• 한국산학기술학회논문지
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• 제19권1호
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• pp.654-659
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• 2018

본 연구에서는 연안 환경에 대한 대표적인 지상 원격 관측 기기인 Ocean Radar를 이용하여 장기파랑관측을 수행하였다. 지상에 설치한 기기로부터 이루어지는 원격 관측은 소수의 현장 기기 개수로는 관측할 수 없는 넓은 범위의 해역을 통시에 관측할 수 있고 또한 높은 빈도의 지속적인 관측이 가능한 장점이 있다. 장기관측을 위한 Ocean Radar는 과거 지진해일에 의한 피해가 발생하고, 원자력 발전소가 위치한 한국 동해안의 삼척지역에 대해 장기관측을 수행하였으며, 원격관측의 적용성을 검토하기 위해 수압식 파고계를 설치하여 각각의 조사자료를 비교하였다. 원격파랑관측은 연구대상해역 전면에 독일 Helzel사에서 개발된 Array type의 HF-RADAR인 WERA (WavE RAdar)를 2개소에 설치하여 자료를 취득하였으며, 장기간 연속된 관측된 자료의 취득률을 분석해본 결과, Ocean Radar 가 설치된 두 Site의 중심에서 약 24km이며, 약 27km의 범위 내에서는 Wave 자료가 90% 이상 취득되었으며, 시계열로 분석한 결과, 결측된 시간이 전체 계측기간의 1% 미만이다. 직접관측방식인 수압식 파고계와 관측자료를 비교한 결과, RMS 편차는 20cm 이내이며, 상관계수가 0.84 ~ 0.87로 높은 상관관계를 가지는 것으로 분석되었다. 따라서, 금회적용한 Ocean Radar는 기존의 파랑 계측 장비를 대체하여 장기간 면적 파랑관측이 가능할 것으로 생각된다.

• 대기
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• 제24권2호
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• pp.151-158
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• 2014

This study investigated a method for the discrimination of precipitation type using thickness of geopotential height at 1000~850 hPa and improved Matsuo's scheme over South Korea using 7 upper-level observations data during winter time from 2003 to 2008. With this research, it was suggested that thickness between snow and rain should range from 1281 to 1297 gpm at 1000~850 hPa. This threshold was suitable for determining precipitation type such as snow, sleet and rain and it was verified by investigation at 7 upper-level observation and 10 surface observation data for 3 years (2009~2011). In addition, precipitation types were separated properly by Matsuo's scheme and its improved one, which is a fuction of surface air temperature and relative humidity, when they lie in mixed sectors. Precipitation types in the mixed sector were subdivided into 5 sectors (rain, rain and snow, snow and rain, snow, and snow cover). We also present the decision table for monitoring and predicting precipitation types using model output of Korea Local Analysis and Prediction System (KLAPS) and observation data.

• Journal of Magnetics
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• 제3권2호
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• pp.39-40
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• 1998

Normal state EPR signals have been studied for the n-type$ high-T_c$ superconductors $Nd_{1.85}Ce_{0.15}CuO_{4-x} and Nd_2CuO_{3.6-x}F_{0.4-y}.$ Since EPR signals were observed only in quenched non-superconducting samples and were absent in furnace-cooled samples, our results suggest that no normal state EPR signals come from pure phase n-type hihg-Tc superconductors. Our observation is consistent with previously reported absence of nomal state EPR signals in the p-type high-Tc superconductors.

• 한국조경학회지
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• 제25권1호
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• pp.112-123
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• 1997

This study investigated the effect of high-rise buildings on the preference for rural landscapes. The study site was a Seoul suburban, Yong-in, which showed typical scenes of rural development. Slides used in the study were taken in Young-in along the national road 45(north-south) and national road 42(east-west). Forty slides reflecting typical characters of Young-in were selected. Among them, ten slides which were selected through factor analysis based on “ruralits”score were used as original slides. They represent ten landscape types. The simulation of original slides was based on the following aspects: a observation distance. number of buildings and landscape types. The preferences for the landscapes were tested by 200 respondents on 40 slides: Distance(2) ${\times}$ Landscape type(10) = 20 slides, Number of buildings(2) ${\times}$ Landscape type(10) = 20 slides. The following results are found: 1) When high-rise buildings are introduced into rural scenes, there are some vulnerable landscape types: the landscape with high “rurality”, the landscape with background skyline and the focal landscape. 2) The observation distance affects landscape preference. The hypothesis that the nearer the distance the lower the preferences, is accepted. However, there are some exceptions in 3 landscape types. 3) The hypothesis that the more the number of buildings, the lower the preferences, is rejected. The result is quite unexpected one. When a single building is introduced in natural scene, it draws more attention as a focal point than a group of buildings, and subsequently the visual impact is stronger.

• Restorative Dentistry and Endodontics
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• 제21권1호
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• pp.54-69
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• 1996

The purpose of this vitro study was to evaluate attachment and proliferation of human pulpal cells to the attachment glycoprotein-coated and non-coated culture dishes. Well known adhesive glycoproteins were used, such as type I collagen, type IV collagen, fibronectin, laminin, and vitronection. Each adhesive glycoproteins applied onto the culture dishes. In this study, the protein coated and non-coated dishes were classified as each groups. Human pulpal cells onto each culture dishes. After 90 minute, 4 hour and 24 hour incubation attached cells in each group were counted with hematocytometer for evaluation of the attachemnt of human pulpal cells. The configurations of attached human pulpal cells were done by SEM observation. The results as follows : 1. After 90 minute incubation the score of attachment of human pulpal cells was best in laminin-coated group among groups. Then fibronectin, type IV collagen group were better, and all proteins were higher than control. 2. After 4 hour incubation the numbers of attachment of human pulpal cells were most in fibronectin coated group. 3. After 24 hour incubation all of adhesive glycoproteins showed high and similar attachemtn effect to human pulpal cells. 4. In SEM observation, fibronectin and type IV collagen groups showed well spreaded human pulpal cells, then laminin group was moderately spreaded, and vitronectin group was mildly spreaded as well as control group.

• 교육시설 논문지
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• 제19권4호
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• pp.3-10
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• 2012

This study is carried out to understand spacial characteristics, actual condition and behavior of use about homebase managed in variation type. Observation about moving line of students and questionnaire were tried to satisfy this purpose. As a result, classroom used as variation type for long time stay and homebase outside the classroom for short time stay were paralled managed in most schools. Density of school furniture in homebase of observed schools was about 36-37%, occupying area of each student was about $0.3-0.6m^2$. It was relatively low with the results of 45-54% and $0.94-1.15m^2$ observed in Japan schools, respectively. By the analysis about behavior of use through cross section of observation, the difference of staying time and personnel exchange between the students was higher at the school having homebase composed with various corners more than the school used it only as a locker room.

• The Journal of Advanced Prosthodontics
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• 제12권1호
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• pp.38-48
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• 2020

PURPOSE. The objective of this literature review was to analyze the cumulative survival rates (CSRs) of rigid and non-rigid double-crown-retained removable dental prostheses. MATERIALS AND METHODS. Screening of the literature published from January 1995 to December 2019 was performed by using electronic data base (Pubmed) and manual search. The CSRs of rigid and non-rigid double crown removable dental prostheses were investigated. RESULTS. A total of 403 articles were reviewed and 56 relevant articles of them were selected. Subsequently, 25 articles were included for data extraction. These articles were classified according to rigid and non-rigid type double crowns and further subdivided into teeth, implants, and teeth-implant combination types. The CSRs of rigid type double crown ranged from 68.9% to 95.1% of 5 to 10 years in tooth abutments, 94.02% to 100% over a 3-year mean observation periods in implant abutments, and 81.8% to 97.6% in tooth-implant combination. Non-rigid type double crowns had various CSR ranges from 34% to 94% maximum during 10 years observation in teeth abutment. The CSRs of non-rigid type had over 98% in implant abutments, and ranged from 85% to 100% in tooth-implant combination. CONCLUSION. The CSRs of double crowns varies according to types. With accurate evaluation of the remaining teeth and plan of the strategic implant placement, it could be successful treatment alternatives for partially or completely edentulous patients.

• 한국환경과학회지
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• 제18권3호
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• pp.255-261
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• 2009

We need water equivalent unit data of snowfall for the purpose of forecast and hydrology related research area. This study developed new method of automatic recording snowfall as weight unit. The instrument designed for measuring weight of snowfall by stain-gauge loadcell. Field test of instrument carried out at Daegwallyeong Obs. Station from 22 Jan. to 22 Feb. 2007. During observation period there is 15.3 cm snow depth and 16.0 mm of accumulated water equivalent depth at Daegwallyeong Obs. Station on 13 to 14 Feb. 2007. But the instrument of this study recorded 22.1 mm of water equivalent depth. It is not easy to explain difference between Daegwallyeong and this study. Because this study is only one case of comparison of snow measurement and there is very little amount of snow observation research. The density of snowfall calculated from 0.09 to $0.15g/cm^3$ from the observation data of 13 to 14 Feb. 2007. There is high relation between radar echo and snowfall amount measured by weight unit. It can supports forecast of snowfall and development of numerical model for forecast.

• 한국동물학회지
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• 제37권1호
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• pp.49-57
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• 1994

In the course of an investigation on the morphological variation of Korean striped bittering, Acheilognathus vamatsutae Mori, two kinds of morrholoflical types were found. Some morphological characters were compared between them and multivariate analysis was conducted. Since the difference of the barbel length between them was very significant (p < 0.01,1-test), they should be designated as L-and 5-type Hshes: fishes with long barbels and those with should barbels, respectively. Lateral line scales, snout length and prepectoral length showed a tendency that the observation could be distinguished from each other (p < 0.05, Duncan's multiple range tests. There were no individuals over 70 mm BL in S-type and so S-type fishes were somewhat dwarf than L-type fishes. The two types were also clearly distinguished by multivariate analyses using cluster and discriminant analyses. According to the observation on the four populations of the Naktong River, the blue-green stripe on the body side and the white band on the margin of anal fin in males of S-type fishes were well developed through the year but those of males of L-type fishes completely disappeared or became slender during nonbreedins season as that of females. Of the seven localities surveved, there were no places that the two types cohabit. S-type fishes are limited only in the Kumho and Wichon River of the Naktong River system but L-type fishes are distributed more widely In the Hongchon, Mangvons, Somjin, Mirang and Panbyon River.

• 한국과학교육학회지
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• 제29권5호
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• pp.531-540
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• 2009

과학적 관찰은 과학 탐구 및 과학적 지식생성과정에 있어 기초적이며, 매우 중요한 과정으로써 인식되고 있다. 그러나 과학적 관찰의 중요성에 대한 인식에 비해 학습자에게 제시되어야 하는 과학적 관찰의 의미와 과정에 대한 연구는 미비한 실정이다. 과학적 관찰에 대한 대다수의 연구들은 관찰행동과 관찰사실의 특징과 유형을 알아보기 위한 것들로써 학습자에게 제공되는 관찰활동이 어떻게 구조화되어야 하는지에 대한 해답을 제시하는데 한계점을 지니고 있다. 이 연구에서는 이전의 체계적이고 다양한 연구결과들을 바탕으로 과학적 관찰의 의미와 과정에 대해 알아보았다. 과학적 관찰이란 대상으로부터 얻을 수 있는 감각 정보를 수용하여 관찰자의 주관적 요소로 구성된 지적틀을 통해 정보를 인식하는 활동이라고 할 수 있다. 또한, 관찰행동을 통해 인식된 정보는 관찰자의 주관적 요소에 해당하는 지적틀을 통해 관찰사실로 생성되어 추론과 독립적으로 지적틀에 영향을 미치거나, 추론에 의해 변환되어 지적틀에 영향을 주게 된다. 결국, 관찰자의 지적틀은 과학적 관찰에 의해 계속적으로 변화됨으로써, 이후에 수행되는 관찰행동과 관찰 사실 생성에 영향을 주는 것이라고 할 수 있다. 그러므로 과학적 관찰활동은 학습자의 주관적 요소가 고려되어야 하며, 추론과 연계된 관찰활동이 제시되어야 한다. 또한, 다양한 대상에 대한 관찰뿐만 아니라, 지속적 관찰활동을 통해 학습자의 지적틀이 변화될 수 있는 기회가 제공되어야 한다.