• The Korean Journal of Applied Statistics
• /
• v.17 no.3
• /
• pp.535-545
• /
• 2004

The clustering method suggested in this paper produces clusters based on the 'rules of variables' by merging the 'training' and the identically structured reference data and then by filtering it to obtain the clusters of the 'training data' through the use of the 'tree classification model'. The reference dataset is generated by spatially contrasting it to the 'training data' through the 'reverse arcing' algorithm to effectively identify the clusters. The strength of this method is that it can be applied even to the mixture of continuous and discrete types of 'training data' and the performance of this algorithm is illustrated by applying it to the simulated data as well as to the actual data.

• Journal of Korean Library and Information Science Society
• /
• v.31 no.4
• /
• pp.285-312
• /
• 2000

본 연구는 교회도서관규정에 관한 이론적인 배경을 확립하고, 교회도서관규정안을 제시하고자 한 것이다. 이론적 배경 항목으로 교회도서관의 기능, 조직, 직원, 자료, 열람봉사, 자료보존관리, 예산 및 전산을 채택하여 고찰하였다. 이러한 이론적인 배경 및 현행 3개 교회도서관규정을 비교 분석하여 교회도서관규정을 제시하였다. 본 연구에서 제시한 교회도서관규정안을 9장 30조로 구성되었으며, 내용은 (1)총칙, (2)조직, (3)도서관자문위원회, (4)운영, (5)수서, (6)열람 및 대출 (7)변상 및 제재, (8)자료의 제적, (9)자료의 복사 그리고 부칙으로 구성하였다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.6 no.4
• /
• pp.257-263
• /
• 2008

We analyzed the statistical properties for the conductive background fractures in the Low and Intermediate Level Waste(LILW) disposal site to conceptualize of its groundwater flow system. The background fractures were classified to fracture sets based on their trends and plunges that were obtained from the borehole logging data, and then the fracture transmissivity distribution was inferred from the fixed interval hydraulic test results. The fracture size distribution of each fracture set was estimated using the fracture density and fracture mapping data. To verify the analyzed results, we compared observed field data to simulated one from the DFN model that was constructed with the analyzed statistical properties of the background fractures, and they showed a good agreement.

• Korean Educational Research Journal
• /
• v.43 no.1
• /
• pp.89-123
• /
• 2022

This research aimed to explore the nature of teachers' experiences of multicultural education in primary schools with ethnic diversity in the Republic of Korea and draw policy implications. For this study, the researchers interviewed 15 primary school teachers using semi-structured questionnaires in mine different schools. The participating teachers were in charge of the multicultural education in schools with ethnic diversity in two rural counties in the Republic of Korea. The analysis of the empirical data suggests that teachers stationed in ethnic diversity have not been trained for the diverse population nor multicultural education in general. In addition, they were struggling with the lack of teaching resources including textbooks for multicultural education, support for students and their parents in need of learning Korean as a foreign language, accurate data of those students etc. These teacher policy implications are suggested while discussing the findings; such as the importance of practical in-service training opportunities, quality teaching resources, Korean as Second Language(KSL) experts, and accurate data of students with ethnic diversity.

• Geophysics and Geophysical Exploration
• /
• v.20 no.4
• /
• pp.199-206
• /
• 2017

Field data obtained from marine exploration are influenced by various environmental factors such as wind, waves, tidal current and flow velocity of a background medium. Most environmental factors except for the flow velocity are properly corrected in the data processing stage. In this study, the wave equation modeling considering flow velocity is used to generate observation data, and numerical experiments using the observation data were conducted to analyze the effect of flow velocity on waveform inversion. The numerical examples include the results with unrealistic flow velocities. In addition, an algorithm is suggested to numerically extract flow velocity for waveform inversion. The proposed algorithm was applied to the modified Marmousi2 model to obtain the results depending on the flow velocity. The effect of flow velocity on updated physical properties was verified by comparing the inversion results without considering flow velocity and those obtained from the proposed algorithm.

• Korean Journal of Remote Sensing
• /
• v.31 no.6
• /
• pp.583-598
• /
• 2015

This paper presents derivation of background temperature from geostationary satellite and its validation based on ground measurements and Geographic Information System (GIS) for future use in weather and surface heat variability. This study only focuses on daily and monthly brightness temperature in 2012. From the analysis of COMS Meteorological Data Processing System (CMDPS) data, we have found an error in cloud distribution of model, which used as a background temperature field, and in examining the spatial homogeneity. Excessive cloudy pixels were reconstructed by statistical reanalysis based on consistency of temperature measurement. The derived Brightness temperature has correlation of 0.95, bias of 0.66 K and RMSE of 4.88 K with ground station measurements. The relation between brightness temperature and both elevation and vegetated land cover were highly anti-correlated during warm season and daytime, but marginally correlated during cold season and nighttime. This result suggests that time varying emissivity data is required to derive land surface temperature.

• Journal of the Korean earth science society
• /
• v.42 no.2
• /
• pp.195-200
• /
• 2021

Orientation corrections for the total of 268 accelerograph stations of the Korea Meteorological Administration (KMA) were estimated using ambient noise cross-correlation. As this method uses ambient noise data instead of teleseismic waveforms from earthquakes under certain conditions, reliable orientation corrections can be obtained using only two-month long continuous seismic data from dense seismic networks in the Korean peninsula.Three-component continuous data recorded at the 268 accelerograph stations from January to February 2020 were used to estimate orientation corrections. The results are comparable to the previous results obtained from teleseismic waveforms; the overall standard deviations of the orientation corrections are less than 5°. Therefore, orientation corrections for the accelerograph station network can be tracked periodically by the ambient-noise method and the result can be used in various studies using the horizontal-component of acceleration data.

• Journal of Korean Society for Geospatial Information Science
• /
• v.3 no.1 s.5
• /
• pp.115-121
• /
• 1995

Recently, spatial integration for mineral exploration is regarded as an important task of various geological applications of GIS. Therefore, theoretical bases of data representation and reasoning concerned with Dempster-Shafer theory and Fuzzy theory were systematically as the data-driven integration methodologies for raster-based geoinformation; they are distinguished from target-driven methodology based on statistical background. According to previous actual applications of these methods to mineral exploration, they have been proven to provide useful information related to hidden target mineral deposits, and it is thought that some suggestions in this study are helpful to further real applications including representation, reasoning, and interpretation stages in order to obtain a decision-supporting layer.

• Journal for History of Mathematics
• /
• v.20 no.1
• /
• pp.57-72
• /
• 2007

Recently, dissection puzzles such as pentominoes have been used in mathematics education. But they are not actively applicable as a tool of problem solving or introducing mathematical concepts since researches about the historical background and developments of mathematical applications of such puzzles have not been effectively accomplished. In this article, in order to use pentominoes in mathematical teaming effectively, we first investigate geometric problems related to dissection puzzles and the historic background of development of pentominoes. And then we collect and classify data related to pentomino activities which can be applicable to mathematics classes based on the 7th elementary school national curriculum. Finally, we suggest several basic materials and directions to develop more systematic learning materials about pentominoes.

• Geophysics and Geophysical Exploration
• /
• v.16 no.4
• /
• pp.203-210
• /
• 2013

To look into site characteristics of the Hwacheon borehole seismic station, we analyzed property of earthquake and microtremor recorded on surface and borehole seismometers. Acoording to analysis result of microtremor, the surface-to-borehole energy ratio was approximately 15 times greater during the daytime than during the nighttime, and the surface-to-borehole ratios of spectral amplitudes as frequency increases. For earthquake data, amplitude spectra and dominant frequency were computed using surface and borehole data. As a result, small earthquakes with short distance recorded on surface seismometer peaked at 8 Hz, 46 Hz. This result corresponds to resonance frequencies (7.4 Hz, 46 Hz) calculated by H/V spectral ratio. We confirmed amplification effect by site characteristics of overburden. Background noise level was approximately 20,000 times smaller at borehole seismic station than surface seismic station. These results provide strong evidence for the superior recording of earthquakes using borehole seismometers instead of surface seismometers.