• Title/Summary/Keyword: Loudness

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The Subjective Assessment of the Passenger Vehicle's Muffler Noise (자동차 배기 소음의 주관적 평가 기법 연구)

  • 유승국;김관주
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1995.04a
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    • pp.94-99
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    • 1995
  • In order to improve the sound quality and reduce the noise of engines and vehicles efficiently, it is important to quantify the subjective noise characteristics objectively. The exhaust noises of the passenger vehicles have been measured for the subjective assessments. This paper outlines the objective data by which engine noise can be assessed and the salient features of subjective assessments before proposing an approach by which targets for internal vehicle noise may be set. The method to objectify the subjective assessments has been proposed considering three components - Loudness, Harmonic content, Impulsiveness - which have influence on the subjective assessments.

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The Evaluating Factors on Comfort in a Classroom (교실 실내환경의 쾌적성 평가요소에 대한 기초 연구)

  • 이지숙;윤정숙
    • Journal of the Korean housing association
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    • v.9 no.2
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    • pp.105-109
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    • 1998
  • The purpose of this study was to evaluate comfort in a classroom. The questionnaire was given to 120 university students in the classroom. On the basis of previous studies, the evaluating factors on comfort in a classroom were selected and they were lightness, glareness, air freshness, dust, odor, loudness, distracting sounds, humidity and temperature. The scale of them was used five voting scales. The results showed that the lightness was the most important one among the evaluating factors because a classroom is an environment to have to see many things.

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A Study on the Change of a Formative Expression in the Restorative Fashion (복고풍 패션의 조형적 표현기법 변화에 관한 연구)

  • Lee, Eun-Sook;Chang, Geung-Hae
    • Journal of the Korea Fashion and Costume Design Association
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    • v.12 no.2
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    • pp.55-65
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    • 2010
  • The present study purposed to compare formative expression between the fashion of the end of 19th century - early 20th century and that of the 21st century which were influenced by art nouveau and art deco. For this purpose, we analyzed contents in literature, Internet, etc.,. According to the results of this study, the formative expression of art nouveau were divided into continuous movement, optical illusion and decorative expression. Continuous movement was used to express fancy and soft images in the end of 19th century, and to express images giving the feeling of speed and tension in the 21st century. Optical illusion was expressed by the movement the thin and soft materials with the body movement and the movement of excessive frills adornment. And in movement produced using thin and soft materials and by the bias cutting method in the 21st century. Decorative expression was expressed as fantasy and decadent image in the end of 19th century and as mild passionate and modern image with color combination in the 21st century. The formative expression of art deco were divided into visual simplicity, contrastive loudness, and functional expression. Visual simplicity was expressed as a boyish image in the early of 20th century, but as a complex expression combining simplicity and femininity in the 21st century. Contrastive loudness was expressed by using colors both in the early of 20th century and 21st century. Functional expression was reinforced through the lightening of design and materials in the early of 20th century, but through using bias cutting high tech materials in the 21st century.

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The Psychological Effect of Visual and Auditory Stimuli on the Road Traffic Noise (시청각 정보에 의한 도로교통소음의 심리적 저감효과)

  • Jang, Gil-Soo;Baek, Gun-Jong;Song, Min-Jeong;Shin, Hoon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.11a
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    • pp.1177-1182
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    • 2007
  • This study aims at identifying the effect of preferred visual and auditory stimuli on the road traffic noise perception through the series of psychoacoustic experiments. The first experiment was designed to find the addition effect of a sound reproducing system in a square where lay adjacent to roads with road traffic noise, provide appropriate music corresponding to the varying conditions of weather in the given space. In result, it was found that the rating around the square improved toward more positive adjectives. The second experiment was designed to assess the visual effect of twelve roadsides with different landscapes on the road traffic noise perception. As a result, approx. 3 to 5 dB(A) of psychological reduction was seen in places where natural landscape was preferred, compared to the others, although the noise levels were similar. The third experiment was designed to evaluate the effect of visual screen from adjacent roads on road traffic noise perception by means of ME method in a laboratory. In result, the effect of psychological reduction was observed at 65dB(A) or lower. Especially, complete screening from adjacent roads led to 5 to 10% of loudness reduction effect, compared to non-screening cases. Finally, the fourth experiment was designed to evaluate the effect of visual and auditory information with ME method and 7-point SD rating scale in a laboratory. In result, up to 10% of loudness reduction and about 2dB(A) of noise perceptional reduction were seen at 65dB(A) or lower.

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Tonality Design for Sound Quality Evaluation in Printer (프린터 음질평가를 위한 순음도 설계)

  • Kim, Eui-Youl;Lee, Young-Jun;Lee, Sang-Kwon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.22 no.4
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    • pp.318-327
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    • 2012
  • The operating sound radiated from a laser printer includes tonal noise components caused by the rotating mechanical parts such as gear, shaft, motor, fan, etc. The negative effects of the tonal noise components need to be considered in the process of developing a sound quality index for the quantitative evaluation of the emotional satisfaction in terms of psycho-acoustics. However, in a previous paper, it was confirmed that the Aures tonality did not have enough correlation with the results of jury evaluation. The sound quality index based on loudness, articulation index, fluctuation strength has a little problem in considering the effects of rotating mechanical parts on the sound quality. In this paper, to solve the tonality evaluation problem, the calculation algorithm of Aures tonality was investigated in detail to find the cause of decreasing the correlation. The new tonality evaluation model was proposed by modifying and optimizing the masking effect, loudness ratio, and shape of weighting curve based on the basic algorithm of Aures tonality, and applied to two kinds of operating sound groups in order to verify the usefulness of proposed model. As a result, it is confirmed that the proposed tonality evaluation model has enough correlation and usefulness for expressing the tonalness in the operating sounds of laser printers. In the following paper, this results will be used to model the sound quality index as the input data by using the classification algorithm.

The Development and Application of Sound Quality Index for the Improving Luxury Sound Quality of Road Vehicle Power Window System (차량 윈도우 리프트 음질 고급감 향상을 위한 음질 지수 제작 및 개선에의 응용)

  • Kim, Seonghyeon;Park, Dong Chul;Jo, Hyeonho;Sung, Weonchan;Kang, Yeon June
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.24 no.2
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    • pp.108-116
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    • 2014
  • With the increasing the importance of emotional quality of vehicle, the sound quality of systems with electric motor components has become increasingly important. Electric motors are used for windows, seats, sun roof, mirrors, steering columns, windshield wiper and climate control blowers, etc. In this paper, a study was conducted to identify sound quality factors that contribute to customer's satisfaction and preference of the window lift system. Jury test for subjective evaluation was carried out and sound quality index was developed. Averaged sound pressure level and sharpness were significant factors when glass moves down. Also, maximum loudness at stop section and averaged loudness were significant factor when glass moves up. Next, noise source identification was carried out using beam forming method during glass transferred section and impulsive noise at stop section. Several improvement methods were applied using the source identification result. And finally, the degree of sound quality improvement was judged using sound quality index.

Development of an Auto ABLB Test Software (자동 ABLB 검사 소프트웨어 개발)

  • Kang, Deok-Hun;Kim, Jin-Dong;Song, Bok-Deuk;Shin, Bum-Joo;Wang, Soo-Geun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.12
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    • pp.5120-5126
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    • 2010
  • ABLB(Alternate Binaural Loudness Balance) test is one of the medical assessments to diagnose detailed lesion of sensory-neural hearing loss based on a recruitment phenomenon. This paper describes an Auto ABLB test software. This software automatically decides test frequency and intensity of first test tone. And it supports an automatic algorithm that analyses the subject's reponses in the current step and then decides intensity of tone provided in next step. Also, this software supports an interface to control and monitor subject's ABLB test. The assessment result is represented by a ladder diagram. The output of this software has been verified using a digital oscilloscope.

Characteristics of Rustling Sound of Laminated Fabric Utilizing Nano-web (나노웹을 이용한 라미네이트소재의 마찰음 특성)

  • Jeong, Tae-Young;Lee, Eu-Gene;Lee, Seung-Sin;Cho, Gil-Soo
    • Fashion & Textile Research Journal
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    • v.15 no.4
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    • pp.620-629
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    • 2013
  • This study examines the rustling sound characteristics of electrospun nanofiber web laminates according to layer structures. This study assesses mechanical properties and frictional sounds (such as SPL); in addition, Zwicker's psychoacoustic parameters (such as Loudness (Z), Sharpness (Z), Roughness (Z), and Fluctuation strength (Z)) were calculated using the Sound Quality Program (ver.3.2, B&K, Denmark). The result determined how to control these characteristics and minimize rustling sounds. A total of 3 specimens' frictional sound (generated at 0.63 m/s) was recorded using a Simulator for Frictional Sound of Fabrics (Korea Patent No. 10-2008-0105524) and SPLs were analyzed with a Fast Fourier Transformation (FFT). The mechanical properties of fabrics were measured with a KES-FB system. The SPL value of the sound spectrum showed 6.84~58.47dB at 0~17,500Hz. The SPL value was 61.2dB for the 2-layer PU nanofiber web laminates layered on densely woven PET(C1) and was the highest at 65.1dB for the 3-layer PU nanofiber web laminates (C3). Based on SPSS 18.0, it was shown that there is a correlation between mechanical properties and psychoacoustic characteristics. Tensile properties (LT), weight (T), and bending properties (2HB) showed a high correlation with psychoacoustic characteristics. Tensile linearity (LT) with Loudness (Z) showed a negative correlation coefficient; however, weight (T) with Sharpness (Z) and Roughness (Z), and bending hysteresis (2HB) with Roughness (Z) indicated positive correlation coefficients, respectively.

A Basic Study on the Conversion of Color Image into Musical Elements based on a Synesthetic Perception (공감각인지기반 컬러이미지-음악요소 변환에 관한 기초연구)

  • Kim, Sung-Il
    • Science of Emotion and Sensibility
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    • v.16 no.2
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    • pp.187-194
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    • 2013
  • The final aim of the present study is to build a system of converting a color image into musical elements based on a synesthetic perception, emulating human synesthetic skills, which make it possible to associate a color image with a specific sound. This can be done on the basis of the similarities between physical frequency information of both light and sound. As a first step, an input true color image is converted into hue, saturation, and intensity domains based on a color model conversion theory. In the next step, musical elements including note, octave, loudness, and duration are extracted from each domain of the HSI color model. A fundamental frequency (F0) is then extracted from both hue and intensity histograms. The loudness and duration are extracted from both intensity and saturation histograms, respectively. In experiments, the proposed system on the conversion of a color image into musical elements was implemented using standard C and Microsoft Visual C++(ver. 6.0). Through the proposed system, the extracted musical elements were synthesized to finally generate a sound source in a WAV file format. The simulation results revealed that the musical elements, which were extracted from an input RGB color image, reflected in its output sound signals.

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Treatment of Snoring and Obstructive Sleep Apnea with Dental Orthosis (구강내 장치를 이용한 코골이 및 폐쇄성 수면무호흡증의 치료효과)

  • 안홍균
    • Journal of Oral Medicine and Pain
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    • v.22 no.2
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    • pp.383-394
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    • 1997
  • The purpose of this study was to examine the anatomic changes in the upper airway with a dental orthosis. the effectiveness and side effects of orthosis in the treatment of snoring and obstructive sleep apnea. To meet this puppose a dental orthosis, designed to increase the size of the upper airway by advancing the mandible, was used in 42 patients (30 M, 12 F), aged 29 - 69 years, to treat snoring and varying decrees of obstructive sleep apnea. Cephalometric study of anatomic featured was made with and without a dental orthosis, and the evaluation of the effectiveness and side effects of orthosis was done by questionnaires. The obtained results were as follows : 1. All subjects were habitual snorers and 32 patients comp1ained the loudness of snoring as severe as be heard outside of the patient's room. 2. According to the degree of respiratory distirbance index(RDI) and aprea index(Al) from the polysomnograph in 34 patient, mild obstructive sleep apnea patients were 5, moderate 6 and severe 16. 3. Various anatomic changes in the upper airway with denta1 orthosis were as follows : (1) More superioly positioned hyoid bone ( p<0.001) (2) Enlarged oropharyngeal (superior p<0.01, middle p<0.01. inferior p<0.01) and hypopharyngeal (P<0.05) airway space. 4. According to the results of the changes of clinical syptoms after the usage of the dental orthosis acquired from questionnaires, there was significant improvement in the frequently, the loudness and the severity of snoring, cessation of breathing and awakening from the difficulty of breathing during sleep. 5. The effectiveness and side effects of dental orthosis by questionnaires were as follows ; (1) Dental orthosis satisfied almost all the patients (68±20%). (2) Snoring was improved in all the patients (73±19%). (3) Obstructive sleep aphea was improved in all the patients (61 ± 37%) (4) Sleepiness in the daytime was significantly improved (61 ±37%). (5) The sleep quality was significantly improved (61±37%). (6) The discomfort of the dental orthosis was minor (33±18%) and no serious complications were observed. 6. The dental orthosis is an effective treatment for the symptom of snoring, and it can also effectively treat varying degrees of obstructive sleep apnea.

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