• Korean Journal of Remote Sensing
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• v.38 no.2
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• pp.179-188
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• 2022

Global warming causes climate change and increases extreme weather events worldwide, and the occurrence of heatwaves and droughts is also increasing in Korea. For the monitoring of extreme weather, various satellite data such as LST (Land Surface Temperature), TCI (Temperature Condition Index), NDVI (Normalized Difference Vegetation Index), VCI (Vegetation Condition Index), and VHI (Vegetation Health Index) have been used. VHI, the combination of TCI and VCI, represents the vegetation stress affected by meteorological factors like precipitation and temperature and is frequently used to assess droughts under climate change. TCI and VCI require historical reference values for the LST and NDVI for each date and location. So, it is complicated to produce the VHI from the recent satellite GK2A (Geostationary Korea Multi-Purpose Satellite-2A). This study examined the retrieval of VHI using GK2A AMI (Advanced Meteorological Imager) by referencing the historical data from VIIRS (Visible Infrared Imaging Radiometer Suite) NDVI and LST as a proxy data. We found a close relationship between GK2A and VIIRS data needed for the retrieval of VHI. We produced the TCI, VCI, and VHI for GK2A during 2020-2021 at intervals of 8 days and carried out the interpretations of recent extreme weather events in Korea. GK2A VHI could express the changes in vegetation stress in 2020 due to various extreme weather events such as heatwaves (in March and June) and low temperatures (in April and July), and heavy rainfall (in August), while NOAA (National Oceanic and Atmospheric Administration) VHI could not well represent such characteristics. The GK2A VHI presented in this study can be utilized to monitor the vegetation stress due to heatwaves and droughts if the historical reference values of LST and NDVI can be adjusted in a more statistically significant way in the future work.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.4
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• pp.22-33
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• 2006

The objective of this paper is to discuss geographic information policies and strategies of British government and suggest effective policies for Korea National GIS project GIS that has been implemented geographic information infrastructures into public sectors and private markets for the last ten years. To obtain the research aim, this paper reviews the main factors of the Britain GIS project such as distribution structure and process of GI markets, government policies and strategies that are led by Ordnance Survey, most leading mapping agency in the UK. In conclusion, some issues have been explored with reference to the experiences of the Britain GIS projects. The first of these is the nature of geographic information and the second concerns the notion of the circulation policies of spatial data, and the last proposes Korea GIS policies and strategies for successful geographic information and spatial data implementation. The findings of the analysis of the Britain GIS development indicate that a shift began to take place from central government coordinate toward more extensive utilization of private and commercial sectors. This reflects both the increasing importance of geospatial data circulation in all levels of GIS stakeholders. Finally these discussions are particularly to be the issues where multi-agency collaboration of Korea government is concerned and can take the form of joint ventures by consortiums of both involving data producers and data users in order to increase commercial participation for value-added geospatial items, and to encourage both research and development sectors with low or free price policies.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.4
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• pp.68-80
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• 2015

To increase the utilization of the KOrea Multi-Purpose SATellite(KOMPSAT) series imagery being developed pursuant to the national space development program, high quality images with enhanced locational accuracy should be created through standardized post-processing processes. In the present study, using the Value-Added Processing System(VAPS) constructed for the post-processing of KOMPSAT imagery, location correction experiments were conducted using KOMPSAT-2 and -3 imagery from domestic and overseas regions. First, 50 pieces from each of KOMPSAT-2 imagery were selected from South Korean and North Korean regions, and modeling was conducted using GCP Chips. According to the results, the Root Mean Square Errors(RMSE) for South Korea and North Korea were 1.59 pixels and 2.04 pixels, respectively, and the locational accuracy of ortho mosaic imagery using check points were 1.33m(RMSE) and 1.90m(RMSE), respectively. Meanwhile, in the case of overseas regions for which GCP could not be easily obtained, the improvement of locational accuracy could be identified through image corrections using Open Street Map(OSM). The VAPS and reference materials used in the present study are expected to be very useful in constructing a precise image DB for entire global regions.

• Korean Journal of Remote Sensing
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• v.32 no.4
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• pp.365-382
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• 2016

The results from the Global Positioning System (GPS) measurements of the Mobile Observation Vehicle (MOVE) on the eastern coast of Korea have been compared with REFerence (REF) values from the fixed GPS sites to assess the performance of Precipitable Water Vapor (PWV) retrievals in a kinematic environment. MOVE-PWV retrievals had comparatively similar trends and fairly good agreements with REF-PWV with a Root-Mean-Square Error (RMSE) of 7.4 mm and $R^2$ of 0.61, indicating statistical significance with a p-value of 0.01. PWV retrievals from the June cases showed better agreement than those of the other month cases, with a mean bias of 2.1 mm and RMSE of 3.8 mm. We further investigated the relationships of the determinant factors of GPS signals with the PWV retrievals for detailed error analysis. As a result, both MultiPath (MP) errors of L1 and L2 pseudo-range had the best indices for the June cases, 0.75-0.99 m. We also found that both Position Dilution Of Precision (PDOP) and Signal to Noise Ratio (SNR) values in the June cases were better than those in other cases. That is, the analytical results of the key factors such as MP errors, PDOP, and SNR that can affect GPS signals should be considered for obtaining more stable performance. The data of MOVE can be used to provide water vapor information with high spatial and temporal resolutions in the case of dramatic changes of severe weather such as those frequently occurring in the Korean Peninsula.

• Journal of the Korea Convergence Society
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• v.7 no.1
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• pp.89-95
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• 2016

The purpose of this experiment intend to evaluate the quality of the image based on the orbit and basal ganglia with high radiosensitivity for the noise, SNR and dose using the five kinds patient fixing pad in brain phantom MDCT(BrillianceTM CT 64 slice, PHILIPS, Netherward). The noise had a higher values in AP than those of others, but the SNR was lower in AP than those of others. The SNR was higher in UP than those of RP, PP, SP and AP. The UP, RP and PP were no statistically significant(p>0.05), whereas it was significant difference between UP, RP, PP and SP, AP(p<0.05). This is causes of the noise difference is generated due to the differences in the radiation absorption dose in accordance with each the component of the absorbed dose level of the detector according to the reference line and each of SOML when the radiation exposured. The CTDIvol(mGy) and DLP of orbit and basal ganglia were 56.95, 911.50, respectively. There is no difference between both mean dose. In conclusion, it is possible to distinguish among a kind of 5 patient fixing pad by using brain phantom MDCT. Overall, patient fixing pad of UP, RP and PP based on a brain phantom MDCT can provide useful information.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.2 no.1
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• pp.236-265
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• 1974

The study is to trace the origin of the Hongmunkwan ana discuss its development and roles assigned in each succeeding stages of the history. The Hongmunkwan lived a long life through Koryo and Yi dynasties. It was a multi-functioned institution designed as a royal library, an educational institution, and a political reference center. Prior to the Hongmunkwan, there were some established institution with similar functions to its ones during the Three-Kingdom Era. One of such kind was the Sungmunkwan(崇文館), which was eventually renamed the Hongmunkwan by King Songjong(成宗) of Koryo in 995, and a distinguished scholar-minister was appointed at the position of directorship for management of the now status-raised institution where state documents and books were housed. The Hongmunkwan experienced some reforms during its long life. In 1420, King Sejong(世宗) of Yi Dynasty founded the Jipyonjon(集賢殿) within the royal palace in place of the Hongmunkwan. The Jipyonjon was an innovated Hongmunkwan where many scriptures were stored and distinguished scholars and officials studied on them, sometimes delivering lectures to the king. King Sejo(世祖) abolished the Jipyonjon in his second year(1456) and reestablished the Hongmunkwan designed as a royal library in place of the former in his ninth year. King Songjong(成宗) in his 10th year (1479) of the reign, reformed the Yemunkwan(藝文館), which existed from the beginning of the Yi dynasty, by extending its functions and afterwards absorbed it into the Hongmunkwan together with the functions of the former Jibhyonjon which were included in the Yemunkwan. He founded another Yemunkwan which had the roles of drafings and descriptions of royal decrees. In the 10th year (1504) of Yonsankun(燕山君), the Hongmunkwan was abolished and instead of it the Jindokchong(進讀廳) was founded with less authority and functions. But shortly after that, King Jungjong(中宗) refounded the Hongmunkwan with the same scale, same authority and same functions as the former, one. As the Hongmunkwan also had a function of the royal library it collected and kept numerous books and writings in it. Some books and writings of the Hongmunkwan were composed of those which had been transmitted from the Koryo Dynasty and the others were composed of those which had been collected in the country or purchased by the trade with China in the Yi dynasty. Also newly-compiled important books in the country were reprinted and one of them were send to the Hongmunkwan. In the 8th year (1784) of King Jongjo(正祖), the history of the Hongmunkwan, entitled the Hongmunkwanji(弘文館志), was written and editioned by the royal decree and it was reeditioned the 7th year (1870) of King Kojong(高宗). The Hongmunkwan was absorbed into the Kyujanggak(奎章閣) in 1907.

• Korean Journal of Health Education and Promotion
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• v.22 no.2
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• pp.19-32
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• 2005

Objectives: The purpose of this study was to examine teachers' safety education activities to determine the significant educational diagnosis variables and to identify their needs of safety education in early-child care centers based on the PRECEDE model. Methods: A total of 304 teachers in early-child care centers participated in this study selected by a multi-stage stratified sampling method considering 11 regions in Seoul, Korea. Self-report type questionnaires were posted to all teachers in 220 early-child care centers by ground mailing service and the 304 teachers completed the questionnaires. The participants' responses were anonymously coded into and analyzed in SPSS program. Results: 'Scratch or bite' was the most frequent accident type(78.3%) and the frequent accident places were 'classroom(88.8%)' and 'playground(67.8%)'. The most frequently conducted safety education activities were 'reminding children their safe behaviors at the beginning and the end of daily class' and the next was 'saving a special time for safety education.' For educational diagnosis factors, related to safety education activities, teachers' safety education activity was more frequent when teachers' safety knowledge was high(p<.001), when teachers had good application skills of their knowledge to their teaching activities(p<.001), when they had strong needs on safety training opportunities(p<.05), and their interests on safety education(p<.001). For enabling factors, class preparation by safety education guide-book review(p<.001), by development of educational materials(p<.001), and by search for the related reference (p<.001), and by participation to safety education training programs for teachers(p<.01) were the significant enabling factors on teachers' safety class activities. For the reinforcing factors, the center-wide support of safety education brochures to children (p<.001), the concerns of centers utilizing safety education specialists(p<.001), and the concerns about safety information collection out of centers(p<.001) were significant factors related with teachers' safety education activities. Conclusions: The significant educational and institutional factors on teachers' safety education activities were teachers' concerns on safety education, their interests on safety knowledge, and the strong concerns on child safety education from the centers.

• Korean Journal of Biological Psychiatry
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• v.12 no.2
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• pp.123-135
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• 2005

Objectives:EEG coherence could imply the connectivity between two different areas of the brain, which is known to be important in the pathophysiology of bipolar I disorder(BPD I) and schizophrenia. The authors investigated EEG coherence in patients with BPD I and schizophrenia to examine the connectivity of the neural circuit. Methods:EEGs were recorded in 15 schizophrenia and 14 bipolar disorder patients, and 14 age-matched normal control subjects from 16 electrodes with linked-ear reference. Spectral parameters and coherence were calculated for the alpha bandwidth(8-13Hz) by a multi-channel autoregressive model using 20 artifact-free 2-seconds epochs and the differences were compared among three groups by two different statistical methods;F-test and Kruskal-Wallis test. Furthermore, when there were significant differences among three groups, Scheffe's multiple comparison tests were provided and Jonckheere-Terpstra tests for the ordered alternative were given. Results:In the intra-hemispheric comparison, left frontal coherence was increased in order of control, BPD I and schizophrenia. In the inter-hemispheric comparison, 1) inter-prefrontal coherence in BPD I was signifi- cantly higher than in normal controls, and 2) inter-prefrontal coherence in schizophrenia was significantly lower than in controls. Conclusion:These results suggest that 1) both schizophrenia and BPD I are diseases having the abnormality of neural circuit connectivity in both frontal and prefrontal lobes, and 2) the abnormality is more severe in schizophrenia than in BPD I. Furthermore, the data support that a common pathogenetic process may reside in both schizophrenia and BPD I.

• Korean journal of food and cookery science
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• v.25 no.2
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• pp.252-259
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• 2009

Ergosterol is the significant component of the cell wall of fungi. Its presence is regarded as evidence of fungi contamination in grain and other foods. Many studies on ergosterol detection have been carried out using chemical methods, but those methods required complicated pre-treatments and long analysis times. In this study, an amperometric biosensor was developed for fast and precise ergosterol detection. The biosensor system used the electron transfer of hydrogen peroxide produced from the reaction of ergosterol with cholesterol oxidase. The biosensor system consisted of a peristaltic pump, a syringe loading sample injector, an enzyme reactor, a fabricated flow-through cell containing a working electrode, a reference electrode and a counter electrode, and a potentiostat/recorder. The working electrode was prepared by coating modified multi-wall carbon nanotube (MWNT) on glassy carbon electrode. The $MWNT-NH_2$ coated glassy carbon electrode linearly responded to hydrogen peroxide in the range of $1{\times}10^{-5}{\sim}8{\times}10^{-5}$ M with a detection limit of $10^{-7}$ M in the basic performance test. The currents produced from the ergosterol biosensor showed the linearity in a range from $1.0{\times}10^{-6}$ M to $1.0{\times}10^{-5}$ M ergosterol.

• Journal of radiological science and technology
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• v.40 no.2
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• pp.229-235
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• 2017

In abdominal Ultrasonography, the fatty liver is diagnosed through hepatic parenchymal echo increased parenchymal density and unclear blood vessel boundary, and according to many studies, abdominal Ultrasonography has 60~90% of sensitivity and 84~95% of specificity in diagnosis of fatty liver, but the result of Ultrasonography is dependent on operators, so there can be difference among operators, and quantitative measurement of fatty infiltration is impossible. Among examinees who same day received abdominal Ultrasonography and chest computed tomography (CT), patients who were diagnosed with a fatty liver in the Ultrasonography were measured with liver Hounsfield Units (HU) of chest CT imaging to analyze the accuracy of the fatty liver diagnosis. Among 720 subject examinees, those who were diagnosed with a fatty liver through abdominal Ultrasonography by family physicians were 448, which is 62.2%. The result of Liver HU measurement in the chest CT imaging of those who were diagnosed with a fatty liver showed that 175 out of 720 had the measured value of less than 40 HU, which is 24.3%, and 173 were included to the 175 among 448 who were diagnosed through Ultrasonography, so 98.9% corresponded. This indicates that the operators' subjective ability has a great impact on diagnosis of lesion in Ultrasonography diagnosis of a fatty liver, and that in check up chest CT, under 40 HU in the measurement of Liver HU can be used for reference materials in diagnosis of a fatty liver.