• The Journal of the Acoustical Society of Korea
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• v.22 no.2
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• pp.113-120
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• 2003

Rayleigh was an excellent experimenter as well as a theorist. Rayleigh improved Rijke's sounding device by heat and the singing flame into sources of pure tones. Above all, his making of the artificial bird whistle was a critical achievement in the improvement of experimental sound sources. This source made supersonic waves available in the laboratory and thus paved the way to confirmable observations of reflection, refraction, diffraction and interference of sound in the laboratory Furthermore, Rayleigh augmented the sensitivity of sensitive flames as detectors for sound wave. Besides, he devised a phonic wheel which could precisely control the angular velocity of some acoustical instruments and made the Rayleigh-disk that enabled experimenters to measure the absolute value of the sound intensity. These devices enhanced the exactness of acoustical experiments.

• Korean Journal of Child Studies
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• v.36 no.6
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• pp.101-123
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• 2015

The purpose of this study was to examine how musical pieces were presented in music activities on the Teacher's Guidebooks in order for young children to experience the aesthetics of music. For the purposes of this research, the ways to address musical elements and the music activities of 100 musical works in the Teacher's Guidebooks were analyzed. In addition, the aesthetic qualities of the same musical pieces presented by the sound sources were examined. Following this, an analysis of the relationship between the elements used and the aesthetic qualities of the music was carried out by comparing the previous analysis. The results were as follows. First, melody (38.1%), rhythm (29.0%), and timbre (20.5%) were the most utilized elements of musical works in such activities. Secondly, the most utilized method to present music activities was singing. Among 100 musical pieces, 74 pieces used singing activities. Next, the most audible aesthetic quality from sound sources was that of the melody, presented in 69 pieces (46.6%) among 100 musical works. Lastly, among 100 musical works, at least 64 pieces were matched with more than one, whereas 34 did not.

• Speech Sciences
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• v.10 no.2
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• pp.169-189
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• 2003

Trained singers, one group of professional voice users, have much more interest on the voice than common people, and on its management, too. They train for singing beautiful songs, and, at the same time, try for efficient voice production. The present study was performed with three tenors and three baritones, undergraduate students majored in classical singing, to investigate the degree of improvement of their voice production efficiency through vocal function exercise, by measuring the three dependent variables, maximum phonation time, speed quotient of glottal contact, and the number of semi tones. For the baseline establishment, dependent variables were measured 3$\sim$6 times for two weeks. Then, the subjects exercised vocal function exercise for seven weeks, and after the termination of training, evaluation was performed four times for two weeks, to find the maintenance of the training effect. Vocal function exercise is composed of four successive steps: warm-up, stretching exercise, contracting exercise, power exercise. As results, all of six subjects showed improvement in the aspect of maximum phonation time, speed quotient if glottal contact, and the number of semitones.

• Human Ecology Research
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• v.56 no.4
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• pp.331-345
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• 2018

This study explored the sandplay therapy case of a woman with a negative mother complex who wants to be free from family life. The goal of the therapy was to make her free from family life by expressing repressed emotions for getting out of a negative mother complex under a free and protected space in sandplay therapy. Twenty-three therapy sessions were held. The client exhibited a singing woman in a gorgeous dress and things she wanted to do in the initial phase of therapy (1-4, forgotten myself). In the intermediate phase of therapy (5-15, differentiation and integration), she displayed the scenes of differentiation and integration by emotionally getting rid of a begging boy and making mandalas. In the final phase of therapy (16-23, recovered myself), she showed scenes of rebirth, upgrading and singing songs again in front of family members and many people. Through sandplay therapy in the free and protected space, this study showed the effectiveness of sandplay therapy since the client achieved individuation by showing rebirth, having a new personality.

• Journal of Korean Academy of Rural Health Nursing
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• v.2 no.1
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• pp.24-32
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• 2007

Purpose: This study was done to provide statistical data for developing client-needs based welfare services in community welfare facilities. Method: The participants were 270 senior citizens, who visited a community welfare center in Gyunggi province, during the month of October 2005. They were asked to answer a structured questionnaire. Descriptive statistics, $X^2$ test and Fisher's exact test were used to analyze the data from 221 of the elders. Results: 1. More than 50% of the respondents were women aged between 60 and 75, who had education levels above high school and who lived in apartments. Among the respondents, 54.3% lived separately from their children. 2. 70.0% of the respondents considered their health status as "good", even though they had more than one disease. Also 41% of the respondents were supported by their children, and 76.8% wanted jobs. 3. The respondents pointed out several programs such as languages, computer, singing class, physical activities (dances, billiards, Tai-chi and table tennis), needed to be included in the welfare center programs. Conclusions: Elders aged 60-75, educated above high school, living in an apartments, live alone or with spouse, and having frequent contact with children, were the most frequent utilizers of the welfare center. They want the welfare center programs in variety, including languages, computer, singing class, and physical activities.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.955-962
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• 2002

According to the trends of construction of large size vessel with high power, the natural frequencies of the bending modes of propeller blades have been lower than the past. Therefore, it is expected that the noise and vibration problems of the marine propeller are frequently occurred. As main issue of the propeller noise and vibration problem, the cavitation noise and singing noise due to the flow induced excitation of the bending modes of propeller blade in the high frequency range has been studied by the hydrodynamic researchers in the view point of the excitation force reduction. In this paper, the vibration mode characteristics of propeller with a large diameter in very large vessel are investigated by the vibration analysis of the finite element method using MSC/Nastran and the vibration measurement by the impact test on the propeller blade. According to the results, the natural frequencies of various blade bending modes in water entrained condition could be estimated from the natural frequencies taken by the measurement and free vibration analysis in the dry condition, and it could be estimated how the high frequency noise such as singing is generated from the blade bending modes.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.3
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• pp.233-237
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• 2011

In the present experiments, vortical structures behind the hydrofoil trailing edge are visualized and analyzed as an elementary study for propeller singing phenomena. Two sorts of hydrofoil are selected for the measurement of shedding vortices. One was KH45 hydrofoil section and the other is KH45 with the truncated trailing edge that is positioned at X/C = 0.9523(C=chord length). Assuming the Strouhal number of 0.23, the shedding frequencies of vortices are extracted by analyzing the boundary layer thickness and the flow speed. The frequency distribution of shedding vortices is obtained with the variation of angle-of-attack while the flow speed is fixed to 8m/s. The truncation of the trailing edge makes the frequency of shedding vortices about 120Hz lower than that of original trailing edge and makes the vorticity value higher than the original trailing edge.

• Phonetics and Speech Sciences
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• v.4 no.2
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• pp.115-120
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• 2012

This study sought to compare breath competence in three different utterance conditions when reading a passage aloud, making a spontaneous speech, and singing. We tested 15 normal females (ages averaging $24{\pm}4.4$) and measured breath competence through an objective, aero-mechanical instrument called PAS (Phonatory aerodynamic system, model 6600, KAY Electronics, Inc). Breathing sets of inspiration and expiration were measured by breath group number, breath group duration, and the ratio of inspiration to expiration. The results from this study led us to the following conclusion: The breath group number and the breath group duration showed no significant difference. However, the only variance that we could find was in the ratio of inspiration and expiration. In significantly different speech patterns, singing resulted in the most varied ratio of inspiration and expiration, followed by reading a text aloud, and spontaneous speech. The average frequency rates and maximum intensity levels varied with regards to varying utterance conditions. This thus shows that breath competence and phonation competence have a closely interrelated relationship.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.97-106
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• 2005

According to the trends of construction of large size vessel with high power the natural frequencies of the bending modes of propeller blades have been lower than the past. Therefore, it is expected that the noise and vibration problems of the marine propeller are frequently occurred. As main issue of the propeller noise and vibration problem, the cavitation noise and singing noise due to the flow induced excitation of the bending modes of propeller blade in the high frequency range has been studied by the hydrodynamic researchers in the view point of the excitation force reduction. In this paper, the vibration mode characteristics of propeller with a large diameter in very large vessel are investigated by the vibration analysis of the finite element method using MSC/Nastran and the vibration measurement by the impact test on the propeller blade. According to the results, the natural frequencies of various blade bending modes in water entrained condition could be estimated from the natural frequencies taken by the measurement and free vibration analysis in the dry condition, and it could be estimated how the high frequency noise such as singing is generated from the blade bending modes.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.1010-1013
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• 2003

It is said that the goal of the design of good acoustical environment is at first the reduction of undesirable sounds, and in addition the introduction of desirable sounds by which our minds are soothed. The task of creating the desirable sounds leads to the realization of a comfortable acoustic environment and the design of soundscape. It may be an important starting point of soundscape design to select suitable sounds for the target spaces, because each space has a different surrounding condition and requires a special ambient sound. This paper aims to survey preference of the environmental sounds suitable for the public spaces in urban areas such as parks, bus terminals. 35 kinds of natural sounds are rated by 26 pairs of adjectives. The results of psycho-acoustic experiments are as follows. 1. The proper adjectives for expressing the environmental sounds are classified into 6 groups of comfort, pleasure, fullness, variety, distinctness, naturalness. 2. Bird singing, murmuring of a stream, artificial sounds, singing of insects and animals are the affirmative order of preference. 3. Green musics consisted of music and natural sounds are preferred to the pure natural sounds. 4. Sound level relative to background noise causes various preferences to natural sounds in public spaces.