• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.415-416
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• 2008

We demonstrate a simple method to multiply the repetition rate of an optical pulse train by a fiber Fabry-Parot interferometer (FFPI) spectral filtering. A stable 40 GHz pulse train at 1550 nm is successfully generated by removing unwanted spectral components of a 10 GHz actively mode-locked laser source by passing a high finesse FFPI.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2009년도 추계학술대회
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• pp.657-665
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• 2009

The paper reviews gauge R&R studies by two-factor mixed models including random and fixed factors. The two-factor mixed models include restricted models and unrestricted models considering the interaction of two factors. This study also classifies the models according to the number of factors, and the combination of various factors such as random factor, fixed factor, block factor and repetition type.

• 대한후두음성언어의학회지
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• 제12권1호
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• pp.55-60
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• 2001

Background and Objectives : Syllable Maximum Repetition Rate(MRR) is ability to repeat rapidly the articulators and is assessed for oromechanism function as one of the MPT. MRR is measured by rate(counts/sec), also simultaneously considered accuracy and consistency. The objective of the present was to examine stimuli effects and age and sex differences for MRR. Materials and Method : This study was participated 60 normal males and females(1 : 1) who were divided into two groups young(<40 years old) and old($\geq$40 years old). Stimuli were $/{P^=}a/,/{t^=}a/,/{k^=}a/,/{P^h}a/,/{t^h}a/,/{k^h}a/,/{P^=}{at^=}{ak^=}a/$ for, manner(tense and aspirated) of articulation, $/{p^h}{at^h}{ak^h}a/,/{t^h}{ap^h}{ak^h}a/$ for the effect of the order of syllable, glide /u-i/ for coordination of lip and tongue, interrupted vowel /i/ for laryngeal function. Results : There were little differences in two age groups and sex and manner of articulation for MRR tasks. The fastest average MRR of the single syllable included in this study was $/{t^=}a/$. significant differences existed between MRR for ${p^h}{at^h}{ak^h}a/ and /{t^h}{ap^h}{ak^h}a/$, which suggested that MRR was affected by the order of the syllables. MRR for interrupted vowel /i/ was about 2 counts/sec slower than average rate of 1 syllables. Conclusion : From these results, the order of the syllables was a crucial variable in MRR. rather than age or sex. There were no difference age, sex and manner of rate. The interrupted vowel repetition rate was slightly slow used and can provide basic information to assess the speech mechanism and can be useful to develop effective stimuli to differentiate the disordered group from normal.

• 한국통신학회논문지
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• 제28권12C호
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• pp.1192-1199
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• 2003

본 논문에서는 다중경로 채널 환경에서 펄스 반복 빈도 (pulse repetition frequency, PRF)와 슬롯 시간이 UWB (ultra wide band) 무선 통신 시스템의 데이터 전송율 (throughput) 성능에 미치는 영향을 조사하고 이를 기반하여 유효 데이터 전송율이 최대화되도록 하는 PRF와 슬롯 시간을 이용한 전송율 제어를 제안한다. 최근에 UWB 시스템이 갖고 있는 장점으로 인하여 근거리 고속 무선 데이터 전송과 관련하여 관심이 고조되고 있다. UWB 시스템에서는 데이터 전송율을 결정짓는 파라미터로는 펄스를 반복하는 펄스 반복 회수와 펄스간의 간격을 결정짓는 슬롯 시간을 들 수 있다. AWGN이 존재하는 다중경로 채널 하에 있는 UWB 시스템은 펄스간의 간섭(inter-pulse interference, IPI)과 잡음에 의하여 시스템 성능이 저하된다. UWB 시스템은 이 두 파라미터의 조정을 통하여 시스템의 성능을 유지 또는 개선할 수 있다. 본 논문에서는 두 파라미터의 변화가 다양한 채널 환경에서 데이터 전송율에 미치는 영향을 모의실험을 통하여 관측하고 이를 기반하여 설계된 가변 전송율을 사용하는 것이 비가변적인 방법에 비하여 유효 데이터 전송율 측면에서 우수함을 모의실험을 통하여 검증하였다.

• 한국인지과학회:학술대회논문집
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• 한국인지과학회 2005년도 춘계학술대회
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• pp.151-153
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• 2005

We investigated the brain substrate of repetition priming on the implicit memory taskusing low-resolution electromagnetic tomography (LORETA) with high-density 128 channel EEG and individual MRI as a realistic head model. Thirteen right-handed, healthy subjects performed a word/nonword discrimination task, in which the words and nonwords were presented visually,and some of the words appeared twice with a lag of one or five items. All of the subjects exhibited repetition priming with respect to the behavioral data, in which a faster reaction time was observed to the repeated word (old word) than to the first presentation of the word (new word). The old words elicited more positive-going potentials than the new words, beginning at 200 ms and lasting until 500 ms post-stimulus. We conducted source reconstruction using LORETA at a latency of 400 ms with the peak mean global field potentials and used statistical parametric mapping for the statistical analysis. We found that the source elicited by the old words exhibited a statistically significant current density reduction in the left inferior frontal gyrus. This is the first study to investigate the generators of repetition priming using voxel-by-voxel statistical mapping of the current density with individual MRI and high-density EEG.

• 인지과학
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• 제18권4호
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• pp.371-398
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• 2007

이 연구는 의미점화과제와 반복점화과제를 사용하여 사용빈도와 의미투명성이 복합명사의 분리처리 양상에 어떤 영향을 미치는지를 알아보았다. 실험 1에서는 사용빈도에 따라 복합명사의 분리처리 양상이 달라지는지를 검토하였다. 의미점화효과가 복합명사 연상어 조건에서 자극제시시차나 사용빈도와 무관하게 관찰되었으며, 반복점화효과는 부분조건과 전체조건에서 모두 관찰되었지만 부분조건에서 더 큰 반복점화효과를 보였다. 이 결과는 복합명사가 하위 형태소로 분리되어 처리되는 경로와 복합명사 전체로 처리되는 경로가 함께 존재할 가능성을 보여준다. 실험 2에서는 의미투명도에 따라 복합명사의 분리처리 양상이 달라지는지를 검토하였다. 의미점화효과가 복합명사 연상어 조건에서 자극제시시차나 의미투명도에 무관하게 관찰되었으며, 반복점화과제에서도 실험 1b와 유사한 결과를 보였다. 실험 1과 2의 결과는 어휘수준에서 분리처리경로와 전체처리경로를 통해 활성화된 의미가 개념 수준에서 이루어지는 상호작용과정을 통해 복합명사의 의미를 결정함을 시사한다.

• 한국지역사회생활과학회지
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• 제18권3호
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• pp.391-398
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• 2007

Ginkgo leaves, which have been known as medical materials, were selected as new natural dyes in this study, in which it was examined whether they have the function of UV-blocker or not. Cotton, linen & Hanji(Korean traditional paper) were dyed with Ginkgo. Al, Cr, Cu, Fe and Sn were selected as mordants. UV-blocking rate of dyed samples was measured after dyeing and mordant treatment. The results of this study are as follows. First, most surface color of dyed samples was yellow except that Hanji mordanted with Cu was yellowish red. Second, dyeing repetition had positive correlations with K/S values of cotton ($r=.\;758^{**}$), linen ($r=.\;500^*$) and Hanji ($r=.\;819^{**}$), because K/S values were increased according to dyeing repetition. Third, solar UV-blocking rates had positive correlations with dyeing repetitions (p<0.01), because UV-blocking rates had increased according to dyeing repetition. Fourth, UV-blocking ability of Hanji was highest among samples, as UV-blocking rates of cotton and linen dyed after 3 dyeing repetition were up to 93%, Hanji's values were up to 98%. Therefore, it was proven that Ginkgo extracts used in this experiment as dyestuff have excellent dyeing ability and high UV-blocking ability. It is hoped that this work will lead to further research to confirm the physiological effects when human wear the clothes made from Hanji.

• 한국의류산업학회지
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• 제10권5호
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• pp.690-701
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• 2008

Fashion illustration as conversational pattern which is made up of human and daily story creates brand image and new cultural value in textile design. The purpose of this study is to analyze an expressive characteristics focused on human body in conversational pattern illustration. The method of this study was to analyze documentaries, fashion magazines and internet fashion web site. The results were as follows: The category of body expression was classified as the head, the bust, the whole body, and the others. Most of all, the head is higher frequency than any other part. The category of body type was classified as iconic reappearance and surreal fantasy. The former expressed gender images of woman and man in reality and showed high frequency of 90.41%. Above all, two types were to show the organic correlation between fashion illustration body and brand concept. The construction method of motif was classified as singleness of body, repetition of body, singleness of body and non-body mixed, and repetition of body and non-body mixed. The repetition of body showed low frequency and it was composed of regular repetition construction and irregular construction. The singleness of body and non-body mixed, showed the highest frequency and it was definitely to communicate fashion concept. In these days, conversational pattern illustration in modern fashion pattern strengthens brand identity and informs the fashion image as creative commercial art. And also, it satisfies cultural sensibility of consumer and categorizes public phenomenons in our times.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1060-1062
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• 1999

Pulsed Nd:YAG laser is used widely for materials processing and instrumentation. It is very important to control the laser energy density in materials processing by a pulsed Nd:YAG laser. A pulse repetition rate and a pulse width are regarded as the most dominant factors to control the energy density of laser beam. In this study, the alternating charge-discharge system was designed to adjust a pulse repetition rate. And the parallel mesh is added to increase laser output power. This system is controlled by one chip microprocessor and allows to replace an expensive condenser for high frequency to a cheap condenser for low frequency. In addition, we have investigated the current pulse shape of flashlamp and the operating characteristics of a pulsed Nd:YAG laser. As a result, it is found that the laser output of the power supply using the parallel mesh and the alternating charge-discharge system is not less than that of typical power supply. As the pulse repetition rate rises from 10pps to 110pps by the step of 20pps at 1000V and 1200V, it is found that the laser efficiency decreases but the laser output power increases about 5W at each step.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2204-2206
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• 1999

Pulsed Nd:YAC laser is used widely for materials processing and instrumentation. It is very important to control the laser energy density in materials processing by a pulsed Nd:YAG laser. A pulse repetition rate and a pulse width are regarded as the most dominant factors to control the energy density of laser beam. In this study, the alternating charge-discharge system was designed to adjust a pulse repetition rate. This system is controlled by one chip microprocessor and allows to replace an expensive condenser for high frequency to a cheap condenser for low frequency. In addition. we have investigated the current pulse shape of flashlamp and the operating characteristics of a pulsed Nd:YAG laser. As a result, it is found that the laser output of the power supply using the alternating charge-discharge system is not less than that of typical power supply. As the pulse repetition rate rises from 30pps to 120pps by the step of 30pps at 1200V, it is found that the laser efficiency decreases but the laser output power increases about 6W at each step.