability and robustness of maintaining the stability under large disturbances. System stability is a crucial aspect to consider when expanding the network, e.g. while increasing the levels of wind power penetration. Wind turbine...... generators differ from the conventional ones in their inertial contribution to the grid, therefore, in most cases the ability of the system to maintain a stable operation is declined. To investigate this, two standard models are designed in PowerFactory software. The first is used to characterize system...... components, the response of the wind turbines and thereupon to validate them, whereas the second is used to estimate the maximum levels of wind power penetration. Those levels mainly depend on the spinning reserve, the inertia of the system and the severity of the event. Rate of change of frequency...

  9. Wafer-level chip-scale packaging analog and power semiconductor applications

    CERN Document Server

    Qu, Shichun

    2015-01-01

    This book presents a state-of-art and in-depth overview in analog and power WLCSP design, material characterization, reliability, and modeling. Recent advances in analog and power electronic WLCSP packaging are presented based on the development of analog technology and power device integration. The book covers in detail how advances in semiconductor content, analog and power advanced WLCSP design, assembly, materials, and reliability have co-enabled significant advances in fan-in and fan-out with redistributed layer (RDL) of analog and power device capability during recent years. Along with new analog and power WLCSP development, the role of modeling is a key to assure successful package design. An overview of the analog and power WLCSP modeling and typical thermal, electrical, and stress modeling methodologies is also provided. This book also: ·         Covers the development of wafer-level power discrete packaging with regular wafer-level design concepts and directly bumping technology ·    �...

  10. Teaching Flexibly with Leveled Texts: More Power for Your Reading Block

    Science.gov (United States)

    Glasswell, Kathryn; Ford, Michael P.

    2010-01-01

    The practice of matching texts to readers is one that many teachers use and yet one that can become rigid and cumbersome with everyday classroom use. Here we discuss concerns about leveling and propose that by observing and listening to the students in our classes we can develop more powerful ways with leveled texts.

  11. A high-level power model for MPSoC on FPGA

    NARCIS (Netherlands)

    Piscitelli, R.; Pimentel, A.D.

    2011-01-01

    This paper presents a framework for high-level power estimation of multiprocessor systems-on-chip (MPSoC) architectures on FPGA. The technique is based on abstract execution profiles, called event signatures, and it operates at a higher level of abstraction than, e.g., commonly-used instruction-set

  12. Multi-Level Risk Assessment of a Power Plant Gas Turbine Applying ...

    African Journals Online (AJOL)

    Multi-Level Risk Assessment of a Power Plant Gas Turbine Applying the Criticality Index Model. ... Journal of the Nigerian Association of Mathematical Physics ... This study has carefully shown and expressed a step by step computation of the severity level of the Turbine component parts, using the Criticality Index model.

  13. A DC-DC Converter Efficiency Model for System Level Analysis in Ultra Low Power Applications

    Directory of Open Access Journals (Sweden)

    Benton H. Calhoun

    2013-06-01

    Full Text Available This paper presents a model of inductor based DC-DC converters that can be used to study the impact of power management techniques such as dynamic voltage and frequency scaling (DVFS. System level power models of low power systems on chip (SoCs and power management strategies cannot be correctly established without accounting for the associated overhead related to the DC-DC converters that provide regulated power to the system. The proposed model accurately predicts the efficiency of inductor based DC-DC converters with varying topologies and control schemes across a range of output voltage and current loads. It also accounts for the energy and timing overhead associated with the change in the operating condition of the regulator. Since modern SoCs employ power management techniques that vary the voltage and current loads seen by the converter, accurate modeling of the impact on the converter efficiency becomes critical. We use this model to compute the overall cost of two power distribution strategies for a SoC with multiple voltage islands. The proposed model helps us to obtain the energy benefits of a power management technique and can also be used as a basis for comparison between power management techniques or as a tool for design space exploration early in a SoC design cycle.

  14. PREFACE: Aerodynamic sound Aerodynamic sound

    Science.gov (United States)

    Akishita, Sadao

    2010-02-01

    The modern theory of aerodynamic sound originates from Lighthill's two papers in 1952 and 1954, as is well known. I have heard that Lighthill was motivated in writing the papers by the jet-noise emitted by the newly commercialized jet-engined airplanes at that time. The technology of aerodynamic sound is destined for environmental problems. Therefore the theory should always be applied to newly emerged public nuisances. This issue of Fluid Dynamics Research (FDR) reflects problems of environmental sound in present Japanese technology. The Japanese community studying aerodynamic sound has held an annual symposium since 29 years ago when the late Professor S Kotake and Professor S Kaji of Teikyo University organized the symposium. Most of the Japanese authors in this issue are members of the annual symposium. I should note the contribution of the two professors cited above in establishing the Japanese community of aerodynamic sound research. It is my pleasure to present the publication in this issue of ten papers discussed at the annual symposium. I would like to express many thanks to the Editorial Board of FDR for giving us the chance to contribute these papers. We have a review paper by T Suzuki on the study of jet noise, which continues to be important nowadays, and is expected to reform the theoretical model of generating mechanisms. Professor M S Howe and R S McGowan contribute an analytical paper, a valuable study in today's fluid dynamics research. They apply hydrodynamics to solve the compressible flow generated in the vocal cords of the human body. Experimental study continues to be the main methodology in aerodynamic sound, and it is expected to explore new horizons. H Fujita's study on the Aeolian tone provides a new viewpoint on major, longstanding sound problems. The paper by M Nishimura and T Goto on textile fabrics describes new technology for the effective reduction of bluff-body noise. The paper by T Sueki et al also reports new technology for the

  15. Wind turbine sound - metric and guidelines

    OpenAIRE

    Larsson, Conny; Öhlund, Olof

    2014-01-01

    The meteorological conditions vary over the globe but also change over the day and the year and vary a lot depending on the terrain for a certain location. The meteorological parameters govern both the wind turbine emission sound levels and the sound propagation conditions and therefore gives rise to different sound immission levels. Long-time measurements of meteorological effects on sound propagation from wind turbines over forest areas have been performed at two sites in Sweden for more th...

  16. Sound power measurement and certification

    International Nuclear Information System (INIS)

    MacKinnon, A.

    1993-01-01

    It is anticipated that there will be a substantial growth in the exploitation of renewable energy from the wind over the next few years. A major factor in this expected growth is the environmental acceptance or otherwise of wind turbines and in particular their noise characteristics. It is generally accepted within the turbine community that reliable methods of measuring and quantifying a turbine's acoustic signature are essential if this exploitation is to be realised. This paper will seek to review current practice both in the UK and further afield and will describe the development of a practical and reliable test method, which will aid the Wind Turbine Manufacturer, Developer and Planner. (author)

  17. Nonlinear Power-Level Control of the MHTGR Only with the Feedback Loop of Helium Temperature

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2013-02-01

    Full Text Available Power-level control is a crucial technique for the safe, stable and efficient operation of modular high temperature gas-cooled nuclear reactors (MHTGRs, which have strong inherent safety features and high outlet temperatures. The current power-level controllers of the MHTGRs need measurements of both the nuclear power and the helium temperature, which cannot provide satisfactory control performance and can even induce large oscillations when the neutron sensors are in error. In order to improve the fault tolerance of the control system, it is important to develop a power-level control strategy that only requires the helium temperature. The basis for developing this kind of control law is to give a state-observer of the MHTGR a relationship that only needs the measurement of helium temperature. With this in mind, a novel nonlinear state observer which only needs the measurement of helium temperature is proposed. This observer is globally convergent if there is no disturbance, and has the L2 disturbance attenuation performance if the disturbance is nonzero. The separation principle of this observer is also proven, which denotes that this observer can recover the performance of both globally asymptotic stabilizers and L2 disturbance attenuators. Then, a new dynamic output feedback power-level control strategy is established, which is composed of this observer and the well-built static state-feedback power-level control based upon iterative dissipation assignment (IDA-PLC. Finally, numerical simulation results show the high performance and feasibility of this newly-built dynamic output feedback power-level controller.

  18. Sound for digital video

    CERN Document Server

    Holman, Tomlinson

    2013-01-01

    Achieve professional quality sound on a limited budget! Harness all new, Hollywood style audio techniques to bring your independent film and video productions to the next level.In Sound for Digital Video, Second Edition industry experts Tomlinson Holman and Arthur Baum give you the tools and knowledge to apply recent advances in audio capture, video recording, editing workflow, and mixing to your own film or video with stunning results. This fresh edition is chockfull of techniques, tricks, and workflow secrets that you can apply to your own projects from preproduction

  19. Assessment of transfemoral amputees using a passive microprocessor-controlled knee versus an active powered microprocessor-controlled knee for level walking.

    Science.gov (United States)

    Creylman, Veerle; Knippels, Ingrid; Janssen, Paul; Biesbrouck, Evelyne; Lechler, Knut; Peeraer, Louis

    2016-12-19

    In transfemoral (TF) amputees, the forward propulsion of the prosthetic leg in swing has to be mainly carried out by hip muscles. With hip strength being the strongest predictor to ambulation ability, an active powered knee joint could have a positive influence, lowering hip loading and contributing to ambulation mobility. To assess this, gait of four TF amputees was measured for level walking, first while using a passive microprocessor-controlled prosthetic knee (P-MPK), subsequently while using an active powered microprocessor-controlled prosthetic knee (A-MPK). Furthermore, to assess long-term effects of the use of an A-MPK, a 4-weeks follow-up case study was performed. The kinetics and kinematics of the gait of four TF amputees were assessed while walking with subsequently the P-MPK and the A-MPK. For one amputee, a follow-up study was performed: he used the A-MPK for 4 weeks, his gait was measured weekly. The range of motion of the knee was higher on both the prosthetic and the sound leg in the A-MPK compared to the P-MPK. Maximum hip torque (HT) during early stance increased for the prosthetic leg and decreased for the sound leg with the A-MPK compared to the P-MPK. During late stance, the maximum HT decreased for the prosthetic leg. The difference between prosthetic and sound leg for HT disappeared when using the A-MPK. Also, an increase in stance phase duration was observed. The follow-up study showed an increase in confidence with the A-MPK over time. Results suggested that, partially due to an induced knee flexion during stance, HT can be diminished when walking with the A-MPK compared to the P-MPK. The single case follow-up study showed positive trends indicating that an adaptation time is beneficial for the A-MPK.

  20. Automatic and unsupervised snore sound extraction from respiratory sound signals.

    Science.gov (United States)

    Azarbarzin, Ali; Moussavi, Zahra M K

    2011-05-01

    In this paper, an automatic and unsupervised snore detection algorithm is proposed. The respiratory sound signals of 30 patients with different levels of airway obstruction were recorded by two microphones: one placed over the trachea (the tracheal microphone), and the other was a freestanding microphone (the ambient microphone). All the recordings were done simultaneously with full-night polysomnography during sleep. The sound activity episodes were identified using the vertical box (V-Box) algorithm. The 500-Hz subband energy distribution and principal component analysis were used to extract discriminative features from sound episodes. An unsupervised fuzzy C-means clustering algorithm was then deployed to label the sound episodes as either snore or no-snore class, which could be breath sound, swallowing sound, or any other noise. The algorithm was evaluated using manual annotation of the sound signals. The overall accuracy of the proposed algorithm was found to be 98.6% for tracheal sounds recordings, and 93.1% for the sounds recorded by the ambient microphone. © 2011 IEEE

  1. Sound response of superheated drop bubble detectors to neutrons

    International Nuclear Information System (INIS)

    Gao Size; Chen Zhe; Liu Chao; Ni Bangfa; Zhang Guiying; Zhao Changfa; Xiao Caijin; Liu Cunxiong; Nie Peng; Guan Yongjing

    2012-01-01

    The sound response of the bubble detectors to neutrons by using 252 Cf neutron source was described. Sound signals were filtered by sound card and PC. The short-time signal energy. FFT spectrum, power spectrum, and decay time constant were got to determine the authenticity of sound signal for bubbles. (authors)

  2. Method for leveling the power output of an electromechanical battery as a function of speed

    Science.gov (United States)

    Post, R.F.

    1999-03-16

    The invention is a method of leveling the power output of an electromechanical battery during its discharge, while at the same time maximizing its power output into a given load. The method employs the concept of series resonance, employing a capacitor the parameters of which are chosen optimally to achieve the desired near-flatness of power output over any chosen charged-discharged speed ratio. Capacitors are inserted in series with each phase of the windings to introduce capacitative reactances that act to compensate the inductive reactance of these windings. This compensating effect both increases the power that can be drawn from the generator before inductive voltage drops in the windings become dominant and acts to flatten the power output over a chosen speed range. The values of the capacitors are chosen so as to optimally flatten the output of the generator over the chosen speed range. 3 figs.

  3. Method for leveling the power output of an electromechanical battery as a function of speed

    Science.gov (United States)

    Post, Richard F.

    1999-01-01

    The invention is a method of leveling the power output of an electromechanical battery during its discharge, while at the same time maximizing its power output into a given load. The method employs the concept of series resonance, employing a capacitor the parameters of which are chosen optimally to achieve the desired near-flatness of power output over any chosen charged-discharged speed ratio. Capacitors are inserted in series with each phase of the windings to introduce capacitative reactances that act to compensate the inductive reactance of these windings. This compensating effect both increases the power that can be drawn from the generator before inductive voltage drops in the windings become dominant and acts to flatten the power output over a chosen speed range. The values of the capacitors are chosen so as to optimally flatten the output of the generator over the chosen speed range.

  4. Thermal analysis of multi-MW two-level wind power converter

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede; Mogens, Lau

    2012-01-01

    In this paper, the multi-MW wind turbine of partial-scale and full-scale two-level power converter with DFIG and direct-drive PMSG are designed and compared in terms of their thermal performance. Simulations of different configurations regarding loss distribution and junction temperature...... in the power device in the whole range of wind speed are presented and analyzed. It is concluded that in both partial-scale and full-scale power converter the most thermal stressed power device in the generator-side converter will have higher mean junction temperature and larger junction temperature...... fluctuation compared to grid-side converter at the rated wind speed. Moreover, the thermal performance of the generator-side converter in the partial-scale power converter becomes crucial around the synchronous operating point and should be considered carefully....

  5. A stationary reference frame current control for a multi-level H-bridge power converter for universal and flexible power management in future electricity network

    DEFF Research Database (Denmark)

    Ciobotaru, Mihai; Iov, Florin; Zanchetta, Pericle

    2008-01-01

    More "green" power provided by Distributed Generation will enter into the European electricity network in the near future. In order to control the power flow and to ensure proper and secure operation of this future grid, with an increased level of the renewable power, new power electronic...... for a multi-level cascaded H-bridges power converter used for grid applications. Harmonic content in the Point of Common Coupling, system response for bidirectional power flow, voltage and frequency excursions as well as voltage unbalances and asymmetries and low voltage ride-though capabilities are studied....

  6. Solidification of low-level radioactive wastes from nuclear power plants

    International Nuclear Information System (INIS)

    Filter, H.E.; Roberson, K.

    1979-01-01

    Test program results for the Dow system for solidification of low-level radioactive wastes from nuclear power plants are described. Simulated radioactive wastes containing 137 Cs and 60 Co and actual radioactive nuclear power plant wastes were solidified in the Dow system. All wastes were converted to homogeneous, liquid-free solids. Data are presented for solidified boiling water reactor (BWR) wastes, pressurized water reactor (PWR) wastes, mixed bed ion exchange resin (MBR), and filter aid (DE) slurries

  7. Use of Sound for Fish Protection at Power Facilities : A Historical Perspective of the State of the Art : Phase 1 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Thomas J.

    1994-11-01

    This paper summarizes the current state of the knowledge of fish hearing, i.e., what is known about fish response to sound, and provides a starting place for investigation into the use of sonic behavior modification to help solve pressing problems in the maintenance and recovery of anadromous and resident fish stocks of the Columbia River Basin. The challenge for scientists and engineers is to understand (1) how and what fish hear, and (2) how to use this knowledge to influence fish behavior or to factor fish sensory systems and behavior into the design of fish protection devices at power-production and water-control facilities. The sections that follow are a studied response to this challenge. In many respects, the search for effective and economical ways to modify fish behavior without physical intervention is one of the grails of fish management, particularly (although not exclusively), relative to electric power production. Within the Columbia River Basin and elsewhere, water is put to many uses not conducive to the health of indigenous fish. Irrigation, impoundment, and hydropower production frequently modify the riverine environment to the detriment of indigenous stocks while creating productive environments for competing or predatory species. The mechanisms of impact are numerous. Water project managers, when faced with the need to reduce impacts of their operations on fish health, generally attempt to divert fish from high-risk to lower-risk regions or manage the environment in such a way as to increase the survival prospects of impacted species. Almost without exception, risk reduction is accomplished by using physical barriers of one form or another. Unfortunately, physical barriers at water projects have several drawbacks, e.g., reducing available water flow for energy production and incurring high maintenance costs. In addition, recent studies (Sale et al. 1991) have documented that once these barriers are installed, they are rarely evaluated for

  8. Characterization of Yellow Seahorse Hippocampus kuda feeding click sound signals in a laboratory environment: an application of probability density function and power spectral density analyses

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, B.; Saran, A.K.; Kuncolienker, D.S.; Sreepada, R.A.; Haris, K.; Fernandes, W.A

    Do the sounds generated by different-sized fish of different sexes differ from each other in temporal, spectral or intensity patterns? Such differences would enable the development of passive acoustic techniques to locate seahorses in open water...

  9. Level-one modules library for DSNP: Dynamic Simulator for Nuclear Power-plants

    International Nuclear Information System (INIS)

    Saphier, D.

    1978-09-01

    The Dynamic Simulator for Nuclear Power-plants (DSNP) is a system of programs and data sets by which a nuclear power plant or part thereof can be simulated at different levels of sophistication. The acronym DSNP is used interchangeably for the DSNP language, for the DSNP precompiler, for the DSNP libraries, and for the DSNP document generator. The DSNP language is a set of simple block oriented statements, which together with the appropriate data, comprise a simulation of a nuclear power plant. The majority of the DSNP statements will result in the inclusion of a simulated physical module into the program. FORTRAN statements can be inserted with no restrictions among DSNP statements

  10. Soil radioactivity levels and radiation hazard assessment around a Thermal Power Plant

    International Nuclear Information System (INIS)

    Kumar, Mukesh; Kumar, Pankaj; Sharma, Somdutt; Agrawal, Anshu; Kumar, Rajesh; Prajith, Rama; Sahoo, B.K.

    2016-01-01

    Coal based thermal power plants further enhance the level of radioactivity in the environment, as burning of coal produces fly ash that can be released into the environment containing traces of 238 U, 232 Th and their decay products. Therefore, coal fired power plants are one of the major contributor towards the Technologically Enhanced Natural Radiation (TENR). Keeping this in view, a study of natural radioactivity in the soil of twenty five villages within 5 km radius around the Harduaganj Thermal Power Plant, Aligarh, UP, India is going on under a BRNS major project, to know the radiological implications on general population living around this plant

  11. Battery Recharging Issue for a Two-Power-Level Flywheel System

    Directory of Open Access Journals (Sweden)

    Janaína Gonçalves de Oliveira

    2010-01-01

    Full Text Available A novel battery recharging system for an all-electric driveline comprising a flywheel with a permanent magnet double wound synchronous machine (motor/generator is presented. The double winding enables two voltage levels and two different power levels. This topology supersedes other all-electric drivelines. The battery operates in a low-power regime supplying the average power whereas the flywheel delivers and absorbs power peaks, which are up to a higher order of magnitude. The topology presents new challenges for the power conversion system, which is the focus of this investigation. The main challenge is the control of the power flow to the battery when the vehicle is parked despite the decay of the flywheel machine voltage; which is dependent on its charge state, that is, rotational speed. The design and simulation of an unidirectional DC/DC buck/boost converter for a variable rotational speed flywheel is presented. Conventional power electronic converters are used in a new application, which can maintain a constant current or voltage on the battery side. Successful PI current control has been implemented and simulated, together with the complete closed loop system.

  12. Some technical and legal problems relating to the storage of high-level radioactive waste and the use of nuclear power sources on space satellites

    Energy Technology Data Exchange (ETDEWEB)

    Herkommer, E.; Wollenschlaeger, M.

    1985-04-01

    A brief survey is presented summarizing the main characteristics of radioactive wastes and the various waste management strategies. Subsequently, the technical and legal problems encountered with the final disposal of high-level radioactive waste and with the use of nuclear power sources on space satellites are reviewed. It is shown that both in terms of technology and law, a sound basis is already available upon which the problem of HAW disposal in space can be tackled. On the legal level, however, existing norms and regulations need to be supplemented and improved by more concrete provisions, and this task should be started now. An international agreement concerning HAW management in space is said to be indispensable.

  13. System-level power optimization for real-time distributed embedded systems

    Science.gov (United States)

    Luo, Jiong

    Power optimization is one of the crucial design considerations for modern electronic systems. In this thesis, we present several system-level power optimization techniques for real-time distributed embedded systems, based on dynamic voltage scaling, dynamic power management, and management of peak power and variance of the power profile. Dynamic voltage scaling has been widely acknowledged as an important and powerful technique to trade off dynamic power consumption and delay. Efficient dynamic voltage scaling requires effective variable-voltage scheduling mechanisms that can adjust voltages and clock frequencies adaptively based on workloads and timing constraints. For this purpose, we propose static variable-voltage scheduling algorithms utilizing criticalpath driven timing analysis for the case when tasks are assumed to have uniform switching activities, as well as energy-gradient driven slack allocation for a more general scenario. The proposed techniques can achieve closeto-optimal power savings with very low computational complexity, without violating any real-time constraints. We also present algorithms for power-efficient joint scheduling of multi-rate periodic task graphs along with soft aperiodic tasks. The power issue is addressed through both dynamic voltage scaling and power management. Periodic task graphs are scheduled statically. Flexibility is introduced into the static schedule to allow the on-line scheduler to make local changes to PE schedules through resource reclaiming and slack stealing, without interfering with the validity of the global schedule. We provide a unified framework in which the response times of aperiodic tasks and power consumption are dynamically optimized simultaneously. Interconnection network fabrics point to a new generation of power-efficient and scalable interconnection architectures for distributed embedded systems. As the system bandwidth continues to increase, interconnection networks become power/energy limited as

  14. Vibro-acoustic response and sound transmission loss analysis of functionally graded plates

    Science.gov (United States)

    Chandra, N.; Raja, S.; Nagendra Gopal, K. V.

    2014-10-01

    This paper presents analytical studies on the vibro-acoustic and sound transmission loss characteristics of functionally graded material (FGM) plates using a simple first-order shear deformation theory. The material properties of the plate are assumed to vary according to power law distribution of the constituent materials in terms of volume fraction. The sound radiation due to sinusoidally varying point load, uniformly distributed load and obliquely incident sound wave is computed by solving the Rayleigh integral with a primitive numerical scheme. Displacement, velocity, acceleration, radiated sound power level, radiated sound pressure level and radiation efficiency of FGM plate for varying power law index are examined. The sound transmission loss of the FGM plate for several incidence angles and varying power law index is studied in detail. It has been found that, for the plate being considered, the sound power level increases monotonically with increase in power law index at lower frequency range (0-500 Hz) and a non-monotonic trend is appeared towards higher frequencies for both point and distributed force excitations. Increased vibration and acoustic response is observed for ceramic-rich FGM plate at higher frequency band; whereas a similar trend is seen for metal-rich FGM plate at lower frequency band. The dBA values are found to be decreasing with increase in power law index. The radiation efficiency of ceramic-rich FGM plate is noticed to be higher than that of metal and metal-rich FGM plates. The transmission loss below the first resonance frequency is high for ceramic-rich FGM plate and low for metal-rich FGM plate and further depends on the specific material property. The study has found that increased transmission loss can be achieved at higher frequencies with metal-rich FGM plates.

  15. System-Level Value of a Gas Engine Power Plant in Electricity and Reserve Production

    Directory of Open Access Journals (Sweden)

    Antti Alahäivälä

    2017-07-01

    Full Text Available Power systems require a certain amount of flexibility to meet varying demand and to be able to cope with unexpected events, and this requirement is expected to increase with the emergence of variable power generation. In this paper, we focus on gas engine power plant technology and the beneficial influence its flexible operation can have on a power system. The study introduces the concept of a combined-cycle gas engine power plant (CCGE, which comprises a combination of several gas-fired combustion engines and a steam turbine. The operation of CCGE is then comprehensively analyzed in electricity and reserve production in the South African power system and compared with combined-cycle gas turbine (CCGT technology. Even though CCGE is a form of technology that has already been commercialized, it is rarely considered as a source of flexibility in the academic research. That is the notion providing the motivation for this study. Our core contribution is to show that the flexibility of CCGE can be valuable in power systems. The methodology is based on the unit-level model of the studied system and the solving of a day-ahead unit commitment problem for each day of the simulated 11-year period. The simulation studies reveal how a CCGE is able to offer system flexibility to follow hourly load variations and capacity to provide reserve power effectively.

  16. Interpolated Sounding and Gridded Sounding Value-Added Products

    Energy Technology Data Exchange (ETDEWEB)

    Toto, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Jensen, M. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-03-01

    Standard Atmospheric Radiation Measurement (ARM) Climate Research Facility sounding files provide atmospheric state data in one dimension of increasing time and height per sonde launch. Many applications require a quick estimate of the atmospheric state at higher time resolution. The INTERPOLATEDSONDE (i.e., Interpolated Sounding) Value-Added Product (VAP) transforms sounding data into continuous daily files on a fixed time-height grid, at 1-minute time resolution, on 332 levels, from the surface up to a limit of approximately 40 km. The grid extends that high so the full height of soundings can be captured; however, most soundings terminate at an altitude between 25 and 30 km, above which no data is provided. Between soundings, the VAP linearly interpolates atmospheric state variables in time for each height level. In addition, INTERPOLATEDSONDE provides relative humidity scaled to microwave radiometer (MWR) observations.The INTERPOLATEDSONDE VAP, a continuous time-height grid of relative humidity-corrected sounding data, is intended to provide input to higher-order products, such as the Merged Soundings (MERGESONDE; Troyan 2012) VAP, which extends INTERPOLATEDSONDE by incorporating model data. The INTERPOLATEDSONDE VAP also is used to correct gaseous attenuation of radar reflectivity in products such as the KAZRCOR VAP.

  17. Detection and adaptive cancellation of heart sound interference in tracheal sounds.

    Science.gov (United States)

    Cortés, Sandra; Jané, Raimon; Torres, Abel; Fiz, José Antonio; Morera, Josep

    2006-01-01

    Heart sound is often a serious source of noise in the analysis of respiratory sounds. The interference of heart sound is important when breath sounds are analyzed, since the intensity of heart sound is 1 to 10 times greater than the intensity of breath sound. Methods to reduce heart sound interference in breath sound analysis had been suggested. However, the majority of those methods require acquisition of an additional signal and knowledge of the spectral content of heart sound. In this paper it has been proposed an algorithm for the detection and adaptive filtering of heart sounds using only the sound signal and, minimizing distortion in the respiratory sound. The main components of the power spectral density (PSD) of the filtered tracheal sound are comparable with the PSD of the original signal. The experimental results shown reduction of the heart sound interference when the adaptive filter is applied. This kind of filter could facilitate the analysis and a better interpretation of the respiratory sound during spontaneous ventilation.

  18. Dynamic Output Feedback Power-Level Control for the MHTGR Based On Iterative Damping Assignment

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2012-06-01

    Full Text Available Because of its strong inherent safety features and high outlet temperature, the modular high temperature gas-cooled nuclear reactor (MHTGR is already seen as the central part of the next generation of nuclear plants. Such power plants are being considered for industrial applications with a wide range of power levels, and thus power-level control is an important technique for their efficient and stable operation. Stimulated by the high regulation performance provided by nonlinear controllers, a novel dynamic output-feedback nonlinear power-level regulator is developed in this paper based on the technique of iterative damping assignment (IDA. This control strategy can provide the L2 disturbance attenuation performance under modeling uncertainty or exterior disturbance, and can also guarantee the globally asymptotic closed-loop stability without uncertainty and disturbance. This newly built control strategy is then applied to the power-level regulation of the HTR-PM plant, and numerical simulation results show both the feasibility and high performance of this newly-built control strategy. Furthermore, the relationship between the values of the parameters and the performance of this controller is not only illustrated numerically but also analyzed theoretically.

  19. Nonlinear Adaptive Power-Level Control for Modular High Temperature Gas-Cooled Reactors

    Science.gov (United States)

    Dong, Zhe

    2013-04-01

    After the Fukushima nuclear accident, much more attention has to be drawn on the safety issues. The improvement of safety has already become the focus of the developing trend of the nuclear energy systems. Due to the inherent safety feature and the potential economic competitiveness, the modular high temperature gas-cooled reactor (MHTGR) has been seen as the central part of the next generation of nuclear plant (NGNP). Power-level control is one of the key techniques that guarantee the safe, stable and efficient operation for nuclear reactors. Since the MHTGR dynamics has the features of strong nonlinearity and uncertainty, in order to improve the operation performance, it is meaningful to develop the nonlinear adaptive power-level control law for the MHTGR. Based on using the natural dynamic features beneficial to system stabilization, a novel nonlinear adaptive power-level control is given for the MHTGR in this paper. It is theoretically proved that this newly-built controller does not only provide globally asymptotic closed-loop stability but is also adaptive to the system uncertainty. This control law is then applied to the power-level regulation of the pebble-bed MHTGR of the HTR-PM power plant. Numerical simulation results show the feasibility of this control law and the relationship between the performance and controller parameters.

  20. Power-Level Control for MHTGRs with Time-Delay in Helium Temperature Measurement

    Science.gov (United States)

    Dong, Zhe

    2014-06-01

    The modular high temperature gas-cooled reactor (MHTGR), which has the inherent safety feature, high thermal efficiency and satisfactory economic feasibility, can be applied for electricity and process heat production. Power-level control is an important technique for providing both the stable operation and load-following performance. Since the coolant temperature sensors of an MHTGR are usually installed near the primary side of the corresponding steam generator, there must be time-delay effect in the feedback loop of the coolant temperatures. Moreover, the measurement signal transducing may also induce time-delay effect. Therefore, it is meaningful to give the power-level control design method by considering this time-delay effect. In this paper, a simple output-feedback power-level control is proposed for the MHTGRs by using the delayed measurement signal of average reactor coolant temperature. In the aspect of theoretical analysis, a sufficient condition, under which it is well guaranteed that this newly-built power-level control is a globally asymptotic stabilizer, is firstly given. In the aspect of verification, numerical simulation results not only verify the feasibility of the theoretical results but also show the relationship between the performance and values of parameters of this novel power-level controller. The meaning of this work lies in two aspects. The first one is deeply revealing the relationship between the closed-loop stability and values of the controller parameters. The second one is giving the approach of designing a simple and effective power-level control strategy to suppress the negative influence induced by the time-delay in the feedback loop of the coolant temperatures.

  1. Energy Use and Power Levels in New Monitors and Personal Computers

    Energy Technology Data Exchange (ETDEWEB)

    Roberson, Judy A.; Homan, Gregory K.; Mahajan, Akshay; Nordman, Bruce; Webber, Carrie A.; Brown, Richard E.; McWhinney, Marla; Koomey, Jonathan G.

    2002-07-23

    Our research was conducted in support of the EPA ENERGY STAR Office Equipment program, whose goal is to reduce the amount of electricity consumed by office equipment in the U.S. The most energy-efficient models in each office equipment category are eligible for the ENERGY STAR label, which consumers can use to identify and select efficient products. As the efficiency of each category improves over time, the ENERGY STAR criteria need to be revised accordingly. The purpose of this study was to provide reliable data on the energy consumption of the newest personal computers and monitors that the EPA can use to evaluate revisions to current ENERGY STAR criteria as well as to improve the accuracy of ENERGY STAR program savings estimates. We report the results of measuring the power consumption and power management capabilities of a sample of new monitors and computers. These results will be used to improve estimates of program energy savings and carbon emission reductions, and to inform rev isions of the ENERGY STAR criteria for these products. Our sample consists of 35 monitors and 26 computers manufactured between July 2000 and October 2001; it includes cathode ray tube (CRT) and liquid crystal display (LCD) monitors, Macintosh and Intel-architecture computers, desktop and laptop computers, and integrated computer systems, in which power consumption of the computer and monitor cannot be measured separately. For each machine we measured power consumption when off, on, and in each low-power level. We identify trends in and opportunities to reduce power consumption in new personal computers and monitors. Our results include a trend among monitor manufacturers to provide a single very low low-power level, well below the current ENERGY STAR criteria for sleep power consumption. These very low sleep power results mean that energy consumed when monitors are off or in active use has become more important in terms of contribution to the overall unit energy consumption (UEC

  2. Energy Use and Power Levels in New Monitors and Personal Computers; TOPICAL

    International Nuclear Information System (INIS)

    Roberson, Judy A.; Homan, Gregory K.; Mahajan, Akshay; Nordman, Bruce; Webber, Carrie A.; Brown, Richard E.; McWhinney, Marla; Koomey, Jonathan G.

    2002-01-01

    Our research was conducted in support of the EPA ENERGY STAR Office Equipment program, whose goal is to reduce the amount of electricity consumed by office equipment in the U.S. The most energy-efficient models in each office equipment category are eligible for the ENERGY STAR label, which consumers can use to identify and select efficient products. As the efficiency of each category improves over time, the ENERGY STAR criteria need to be revised accordingly. The purpose of this study was to provide reliable data on the energy consumption of the newest personal computers and monitors that the EPA can use to evaluate revisions to current ENERGY STAR criteria as well as to improve the accuracy of ENERGY STAR program savings estimates. We report the results of measuring the power consumption and power management capabilities of a sample of new monitors and computers. These results will be used to improve estimates of program energy savings and carbon emission reductions, and to inform rev isions of the ENERGY STAR criteria for these products. Our sample consists of 35 monitors and 26 computers manufactured between July 2000 and October 2001; it includes cathode ray tube (CRT) and liquid crystal display (LCD) monitors, Macintosh and Intel-architecture computers, desktop and laptop computers, and integrated computer systems, in which power consumption of the computer and monitor cannot be measured separately. For each machine we measured power consumption when off, on, and in each low-power level. We identify trends in and opportunities to reduce power consumption in new personal computers and monitors. Our results include a trend among monitor manufacturers to provide a single very low low-power level, well below the current ENERGY STAR criteria for sleep power consumption. These very low sleep power results mean that energy consumed when monitors are off or in active use has become more important in terms of contribution to the overall unit energy consumption (UEC

  3. Transparent sound screens. [and their noise control efficiency in buildings

    Science.gov (United States)

    Bizo, F.; Draghici, R.

    1974-01-01

    Transparent sound screens consisting of glass (organic glass) plates placed at fixed angles with respect to the floor are considered. Noise levels in the screened area depend on the cumulative effect of direct, reverberated and refracted components of sound energy radiated by the source. This effect is analyzed on the analogy of the summation of electrical impedances. Inasmuch as under given circumstances sufficient noise control can be obtained, transparent screens seem to solve the problem of unimpeded supervision of installations in noisy workshops and power plants; in administrative buildings, computing centers, design bureaus, etc., they ensure acoustic comfort without space losses and without inspiring claustrophobia.

  4. Air-borne sound generated by sea waves.

    Science.gov (United States)

    Bolin, Karl; Åbom, Mats

    2010-05-01

    This paper describes a semi-empiric model and measurements of air-borne sound generated by breaking sea waves. Measurements have been performed at the Baltic Sea. Shores with different slopes and sediment types have been investigated. Results showed that the sound pressure level increased from 60 dB at 0.4 m wave height to 78 dB at 2.0 m wave height. The 1/3 octave spectrum was dependent on the surf type. A scaling model based on the dissipated wave power and a surf similarity parameter is proposed and compared to measurements. The predictions show satisfactory agreement to the measurements.

  5. Admissibility of building cost subsidy in the power grid above the low voltage level

    International Nuclear Information System (INIS)

    Foerster, Sven

    2015-01-01

    Electricity networks are essential to the provision of electrical power to businesses and individuals. In particular for manufacturing businesses a connection to the grid above the low-voltage level is often useful. Network operators demand a subsidy for the new connection and for the change to a higher network level under the auspices of construction cost. The power network market above the low-voltage level is a natural monopoly. This leaves consumers looking for a connection to the power grid with no possibility to select among different network operators. Construction cost subsidies are not regulated by law above the low voltage level. The lack of legal regulation and the natural monopoly above the low-voltage level affect the balance of power between network operators and system users. The lawfulness of the construction cost subsidies, the prerequisites for their demand and a review of the calculation models (Leistungspreismodell, 2-Ebenen-Modell) as well as a proposal for a reform of this system form the subject of this work.

  6. Model for the techno-economic analysis of common work of wind power and CCGT power plant to offer constant level of power in the electricity market

    Science.gov (United States)

    Tomsic, Z.; Rajsl, I.; Filipovic, M.

    2017-11-01

    Wind power varies over time, mainly under the influence of meteorological fluctuations. The variations occur on all time scales. Understanding these variations and their predictability is of key importance for the integration and optimal utilization of wind in the power system. There are two major attributes of variable generation that notably impact the participation on power exchanges: Variability (the output of variable generation changes and resulting in fluctuations in the plant output on all time scales) and Uncertainty (the magnitude and timing of variable generation output is less predictable, wind power output has low levels of predictability). Because of these variability and uncertainty wind plants cannot participate to electricity market, especially to power exchanges. For this purpose, the paper presents techno-economic analysis of work of wind plants together with combined cycle gas turbine (CCGT) plant as support for offering continues power to electricity market. A model of wind farms and CCGT plant was developed in program PLEXOS based on real hourly input data and all characteristics of CCGT with especial analysis of techno-economic characteristics of different types of starts and stops of the plant. The Model analyzes the followings: costs of different start-stop characteristics (hot, warm, cold start-ups and shutdowns) and part load performance of CCGT. Besides the costs, the technical restrictions were considered such as start-up time depending on outage duration, minimum operation time, and minimum load or peaking capability. For calculation purposes, the following parameters are necessary to know in order to be able to economically evaluate changes in the start-up process: ramp up and down rate, time of start time reduction, fuel mass flow during start, electricity production during start, variable cost of start-up process, cost and charges for life time consumption for each start and start type, remuneration during start up time regarding

  7. A novel synthetic test system for thyristor level in the converter valve of HVDC power transmission

    Directory of Open Access Journals (Sweden)

    Liu Longchen

    2016-01-01

    Full Text Available The converter valve is the core equipment in the HVDC power transmission system, a+-nd its performance has a direct effect on the reliability, stability and efficiency of the whole power system. As the basic unit of HVDC converter valve, the thyristor level needs to be test routinely in order to grasp the state of the converter valve equipment. Therefore, it is urgent to develop a novel synthetic test system for the thyristor level with thyristor control unit (TCU. However, currently there is no specific test scheme for the thyristor level of HVDC converter valve. In this paper, the synthetic test principle, content and methods for the thyristor level with TCU are presented based on the analysis of the thyristor reverse recovery characteristic and the IEC technology standard. And a transient high-voltage pulse is applied to the thyristor level during its reverse recovery period in order to test the characteristics of thyristor level. Then, the synthetic test system for the thyristor level is applied to the converter valve test of ±800 kV HVDC power transmission project, and the practical test result verifies the reasonability and validity of the proposed synthetic test system.

  8. Sound for Health

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    From astronomy to biomedical sciences: music and sound as tools for scientific investigation Music and science are probably two of the most intrinsically linked disciplines in the spectrum of human knowledge. Science and technology have revolutionised the way artists work, interact, and create. The impact of innovative materials, new communication media, more powerful computers, and faster networks on the creative process is evident: we all can become artists in the digital era. What is less known, is that arts, and music in particular, are having a profound impact the way scientists operate, and think. From the early experiments by Kepler to the modern data sonification applications in medicine – sound and music are playing an increasingly crucial role in supporting science and driving innovation. In this talk. Dr. Domenico Vicinanza will be highlighting the complementarity and the natural synergy between music and science, with specific reference to biomedical sciences. Dr. Vicinanza will take t...

  9. Non-invasive liquid level and density gauge for nuclear power reactor pressure vessels

    International Nuclear Information System (INIS)

    Baratta, A.J.; Jester, W.A.; Kenney, E.S.; Mc Master, I.B.; Schultz, M.A.

    1987-01-01

    A method is described of non-invasively determining the liquid coolant level and density in a nuclear power reactor pressure vessel comprising the steps: positioning at least three neutron detector fission chambers externally of the reactor pressure vessel at multiple spaced positions along the side of the fuel core. One of the neutron detectors is positioned at the side near the bottom of the fuel core. The multiple spaced positions along the side remove any ambiguity as to whether the liquid level is decreasing or increasing: shielding the neutron detector fission chamber from thermal neutrons to avoid the noise associated therewith, and eliminating the effects of gamma radiation from the detected signals; monitoring the detected neutron level signals to determine to coolant liquid level and density in the nuclear power reactor pressure vessel

  10. Method and apparatus for reducing the power level in a nuclear reactor during temperature transient

    International Nuclear Information System (INIS)

    1980-01-01

    Devices for moving control rods with respect to reactor cores are described. Objects of the present invention include prevention of damage to a reactor and its surroundings during a temperature excursion and especially during a loss of flow accident and reduction of the power level in a nuclear reactor in a manner that is directly proportional to the increase in temperature of the primary coolant. Preferably the present invention provides a system that produces a negative temperature coefficient of reactivity in a liquid metal fast breeder reactor and is able to reduce the power level in a nuclear reactor after a loss of flow accident to less than 15 percent of full power without the intervention of any sensing devices or control rod actuators. (U.K.)

  11. Temporary core liquid level depression during cold-leg small-break LOCA effect of break size and power level

    International Nuclear Information System (INIS)

    Koizumi, Y.; Kumamaru, H.; Mimura, Y.; Kukita, Y.; Tasaka, K.

    1989-01-01

    Cold-leg small break LOCA experiments (0.5-10% break) were conducted at the large scale test facility (LSTF), a volumetrically-scaled (1/48) simulator of a PWR, of the ROSA-IV Program. When a break area was less than 2.5% of the scaled cold-leg flow area, the core liquid level was temporarily further depressed to the bottom elevation of the crossover leg during the loop seal clearing early in the transient only by the manometric pressure balance since no coolant remained in the upper portion of the primary system. When the break size was larger than 5%, the core liquid level was temporarily further depressed lower than the bottom elevation of the crossover leg during the loop seal clearing since coolant remained at the upper portion of the primary system; the steam generator (SG) U-tube upflow side and the SG inlet plenum, due to counter current flow limiting by updrafting steam while the coolant drained. The amount of coolant trapped there was dependent on the vapor velocity (core power); the larger the core power, the lower the minimum core liquid level. The RELAP5/MOD2 code reasonable predicted phenomena observed in the experiments. (orig./DG)

  12. The loudness of decaying impulsive sounds

    Science.gov (United States)

    Namba, S.; Hashimoto, T.; Rice, C. G.

    1987-08-01

    In the case of short duration sounds it is well known that temporal loudness summation occurs within a certain time period (i.e., critical duration), and a trade-off relationship is established between the sound intensity and the duration of the sound. Therefore, for the estimation of the loudness of brief sounds such as impulsive noise the temporal loudness summation must be considered. This paper deals with artificial impulsive sounds with a relatively short rise time and a long decay, as usually observed for actual impulsive sounds, and whether the loudness of an impulsive sound is determined by the peak level of the sound or by the total energy of the sound including the decaying part. L AX in ISO 1996, which is the single event exposure level, is chosen as an energy index of the sound in this paper. It is probable, however, that the time varying pattern of the sound or auditory after effect has an effect on the loudness of impulsive sounds. Such effects, however, are not reflected either in L AX or in the peak level measurement. Accordingly additional experiments have been carried out to examine the temporal characteristics of the hearing mechanism in relation to the loudness of impulsive sounds. As a result, it seems that L AX is a good measure of the loudness of impulsive sounds which are not too short, but when the duration of the sound is less than 60 ms the contribution of the auditory after-effect on the loudness needs to be taken into consideration. No relation could be found between the peak level and the loudness of impulsive sounds.

  13. Evaluation of safety issues on newly regulated nuclear power plant by tsunami-level 1 PRA

    International Nuclear Information System (INIS)

    Tsuji, Yutaro; Miwa, Shuichiro; Mori, Michitsugu

    2014-01-01

    The tsunami caused by the Great East Japan Earthquake triggered severe accidents involving the units 1 to 4 at the Fukushima Dai-ichi nuclear power station (NPS). In order to re-operate existing nuclear power plants it should be necessary to reduce the core damage frequency on risk by tsunami. In this work, effects of the off-site power supply installation on resuming operation of nuclear power plants were investigated by utilizing the Tsunami-Level 1 Probability Risk Assessment (PRA). Unit 2 of the Onagawa nuclear power station, which resembled units 2 and 3 of Fukushima Dai-ichi, was selected for PRA. First, event-tree was created for the units of the Onagawa nuclear power station with the safety systems such as Emergency Core Cooling System (ECCS), investigating the plant situation at the time of the earthquake and tsunami occurrences. It was assumed that the magnitude of the tsunami was equivalent to the Great East Japan Earthquake. The accident-analytical progression-time was 36 hours, determined from the core-damage occurrence of the unit 3 of Fukushima Dai-ichi nuclear power station. Failure probabilities were calculated by the fault tree, which was created from the elements listed in the event tree. For the calculation, failure rates reported by the NUCIA (NUClear Information Archives) were primarily utilized. Then, obtained failure probabilities were embedded to the event tree. Core damage probabilities were evaluated by calculating success and failure rates for each accidental progression and scenarios. Restoration of the failed equipment and machineries was not considered in the analysis. Installation of the power supply vehicles at the nuclear power plant site reduced the core damage probability from 2.58×10 -6 to 8.56×10 -7 . However, continued addition of the power supply vehicles could not lower the core damage probability further more. In the case of Unit 2 of Onagawa nuclear power station, there could be a limit to lower the core damage

  14. A high-level power model for MPSoC on FPGA

    NARCIS (Netherlands)

    Piscitelli, R.; Pimentel, A.D.

    2012-01-01

    This paper presents a framework for high-level power estimation of multiprocessor systems-on-chip (MPSoC) architectures on FPGA. The technique is based on abstract execution profiles, called event signatures. As a result, it is capable of achieving good evaluation performance, thereby making the

  15. Empirical LTE Smartphone Power Model with DRX Operation for System Level Simulations

    DEFF Research Database (Denmark)

    Lauridsen, Mads; Noël, Laurent; Mogensen, Preben

    2013-01-01

    An LTE smartphone power model is presented to enable academia and industry to evaluate users’ battery life on system level. The model is based on empirical measurements on a smartphone using a second generation LTE chipset, and the model includes functions of receive and transmit data rates...

  16. The Evolution of Power System Planning with High Levels of Variable Renewable Generation

    Energy Technology Data Exchange (ETDEWEB)

    Katz, Jessica [National Renewable Energy Lab. (NREL), Golden, CO (United States); Milligan, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid. This document, part of the Greening the Grid introduces the evolution of power system planning with high levels of variable renewable generation.

  17. Improving Sound Systems by Electrical Means

    DEFF Research Database (Denmark)

    Schneider, Henrik

    an intelligent approach to estimate the power requirements to obtain a size and cost reduction. The greatest challenge was to develop an analyzing tool to estimate the worst case power scenario versus time for a given loudspeaker application. Models including the influence of the enclosure and the most critical......The availability and flexibility of audio services on various digital platforms have created a high demand for a large range of sound systems. The fundamental components of sound systems such as docking stations, sound bars and wireless mobile speakers consists of a power supply, amplifiers...... was considered, the power requirement of the power supply could be relaxed if the acoustical power requirement was known, the total sound system efficiency could be optimized which would properly require a radical design change for all the components, communication between the components could lead...

  18. Improving the Sound Pressure Level of Two-Dimensional Audio Actuators by Coating Single-Walled Carbon Nanotubes on Piezoelectric Films.

    Science.gov (United States)

    Um, Keehong

    2015-10-01

    As devices for amplifying or transforming electronic signals into audible signals through electromechanical operations, acoustic actuators in the form of loudspeakers are usually solid structures in three dimensional space. Recently there has been increasing demand for mobile electronic devices, such as mobile phones, to become smaller, thinner, and lighter. In contrast to a three dimensional audio system with magnets, we have invented a new type of flexible two dimensional device by utilizing the reverse piezoelectric effect in certain piezoelectric materials. Crystalline piezoelectric materials show electromechanical interaction between the mechanical state and the electrically-charged state. The piezoelectric effect is a reversible process in that materials exhibiting the direct piezoelectric effect (the internal generation of electrical charge resulting from an applied mechanical force) also exhibit the reverse piezoelectric effect (the internal generation of a mechanical strain resulting from an applied electrical field). We have adopted the plasma surface treatment in order to put coating materials on the surface of piezoelectric film. We compared two kinds of coating material, indium tin oxide and single-walled carbon nanotube, and found that single-walled carbon nanotube shows better performance. The results showed improvement of output power in a wider range of operating frequency; for the surface resistance of 0.5 kΩ/square, the single-walled CNT shows the range of operating frequency to be 0.75-17.5 kHz, but ITO shows 2.5-13.4 kHz. For the surface resistance of 1 kΩ/square, single-walled CNT shows the range of operating frequency to be 0.81-17 kHz, but ITO shows it cannot generate audible sound.

  19. Studies of power exhaust and divertor design for a 1.5 GW-level fusion power DEMO

    Science.gov (United States)

    Asakura, N.; Hoshino, K.; Suzuki, S.; Tokunaga, S.; Someya, Y.; Utoh, H.; Kudo, H.; Sakamoto, Y.; Hiwatari, R.; Tobita, K.; Shimizu, K.; Ezato, K.; Seki, Y.; Ohno, N.; Ueda, Y.; Joint Special TeamDEMO Design

    2017-12-01

    Power exhaust to the divertor and the conceptual design have been investigated for a steady-state DEMO in Japan with 1.5 GW-level fusion power and the major radius of 8.5 m, where the plasma parameters were revised appropriate for the impurity seeding scenario. A system code survey for the Ar impurity seeding suggested the volume-averaged density, impurity concentration and exhaust power from the main plasma of {{P}sep ~ }   =  205-285 MW. The divertor plasma simulation (SONIC) was performed in the divertor leg length of 1.6 m with the fixed exhaust power to the edge of {{P}out}   =  250 MW and the total radiation fraction at the edge, SOL and divertor ({{P}rad}/{{P}out}   =  0.8), as a first step to investigate appropriate design of the divertor size and geometry. At the outer target, partial detachment was produced near the strike-point, and the peak heat load ({{q}target} ) at the attached region was reduced to ~5 MW m-2 with appropriate fuel and impurity puff rates. At the inner divertor target, full detachment of ion flux was produced and the peak {{q}target} was less than 10 MW m-2 mostly due to the surface-recombination. These results showed a power exhaust scenario and the divertor design concept. An integrated design of the water-cooling heat sink for the long leg divertor was proposed. Cu-ally (CuCrZr) cooling pipe was applicable as the heat sink to handle the high heat flux near the strike-point, where displacements per atom rate was estimated to be 0.5-1.5 per year by neutronics calculation. An arrangement of the coolant rooting for Cu-alloy and Reduced Activation Ferritic Martensitic (RAFM) steel (F82H) pipes in a divertor cassette was investigated, and the heat transport analysis of the W-monoblock and Cu-alloy pipe under the peak {{q}target} of 10 MWm-2 and nuclear heating was performed. The maximum temperatures on the W-surface and Cu-alloy pipe were 1021 and 331 °C. Heat flux of 16 MW m-2 was distributed in the major part

  20. Erratum: Correction to Table 3, in: Equivalent threshold sound pressure levels (ETSPL) for Sennheiser HDA 280 supra-aural audiometric earphones in the frequency range 125 Hz to 8000 Hz (International Journal of Audiology (2009) 48 (271-276))

    DEFF Research Database (Denmark)

    Poulsen, Torben

    2014-01-01

    The main results in Poulsen & Oakley (2009) are given as the equivalent threshold sound pressure level, ETSPL, measured in an acoustic coupler specifi ed in IEC 60318-3. These results are all correct. The ETSPL values for the ear simulator specifi ed in IEC 60318-1 were calculated from acoustic l...

  1. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Engineering Test Report: AMSU-A2 METSAT Instrument (S/N 108) Acceptance Level Vibration Tests of Dec 1999/Jan 2000 (S/O 784077, OC-454)

    Science.gov (United States)

    Heffner, R.

    2000-01-01

    This is the Engineering Test Report, AMSU-A2 METSAT Instrument (S/N 108) Acceptance Level Vibration Test of Dec 1999/Jan 2000 (S/O 784077, OC-454), for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).

  2. A Security Level Classification Method for Power Systems under N-1 Contingency

    Directory of Open Access Journals (Sweden)

    Zhigang Lu

    2017-12-01

    Full Text Available Security assessment is crucial for the reliable and secure operation of power systems. This paper proposes a security level classification (SLC method to analyze the security level of power systems both qualitatively and quantitatively. In this SLC method, security levels are graded according to a comprehensive safety index (CSI, which is defined by integrating the system margin index (SMI and load entropy. The SMI depends on the operating load and the total supply capacity (TSC under N-1 contingency, and the load entropy reflects the heterogeneity of load distribution calculated from entropy theory. In order to calculate the TSC under N-1 contingency considering both of the computational accuracy and speed, the TSC is converted into an extended conic quadratic programming (ECQP model. In addition, the load boundary vector (LBV model is established to obtain the capacity limit of each load bus, and thus detect potential risks of power systems. Finally, two modified practical power systems and the IEEE 118-bus test system are studied to validate the feasibility of the proposed SLC method.

  3. Neural Network with Local Memory for Nuclear Reactor Power Level Control

    International Nuclear Information System (INIS)

    Uluyol, Oender; Ragheb, Magdi; Tsoukalas, Lefteri

    2001-01-01

    A methodology is introduced for a neural network with local memory called a multilayered local output gamma feedback (LOGF) neural network within the paradigm of locally-recurrent globally-feedforward neural networks. It appears to be well-suited for the identification, prediction, and control tasks in highly dynamic systems; it allows for the presentation of different timescales through incorporation of a gamma memory. A learning algorithm based on the backpropagation-through-time approach is derived. The spatial and temporal weights of the network are iteratively optimized for a given problem using the derived learning algorithm. As a demonstration of the methodology, it is applied to the task of power level control of a nuclear reactor at different fuel cycle conditions. The results demonstrate that the LOGF neural network controller outperforms the classical as well as the state feedback-assisted classical controllers for reactor power level control by showing a better tracking of the demand power, improving the fuel and exit temperature responses, and by performing robustly in different fuel cycle and power level conditions

  4. Computer-based control of nuclear power information systems at international level

    International Nuclear Information System (INIS)

    Boniface, Ekechukwu; Okonkwo, Obi

    2011-01-01

    In most highly industrialized countries of the world information plays major role in anti-nuclear campaign. Information and discussions on nuclear power need critical and objective analysis before the structured information presentation to the public to avoid bias anti-nuclear information on one side and neglect of great risk in nuclear power. This research is developing a computer-based information system for the control of nuclear power at international level. The system is to provide easy and fast information highways for the followings: (1) Low Regulatory dose and activity limit as level of high danger for individuals and public. (2) Provision of relevant technical or scientific education among the information carriers in the nuclear power countries. The research is on fact oriented investigation about radioactivity. It also deals with fact oriented education about nuclear accidents and safety. A standard procedure for dissemination of latest findings using technical and scientific experts in nuclear technology is developed. The information highway clearly analyzes the factual information about radiation risk and nuclear energy. Radiation cannot be removed from our environment. The necessity of radiation utilizations defines nuclear energy as two-edge sword. It is therefore, possible to use computer-based information system in projecting and dissemination of expert knowledge about nuclear technology positively and also to use it in directing the public on the safety and control of the nuclear energy. The computer-based information highway for nuclear energy technology is to assist in scientific research and technological development at international level. (author)

  5. Comparative study of the base activity levels of the Spanish continental nuclear power stations

    International Nuclear Information System (INIS)

    Gregorides de los Santos y Perez-Minguez, A.M.

    1980-01-01

    In this work the pre-operational activity levels of the sites of some Spanish nuclear power stations are discussed. These power stations are located near the Tagus and Ebro river basins. A report of the communities investigated is made. The total alpha and beta activity as well as the long half life activity has been researched there. The importance of this question is obvious for it gives a regional average of the base activity in the basins of these two big Spanish rivers [fr

  6. Output Feedback Dissipation Control for the Power-Level of Modular High-Temperature Gas-Cooled Reactors

    OpenAIRE

    Dong, Zhe

    2011-01-01

    Because of its strong inherent safety features and the high outlet temperature, the modular high temperature gas-cooled nuclear reactor (MHTGR) is the chosen technology for a new generation of nuclear power plants. Such power plants are being considered for industrial applications with a wide range of power levels, thus power-level regulation is very important for their efficient and stable operation. Exploiting the large scale asymptotic closed-loop stability provided by nonlinear controller...

  7. Photovoltaic Shading Testbed for Module-Level Power Electronics: 2016 Performance Data Update

    Energy Technology Data Exchange (ETDEWEB)

    Deline, Chris [National Renewable Energy Lab. (NREL), Golden, CO (United States); Meydbray, Jenya [PV Evolution Labs (PVEL), Davis, CA (United States); Donovan, Matt [PV Evolution Labs (PVEL), Davis, CA (United States)

    2016-09-01

    The 2012 NREL report 'Photovoltaic Shading Testbed for Module-Level Power Electronics' provides a standard methodology for estimating the performance benefit of distributed power electronics under partial shading conditions. Since the release of the report, experiments have been conducted for a number of products and for different system configurations. Drawing from these experiences, updates to the test and analysis methods are recommended. Proposed changes in data processing have the benefit of reducing the sensitivity to measurement errors and weather variability, as well as bringing the updated performance score in line with measured and simulated values of the shade recovery benefit of distributed PV power electronics. Also, due to the emergence of new technologies including sub-module embedded power electronics, the shading method has been extended to include power electronics that operate at a finer granularity than the module level. An update to the method is proposed to account for these emerging technologies that respond to shading differently than module-level devices. The partial shading test remains a repeatable test procedure that attempts to simulate shading situations as would be experienced by typical residential or commercial rooftop photovoltaic (PV) systems. Performance data for multiple products tested using this method are discussed, based on equipment from Enphase, Solar Edge, Maxim Integrated and SMA. In general, the annual recovery of shading losses from the module-level electronics evaluated is 25-35%, with the major difference between different trials being related to the number of parallel strings in the test installation rather than differences between the equipment tested. Appendix D data has been added in this update.

  8. Steady-state plant model to predict hydrogen levels in power plant components

    Science.gov (United States)

    Glatzmaier, Greg C.; Cable, Robert; Newmarker, Marc

    2017-06-01

    The National Renewable Energy Laboratory (NREL) and Acciona Energy North America developed a full-plant steady-state computational model that estimates levels of hydrogen in parabolic trough power plant components. The model estimated dissolved hydrogen concentrations in the circulating heat transfer fluid (HTF), and corresponding partial pressures within each component. Additionally for collector field receivers, the model estimated hydrogen pressure in the receiver annuli. The model was developed to estimate long-term equilibrium hydrogen levels in power plant components, and to predict the benefit of hydrogen mitigation strategies for commercial power plants. Specifically, the model predicted reductions in hydrogen levels within the circulating HTF that result from purging hydrogen from the power plant expansion tanks at a specified target rate. Our model predicted hydrogen partial pressures from 8.3 mbar to 9.6 mbar in the power plant components when no mitigation treatment was employed at the expansion tanks. Hydrogen pressures in the receiver annuli were 8.3 to 8.4 mbar. When hydrogen partial pressure was reduced to 0.001 mbar in the expansion tanks, hydrogen pressures in the receiver annuli fell to a range of 0.001 mbar to 0.02 mbar. When hydrogen partial pressure was reduced to 0.3 mbar in the expansion tanks, hydrogen pressures in the receiver annuli fell to a range of 0.25 mbar to 0.28 mbar. Our results show that controlling hydrogen partial pressure in the expansion tanks allows us to reduce and maintain hydrogen pressures in the receiver annuli to any practical level.

  9. Steady-State Plant Model to Predict Hydroden Levels in Power Plant Components

    Energy Technology Data Exchange (ETDEWEB)

    Glatzmaier, Greg C.; Cable, Robert; Newmarker, Marc

    2017-06-27

    The National Renewable Energy Laboratory (NREL) and Acciona Energy North America developed a full-plant steady-state computational model that estimates levels of hydrogen in parabolic trough power plant components. The model estimated dissolved hydrogen concentrations in the circulating heat transfer fluid (HTF), and corresponding partial pressures within each component. Additionally for collector field receivers, the model estimated hydrogen pressure in the receiver annuli. The model was developed to estimate long-term equilibrium hydrogen levels in power plant components, and to predict the benefit of hydrogen mitigation strategies for commercial power plants. Specifically, the model predicted reductions in hydrogen levels within the circulating HTF that result from purging hydrogen from the power plant expansion tanks at a specified target rate. Our model predicted hydrogen partial pressures from 8.3 mbar to 9.6 mbar in the power plant components when no mitigation treatment was employed at the expansion tanks. Hydrogen pressures in the receiver annuli were 8.3 to 8.4 mbar. When hydrogen partial pressure was reduced to 0.001 mbar in the expansion tanks, hydrogen pressures in the receiver annuli fell to a range of 0.001 mbar to 0.02 mbar. When hydrogen partial pressure was reduced to 0.3 mbar in the expansion tanks, hydrogen pressures in the receiver annuli fell to a range of 0.25 mbar to 0.28 mbar. Our results show that controlling hydrogen partial pressure in the expansion tanks allows us to reduce and maintain hydrogen pressures in the receiver annuli to any practical level.

  10. Sound Search Engine Concept

    DEFF Research Database (Denmark)

    2006-01-01

    Sound search is provided by the major search engines, however, indexing is text based, not sound based. We will establish a dedicated sound search services with based on sound feature indexing. The current demo shows the concept of the sound search engine. The first engine will be realased June...

  11. Power optimization of digital baseband WCDMA receiver components on algorithmic and architectural level

    Science.gov (United States)

    Schämann, M.; Bücker, M.; Hessel, S.; Langmann, U.

    2008-05-01

    High data rates combined with high mobility represent a challenge for the design of cellular devices. Advanced algorithms are required which result in higher complexity, more chip area and increased power consumption. However, this contrasts to the limited power supply of mobile devices. This presentation discusses the application of an HSDPA receiver which has been optimized regarding power consumption with the focus on the algorithmic and architectural level. On algorithmic level the Rake combiner, Prefilter-Rake equalizer and MMSE equalizer are compared regarding their BER performance. Both equalizer approaches provide a significant increase of performance for high data rates compared to the Rake combiner which is commonly used for lower data rates. For both equalizer approaches several adaptive algorithms are available which differ in complexity and convergence properties. To identify the algorithm which achieves the required performance with the lowest power consumption the algorithms have been investigated using SystemC models regarding their performance and arithmetic complexity. Additionally, for the Prefilter Rake equalizer the power estimations of a modified Griffith (LMS) and a Levinson (RLS) algorithm have been compared with the tool ORINOCO supplied by ChipVision. The accuracy of this tool has been verified with a scalable architecture of the UMTS channel estimation described both in SystemC and VHDL targeting a 130 nm CMOS standard cell library. An architecture combining all three approaches combined with an adaptive control unit is presented. The control unit monitors the current condition of the propagation channel and adjusts parameters for the receiver like filter size and oversampling ratio to minimize the power consumption while maintaining the required performance. The optimization strategies result in a reduction of the number of arithmetic operations up to 70% for single components which leads to an estimated power reduction of up to 40

  12. Power optimization of digital baseband WCDMA receiver components on algorithmic and architectural level

    Directory of Open Access Journals (Sweden)

    M. Schämann

    2008-05-01

    Full Text Available High data rates combined with high mobility represent a challenge for the design of cellular devices. Advanced algorithms are required which result in higher complexity, more chip area and increased power consumption. However, this contrasts to the limited power supply of mobile devices.

    This presentation discusses the application of an HSDPA receiver which has been optimized regarding power consumption with the focus on the algorithmic and architectural level. On algorithmic level the Rake combiner, Prefilter-Rake equalizer and MMSE equalizer are compared regarding their BER performance. Both equalizer approaches provide a significant increase of performance for high data rates compared to the Rake combiner which is commonly used for lower data rates. For both equalizer approaches several adaptive algorithms are available which differ in complexity and convergence properties. To identify the algorithm which achieves the required performance with the lowest power consumption the algorithms have been investigated using SystemC models regarding their performance and arithmetic complexity. Additionally, for the Prefilter Rake equalizer the power estimations of a modified Griffith (LMS and a Levinson (RLS algorithm have been compared with the tool ORINOCO supplied by ChipVision. The accuracy of this tool has been verified with a scalable architecture of the UMTS channel estimation described both in SystemC and VHDL targeting a 130 nm CMOS standard cell library.

    An architecture combining all three approaches combined with an adaptive control unit is presented. The control unit monitors the current condition of the propagation channel and adjusts parameters for the receiver like filter size and oversampling ratio to minimize the power consumption while maintaining the required performance. The optimization strategies result in a reduction of the number of arithmetic operations up to 70% for single components which leads to an

  13. Effect of Low-Level Laser Stimulation on EEG Power in Normal Subjects with Closed Eyes

    Directory of Open Access Journals (Sweden)

    Jih-Huah Wu

    2013-01-01

    Full Text Available In a previous study, we found that the low-level laser (LLL stimulation at the palm with a frequency of 10 Hz was able to induce significant brain activation in normal subjects with opened eyes. However, the electroencephalography (EEG changes to LLL stimulation in subjects with closed eyes have not been studied. In the present study, the laser array stimulator was applied to deliver insensible laser stimulations to the palm of the tested subjects with closed eyes (the laser group. The EEG activities before, during, and after the laser stimulation were collected. The EEG amplitude powers of each EEG frequency band at 19 locations were calculated. These power data were then analyzed by SPSS software using repeated-measure ANOVAs and appropriate posthoc tests. We found a pronounced decrease in the EEG power in alpha-bandwidth during laser simulation and then less decrease in the EEG power in delta-bandwidth in normal subjects with laser stimulation. The EEG power in beta-bandwidth in the right occipital area also decreased significantly in the laser group. We suggest that LLL stimulation might be conducive to falling into sleep in patients with sleep problems.

  14. Power spectrum of nuclear spectra with missing levels and mixed symmetries

    Energy Technology Data Exchange (ETDEWEB)

    Molina, R.A. [Max-Planck-Institut fuer Physik Komplexer Systeme, Noethnitzer Str. 38, D-01187 Dresden (Germany) and Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006 Madrid (Spain)]. E-mail: molina@iem.cfmac.csic.es; Retamosa, J. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Munoz, L. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Relano, A. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006 Madrid (Spain); Faleiro, E. [Departamento de Fisica Aplicada, Universidad Politecnica de Madrid, E-28012 (Spain)

    2007-01-04

    Sequences of energy levels in nuclei are often plagued with missing levels whose number and position are unknown. It is also quite usual that all the quantum numbers of certain levels cannot be experimentally determined, and thus levels of different symmetries are mixed in the same sequence. The analysis of these imperfect spectra (from the point of view of spectral statistics) is unavoidable if one wants to extract some statistical information. The power spectrum of the {delta}{sub q} statistic has emerged in recent years as an important tool for the study of quantum chaos and spectral statistics. We derive analytical expressions for the observed power spectrum in terms of the fraction of observed levels and the number of mixed sequences. These expressions are tested with large shell model spectra simulating realistic experimental situations. A good estimation of the number of mixed symmetries and the fraction of missing levels is obtained by means of a least-squares fit in a wide set of different situations.

  15. Synergistic Success: The Power of Mentorship and Reaching the Senior Levels of the U.S. Army

    Science.gov (United States)

    2017-06-09

    SYNERGISTIC SUCCESS: THE POWER OF MENTORSHIP AND REACHING THE SENIOR LEVELS OF THE U.S. ARMY A thesis presented to the Faculty of...To) AUG 2016 – JUNE 2017 4. TITLE AND SUBTITLE Synergistic Success: The Power of Mentorship and Reaching the Senior Levels of the U.S. Army 5a...Synergistic Success: The Power of Mentorship and Reaching the Senior Levels of the U.S. Army Approved by: , Thesis Committee Chair Jack D

  16. NASA Space Sounds API

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has released a series of space sounds via sound cloud. We have abstracted away some of the hassle in accessing these sounds, so that developers can play with...

  17. A Transformer-less Partial Power Boost Converter for PV Applications Using a Three-Level Switching Cell

    Energy Technology Data Exchange (ETDEWEB)

    Agamy, Mohammed; Harfman-Todorovic, Maja; Elasser, Ahmed; Essakiappan, Somasundaram

    2013-03-01

    Photovoltaic architectures with distributed power electronics provide many advantages in terms of energy yield as well as system level optimization. As the power level of the solar farm increases it becomes more beneficial to increase the dc collection network voltage, which requires the use of power devices with higher voltage ratings, and thus making the design of efficient, low cost, distributed power converters more challenging. In this paper a simple partial power converter topology is proposed. The topology is implemented using a three-level switching cell, which allows the use of semiconductor devices with lower voltage rating; thus improving design and performance and reducing converter cost. This makes the converters suitable for use for medium to high power applications where dc-link voltages of 600V~1kV may be needed without the need for high voltage devices. Converter operation and experimental results are presented for two partial power circuit variants using three-level switching cells.

  18. Application of PSA to Assess the Safety Level of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Berg, H. P.; Goertz, R.

    2000-01-01

    This paper reviews the application of PSA in German nuclear power plant regulation. From a fundamental point of view, it has to be mentioned that as stipulated in the corresponding requirements, regulatory decision making in Germany is primarily based on deterministic analyses and evaluations. Therefore, PSA is not used as a stand alone but as a supplementary basis. In this context PSA has developed a valuable tool with continuously growing importance. Level 1+ PSAs are now elaborated for all German nuclear power plants in operation, most of them are already reviewed by the competent supervisory authority and its experts. Current research activities on the federal level primarily concentrate on the further development of the methodology in the areas human factor, common cause failures, accident management measures and reduction of uncertainties in methods and data. (author)

  19. Habit, custom, and power: a multi-level theory of population health.

    Science.gov (United States)

    Zimmerman, Frederick J

    2013-03-01

    In multi-level theory, individual behavior flows from cognitive habits, either directly through social referencing, rules of thumb, or automatic behaviors; or indirectly through the shaping of rationality itself by framing or heuristics. Although behavior does not arise from individually rational optimization, it generally appears to be rational, because the cognitive habits that guide behavior evolve toward optimality. However, power imbalances shaped by particular social, political, and economic structures can distort this evolution, leading to individual behavior that fails to maximize individual or social well-being. Replacing the dominant rational-choice paradigm with a multi-level theoretical paradigm involving habit, custom, and power will enable public health to engage in rigorous new areas of research. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. POPCYCLE: a computer code for calculating nuclear and fossil plant levelized life-cycle power costs

    International Nuclear Information System (INIS)

    Hardie, R.W.

    1982-02-01

    POPCYCLE, a computer code designed to calculate levelized life-cycle power costs for nuclear and fossil electrical generating plants is described. Included are (1) derivations of the equations and a discussion of the methodology used by POPCYCLE, (2) a description of the input required by the code, (3) a listing of the input for a sample case, and (4) the output for a sample case

  1. Nonlinear Adaptive Dynamic Output-Feedback Power-Level Control of Nuclear Heating Reactors

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2013-01-01

    Full Text Available Due to the high safety performance of small nuclear reactors, there is a promising future for small reactors. Nuclear heating reactor (NHR is a small reactor that has many advanced safety features such as the integrated arrangement, natural circulation at any power levels, self-pressurization, hydraulic control rod driving, and passive residual heating removing and can be applied to the fields of district heating, seawater desalination, and electricity production. Since the NHR dynamics has strong nonlinearity and uncertainty, it is meaningful to develop the nonlinear adaptive power-level control technique. From the idea of physically based control design method, a novel nonlinear adaptive power-level control is given for the NHR in this paper. It is theoretically proved that this newly built controller does not only provide globally asymptotic closed-loop stability but is also adaptive to the system uncertainty. Numerical simulation results show the feasibility of this controller and the relationship between the performance and controller parameters.

  2. Maximum Power Point Tracking With Improved Incremental Conductance Method for Fast Changing Solar Irradiation Level

    Science.gov (United States)

    >Tey Kok Soon, Saad Mekhilef,

    2013-06-01

    This paper proposed an improved incremental conductance method to track the Maximum Power Point (MPP) for PV Panel under fast changing solar irradiation. When there is increment in solar irradiation level, the conventional incremental conductance method is confused and responses incorrectly. The proposed method response correctly and there is no steady state oscillation compared to the conventional method. Matlab simulation is carried out for both the improved and conventional incremental conductance method under fast changing solar irradiation level. The simulation results showed the system able to track the MPP faster than the conventional method.

  3. Differentiated influences of benefit and risk perceptions on nuclear power acceptance according to acceptance levels. Evidence from Korea

    International Nuclear Information System (INIS)

    Roh, Seungkook; Lee Jinwon

    2017-01-01

    The perceived benefit and risk of nuclear power generation have received considerable attention as determinants of the public's nuclear power acceptance. However, the contingency of the relative importance of these benefit and risk has been less explored. Using Korea as an example, this study explores the possibility that the relative importance of perceived benefit and risk on nuclear power acceptance depends on acceptance levels. Our results from latent class analysis and multinomial probit show that, in determining whether an individual shows a moderate level of nuclear power acceptance rather than a low level, perceived risk plays a dominant role compared to perceived benefit; however, regarding whether he/she shows a high level of nuclear power acceptance rather than a moderate level, this relative importance is reversed. These results carry practical implications for risk governance of nuclear power, particularly with regard to communication with the public. (author)

  4. Sound Ecologies

    Directory of Open Access Journals (Sweden)

    Michelle Duffy

    2010-02-01

    Full Text Available Discussions about what constitutes ‘the rural’ invariably focus on notions of spatial location – of inhabiting spaces apart from that of the metropolitan. Deeply embedded in our images of what it means to be Australian, nonetheless our intellectual framing of ‘the rural’ as something outback and beyond has significant implications for our relations with these spaces. The relatively recent phenomenon of sea- and tree-changes has struck many unawares, and not simply because a good latté is so hard to find. Although a frivolous remark, such an apparent lack does shift our focus to a bodily scale of the rural; how is rural place re/made through our experiences of it? This article originates out of on-going research that explores the practice of listening and sound and the ways in which the body can draw attention to the intuitive, emotional, and psychoanalytical processes of subjectivity and place-making. Drawing on Nigel Thrift’s concept of an ecology of place, I suggest that contemporary heightened concerns with regards to loss and lack in rural Australia has led to a nascent emotional economy – one in which individual and intimate connections to the rural require a rethinking of how we live community and belonging. In such a terrain, what does it mean to be rural?

  5. Sound ecologies

    Directory of Open Access Journals (Sweden)

    Duffy, Michelle

    2010-01-01

    Full Text Available Discussions about what constitutes ‘the rural’ invariably focus on notions of spatial location – of inhabiting spaces apart from that of the metropolitan. Deeply embedded in our images of what it means to be Australian, nonetheless our intellectual framing of ‘the rural’ as something outback and beyond has significant implications for our relations with these spaces. The relatively recent phenomenon of sea- and tree-changes has struck many unawares, and not simply because a good latté is so hard to find. Although a frivolous remark, such an apparent lack does shift our focus to a bodily scale of the rural; how is rural place re/made through our experiences of it? This article originates out of on-going research that explores the practice of listening and sound and the ways in which the body can draw attention to the intuitive, emotional, and psychoanalytical processes of subjectivity and place-making. Drawing on Nigel Thrift’s concept of an ecology of place, I suggest that contemporary heightened concerns with regards to loss and lack in rural Australia has led to a nascent emotional economy – one in which individual and intimate connections to the rural require a rethinking of how we live community and belonging. In such a terrain, what does it mean to be rural?

  6. Three integrated photovoltaic/sound barrier power plants. Construction and operational experience; Drei integrierte PV-Schallschutz Versuchsfelder. Bau und Erprobung

    Energy Technology Data Exchange (ETDEWEB)

    Nordmann, T.; Froelich, A.; Clavadetscher, L.

    2002-07-01

    After an international ideas competition by TNC Switzerland and Germany in 1996, six companies where given the opportunity to construct a prototype of their newly developed integrated PV-sound barrier concepts. The main goal was to develop highly integrated concepts, allowing the reduction of PV sound barrier systems costs, as well as the demonstration of specific concepts for different noise situations. This project is strongly correlated with a German project. Three of the concepts of the competition are demonstrated along a highway near Munich, constructed in 1997. The three Swiss installations had to be constructed at different locations, reflecting three typical situations for sound barriers. The first Swiss installation was the world first Bi-facial PV-sound barrier. It was built on a highway bridge at Wallisellen-Aubrugg in 1997. The operational experience of the installation is positive. But due to the different efficiencies of the two cell sides, its specific yield lies somewhat behind a conventional PV installation. The second Swiss plant was finished in autumn 1998. The 'zig-zag' construction is situated along the railway line at Wallisellen in a densely inhabited area with some local shadowing. Its performance and its specific yield is comparatively low due to a combination of several reasons (geometry of the concept, inverter, high module temperature, local shadows). The third installation was constructed along the motor way A1 at Bruettisellen in 1999. Its vertical panels are equipped with amorphous modules. The report show, that the performance of the system is reasonable, but the mechanical construction has to be improved. A small trial field with cells directly laminated onto the steel panel, also installed at Bruettisellen, could be the key development for this concept. This final report includes the evaluation and comparison of the monitored data in the past 24 months of operation. (author)

  7. Final disposal of high-level waste from nuclear power plants

    International Nuclear Information System (INIS)

    1979-05-01

    A report on the possibilities of high-level radioactive waste disposal is presented by a working group appointed by the Danish Academy of Technical Sciences which consists of specialists in nuclear power, corrosion, health physics, chemistry, geology, physics, and zoology. If nuclear power is introduced in Denmark five nuclear power plants with a total installed power of about 5000 MW are expected to be established. Dependent on the handling procedures the volume of the high-level wastes will be between 10 and 50 cubic meters yearly. As the amount of wastes that would be produced in Danish nuclear power plants will be small compared to the amount from other countries, it is natural to try to solve a Danish waste problem through an arrangement on waste disposal with a foreign plant. Also, for economic and technical reasons this solution would be the best, and the entering into a satisfactory agreement should therefore be given high priority. However, it is not possible to know for sure that such an agreement could be reached, and it is therefore necessary to evaluate the possibilities for geologic waste disposal in Denmark. It is concluded that without doubt several geologic formations in the Danish deeper underground are suitable for waste disposal. A main problem is to find a formation which can prove to be isolated from the biosphere for many millennia. It is recommended that geological formations be studied in detail and that some locations suitable for waste disposal should be selected in order that they can be reserved for this purpose. (B.P.)

  8. Sound localization and occupational noise

    Directory of Open Access Journals (Sweden)

    Pedro de Lemos Menezes

    2014-02-01

    Full Text Available OBJECTIVE: The aim of this study was to determine the effects of occupational noise on sound localization in different spatial planes and frequencies among normal hearing firefighters. METHOD: A total of 29 adults with pure-tone hearing thresholds below 25 dB took part in the study. The participants were divided into a group of 19 firefighters exposed to occupational noise and a control group of 10 adults who were not exposed to such noise. All subjects were assigned a sound localization task involving 117 stimuli from 13 sound sources that were spatially distributed in horizontal, vertical, midsagittal and transverse planes. The three stimuli, which were square waves with fundamental frequencies of 500, 2,000 and 4,000 Hz, were presented at a sound level of 70 dB and were randomly repeated three times from each sound source. The angle between the speaker's axis in the same plane was 45°, and the distance to the subject was 1 m. RESULT: The results demonstrate that the sound localization ability of the firefighters was significantly lower (p<0.01 than that of the control group. CONCLUSION: Exposure to occupational noise, even when not resulting in hearing loss, may lead to a diminished ability to locate a sound source.

  9. AVE/VAS 4: 25-mb sounding data

    Science.gov (United States)

    Sienkiewicz, M. E.

    1983-01-01

    The rawinsonde sounding program is described and tabulated data at 25 mb intervals for the 24 stations and 14 special stations participating in the experiment is presented. Sounding were taken at 3 hr intervals. An additional sounding was taken at the normal synoptic observation time. Some soundings were computed from raw ordinate data, while others were interpolated from significant level data.

  10. Summary of the environmental conditions that change the sound levels in wind turbines; Synthese des conditions environnementales modifiant les niveaux sonores de bruit des eoliennes

    Energy Technology Data Exchange (ETDEWEB)

    Vuillier, G. [Quebec Univ., Rimouski, PQ (Canada). CarFor division d' Audace Technologies; Chaumel, J.L.; Ilinca, A. [Quebec Univ., Rimouski, PQ (Canada). Laboratoire de Recherche en Energie Eolienne

    2009-03-15

    This paper discussed the challenge of solving noise problems associated with wind turbines. Wind power is the leading source of renewable energy in the world. According to the World Council on Energy, the total installed capacity for wind energy was 59,322 MW in 2006, and increased to 150,000 MW by 2010. Noise levels, and the preconceived ideas of noise levels produced by the turbines are among the key challenges facing municipalities. Various phenomena that have an influence on the propagation of noise levels were discussed in this paper, such as geometrical divergence, atmospheric absorption, the effect of soil, topography of the soil, and weather effects. Factors that influence the propagation of acoustic waves include changing weather, atmospheric pressure, and nuisances or obstacles. Road noise, bird noise and noise produced by ice on the blades were considered to be negligible. This paper demonstrated that acoustic levels at any one point can be determined by identifying all levels of noises and their characteristics using specialized tools. 12 refs.

  11. Development and Application of Level 2 Probabilistic Safety Assessment for Nuclear Power Plants. Specific Safety Guide

    International Nuclear Information System (INIS)

    2010-01-01

    The objective of this Safety Guide is to provide recommendations for meeting the IAEA safety requirements in performing or managing a level 2 probabilistic safety assessment (PSA) project for a nuclear power plant; thus it complements the Safety Guide on level 1 PSA. One of the aims of this Safety Guide is to promote a standard framework, standard terms and a standard set of documents for level 2 PSAs to facilitate regulatory and external peer review of their results. It describes all elements of the level 2 PSA that need to be carried out if the starting point is a fully comprehensive level 1 PSA. Contents: 1. Introduction; 2. PSA project management and organization; 3. Identification of design aspects important to severe accidents and acquisition of information; 4. Interface with level 1 PSA: Grouping of sequences; 5. Accident progression and containment analysis; 6. Source terms for severe accidents; 7. Documentation of the analysis: Presentation and interpretation of results; 8. Use and applications of the PSA; Annex I: Example of a typical schedule for a level 2 PSA; Annex II: Computer codes for simulation of severe accidents; Annex III: Sample outline of documentation for a level 2 PSA study.

  12. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya

    2015-01-01

    Several countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading the power infrastructure during peak-power production hours. Regulations have been imposed on the PV systems, where more active power control should be flexibly performed. As an advanced...... control strategy, the Absolute Active Power Control (AAPC) can effectively solve the overloading issues by limiting the maximum possible PV power to a certain level (i.e., the power limitation), and also benefit the inverter reliability. However, its feasibility is challenged by the energy loss....... An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost of Energy (LCOE), the power limit is optimized for the AAPC strategy in this paper. The optimization...

  13. Turbine sound may influence the metamorphosis behaviour of estuarine crab megalopae.

    Directory of Open Access Journals (Sweden)

    Matthew K Pine

    Full Text Available It is now widely accepted that a shift towards renewable energy production is needed in order to avoid further anthropogenically induced climate change. The ocean provides a largely untapped source of renewable energy. As a result, harvesting electrical power from the wind and tides has sparked immense government and commercial interest but with relatively little detailed understanding of the potential environmental impacts. This study investigated how the sound emitted from an underwater tidal turbine and an offshore wind turbine would influence the settlement and metamorphosis of the pelagic larvae of estuarine brachyuran crabs which are ubiquitous in most coastal habitats. In a laboratory experiment the median time to metamorphosis (TTM for the megalopae of the crabs Austrohelice crassa and Hemigrapsus crenulatus was significantly increased by at least 18 h when exposed to either tidal turbine or sea-based wind turbine sound, compared to silent control treatments. Contrastingly, when either species were subjected to natural habitat sound, observed median TTM decreased by approximately 21-31% compared to silent control treatments, 38-47% compared to tidal turbine sound treatments, and 46-60% compared to wind turbine sound treatments. A lack of difference in median TTM in A. crassa between two different source levels of tidal turbine sound suggests the frequency composition of turbine sound is more relevant in explaining such responses rather than sound intensity. These results show that estuarine mudflat sound mediates natural metamorphosis behaviour in two common species of estuarine crabs, and that exposure to continuous turbine sound interferes with this natural process. These results raise concerns about the potential ecological impacts of sound generated by renewable energy generation systems placed in the nearshore environment.

  14. Turbine Sound May Influence the Metamorphosis Behaviour of Estuarine Crab Megalopae

    Science.gov (United States)

    Pine, Matthew K.; Jeffs, Andrew G.; Radford, Craig A.

    2012-01-01

    It is now widely accepted that a shift towards renewable energy production is needed in order to avoid further anthropogenically induced climate change. The ocean provides a largely untapped source of renewable energy. As a result, harvesting electrical power from the wind and tides has sparked immense government and commercial interest but with relatively little detailed understanding of the potential environmental impacts. This study investigated how the sound emitted from an underwater tidal turbine and an offshore wind turbine would influence the settlement and metamorphosis of the pelagic larvae of estuarine brachyuran crabs which are ubiquitous in most coastal habitats. In a laboratory experiment the median time to metamorphosis (TTM) for the megalopae of the crabs Austrohelice crassa and Hemigrapsus crenulatus was significantly increased by at least 18 h when exposed to either tidal turbine or sea-based wind turbine sound, compared to silent control treatments. Contrastingly, when either species were subjected to natural habitat sound, observed median TTM decreased by approximately 21–31% compared to silent control treatments, 38–47% compared to tidal turbine sound treatments, and 46–60% compared to wind turbine sound treatments. A lack of difference in median TTM in A. crassa between two different source levels of tidal turbine sound suggests the frequency composition of turbine sound is more relevant in explaining such responses rather than sound intensity. These results show that estuarine mudflat sound mediates natural metamorphosis behaviour in two common species of estuarine crabs, and that exposure to continuous turbine sound interferes with this natural process. These results raise concerns about the potential ecological impacts of sound generated by renewable energy generation systems placed in the nearshore environment. PMID:23240063

  15. Far-Field Acoustic Power Level and Performance Analyses of F31/A31 Open Rotor Model at Simulated Scaled Takeoff, Nominal Takeoff, and Approach Conditions: Technical Report I

    Science.gov (United States)

    Sree, Dave

    2015-01-01

    Far-field acoustic power level and performance analyses of open rotor model F31/A31 have been performed to determine its noise characteristics at simulated scaled takeoff, nominal takeoff, and approach flight conditions. The nonproprietary parts of the data obtained from experiments in 9- by 15-Foot Low-Speed Wind Tunnel (9?15 LSWT) tests were provided by NASA Glenn Research Center to perform the analyses. The tone and broadband noise components have been separated from raw test data by using a new data analysis tool. Results in terms of sound pressure levels, acoustic power levels, and their variations with rotor speed, angle of attack, thrust, and input shaft power have been presented and discussed. The effect of an upstream pylon on the noise levels of the model has been addressed. Empirical equations relating model's acoustic power level, thrust, and input shaft power have been developed. The far-field acoustic efficiency of the model is also determined for various simulated flight conditions. It is intended that the results presented in this work will serve as a database for comparison and improvement of other open rotor blade designs and also for validating open rotor noise prediction codes.

  16. Vulnerability of US thermoelectric power generation to climate change when incorporating state-level environmental regulations

    Science.gov (United States)

    Liu, Lu; Hejazi, Mohamad; Li, Hongyi; Forman, Barton; Zhang, Xiao

    2017-08-01

    Previous modelling studies suggest that thermoelectric power generation is vulnerable to climate change, whereas studies based on historical data suggest the impact will be less severe. Here we explore the vulnerability of thermoelectric power generation in the United States to climate change by coupling an Earth system model with a thermoelectric power generation model, including state-level representation of environmental regulations on thermal effluents. We find that the impact of climate change is lower than in previous modelling estimates due to an inclusion of a spatially disaggregated representation of environmental regulations and provisional variances that temporarily relieve power plants from permit requirements. More specifically, our results indicate that climate change alone may reduce average generating capacity by 2-3% by the 2060s, while reductions of up to 12% are expected if environmental requirements are enforced without waivers for thermal variation. Our work highlights the significance of accounting for legal constructs and underscores the effects of provisional variances in addition to environmental requirements.

  17. Power infrastructure quality and manufacturing productivity in Africa: A firm level analysis

    International Nuclear Information System (INIS)

    Moyo, Busani

    2013-01-01

    This study sought to examine the impact of the quality of power infrastructure on productivity in African manufacturing firms using data from the World Bank enterprise surveys. We measured power infrastructure quality using the number of hours per day without electricity and the percentage of output lost due to outages and found these indicators to be negative and significant determinants of productivity. These variables seem to be significant determinants in Uganda, Tanzania and Zambia as well as in the food and agriculture sector. To improve economic growth and encourage employment creation, governments in Africa have to come up with measures to improve the reliability of electricity infrastructure. - Highlights: • Power infrastructure quality indicators are found to have a negative and significant effect. • The power quality indicators have varied effects both at country and sector level. • Owning a generator minimises the negative impact of outages in Uganda, Tanzania and Mauritius. • Other controls like labour, capital, foreign ownership etc. have a positive and significant effect. • The firm age variable is insignificant suggesting that accumulated knowledge does not matter

  18. A new high-voltage level-shifting circuit for half-bridge power ICs

    International Nuclear Information System (INIS)

    Kong Moufu; Chen Xingbi

    2013-01-01

    In order to reduce the chip area and improve the reliability of HVICs, a new high-voltage level-shifting circuit with an integrated low-voltage power supply, two PMOS active resistors and a current mirror is proposed. The integrated low-voltage power supply not only provides energy for the level-shifting circuit and the logic circuit, but also provides voltage signals for the gates and sources of the PMOS active resistors to ensure that they are normally-on. The normally-on PMOS transistors do not, therefore, need to be fabricated in the depletion process. The current mirror ensures that the level-shifting circuit has a constant current, which can reduce the process error of the high-voltage devices of the circuit. Moreover, an improved RS trigger is also proposed to improve the reliability of the circuit. The proposed level-shifting circuit is analyzed and confirmed by simulation with MEDICI, and the simulation results show that the function is achieved well. (semiconductor integrated circuits)

  19. Assessment of two-level heat pump installations’ power efficiency for heat supply systems

    Directory of Open Access Journals (Sweden)

    Аlla Е. Denysova

    2015-06-01

    Full Text Available The problem of energy saving becomes one of the most important in power engineering. It is caused by exhaustion of world reserves in hydrocarbon fuel, such as gas, oil and coal representing sources of traditional heat supply. Conventional sources has essential shortcomings: low power, ecological and economic efficiencies, that can be eliminated by using alternative methods of power supply, like the considered one: low-temperature natural heat of ground waters of on the basis of heat pump installations application. The heat supply system considered provides an effective use of two-level heat pump installation operating as heat source the Odessa city ground waters during the lowest ambient temperature period. Proposed is a calculation method of heat pump installations on the basis of geothermal heat supply. Calculated are the values of electric energy consumption N by the compressors’ drive, and the heat supply system transformation coefficient µ for a source of geothermal heat from ground waters of Odessa city allowing to estimate efficiency of two-level heat pump installations.

  20. Islanding the power grid on the transmission level: less connections for more security

    Science.gov (United States)

    Mureddu, Mario; Caldarelli, Guido; Damiano, Alfonso; Scala, Antonio; Meyer-Ortmanns, Hildegard

    2016-10-01

    Islanding is known as a management procedure of the power system that is implemented at the distribution level to preserve sensible loads from outages and to guarantee the continuity in electricity supply, when a high amount of distributed generation occurs. In this paper we study islanding on the level of the transmission grid and shall show that it is a suitable measure to enhance energy security and grid resilience. We consider the German and Italian transmission grids. We remove links either randomly to mimic random failure events, or according to a topological characteristic, their so-called betweenness centrality, to mimic an intentional attack and test whether the resulting fragments are self-sustainable. We test this option via the tool of optimized DC power flow equations. When transmission lines are removed according to their betweenness centrality, the resulting islands have a higher chance of being dynamically self-sustainable than for a random removal. Less connections may even increase the grid’s stability. These facts should be taken into account in the design of future power grids.

  1. A detector for monitoring the onset of cavitation during therapy-level measurements of ultrasonic power

    Energy Technology Data Exchange (ETDEWEB)

    Hodnett, M; Zeqiri, B [National Physical Laboratory, Queens Road, Teddington, Middlesex, TW11 0LW (United Kingdom)

    2004-01-01

    Acoustic cavitation occurring in the water path between a transducer and the target of a radiation force balance can provide a significant source of error during measurements of ultrasonic power. These problems can be particularly acute at physiotherapy levels (>1 W), and low frequencies ({<=} 1 MHz). The cavitating bubbles can absorb and scatter incident ultrasound, leading to an underestimate in the measured power. For these reasons, International Specification standards demand the use of degassed water. This imposes requirements that may actually be difficult to meet, for example, in the case of hospitals. Also, initially degassed water will rapidly re-gas, increasing the likelihood of cavitation occurring. For these reasons, NPL has developed a device that monitors acoustic emissions generated by bubble activity, for detecting the onset of cavitation during power measurements. A commercially available needle hydrophone is used to detect these emissions. The acoustic signals are then monitored using a Cavitation Detector (CD) unit, comprising an analogue electrical filter that may be tuned to detect frequency components generated by cavitating bubbles, and which provides an indication of when the measured level exceeds a pre-defined threshold. This paper describes studies to establish a suitable detection scheme, the principles of operation of the CD unit, and the performance tests carried out with a range of propagation media.

  2. A detector for monitoring the onset of cavitation during therapy-level measurements of ultrasonic power

    International Nuclear Information System (INIS)

    Hodnett, M; Zeqiri, B

    2004-01-01

    Acoustic cavitation occurring in the water path between a transducer and the target of a radiation force balance can provide a significant source of error during measurements of ultrasonic power. These problems can be particularly acute at physiotherapy levels (>1 W), and low frequencies (≤ 1 MHz). The cavitating bubbles can absorb and scatter incident ultrasound, leading to an underestimate in the measured power. For these reasons, International Specification standards demand the use of degassed water. This imposes requirements that may actually be difficult to meet, for example, in the case of hospitals. Also, initially degassed water will rapidly re-gas, increasing the likelihood of cavitation occurring. For these reasons, NPL has developed a device that monitors acoustic emissions generated by bubble activity, for detecting the onset of cavitation during power measurements. A commercially available needle hydrophone is used to detect these emissions. The acoustic signals are then monitored using a Cavitation Detector (CD) unit, comprising an analogue electrical filter that may be tuned to detect frequency components generated by cavitating bubbles, and which provides an indication of when the measured level exceeds a pre-defined threshold. This paper describes studies to establish a suitable detection scheme, the principles of operation of the CD unit, and the performance tests carried out with a range of propagation media

  3. Sound transmission at ground level in a short-grass prairie habitat and its implications for long-range communication in the swift fox Vulpes velox

    DEFF Research Database (Denmark)

    Darden, Safi K; Pedersen, Simon B; Larsen, Ole N

    2008-01-01

    The acoustic environment of swift foxes Vulpes velox vocalizing close to the ground and the effect of propagation on individual identity information in vocalizations were quantified in a transmission experiment in prairie habitat. Sounds were propagated (0.45 m above the ground) at distances up...

  4. A level III PSA for the inherently safe CAREM-25 nuclear power station

    International Nuclear Information System (INIS)

    Baron, Jorge H.; Nunez McLeod, J.; Rivera, S.S.

    2000-01-01

    A Level III PSA has been performed for the inherently safe CAREM-25 nuclear power station, as a requirement for licensing according to argentinian regulations. The CAREM-25 project is still at a detailed design state, therefore only internal events have been considered, and a representative site has been assumed for dose estimations. Several conservative hypothesis have been formulated, but even so an overall core melt frequency of 2.3E -5 per reactor year has been obtained. The risk estimations comply with the regulations. The risk values obtained are compared to the 700MW(e) nuclear power plant Atucha II PSA result, showing an effective risk reduction not only in the severe accident probability but alto in the consequence component of the risk estimation. (author)

  5. Research on the Interior Sound Quality in Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Liao Lian Ying

    2016-01-01

    Full Text Available Even the overall level of vehicle interior noise of hybrid electric vehicle (HEV reduced to a certain degree, the vibration and noise generated by the engine, motor, generator and power split have made greater effect on the vehicle interior sound quality in HEV. In order to research the feature of vehicle interior sound quality in HEV, the HEV is used to be the research object, the binaural noise sample of the driver when playing different kinds of music in the vehicle with the speed of sixty kilometers per hour is collected. ArtemiS is used to conduct frequency division processing, so as to obtain the relative weight of each frequency band and the overall noise. The tone, roughness and sharpness of sound quality subjective evaluation parameters are quantified, the SPSS is used to establish the linear regression model of the sample, and the best masking music tracks are found out. Then, the sound samples that contains the best music tracks and the simple vehicle interior noise are re-collected, the regression model and ArtemiS are used to predict the subjective evaluation value. The research results show that when adding the music, the tone degree rises and the lowering degree decreases, thus the disturbing degree reduces, which significantly improves the sound quality in the HEV.

  6. Advanced I and C system of security level for nuclear power station

    International Nuclear Information System (INIS)

    Liu Yanyang

    2001-01-01

    Advanced I and C system of security level using for PWR developed by Framatome and Schneider collective, SPINLINE3, are introduced. The technology is used to outside reactor nuclear measurement system in Qinshan II period. It's succeed benefits by Framatome and Schneider's more years development experience in nuclear power station digitallization security level I and C system field, which improve security and reliability of PWR, and, easy operation and maintains. SPINLINE3 based on digitallization and modularization technical proposal, and covered entireness reactor protect system and correlative control system. The paper also introduce CLARISSE (computer aided design aid) and SCADE (embedded software aid) for developing SPINLINE3. SPINLINE3 fills correlative IS and rule, based on software and hardware unit which certificate and launch into operation. After brief review of Framatome and Schneider's experience, the paper are introducing design guideline, application technology and how to fill demand of security level I and C system

  7. Biographical learning in top-level coaching - personal styles and the power of practical sense

    DEFF Research Database (Denmark)

    Christensen, Mette Krogh

    aspects of coaching expertise: 1) the coaches’ descriptions of their development of expertise as a “personal journey” and a matter of unique pathways, and 2) the coaches’ use of social constructed practical sense in their daily work, particularly in identification and assessment of skillfulness and talent......Abstract for “Sports and Coaching – Past and Futures” MMU Institute for Performance Research, 25/26 June 2011 Author: Christensen, Mette Krogh Associate Professor, Ph.D. Institute of Sports Science and Clinical Biomechanics University of Southern Denmark Campusvej 55, 5230 Odense M, Denmark Title......: Biographical learning in top-level coaching - personal styles and the power of practical sense. There is a growing body of studies in sports coaching cultures, comprising research focusing on the individual learning processes and life histories of top-level coaches. Even if top-level sport has become...

  8. Urban Sound Ecologies

    DEFF Research Database (Denmark)

    Groth, Sanne Krogh; Samson, Kristine

    2013-01-01

    Within recent years, there has been a renewed focus on sound in urban environments. From sound installations in public space to sound festivals in alternative settings, we find a common interest in sound art relating to the urban environment. Artworks or interventions presented in such contexts s...

  9. Sound reproduction system

    NARCIS (Netherlands)

    Boone, M.M.; De Vries, D.; Horbach, U.

    2002-01-01

    Arrangement of a sound reproduction system (1), including at least one input (2), a sound field generator (4), a loudspeaker panel (10); the at least one input (2) connected to the sound filed generator (4), and the sound filed (4) connected to the loudspeaker panel (10); the at least one input (2)

  10. The Sound of Science

    Science.gov (United States)

    Merwade, Venkatesh; Eichinger, David; Harriger, Bradley; Doherty, Erin; Habben, Ryan

    2014-01-01

    While the science of sound can be taught by explaining the concept of sound waves and vibrations, the authors of this article focused their efforts on creating a more engaging way to teach the science of sound--through engineering design. In this article they share the experience of teaching sound to third graders through an engineering challenge…

  11. Electronic timer for sounding rocket payload use

    Science.gov (United States)

    Williams, C. P.

    1986-01-01

    An electronic timer has been developed for sounding rocket use. The timer uses CMOS technology for low power consumption and has a battery back-up to keep the timing circuit active in case of a dropout on the payload power bus. Time-event decoding is done by programming EPROM's which enable a +28 volt dc sourcing output. There are 32 discrete outputs which can provide +28 volt dc into a minimum load impedance of 150 ohms. Inputs are designed to operate on standard CMOS voltage levels, but they can withstand +28 volts dc without damage. The timer can be started by either 'G' or lift-off switch closure or umbilical release at lift-off.

  12. Influence of nuclear fuel cycle duration and reprocessing losses level on the nuclear power system structure

    International Nuclear Information System (INIS)

    Alekseev, P. N.; Dudnikov, A. A.; Subbotin, S. A.

    2004-01-01

    It is shown that three-component Nuclear Power (NP) system consisting of thermal reactors (TR), fast reactors (FR) and molten salt reactors-burners (MSR) can operate in mode when actinides in system are not stored up proportionally to energy generated but are practically at steady level proportionally to system power. In the paper there was considered the influence of nuclear fuel cycle (NFC) duration and level of irretrievable reprocessing losses on NP structure and fuel consumption efficiency. U-Pu and U-Th variants of NP systems were considered with various levels of irretrievable reprocessing losses for all actinides - 0%, 0.1% and 1%, and various duration of cooling and reprocessing time of TR fuel cycle (TRR time) - 3 years, 6 years, 9 years, 20 years. Steady state calculations were performed for three-component NP systems and there were obtained steady state amounts and radioactivity of actinides for main components of NFC closed by actinides. Also, there were obtained rates and radioactivity of accumulation of actinide irretrievable reprocessing losses. (authors)

  13. Modeling Photovoltaic Module-Level Power Electronics in the System Advisor Model; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-07-01

    Module-level power electronics, such as DC power optimizers, microinverters, and those found in AC modules, are increasing in popularity in smaller-scale photovoltaic (PV) systems as their prices continue to decline. Therefore, it is important to provide PV modelers with guidelines about how to model these distributed power electronics appropriately in PV modeling software. This paper extends the work completed at NREL that provided recommendations to model the performance of distributed power electronics in NREL’s popular PVWatts calculator [1], to provide similar guidelines for modeling these technologies in NREL's more complex System Advisor Model (SAM). Module-level power electronics - such as DC power optimizers, microinverters, and those found in AC modules-- are increasing in popularity in smaller-scale photovoltaic (PV) systems as their prices continue to decline. Therefore, it is important to provide PV modelers with guidelines about how to model these distributed power electronics appropriately in PV modeling software.

  14. A two-level structure for advanced space power system automation

    Science.gov (United States)

    Loparo, Kenneth A.; Chankong, Vira

    1990-01-01

    The tasks to be carried out during the three-year project period are: (1) performing extensive simulation using existing mathematical models to build a specific knowledge base of the operating characteristics of space power systems; (2) carrying out the necessary basic research on hierarchical control structures, real-time quantitative algorithms, and decision-theoretic procedures; (3) developing a two-level automation scheme for fault detection and diagnosis, maintenance and restoration scheduling, and load management; and (4) testing and demonstration. The outlines of the proposed system structure that served as a master plan for this project, work accomplished, concluding remarks, and ideas for future work are also addressed.

  15. Evaluating the level and nature of sustainable development for a geothermal power plant

    International Nuclear Information System (INIS)

    Phillips, Jason

    2010-01-01

    The paper provides for an evaluation of the potential level and nature of sustainable development of the Sabalan geothermal power plant in NW Iran, to be operational in 2011. The paper achieves this by applying a mathematical model of sustainable development developed by the author (re: Phillips), in respect to the Environmental Impact Assessment (EIA) conducted by Yousefi et al. using the Rapid Impact Assessment Matrix (RIAM) methodology (re: Pastakia; Pastakia and Jensen). Using a model application methodology developed for the RIAM, the results indicated that the nature of sustainable development for Sabalan was considered to be very weak (S = 0.063). This was due to the imbalance between negative environmental impacts and positive socio-economic impacts deriving from the project. Further, when placed into context with a similar set of results obtained from the EIA of the Tuzla geothermal power plant by Baba also using the RIAM methodology, then the similarities between the results obtained raises some legimate questions as to the sustainable development credentials of geothermal power production. (author)

  16. What day-ahead reserves are needed in electric grids with high levels of wind power?

    International Nuclear Information System (INIS)

    Mauch, Brandon; Apt, Jay; Jaramillo, Paulina; Carvalho, Pedro M S

    2013-01-01

    Day-ahead load and wind power forecasts provide useful information for operational decision making, but they are imperfect and forecast errors must be offset with operational reserves and balancing of (real time) energy. Procurement of these reserves is of great operational and financial importance in integrating large-scale wind power. We present a probabilistic method to determine net load forecast uncertainty for day-ahead wind and load forecasts. Our analysis uses data from two different electric grids in the US with similar levels of installed wind capacity but with large differences in wind and load forecast accuracy, due to geographic characteristics. We demonstrate that the day-ahead capacity requirements can be computed based on forecasts of wind and load. For 95% day-ahead reliability, this required capacity ranges from 2100 to 5700 MW for ERCOT, and 1900 to 4500 MW for MISO (with 10 GW of installed wind capacity), depending on the wind and load forecast values. We also show that for each MW of additional wind power capacity for ERCOT, 0.16–0.30 MW of dispatchable capacity will be used to compensate for wind uncertainty based on day-ahead forecasts. For MISO (with its more accurate forecasts), the requirement is 0.07–0.13 MW of dispatchable capacity for each MW of additional wind capacity. (letter)

  17. Allowable Residual Contamination Levels in soil for decommissioning the Shippingport Atomic Power Station site

    International Nuclear Information System (INIS)

    Kennedy, W.E. Jr.; Napier, B.A.; Soldat, J.K.

    1983-09-01

    As part of decommissioning the Shippingport Atomic Power Station, a fundamental concern is the determination of Allowable Residual Contamination Levels (ARCL) for radionuclides in the soil at the site. The ARCL method described in this report is based on a scenario/exposure-pathway analysis and compliance with an annual dose limit for unrestricted use of the land after decommissioning. In addition to naturally occurring radionuclides and fallout from weapons testing, soil contamination could potentially come from five other sources. These include operation of the Shippingport Station as a pressurized water reactor, operations of the Shippingport Station as a light-water breeder, operation of the nearby Beaver Valley reactors, releases during decommissioning, and operation of other nearby industries, including the Bruce-Mansfield coal-fired power plants. ARCL values are presented for 29 individual radionculides and a worksheet is provided so that ARCL values can be determined for any mixture of the individual radionuclides for any annual dose limit selected. In addition, a worksheet is provided for calculating present time soil concentration value that will decay to the ARCL values after any selected period of time, such as would occur during a period of restricted access. The ARCL results are presented for both unconfined (surface) and confined (subsurface) soil contamination. The ARCL method and results described in this report provide a flexible means of determining unrestricted-use site release conditions after decommissioning the Shippingport Atomic Power Station

  18. An objective measure for the sensitivity of room impulse response and its link to a diffuse sound field.

    Science.gov (United States)

    Prislan, Rok; Brunskog, Jonas; Jacobsen, Finn; Jeong, Cheol-Ho

    2014-10-01

    This study is relevant to acoustic measurements in reverberation rooms such as measurements of sound transmission, sound absorption, and sound power levels of noise sources. The study presents a quantitative measure for the diffuseness in a room, which is first introduced theoretically and subsequently examined experimentally. The sensitivity of a room due to changes in the initial conditions is quantified by measuring a pair of impulse responses in a room differing only in the sound source position. Such changes are linked to mixing and the diffuse sound field. The measure is based on the maximum of the absolute value of the cross-correlation between the time windowed sections of the two impulse responses. By integrating this quantity normalized by the energy of the impulse response of the room, a single number rating is obtained. Results based on three sets of experiments indicate that the diffusers and absorbers in the room influence the proposed sensitivity measures systematically.

  19. Grid Connection of Wave Power Farm Using an N-Level Cascaded H-Bridge Multilevel Inverter

    Directory of Open Access Journals (Sweden)

    Rickard Ekström

    2013-01-01

    Full Text Available An N-level cascaded H-bridge multilevel inverter is proposed for grid connection of large wave power farms. The point-absorber wave energy converters are individually rectified and used as isolated DC-sources. The variable power characteristics of the wave energy converters are discussed, and a method of mitigating this issue is demonstrated. The complete power control system is given in detail and has been experimentally verified for a single-phase setup of the 9-level inverter. Theoretical expressions of the power sharing between multilevel cells are derived and show good correspondence with the experimental results.

  20. Effect of heliostat size on the levelized cost of electricity for power towers

    Science.gov (United States)

    Pidaparthi, Arvind; Hoffmann, Jaap

    2017-06-01

    The objective of this study is to investigate the effects of heliostat size on the levelized cost of electricity (LCOE) for power tower plants. These effects are analyzed in a power tower with a net capacity of 100 MWe, 8 hours of thermal energy storage and a solar multiple of 1.8 in Upington, South Africa. A large, medium and a small size heliostat with a total area of 115.56 m2, 43.3 m2 and 15.67 m2 respectively are considered for comparison. A radial-staggered pattern and an external cylindrical receiver are considered for the heliostat field layouts. The optical performance of the optimized heliostat field layouts has been evaluated by the Hermite (analytical) method using SolarPILOT, a tool used for the generation and optimization of the heliostat field layout. The heliostat cost per unit is calculated separately for the three different heliostat sizes and the effects due to size scaling, learning curve benefits and the price index is included. The annual operation and maintenance (O&M) costs are estimated separately for the three heliostat fields, where the number of personnel required in the field is determined by the number of heliostats in the field. The LCOE values are used as a figure of merit to compare the different heliostat sizes. The results, which include the economic and the optical performance along with the annual O&M costs, indicate that lowest LCOE values are achieved by the medium size heliostat with an area of 43.3 m2 for this configuration. This study will help power tower developers determine the optimal heliostat size for power tower plants currently in the development stage.

  1. Radioactivity level of the ambient environment of Anren bone-coal power station

    International Nuclear Information System (INIS)

    Ye Jida; Liu Hongshi; Wu Zongmei; Wu Xiaofei

    2002-01-01

    The radioactivity level of the ambient environment of Anren Bone-coal Power Station (BCPS) was investigated systematically. The γ radiation dose rate level in the environment, the content of 238 U and 226 Ra in the ambient soil and the farmland in the direction of downwind, the concentrations of 238 U, 232 Th, 226 Ra, 40 K and 222 Rn, as well as α potential energy in air, and the concentrations of natural U and Th in effluent are all higher than the corresponding values of the reference site. The additional annual effective dose equivalent to the residents living in the houses made of bone-coal cinder brick is 2.7 mSv

  2. Radiochemical methodologies applied to analytical characterization of low and intermediate level wastes from nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Roberto Pellacani G.; Júnior, Aluísio Souza R.; Kastner, Geraldo F.; Temba, Eliane S.C.; Oliveira, Thiago C. de; Amaral, Ângela M.; Franco, Milton B., E-mail: rpgm@cdtn.br, E-mail: reisas@cdtn.br, E-mail: gfk@cdtn.br, E-mail: esct@cdtn.br, E-mail: tco@cdtn.br, E-mail: ama@cdtn.br, E-mail: francom@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants. In this program some radionuclides, {sup 3}H, {sup 14}C, {sup 55}Fe, {sup 59}Ni, {sup 63}Ni, {sup 90}Sr, {sup 93}Zr, {sup 94}Nb, {sup 99}Tc, {sup 129}I, {sup 235}U, {sup 238}U, {sup 238}Pu, {sup 239}+{sup 240}Pu, {sup 241}Pu, {sup 242}Pu, {sup 241}Am, {sup 242}Cm e {sup 243}+{sup 244}Cm, were determined in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was established. (author)

  3. Potential for de-regulated disposal of very low level wastes from nuclear power plants

    International Nuclear Information System (INIS)

    Davis, J.P.; Chan, D.W.

    1987-01-01

    The purpose of the study discussed in this paper was to review the characteristics of low level waste streams generated in commercial nuclear power facilities to determine which may be suitable for disposal by methods other than transfer to a facility licensed by the Nuclear Regulatory Commission (NRC) and to evaluate the benefits, risks, and costs of exempting such very low level wastes (VLW) from the disposal requirements of 10 CFR Part 61. Of course, wastes that no longer require regulation of their radiological properties are still subject to the regulatory controls - federal, state, or local - that affect non-radioactive wastes of similar chemical and physical properties and similar origins. This study addressed radiological aspects only, and assumed, in its evaluations, that the wastes can and will be disposed of in accordance with all other applicable requirements. 4 references, 1 figure, 6 tables

  4. Statistics of natural binaural sounds.

    Directory of Open Access Journals (Sweden)

    Wiktor Młynarski

    Full Text Available Binaural sound localization is usually considered a discrimination task, where interaural phase (IPD and level (ILD disparities at narrowly tuned frequency channels are utilized to identify a position of a sound source. In natural conditions however, binaural circuits are exposed to a stimulation by sound waves originating from multiple, often moving and overlapping sources. Therefore statistics of binaural cues depend on acoustic properties and the spatial configuration of the environment. Distribution of cues encountered naturally and their dependence on physical properties of an auditory scene have not been studied before. In the present work we analyzed statistics of naturally encountered binaural sounds. We performed binaural recordings of three auditory scenes with varying spatial configuration and analyzed empirical cue distributions from each scene. We have found that certain properties such as the spread of IPD distributions as well as an overall shape of ILD distributions do not vary strongly between different auditory scenes. Moreover, we found that ILD distributions vary much weaker across frequency channels and IPDs often attain much higher values, than can be predicted from head filtering properties. In order to understand the complexity of the binaural hearing task in the natural environment, sound waveforms were analyzed by performing Independent Component Analysis (ICA. Properties of learned basis functions indicate that in natural conditions soundwaves in each ear are predominantly generated by independent sources. This implies that the real-world sound localization must rely on mechanisms more complex than a mere cue extraction.

  5. Trending of low level events and near misses to enhance safety performance in nuclear power plants

    International Nuclear Information System (INIS)

    2005-11-01

    The IAEA Safety Fundamentals publication, Safety of Nuclear Installations, Safety Series No. 110, states the need for operating organizations to establish a programme for the collection and analysis of operating experience in nuclear power plants. Such a programme ensures that operating experience is analysed, events important to safety are reviewed in depth, and lessons learned are disseminated to the staff of the organization and to relevant national and international organizations. As a result of the effort to enhance safety in operating organizations, incidents are progressively decreasing in number and significance. This means that in accordance with international reporting requirements the amount of collected data becomes less sufficient to draw meaningful statistical conclusions. This is where the collection and trend analysis of low level events and near misses can prove to be very useful. These trends can show which of the safety barriers are weak or failing more frequently. Evaluation and trending of low level events and near misses will help to prevent major incidents because latent weaknesses have been identified and corrective actions taken to prevent recurrence. This leads to improved safety and production. Low level events and near misses, which may reach several thousand per reactor operating year, need to be treated by the organizations as learning opportunities. A system for capturing these low level events and near misses truly needs to be an organization-wide system in which all levels of the organization, including contractors, participate. It is desirable that the overall operational experience feedback (OEF) process should integrate the lessons learned and the associated data from significant events with those of lower level events and near misses. To be able to effectively implement a process dealing with low level events and near misses, it is necessary that the organization have a well established OEF process for significant events

  6. Longitudinal Tracking of Sound Exposure and Hearing Aid Usage through Objective Data Logs.

    Science.gov (United States)

    Doyle, John B; Raghunathan, Rohit R; Cellum, Ilana; Li, Gen; Golub, Justin S

    2018-03-01

    Objective To use data-logging technology to objectively track and identify predictors of hearing aid (HA) usage and aided sound exposure. Study Design Case series with planned data collection. Setting Tertiary academic medical center. Subjects and Methods Individuals with HAs between 2007 and 2016 were included (N = 431; mean, 74.6 years; 95% CI, 73.1-76.0). Data-logging technology intrinsic to new-generation HAs was enabled to track usage and sound exposure. With multivariable linear regression, age, sex, number of audiology visits, duration of audiologic follow-up, pure tone average, and HA side were assessed as predictors of usage (hours/day) and aided sound exposure (dB-hours/day; ie, "dose" of sound per day). Results Mean follow-up was 319 days (95% CI, 277-360). Mean HA usage was 8.4 hours/day (95% CI, 8.0-8.8; N = 431). Mean aided sound exposure was 440 dB-hours/day (95% CI, 385-493; n = 110). HA use (β < 0.001, P = .45) and aided sound exposure (β = -0.006, P = .87) were both stable over time. HA usage was associated only with hearing loss level (pure tone average; β = 0.030, P = .04). Aided sound exposure was associated only with duration of audiologic follow-up (β = 0.100, P = .02). Conclusion While measurement of HA use has traditionally relied on subjective reporting, data logging offers an objective tool to longitudinally track HA use and sound exposure. We demonstrate the feasibility of using this potentially powerful research tool. Usage and sound exposure were stable among patients throughout the study period. Use was greater among subjects with greater hearing loss. Maximizing aided sound exposure might be possible through continued audiology follow-up visits.

  7. Load leveling efforts of The Hokkaido Electric Power Co. Inc.; Hokkaido Denryoku no fuka heijunka eno torikumi ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    The Hokkaido Electric Power Co., Inc., aiming to enhance power generation efficiency through power load levelling, strives to expand and substantiate its electricity billing menu and to popularize and encourage the use of levelling-oriented apparatuses and systems most of which are designed for utilizing midnight power. The billing menu has in it a snow-melting power which is cut off for load levelling during the peak demand time zone. For domestic use, a time zone-specified lighting system named Dream Eight is created, which is one of the billing systems dependent upon time zone. Introduced therein for industrial use is a demand/supply adjustment contract system. Furthermore, in compliance with the amended Electricity Business Law that came into force in 1995, efforts are under way for revising the period wherein power is to be supplied for melting snow, expanding the scope of application of the power supply system dependent upon time zone, and newly introducing a heat accumulation assisted peak adjustment contract system and an operation adjustment contract system. As for business efforts in relation to load levelling, the company proposes household electrical systems centering about 200V high-efficiency apparatuses, electric water warmer contributing to the enhancement of year-round load levelling, popularization and reinforcement of electric snow melting systems, and power utilizing technologies capable of meeting local demands raised for example by agriculture and fishery.

  8. Evaluation of environmental tritium level in the area of Cernavoda Nuclear Power Plant

    International Nuclear Information System (INIS)

    Paunescu, N.; Cotarlea, M.; Galeriu, D.; Margineanu, R.; Mocanu, N.

    1997-01-01

    This work is a continuation of the study entitled E valuation of environmental tritium levels before and after start of a new tritium source for model verification' that commenced two years ago as part of an European research contract having as objective the 'Investigations and Modelling of the Dynamics of Environmental HT/HTO/OBT Levels Resulting from the Tritium Releases'. The aim of this study was to evaluate the environmental tritium level in pre-operational stage of Cernavoda Nuclear Power Plant and the dynamics of variation of tritium concentration in the first operational years of NPP, for determination of site-specific transfer parameters and model validation. Representative samples for Cernavoda area were analyzed; - air humidity; - water from Danube River, Danube-Black Sea Canal and lakes; - drinking, rain and snow water; - HTO concentration in soils at different depths; - tissue free water tritium in vegetal and animal foodstuffs relevant for human diets like cereals (wheat, maize, barley). vegetables (potatoes, tomato, cabbage, onion, bean), grapes and wine. The mean concentration of tritium obtained in 1996 for these types of measurements is presented. The values of tritium concentration in air, water, soil and plants are as low as for areas without contaminating sources. The operation in 1996 of the Cernavoda NPP did not modify the tritium environmental level. (authors)

  9. Mechanical Demands of the Hang Power Clean and Jump Shrug: A Joint-Level Perspective.

    Science.gov (United States)

    Kipp, Kristof; Malloy, Philip J; Smith, Jordan C; Giordanelli, Matthew D; Kiely, Michael T; Geiser, Christopher F; Suchomel, Timothy J

    2018-02-01

    Kipp, K, Malloy, PJ, Smith, J, Giordanelli, MD, Kiely, MT, Geiser, CF, and Suchomel, TJ. Mechanical demands of the hang power clean and jump shrug: a joint-level perspective. J Strength Cond Res 32(2): 466-474, 2018-The purpose of this study was to investigate the joint- and load-dependent changes in the mechanical demands of the lower extremity joints during the hang power clean (HPC) and the jump shrug (JS). Fifteen male lacrosse players were recruited from a National Collegiate Athletic Association DI team, and completed 3 sets of the HPC and JS at 30, 50, and 70% of their HPC 1 repetition maximum (1RM HPC) in a counterbalanced and randomized order. Motion analysis and force plate technology were used to calculate the positive work, propulsive phase duration, and peak concentric power at the hip, knee, and ankle joints. Separate 3-way analysis of variances were used to determine the interaction and main effects of joint, load, and lift type on the 3 dependent variables. The results indicated that the mechanics during the HPC and JS exhibit joint-, load-, and lift-dependent behavior. When averaged across joints, the positive work during both lifts increased progressively with external load, but was greater during the JS at 30 and 50% of 1RM HPC than during the HPC. The JS was also characterized by greater hip and knee work when averaged across loads. The joint-averaged propulsive phase duration was lower at 30% than at 50 and 70% of 1RM HPC for both lifts. Furthermore, the load-averaged propulsive phase duration was greater for the hip than the knee and ankle joint. The joint-averaged peak concentric power was the greatest at 70% of 1RM for the HPC and at 30%-50% of 1RM for the JS. In addition, the joint-averaged peak concentric power of the JS was greater than that of the HPC. Furthermore, the load-averaged peak knee and ankle concentric joint powers were greater during the execution of the JS than the HPC. However, the load-averaged power of all joints differed

  10. Power

    DEFF Research Database (Denmark)

    Elmholdt, Claus Westergård; Fogsgaard, Morten

    2016-01-01

    In this chapter, we will explore the dynamics of power in processes of creativity, and show its paradoxical nature as both a bridge and a barrier to creativity in organisations. Recent social psychological experimental research (Slighte, de Dreu & Nijstad, 2011) on the relation between power...... and floating source for empowering people in the organisation. We will explore and discuss here the potentials, challenges and pitfalls of power in relation to creativity in the life of organisations today. The aim is to demonstrate that power struggles may be utilised as constructive sources of creativity...

  11. Design of a two-level power system linear state estimator

    Science.gov (United States)

    Yang, Tao

    The availability of synchro-phasor data has raised the possibility of a linear state estimator if the inputs are only complex currents and voltages and if there are enough such measurements to meet observability and redundancy requirements. Moreover, the new digital substations can perform some of the computation at the substation itself resulting in a more accurate two-level state estimator. The objective of this research is to develop a two-level linear state estimator processing synchro-phasor data and estimating the states at both the substation level and the control center level. Both the mathematical algorithms that are different from those in the present state estimation procedure and the layered architecture of databases, communications and application programs that are required to support this two-level linear state estimator are described in this dissertation. Besides, as the availability of phasor measurements at substations will increase gradually, this research also describes how the state estimator can be enhanced to handle both the traditional state estimator and the proposed linear state estimator simultaneously. This provides a way to immediately utilize the benefits in those parts of the system where such phasor measurements become available and provides a pathway to transition to the smart grid of the future. The design procedure of the two-level state estimator is applied to two study systems. The first study system is the IEEE-14 bus system. The second one is the 179 bus Western Electricity Coordinating Council (WECC) system. The static database for the substations is constructed from the power flow data of these systems and the real-time measurement database is produced by a power system dynamic simulating tool (TSAT). Time-skew problems that may be caused by communication delays are also considered and simulated. We used the Network Simulator (NS) tool to simulate a simple communication system and analyse its time delay performance. These

  12. Sound : Viimased uusaastakingid

    Index Scriptorium Estoniae

    1998-01-01

    Plaatidest, mida soovitatakse kingikotti: En Vogue."Hold On", Madonna "The Power Of Goodbye /Little Star", Busta Rhymes "Extincion Level Event. The Final World Front", Vanessa Williams "The First Ten Years.Greatest Hits" ja Era "S/T"

  13. Synthesized size-sound sound symbolism

    NARCIS (Netherlands)

    Lockwood, G.F.; Hagoort, P.; Dingemanse, M.; Papafragou, A.; Grodner, D.; Mirman, D.; Trueswell, J.

    2016-01-01

    Studies of sound symbolism have shown that people can associate sound and meaning in consistent ways when presented with maximally contrastive stimulus pairs of nonwords such as bouba/kiki (rounded/sharp) or mil/mal (small/big). Recent work has shown the effect extends to antonymic words from

  14. Fourier power spectrum characteristics of face photographs: attractiveness perception depends on low-level image properties.

    Science.gov (United States)

    Menzel, Claudia; Hayn-Leichsenring, Gregor U; Langner, Oliver; Wiese, Holger; Redies, Christoph

    2015-01-01

    We investigated whether low-level processed image properties that are shared by natural scenes and artworks - but not veridical face photographs - affect the perception of facial attractiveness and age. Specifically, we considered the slope of the radially averaged Fourier power spectrum in a log-log plot. This slope is a measure of the distribution of special frequency power in an image. Images of natural scenes and artworks possess - compared to face images - a relatively shallow slope (i.e., increased high spatial frequency power). Since aesthetic perception might be based on the efficient processing of images with natural scene statistics, we assumed that the perception of facial attractiveness might also be affected by these properties. We calculated Fourier slope and other beauty-associated measurements in face images and correlated them with ratings of attractiveness and age of the depicted persons (Study 1). We found that Fourier slope - in contrast to the other tested image properties - did not predict attractiveness ratings when we controlled for age. In Study 2A, we overlaid face images with random-phase patterns with different statistics. Patterns with a slope similar to those in natural scenes and artworks resulted in lower attractiveness and higher age ratings. In Studies 2B and 2C, we directly manipulated the Fourier slope of face images and found that images with shallower slopes were rated as more attractive. Additionally, attractiveness of unaltered faces was affected by the Fourier slope of a random-phase background (Study 3). Faces in front of backgrounds with statistics similar to natural scenes and faces were rated as more attractive. We conclude that facial attractiveness ratings are affected by specific image properties. An explanation might be the efficient coding hypothesis.

  15. Four Key Keys to Powerful Presentations in PowerPoint: Take Your Presentations to the Next Level

    Science.gov (United States)

    Howell, Dusti D.

    2008-01-01

    If a person is on a presentation and he/she does not know how to go back to a previous PowerPoint slide, his/her credibility will be clouded and the audience will become frustrated. More sophisticated presenters use handheld remotes to control the basic navigation of slides. Even in this case, keyboard shortcuts can be an added benefit. For those…

  16. Improved method for positioning mobile phones based on series of measured reception power levels

    Science.gov (United States)

    Kuipers, Martin; Majewski, Kurt; Schmitz, Heiko; Stadelmeyer, Peter

    2003-08-01

    Finding the position of a mobile user has become important for many wireless applications. There are many methods, which fulfill this task but require extensions of the network or the terminals. The technique presented here is based on the received signal powers obtained from standard measurements. It uses a restricted search area and a time series of measurements. The search area is determined by the intersection of the maximum area covered by the serving cell and a ring determined from round-trip time measurements. A Viterbi-like algorithm is used to compare the time series of reception power levels measured by the handset with predicted values from the network planning process. It returns a weighted average of possible positions. Since only standard measurements are used, no changes of the network or the handsets are required, making the method inexpensive. Furthermore, the method can be used for traffic localization. The method has actually been implemented by Siemens for GSM. Extensive field trials in an operating network in Germany showed an accuracy of 130 meters in urban environments and about 300 meters in suburban and rural areas. Since similar measurements exist in UMTS networks, the method is applicable in UTRAN as well.

  17. Development of Soil Derived Concentration Guidance Levels for Decommissioning at Overseas Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Wook; Yoon, Suk Bon; Kim, Jeongju [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    In Korea, the criteria are expected to be given in terms of dose as in US and Spain. However, since dose cannot be measured, corresponding measurable concentration limits, so-called Derived Concentration Guidance Levels (DCGLs), should be developed for each radionuclide which is expected to be present in the site. Also, as they serve as a goal of decommissioning and direct dismantling and decontamination methods applicable to the site, DCGLs should be developed in the early phase of decommissioning. This paper describes how each overseas nuclear power plant developed its site-specific Soil DCGLs: what kind of post closure use of the site (scenario) was assumed and how the site-specific Soil DCGLs were calculated based on the scenario assumed for each plant. Through this, it is intended to derive lessons learned which will be instructive for future decommissioning of domestic nuclear power plants including Kori Unit 1. It is very important to have as good under-standing as possible of characteristics of the site by collection of relevant information and data in order to apply a scenario which is most foreseeable and plausible for a site to be decommissioned and to provide site-specific inputs to the calculation of the Soil DCGLs. These efforts will help to have not-overly conservative values for the Soil DCGLs, thus thereby reducing the costs and time needed for performing the decommissioning.

  18. Determination of 93Zr in medium and low level radioactive wastes from Brazilian nuclear power plants

    International Nuclear Information System (INIS)

    Oliveira, Thiago C.; Oliveira, Arno H.

    2015-01-01

    The majority of long-lived radionuclides produced in the nuclear power plants can be regarded as difficult-to-measure radionuclides (RDM), hence chemical separation is necessary before the nuclear measurement of them. The zirconium isotope 93 Zr is a long-lived pure β-particle-emitting radionuclide produced from 235 U fission and from neutron activation of the stable isotope 92 Zr and thus occurring as one of the radionuclides found in nuclear reactors. Due to its long half-life, 93 Zr is one of the radionuclides of interest for the performance of assessment studies of waste storage or disposal. Two different methodologies based on extractive resins and LSC and ICP-MS techniques that enables the 93 Zr determination in medium (ILW) and low level (LLW) radioactive wastes samples from Brazilian nuclear power plants has been developed in our laboratory. Analyzing real samples 65% and 75% chemical yields for 93 Zr recovery were achieved for ICP-MS and LSC techniques, respectively. The detection limits were 0.045 μg.L -1 for ICP-MS and 0.05 Bq.L -1 for LSC techniques. (author)

  19. Levelized Cost of Energy Analysis of a Wind Power Generation System at Búrfell in Iceland

    Directory of Open Access Journals (Sweden)

    Birgir Freyr Ragnarsson

    2015-09-01

    Full Text Available Wind energy harnessing is a new energy production alternative in Iceland. Current installed wind power in Iceland sums to 1.8 MW, which in contrast is 0.1% of the country’s total electricity production. This article is dedicated to the exploration of the potential cost of wind energy production at Búrfell in the south of Iceland. A levelized cost of energy (LCOE approach was applied to the estimation of the potential cost. Weibull simulation is used to simulate wind data for calculations. A confirmation of the power law is done by comparing real data to calculated values. A modified Weibull simulation is verified by comparing results with actual on-site test wind turbines. A wind farm of 99MWis suggested for the site. Key results were the capacity factor (CF at Búrfell being 38.15% on average and that the LCOE for wind energy was estimated as 0.087–0.088 USD/kWh (assuming 10% weighted average cost of capital (WACC, which classifies Búrfell among the lowest LCOE sites for wind energy in Europe.

  20. Management of Low Level Rad-Waste Arising From Nuclear Power Stations in Japan

    International Nuclear Information System (INIS)

    Kaneda, Hisashi

    1987-01-01

    In nuclear power stations in Japan, in order to reduce radioactivity release into the environment based on the concept of ALARA, various improvements of the gaseous and liquid waste treatment systems have been made in both aspects of facilities and operations as follows: In order to reduce the release of gaseous waste, the following facilities were introduced: Charcoal bed typed noble gas holdup facility, Clean steam supply system for turbine gland seal, No leak typed valve In order to reduce the release of liquid waste, the following measures were taken: Evaporating floor drain, Evaporating laundry drain;, Demoralizing plant surplus water by a mix bed typed ion exchange resin. As a result of these counter measures, the release of gaseous and liquid radioactivity into the environment has been reduced gradually, and is now virtually 'zero' as shown in Islet. 1. Contrary to reduction in radioactivity release into the environment, residual radioactivity inside nuclear power station has made consequent increase of low level radioactive wastes in the form of solid

  1. Adaptative control with non-minimum phase system. Application to level control in PWR power plant steam generator

    International Nuclear Information System (INIS)

    Bihoreau, C.

    1981-03-01

    This thesis presents the proposal for a water control level method likely to improve performance, especially at low power. Particular problems are analyzed in detail. Finally, computerized simulations are presented; they confirm the algorithm performance [fr

  2. Evaluation of environmental tritium level in preoperational period of Cernavoda CANDU Nuclear Power Plant

    International Nuclear Information System (INIS)

    Paunescu, N.; Cotarlea, M.; Galeriu, D.; Margineanu, R.; Mocanu, N.

    1999-01-01

    In Romania, a CANDU Nuclear Power Plant with five reactors of 600 MWe is under construction at Cernavoda town and in 1996 the first reactor was put in operation. The background level of tritium concentration was determined in preoperational stage. The mean values determined are: (7.4±5.5) Bq/l in air humidity, (3.1±1.0) Bq/l in water, (3.5±0.7) Bq/l in tissue water from vegetable and (4.9±1.7) Bq/l in tissue water from cereals. The transfer parameters for deposition from atmosphere on forage and crops (P 14 ), and the contamination of land and vegetation by spray irrigation water, (P 24 ) were evaluated at (29-49) and (0.90±0.27), respectively. (author)

  3. Effect of reactor conditions on MSIV [main steam isolation valves]-ATWS power level

    International Nuclear Information System (INIS)

    Diamond, D.J.

    1987-01-01

    In a boiling water reactor (BWR) when there is closure of the main steam isolation valves (MSIVs), the energy generated in the core will be transferred to the pressure suppression pool (PSP) via steam flows out of the relief valves. The pool has limited capacity as a heat sink and hence, if there is no reactor trip (an ATWS event), there is the possibility that the pool temperature may rise beyond acceptable limits. The present study was undertaken to determine how the initial reactor conditions affect the power during an MSIV-ATWS event. The time of interest is during the 20-30 minute period when it is assumed that the reactor is in a quasi-equilibrium condition with the water level and pressure fixed, natural circulation conditions and no control rod movement or significant boron in the core. The initial conditions of interest are the time during the cycle and the operating state. 4 refs., 2 tabs

  4. High impact data visualization with Power View, Power Map, and Power BI

    CERN Document Server

    Aspin, Adam

    2014-01-01

    High Impact Data Visualization with Power View, Power Map, and Power BI helps you take business intelligence delivery to a new level that is interactive, engaging, even fun, all while driving commercial success through sound decision-making. Learn to harness the power of Microsoft's flagship, self-service business intelligence suite to deliver compelling and interactive insight with remarkable ease. Learn the essential techniques needed to enhance the look and feel of reports and dashboards so that you can seize your audience's attention and provide them with clear and accurate information. Al

  5. Evaluative conditioning induces changes in sound valence

    Directory of Open Access Journals (Sweden)

    Anna C. Bolders

    2012-04-01

    Full Text Available Evaluative Conditioning (EC has hardly been tested in the auditory domain, but it is a potentially valuable research tool. In Experiment 1 we investigated whether the affective evaluation of short environmental sounds can be changed using affective words as unconditioned stimuli (US. Congruence effects on an affective priming task (APT for conditioned sounds demonstrated successful EC. Subjective ratings for sounds paired with negative words changed accordingly. In Experiment 2 we investigated whether the acquired valence remains stable after repeated presentation of the conditioned sound without the US or whether extinction occurs. The acquired affective value remained present, albeit weaker, even after 40 extinction trials. These results warrant the use of EC to study processing of short environmental sounds with acquired valence, even if this requires repeated stimulus presentations. This paves the way for studying processing of affective environmental sounds while effectively controlling low level-stimulus properties.

  6. Making fictions sound real

    DEFF Research Database (Denmark)

    Langkjær, Birger

    2010-01-01

    of sounds. Apart from an account of the kinds of sounds that typically appear in a specific genre, a genre analysis of sound may also benefit from a functionalist approach that focuses on how sounds can make both realist and non-realist aspects of genres sound real to audiences.......This article examines the role that sound plays in making fictions perceptually real to film audiences, whether these fictions are realist or non-realist in content and narrative form. I will argue that some aspects of film sound practices and the kind of experiences they trigger are related...... to basic rules of human perception, whereas others are more properly explained in relation to how aesthetic devices, including sound, are used to characterise the fiction and thereby make it perceptually real to its audience. Finally, I will argue that not all genres can be defined by a simple taxonomy...

  7. Making fictions sound real

    DEFF Research Database (Denmark)

    Langkjær, Birger

    2010-01-01

    This article examines the role that sound plays in making fictions perceptually real to film audiences, whether these fictions are realist or non-realist in content and narrative form. I will argue that some aspects of film sound practices and the kind of experiences they trigger are related...... to basic rules of human perception, whereas others are more properly explained in relation to how aesthetic devices, including sound, are used to characterise the fiction and thereby make it perceptually real to its audience. Finally, I will argue that not all genres can be defined by a simple taxonomy...... of sounds. Apart from an account of the kinds of sounds that typically appear in a specific genre, a genre analysis of sound may also benefit from a functionalist approach that focuses on how sounds can make both realist and non-realist aspects of genres sound real to audiences....

  8. Sound wave transmission (image)

    Science.gov (United States)

    When sounds waves reach the ear, they are translated into nerve impulses. These impulses then travel to the brain where they are interpreted by the brain as sound. The hearing mechanisms within the inner ear, can ...

  9. Operator performance and annunciation sounds

    International Nuclear Information System (INIS)

    Patterson, B.K.; Bradley, M.T.; Artiss, W.G.

    1997-01-01

    This paper discusses the audible component of annunciation found in typical operating power stations. The purpose of the audible alarm is stated and the psychological elements involved in the human processing of alarm sounds is explored. Psychological problems with audible annunciation are noted. Simple and more complex improvements to existing systems are described. A modern alarm system is suggested for retrofits or new plant designs. (author)

  10. Efficiency improvement of transport service by trolley buses based on the levels of their power demand

    Directory of Open Access Journals (Sweden)

    V. V. Aulin

    2014-12-01

    Full Text Available Purpose. Use efficiency improvement of trolley buses in passenger traffic based on power levels of electric energy input and terms adjustment of their maintenance. Methodology. In order to achieve this goal conformance of electric energy input by trolleybus to the transported amount of passengers taking into account characteristics of the route is offered to establish. The major indicators of the trolleybus operation are: speed of a race on lines, number of tractive motor firing, voltage and amperage in the network that were taken with accountants from a dashboard. Research results were tabulated and recorded with DVR. Along with the study of power consumption of electric energy input by a trolleybus passenger count was carried out too. Findings. The directly proportional dependence between the level of energy consumption by a trolleybus and the number of passengers for constant performance route was determined. Originality. As the criteria for evaluating the effectiveness of the trolleybus operation on the route is proposed to use the ratio between electricity consumption and number of passengers for these characteristics of the route. This is confirmed experimentally. The obtained formulas give the possibility to balance the force work and consequently the volume of energy consumption during the trolleybus movement on the rise and the descent. Practical value. The proposed criterion can be used to adjust the terms of maintenance on the individual program, that means individual maintenance (IM. Type of work performed at the IM should be determined on the basis of diagnostic data of the vehicle (V. The principles of IM were formulated: 1 the primary task is planned and preventative strategy to identify and eliminate troubleshooting and technical actions; 2 operational control of the vehicle (V technical condition on the basis of prediction of its state using the proposed criteria, that takes into account the dependence of power consumption to

  11. An Antropologist of Sound

    DEFF Research Database (Denmark)

    Groth, Sanne Krogh

    2015-01-01

    PROFESSOR PORTRAIT: Sanne Krogh Groth met Holger Schulze, newly appointed professor in Musicology at the Department for Arts and Cultural Studies, University of Copenhagen, to a talk about anthropology of sound, sound studies, musical canons and ideology.......PROFESSOR PORTRAIT: Sanne Krogh Groth met Holger Schulze, newly appointed professor in Musicology at the Department for Arts and Cultural Studies, University of Copenhagen, to a talk about anthropology of sound, sound studies, musical canons and ideology....

  12. Propagation of sound

    DEFF Research Database (Denmark)

    Wahlberg, Magnus; Larsen, Ole Næsbye

    2017-01-01

    properties can be modified by sound absorption, refraction, and interference from multi paths caused by reflections.The path from the source to the receiver may be bent due to refraction. Besides geometrical attenuation, the ground effect and turbulence are the most important mechanisms to influence...... communication sounds for airborne acoustics and bottom and surface effects for underwater sounds. Refraction becomes very important close to shadow zones. For echolocation signals, geometric attenuation and sound absorption have the largest effects on the signals....

  13. Form Follows Sound

    OpenAIRE

    Caramiaux, Baptiste; Altavilla, Alessandro; Pobiner, Scott G.; Tanaka, Atau

    2015-01-01

    Sonic interaction is the continuous relationship between user actions and sound, mediated by some technology. Because interaction with sound may be task oriented or experience-based it is important to understand the nature of action-sound relationships in order to design rich sonic interactions. We propose a participatory approach to sonic interaction design that first considers the affordances of sounds in order to imagine embodied interaction, and based on this, generates interaction models...

  14. Tracheal Sounds Acquisition Using Smartphones

    Directory of Open Access Journals (Sweden)

    Bersain A. Reyes

    2014-07-01

    Full Text Available Tracheal sounds have received a lot of attention for estimating ventilation parameters in a non-invasive way. The aim of this work was to examine the feasibility of extracting accurate airflow, and automating the detection of breath-phase onset and respiratory rates all directly from tracheal sounds acquired from an acoustic microphone connected to a smartphone. We employed the Samsung Galaxy S4 and iPhone 4s smartphones to acquire tracheal sounds from N = 9 healthy volunteers at airflows ranging from 0.5 to 2.5 L/s. We found that the amplitude of the smartphone-acquired sounds was highly correlated with the airflow from a spirometer, and similar to previously-published studies, we found that the increasing tracheal sounds’ amplitude as flow increases follows a power law relationship. Acquired tracheal sounds were used for breath-phase onset detection and their onsets differed by only 52 ± 51 ms (mean ± SD for Galaxy S4, and 51 ± 48 ms for iPhone 4s, when compared to those detected from the reference signal via the spirometer. Moreover, it was found that accurate respiratory rates (RR can be obtained from tracheal sounds. The correlation index, bias and limits of agreement were r2 = 0.9693, 0.11 (−1.41 to 1.63 breaths-per-minute (bpm for Galaxy S4, and r2 = 0.9672, 0.097 (–1.38 to 1.57 bpm for iPhone 4s, when compared to RR estimated from spirometry. Both smartphone devices performed similarly, as no statistically-significant differences were found.

  15. Power penalties for multi-level PAM modulation formats at arbitrary bit error rates

    Science.gov (United States)

    Kaliteevskiy, Nikolay A.; Wood, William A.; Downie, John D.; Hurley, Jason; Sterlingov, Petr

    2016-03-01

    There is considerable interest in combining multi-level pulsed amplitude modulation formats (PAM-L) and forward error correction (FEC) in next-generation, short-range optical communications links for increased capacity. In this paper we derive new formulas for the optical power penalties due to modulation format complexity relative to PAM-2 and due to inter-symbol interference (ISI). We show that these penalties depend on the required system bit-error rate (BER) and that the conventional formulas overestimate link penalties. Our corrections to the standard formulas are very small at conventional BER levels (typically 1×10-12) but become significant at the higher BER levels enabled by FEC technology, especially for signal distortions due to ISI. The standard formula for format complexity, P = 10log(L-1), is shown to overestimate the actual penalty for PAM-4 and PAM-8 by approximately 0.1 and 0.25 dB respectively at 1×10-3 BER. Then we extend the well-known PAM-2 ISI penalty estimation formula from the IEEE 802.3 standard 10G link modeling spreadsheet to the large BER case and generalize it for arbitrary PAM-L formats. To demonstrate and verify the BER dependence of the ISI penalty, a set of PAM-2 experiments and Monte-Carlo modeling simulations are reported. The experimental results and simulations confirm that the conventional formulas can significantly overestimate ISI penalties at relatively high BER levels. In the experiments, overestimates up to 2 dB are observed at 1×10-3 BER.

  16. Monaural adaptive mechanisms in human sound localization

    NARCIS (Netherlands)

    Wanrooij, M.M. van

    2007-01-01

    Human sound localization results primarily from the processing of binaural differences in sound level and arrival time for locations in the horizontal plane and of spectral shape cues generated by the head and pinnae for positions in the vertical plane. Both types of cues have to be weighted and

  17. Modelling Hyperboloid Sound Scattering

    DEFF Research Database (Denmark)

    Burry, Jane; Davis, Daniel; Peters, Brady

    2011-01-01

    The Responsive Acoustic Surfaces workshop project described here sought new understandings about the interaction between geometry and sound in the arena of sound scattering. This paper reports on the challenges associated with modelling, simulating, fabricating and measuring this phenomenon using...... both physical and digital models at three distinct scales. The results suggest hyperboloid geometry, while difficult to fabricate, facilitates sound scattering....

  18. Abnormal sound detection device

    International Nuclear Information System (INIS)

    Yamada, Izumi; Matsui, Yuji.

    1995-01-01

    Only components synchronized with rotation of pumps are sampled from detected acoustic sounds, to judge the presence or absence of abnormality based on the magnitude of the synchronized components. A synchronized component sampling means can remove resonance sounds and other acoustic sounds generated at a synchronously with the rotation based on the knowledge that generated acoustic components in a normal state are a sort of resonance sounds and are not precisely synchronized with the number of rotation. On the other hand, abnormal sounds of a rotating body are often caused by compulsory force accompanying the rotation as a generation source, and the abnormal sounds can be detected by extracting only the rotation-synchronized components. Since components of normal acoustic sounds generated at present are discriminated from the detected sounds, reduction of the abnormal sounds due to a signal processing can be avoided and, as a result, abnormal sound detection sensitivity can be improved. Further, since it is adapted to discriminate the occurrence of the abnormal sound from the actually detected sounds, the other frequency components which are forecast but not generated actually are not removed, so that it is further effective for the improvement of detection sensitivity. (N.H.)

  19. A three-dimensional integrated nanogenerator for effectively harvesting sound energy from the environment.

    Science.gov (United States)

    Liu, Jinmei; Cui, Nuanyang; Gu, Long; Chen, Xiaobo; Bai, Suo; Zheng, Youbin; Hu, Caixia; Qin, Yong

    2016-03-07

    An integrated triboelectric nanogenerator (ITNG) with a three-dimensional structure benefiting sound propagation and adsorption is demonstrated to more effectively harvest sound energy with improved output performance. With different multifunctional integrated layers working harmonically, it could generate a short-circuit current up to 2.1 mA, an open-circuit voltage up to 232 V and the maximum charging rate can reach 453 μC s(-1) for a 1 mF capacitor, which are 4.6 times, 2.6 times and 7.4 times the highest reported values, respectively. Further study shows that the ITNG works well under sound in a wide range of sound intensity levels (SILs) and frequencies, and its output is sensitive to the SIL and frequency of the sound, which reveals that the ITNG can act as a self-powered active sensor for real-time noise surveillance and health care. Moreover, this generator can be used to directly power the Fe(OH)3 sol electrophoresis and shows great potential as a wireless power supply in the electrochemical industry.

  20. Operating and Loading Conditions of a Three-Level Neutral-Point-Clamped Wind Power Converter Under Various Grid Faults

    DEFF Research Database (Denmark)

    Ma, Ke; Liserre, Marco; Blaabjerg, Frede

    2014-01-01

    In order to fulfill the growing demands from the grid side, full-scale power converters are becoming popular in the wind turbine system. The low-voltage ride-through (LVRT) requirements may not only cause control problems but also result in overstressed components for the power converter. However...... are analytically solved and simulated. It has been found that the operating and loading conditions of the converter under LVRT strongly depend on the types/severity values of grid voltage dips and also the chosen control algorithms. The thermal distribution among the three phases of the converter may be quite......, the thermal loading of the wind power converter under various grid faults is still not yet clarified, particularly at megawatt power level. In this paper, the impacts by three types of grid faults to a three-level neutral-point-clamped (3L-NPC) wind power converter in terms of operating and loading conditions...

  1. Experimental analysis of flexibility change with different levels of power reduction by demand response activation on thermostat controlled loads

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam; Marinelli, Mattia; Hu, Junjie

    2017-01-01

    This paper studies the flexibility available with thermostatically controlled loads (TCLs) to provide power system services by demand response (DR) activation. Although the DR activation on TCLs can provide power system ancillary services, it is important to know how long such services can...... be provided for when different levels of power reduction are imposed. The flexibility change with different levels of power reduction is tested experimentally with domestic fridges used by real customers with unknown user interaction. The investigation quantifies the flexibility of household fridges...... and the impact of DR activation in terms of deviation in the average temperature. The maximum possible power reduction with the cluster of refrigerators is 67% and the available flexibility with the cluster of refrigerators is 10%. The resulting deviation in the average temperature is 14%....

  2. Output Feedback Dissipation Control for the Power-Level of Modular High-Temperature Gas-Cooled Reactors

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2011-11-01

    Full Text Available Because of its strong inherent safety features and the high outlet temperature, the modular high temperature gas-cooled nuclear reactor (MHTGR is the chosen technology for a new generation of nuclear power plants. Such power plants are being considered for industrial applications with a wide range of power levels, thus power-level regulation is very important for their efficient and stable operation. Exploiting the large scale asymptotic closed-loop stability provided by nonlinear controllers, a nonlinear power-level regulator is presented in this paper that is based upon both the techniques of feedback dissipation and well-established backstepping. The virtue of this control strategy, i.e., the ability of globally asymptotic stabilization, is that it takes advantage of the inherent zero-state detectability property of the MHTGR dynamics. Moreover, this newly built power-level regulator is also robust towards modeling uncertainty in the control rod dynamics. If modeling uncertainty of the control rod dynamics is small enough to be omitted, then this control law can be simplified to a classical proportional feedback controller. The comparison of the control performance between the newly-built power controller and the simplified controller is also given through numerical study and theoretical analysis.

  3. Clearance of very low level radioactive waste in spanish nuclear power plants

    International Nuclear Information System (INIS)

    Alvarez Mir, F.

    2001-01-01

    According to present Spanish legislation a radioactive waste is defined as any material or waste product, without any possible planned use, that contains or is contaminated with radionuclides in concentrations or activity levels higher than those established by the Regulatory Authorities. Legally, this situation allows to develop a conventional management of very low level radioactive waste, by checking the negligibility of their radiological impact, and thus obtaining the corresponding Authorization to treat them as conventional waste. This presentation describes the clearance project of contaminated oils from spanish nuclear power plants. The on-site management includes: -) preliminary settling, centrifugation and filtration; -) oil purification; and -) radiological characterization. The off-site management includes the following operations: -) transportation to the facility where treatment is developed (dilution); -) temporary storage (decay); -) transportation to the place where final management is carried out; -) oil burning (dilution); and management of ashes and other combustion products. An annual amount of 70 m 3 /year (63 MBq) of very low contaminated oil with a specific concentration of 1 Bq/g could be disposed off. (A.C.)

  4. Dose estimation for nuclear power plant 4 accident in Taiwan at Fukushima nuclear meltdown emission level

    International Nuclear Information System (INIS)

    Tang, Mei-Ling; Tsuang, Ben-Jei; Kuo, Pei-Hsuan

    2016-01-01

    An advanced Gaussian trajectory dispersion model is used to evaluate the evacuation zone due to a nuclear meltdown at the Nuclear Power Plant 4 (NPP4) in Taiwan, with the same emission level as that occurred at Fukushima nuclear meltdown (FNM) in 2011. Our study demonstrates that a FNM emission level would pollute 9% of the island's land area with annual effective dose ≥50 mSv using the meteorological data on 11 March 2011 in Taiwan. This high dose area is also called permanent evacuation zone (denoted as PEZ). The PEZ as well as the emergency-planning zone (EPZ) are found to be sensitive to meteorological conditions on the event. In a sunny day under the dominated NE wind conditions, the EPZ can be as far as 100 km with the first 7-day dose ≥20 mSv. Three hundred sixty-five daily events using the meteorological data from 11 March 2011 to 9 March 2012 are evaluated. It is found that the mean land area of Taiwan in becoming the PEZ is 11%. Especially, the probabilities of the northern counties/cities (Keelung, New Taipei, Taipei, Taoyuan, Hsinchu City, Hsinchu County and Ilan County) to be PEZs are high, ranging from 15% in Ilan County to 51% in Keelung City. Note that the total population of the above cities/counties is as high as 10 million people. Moreover, the western valleys of the Central Mountain Range are also found to be probable being PEZs, where all of the reservoirs in western Taiwan are located. For example, the probability can be as high as 3% in the far southern-most tip of Taiwan Island in Pingtung County. This shows that the entire populations in western Taiwan can be at risk due to the shortage of clean water sources under an event at FNM emission level, especially during the NE monsoon period. - Highlights: • An advanced Gaussian-type trajectory model to evaluate the evacuation zone at Nuclear Power Plant 4 in Taiwan. • Mean land area of Taiwan in becoming the permanent evacuation zone is 11%. • The probabilities of the northern

  5. A study of radioactivity level of the cements containing fly ash of Soma power plant

    International Nuclear Information System (INIS)

    Aslan, A.; Oezer, N.; Suener, U.

    2009-01-01

    Cement is a product that is formed by grinding gypsum with clinkers resulted by burning the mixture that is obtained after mixing and grinding mainly silicium, calcium, alumina and iron oxides containing raw materials in certain proportions, to sintered degrees. When combined with water it posses binding properties. For portland cements, % 3-6 proportion gypsum (CaSO 4 .2H 2 O) in weight are added to clinkers at the grinding step in order to adjust the hydration degrees. By this way it prevents tricalcium aluminate (3CaO.Al 2 O 3 ) from rapid hardening. If ground without gypsum addition, clinkers when combined with water, harden rapidly. Additives such as fly ash, blast furnace slag, natural slag and trash possessing puzzolanic properties are also added to portland cement clinkers. At power plants, during the burning process of coals, light elements such as hydrogen and carbon are converted to their gaseous forms, and remaining ashes than become rich with uranium content. Thus fly ashes contain radioactive elements such as U-238 (Uranium), Th-232 (Thorium) and K-40 (Potassium). U-238 found in fly ash is not an intensively radioactive element at the beginning. It disintegrates naturally by losing its and particles and is transformed to some radio nuclides. Ra-226 (Radium) is the most active element among these radio nuclides and it is transformed to radon gas (Rn-222) by losing new particle. The rare gas radon and radioactive radium extremely jeopardize human health. Fly ashes when used in cements, it can lead to increase in the radioactivity level which is of prime public concern. It is therefore important to determine the radioactivity level formed in the cements and compare with the standard values. In this study, photon emissions and mechanical strength tests of C type fly ash of Soma power plant and portland cements containing this fly ash under laboratory conditions were measured. In that manner it has been examined whether fly ashes may cause some significant

  6. Improving packaging and increasing the level of integration in power electronics

    NARCIS (Netherlands)

    Popovic, J.

    2005-01-01

    The use of power electronics is growing extensively in applications such as the automotive field, lighting, power supplies, motor drives, etc. The ultimate goal is to make power electronics as transparent to the final user as possible, which means little extra cost, use of existing space and little

  7. The selection of introduced sounds to improve the soundscape in the public spaces.

    Science.gov (United States)

    Jang, Gil-Soo; Kook, Chan

    2005-01-01

    The purpose of introducing sounds is to afford a comfortable acoustic environment and to design good soundscapes. This study aims at rating the preference of subjects for the introduced sounds suitable to the public spaces and also investigates the methodology to select the sounds by subjective and objective procedures. Seventeen kinds of the introduced sounds were evaluated with nine adjectives in the presence of visual location information. Also, adequate sound levels were calculated by adjusting the volume of introduced sounds in the presence of the actual background sounds of locations and visual information. The concept of harmony with the surroundings was reviewed by analyzing the correlation among 9 adjectives which express introduced sounds. And the effectiveness of existed sound quality index was analyzed so as to select the introduced sounds quantitatively. By the evaluation of the adequate level of the introduced sounds, it is proposed that the lower introduced sound level would be better for the noisy circumstances.

  8. A note on measurement of sound pressure with intensity probes

    DEFF Research Database (Denmark)

    Juhl, Peter; Jacobsen, Finn

    2004-01-01

    be improved under a variety of realistic sound field conditions by applying a different weighting of the two pressure signals from the probe. The improved intensity probe can measure the sound pressure more accurately at high frequencies than an ordinary sound intensity probe or an ordinary sound level meter......The effect of scattering and diffraction on measurement of sound pressure with "two-microphone" sound intensity probes is examined using an axisymmetric boundary element model of the probe. Whereas it has been shown a few years ago that the sound intensity estimated with a two-microphone probe...... is reliable up to 10 kHz when using 0.5 in. microphones in the usual face-to-face arrangement separated by a 12 mm spacer, the sound pressure measured with the same instrument will typically be underestimated at high frequencies. It is shown in this paper that the estimate of the sound pressure can...

  9. Electromagnetic Sampo soundings at Olkiluoto in 2007

    International Nuclear Information System (INIS)

    Korhonen, K.; Lehtimaeki, J.

    2007-11-01

    The Geological Survey of Finland (GTK) carried out a Sampo Gefinex 400S frequency domain electromagnetic (EM) survey in the central part of the eastern Olkiluoto island. The survey comprised a total of 408 soundings; 134 of these were measurements of EM noise. The goal of the survey was to supplement previously performed soundings. The measurements of EM noise were used to analyse the influence of power lines on the soundings. A statistically significant correlation was found between EM noise and the distance between the receiver and the high-voltage power line located northeast of the research area. The high-voltage power line exerted a considerable influence on the soundings. Numerical modelling was used to evaluate the effect of a dipping layer on the interpretation of Sampo soundings, which is based on the 1-D layered earth model. The results indicate that Sampo interpretation is robust even in the case of a dipping layer, assuming that the dip of the layer is not steep, and both the transmitter and receiver are located above the layer. The interpretations of the soundings indicate three conducting layers. There appear to be two layers of significant conductivity above the depth of 600 m. These layers may be indications of sulphide and/or graphite rich layers. Furthermore, a deeper conducting layer below the depth of 600 m was also indicated by the interpretations. This layer may indicate deep saline groundwater. (orig.)

  10. 78 FR 13869 - Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy...

    Science.gov (United States)

    2013-03-01

    ...-123-LNG; 12-128-NG; 12-148-NG; 12- 158-NG] Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; Puget Sound Energy, Inc.; CE FLNG, LLC; Consolidated...-NG Puget Sound Energy, Inc Order granting long- term authority to import/export natural gas from/to...

  11. Simulation of Sound Waves Using the Lattice Boltzmann Method for Fluid Flow: Benchmark Cases for Outdoor Sound Propagation.

    Science.gov (United States)

    Salomons, Erik M; Lohman, Walter J A; Zhou, Han

    2016-01-01

    Propagation of sound waves in air can be considered as a special case of fluid dynamics. Consequently, the lattice Boltzmann method (LBM) for fluid flow can be used for simulating sound propagation. In this article application of the LBM to sound propagation is illustrated for various cases: free-field propagation, propagation over porous and non-porous ground, propagation over a noise barrier, and propagation in an atmosphere with wind. LBM results are compared with solutions of the equations of acoustics. It is found that the LBM works well for sound waves, but dissipation of sound waves with the LBM is generally much larger than real dissipation of sound waves in air. To circumvent this problem it is proposed here to use the LBM for assessing the excess sound level, i.e. the difference between the sound level and the free-field sound level. The effect of dissipation on the excess sound level is much smaller than the effect on the sound level, so the LBM can be used to estimate the excess sound level for a non-dissipative atmosphere, which is a useful quantity in atmospheric acoustics. To reduce dissipation in an LBM simulation two approaches are considered: i) reduction of the kinematic viscosity and ii) reduction of the lattice spacing.

  12. Sound wave contours around wind turbine arrays

    International Nuclear Information System (INIS)

    Van Beek, A.; Van Blokland, G.J.

    1993-02-01

    Noise pollution is an important factor in selecting suitable sites for wind turbines in order to realize 1000 MW of wind power as planned by the Dutch government for the year 2000. Therefore an accurate assessment of wind turbine noise is important. The amount of noise pollution from a wind turbine depends on the wind conditions. An existing standard method to assess wind turbine noise is supplemented and adjusted. In the first part of the investigation the method was developed and applied for a solitary sound source. In the second part attention is paid to the use of the method for wind turbine arrays. It appears that the adjusted method results in a shift of the contours of the permitted noise level. In general the contours are 15-25% closer to the wind farm, which means that the minimal permitted distance between houses and wind turbine arrays can be reduced. 14 figs., 1 tab., 4 appendices, 7 refs

  13. Analysis of environmental sounds

    Science.gov (United States)

    Lee, Keansub

    consumer videos in conjunction with user studies. We model the soundtrack of each video, regardless of its original duration, as a fixed-sized clip-level summary feature. For each concept, an SVM-based classifier is trained according to three distance measures (Kullback-Leibler, Bhattacharyya, and Mahalanobis distance). Detecting the time of occurrence of a local object (for instance, a cheering sound) embedded in a longer soundtrack is useful and important for applications such as search and retrieval in consumer video archives. We finally present a Markov-model based clustering algorithm able to identify and segment consistent sets of temporal frames into regions associated with different ground-truth labels, and at the same time to exclude a set of uninformative frames shared in common from all clips. The labels are provided at the clip level, so this refinement of the time axis represents a variant of Multiple-Instance Learning (MIL). Quantitative evaluation shows that the performance of our proposed approaches tested on the 60h personal audio archives or 1900 YouTube video clips is significantly better than existing algorithms for detecting these useful concepts in real-world personal audio recordings.

  14. Model for the techno-economic analysis of common work of wind power and CCGT power plant to offer constant level of power in the electricity market

    Directory of Open Access Journals (Sweden)

    Tomsic Z.

    2017-01-01

    For calculation purposes, the following parameters are necessary to know in order to be able to economically evaluate changes in the start-up process: ramp up and down rate, time of start time reduction, fuel mass flow during start, electricity production during start, variable cost of start-up process, cost and charges for life time consumption for each start and start type, remuneration during start up time regarding expected or unexpected starts, the cost and revenues for balancing energy (important when participating in electricity market, and the cost or revenues for CO2-certificates. Main motivation for this analysis is to investigate possibilities to participate on power exchanges by offering continues guarantied power from wind plants by backing-up them with CCGT power plant.

  15. An Artificial Neural Network Compensated Output Feedback Power-Level Control for Modular High Temperature Gas-Cooled Reactors

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2014-02-01

    Full Text Available Small modular reactors (SMRs could be beneficial in providing electricity power safely and also be viable for applications such as seawater desalination and heat production. Due to its inherent safety features, the modular high temperature gas-cooled reactor (MHTGR has been seen as one of the best candidates for building SMR-based nuclear power plants. Since the MHTGR dynamics display high nonlinearity and parameter uncertainty, it is necessary to develop a nonlinear adaptive power-level control law which is not only beneficial to the safe, stable, efficient and autonomous operation of the MHTGR, but also easy to implement practically. In this paper, based on the concept of shifted-ectropy and the physically-based control design approach, it is proved theoretically that the simple proportional-differential (PD output-feedback power-level control can provide asymptotic closed-loop stability. Then, based on the strong approximation capability of the multi-layer perceptron (MLP artificial neural network (ANN, a compensator is established to suppress the negative influence caused by system parameter uncertainty. It is also proved that the MLP-compensated PD power-level control law constituted by an experientially-tuned PD regulator and this MLP-based compensator can guarantee bounded closed-loop stability. Numerical simulation results not only verify the theoretical results, but also illustrate the high performance of this MLP-compensated PD power-level controller in suppressing the oscillation of process variables caused by system parameter uncertainty.

  16. A High-Power-Density Single-Phase Rectifier Based on Three-Level Neutral-Point Clamped Circuits

    Directory of Open Access Journals (Sweden)

    Tao Zhou

    2017-05-01

    Full Text Available A single-phase three-level converter is suitable for medium-power applications, with an interface voltage that is higher than that of a traditional two-level configuration. The three-level neutral-point clamped converter is adopted using four switches in each bridge arm, which, compared to a two-level rectifier, leads to less voltage stress, a lower switching frequency, and switching loss on switches. The transient current control strategy is designed to control the active power. The single-phase space vector pulse width modulation (SVPWM with a voltage balance strategy is designed to solve the neutral point voltage fluctuation problem and keep the dc-link voltage stable. A 1.3 kW high-power-density prototype based on SiC MOSFET was built and tested. The experimental results verified the high performance of steady-state and dynamic responses.

  17. Levelling the playing field? The influence of national wind power planning instruments on conflicts of interests in a Swedish county

    International Nuclear Information System (INIS)

    Bergek, Anna

    2010-01-01

    Slow and complicated wind power planning and permitting procedures have been a large obstacle for wind power diffusion in Sweden and other countries. This paper complements previous siting-oriented literature with a planning perspective on these problems. The focus is two national planning instruments implemented in Sweden in the early 2000s: a national planning target and an appointment of areas of national interest for wind power. The paper identifies different types of conflicts of interest related to wind power - in addition to the conflict between wind power as a national public interest and various local private interests - and analyses the impact of the national planning instruments on the handling of these conflicts in the land-use planning process in the County of Ostergoetland. The analysis shows that the planning target actually made local planning officials even more inclined to treat wind power as a private rather than a public interest and that the method used to identify areas of national interest of wind power forced wind power to compete with the combined strengths of all other public interest. The planning instruments thus left wind power to fight an uphill battle rather than to meet other interests face-to-face on a level playing field.

  18. Using science soundly: The Yucca Mountain standard

    International Nuclear Information System (INIS)

    Fri, R.W.

    1995-01-01

    Using sound science to shape government regulation is one of the most hotly argued topics in the ongoing debate about regulatory reform. Even though no one advaocates using unsound science, the belief that even the best science will sweep away regulatory controversy is equally foolish. As chair of a National Research Council (NRC) committee that studied the scientific basis for regulating high-level nuclear waste disposal, the author learned that science alone could resolve few of the key regulatory questions. Developing a standard that specifies a socially acceptable limit on the human health effects of nuclear waste releases involves many decisions. As the NRC committee learned in evaluating the scientific basis for the Yucca Mountain standard, a scientifically best decision rarely exists. More often, science can only offer a useful framework and starting point for policy debates. And sometimes, science's most helpful contribution is to admit that it has nothing to say. The Yucca mountain study clearly illustrates that excessive faith in the power of science is more likely to produce messy frustration than crisp decisions. A better goal for regulatory reform is the sound use of science to clarify and contain the inevitable policy controversy

  19. Comparison of Mental Toughness and Power Test Performances in High-Level Kickboxers by Competitive Success.

    Science.gov (United States)

    Slimani, Maamer; Miarka, Bianca; Briki, Walid; Cheour, Foued

    2016-06-01

    Kickboxing is a high-intensity intermittent striking combat sport, which is characterized by complex skills and tactical key actions with short duration. The present study compared and verified the relationship between mental toughness (MT), countermovement jump (CMJ) and medicine ball throw (MBT) power tests by outcomes of high-level kickboxers during National Championship. Thirty two high-level male kickboxers (winner = 16 and loser = 16: 21.2 ± 3.1 years, 1.73 ± 0.07 m, and 70.2 ± 9.4 kg) were analyzed using the CMJ, MBT tests and sports mental toughness questionnaire (SMTQ; based in confidence, constancy and control subscales), before the fights of the 2015 national championship (16 bouts). In statistical analysis, Mann-Withney test and a multiple linear regression were used to compare groups and to observe relationships, respectively, P ≤ 0.05. The present results showed significant differences between losers vs. winners, respectively, of total MT (7(7;8) vs. 11(10.2;11), confidence (3(3;3) vs. 4(4;4)), constancy (2(2;2) vs. 3(3;3)), control (2(2;3) vs. 4(4;4)) subscales and MBT (4.1(4;4.3) vs. 4.6(4.4;4.8)). The multiple linear regression showed a strong associations between MT results and outcome (r = 0.89), MBT (r = 0.84) and CMJ (r = 0.73). The findings suggest that MT will be more predictive of performance in those sports and in the outcome of competition.

  20. Comparison of Mental Toughness and Power Test Performances in High-Level Kickboxers by Competitive Success

    Science.gov (United States)

    Slimani, Maamer; Miarka, Bianca; Briki, Walid; Cheour, Foued

    2016-01-01

    Background Kickboxing is a high-intensity intermittent striking combat sport, which is characterized by complex skills and tactical key actions with short duration. Objectives The present study compared and verified the relationship between mental toughness (MT), countermovement jump (CMJ) and medicine ball throw (MBT) power tests by outcomes of high-level kickboxers during National Championship. Materials and Methods Thirty two high-level male kickboxers (winner = 16 and loser = 16: 21.2 ± 3.1 years, 1.73 ± 0.07 m, and 70.2 ± 9.4 kg) were analyzed using the CMJ, MBT tests and sports mental toughness questionnaire (SMTQ; based in confidence, constancy and control subscales), before the fights of the 2015 national championship (16 bouts). In statistical analysis, Mann-Withney test and a multiple linear regression were used to compare groups and to observe relationships, respectively, P ≤ 0.05. Results The present results showed significant differences between losers vs. winners, respectively, of total MT (7(7;8) vs. 11(10.2;11), confidence (3(3;3) vs. 4(4;4)), constancy (2(2;2) vs. 3(3;3)), control (2(2;3) vs. 4(4;4)) subscales and MBT (4.1(4;4.3) vs. 4.6(4.4;4.8)). The multiple linear regression showed a strong associations between MT results and outcome (r = 0.89), MBT (r = 0.84) and CMJ (r = 0.73). Conclusions The findings suggest that MT will be more predictive of performance in those sports and in the outcome of competition. PMID:27625755

  1. {sup 129}I level in seawater near a nuclear power plant determined by accelerator mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    He Chaohui, E-mail: hechaohui@mail.xjtu.edu.c [School of Nuclear Science and Technology, Xi' an JiaoTong University, No. 28 Xianning West Road, Xi' an, Shaanxi 710049 (China); Xi' an AMS center, No. 99 Yanxiang Road, Yanta Zone, Xi' an, Shaanxi 710054 (China); Hou Xiaolin [State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi' an 710075 (China); Xi' an AMS center, No. 99 Yanxiang Road, Yanta Zone, Xi' an, Shaanxi 710054 (China); Zhao Yaolin; Wang Zhiwen; Li Huaibin [School of Nuclear Science and Technology, Xi' an JiaoTong University, No. 28 Xianning West Road, Xi' an, Shaanxi 710049 (China); Xi' an AMS center, No. 99 Yanxiang Road, Yanta Zone, Xi' an, Shaanxi 710054 (China); Chen Ning; Liu Qi; Zhang Luyuan [State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi' an 710075 (China); Xi' an AMS center, No. 99 Yanxiang Road, Yanta Zone, Xi' an, Shaanxi 710054 (China); Luo Maoyi [School of Nuclear Science and Technology, Xi' an JiaoTong University, No. 28 Xianning West Road, Xi' an, Shaanxi 710049 (China); Xi' an AMS center, No. 99 Yanxiang Road, Yanta Zone, Xi' an, Shaanxi 710054 (China); Liang Wangguo [School of Nuclear Science and Technology, Xi' an JiaoTong University, No. 28 Xianning West Road, Xi' an, Shaanxi 710049 (China); State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi' an 710075 (China); Xi' an AMS center, No. 99 Yanxiang Road, Yanta Zone, Xi' an, Shaanxi 710054 (China); Fan Yukun; Zhao Xiaolei [State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi' an 710075 (China); Xi' an AMS center, No. 99 Yanxiang Road, Yanta Zone, Xi' an, Shaanxi 710054 (China)

    2011-03-11

    {sup 129}I concentration in the seawater samples near a nuclear power plant was determined in the Xi'an Accelerator Mass Spectrometer (AMS) Center. Isotope dilution method was used via addition of excessive amount of stable iodine ({sup 127}I) in the sample before separation, and iodine in the seawater was separated by solvent extraction, and the back extracted iodine in iodide form was precipitated as AgI, which was used as AMS target for {sup 129}I measurement. {sup 125}I tracer was added to monitor the recovery of iodine in the whole separation process. {sup 129}I/{sup 127}I ratios in the prepared target were determined by AMS. The concentration of {sup 127}I in seawater samples was determined by inductively coupled plasma mass spectrometry. The results show that the {sup 129}I/{sup 127}I atomic ratios in the seawater range from 8.29x10{sup -11} to 9.45x10{sup -10}, approximately one order of magnitude higher than that in seaweed collected in the pre-nuclear era, but fall in the environmental level of global fallout.

  2. Analysis for low and intermediate level radioactive waste disposal of AP1000 nuclear power in China

    International Nuclear Information System (INIS)

    Yang Bin; Ren Li; Hua Wei; Ma Xiaoqiang; Ma Ruoxia; Fang Xianghong

    2014-01-01

    AP1000 nuclear power is adopted in Sanmen Nuclear Power Plant, Zhejiang province and Haiyang Nuclear Power Plant, Shandong province. The filter and resin generated by the operation of nuclear power plants are handled by cement cured process and compression technology in Sanmen Nuclear Power Plant, while they are loaded in polyethylene HIC in Haiyang Nuclear Power Plant. At present, there were not engineering practice for dispose polyethylene HIC in China. The document discusses three disposal options of polyethylene HIC: one is that polyethylene HIC placed in over pack, another is that polyethylene HIC mixed with other drum, the third is that polyethylene HIC placed in disposal unit which is divided into small units. (authors)

  3. Teaching about energy use at the university level as a way to discuss nuclear power

    International Nuclear Information System (INIS)

    Donev, J.M.K.C.

    2011-01-01

    Alberta is considering getting a nuclear power plant. University science departments can play a significant role in educating the public about various aspects of nuclear power, and electricity usage in general. This paper discusses a novel class on energy production, use and distribution. This large lecture course has 100 students who have little to no technical training in energy. By teaching about energy issues, students become more interested nuclear power as part of the energy production portfolio. (author)

  4. Heating power at room and building levels in passive houses and low-energy buildings

    OpenAIRE

    Rinholm, Jonas Myrberg

    2015-01-01

    This master thesis investigates the Norwegian standard for calculating necessary power demand, NS-EN 12831:2003- Varmesystemer i bygninger - Metode for beregning av dimensjonerende effektbehov. In that context, it is also investigated how power demand affects heating systems financially and environmentally, but also in terms of comfort and indoor air quality. Improved energy efficiency are leading to a reduction in the power demand for heating purposes in buildings. However, there are few...

  5. Heart sound cancellation from lung sound recordings using time-frequency filtering.

    Science.gov (United States)

    Pourazad, M T; Moussavi, Z; Thomas, G

    2006-03-01

    During lung sound recordings, heart sounds (HS) interfere with clinical interpretation of lung sounds over the low frequency components which is significant especially at low flow rates. Hence, it is desirable to cancel the effect of HS on lung sound records. In this paper, a novel HS cancellation method is presented. This method first localizes HS segments using multiresolution decomposition of the wavelet transform coefficients, then removes those segments from the original lung sound record and estimates the missing data via a 2D interpolation in the time-frequency (TF) domain. Finally, the signal is reconstructed into the time domain. To evaluate the efficiency of the TF filtering, the average power spectral density (PSD) of the original lung sound segments with and without HS over four frequency bands from 20 to 300 Hz were calculated and compared with the average PSD of the filtered signals. Statistical tests show that there is no significant difference between the average PSD of the HS-free original lung sounds and the TF-filtered signal for all frequency bands at both low and medium flow rates. It was found that the proposed method successfully removes HS from lung sound signals while preserving the original fundamental components of the lung sounds.

  6. Early Experiences with Node-Level Power Capping on the Cray XC40 Platform

    Energy Technology Data Exchange (ETDEWEB)

    Pedretti, Kevin; Olivier, Stephen Lecler; Ferreira, Kurt Brian; Shipman, Galen; Shu, Wei

    2015-10-01

    Power consumption of extreme-scale supercomputers has become a key performance bottleneck. Yet current practices do not leverage power management opportunities, instead running at ''maximum power''. This is not sustainable. Future systems will need to manage power as a critical resource, directing where it has greatest benefit. Power capping is one mechanism for managing power budgets, however its behavior is not well understood. This paper presents an empirical evaluation of several key HPC workloads running under a power cap on a Cray XC40 system, and provides a comparison of this technique with p-state control, demonstrating the performance differences of each. These results show: 1. Maximum performance requires ensuring the cap is not reached; 2. Performance slowdown under a cap can be attributed to cascading delays which result in unsynchronized performance variability across nodes; and, 3. Due to lag in reaction time, considerable time is spent operating above the set cap. This work provides a timely and much needed comparison of HPC application performance under a power cap and attempts to enable users and system administrators to understand how to best optimize application performance on power-constrained HPC systems.

  7. Long-term, global-scale statistics of sound propagation.

    Science.gov (United States)

    Cheinet, Sylvain

    2014-05-01

    The near-surface sound levels emitted due to a point source show a large variability caused by sound propagation through changing meteorological conditions. To assess this variability, this study uses a numerical model of sound propagation which accounts for ground reflection, atmospheric refraction, and turbulence effects. The atmospheric inputs to the model-including turbulence-are calculated from Numerical Weather Prediction data. The method is used to investigate the relative sound levels at a range of 1.5 km from a 40 Hz sound source. The outstanding diversity of sound propagation conditions is illustrated over the globe. Over the long term, the sound propagation climates at selected sites are found to be modulated by the dominant wind regimes, the seasonal and diurnal cycles. The explored sensitivities stress the need for a careful assessment of sound scattering by turbulence and absorption by the surface.

  8. Sounds like Team Spirit

    Science.gov (United States)

    Hoffman, Edward

    2002-01-01

    trying to improve on what they've done before. Second, success in any endeavor stems from people who know how to interpret a composition to sound beautiful when played in a different style. For Knowledge Sharing to work, it must be adapted, reinterpreted, shaped and played with at the centers. In this regard, we've been blessed with another crazy, passionate, inspired artist named Claire Smith. Claire has turned Ames Research Center in California into APPL-west. She is so good and committed to what she does that I just refer people to her whenever they have questions about implementing project management development at the field level. Finally, any great effort requires talented people working behind the scenes, the people who formulate a business approach and know how to manage the money so that the music gets heard. I have known many brilliant and creative people with a ton of ideas that never take off due to an inability to work the business. Again, the Knowledge Sharing team has been fortunate to have competent and passionate people, specifically Tony Maturo and his procurement team at Goddard Space Flight Center, to make sure the process is in place to support the effort. This kind of support is every bit as crucial as the activity itself, and the efforts and creativity that go into successful procurement and contracting is a vital ingredient of this successful team.

  9. Sound a very short introduction

    CERN Document Server

    Goldsmith, Mike

    2015-01-01

    Sound is integral to how we experience the world, in the form of noise as well as music. But what is sound? What is the physical basis of pitch and harmony? And how are sound waves exploited in musical instruments? Sound: A Very Short Introduction looks at the science of sound and the behaviour of sound waves with their different frequencies. It also explores sound in different contexts, covering the audible and inaudible, sound underground and underwater, acoustic and electronic sound, and hearing in humans and animals. It concludes with the problem of sound out of place—noise and its reduction.

  10. The Textile Form of Sound

    DEFF Research Database (Denmark)

    Bendixen, Cecilie

    of sound. This issue is a part of a Ph.D. study at The Danish Design School in Copenhagen. Sound diffusion in architecture is a complex phenomenon. From the sound source the sound spreads in all directions as a sphere of wave fronts. When the sound is reflected from room boundaries or furniture, complex......Sound is a part of architecture, and sound is complex. Upon this, sound is invisible. How is it then possible to design visual objects that interact with the sound? This paper addresses the problem of how to get access to the complexity of sound and how to make textile material revealing the form...

  11. 47 CFR 73.322 - FM stereophonic sound transmission standards.

    Science.gov (United States)

    2010-10-01

    ... modulation levels apply: (i) When a signal exists in only one channel of a two channel (biphonic) sound... 47 Telecommunication 4 2010-10-01 2010-10-01 false FM stereophonic sound transmission standards... SERVICES RADIO BROADCAST SERVICES FM Broadcast Stations § 73.322 FM stereophonic sound transmission...

  12. The intrusiveness of sound: Laboratory findings and their implications for noise abatement.

    Science.gov (United States)

    Hughes, Robert; Jones, Dylan M.

    2001-01-01

    Environmental policy with regard to noise abatement has traditionally only considered whether the noise levels in a given setting are high enough to be deemed a source of annoyance, disturbance, or threat to well being. However, laboratory studies using both simple and more complex work-related tasks have shown that task-irrelevant sound, regardless of its intensity, intrudes upon cognitive processing and disrupts performance substantially; furthermore, its damaging effect does not diminish with repeated exposure to the sound over time. For tasks that require short-term memory processing (particularly the short-term maintenance of order information) sound assumes disruptive power if it is acoustically varying over its time course. However, other properties of sound (e.g., the semanticity of speech) can incur an additional cost if the primary task necessitates or tends to evoke the extraction of meaning. It will be argued that interference in each case is explained by reference to a conflict between two concurrent mental processes; that being demanded by the task and that being involuntarily applied to properties of the sound. Such harmful effects, as well as having direct consequences for the general well-being of those working in noisy environments, may have far reaching consequences for health insofar as extraneous sound is a feature of many safety-critical work settings. Implications for noise abatement policy are highlighted.

  13. Sound energy harvesting using a doubly coiled-up acoustic metamaterial cavity

    Science.gov (United States)

    Sun, Kyung Ho; Kim, Jae Eun; Kim, Jedo; Song, Kyungjun

    2017-07-01

    A new sound energy harvesting system that comprises an acoustic metastructure and a double-clamped piezoelectric bimorph plate is presented. A subwavelength-scale acoustic metastructure is specially designed by utilizing a doubly coiled-up configuration for the strong confinement of the sound energy inside the acoustic metamaterial cavity in the low frequency range. The amplified sound pressure in the acoustic metamaterial cavity then substantially increases the vibratory motions of the piezoelectric bimorph plate. For the purpose of generating more electricity from the sound, the resonant frequency of the acoustic metamaterial cavity is tuned to the fundamental frequency of the piezoelectric bimorph plate. The numerical and experiment results show that the proposed sound energy harvesting system increase a sound pressure level (SPL) by up to ∼16 dB, and yields an output voltage that is 6.32 times higher than that of the conventional piezoelectric energy harvesting plate. For the incident SPL of 100 dB, the maximum output power is measured as approximately 0.345 μW at a resonant frequency of 600 Hz.

  14. Sound Insulation between Dwellings

    DEFF Research Database (Denmark)

    Rasmussen, Birgit

    2011-01-01

    Regulatory sound insulation requirements for dwellings exist in more than 30 countries in Europe. In some countries, requirements have existed since the 1950s. Findings from comparative studies show that sound insulation descriptors and requirements represent a high degree of diversity...... and initiate – where needed – improvement of sound insulation of new and existing dwellings in Europe to the benefit of the inhabitants and the society. A European COST Action TU0901 "Integrating and Harmonizing Sound Insulation Aspects in Sustainable Urban Housing Constructions", has been established and runs...... 2009-2013. The main objectives of TU0901 are to prepare proposals for harmonized sound insulation descriptors and for a European sound classification scheme with a number of quality classes for dwellings. Findings from the studies provide input for the discussions in COST TU0901. Data collected from 24...

  15. A Comprehensive Investigation on the Short Circuit Performance of MW-level IGBT Power Modules

    DEFF Research Database (Denmark)

    Wu, Rui; Reigosa, Paula Diaz; Iannuzzo, Francesco

    2015-01-01

    This paper investigates the short circuit performance of commercial 1.7 kV / 1 kA IGBT power modules by means of a 6 kA Non-Destructive-Tester. A mismatched current distribution among the parallel chips has been observed, which can reduce the short circuit capability of the IGBT power module unde...

  16. Coherent Power Analysis in Multi-Level Studies Using Design Parameters from Surveys

    Science.gov (United States)

    Rhoads, Christopher

    2016-01-01

    Current practice for conducting power analyses in hierarchical trials using survey based ICC and effect size estimates may be misestimating power because ICCs are not being adjusted to account for treatment effect heterogeneity. Results presented in Table 1 show that the necessary adjustments can be quite large or quite small. Furthermore, power…

  17. Design of power converter in DFIG wind turbine with enhanced system-level reliability

    DEFF Research Database (Denmark)

    Zhou, Dao; Zhang, Guanguan; Blaabjerg, Frede

    2017-01-01

    With the increasing penetration of wind power, reliable and cost-effective wind energy production are of more and more importance. As one of the promising configurations, the doubly-fed induction generator based partial-scale wind power converter is still dominating in the existing wind farms, an...

  18. System-level Reliability Assessment of Power Stage in Fuel Cell Application

    DEFF Research Database (Denmark)

    Zhou, Dao; Wang, Huai; Blaabjerg, Frede

    2016-01-01

    High efficient and less pollutant fuel cell stacks are emerging and strong candidates of the power solution used for mobile base stations. In the application of the backup power, the availability and reliability hold the highest priority. This paper considers the reliability metrics from...

  19. Sound absorption of snow

    OpenAIRE

    Maysenhölder, W.; Schneebeli, M.; Zhou, X.; Zhang, T.; Heggli, M.

    2008-01-01

    Recently fallen snow possesses good sound-absorbing properties. This fact is well-known and confirmed by measurements. Is the filigree structure of snowflakes decisive? In principle we know that the sound-absorbing capacity of a porous material is dependent on its structure. But until now the question as to which structural characteristics are significant has been insufficiently answered. Detailed investigations of snow are to explain this fact by precise measurements of the sound absorption,...

  20. Possibilities of psychoacoustics to determine sound quality

    Science.gov (United States)

    Genuit, Klaus

    For some years, acoustic engineers have increasingly become aware of the importance of analyzing and minimizing noise problems not only with regard to the A-weighted sound pressure level, but to design sound quality. It is relatively easy to determine the A-weighted SPL according to international standards. However, the objective evaluation to describe subjectively perceived sound quality - taking into account psychoacoustic parameters such as loudness, roughness, fluctuation strength, sharpness and so forth - is more difficult. On the one hand, the psychoacoustic measurement procedures which are known so far have yet not been standardized. On the other hand, they have only been tested in laboratories by means of listening tests in the free-field and one sound source and simple signals. Therefore, the results achieved cannot be transferred to complex sound situations with several spatially distributed sound sources without difficulty. Due to the directional hearing and selectivity of human hearing, individual sound events can be selected among many. Already in the late seventies a new binaural Artificial Head Measurement System was developed which met the requirements of the automobile industry in terms of measurement technology. The first industrial application of the Artificial Head Measurement System was in 1981. Since that time the system was further developed, particularly by the cooperation between HEAD acoustics and Mercedes-Benz. In addition to a calibratable Artificial Head Measurement System which is compatible with standard measurement technologies and has transfer characteristics comparable to human hearing, a Binaural Analysis System is now also available. This system permits the analysis of binaural signals regarding physical and psychoacoustic procedures. Moreover, the signals to be analyzed can be simultaneously monitored through headphones and manipulated in the time and frequency domain so that those signal components being responsible for noise

  1. Numerical simulation of aerodynamic sound radiated from a two-dimensional airfoil

    OpenAIRE

    飯田, 明由; 大田黒, 俊夫; 加藤, 千幸; Akiyoshi, Iida; Toshio, Otaguro; Chisachi, Kato; 日立機研; 日立機研; 東大生研; Mechanical Engineering Research Laboratory, Hitachi Ltd.; Mechanical Engineering Research Laboratory, Hitachi Ltd.; University of Tokyo

    2000-01-01

    An aerodynamic sound radiated from a two-dimensional airfoil has been computed with the Lighthill-Curle's theory. The predicted sound pressure level is agreement with the measured one. Distribution of vortex sound sources is also estimated based on the correlation between the unsteady vorticity fluctuations and the aerodynamic sound. The distribution of vortex sound source reveals that separated shear layers generate aerodynamic sound. This result is help to understand noise reduction method....

  2. Vulnerability of US thermoelectric power generation to climate change when incorporating state-level environmental regulations

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Lu; Hejazi, Mohamad; Li, Hongyi; Forman, Barton; Zhang, Xiao

    2017-07-10

    This study explores the interactions between climate and thermoelectric generation in the U.S. by coupling an Earth System Model with a thermoelectric power generation model. We validated model simulations of power production for selected power plants (~44% of existing thermoelectric capacity) against reported values. In addition, we projected future usable capacity for existing power plants under two different climate change scenarios. Results indicate that climate change alone may reduce average thermoelectric generating capacity by 2%-3% by the 2060s. Reductions up to 12% are expected if environmental requirements are enforced without waivers for thermal variation. This study concludes that the impact of climate change on the U.S. thermoelectric power system is less than previous estimates due to an inclusion of a spatially-disaggregated representation of environmental regulations and provisional variances that temporarily relieve power plants from permit requirements. This work highlights the significance of accounting for legal constructs in which the operation of power plants are managed, and underscores the effects of provisional variances in addition to environmental requirements.

  3. Community organizing practices in a globalizing era: building power for health equity at the community level.

    Science.gov (United States)

    Speer, Paul W; Tesdahl, Eric A; Ayers, Jeanne F

    2014-01-01

    In the postindustrial era, global economic processes have constrained the ability of local agencies, service providers, and civic groups to respond to systemic challenges in public health. Community health psychology can benefit by focusing on interventions through mediating structures that develop innovative methods of leveraging power in the context of globalizing economic forces. Promising methods include careful analysis of power within targeted policy domains and developing strategic alliances with others, so as to exercise social power to affect policy change. The case of ISAIAH, an organizing group based in Minnesota, illustrates innovative avenues for intervention in the context of globalization.

  4. Use of Three-Level Power Converters in Wind-Driven Permanent-Magnet Synchronous Generators with Unbalanced Loads

    Directory of Open Access Journals (Sweden)

    Ming-Hung Chen

    2015-06-01

    Full Text Available This paper describes the design and implementation of three-level power converters for wind-driven permanent-magnet synchronous generators with unbalanced loads. To increase voltage stress and reduce current harmonics in the electrical power generated by a wind generator, a three-phase, three-level rectifier is used. Because a synchronous rotating frame is used on the AC-input side, the use of a neutral-point-clamped controller is proposed to increase the power factor to unity and reduce current harmonics. Furthermore, a novel six-leg inverter is proposed for transferring energy from the DC voltage to a three-phase, four-wire AC source with a constant voltage and a constant frequency. The power converters also contain output transformers and filters for power buffering and filtering, respectively. All three output phase voltages are fed back to control the inverter output during load variations. A digital signal processor is used as the core control device for implementing a 1.5 kV, 75 kW drive system. Experimental data show that the power factor is successfully increased to unity and the total current harmonic distortion is 3.2% on the AC-input side. The entire system can attain an efficiency of 91%, and the voltage error between the upper and lower capacitors is approximately zero. Experimental results that confirm the high performance of the proposed system are presented.

  5. Pulsed low-level infrared laser alters mRNA levels from muscle repair genes dependent on power output in Wistar rats

    Science.gov (United States)

    Trajano, L. A. S. N.; Trajano, E. T. L.; Thomé, A. M. C.; Sergio, L. P. S.; Mencalha, A. L.; Stumbo, A. C.; Fonseca, A. S.

    2017-10-01

    Satellite cells are present in skeletal muscle functioning in the repair and regeneration of muscle injury. Activation of these cells depends on the expression of myogenic factor 5 (Myf5), myogenic determination factor 1(MyoD), myogenic regulatory factor 4 (MRF4), myogenin (MyoG), paired box transcription factors 3 (Pax3), and 7 (Pax7). Low-level laser irradiation accelerates the repair of muscle injuries. However, data from the expression of myogenic factors have been controversial. Furthermore, the effects of different laser beam powers on the repair of muscle injuries have been not evaluated. The aim of this study was to evaluate the effects of low-level infrared laser at different powers and in pulsed emission mode on the expression of myogenic regulatory factors and on Pax3 and Pax7 in injured skeletal muscle from Wistar rats. Animals that underwent cryoinjury were divided into three groups: injury, injury laser 25 Mw, and injury laser 75 mW. Low-level infrared laser irradiation (904 nm, 3 J cm-2, 5 kHz) was carried out at 25 and 75 mW. After euthanasia, skeletal muscle samples were withdrawn and the total RNA was extracted for the evaluation of mRNA levels from the MyoD, MyoG, MRF4, Myf5, Pax3, and Pax7 gene. Pax 7 mRNA levels did not alter, but Pax3 mRNA levels increased in the injured and laser-irradiated group at 25 mW. MyoD, MyoG, and MYf5 mRNA levels increased in the injured and laser-irradiated animals at both powers, and MRF4 mRNA levels decreased in the injured and laser-irradiated group at 75 mW. In conclusion, exposure to pulsed low-level infrared laser, by power-dependent effect, could accelerate the muscle repair process altering mRNA levels from paired box transcription factors and myogenic regulatory factors.

  6. Demand response strategy management with active and reactive power incentive in the smart grid: a two-level optimization approach

    Directory of Open Access Journals (Sweden)

    Ryuto Shigenobu

    2017-05-01

    Full Text Available High penetration of distributed generators (DGs using renewable energy sources (RESs is raising some important issues in the operation of modern po­wer system. The output power of RESs fluctuates very steeply, and that include uncertainty with weather conditions. This situation causes voltage deviation and reverse power flow. Several methods have been proposed for solving these problems. Fundamentally, these methods involve reactive power control for voltage deviation and/or the installation of large battery energy storage system (BESS at the interconnection point for reverse power flow. In order to reduce the installation cost of static var compensator (SVC, Distribution Company (DisCo gives reactive power incentive to the cooperating customers. On the other hand, photovoltaic (PV generator, energy storage and electric vehicle (EV are introduced in customer side with the aim of achieving zero net energy homes (ZEHs. This paper proposes not only reactive power control but also active power flow control using house BESS and EV. Moreover, incentive method is proposed to promote participation of customers in the control operation. Demand response (DR system is verified with several DR menu. To create profit for both side of DisCo and customer, two level optimization approach is executed in this research. Mathematical modeling of price elasticity and detailed simulations are executed by case study. The effectiveness of the proposed incentive menu is demonstrated by using heuristic optimization method.

  7. Direct Power Control for Three-Phase Two-Level Voltage-Source Rectifiers Based on Extended-State Observation

    DEFF Research Database (Denmark)

    Song, Zhanfeng; Tian, Yanjun; Yan, Zhuo

    2016-01-01

    This paper proposed a direct power control strategy for three-phase two-level voltage-source rectifiers based on extended-state observation. Active and reactive powers are directly regulated in the stationary reference frame. Similar to the family of predictive controllers whose inherent...... characteristic is highly dynamic behaviors, the proposed control strategy can present comparably enhanced transient performance. Furthermore, excellent steady-state power performance can also be observed when the proposed control scheme is adopted. In addition, another attractive feature lies in its robust...... performance, facilitating the successful suppression of performance deterioration caused by parameter variations and model inaccuracy. Detailed frequency-domain analysis is provided to verify its effectiveness. Experimental comparisons are also carried out among the finite control set model direct power...

  8. Manpower development for each level of nuclear power plant personnel, experience and problems

    International Nuclear Information System (INIS)

    Martin, H.D.

    1986-01-01

    The following topics to be covered in this report are: Power plant organization and staff categories; basic education and training; practical experience requirements; effects of promotion and fluctuation; social problems associated with training abroad; technical problems and solutions. (orig.)

  9. Wearable Sensor System Powered by a Biofuel Cell for Detection of Lactate Levels in Sweat (Postprint)

    Science.gov (United States)

    2016-05-04

    attractive for development of sensing technology for the monitoring of human performance. Amperometric biosensors are known to be inexpensive, repro...biofuel cells for self-powered biosensors was first discussed in 2001 and has gained momentum in recent years.32–34 Information technology has...lactate biosensor ,35,36 a glucose oxidase BFC power source, an energy har- vester and a micropotentiostat. The following sections describe the development

  10. The Textile Form of Sound

    DEFF Research Database (Denmark)

    Bendixen, Cecilie

    three-dimensional geometries of interfering spheres are created. Textiles are generally a very good sound dampening material. To dampen the sound most effective it should be placed where the sound energy is highest. To find these invisible spots of energy and to reveal the geometry of them, two......Sound is a part of architecture, and sound is complex. Upon this, sound is invisible. How is it then possible to design visual objects that interact with the sound? This paper addresses the problem of how to get access to the complexity of sound and how to make textile material revealing the form...... of sound. This issue is a part of a Ph.D. study at The Danish Design School in Copenhagen. Sound diffusion in architecture is a complex phenomenon. From the sound source the sound spreads in all directions as a sphere of wave fronts. When the sound is reflected from room boundaries or furniture, complex...

  11. DESIGN OF THE THREE-LEVEL MULTICRITERIAL STRATEGY OF HYBRID MARINE POWER PLANT CONTROL FOR A COMBINED PROPULSION COMPLEX

    Directory of Open Access Journals (Sweden)

    V.V. Budashko

    2017-04-01

    Full Text Available Purpose. Efficiency of hybrid ships power plants (SPP combined propulsion complexes (CPC by various criteria for energy management systems strategies. Methodology. Based on the classification system topologies SPP CPC for mechanical, electrical and hybrid types of motors schematic diagrams of management strategies for the criterion of minimum power consumption are defined. Changing the technical component of the traditional approach to building hybrid ships electric power systems (SEPS SPP CPC the principle of modifying the structure of SEPS is applied with the integration of additional static alternative power source as dynamic reserve, which allowed to meet modern requirements for energy efficiency, levels of vibration, noise and degradation effects produced to SPP CPC, in all areas of the energy for the transfer of power from energy to propellers. Modeling of power transmission of energy to propellers in MatLab/Simulink is conducted, using blocks of optimization library and definition of identity markers. Results. Major advantages and disadvantages SPP CPC depending on the topology of energy distribution systems are determined. According to the chosen structure system electricity characteristics were obtained in the process of power transmission SPP CPC and power systems and their control strategies in terms of increased efficiency and eliminate these drawbacks. And finally, mathematical apparatus for research in terms of the development of methods for designing and managing SPP hybrid CPC to reduced fuel consumption, emissions into the environment and improving maintainability, flexibility and comfort level are improved. Originality. The methodology for improving SPP CPC implementation by developing methods of identification markers mutually influencing processes in SPP CPC and the development of implementing these methods of settlement and information systems. Practical value. The method enables iterative optimization parameters SPP CPC, it

  12. System-level considerations for the front-end readout ASIC in the CBM experiment from the power supply perspective

    Science.gov (United States)

    Kasinski, K.; Koczon, P.; Ayet, S.; Löchner, S.; Schmidt, C. J.

    2017-03-01

    New fixed target experiments using high intensity beams with energy up to 10 AGeV from the SIS100 synchrotron presently being constructed at FAIR/GSI are under preparation. Most of the readout electronics and power supplies are expected to be exposed to a very high flux of nuclear reaction products and have to be radiation tolerant up to 3 MRad (TID) and sustain up to 1014/cm2 of 1 MeV neutron equivalent in their life time. Moreover, the mostly minimum ionising particles under investigation leave very little signal in the sensors. Therefore very low noise level amplitude measurements are required by the front-end electronics for effective tracking. Sensor and interconnecting micro-cable capacitance and series resistance in conjunction with intrinsic noise of the charge sensitive amplifier are dominant noise sources in the system. However, the single-ended architecture of the amplifiers employed for the charge processing channels implies a potential problem with noise contributions from power supply sources. Strict system-level constraints leave very little freedom in selecting a power supply structure optimal with respect to: power efficiency, cooling capabilities and power density on modules, but also noise injection to the front-end via the power supply lines. Design of the power supply and distribution system of the Silicon Tracking System in the CBM experiment together with details on the front-end ASICs (STS -XYTER2) and measurement results of power supply and conditioning electronics (selected DC/DC converter and LDO regulators) are presented.

  13. Bioacoustic Spectral Whistle Sound And Behaviour Of Male Dolphin Bottle Nose ( Tursiops aduncus) At Safari Park Indonesia, Cisarua Bogor

    OpenAIRE

    Muhamad Zainuddin Lubis; Sri Pujiyati; Totok Hestirianoto

    2016-01-01

    Whistle sound is generally used for echolocation purposes, while the sound of the blast-beat and whistles play a major role in internal and inter-group communication.The purpose of this research is to know the power spectral patterns and fluctuations in sound based on frequency and Power Spectral Density (PSD) of the sounds produced by dolphins and observing the position of dolphins , Noisy Time Domain (NTD) and behavior using underwater camera, and also comparing between time and sound spect...

  14. CHARACTERISTICS OF TRACHEAL SOUNDS PRECEDING, DURING AND FOLLOWING HYPOPNEA IN PATIENTS WITH OBSTRUCTIVE SLEEP APNEA--HYPOPNEA SYNDROME

    OpenAIRE

    大西, 徳信

    2000-01-01

    The author analyzed night tracheal sounds of hypopnea events in 12 patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). Tracheal sounds were recorded on a video tape recorder through a microphone attached to the anterior neck over the trachea during overnight polysomnography. In each patient ten hypopnea episodes were selected for analysis. Tracheal sounds were analyzed using sound-spectrogram and power spectra. Mean power spectra of inspiratory and expiratory tracheal sounds with...

  15. Fungal levels in houses in the Fukushima Daiichi Nuclear Power Plant evacuation zone after the Great East Japan Earthquake.

    Science.gov (United States)

    Shinohara, Naohide; Tokumura, Masahiro; Hashimoto, Kazuhiro; Asano, Katsuyoshi; Kawakami, Yuji

    2017-10-01

    Residences located within 20 km of the damaged Fukushima Daiichi Nuclear Power Plant were evacuated shortly after the Great East Japan Earthquake. The levels of airborne and surface fungi were measured in six houses in the evacuation zone in August 2012 and February 2013. Airborne fungal levels in all of the houses in the summer were higher than the environmental standard levels for residential houses published in Architectural Institute of Japan (>1000 colony-forming units [CFU]/m 3 ). In two houses whose residents rarely returned to visit, fungal levels were extremely high (>52,000 CFU/m 3 ). Although fungal levels in the winter were much lower than those in the summer, they were still higher than environmental standard levels in several houses. Indoor fungal levels were significantly inversely related to the frequency with which residents returned, but they were not correlated with the air exchange rates, temperature, humidity, or radiation levels. Cladosporium spp. and Penicillium spp. were detected in every house. Aspergillus section Circumdati (Aspergillus ochraceus group) was also detected in several houses. These fungi produced ochratoxin A and ochratoxin B, which have nephrotoxic and carcinogenic potential. The present study suggests that further monitoring of fungal levels is necessary in houses in the Fukushima Daiichi Nuclear Power Plant evacuation zone, and that some houses may require fungal disinfection. The results suggest that residents' health could be at risk owing to the high levels of airborne fungi and toxic fungi Aspergillus section Circumdati. Therefore, monitoring and decontamination/disinfection of fungi are strongly recommended before residents are allowed to return permanently to their homes. In addition, returning to home with a certain frequency and adequate ventilation are necessary during similar situations, e.g., when residents cannot stay in their homes for a long period, because fungal levels in houses in the Fukushima Daiichi

  16. The sounds of nanotechnology

    Science.gov (United States)

    Campbell, Norah; Deane, Cormac; Murphy, Padraig

    2017-07-01

    Public perceptions of nanotechnology are shaped by sound in surprising ways. Our analysis of the audiovisual techniques employed by nanotechnology stakeholders shows that well-chosen sounds can help to win public trust, create value and convey the weird reality of objects on the nanoscale.

  17. Poetry Pages. Sound Effects.

    Science.gov (United States)

    Fina, Allan de

    1992-01-01

    Explains how elementary teachers can help students understand onomatopoeia, suggesting that they define onomatopoeia, share examples of it, read poems and have students discuss onomatopoeic words, act out common household sounds, write about sound effects, and create choral readings of onomatopoeic poems. Two appropriate poems are included. (SM)

  18. Sound propagation in cities

    NARCIS (Netherlands)

    Salomons, E.; Polinder, H.; Lohman, W.; Zhou, H.; Borst, H.

    2009-01-01

    A new engineering model for sound propagation in cities is presented. The model is based on numerical and experimental studies of sound propagation between street canyons. Multiple reflections in the source canyon and the receiver canyon are taken into account in an efficient way, while weak

  19. OMNIDIRECTIONAL SOUND SOURCE

    DEFF Research Database (Denmark)

    1996-01-01

    A sound source comprising a loudspeaker (6) and a hollow coupler (4) with an open inlet which communicates with and is closed by the loudspeaker (6) and an open outlet, said coupler (4) comprising rigid walls which cannot respond to the sound pressures produced by the loudspeaker (6). According...

  20. Breaking the Sound Barrier

    Science.gov (United States)

    Brown, Tom; Boehringer, Kim

    2007-01-01

    Students in a fourth-grade class participated in a series of dynamic sound learning centers followed by a dramatic capstone event--an exploration of the amazing Trashcan Whoosh Waves. It's a notoriously difficult subject to teach, but this hands-on, exploratory approach ignited student interest in sound, promoted language acquisition, and built…