• Journal of the Korean Institute of Gas
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• v.13 no.1
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• pp.9-13
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• 2009

A cause of noise and vibration which come from a Combustion of gas heater are a combustion roar and Combustion oscillation. A character of a combustion roar is that sound pressure is distribute with broad band frequency. otherwise, The presence of combustion oscillation caused by positive Feed Back in Combustion Chamber break out a noise and vibration. Accordingly, The method that be solved a noise and vibration is to make each natural frequency different frequency. first, in order to solve problem, we control ratio of fuel and air. that is, Keep away resonance. second, in order to changing natural frequency of Combustion Chamber, We changed the shape of Economizer.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.2
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• pp.195-202
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• 2015

Hundreds of Steller sea lions, Eumetopias jubatus, migrate from Sakhalin and the northern Kuril Islands to Hokkaido in Japan every winter. During this migration, they may use their roaring sounds to navigate and to maintain their groups. We recorded the roars of wild Steller sea lions that had landed on reefs on the west coast of Hokkaido, and those of captive sea lions, while making video recordings. The fundamental frequency ($F_0$), Formant frequency ($F_1$), pulse repetition rate (PRR), and duration of syllables (T) were analyzed using a sonagraph. $F_0$, $F_1$, and PRR of the roars emitted by captive sea lions increased in the order male, female. By contrast, the $F_1$ of wild males was lower than that of females, while the $F_0$ and PRR of wild males and females did not differ statistically. These results suggest regional differences between the five groups showed that.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.4
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• pp.458-465
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• 2010

Hundreds of Steller sea lions, Eumetopias jubatus, migrate from Sakhalin and the northern Kuril Islands to Hokkaido every winter. During this migration, they may use their roaring sounds to navigate and to maintain their groups. We recorded the roars of wild Steller sea lions that had landed on reefs on the west coast of Hokkaido, and those of captive sea lions, while making video recordings. A total of 300 roars of wild sea lions and 870 roars of captive sea lions were sampled. The fundamental frequency ($F_0$), formant frequency ($F_1$), pulse repetition rate (PRR), and duration of syllables (T) were analyzed using a sonagraph. $F_0$, $F_1$, and PRR of the roars emitted by captive sea lions increased in the order male, female, and juvenile. By contrast, the $F_1$ of wild males was lower than that of females, while the $F_0$ and PRR of wild males and females did not differ statistically. Moreover, the $F_0$ and $F_1$ frequencies for captive sea lions were higher than those of wild sea lions, while PRR in captive sea lions was lower than in wild sea lions. Since there was a linear relationship between body length and the $F_0$ and $F_1$ frequencies in captive sea lions, the body length distribution of wild sea lions could be estimated from the $F_0$ and $F_1$ frequency distribution using a regression equation. These results roughly agree with the body length distribution derived from photographic geometry. As the volume of the oral cavity and the length of the vocal cords are generally proportional to body length, sampled roars can provide useful information about a population, such as the body length distribution and sex ratio.

• Korean journal of communication and information
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• v.31
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• pp.85-111
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• 2005

This paper aims at dealing with the communication of Korean gong sound. It is based on 'music-spirit theory' of Han-Gi Choi and Mead's 'symbolic interactionism', and does this by interpreting the message of gong sound that is mentioned in Korean literature. The gong sound brings out the message of symbolizing evaporation of Korean people's joy and regrettable matters in the playing yard by regulating of breathing according to the steps. By the novel "Gong Sound" of Sun-Tae Moon Korean gong sound has a message of people's joy, anger, avarice, anxiety and sorrow. In Jeong-Rae Jo's novel "Arirang" the Korean Gong Sound includes a message of evaporation of people's regret and raises the national spirit during the Japanese Imperialism. By Jeong-Ja Yoo's collection of poems, "The sound of flower breathing carried by gong sound", the Korean gong sound carries a message of a roar of spirit and breathing of the spring flower. In conclusion, the Korean gong sound is a sublime sound of sky which carries the message of symbolizing evaporation of people's joy and regrettable matters through the sound communication in the open space, and awakes us to a method of breathing with sky.

• Management & Information Systems Review
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• v.4
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• pp.161-200
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• 2000

The results of this study on problems and activation plans of venture business are as follows. First, to ensure substantiality of venture business 1) To prepare and support venture investment capital. 2) To make eggective use of founding capital of venture business. 3) To establish the overall supporting system for founding of venture business. 4) To maintain and ensure manpower for venture business. Second. to prepare investment base for venture business 1) To induce the enlargement of venture investment unions. 2) To ensure the sound trust of KOSDAQ. 3) To permantly setup angel capital investment market. 4) To ensure joint system for R&D and knowledge management, and so forth. Third, to promote environment for the founding of venture business 1) To enlarge and roar business incubator (BI) 2) To establish acts of venture complex. 3) To uplift creative tension feeling and entrepreneurship. 4) To maximum the support for adminstration approvals, and so forth. Fourth, to make global strategy for venture business 1) To furnish oversea venture chances for globaligation to venture business. 2) To operate information network. 3) To establish integrating system of oversea support offices. Fifth, to support capital and tax 1) To activate functions of investment organs. 2) To increase the number of venture investment company. 3) To permanently organige angel capitalists. 4) To reduce and exampt the corporation tax, and the like. Above mentioned results of this study have to be practiced, and in future, subdivided studies will be needed.

• The Journal of the Acoustical Society of Korea
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• v.28 no.4
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• pp.343-355
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• 2009

In order to restore the identity of sound environment and expand the sound culture of a region, the purpose of this study are to excavate the resources of soundscape and find out the plans for the preservation and promotion of soundscape resources peculiar to the region. For this purpose, this research is conducted through an interview survey of residents and an observation survey using listening walk in Hongdo, one of the southwesten island of Korea. The results of survey confirm that there are so many sounds to hear around Hongdo island, those are, natural sounds such as the song of the birds, the roar of the waves, the whistling sounds, the shriek of the seagulls, and the pebbles sounds washed away by the waves, and artificial sounds such as the steam-whistle signals, the ship's broadcasts, the voice of tourists, the sounds of church bells, lighthouse sirens etc. The results suggest that it is necessary to consider several ways for restoration of an unique soundscape in Hongdo island, those are, improvement for efficient management of a ship's broadcasts in public areas, removal of a ferry in Hongdo swimming beach, management of Dangsanje (a religious service), preservation of a lighthouse siren and a foghorn, restoration and improvement of underground stream, management and control of public fish market, restoration of brooklet, management of cooperative system for a fish market, restoration of PoongO-Gut (a ritual for a large harvest) and a skate festival, management of a Hongdo sports meeting, sound quality modification of a boat whistle, restoration of orientalia such as a funeral bier, ecosystem preservation activity of the shore and ocean, and promotion of amenity for fascination and vitality in a rural community. Also, a sound map is drawn up for many tourists so as to realize the importance of sound environment and identity of soundscape and to gain their experience at first hand in Hongdo island.