• Magazine of the Korean Society of Agricultural Engineers
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• v.22 no.3
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• pp.75-87
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• 1980

Most hydro]ogic phenomena are the complex and organic products of multiple causations like climatic and hydro-geological factors. A certain significant correlation on the run-off in river basin would be expected and foreseen in advance, and the effect of each these causual and associated factors (independant variables; present-month rainfall, previous-month run-off, evapotranspiration and relative humidity etc.) upon present-month run-off(dependent variable) may be determined by multiple regression analysis. Functions between independant and dependant variables should be treated repeatedly until satisfactory and optimal combination of independant variables can be obtained. Reliability of the estimated function should be tested according to the result of statistical criterion such as analysis of variance, coefficient of determination and significance-test of regression coefficients before first estimated multiple regression model in historical sequence is determined. But some error between observed and estimated run-off is still there. The error arises because the model used is an inadequate description of the system and because the data constituting the record represent only a sample from a population of monthly discharge observation, so that estimates of model parameter will be subject to sampling errors. Since this error which is a deviation from multiple regression plane cannot be explained by first estimated multiple regression equation, it can be considered as a random error governed by law of chance in nature. This unexplained variance by multiple regression equation can be solved by stochastic approach, that is, random error can be stochastically simulated by multiplying random normal variate to standard error of estimate. Finally hybrid model on estimation of monthly run-off in nonhistorical sequence can be determined by combining the determistic component of multiple regression equation and the stochastic component of random errors. Monthly run-off in Naju station in Yong-San river basin is estimated by multiple regression model and hybrid model. And some comparisons between observed and estimated run-off and between multiple regression model and already-existing estimation methods such as Gajiyama formula, tank model and Thomas-Fiering model are done. The results are as follows. (1) The optimal function to estimate monthly run-off in historical sequence is multiple linear regression equation in overall-month unit, that is; Qn=0.788Pn+0.130Qn-1-0.273En-0.1 About 85% of total variance of monthly runoff can be explained by multiple linear regression equation and its coefficient of determination (R2) is 0.843. This means we can estimate monthly runoff in historical sequence highly significantly with short data of observation by above mentioned equation. (2) The optimal function to estimate monthly runoff in nonhistorical sequence is hybrid model combined with multiple linear regression equation in overall-month unit and stochastic component, that is; Qn=0. 788Pn+0. l30Qn-1-0. 273En-0. 10+Sy.t The rest 15% of unexplained variance of monthly runoff can be explained by addition of stochastic process and a bit more reliable results of statistical characteristics of monthly runoff in non-historical sequence are derived. This estimated monthly runoff in non-historical sequence shows up the extraordinary value (maximum, minimum value) which is not appeared in the observed runoff as a random component. (3) "Frequency best fit coefficient" (R2f) of multiple linear regression equation is 0.847 which is the same value as Gaijyama's one. This implies that multiple linear regression equation and Gajiyama formula are theoretically rather reasonable functions.

• Journal of Korea Water Resources Association
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• v.40 no.11
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• pp.851-859
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• 2007

In this study, the chukwookee data were evaluated by applying that for the historical rainfall frequency analysis. To derive a two parameter log-normal distribution by using historical data and modem data, censored data MLE and binomial censored data MLE were applied. As a result, we found that both average and standard deviation were all estimated smaller with chukwookee data then those with only modern data. This indicates that rather big events rarely happens during the period of chukwookee data then during the modern period. The frequency analysis results using the parameters estimated were also similar to those expected. The point to be noticed is that the rainfall quantiles estimated by both methods were similar. This result indicates that the historical document records like the annals of Chosun dynasty could be valuable and effective for the frequency analysis. This also means the extension of data available for frequency analysis.

• Journal of the Korean Society of Costume
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• v.55 no.7 s.98
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• pp.142-155
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• 2005

This study shows historical Gagye(가계) The process of change and Characteristics through analysis on the old documents, related papers, and visual data, and represents its meaning in Korean Clothing history through analysis on originality of Korean Gagye(가계) style. Gagye(가계) is the cubic hair style which add other accessories on hair and is divided into two; Gagye(가계) and Chegye(체계) according to its material, role, and function. And Korean Gagye(가계) has been transformed suited to the times and showed various features according to pattern, wearing, and decoration aspect. In its style aspect, Korean Gagye(가계) style shows Hwangye type, Sseugae type, Gogye type, Dagye type, and Braided & coiled hair type. Each shows historical features. In its Wearing aspect, Gagye(가계) style shows Wearing ornamental hairpin on the head, Wearing Rag Ribbon on the head, and Attaching (Detaching) Wearing. And in its Decoration aspect, Gagye(가계) style shows decoration with accessories, one with flower arrangement, and one with shaking.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.232-234
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• 2005

This paper will produce a practical, accurate method for computing the equipment forced outages rate (FOR) based on 10 years of historical equipment outages data. Also, the location and weather conditions on outages are included. The computed FOR are ranked as 4 groups (presumably high, medium, low & very low) depending on the frequency (up to # times per year) and a consistent framework for transmission reliability performance table is developed based on these groupings. Our intent is to use this framework as guidelines for contingency analysis criteria in system planning / operation departments. The concepts are illustrated on the 2005 KEPCO power system.

• Journal of The Korean Association For Science Education
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• v.5 no.2
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• pp.139-145
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• 1985

This study was undertaken to analyze the research trends on science education in Korea. In this study the analysis for of trends of researches on science education, nine areas such as historical change of science Education, Processes of science learning science curriculum, science instruction, teaching-learning materials and equipment for science education, valuation on science education, survey on Korean science education, policy and management of science education, and natural science, were chosen for the analysir. All science education. thesis and dissertations in Korea, papers of science education published by the science center of the Seoul National University and the papers of the Journal of the Korean Association of Res Search in science Education were analyzed. The findings of this study are as follows: 1. Seventy percentile of science educational thesis and dissertations are on natural science areas. 2. About 14% of all papers being sampled is in science curriculum research category. There are few research studies on historical changes of science education, and teaching-learning materials and equipments for science education.

• Journal of Korean Medical classics
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• v.26 no.1
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• pp.71-77
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• 2013

Objective : To clarify the features of needling method in the Zhenjiu Jiayijing, the needling depth and needling treatment time were sorted out. Method : According to the analysis, we can identify the crucial factors of the needling features. Result : Compared with the needling related content of Huangdi Neijing(黄帝内经), the historical outline of the needling development could be found and the ancient acupuncturing process was reappeared with a historical perspective. This research will provide guidance for the literature research and clinical application. Conclusion : Zhenjiu Jiayijing, also an important and valuable literature, will provide more evidence or clues for depth and treatment time of needling, which will be helpful and meaningful in clinic.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.315-318
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• 2008

The purpose of this study is to examine residential cultural attributes by analysing typological and living characteristics while focusing on various types of houses located in Gyeongju city, based on the historical and cultural background of the city. In this study, it is important to suggest methods for planning residential construction which satisfies requirements of Gyeongju citizens for living environment and considers its cultural and historical contexts. This study was performed using housing type-related questionnaires with 203 residents to find out their current living types, as well as their preferable living types in the future, during the period from the 16th to 18th day of August 2007. Analysis was performed using the SPSS 14, a statistical program, and statistically significant results were drawn from the analysis.

• Journal of the Korea Safety Management & Science
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• v.14 no.2
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• pp.253-263
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• 2012

Although the national technical qualification scheme has a historical background for thirty-five years, it hasn't any study of an obvious cause analysis, effective counterplan and analysis relation to its historical changes. This paper analyses the internal and external factors of technical qualification policy of the Human resources development service of Korea using PEST and SWOT and surveys the influence on its environment and the variation cause of the ratio of successful applicants to the qualification scheme. This paper also suggests systematically the direction for development of the technical qualification scheme using FMEA. Thus, this study assists to construct rapidly a correspondence system to the environment change simultaneously to determine decision making to the marketing policy.

• Structural Monitoring and Maintenance
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• v.2 no.4
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• pp.301-318
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• 2015

This is the story of a bell-tower and its monitoring. The Civic Tower in Portogruaro is a 59 m high masonry bell-tower, originally built in the XIII century, today leaning more than a meter out of plumb. Since 2003, the building inclination has been continuously monitored with an optical inclinometer in an effort to see whether the tilt is still in progress. When the monitoring started, it was thought highly unlikely that the Tower would tilt further. After three years of monitoring and historical investigation, this idea was completely overturned. We show here how the initial view developed to a final awareness via a probabilistic analysis of the information acquired, based on Bayesian logic. We illustrate how the joint use of instrumental monitoring and historical documentation allowed timely recognition of signs of ongoing tilting and accurate calculation not only of the mean inclination trend, but also the credibility of this information.

• Smart Structures and Systems
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• v.23 no.4
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• pp.337-345
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• 2019

This work resumes a research that proposes the use of the technique based on the dissipation energy of the shape memory alloy (SMA) ties. It focuses principally on the assessment of the effectiveness of the use of these smart materials on displacements, accelerations and the stresses of the minaret of the great mosque of Ajloun in Jordan. The 3-D finite element model of the minaret is performed by the ANSYS software. First of all, the proposed model is calibrated and validated according to the experimental results gathered from ambient vibration testing results. Then, a nonlinear transient analysis is considered, when the El-Centro earthquake is used as the input signal. Different simulating cases concerning the location, number and type of SMA devices are proposed in order to see their influence on the seismic response of the minaret. Hence, the results confirm the effectiveness of the proposed SMA device.