• 한국전자파학회논문지
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• 제25권10호
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• pp.966-982
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• 2014

본 논문에서는 고속 디지털 시스템에서 발생하는 잡음에 의해 RF 시스템의 특성이 열화되는 현상(RF interference: RFI)에 관한 시스템 레벨의 EMC 분석 기술과 주요 잡음원인 고속 디지털 시스템에서의 EMC 대책 기술을 소개하고 분석하였다. 현재 하나의 전자기기에서 시스템 간 발생하는 EMI/EMC 문제는 더욱 심각해지고 있으며, 특히 디지털 시스템의 EMI에 의한 RFI 문제는 주요 관심 문제로 인식되고 있다. 따라서 본 논문에서는 현재까지 연구되어진 부품 레벨부터 시스템 레벨까지의 RFI 연구에 대하여 소개하고 분석하였다. 그리고 이 문제를 해결하기 위해서 주요 잡음원 중의 하나인 고속 디지털 인터페이스에서 발생하는 공통모드 잡음의 발생 원인과 그에 대한 대책 연구에 관하여 분석하였다. 마지막으로, 앞으로 RFI 문제를 해결하기 위한 시스템 레벨의 EMC 분석 및 대책 연구방향을 제시하였다.

• 정보보호학회논문지
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• 제24권6호
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• pp.1045-1053
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• 2014

본 논문에서는 카드 단말기로부터 발생할 수 있는 부채널 신호를 통해 금융 중요 정보의 누수가 발생할 수 있다고 가정하고, 실제 적용 가능한 공격 모델을 새로이 제안한다. 논문에서 제안하는 공격 모델은 소형 센서를 카드 단말기에 부착하여 카드 단말기에서 발생하는 진동 신호를 이용한 진동 신호 기반 부채널 공격이다. 이 소형 센서를 통해 카드결제 승인 단말기의 버튼을 누를 때 발생되는 진동신호를 알아낼 수 있으며, 이러한 정보는 금융 정보를 탈취하는 기반이 된다. 이러한 연구는 기존에 실시된 다른 부채널 연구들과 어느 정도 유사한 면도 있으나, 본 논문은 비언어적 모델을 기반으로 한다는 점에서 그 성격이 다르다. 왜냐하면 금융 결제에 필요한 카드 번호, 비밀번호, 휴대전화 번호 등은 일정한 패턴을 가질 수 없기 때문이다. 또한 소형 카드 단말기를 이용한 연구가 거의 없었다는 점에서 본 연구는 의미를 가진다. 이에 소형 무선 센서를 데이터를 수집하고, 데이터 특성을 고려해 주파수 영역의 스펙트럼 및 주성분 분석 방법을 이용한 통계적 신호처리 및 패턴 인식 알고리즘을 이용해 수집 정보를 분석을 실시한 뒤, 그 실험 결과를 선보인다.

• Applied Biological Chemistry
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• 제49권3호
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• pp.254-258
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• 2006

내분비계장애물질에 노출된 어류의 에스트로겐 활성에 대한 생물지표단백질인 vitellogenin을 검출하는 압전류적 면역센서를 잉어 vitellogenin에 대한 항체와 AT-cut 수정진동자를 생물요소와 변환기로 사용하여 구성하고 이를 이용한 잉어 vitellogenin 검출을 행하였다. 이형이기능성의 티올화 가교화제인 sulfosuccinimidyl 6-[3-(2-pyridyldithio)propionamido]hexanoate 처리에 의하여 티올화된 항체를 수정진동자상의 금전극에 화학흡착법에 의하여 고정화하여 센서 chip을 제조하였다. 센서반응을 위한 반응완충용액을 0.1M sodium phosphate(pH 7.4)로 선정한 후 $0.4864{\sim}486.4000\;nM$의 vitellogenin 용액을 가하였을 때 농도의존적인 센서반응의 증가가 나타났으며 이 때 잉어 vitellogenin에 대한 검출한계는 0.4864 nM로 추정되었다.

• Archives of Plastic Surgery
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• 제45권1호
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• pp.58-61
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• 2018

Background Venous anastomosis is an important component of digital replantation, but is not always feasible, as some cases require external bleeding to treat venous congestion in the replanted tissue. In the present study, we evaluated the relationship between the number of vein anastomoses and the survival rate of Tamai zone I replantations. Methods A retrospective review was performed of all patients who underwent replantation of a fingertip amputation between 2014 and 2016. Patient charts were reviewed for demographic information, the mechanism of injury, the number of venous anastomoses, and the use of anticoagulation, external bleeding, and/or leeches. The cohort was divided into 3 groups depending on the number of venous anastomoses: no veins (group 1), a single vein (group 2), and 2 or more veins (group 3). Survival rates and external bleeding rates were analyzed across the groups. Results The review identified 143 fingertip replantations among 134 patients. The overall survival rate was 94% (135 of 143). Failures were due equally to venous complications (n=4, 50%) and to arterial complications (n=4, 50%). Our analysis did not identify any correlation between the number of veins anastomosed and the replant survival rate (P=0.689). However, a greater number of anastomoses was associated with a significantly lower frequency of external bleeding (P=0.017). Conclusions The number of venous anastomoses was not correlated with the survival rate. However, a greater number of venous anastomoses was associated with a decreased need for external bleeding, corresponding to a significant decrease in the need for postoperative monitoring and leech therapy.

• 수산해양기술연구
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• 제34권1호
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• pp.52-61
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• 1998

We studied behaviour pattern of anchovy (Engraulis japonicus) shoal by a method of shoal echo integration and tested species identification by a method of artificial neural network using the acoustic data collected in the East China Sea in March 1994 and in the southern coastal waters of the East Sea of Korea in March 1995. Between areas, frequency distribution of 10 shoal descriptors was different, which showed characteristics of shoal behaviour in size, bathymetric position and acoustic strength. The range and mean of shoal size distribution in length and height was wider and bigger in the southern coastal waters of the East Sea than in the East China Sea. Relative shoal size of China Sea. Fractal dimension of shoal was almost same in both areas. Mean volume reverbration index of shoal was 3 dB higher in the southern coastal waters of the East Sea than in the East China Sea. The depth layer of shoal distribution was related to bottom depth in the southern coastal waters of the East Sea, while it was between near surface and central layer in the East China Sea. Principal component analysis of shoal descriptors showed the correlation between shoal size and acoustic strength which was higher in the southern coastal waters of the East Sea, than in the East China Sea. Correlation was also found among the bathymetric positions of shoal to some degree higher in the southern coastal waters of the East Sea than in the East China Sea. The anchovy shoal of two areas was identified by artificial neural network. The contribution factor index (Cio) of the shoal descriptors between two areas were almost identical feature. The shoal volume reverberation index (Rv) was showed the highest contribution to the species identification, while shoal length and shoal height showed relatively high negative contribution to the species identification.

• 패션비즈니스
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• 제9권5호
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• pp.37-50
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• 2005

The purpose of this study is to present basic data that can express beautiful silhouette by studying visual effect that depend on waist position of basic pants and the change of round belt width and analyzing the study of visual effect of the pattern design as well as the effect of design component. The stimuli are 21 samples: 7 variations of the location of the waistline and 3 variations of the width of the belt. The data has been obtained from 35 fashion design majors. The data has analyzed by frequency, factor analysis, anova, scheffe's test and the MCA method. The visual effects by the location of waistline and the width of belt are composed of 3 factors : horizontal direction factor, vertical direction factor and flexuosity factor. In these factors, horizontal factor is estimated by most important factor. Visual effect is positive when belt width widens as the location of waist line goes down to position of low belt. And in case the location of waist line is in the position of natural waist belt and low rise belt, belt of 3.2cm width is effective visually. The interaction effects between the location of the waistline and the width of the belt have significant differences in all factors. Factor that appears in visual effect of basic pants can be evaluated differently according to pattern of pants and characteristic of body shape. So we may receive better visual assessment if we consider the location of waist belt and width of belt in side of visual effect and image, when we produce pants giving variety to crotch depth.

• 비교문화연구
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• 제39권
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• pp.381-406
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• 2015

Russian nasal consonants / m /, / n / have a feature value not only [+consonant] in common with obstruents, but also [+sonorant] in common with vowels. Nasal / m /(bi-labial) and / n /(dental) have the same place of articulation but different manner of articulation. The feature value of / m / is [+cons, +son, +nas, +ant, -cor, -high, -low, -back, -cont, -del, rel, -strid, +voic], and that of / n / is [+cons, +son, +nas, +ant, +cor, -high, -low, -back, -cont, -del, rel, -strid, + voic]. There is a difference in feature [cor] value of / m / and / n /. In this study it is confirmed that it is a fact that the Russian nasal consonants behave differently from the other consonants in each phonological phenomenon due to their phonological characteristics. The preceding voiced obstruent is changed to an unvoiced one in a process where the last voiceless obstruent in the consonant cluster ' voiced obstruent + nasal /m/ + voiceless obstruent' skips the nasal consonant and spreads its feature value to the preceding voiced obstruent transparently because of the feature [+sonorant] of the nasal consonant. The coronal nasal /n/ participates in a palatalization with the following palatal actively and palatalize preceding plain consonants passively because of markedness hierarchy such as 'Velar > Labial > Coronal'. But the labial nasal /m/ is palatalized with the following velar palatal actively and participates in a palatalization with the following coronal palatal passively. This result helps us confirm the phonological difference of /m/ and /n/ in a palatalization. When the a final consonant is nasal, the unvoicing phenomenon of a final consonant doesn't occur. In such a case as cluster 'obstruent + nasal' the feature value [voiced] of the preceding obstruent doesn't change, but the following nasal can assimilate into the preceding obstruent. When continuing the same nasals / -nn- / in a consonant cluster, the feature value [+cont] of a weak position leads the preceding nasal / n / to be changed into [-cont] / l /. Through the analysis of the frequency of occurrences of consonants in syllabic onsets and codas that should observe the 'Sonority Sequence Principle', the sonority hierarchy of nasal consonants has been confirmed. In a diachronic perspective following nasal / m /, / n / there is a loss of the preceding labial stop and dental stop. But in clusters with the velar stop+nasal, the two-component cluster has been kept phonetically intact.

• 한국정보통신학회논문지
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• 제25권11호
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• pp.1687-1695
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• 2021

본 논문에서는 버틀러 매트릭스를 이용한 빔포밍 안테나를 설계 및 분석하였다. 제안한 빔포밍 안테나의 동작 주파수는 2.4 GHz의 ISM 대역이며, 빔포밍 안테나의 구성 요소는 1 × 4 배열 안테나 및 4 × 4 버틀러 매트릭스로 구성된다. 4 × 4 버틀러 매트릭스의 출력포트에 서로 다른 위상차를 갖는 신호가 출력되며, 신호는 1 × 4 배열 안테나의 각각의 입력포트에 공급된다. 4개의 입력포트를 갖는 빔포밍 안테나는 총 4개의 빔을 형성한다. 빔포밍 안테나의 방사패턴을 분석하기 위해 각각의 입력포트에 신호를 스위칭하여 공급하였으며, 입력포트 1 ~ 4에 대한 개별적인 분석을 진행하였다. 제안한 빔포밍 안테나는 각각의 입력포트에 따라 각각 -12°, 40°, -40°, 12° 방향에서 주 빔이 형성되었다.

• 통합자연과학논문집
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• 제14권1호
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• pp.1-5
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• 2021

라디오 진동수 스퍼터를 이용하여 실리콘(110) 기판위에 증착시간을 60분, 120분 그리고 180을 변화시켜서 산화아연 박막을 만들었다. ZnO₂ 박막의 입자 성장면을 X선 회절 장치를 써서 분석한 결과 박막의 주 성장면(002)면과 (103)면의 방향이 증착 시간의 영향을 많이 받았다. 전자 주사 현미경을 통하여 ZnO₂박막의 입자 성장을 관찰 한 결과 ZnO₂박막이 증착 초기에는 성장이 정체되는 인큐베이션 시간이 필요하다가 일정 시간이 지나면 다시 입자 성장이 일어나는 현상이 관찰 되었다. ZnO₂박막의 화학 분석을 한 결과는 증착 시간의 증가가 ZnO₂박막내의 산소의 양과는 변화가 없었지만 Zn의 성분에 변화가 관찰 되어서 박막의 증착 시간이 박막내의 Zn성분에는 영향을 미침을 알 수 있었다.

• Animal Bioscience
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• 제34권5호
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• pp.789-800
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• 2021

Objective: Conservation and genetic improvement of cattle breeds require information about genetic diversity and population structure of the cattle. In this study, we investigated the genetic diversity and population structure of the three cattle breeds in the Korean peninsula. Methods: Jeju Black, Hanwoo, Holstein cattle in Korea, together with six foreign breeds were examined. Genetic diversity within the cattle breeds was analyzed with minor allele frequency (MAF), observed and expected heterozygosity (HO and HE), inbreeding coefficient (FIS) and past effective population size. Molecular variance and population structure between the nine breeds were analyzed using a model-based clustering method. Genetic distances between breeds were evaluated with Nei's genetic distance and Weir and Cockerham's FST. Results: Our results revealed that Jeju Black cattle had lowest level of heterozygosity (HE = 0.21) among the studied taurine breeds, and an average MAF of 0.16. The level of inbreeding was -0.076 for Jeju Black, while -0.018 to -0.118 for the other breeds. Principle component analysis and neighbor-joining tree showed a clear separation of Jeju Black cattle from other local (Hanwoo and Japanese cattle) and taurine/indicine cattle breeds in evolutionary process, and a distinct pattern of admixture of Jeju Black cattle having no clustering with other studied populations. The FST value between Jeju Black cattle and Hanwoo was 0.106, which was lowest across the pair of breeds ranging from 0.161 to 0.274, indicating some degree of genetic closeness of Jeju Black cattle with Hanwoo. The past effective population size of Jeju Black cattle was very small, i.e. 38 in 13 generation ago, whereas 209 for Hanwoo. Conclusion: This study indicates genetic uniqueness of Jeju Black cattle. However, a small effective population size of Jeju Black cattle indicates the requirement for an implementation of a sustainable breeding policy to increase the population for genetic improvement and future conservation.