• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.5
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• pp.149-162
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• 2018

It is necessary to select the appropriate global climate model (GCM) to take into account the impacts of climate change on integrated water management. The objective of this study was to develop the selection technique of representative GCMs for uncertainty in climate change scenario. The selection technique which set priorities of GCMs consisted of two steps. First step was evaluating original GCMs by comparing with grid-based observational data for the past period. Second step was evaluating whether the statistical downscaled data reflect characteristics for the historical period. Spatial Disaggregation Quantile Delta Mapping (SDQDM), one of the statistical downscaling methods, was used for the downscaled data. The way of evaluating was using explanatory power, the stepwise ratio of the entire GCMs by Expert Team on Climate Change Detection and Indices (ETCCDI) basis. We used 26 GCMs based on CMIP5 data. The Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios were selected for this study. The period for evaluating reproducibility of historical period was 30 years from 1976 to 2005. Precipitation, maximum temperature, and minimum temperature were used as collected climate variables. As a result, we suggested representative 13 GCMs among 26 GCMs by using the selection technique developed in this research. Furthermore, this result can be utilized as a basic data for integrated water management.

• Journal of Korea Water Resources Association
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• v.52 no.3
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• pp.195-206
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• 2019

In this study, the vulnerable period assessment method for weekly groundwater resources management was developed considering correlation between data of groundwater level, river level, precipitation applying critical infiltration concept. The vulnerable periods of 3 case study were assessed using data of groundwater, precipitation, river level, and results were compared. The weights for between observation stations were calculated using correlation of groundwater, precipitation, river level data, and weights that could be considered recently trend of data for each observation station. The vulnerable period was assessed using final calculated weights and multi criteria decision method, compared result for each case study. The developed method can be a quantitative basis for the establishment of efficient groundwater resources management and the decision of specific countermeasure applyment.

• Journal of the Society of Disaster Information
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• v.7 no.4
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• pp.316-327
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• 2011

The purposes of this study are to investigate various experience factors that special guards firstly appointed calculate during the occupational socialization and suggest the preliminary data which is necessary to the establishment of educational service strategy of preliminary special guard and security guard. So, in-depth interviewing and ethnographic study were conducted for 4 special guards firstly appointed. As the result, the occupational socialization process of special guards firstly appointed are quickening period, preparatory period, adaptation period and conflict/maturity period. The first, quickening period is a decision of family background, exercise experience and university entrance. The second, preparatory period is certificates and mentor of department vision, university curriculum and occupational preparation. The third, adaptation period is occupational specialty, occupational professionalism, occupational satisfaction, motivation and company colleagues. The forth, conflict/maturity period is job stress, turnover, conflict in company, efforts for self-development and prospect of job. Therefore, this study will be able to be applied as a guide for special guard's performance improvement and provide educational preliminary data for following-up studies.

• Journal of Korean Neurosurgical Society
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• v.67 no.2
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• pp.186-193
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• 2024

Objective : The treatment paradigm for acute ischemic stroke has undergone several major changes in the past decade, contributing to improved patient prognosis in clinical practice. However, the extent to which these changes have affected patient prognosis in the real-world is yet to be clarified. This study aimed to evaluate the real-world impact of modern reperfusion therapy for acute ischemic stroke using data from the National Health Insurance Service in Korea. Methods : This study included patients aged 18-80 years who were admitted via the emergency room with an I63 code between 2011 and 2020. The rates of intravenous thrombolysis use and endovascular treatment according to the year of admission were investigated. Furthermore, the rates of decompressive craniectomy and 3-month mortality were also analyzed. The 10-year observational period was divided into three periods based on the 2015 guideline change as follows : prior, 2011-2014; transitional, 2015-2016; and modern, 2017-2020. Results : A total of 307117 patients (mean age, 65.7±10.9 years) were included, and most patients were male (59.7%). The rate of endovascular treatment gradually increased during the study period from 0.71% in the prior period to 1.32% in the transitional period and finally to 1.85% in the modern period. Meanwhile, the 3-month mortality rate gradually decreased from 4.78% in the prior period to 4.03% in the transitional period and to 3.71% in the modern period. Conclusion : In Korea, the mortality rate decreased as the rate of modern reperfusion therapy increased in patients with acute ischemic stroke. Overall, technical and scientific advances in reperfusion therapy have improved the outcome of patients with acute ischemic stroke in Korea.

• Journal of Korea Water Resources Association
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• v.55 no.3
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• pp.177-189
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• 2022

The purpose of this study is to apply the d4PDF (Data for Policy Decision Making for Future Change) constructed from a large-scale ensemble climate simulation to estimate the probable rainfall with low frequency and high intensity. In addition, this study analyzes the uncertainty caused by the application of the frequency analysis by comparing the probable rainfall estimated using the d4PDF with that estimated using the observed data and frequency analysis at Geunsam, Imsil, Jeonju, and Jangsu stations. The d4PDF data consists of a total of 50 ensembles, and one ensemble provides climate and weather data for 60 years such as rainfall and temperature. Thus, it was possible to collect 3,000 annual maximum daily rainfall for each station. By using these characteristics, this study does not apply the frequency analysis for estimating the probability rainfall, and we estimated the probability rainfall with a return period of 10 to 1000 years by distributing 3,000 rainfall by the magnitude based on a non-parametric approach. Then, the estimated probability rainfall using d4PDF was compared with those estimated using the Gumbel or GEV distribution and the observed rainfall, and the deviation between two probability rainfall was estimated. As a result, this deviation increased as the difference between the return period and the observation period increased. Meanwhile, the d4PDF reasonably suggested the probability rainfall with a low frequency and high intensity by minimizing the uncertainty occurred by applying the frequency analysis and the observed data with the short data period.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.3
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• pp.33-43
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• 2011

Objectives : The purpose of this study was to investigate the influence of modified fasting therapy using fermented herbal medicine on the changes of body compositions. Methods : This study was carried out on 11 patients who carried out modified fasting therapy using fermented herbal medicine. They went through reducing food intakes period(7 days), fasting period(10~14 days) and refeeding period(10~14 days). Body compositions(weight, BMI(body mass index), skeletal muscle mass, body fat mass, percent body fat, basal metabolic rate, waist-hip ratio, visceral fat area) were measured at each state. And then the data was analyzed. Results : 1. The weight and BMI decreased during the reducing food intakes period and the fasting period, and increased during the refeeding period. But the weight and BMI decreased during the fasting therapy period, as a whole. 2. The skeletal muscle mass decreased during the fasting period and increased during the refeeding period. As the final outcome, for the whole fasting therapy period, decrease of skeletal muscle mass didn't show significance. The body fat mass and percent body fat decreased during the reducing food intakes period, the fasting period and the refeeding period. 3. The basal metabolic rate decreased during the fasting period and increased during the refeeding period. As the final outcome, for the whole fasting therapy period, decrease of basal metabolic rate didn't show significance. 4. The waist-hip ratio decreased during the fasting period and the refeeding period. The visceral fat area decreased during the fasting period and refeeding period. Conclusions : Results from this investigation showed that modified fasting therapy using fermented herbal medicine have positive effects on changes of body compositions. This results are expected to compensate the defects of existing fasting therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3815-3817
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• 2013

Background: Breast cancer is a common cancer worldwide. With the establishment of Thailand's population-based cancer registry and availability of complete data from 2002-2011, it is of interest to investigate the epidemiologic and clinic-pathological profiles of breast cancer based on the population-based registry data. Methods: The data of all breast cancer patients in the registry for the period of 2002-2011 were included. All medical records of the patients diagnosed from documents of National Cancer Registry of Thailand were retrieved and the following information abstracted: age, clinical characteristics, and histological variables. Thailand census data for the period of 2002-2011 were used to provide the general population's statistics on age, gender, and other related demographic factors. Results: Over the 10 year-period, 7,711 breast cancer cases were included. The disease incidence under age 40 years was relatively low (4.13/$10^5$) while the incidence in the age groups 40 and older was very high (39.2/$10^5$). The vast majority of breast cancer cases (88.8%) were diagnosed by histology as primary lesions in the breast. The most common of patients with breast cancer (36.4%) had regional lymph node involvement and the most common of histopathology diagnosed in patients (84.2%) was an infiltrating duct carcinoma. Conclusions: This study showed a high incidence of breast cancer in older subjects, and high rate of breast cancer in Thailand. Future studies should explore clinical and molecular disease patterns.

• Journal of Sensor Science and Technology
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• v.27 no.3
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• pp.175-181
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• 2018

In this paper, we introduce a new dimming control method in a visible light communication (VLC) system wherein byteinversion is adopted for flicker-free transmission. In the VLC transmitter, the original and the inverted data were sent sequentially and the remnant time in one period was used for the dimming control of the LED light. In the VLC receiver, only the original data was recovered using the gating signal whose width was the same as the length of the original data. In our experiments, the dimming control ranges were measured to be 22%-53%, 11%-76%, and 5%-88% of the CW LED light when the data rates were 9.6, 19.2, and 38.4 kbps, respectively. In this system, we used a 240-Hz sync pulse whose period was 4.16 ms, which was shorter than the maximum flickering time period of 5 ms that is generally considered to be safe. This configuration is very simple and useful in constructing indoor wireless sensor networks using the flicker-free LED lamps with dimming control capability.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.256-261
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• 2004

Due to the problems of global warming, the frequency of meteorological extremes such as droughts, floods and the annual rainfall amount are suddenly increasing. Even though the increase of greenhouse gases, for example, is thought to be the main factor for global warming, its impact on global climate has not yet been revealed clearly in rather quantitative manners. Therefore, tile objective of this study is to inquire the change of precipitation condition due to climate change by global warming. In brief, this study want to see its assumption if rainfall quantile estimates are really changing. In order to analyze the temporal change, the rainfall quantile estimates at the Seoul rain gauge stations are estimated for the 21-year data period being moved from 1908 to 2002 with 1-year lag. The main objective of this study is to analyze the variability of rainfall quantile estimates using four methods. Next, The changes in confidence interval of rainfall quantile are evaluated by increasing the data period. It has been found that confidence interval of rainfall quantile estimates is reduced as the data period increases. When the hydraulic structures are to be designed, it is important to select the data size and to re-estimate the flood prevention capacity in existing river systems.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.3
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• pp.351-361
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• 2013

In this study the Principal Component Analysis (PCA) was applied to flow data in a water distribution pipe system to analyze the relevance between the flow observation dates, which have the outliers of observed night flows, and the maintenance records. The data was obtained from four small size water distribution blocks to which 13 maintenance records such as pipe leak and water meter leak belong. The flow data during four months were used for the analysis. The analysis was carried out to identify an appropriate analysis period for a PCA model for a water distribution block. To facilitate the analyses a computational algorithm was developed. MATLAB was utilized to realize the algorithm as a computer program. As a result, an appropriate PCA period for each of the case study small size water distribution blocks was identified.