• 한국환경과학회지
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• 제1권2호
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• pp.33-48
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• 1992

Since November 1990, the observations of methane (CH4) level have been carried out at Tae-ahn Peninsula (TAP) in Korea. Analysis on atmospheric data obtained in the period from November 1990 to August 1992 is carried out and the results are included in this study. We 임ole that CIL does not have a clear seasonal cycle with a minor maximum in August- september and with a minimum in June-July. The variations in monthly average level are much larger with 1765.01∼ 1857.21 pub (amplitude 92.20 ppb). The occurrence of a minimum in June-July is due to the inflow of the North Pacific air, an increase of OH radical and due to a decrease in CH4 emission from rice paddy. A maximum in August and September appears to result from an increase in organic materials in agriculture (rice paddy) and forests, inputs of local sources due to weak airflows, stagnation of the warm and moist air and from a decrease in OH radical.'rho present analysis indicates that according to CH4 data from Mongolia and from several sites in North Pacific TAP is influenced as much as 31 pub in average from the inputs of Chinese omission. When the atmospheric CH4 of TAP is compared with data observed at Korea National University of Education (KNU), the values of KNU are higher (127 ppb) than those of TAP. It is clear that air samples taken at KNU are influenced strongly by local sources in central Korea than those at TAP. According to analysis of trajectories and airflows, we find that there are 4 types in classification. Firstly, when an air flow is originated mainly in China values of CH4 gas are in medium ranges. Secondly, when an airflow is from both local (Korea) and China we find higher values. Thirdly, with an airflow from both local (Korea) and Japan origins medium values are recorded. Fourths)r, when an airflow of maritime origin arrives low values of atmospheric CH4 are observed at TAP.

• 한국의류산업학회지
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• 제19권5호
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• pp.569-578
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• 2017

The purpose of this study is to analyze the lower body shape of varus-typed elderly women. This study intentionally collected elderly women at age 65 years or older who seemed to have a lower body shape of varus-type, and the data of 100 women were used for final analysis. The results are as follows. Elderly women with a lower body shape of varus-type were shorter than regular elderly women and had small circumference and weak lower body. To classify the body shapes, factor analysis was conducted which drew a total of 3 factors, with 74.11% of accumulative variance. Cluster analysis was performed according to factor analysis and the body shapes were divided into 3 types. Type 1 was a body shape with the most severe varus-type that had small measured values of height and the highest BMI. Type 2 was a group of women with a large build with a relatively small tendency of varus-type. Type 3 was a group of women who were not obese, had long lower bodies, and varus-type with small circumference, which were similar to Type 1. Therefore, this study on the body shape is expected to be used as a basic data for the development of the clothes for straightening the varus-typed lower body shape in the future.

• 자원환경지질
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• 제23권1호
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• pp.35-57
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• 1990

This study has been carried out on the Pegmatites, Naedeogri Granites, Nonggeori Granites and Metasedimentary rocks in the middle area of Taebaeksan region to investigate the geochemical properties and possibility of productivity. Pegmatites are characterized by metamorphosed anatectic pegmatite and differentiated magmatic pegmatite, and are mixed type of rare-element pegmatite and mica-bearing pegmatite by the classification of Ginsburg(1979). The petrological type of the igneous rocks is thought to be calcalkali, subalkaline and peralumious. According to chemical variations against D. I., differentiation trends from Naedeogri and Nonggeori Granites through non-mineralized pegmatites to mineralized pegmatites are supposed. From the relationship between oxided and $SiO_2$, pegmatites and Nonggeori Granite have shown similar tendencies and bulk composition of pegmatites and similar to metasedimentary rocks near the intrusives. By judging the correlations of trace elements, it is elucidated that pegmatites adjacent to Naedeogri and Nonggeori Granites have been originated in magma differentiation from these granites and the others have been differentiated by remelting or partial melting from metasedimentary rocks. $Sp_5$, $Sp_8$, and $Sp_9$ pegmatites are considered as productive rocks, and $Sp_4$, $Sp_6$, $Sp_7$, $Sp_{10}$, $Sp_{11}$, and $Sp_{12}$ pegmatites and granites are supposed to have a weak productivity, in terms of element ratios related with Sn mineralizations. Tourmalines in productive pegmatites are formed under the circumstance of Li-poor granitoids and associated with pegmatites, and the others are seemed to be originated in metapelites and metapsammites which are not coexisting with an Al-saturating phase. Three types of chemical zoning are noticed in tourmalines: (1) apparently homogeneous compositional patterns, (2) a continuous core-to-rim zoning and, (3) a discontinuous core-to-rim zoning. From results of EPMA of tourmalines, Al, Mg and Ca increase closer to rim, while Fe decreases.

• 디자인학연구
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• 제19권3호
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• pp.131-142
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• 2006

The purpose of this study is to develop an online community construct, which proposes an inclusive illustration of the structure of online communities, for online community designers. This study reviewed researches from psychology, sociology, management engineering, and practical reports to understand the characteristics and dynamics of online communities. The proposed online community construct visualizes the cognitive, affective, and behavioral aspects of online community. As the notion of community originates from geographical groups, and with the assumption that geographical community shares identical characteristics with online community, this study reviewed researches about geographical communities as a starting-point. Then the study went through three main perspectives (1) online community attributes, (2) sense of online community and (3) challenges of online community. Then this study proposed an online community construct that encompasses the reviewed frameworks. The online community can be seen as a congregation of members from two sources. One is from the 'Shared Goal' that meets the personal needs. Given the shared goal, members gather into the community without personal relationship and have more chances to feel the sense of belonging to their needs fulfillment or benefit. This befitting tendency leads to strengthening of membership. Public online forums fall under this classification. The other source is from the emotional connections that are already initiated by personal and casual contacts in the real world. The network of emotional connection can evolve into an online congregation of people under faint boundaries. Although there is no (or weak) shared goal, members are strongly bound to other members. Personal homepage or web log (blog) can be classified as an example of relationship-oriented community.

• 한국정보과학회논문지:소프트웨어및응용
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• 제34권12호
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• pp.1037-1044
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• 2007

최근 내용 기반 음악 검색 시스템에서는 사용자의 응답 시간을 단축시키기 위해 음악의 대표성을 갖는 선율을 추출하여 색인하고, 검색 시 이를 사용한다. 기존 연구에서는 미디(midi) 데이타를 이용하여 대표 선율을 추출하는 방법이 제안되었으나, 미디 데이타에 한정되는 단점이 있었다. 따라서 본 논문에서는 디지털 신호처리를 이용하여 모든 오디오 파일 포맷에 적용 가능한 대표 선율 검색을 제안한다. 대표 선율 검색을 위해 FFT(Fast Fourier Transform)을 이용하여 박자와 마디를 찾고 각 마디들의 PCM 데이타로부터 높은 수치가 나타나는 빈도를 측정한다. 이때 높은 수치들이 가장 많이 뭉쳐 있는 영역에서 여덟 마디 간격이 오디오 데이타의 대표 선율 영역이다. 제안 방법의 유효성을 검증하기 위한 실험으로 총 1000곡을 선택하여 대표 선율을 추출하였고, 그 결과 템포를 찾아낸 737곡 중 79.5%의 정확성을 보였다.

• 한국터널지하공간학회 논문집
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• 제18권2호
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• pp.235-244
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• 2016

해저터널 시공 중 단층, 파쇄대 및 미고결층 등의 취약한 지반조건에서 일어나는 문제점을 극복하기 위해 시공 중 그라우팅을 진행한다. 암반에서 그라우팅은 주로 불연속면을 따라 주입되므로 절리의 분포, 거칠기 또는 폭과 같은 절리 인자들이 그라우팅 보강암반의 물성에 지대한 영향을 미친다. 해저터널 주변의 그라우팅 보강암반은 해저환경에서 정수압을 다 부담하여 장기적인 열화와 미세구조변화 및 균열 등이 발생하며 암반물성이 시간에 따라 변하므로 그라우팅으로 인한 해저터널 주변암반의 장기적인 거동평가가 요구된다. 본 연구에서는 실내실험을 통해 다양한 축 응력, 양생기간 및 절리조건에서 그라우팅 보강암반의 탄성파 전달특성을 분석하였고 국내에서 사용되는 다양한 암반분류법들의 탄성파 기준을 고려하여 그라우팅 보강암반의 보강정도를 탄성파 속도로 추론하였다.

• 대한치과교정학회지
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• 제46권6호
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• pp.345-355
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• 2016

Objective: The purpose of this study was to determine whether predicting maturation of the midpalatal suture is possible by classifying its morphology on cone-beam computed tomography (CBCT) images and to investigate relationships with other developmental age indices. Methods: The morphology of the midpalatal suture was assessed by using CBCT images of 99 patients. Axial plane images of the midpalatal suture were classified into five stages according to the classification scheme. To make the assessment more accurate, the morphology and fusion of the midpalatal suture were additionally investigated on coronal cross-sectional planar images and volume-rendered images. Bone age was evaluated using the hand and wrist method (HWM) and cervical vertebrae method (CVM); dental age (Hellman's index), sex, and chronological age were also assessed. To evaluate relationships among variables, Spearman's rho rank test was performed along with crosstabs using contingency coefficients. Results: The HWM and CVM showed strong correlations with the maturation stage of the midpalatal suture, while other indices showed relatively weak correlations (p < 0.01). Through crosstabs, the HWM and CVM showed high association values with CBCT stage; the HWM demonstrated slightly higher values (p < 0.0001). Based on the HWM, the midpalatal suture was not fused until stage 6 in both sexes. Conclusions: Among developmental age indices, the HWM and CVM showed strong correlations and high associations, suggesting that they can be useful in assessing maturation of the midpalatal suture.

• 통상정보연구
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• 제19권2호
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• pp.25-44
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• 2017

국제무역에서 전자상거래가 차지하는 비중은 급속도로 증가하고 있지만, 가장 기본적인 개념정의와 적용규범에 대한 합의도 이루어지지 않은 상태이다. WTO에서는 '디지털 콘텐츠'에 잠재적 무관세를 시행하는 한편 작업계획(Work program)을 통해 전자상거래에 대한 폭넓은 연구를 진행하고 있으며, 각국은 FTA 등의 협정을 통해 자국의 이익을 추구하고 있다. 본 연구는 한국이 체결 시행하고 있는 FTA 중에서 전자상거래에 관한 규정을 비교 분석하였다. 한국의 FTA전자상거래 규정은 무관세, 다른 장(chapter)의 규정과 충돌 시 다른 장의 규정 우선, 전자인증, 개인정보보호, 소비자보호 등에 대해서는 공통적이지만, 전자상거래의 대상을 각기 다르게 정의하고 있고, 전자상거래의 분류 및 적용규범에 대해서는 유보하고 있으며, 비차별대우에 대해 다르게 규정하는 등 일관성이 부족하고 체계적이지 못한 상황이다. 한국은 WTO 등의 연구에 참여하고, 미국, EU, 중국 등이 체결 시행하고 있는 FTA전자상거래 규정을 분석하여 적극적 탄력적으로 대처할 필요가 있다.

• The Plant Pathology Journal
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• 제36권4호
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• pp.346-354
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• 2020

Pectobacterium, which causes soft rot disease, is divided into 18 species based on the current classification. A total of 225 Pectobacterium strains were isolated from 10 main cultivation regions of potato (Solanum tuberosum), napa cabbage (Brassica rapa subsp. pekinensis), and radish (Raphanus sativus) in South Korea; 202 isolates (90%) were from potato, 18 from napa cabbage, and five from radish. Strains were identified using the Biolog test and phylogenetic analysis. The pathogenicity and swimming motility were tested at four different temperatures. Pectolytic activity and plant cell-wall degrading enzyme (PCWDE) activity were evaluated for six species (P. carotovorum subsp. carotovorum, Pcc; P. odoriferum, Pod; P. brasiliense, Pbr; P. versatile, Pve; P. polaris, Ppo; P. parmentieri, Ppa). Pod, Pcc, Pbr, and Pve were the most prevalent species. Although P. atrosepticum is a widespread pathogen in other countries, it was not found here. This is the first report of Ppo, Ppa, and Pve in South Korea. Pectobacterium species showed stronger activity at 28℃ and 32℃ than at 24℃, and showed weak activity at 37℃. Pectolytic activity decreased with increasing temperature. Activity of pectate lyase was not significantly affected by temperature. Activity of protease, cellulase, and polygalacturonase decreased with increasing temperature. The inability of isolated Pectobacterium to soften host tissues at 37℃ may be a consequence of decreased motility and PCWDE activity. These data suggest that future increases in temperature as a result of climate change may affect the population dynamics of Pectobacterium.

• 한국음향학회지
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• 제19권8호
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• pp.78-83
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• 2000

수동 소나 시스템에서는 수중 소음원에 대한 신호처리 과정을 수행하여 토널 및 주파수선의 신호 성분으로부터 신호 세기 대역폭, 토널 개수, 토널간의 상호 관계둥의 다양한 특징인자를 분석, 비교하여 표적을 식별하게 되며, 표적 식별율을 향상시키기 위해서는 무엇보다도 주파수선의 신호 성분만을 정밀하게 탐지하고 추출하여야 한다. 그러나 수중신호의 스펙트로그램상에 형성되는 협대역 주파수선은 토널의 신호 세기와 바다 자체의 전달 특성 둥으로 인하여 미약하게 탐지되거나 불규칙하게 끊어져서 불연속적으로 나타날 뿐 아니라 임펄스성의 주변잡음 성분과 복합적으로 존재하므로 주파수선의 신호 성분만을 정밀하게 탐지하고 추출하기가 매우 어렵다. 본 논문에서는 신호 세기가 미약한 경우나 높은 주변잡음이 복합되어 있는 경우에도 정밀하게 주파수선의 신호 성분만을 탐지, 추출한 수 있는 협대역 다중 주파수선의 자동 탐지 및 추출을 위한 기법을 제안하였으며, 실제 수중표적 신호를 적용하여 제안된 알고리즘이 매우 유용함을 보인다.