• 한국콘텐츠학회논문지
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• 제11권3호
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• pp.477-486
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• 2011

본 논문에서는 컴퓨터 사용 시간과 시력 저하 관계를 분석했다. 우선 첫째로, 조사에 참여한 학생들을 성별, 학년, 시력과 안경 착용으로 인구학적 특성에 따라 분류 하였다. 설문은 컴퓨터 사용 시간, 시력 저하의 요인들, 그리고 컴퓨터 사용 목적에 관한 질문들을 하였다. 학생들의 연간 시력 변화와 시력 변화의 원인에 대해서 교차 분석한 결과, 설문에 참가한 165명의 학생 중 63.6%가 한 해 동안 시력이 나빠졌다. 컴퓨터 사용시간과 시력 저하 상관관계를 나타내기 위해 회귀 분석한 결과 일일과 주간 컴퓨터 사용에서는 시력저하를 나타냈고, 년 컴퓨터 사용에서는 시력저하를 나타내지 않았다. 또한 독립 표본 T검정으로 안경 착용과 미착용자의 컴퓨터 사용 시간과 시력 저하를 분석한 결과 일일과 주간 컴퓨터 사용에서는 시력저하를 나타냈고, 년 컴퓨터 사용에서는 시력저하를 나타내지 않았다. 그런데 안경 미 착용자가 안경 착용자에 비해서 시력 저하를 더 나타냈다. 본 논문에서는 24.5%의 학생들이 컴퓨터 사용으로 시력저하를 나타냈다. 컴퓨터 사용 용도의 빈도분석 결과에서는 컴퓨터 게임이 36.4%로 가장 많았고, 그 다음으로 학습목적이 32.1% 나타났다. 본 논문에서는 컴퓨터 사용 시간과 시력 저하의 요인 분석을 통해 컴퓨터 사용 시간이 시력저하에 상관관계가 있음을 나타낸다. 따라서 학생들의 컴퓨터 사용에 대한 학부모님들의 관심이 필요하다.

• 한국컴퓨터정보학회논문지
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• 제18권11호
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• pp.145-151
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• 2013

본 논문에서는 주차 시설 이용 현황 중 하나인 차량 번호판 조사를 수행하도록 한다. 차량 번호판 조사는 주차 차량이 얼마나 오랫동안 주차해 있었는지를 파악한다. 또한 주차 회전율 과 평균 주차 지속 시간 등의 파악에 매우 편리한 방법이다. 관찰자가 없이 카메라를 이용하여 조사 시간 간격을 주어 조사하도록 한다. 조사 시간 간격을 각 주차된 차량에 부여하여 평균 주차 지속 시간을 결정하도록 한다. 또한 주차면 1개당 1시간당 주차 차량 대수인 주차 회전율을 조사한다. 이렇게 구해진 주차 지속 시간은 주차 시설을 비효율적으로 사용하고 있는 부분을 찾아내는데 중요하다. 주차 회전율 또한 주차장의 효율성을 검토하는 중요한 요소이다. 실험을 통하여 주차장의 주차 지속 시간과 주차 회전율을 파악했다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권12호
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• pp.2272-2293
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• 2011

Communication technology of future networks is predicted to provide a large variety of services including WiFi service in vehicular network. In this paper, we assume that vehicles are embedded with WiMAX antenna and in-vehicle terminals receive WiMAX traffic through WiFi interface. This assumption will impose severe performance degradation due to interference among mobile BSSs when WiFi access points (APs) are densely located. Existing interference avoidance techniques cannot properly resolve the above problems and do not cope with dynamically moving vehicular scenario since they focus only on the fixed network topology. In this paper, we propose a mobility-aware interference avoidance scheme for WiFi services. The proposed scheme computes the interference duration by exploiting mobility vector and location information of neighboring APs. If the interference duration is not negligible, our scheme searches for another channel in order to avoid interference. However, if the interference duration is negligible, our scheme continues to use the channel to reduce switching overhead. To measure the effectiveness of the proposed scheme against other existing techniques, we evaluated performance by using OPNET simulator. Through the simulation, we obtained about 60% reduction in the maximum interference frequency and about 67% improvement in throughput. Furthermore, our scheme provides fair channel usage.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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• pp.937-942
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• 1994

Text-to-Speech(TTS) conversion system can convert any words or sentences into speech. To synthesize the speech like human beings do, careful prosody control including intonation, duration, accent, and pause is required. It helps listeners to understand the speech clearly and makes the speech sound more natural. In this paper, a prosody control scheme which makes use of the information of the function word is proposed. Among many factors of prosody, intonation, duration, and pause are closely related to syntactic structure, and their relations have been formalized and embodied in TTS. To evaluate the synthesized speech with the proposed prosody control, one of the subjective evaluation methods-MOS(Mean Opinion Score) method has been used. Synthesized speech has been tested on 10 listeners and each listener scored the speech between 1 and 5. Through the evaluation experiments, it is observed that the proposed prosody control helps TTS system synthesize the more natural speech.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.306-309
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• 2000

We developed an electronic music glove (EMG) system that could play musical scores in real time processing. The EMG system interfaces with the signal coming from the controller to the sound card in the computer. The computer, according to the status of the finger and foot switches, generates the signals to the speaker systems using the application C++ program by making use of MIDI message. The EMG systems can control up to several octave notes and duration of sound, and several musical performance expressions such as chorus, reverberation, rhythm, and volume. Finally, our EMG could play the performance of simple music depending on the choice of any kind of musical instruments in the sound card in computer systems.

• 통합자연과학논문집
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• 제13권4호
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• pp.121-127
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• 2020

To investigate the effects of wearable near-infrared ray-emitting knee pads on knee pain among elderly adults in Korea. Randomized controlled trial evaluating the effects of near-infrared rays (NIR) on knee pain in Korean elderly adults. Five community-based research facilities (two welfare centers, a senior citizen center, and two churches). Forty-seven participants aged 65 years and older who had experienced knee pain. The experimental group (n = 25) wore NIR-emitting knee pads for one month at nighttime while sleeping. The control group (n = 22) wore knee pads without NIR. Demographic characteristics, intensity and duration of knee pain, amount of analgesic medication used, range of motion, gait speed, and health-related quality of life were collected using questionnaires. The experimental group showed decreased intensity (t = -6.17, p < 0.001) and duration (t = -3.34, p = 0.002) of knee pain and reduced analgesic use (t = -2.30, p = 0.026) compared to the control group. NIR may be an effective non-pharmacological option for relieving knee pain in elderly adults.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 기술교육전문연구회
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• pp.96-102
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• 2003

Today, stage technology is developing highly by application of digital computer. Performance is composed of audio/video and acoustic technology takes very important position in field of stage technology. Generally speaking, four factors of sound are loudness, pitch, sound timbre and duration. Loudness depends on sound pressure level, yet partly related with spectrum and dulation. Pitch depends mainly on frequence and have a relation with sound pressure and duration. sound timbre depends strongly on spectrum and have a relation with frequence. In this paper, I designed a multi-microphone system which can used in broadcasting and performance stage with vicboss 200MHz-VHF wireless microphone and vicboss 900MHz-VHF wireless microphone. I also studied about multi-microphone which can use conveniently in the super play that needs many microphones. If this multi-microphone is prodused, we could expect better sound quality and a big progress in stereo recording technology.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제10권1호
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• pp.7-11
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• 2010

In this paper, we propose an improved speech/music discrimination method based on a feature combination and dimensionality reduction approach. To improve discrimination ability, we use a feature based on spectral duration analysis and employ the hierarchical dimensionality reduction (HDR) method to reduce the effect of correlated features. Through various kinds of experiments on speech and music, it is shown that the proposed method showed high discrimination results when compared with conventional methods.

• 한국정보과학회논문지:정보통신
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• 제29권2호
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• pp.181-187
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• 2002

Connection admission control(CAC), which decides whether or not to accept a new call request, is one of the most Important preventive congestion control techniques in asynchronous transfer mode(ATM) networks. To develop a practical CAC scheme, first we propose a "Modified Cell Loss Probability MP${\nu}"$, which is based on "Virtual Cell Loss Probability P${\nu}"$, taking into account mean burst duration of input traffic source and buffer size in ATM networks. MP${\nu}"$ computes more accurate cell loss probability than P${\nu}"$ without increasing computational complexity, since P${\nu}"$ is formulated simply form the maximum and the average cell rate of input traffic. P${\nu}"$ is overestimated as compared to the real cell loss probability when the mean burst duration is relatively small to the buffer capacity. Then, we Propose a CAC scheme, based on "Modified Virtual Bandwidth(MVB)" method, which may individualize the cell loss probabilities in heterogeneous traffic environments. For the proposed approach, we define the interference intensity to identify interferences between heterogeneous traffic sources and use it as well as MP${\nu}"$ to compute MVB. Our approach is well suitable for ATM networks since it provides high bandwidth utilization and guarantees simple and real time CAC computation for heterogeneous traffic environments.heterogeneous traffic environments.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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• pp.637-640
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• 1986

The design and use of a micro-computer-based system for quantitative study of ocular kinetics are described. An algorithm for microcomputer analysis of electro-oculographically recorded saccadic eye movement is presented. From a brief, 4-min recording session detailed statistical information about saccade amplitude, duration, and velocity can be obtained. Since this data is not significantly altered by practice of motivational factors, it provides a sensitive functional test of the oculomotor system and its brain control system.