• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.654-659
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• 2018

In this study, continuous long-term observation is implemented with an ocean radar. Ocean radar conducts remote observation (combined) with ground-based radars, which enable a series of simultaneous observations of an extensive range of the coast with high frequency. An ocean radar for continuous long-term observation is operated at Samcheok on the east coast of Korea. Samcheok experienced tsunami damage in recent years and is the location of a nuclear power plant. In order to examine the reliability of the ocean radar, a pressure-type wave gauge, ultrasonic wave gauge, and ocean buoy are installed for the purpose of data comparison and verification. The ocean radar used in this study is an array-type HF-RADAR named WERA (WavE RAdar). The analysis of the data obtained from continuous long-term observations showed that the radar observations were in agreement with more than 90% of the wave data collected within a 25 km range from the center of two sites. Less than 1% of the entire observation data was unmeasured by the time series analysis. As a result of comparing the radar data with the direct observations made by the wave gauge, it was inferred that the RMS deviation is less than 20cm and the correlation coefficient was in the range of 0.84 ~ 0.87. Moreover, supported by such observations, a comprehensive monitoring system is being developed to provide the public with real-time reports on waves and currents via the internet.

• Atmosphere
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• v.24 no.2
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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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• v.3 no.2
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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.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.1
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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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• v.21 no.1
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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.

• Journal of the Korean Institute of Educational Facilities
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• v.19 no.4
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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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• v.12 no.1
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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.

• Journal of Environmental Science International
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• v.18 no.3
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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.

• The Korean Journal of Zoology
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• v.37 no.1
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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.

• Journal of The Korean Association For Science Education
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• v.29 no.5
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• pp.531-540
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• 2009

The purpose of this study is to investigate the meaning and process of scientific observation. Hence, this study reviewed and discussed meanings and process of scientific observation described in philosophy, the philosophy of science and science education. Major researches on scientific observation are focused on a characteristic and type of scientific observation behavior. These research can suggest what is the characteristic of observation facts generated by observer. But it cannot show what is the meaning and process of scientific observation, it should be provide to students. According to the result in this study, scientific observation is affected by observer's subjective factors, such as experience, background knowledge, interpretation(not inference) and observation skill. All factor are integrated as an intellectual framework, and it is able to be changed by the observed facts. On the other hand, inference is excluded on scientific observation, but it have constantly affect on intellectual framework through feedback. This study on scientific observation provides a scaffold in various activities of scientific observation to be provided to students.