• Journal of the Korean Institute of Gas
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• v.21 no.6
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• pp.23-29
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• 2017

Solar and wind energy among the renewable energy produce irregular power because resource is difficult to control. When connected to grid have unstable. However, when the fuel cell system is connected to grid more stable because regular frequency and output power based on controllable hydrogen energy. To using fuel cell system in the household, it is important that the safety performance of power conditioning system(PCS) and it is important that evaluation method of electromagnetic compatibility(EMC). In this study, we consider that introduce power-frequency magnetic field immunity test before analyzed that compare with the EMC of the international standards and KGS AB 934 PC53. Also, we conduct that actual assessment and study on available the quantitative analysis as using complementary indicator.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.5
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• pp.1435-1443
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• 2016

This study evaluated the sanitary state of seawater and shellfish in Yeoja bay from January 2014 to June 2016. The sampling stations for sanitary survey in Yeoja Bay was composed of 50 stations for seawater and 4 stations for ark shell and the samples have been collected monthly at a stated date. The total and fecal coliforms in seawater and Escherichia coli (E. coli) in shellfish were investigated as sanitary indicator bacteria, respectively. The geometric mean and the estimated 90th percentile ranges of total and fecal coliforms for seawater were <1.8-3.9, <1.8-2.6 and <1.8-29.7, <1.8-9.3 MPN/100 mL, respectively. The range of E. coli levels for ark shell were <20~330 MPN/100 g. The sanitary state in Yeoja bay was evaluated clean area according Korea criteria and conditionally approved area according US criteria and Class B area according EU criteria.

• Korean Journal of Plant Resources
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• v.30 no.4
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• pp.435-449
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• 2017

A floristic study on the vascular plants from Mt. Seounsan region, which ranges from Seoun-myeon, Anseong-si, Gyeonggi-do to Baekgok-myeon, Jincheon-gun, Chungcheongbuk-do, was conducted 9 times in total, from April 2014 to October 2015. Based on the voucher specimens, it was revealed that the vascular plants in this region comprised 501 taxa: 97 families, 306 genera, 439 species, 5 subspecies, 51 varieties, and 6 forma. Among these plants, 185 taxa were recorded for the first time from this region. 8 Korean endemic species including Asarum patens (K.Yamaki) B.U.Oh, Scutellaria insignis Nakai, and Weigela subsessilis (Nakai) L.H.Bailey were found in this region. 5 taxa of rare plants designated by the Korea Forest Service, including Iris ruthenica KerGawl., Leontopodium leontopodioides (Willd.) Beauverd, and Tricyrtis macropoda Miq., were also found. 11 taxa of floristic regional indicator plants in the $3^{rd}$ to the $5^{th}$ degrees were identified. In addition, 46 taxa of naturalized plants were recorded, and 2 taxa of ecosystem disturbance plants, which were Ambrosia trifida L. and Aster pilosus Willd., also found.

• Journal of Korea Water Resources Association
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• v.51 no.10
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• pp.875-886
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• 2018

This study evaluated drought severity by bivariate frequency analysis using drought magnitude and precipitation deficit. A drought event was defined by Standardized Precipitation Index (SPI) and the precipitation deficit was estimated using reference precipitation corresponding to the SPI -1. In previous studies, drought magnitude and duration were used for bivariate frequency analysis. However, since these two variables have a largely linear relationship, extensibility of drought information is not great compared to the univariate frequency analysis for each variable. In the case of drought in 2015, return periods of 'drought magnitude-precipitation deficit' in the Seoul, Yangpyeong, and Chungju indicated severe drought over 300 years. However, the result of 'drought magnitude-duration' showed a significant difference by evaluating the return period of about 10, 50, and 50 years. Although a drought including the rainy season was seriously lacking in precipitation, drought magnitude did not adequately represent the severity of the absolute lack of precipitation. This showed that there is a limit to expressing the actual severity of drought. The results of frequency analysis for 'drought magnitude-precipitation deficit' include the absolute deficit of precipitation information, so which could consider being a useful indicator to cope with drought.

• Journal of Korea Water Resources Association
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• v.39 no.1 s.162
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• pp.59-68
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• 2006

To assess the water resources sustainability, many indicators and methodologies have been suggested by international organizations and developed in other countries. However, in the previous studies, some of indicators were unsuitable for assessing the sustainability of water use and management in Korea. Thus, in this study nSl(Water Resources Sustainability Index), a multi-variable index, was created by consideration of environmental, social, and economical criteria. Relative weights for components, indicators and sub-indexes, were determined by employing the Analytic Hierarchy Process. In order to extract the indicators related with water resources sustainability, the data related with water resources and indicators suggested in various field were compared and thoroughly reviewed. These indicators were classified into four groups; Economic Efficiency Index, Social Equity Index, Environmental Conservation Index, and Maintenance Capability Index. The weight of each component were decided by the survey of 127 specialists in water resources and sustainability. The result of survey represented that efficiency and equity of water use and water quality for river restoration are major issues in enhancing the water resources sustainability In addition, it was found that investment and public participation should be considered for sustainable water use.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.367-380
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• 2013

In this study, sub-indicators, and thematic mid-indexes to evaluate the water use characteristics were selected through historical data analysis and factor analysis, and consisted of the subject approach framework. And the integrated index was developed to evaluate water use characteristics of the watershed. Using developed index, the water use characteristics were assessed for 812 standard basins with the exception for North Korea using data of 1990 to 2007 from the relevant agencies. A sensitivity analysis is conducted for this study to determine the proper way through various normalization and weighting methods. To increase the objectivity of developed index, the history of the damage indicators are excluded in the analysis. In addition, in order to ensure its reliability, results from index with and without consideration of the damage history were compared. Also, the index is also applied to real data for 2008 Gangwon region to verify its field applicability. Through the validation process this index confirmed the adequacy for the indicators selection and calculation method. The results of this study were analyzed based on the spatial and time vulnerability of the basin's water use, which can be applied to various parts such as priority decision-making for water business or policy, mitigations for the vulnerable components of the basin, and supporting measures to establishment by providing relevant information about it.

• Korean Journal of Remote Sensing
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• v.35 no.5_1
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• pp.637-647
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• 2019

The detection of crop stress is an important issue for the accurate assessment of yield decline. The photochemical reflectance index (PRI) was developed as a remotely sensed indicator of light use efficiency (LUE). The PRI has been tested in crop stress detection and a number of studies demonstrated the feasibility of using it. However, only few studies have focused on the use of PRI from remote sensing imagery. The monitoring of PRI using drone and satellite is made difficult by the low spectral resolution image captures. In order to estimate PRI from multispectral sensor, we propose a band fusion method using adjacent bands. The method is applied to the drone-based hyperspectral and multispectral imagery and estimated PRI explain 79% of the original PRI. And time series analyses showed that two PRI data (drone-based and SRS sensor) had very similar temporal variations. From these results, PRI from multispectral imagery using band fusion can be used as a new method for evaluation of crop stress.

• The Korean Journal of Archival Studies
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• no.14
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• pp.53-89
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• 2006

The historical value of the official documents of the Government General of Choson preserved as permanent archived documents has long been recognized. However, the fact that only parts of the overall documents were preserved and that the contents of the existing documents is not uniform, results in many problems regarding the evaluation and usage of such documents as archives. This study attempts to appraise a series of archival documents related to urban district planning compiled during the colonial era. Although limited in terms of its applicability to the development of an evaluation method for the official documents of the Government General of Choson as a whole, by evaluating the value of these documents based on the background of the documents produced during the Government General of Choson's implementation of its colonial policy, this study provides an important indicator of how such documents should be used in the future. On the other hand, the assessment of historical records such as the official documents of the Government General of Choson which have already been designated and preserved as permanent archived documents should not be perceived as an attempt to dispose of the relevant documents. With regard to the appraisal of historical archives, it is necessary to consider measures to link such documents with existing databases or information contents in order to heighten access to and usage of the relevant documents in the future.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.93-105
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• 2019

This study want to identify problems related to mobile in-app payment from the perspective of consumers and suggest ways to solve them. Three scenarios have been developed to achieve the objectives of this study. This suggests the situation of in-app payment problem that consumers often experience. Then 323 consumers in their 20s and 30s read the scenario, identified the problem in each situation and assessed who was responsible. Consumers were aware of in-app payment problems due to problems with in-app payment readability, problems with app market responsibility, problems with responsibility of game companies, and problems of consumer responsibility. And different consumers had different levels of assessment on the problem of in-app payment. According to the research, consumers have high demand for improvement of the lack of readability in related laws, including strengthening the readability of the in-app payment indicator. In addition, the company confirmed the importance of cooperative efforts by consumers, businesses, and the government due to high consumer expectations for the role of the distribution company App Market other than the content developer game company.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.451-458
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• 2019

Reliability in the course of weapons system development and operation is a key measure of the ability of a system to perform the required functions under specified conditions over a specified period of time, and the mission confidence for the assessment of mission fulfillment is an important indicator of victory or defeat in a battle. Mission reliability indicates the probability that a given task will succeed or fail in an event or environmental situation over a given period of time. The existing mission reliability was calculated after creating a confidence blow map with only physical connections based on the mission. However, as modern weapons systems evolve and advance, the related equipment structure becomes increasingly complex, making it impossible to express mission relevance when mission classification is required based on functional or physical connections. In this study, the mission reliability was calculated for a gun control system, which is part of a ship's combat system, by expressing the association between the physical and functional structures using the design structure matrix technique and the interface matrix technique. We expect the study results to be used as verification data for mission reliability.