• Analytical Science and Technology
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• v.13 no.6
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• pp.693-698
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• 2000

The object of this series of experiments was aimed for the systematic and long-term radioactivity monitoring through indirect search of C-14 concentration level changes in the natural conditions around the operating nuclear facilities. The result of environmental radioactivity level through tree-ring analysis is increased after operating nuclear facilities and such a level can be proved to relate power generation closely. The measured result of ${\delta}^{13}C$ through the treatment of cellulose can be showed the level -30‰. This figure is very different from one which is measured the -17‰ of air sample by passive air sampling and -8‰ of air sample by active air sampling. And these differences can be assumed as isotope fractionation by photosynthesis, but the problem is more study as needed.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.154-163
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• 2018

Not only South Korea but also Global world show that the frequency and damages of large-scale natural disaster due to the rise of heavy rain event and typhoon or hurricane intensity are increasing. Natural disasters such as typhoon, flood, heavy rain, strong wind, wind wave, tidal wave, tide, heavy snow, drought, earthquake, yellow dust and so on, are difficult to estimate the scale of damage and spot. Also, there are many difficulties to take action because natural disasters don't appear precursor phenomena However, if scale of damage can be estimated, damages would be mitigated through the initial damage action. In the present study, therefore, wind wave damage estimation functions for the western coastal zone are developed based on annual disaster reports which were published by the Ministry of Public Safety and Security. The wind wave damage estimation functions were distinguished by regional groups and facilities and NRMSE (Normalized Root Mean Square Error) was analyzed from 1.94% to 26.07%. The damage could be mitigated if scale of damage can be estimated through developed functions and the proper response is taken.

• Korean Journal of Ichthyology
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• v.28 no.4
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• pp.267-272
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• 2016

The feeding habits of Chaenogobius annularis were studied based on gut contents analysis of 315 individuals, collected from September 2014 to August 2015 in the tidepools at the intertidal zone of Tongyeong, Korea. The size of C. annularis ranged from 17.0 to 54.0 mm in standard length (SL). C. annularis mainly consumed copepods (especially Tigriopus japonicus). Its diets included seaweeds, cirripeds, mysids and amphipods. C. annularis showed ontogenetic changes in feeding habits. Small individuals fed mainly on copepods. As body size increased, the portion of seaweed increased, whereas the consumption of copepods decreased.

• Journal of Korean Institute of Industrial Engineers
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• v.40 no.1
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• pp.60-83
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• 2014

This paper aims to propose a research framework of analyzing voting activities of a national assembly on the basis of member-level voting similarity and provides a case study in the $18^{th}$ national assembly in South Korea. First, we propose a bill contentiousness measure that gives a higher score to bills for which ayes and noes are more diversified in both conservative and progressive parties. Based on the bill contentiousness measure, the top 5%, 10%, and 20% bills were identified and used for further analyses. Moreover, we propose a member-level voting similarity measure that compensates for the lower frequency of noes, and evaluate the pair-wise voting similarities for all lawmakers. Then, voting similarity differences to the affiliated/non-affiliated parties were analyzed for the members in the two major parties according to some internal/external key factors. Finally, similar voting groups were identified and their affiliations were investigated based on the multi-dimensional scaling (MDS) and network analysis techniques. A case study on the $18^{th}$ national assembly of South Korea showed that the cohesion of the members in the 'Hanara' party becomes higher than that of the 'Minju' party as the bill contentiousness increases, whereas the number of elected, local constituency versus proportional representation, and the competition intensity in a local constituency were found to be partially influential to the voting activities of lawmakers. In addition, MDS and network analysis showed that there is a distinctive difference between two parties when all bills are analyzed, whereas the diversity of parties increases in the same group as the bill contentiousness increases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.2678-2688
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• 2014

The purpose of this study is to examine the explanatory power of factors similar change to see what the value of the child's father give faith, grow, grow what kind of participation in the developmental characteristics of infants affected. 1,802 people infants born in 2010, the study is his father, I used the data for the next fiscal year 3 Panel Korea Policy Institute childcare children that target it. Analysis of the data, we have carried out frequency analysis using SPSS18.0, The value of the infant's father a child problem-solving skills, fine motor activity been found to affect the activity. Muscle activity for the father of the infant did not influence variables are. And the infant's communication, personal-social variables that affect the independence turned out to be a father involved in parenting.

• Journal of agriculture & life science
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• v.44 no.5
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• pp.137-146
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• 2010

The GyeongNam Province is one of the regions that have first introduced chrysanthemum farming in Korea since the 1960s. The chrysanthemum growers of The GyeongNam Province had strong competitiveness in production and marketing, so the their income ratios were relatively higher than any other growers of other provinces. The income ratio of The GyeongNam Province, however, has continuously decreased and stays currently below ratios of other provinces. The purpose of this paper is to find out which factors have contributed to the decrease in income ratio of GyeongNam Province. The analysis indicates that the increase in production cost was the main causes of rapid drop in income ratio. It is also worth mentioning that the income ratio falls dramatically when oil price (duty-free oil) rises above 700 won per liter.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.363-363
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• 2019

활성화 함수(activation function)는 기계학습(machine learning)의 학습과정에 비선형성을 도입하여 심층적인 학습을 용이하게 하고 예측의 정확도를 높이는 중요한 요소 중 하나이다(Roy et al., 2019). 일반적으로 기계학습에서 사용되고 있는 활성화 함수의 종류에는 계단 함수(step function), 시그모이드 함수(sigmoid 함수), 쌍곡 탄젠트 함수(hyperbolic tangent function), ReLU 함수(Rectified Linear Unit function) 등이 있으며, 예측의 정확도 향상을 위하여 다양한 형태의 활성화 함수가 제시되고 있다. 본 연구에서는 기계학습을 통하여 수위예측 시 정확도 향상을 위하여 Hybrid 활성화 함수를 제안하였다. 연구대상지는 조수간만의 영향을 받는 한강을 대상으로 선정하였으며, 2009년 ~ 2018년까지 10년간의 수문자료를 활용하였다. 수위예측 알고리즘은 Python 내 Tensorflow의 RNN (Recurrent Neural Networks) 모델을 이용하였으며, 강수량, 수위, 조위, 댐 방류량, 하천 유량의 수문자료를 학습시켜 3시간 및 6시간 후의 수위를 예측하였다. 예측정확도 향상을 위하여 입력 데이터는 정규화(Normalization)를 시켰으며, 민감도 분석을 통하여 신경망모델의 은닉층 개수, 학습률의 최적 값을 도출하였다. Hybrid 활성화 함수는 쌍곡 탄젠트 함수와 ReLU 함수를 혼합한 형태로 각각의 가중치($w_1,w_2,w_1+w_2=1$)를 변경하여 정확도를 평가하였다. 그 결과 가중치의 비($w_1/w_2$)에 따라서 예측 결과의 RMSE(Roote Mean Square Error)가 최소가 되고 NSE (Nash-Sutcliffe model Efficiency coefficient)가 최대가 되는 지점과 Peak 수위의 예측정확도가 최대가 되는 지점을 확인할 수 있었다. 본 연구는 현재 Data modeling을 통한 수위예측의 정확도 향상을 위해 기초가 되는 연구이나, 향후 다양한 형태의 활성화 함수를 제안하여 정확도를 향상시킨다면 예측 결과를 통하여 침수예보에 대한 의사결정이 가능할 것으로 기대된다.

• The Journal of KAIRB
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• v.3 no.2
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• pp.28-36
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• 2021

Purpose: The purpose of this study is to assess the status of the Human research Protection Program (HRPP) within a hospital or a research institute in Korea. Methods: Survey was conducted during June 12th-21th 2019. Survey was distributed to the members of Korean Association of IRB (KAIRB) through each IRB office. Descriptive statistics were performed using SPSS ver. 26. Results: A total of 86 people responded, and 75 (87.0%) answered that they have perceived the HRPP. Seventy out of 86 respondents (81.4%) were conducting internal audit, several institutions were operated simultaneously the other form of audits such as IRB audit, system audit. Regarding the management of Suspected Unexpected Serious Adverse Reaction (SUSAR), 62.8% answered that they have regulation that can decide to suspend the study when there is a risk to subject safety. Among the respondents, 66.3% performed 'Help desk.' Conclusion: In this study, we assessed the current status of HRPP operation at each research institution based on Ministry of Food and Drug Safety (MFDS) HRPP guidelines. The HRPP accredited institution operated the subject protection activities according to this program, and even if the HRPP was not officially operated, the related activities were conducted focusing on the cases that could have a significant impact on the safety of research subjects. In order to ensure the quality of domestic clinical trials and to stably establish the HRPP, efforts at the individual institution level will be required.

• Journal of Industrial Convergence
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• v.19 no.1
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• pp.1-6
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• 2021

The purpose of this study is to find a way to increase the examination rate by presenting the current state of national health examination. To this end, demographic factors(Gender, age, income level, education level) and health factors(Smoking, alcohol, obesity, subjective health status) were selected, and whether the selected factors were different for each group, and the examinees according to the number of hospitals and income level were visualized. As a result, except for subjective health status in health factors, population factors, and number of hospitals were all related to the examination. In addition, among the age factors of the demographic factor, those in their twenties and those with a low income level and those who were underweight among the health factors of obesity had a high rate of non-testing. Therefore, it is considered necessary to promote, support, and educate those untested by these groups.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.55-59
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• 1989

Sodium methyl arsenate has been evaluated as a male sterilizing agent for the system of producing hybrid rice seeds. The compound was the most effective at the concentration of 0.02％. When applied as a foliar spray to four rice varieties at 15 days before heading, sodium methyl arsenate has produced 99％ male sterility. But the most effective time for application of the compound was 5 days before heading because of its phytotoxic effects. Effective application volume of the compound solution has depended on the growth of the plants treated. Varietal difference on the activity of the compound has been detected.