• Journal of the Korea Society of Computer and Information
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• v.18 no.9
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• pp.1-10
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• 2013

In this paper, we implement the SIFT(Scale-Invariant Feature Transform) algorithm for feature point extraction using a many-core processor, and analyze the performance, area efficiency, and system area efficiency of the many-core processor. In addition, we demonstrate the potential of the proposed many-core processor by comparing the performance of the many-core processor with that of high-performance CPU and GPU(Graphics Processing Unit). Experimental results indicate that the accuracy result of the SIFT algorithm using the many-core processor was same as that of OpenCV. In addition, the many-core processor outperforms CPU and GPU in terms of execution time. Moreover, this paper proposed an optimal model of the SIFT algorithm on the many-core processor by analyzing energy efficiency and area efficiency for different octave sizes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.1
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• pp.28-36
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• 1974

For the development of acoustic fishing method, we had been researched a fundamental study which concerned on the sound production and behaviour of crabs was conducted. For specimen crabs such as Portunus trituberculatus and Charybdis japonica were selected. Croaking noise were recorded by the Cassette-recorder (Sony model CF-1600) through the under water monitor microphone, and analyzed in frequencies by Octave band analyzer, Rion SA-55, and sound pressure level of source by sound level meter, SM-5844. The following are the results obtained from the present investigations : When sound production of crabs (Portunus trituberculatus( female ) : carapace width $12.6\~15$cm) were attracted to another crabs in the water of anechoic aquarium, efficacy of phonotaxis was $84\~100\%$ and velocity by phonotaxis was $6.5\~7.2cm/sec$. The time required for copulation ranged from 90 minute to 95 minutes by Charybdis japonica, at that time there was no sound production with their copulation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.4
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• pp.789-794
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• 2011

A coaxial-cable impedance transformer used in wideband frequency range is generally restricted to the fixed impedance transformation ratio as n2:1 or 1:n2(n: the number of coaxial cables). In this paper, we propose a new coaxial-cable impedance transformer to have an arbitrary impedance transformation ratio. We have fabricated three impedance transformers($50-{\Omega}$ to $25-{\Omega}$, $50-{\Omega}$ to $20-{\Omega}$ and $50-{\Omega}$ to $9-{\Omega}$) to confirm the operation characteristic of the suggested impedance transformer. The reflection characteristics (S11) of the fabricated $50-{\Omega}$ to $25-{\Omega}$ and $50-{\Omega}$ to $20-{\Omega}$ impedance transformer were less than -15dB over about 3-octaves frequency range and the reflection characteristic (S11) of the fabricated $50-{\Omega}$ to $9-{\Omega}$ impedance transformer was less than -15dB over about 1-octave frequency range, respectively.

• The Korean Journal of Community Living Science
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• v.27 no.2
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• pp.281-294
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• 2016

This study was conducted to promote consumer interest in Geothermal Heat Pump (Ground Source Heat Pump, GSHP) and district heating and cooling (District Heating & Cooling, DHC) systems, which are competing with each other in the heating and cooling field. Considering not only the required cost data of energy itself, but also external influence factors, the optimal mix ratio of these two energy systems was studied as follows. The quantitative data of the two energy systems was entered into a database and the non-quantitative factors of external influence were applied in the form of coefficients. Considering both of these factors, the optimal mix ratio of GSHP and DHC systems and minimum Life Cycle Cost (LCC) were obtained using an algorithm model design. The Optimal Energy Mix of GSHP & DHC (OEMGD) algorithm was developed using a software program (Octave 4.0). The numerical result was able to reflect the variety of external influence factors through the OEMGD algorithm. The OEMGD model found that the DHC system is more economical than the GSHP system and was able to represent the optimal energy mix ratio and LCC of mixed energy systems according to changes in the external influences. The OEMGD algorithm could be of help to improve the consumers' experience and rationalize their energy usage.

• 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.

• Proceedings of KOSOMES biannual meeting
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• 2006.05a
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• pp.207-212
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• 2006

The noise levels on board ship recognized at Europe in the early 1970s and the noise regulations on board ship began to put in a statutory form. After that, in 1982 "International Code on Noise Levels on Board Ships" adopted by IMO and it became standard to the newly built ship and remain so to this day. Especially, the ship engine room, which have huge main engine and various kinds of subsidiary machines, is under an extremely loud condition and so the worker who works in it is easy to lose his hearing. Recently, each nation regulates the allowable noise exposure time by law to protect the industrial employee from the occupational hardness of hearing. In our country, the allowable noise exposure time is regulated by the labor standard law but the international provisions regulated by IMO have been applied in case of the ship engine room. In this paper, the cabin's noise levels of cargo-passenger ships plies south-west coast line were investigated.

• The Journal of the Acoustical Society of Korea
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• v.9 no.3
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• pp.11-23
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• 1990

In order to investigate the acoustical characteristics of the Hae-keum (Korean traditional musical instrument) tone quality, the spectrum and wave form of Hae-keum sounds were analyzed by the FFT Analyzer. The analysis was carried out by the varying of the tension of Hae-keum strings, the positions of bridge and the top plate's thickness of Hae-keum respectively. According to the experiment, the following results are obtained ; the over tone's amplitude nearby the top plate resonance frequency is greater than the fundamental tone's amplitude because the top plate resonance frequency is higher than the fundamental tone's frequency. Tone qualities are better when the bridge is situated in the middle of top plate and the tension of strings is larger. The inharmonicity coefficient of the Hae-keum's second string is 0.049 cents/$n^2$. The brilliance and richness is poor, because we seldom found the over tone over 5kHz and the inharmonicity of the Hae-keum is greater than that of a violin. Also we confirmed that we are able to get the best tone quality in 4.5mm thickness of the Hae-keum's top plate.

• The Journal of the Acoustical Society of Korea
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• v.19 no.7
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• pp.59-65
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• 2000

This paper describes the analysis of vibration characteristics through the human body as the research for voice therapy and diagnosis. The oscillation signal is not external forces but the self-voice to be pronounced the vowels ('a', 'e', 'i', 'o', 'u'). The experiment system consists of microphones, accelerometers and amplifiers. The input data are stored by the computer. At the same time, the voice is stored by the microphone and the vibration signal of the human body is stored by accelerometer. The 63 points are appointed in head, neck, trunk of human body. The positions and number of times are changeable by the purpose. The analysis parameters are amplitude, phase, fundamental. frequency, formant and the correlation of vibration signal and voice is measured by coherence function. The results show that the vibration signals have characteristic vibration in the positions of human body.

• Speech Sciences
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• v.10 no.2
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• pp.111-128
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• 2003

Aerodynamic study is valuable information about the vocal efficiency in translating airflow to acoustic signal. The purpose of this study was to investigate the differences between trained singers and untrained controls under different two pitch by simultaneous using the airway interruption method and electroglottography (EGG). Under singing a Korean lied 'Gene', 20 (Male 10, Female 10) trained singers were studied on two one-octave different tone. Mean flow rate (MFR) , subglottic pressure (Psub) and intensity were measured with aerodynamic test using the Phonatory function analyzer (Nagashima Ltd. Model PS 77H, Tokyo, Japan). Closed quotients (Qx), jitter and shimmer were also investigated by electroglottography using Lx speech studio (Laryngograph Ltd, London, UK). These data were compared with those of normal controls. MFR and Psub were increased on high pitch tone in all subject groups. Statistically significant increasing of Qx and intensity were observed in male trained singers on high pitch tone (Qx;p = .025, intensity;p < .001). Beacasue of increasing of Qx and intensity, vocal efficiency was also significantly increased in male singers (p < .001). The trained singers' phonation was more efficient than untrained singers. The result means that the trained singers can increase the loudness with little changing of mean flow rate, subglottic pressure but more increasing of glottic closed quotients.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.5
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• pp.9-17
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• 2010

This paper presents a localization perception of a phantom sound image for ultrahigh-definition TV with respect to various loudspeaker configurations; two-horizontal, two-vertical and triplet loudspeakers. Vector base amplitude panning algorithm with modification for non-equidistant loudspeaker setup is applied to create the phantom sound image. In order to practically study the localization performance in real situation, the listening tests were conducted at the on-axis and off-axis positions of TV in normal listening room. A method of adjustment which can reduce the ambiguity of a perceived angle is exploited to evaluate the angles of octave-band signals. The subjects changed the panning angle until the real sound source and virtually panned source were coincident. A spatial blurring can be measured by examining the differences of the panning angles perceived with respect to each band. The listening tests show that the triplet panning method has better performance than vertical panning in view of perceptual localization and spatial blurring at both on-axis and off-axis positions.