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Adaptive Noise Reduction for Sound Event Detection Using Subband-Weighted NMF

Adaptive Noise Reduction for Sound Event Detection Using Subband-Weighted NMF

Received: 26 May 2019; Accepted: 17 July 2019; Published: 20 July 2019 Abstract: Sound event detection in real-world environments suffers from the interference of non-stationary and time-varying noise. This paper presents an adaptive noise reduction method for sound event detection based on non-negative matrix factorization (NMF). First, a scheme for noise dictionary learning from the input noisy signal is employed by the technique of robust NMF, which supports adaptation to noise variations. The estimated noise dictionary is used to develop a supervised source separation framework in combination with a pre-trained event dictionary. Second, to improve the separation quality, we extend the basic NMF model to a weighted form, with the aim of varying the relative importance of the different components when separating a target sound event from noise. With properly designed weights, the separation process is forced to rely more on those dominant event components, whereas the noise gets greatly suppressed. The proposed method is evaluated on a dataset of the rare sound event detection task of the DCASE 2017 challenge, and achieves comparable results to the top-ranking system based on convolutional recurrent neural networks (CRNNs). The proposed weighted NMF method shows an excellent noise reduction ability, and achieves an improvement of an F-score by 5%, compared to the unweighted approach.

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Airborne sound insulation in terms of a loudness model

Airborne sound insulation in terms of a loudness model

The investigations thus far indicate that the airborne sound insulation measured in accordance with present standards [21] does not correlate well with subjective impression [22, 23, 24, 25, 26, 27]. These results reveal that, in line with previous reports, the level difference measured tends to produce lower correlations than the corresponding transmission loss measures, and this contradicts suggestions that differences in sound level would correlate best with subjective responses [28]. In the meantime, it has been reported that loudness combined with roughness describes the correlation with subjective estimation of noise-induced discomfort better than the A-weighted sound level [29]. Moreover, as Jeon et al. [30, 31] noted, subjective response to noises, such as annoyance, depend upon the type of noise.

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Analysis of Noise Emitted from Electrical Machines Using TOPSIS Technique

Analysis of Noise Emitted from Electrical Machines Using TOPSIS Technique

same acoustic energy as a given noise event lasting for a period of time T. LAV (Average sound level) is defined as the total energy averaged over the total time. TWA (Time weighted average) is the noise that is weighted over a certain amount of time such as 8 hours for machine noise. Noise dose readings have been taken for different DC machines such as DC shunt motor, DC generator and AC machines like wound rotor induction motor, squirrel cage induction motor, single phase induction motor and synchronous motor. It is very important to measure noise dose, as well as, different parameters related to noise dose or sound pressure level. The machines which produce noise levels as high as 120 dBA or more violate the rules of National Fire Protection Association guidelines (1993 A.D.) [8]. The legislation describe on OSHA (1992 A.D.) is that, when a human is exposed to 90 dBA for 8 hrs, he has a 100 percent dose. So, 100 percent noise dose is always representing the criterion dose whatever may be the duration of measurement [9]. Noise dose parameters like LAeq, LAE, LAV and TWA are estimated and analyzed by TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) technique for each electrical machine and lastly more noise exposing electrical machines are identified.

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Effects of signal processing on the measurement of maximum sound pressure levels

Effects of signal processing on the measurement of maximum sound pressure levels

Maximum sound pressure levels are commonly used for environmental noise and building acoustics measurements. This paper investigates the signal processing errors due to Fast or Slow time-weighting detectors when combined with octave band filters, one-third octave band filters or an A-weighting filter. For 6th order Butterworth CPB filters the inherent time delay caused by the phase response of filters is quantified using three different approaches to establish the following rules-of-thumb: (1) time-to-gradi- ent/amplitude matching occurs when Bt 1, (2) time-to-peak matching occurs when Bt 2 and (3) time- to-settle matching occurs when Bt 4 for octave band filters, and when Bt 3 for one-third octave band filters. Four different commercially-available sound level meters are used to quantify the variation in measured maximum levels using tone bursts, half-sine pulses, ramped noise and recorded transients. Tone bursts indicate that Slow time-weighting is inappropriate for maximum level measurements due to the large bias error. The results also show that there is more variation between sound level meters when considering Fast time-weighted maximum levels in octave bands or one-third octave bands than with A-weighted levels. To reduce the variation between measurements with different sound level meters, it is proposed that limits could be prescribed on the phase response for CPB filters and A-weight- ing filters.

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Monitoring of the Noise Emitted by Machine Tools in Industrial Conditions

Monitoring of the Noise Emitted by Machine Tools in Industrial Conditions

(LAmax) should not exceed 115 dB; the peak C- weighted sound level (LCpeak) should not ex- ceed 135 dB. The exposure action values are set out in the Regulation of the Minister of Economy and Labour on Occupational Safety and Health for Works Related with Exposure to Noise or Me- chanical Vibrations. These values are as follows: noise exposure level applicable to an 8-hour working day or weekly noise exposure level – 80 dB; the peak C-weighted sound level – 135 dB. The above-mentioned normative values apply if other provisions do not specify the lower expo- sure action values (e.g. in the workstations occu- pied by young people – LEX,8 h = 80 dB, and in the workstations occupied by pregnant women – LEX,8 h = 65 dB). However, as it turns out, the noise emission in industrial plants is slightly decreasing, compared to the previous research periods. Increasingly, the stringent rules for the protection of health require to reduce the airborne noise emissions from industrial plants. This is fa- cilitated by a change of mentality and approach to the protection of workers’ health as well as the introduction of new “low-noise” and more “en- vironmentally friendly” means of production, i.e machine tools.

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Systematic Tool Support of Engineering Education Performance Management

Systematic Tool Support of Engineering Education Performance Management

Engineering schools must adopt or develop their own systems and processes for graduate attribute assessment. In this paper, we take a systems engineering approach to graduate attribute assessment and propose a system architecture and tool-supported continuous improvement process with key algorithms and mathematical analysis to process the data and provide performance management reporting. Over several iterations, we have introduced and evaluated improved systems support in a collection of tools called the Graduate Attribute Information Analysis system (GAIA). GAIA integrates course indicators as well as external indicators from a variety of sources. It provides a tool-supported continuous improvement process with templates and notifications for all deliverables. There are sound algorithms and tool support and built-in mathematical analysis for data collection and reporting that includes quantitative and qualitative data; weighted grading; historic trend analysis; improved visualization of results; and standardized reports at both the course level and the program level that can be used either for accreditation or to inform program improvement.

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Monitoring Gas Metal Arc Welding Process by Using Audible Sound Signal

Monitoring Gas Metal Arc Welding Process by Using Audible Sound Signal

The gas metal arc welding (GMAW) process is widely used because it is highly productive and cost effective. The process is suitable for robotization and mechanization. To maintain and direct the welding arc, an experienced welder uses their senses, especially eyes and ears to combine visual and audible information [1]. Unfortunately, during the GMAW process there are more high intensity side effects, such as heat, light and noise. At the same welding parameters audible A-weighted sound pressure level can rise above the daily permissible level of the welder’s ear, 80 dB. Measurements have shown that equivalent A-weighted sound pressure level can even exceed 100 dB at the welder ear. On the other hand, the noise can be used for monitoring the quality of the welding process as well as for checking for anomalies in the welding process. The significance of sound in monitoring the arc welding processes has been known for a long time, but relatively few studies have been published in which sound waves are regarded as a source of information for monitoring the welding process.

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Frequency analysis of noise exposure of dairy cows in the process of milking

Frequency analysis of noise exposure of dairy cows in the process of milking

Data acquisition. Noise measurements were car- ried out at three places: (1) in the area of milking, (2) in the stable and (3) in the space where cows waited for milking. Measurements were made at these places during the milking process, both when the milking equipment was on and also when the milking equipment was off. The measuring device was placed at the level of animal heads. Equivalent sound pressure level (LZFekv) was recorded. This level reflects the value of equivalent sound energy measured for a given period, with a zero-weighted filter. Another measured parameter was the max. time-weighted level (LZFmax) with zero-weighted weighting filter. Each measurement lasted 1  min, and each measurement point was measured 10 times when the milking equipment was on and 10 times when the milking equipment was off.

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Effect of No-load and Load Condition on Transformer Sound Dr. Hitesh Paghadar

Effect of No-load and Load Condition on Transformer Sound Dr. Hitesh Paghadar

Increasing environment noise pollution is a matter of great concern and of late has been attracting public attention. Sound produces the minute oscillatory changes in air pressure and is audible to the human ear when in the frequency range of 20Hz to 20 kHz. The chief sources of audible sound are the magnetic circuit of transformer which produces sound due to magnetostriction phenomenon, vibration of windings, tank and other structural parts, and the noise produced by cooling equipments. This paper presents the validation for sound level measurement scale, why A-weighted scale is accepted for sound level measurement, experimental study carried out on 10MVA Power Transformer. Also presents the outcomes of comparison between No-Load sound & Load sound level measurement, experimental study carried out on different transformer like - 10MVA, 50MVA, 100MVA Power Transformer, to define the dominant factor of transformer sound generation.

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An energy interpretation of the Kirchhoff Helmholtz boundary integral equation and its application to Sound Field synthesis

An energy interpretation of the Kirchhoff Helmholtz boundary integral equation and its application to Sound Field synthesis

reproducing a sound field in an enclosed volume. Probably the most widely cited use of the KHBIE in spatial audio is in its directly implemented manifestation as Wave Field Synthesis. Here it usually appears in its dipole-free Single-Layer Potential (SLP) form, due to practical difficulties of realizing broadband dipole loudspeakers. This surface of monopoles is still capable of realizing the same sound field within the enclosed volume as the full KHBIE; however it will also radiate additional sound energy back into the exterior of the array. This has implications for spatial audio systems located in real rooms. It also means that finding the monopole density for an arbitrary shaped array involves solving an inverse problem; this would not be necessary if both monopoles and dipoles were to be used together, since inspection of the KHBIE gives the driving functions directly.

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How Cinema Sounds Affect the Perception of a Motion Picture

How Cinema Sounds Affect the Perception of a Motion Picture

Abstract The object of the present study was to investigate the effects of sound on the perception of motion pictures by film viewers. For this purpose, we selected a sequence from the film “Elephant” (G. Van Sant, 2003) and composed two alternative soundtracks. The three different versions of the sequence (one with the original soundtrack and two with the alternative ones) were screened to 51 adult students (mean age 21.3 y.o.), who answered a series of questions after each screening. We concluded that different soundtracks change the perception of the audience mainly concerning the recognition of the film gender and the emotions that the viewers develop while watching the sequence. Moreover, the sound-design can possibly create visual illusions when the source of sound is shown on screen. Finally, factors like the sex and the field of studies seemed to differentiate our results, thus revealing their potential effect on the viewer’s perception.

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Sensory habituation of auditory receptor neurons: implications for sound localization

Sensory habituation of auditory receptor neurons: implications for sound localization

Sound localization in the horizontal plane is based on binaural comparison of sound features. Sound sources that are displaced from the midline generate interaural differences in timing and intensity. Microsecond-level differences in timing result from direction-dependent differences in path length from the source to each ear, and some vertebrates can use this as a localization cue (Carr, 1993). Intensity differences arise as a result of reflection and diffraction of sound by the portion of the body between the ears and/or because of interference between sounds arriving at each ear along multiple paths (Michelsen et al., 1994; Miles et al., 1995). These physical cues for sound direction are reported to the central nervous system by auditory receptor neurons. Stimulus onset and phase are represented by spike timing, whereas stimulus intensity affects both the timing (latency) and the strength (spike rate and/or count) of responses.

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A Novel Symbolic Algorithm for Maximum Weighted Matching in Bipartite Graphs

A Novel Symbolic Algorithm for Maximum Weighted Matching in Bipartite Graphs

The matching problems find their applications in many settings where we often wish to find the proper way to pair objects or people together to achieve some desired goal. The matching problems are classified into maxi- mum cardinality matching in bipartite graphs, maximum cardinality matching in general graphs, maximum weighted matching in bipartite graphs, and maximum weighted matching in general graphs [1,2]. The first is looking for a matching with the maximum edges, in which nodes are partitioned into boys and girls, and an edge can only join a boy and a girl; The second is the asexual case, where an edge joins two persons; In the third, we still have nodes representing boys and girls, but each edge has a weight associated with it. Our goal is to find a matching

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The Third Section: reveals the main findings of the study that relate to the inflection of nouns, verbs and

The Third Section: reveals the main findings of the study that relate to the inflection of nouns, verbs and

Nouns that generally do not take the inflectional possessive {-‗s} are inanimate nouns, although there are certain inanimate nouns that do take the inflection possessive {-‗s}. These are generally collective nouns that refer to group of people such as company, team, committee or government. Most inanimate nouns take ―off phrase‖ to show possession, as in the back of desk not * the desk‘s back.Consequently, while ESL/EFL learners may want to know exactly when they can or cannot use the inflectional possessive {-‗s}, there is no hard and fast rule for them to follow, just general guide lines. When ESL/EFL learners do use the inflectional possessive {-‗s} where native speakers would not, such errors are not serious. They generally do not cause misunderstandings and rarely stigmatized by native speakers. (Andrea DeCapua; 2008:66)

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Innovation in the Energy Industry: Evidence from Patent Indicators.

Innovation in the Energy Industry: Evidence from Patent Indicators.

In the first chapter, I explore the effects of biofuels policies such as ethanol blend mandates on patenting in patent categories related to biofuels. In addition, I investigate the impacts of these policies on agricultural biotechnology. Using a Bayesisan model averaging approach, I find that ethanol blend mandates, the most common form of policy designed to stimulate the use of biofuels, have a significant positive effect on biofuels patent counts and a significant negative effect on certain agricultural biotechnology patent counts. When looking at quality-weighted patenting, a measurement of innovative output, I find that there is a significant increase in the weighted patents for biofuels but no significant decrease in output for agricultural biotechnology in response to the blend mandates. Together, these findings suggest that while the blend mandates redirect effort from agricultural biotechnology to biofuels-specific categories, this does not reduce overall output. This could be evidence that scientific insights generated through researching biofuels are beneficial to performing agricultural biotechnology research, as the same level of innovative output is generated with reduced levels of innovative inputs.

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A false killer whale reduces its hearing sensitivity when a loud sound is preceded by a warning

A false killer whale reduces its hearing sensitivity when a loud sound is preceded by a warning

The study was carried out at the facilities of the Hawaii Institute of Marine Biology, Marine Mammal Research Program. The subject was an originally wild-caught female false killer whale, Pseudorca crassidens (Owen 1846), assumed to be between 30 and 40years old. The subject was trained to accept suction-cup electrodes for brain-potential recording, to swim into a hoop station and to listen to the sound stimuli. She had hearing loss for frequencies above 35kHz; however, her hearing sensitivity within a range of up to 25kHz (Yuen et al., 2005) was nearly normal compared with the majority of other odontocetes (Supin et al., 2001). The subject was housed in a floating pen complex. Experiments were carried out in a section of the pen complex that was 8×10m in size.

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Effect of Seabed Topography Change on Sound Ray Propagation—A Simulation Study

Effect of Seabed Topography Change on Sound Ray Propagation—A Simulation Study

When propagating in seawater, sound ray may be af- fected by environmental factors such as sea surface and submarine boundary. The study of sound ray propagation in seawater is mainly ray theory. Sound wave propaga- tion in seawater is looked up as sound ray propagation in medium in the context of high frequency. The change of sound intensity, the time and distance of sound ray pro- pagation in space are mainly studied. Ray acoustics is an approximate method, which is only for the sound wave of high frequency. But in many cases, this method is ef- fective and effective to solve the problem in seawater [1]. Modeling and Simulating of sound wave propagation is important to sonar’s using and optimum designing in water. There are already some simulating study reports on sea sound propagation effect and characteristic of sound channel under perfect environment [2,3].

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Innovative Noise Analysis and Abatement Design for Large Mining Vehicles

Innovative Noise Analysis and Abatement Design for Large Mining Vehicles

Once the data was acquired using B&K Pulse Labshop, it was imported into the Array Acoustic Post-Processing application for the processing of the NSI results. For this, the refined beamforming algorithm was used to process the results. The refined beamforming approach uses the non-negative least square (NNLS) algorithm, which is a derivation of the deconvolution beamforming method and was chosen as it can give the highest spatial resolution. For both the pass-by and the stationary measurements, sound intensity levels were calculated over the frequency range of 50 Hz to 5 kHz in 1/3-octave frequency bands. The benefit of getting a sound intensity level map is that the sound power level can be easily calculated by performing a simple integration over a chosen region on the sound intensity map. This eases the quantification of the impact of sub-sources and regions on the overall noise emissions for the mining haul truck. Using overall and 1/3- octave sound power levels, the contribution of each sub-source to the overall noise contribution and the frequency band contributions were ranked. These comparisons can give valuable insight on where to target applications of noise control.

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A novel five-category multimodal T1-weighted and T2-weighted magnetic resonance imaging-based stratification system for the selection of spinal arachnoid cyst treatment: a 15-year experience of 81 cases

A novel five-category multimodal T1-weighted and T2-weighted magnetic resonance imaging-based stratification system for the selection of spinal arachnoid cyst treatment: a 15-year experience of 81 cases

Patients and methods: A retrospective study was conducted in 81 spinal arachnoid cyst patients (male:female 34:47, mean age 36.5 years, age range 6–66 years) classified using a novel five-category T1-weighted and T2-weighted magnetic resonance imaging (MRI) classification system (intramedullary, subdural extramedullary, subdural/epidural, intraspinal epidural, or intraspinal/extraspinal). Conservative treatment failed in all patients. They underwent spinal surgery between January 1995 and December 2010 and were followed up for 69 (range 3–187) months. Performance outcomes were assessed using the Fugl-Meyer (FM) scale 90 days after operation. Recurrences and deaths were recorded.

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A Metanalysis on the Role of Audio Visual Cartoons in Language Acquisiton Among Primary School Children

A Metanalysis on the Role of Audio Visual Cartoons in Language Acquisiton Among Primary School Children

ABSTRACT: In literature, there are claims that language is a sole reason for shaping the identity of an individual. To learn a global language, without undermining the native language of a person is a difficult task. Language learners of different corners of the world, struggle to learn a foreign language. Education is based on a curriculum provided in a static, formal and systematic manner, which may not equally benefit the introvert and extrovert students in the context of language learning. Cartoons are the most delightful illustrations that can help primary school children in learning the foreign languages as well creating a firm foundation of their native language, with the visuals and audios of clarity in cartoons. When a language is studied in linguistic institutions, there is a challenging task of acquiring a native like pronunciation of the language. If a native speaker of the language is the teacher, it will be difficult for the students to acquire the exact pronunciation and it will be hard to comprehend what is taught. Often non native speakers of a language teach students the foreign languages, which can result in miscommunication of pronunciation and various aspects related to the language.Children at a very early age have the capacity of bilingualism, and cartoons can help them to acquire the exact pronunciation of the foreign languages as cartoons are available in different languages and are educative in today’s world. This paper is intended to contribute to education with an easy method for producing an intelligible pronunciation of a language through cartoons for primary school children and adults can also be benefitted as cartoons can grip the attention of a language learner regardless of their age using the method of sample survey.

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