• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.2
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• pp.141-146
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• 2014

This paper suggests a way of generating one-day load curves for performance improvement of peak shaving in a power system. This Peak Shaving algorithm is a long-term scheduling algorithm of PMS (Power Management System) for BESS (Battery Energy Storage System). The main purpose of a PMS is to manage the input and output power from battery modules placed in a power system. Generally, when a Peak Shaving algorithm is used, a difference occurs between predict load curves and real load curves. This paper suggests a way of minimizing the difference by making predict load curves that consider weekly normalization and seasonal load characteristics for smooth energy charging and discharging.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1400-1404
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• 2010

In this study the flow duration curves and load duration curves for Nakdong river basin are analyzed. The TANK model is used as s hydrologic simulation model whose parameters are estimated from 8-days intervals flow data measured by Nakdong River Water Environment Laboratory. also in this study a Minimum Variance Unbiased Estimator(MVUE) is confirmed that it provides satisfactory load estimate. The Seven-Parameter Log Linear Model for estimating Total Organic Carbon(TOC) and Biochemical Oxygen Demand(BOD) loads in Nakdong river using a MVUE.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.9
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• pp.830-839
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• 2010

This study presents a constituent load estimating procedure that can be operated with the present Korean TMDL monitoring system. The modified TANK model is used as a daily river flow simulation model whose parameters are estimated from 8-day intervals flow data. Constituent loads are estimated with the 7-parameter log linear model whose parameters are estimated by the minimum variance unbiased estimator. Results from Nakdong river basin reveals that the proposed procedure provides satisfactory TOC and BOD load estimates. As an application, a representative load duration curve is derived for working out a way to represent the overall hydrologic flux of BOD, COD and TOC at Nakdong river basin. The present water quality can be checked stochastically by Load Duration Curve through this study and presented visually.

• Journal of Astronomy and Space Sciences
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• v.19 no.4
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• pp.263-272
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• 2002

A total of 616 observations (308 in B, 308 in V) to. V523 Cas was made on three nights from October 19 to 21 in 1999 using the 1.8m telescope with 2K CCD camera of the Bohyunsan Optical Astronomy Observatory of KAO. With our data we constructed the BV light curves and determined 4 times of minimum light. We also obtained physical parameters of the system by combined analysis of both light and radial velocity curves using the Wilson-Devinney code.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.315-315
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• 2011

본류와 지류가 합류되는 합류부에서는 배수영향으로 수위가 증가하더라도 수면경사가 완만해져 감속흐름이 발생하고 배수영향을 받지 않는 동수위보다 유량이 감소하는 수리특성이 나타난다. 또한 지류의 유역면적이 본 류의 유역면적과 비슷한 경우 홍수사상에 따라 역류현상이 발생하여 본류 유역에서의 유출이 발생하지 않더라도 본류의 수위가 증가하는 현상이 발생하기도 한다. 따라서 수위-유량관계에 있어서도 복잡한 현상이 발생하여 단일 수위-유량관계곡선을 개발하는데 어려움이 있다. 본 연구에서는 한강과 평창강이 합류되는 각 하천 하류에 위치한 국토해양부 팔괴 수위관측소와 영월 수위관측소에서의 강우-유출 사상에 따라 변이하는 유출 특성을 검토하였다. 우선 강우 사상을 검토하기 위하여 평창강 유역의 대표 강우관측소인 유천 및 방림 강우관측소와 한강 상류유역의 대표 강우관측소인 대기 및 정선 강우관측소의 2010년 3월과 7월의 강우 사상을 비교하였다. 또한 유출 사상을 검토하기 위하여 평창강 유역 하류의 팔괴 수위관측소와 한강 상류유역 하류의 영월 수위관측소의 2010년 3월 15일부터 17일과 7월 17일부터 20일까지 두 사상에 대한 관측자료, 2010년 3월 16일과 7월 17일에 유량측정을 실시하여 확보한 측정자료를 비교 검토하였다. 또한, 홍수사상에 따른 한강과 평창강 합류부에서의 배수영향 및 역류현상을 검토하기 위하여 2008년 7월 및 2010년 9월의 유량측정을 통하여 확보한 측정자료를 바탕으로 수리특성을 검토하였다. 그림 1에는 한강 및 평창강 유역의 대표 강우관측소의 위치와 각 유역 출구점인 수위관측소의 위치를 도시하였다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.4 no.1
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• pp.109-114
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• 1968

In order to investigate the growth pattern of sugar beet in Korea, this experiment was conducted using variety GW 359 at Tae-kwan-ryong, Suwon and Cheju. The results are summarized as follows; 1. At Tae-kwan-ryong, early growth stage was relatively long and during higher growing stage plants showed resistance to leaf spot disease, and vegetative maturing started from about September 15th. Top and root growth showed normal curve but it is considered that the early maturing variety will reduce the early growing period and prolong the vegetative maturing period. 2. At Suwon, the growth of top part was favorable until late of July but hereafter leaf spot disease brought death to the 25-35 leaves of top part and regenerated again in October. Consequently, sugar content of root showed changes from decrease to increase. Root weight increased from July to harvest season continunousely but showed abnormal growing curve. This indicates that Suwon is not proper place for sugar beet cultivation. 3. At Cheju, early growing stage was shorter about 15 days than that of Tae-kwan-ryong. Normal growth and long-maturing days favored the sugar accumulation in roots. But it is necessary to introduce non-bolting variety in autumn-winter season culture. 4. Sugar beet could be cultivated economically at Tae-kwan-ryong with 600-800 meter altitude for summer crop and at Cheju for winter crop, but Suwon is considered to be unfavorable for sugar beet.

• International Journal of Highway Engineering
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• v.14 no.1
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• pp.95-102
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• 2012

This study has been conducted to characterize the relations between the accident rate and the overlap section elements where the horizontal alignment and vertical alignment are overlapped. The researches were performed on Horizontal curve sections of 4-lane highways with 100km/h of design speed and speed limit. Korea Highway Corporation's Geographic Figurative Information System was adopted for geometric organization and Highway Traffic Accident Statistics was used. The results reveal that sections made of a single slope without vertical curve has greater accident rate than those with vertical curve, and that sections with 1 vertical curve are higher in the accident rate than those with over 2 vertical curve. For the sections with 1 vertical curve, SAG sections are higher than CREST sections and for the previous straight section of horizontal curve are higher than curved ones. In particular, when the road surface is wet, the accident rate is closely related with SAG vertical curves or leftward horizontal curved sections. This study will have meanings that it proposes the importance of design of road alignment by taking consideration of 3D synthetic alignment conditions for improvement of the road safety.

• Journal of Environmental Impact Assessment
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• v.28 no.1
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• pp.35-48
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• 2019

Long term flow measurement and water quality analysis data need to determine the target and allowable load for each basin in Total Water Pollution Load Management System (TWPLMS). The Load Duration Curve (LDC) is analyzed the relationship between flow data and water quality, and evaluates the pollutant load characterization by flow conditions. LDC of Kyeongancheon is created by the Flow Duration Curve (FDC) that was analyzed 8-day interval measured flow data from 2006 to 2015 and numeric water quality target in Kyeongancheon. As a result of this study, it is necessary to manage the point source pollutant because the numeric water quality target is not satisfied in the low flows. Also the numeric water quality target has been exceed for four months from March to June of the year and continuous and systematic watershed management is required to satisfy the numeric water quality target.

• Journal of Astronomy and Space Sciences
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• v.19 no.1
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• pp.39-46
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• 2002

BV observations for V523 Cas were performed with 1.8m telescope and 2K CCD camera at Bohyunsan Optical Astronomy Observatory, Korea, on October 27, 1999. ${\Delta}m$ light curves for 11 comparison objects were made. It was found that their light curve slopes are different each other. Factor analysis for items of slope, (b-v) , magnitude, X pixel, and Y pixel results that there is strong correlation between the slope and the location (X,Y). It might be due to problems of CCD cooling system.

• Journal of the Korea Convergence Society
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• v.7 no.4
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• pp.133-140
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• 2016

This paper suggests designing how to acquire English vocabularies on the smart devices based on the research that a ground-breaking English Vocabulary Learning Contents needs developing. The method makes it possible to develop the contents which helps the learners to master English vocabularies effectively on the smart phone. The core idea of this paper is as in the following: 1) English learners learn 30 vocabularies for three minutes 10 times (one is for a new learning and the other nine ones are for reviews about the first learning) a day. 2) Considering Ebbinghaus Forgetting Curve, the reflection study proposes to provide the learners with three times' reviews: one day, 10days, and 30days later from which they learn the first 30 vocabularies. This contents is mainly made up of 5 developing sections (1)to generate App ID, (2)to access App, (3)to set up Alarm, (4)to process Word learning, and (5)to monitor the result of learning. This proposed idea is optimized to enhance the memory by Ebbinghaus Periodic Repetitive Method, which makes the learners satisfied with their English vocabulary learning.