• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.2
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• pp.1-12
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• 2011

Korean government have supported the foreign internship system for plant industry to bring up the professional personnel for this industry. The Korea Plant Industry Association(KOPIA) has sent 400 interns each year to the foreign plant construction field since 2009. The purpose of this study is to analyze this foreign internship system in quantitative aspects and to suggest the several improvements on this system. In 2010, 402 interns, which exeeds the primary object 400, were sent to the foreign field and this study analyzed the 2010 results by monthly, by major of participating interns, and by the business type of participating company. Finally, this study suggests several improvements for this internship system as follows : 1) the enlargement of the internship system into employement, 2) the need for the public relations(PR) of this systems, 3) the establishment of cooperating network among participating universities, and 4) the enforcement of network among participating company, KOPIA, and paricipating interns.

• JOURNAL OF ELECTRICAL WORLD
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• s.290
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• pp.90-94
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• 2001

일본의 수력발전소는 국산에너지의 주력산업으로 클린하며 또한 재생 가능한 에너지로서 수백kW의 소수력에서 500MVA급의 대용량 양수까지, 여러 목적에 맞는 역할을 다하고 있다. 특히 양수발전소는 전력계통의 부하 평활화라는 중책을 담당하고 있으며, 앞으로 전력수요의 증가에 따라 더욱더 그 중요도는 증가할 것이다. 미쓰비시전기의 양수발전소의 단위용량은 1990년대 전반까지는 367MVA(도쿄전력 신고뢰천)가 최대였으나 ''98년 운전 개시한 간사이 전력 오다다양목의 400MVA, 2000년 운전 개시한 국내최대용량의 도쿄전력 갈야천의 475MVA로 최근 대용량화가 진전되어 그 대용량기술의 진보는 크게 주목을 받고 있다. 또 주기의 회전속도에 있어서도 400min${^-1}$급에서 500min${^-1}$로, ''보다 더 고속대용량화'' 시대에 돌입하였다고 할 수 있다. 또한 수력발전소는 일찍부터 일인화$\cdot$무인화에 의한 감시제어의 자동화$\cdot$성력화가 추진되어 왔다. ''50년대의 일인화제어를 거쳐'' 60년대에는 원방감시제어화에 의해 완전자동화$\cdot$무인화를 실현하였다. 그 후에도 디지털기기의 응용에 의하여 감시제어장치의 고기능화가 진전되고 또 보호도 포함한 토털디지털시스템도 구축되어 있다. 또한 중소수력발전소에 대하여는 종래 분산시스템이었던 시퀀서/거버너/AVR을 1CPU로 실현한 일체형배전반이 차후의 중소 수력제어장치의 주력기종이 되고 특히 범용컨트롤러를 적용한 시스템도 실용화되어 가고 있다. 본고에서는 최근의 수차, 발전기의 고속$\cdot$대용량화를 중심으로 한 동향과 감시제어시스템의 기술동향을 소개함과 동시에 앞으로의 전망에 대하여 기술하고자 한다.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.521-524
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• 2008

In addition the typhoon 'Lusa' of year 2002 has resulted 5,400 billion won of property damage and the damages for roads and railroads were approximated to be 2,860 billion won at 12,377 locations holding 53% damage of total. It was reported that the property damage due to the 2003 typhoon, 'Maemi' was 4,200 billion won. The recent typhoon, 'Aewinia', caused the 1,400 billion-won property damage including sweeping and flooding of 127 roads and 65 rivers, respectively. Therefore, this paper presented to estimate drainage size for debris flow

• Journal of The Geomorphological Association of Korea
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• v.20 no.4
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• pp.101-115
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• 2013

11 alpine wetlands at the upper reaches of Bangtae River on a high flat summit around Mt. Jeombong were found. Two core samples(JB-1 and JB-2) among them were collected in order to reconstruct paleovegetation history and climate change using pollen analysis. Pinus and Quercus dominated at the wetland of JB-2 with a deep water depth were developed from 1,700 yr BP to 1,000 yr BP of the pollen zone I. Subsequently Quercus dominated in the pollen zone II from 1,000 to 400 yr BP, and it is supposed that warm weather prevailed with oak climax forest corresponding to the Medieval Warm Period. Moreover, sphagnum grew densely in the alpine wetlands and the wetlands were extended widely on the summit around Mt. Jeombong with the beginning of subzoneIIc at JB-2. The pollen zone III from 400 yr BP to the present with an increase in Pinus and a decrease in Quercus suggests cold climates under the Little Ice Age. Moreover, human disturbances at JB-2 were more significant than those at JB-1, based on the increase in Pinus.

• Journal of Korea Water Resources Association
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• v.56 no.2
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• pp.91-101
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• 2023

In this study, we estimated the concentration of chlorophyll-a (Chl-a) using hyperspectral water surface reflectance in an inland weir (Baekjae weir) and estuarine reservoir (Namyang Reservoir) for monitoring the occurrence of algae in freshwater in South Korea. The hyperspectral reflectance was measured by aircraft in Baekjae Weir (BJW) from 2016 to 2017, and a drone in Namyang Reservoir (NYR) from 2020 to 2021. The 30 reflectance bands (BJW: 400-530, 620-680, 710-730, 760-790 nm, NYR: 400-430, 655-680, 740-800 nm) that were highly related to Chl-a concentration were selected using permutation importance. Artificial neural network based Chl-a estimation model was developed using the selected reflectance in both water bodies. And the performance of the model was evaluated with the coefficient of determination (R²), the root mean square error (RMSE), and the mean absolute error (MAE). The performance evaluation results of the Chl-a estimation model for each watershed was R²: 0.63, 0.82, RMSE: 9.67, 6.99, and MAE: 11.25, 8.48, respectively. The developed Chl-a model of this study may be used as foundation tool for the optimal management of freshwater algal blooms in the future.

• Korean Journal of Health Education and Promotion
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• v.24 no.5
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• pp.69-85
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• 2007

Purpose: The purpose of this study is to clarify the traits of differences supposed as secular differences in physical growth between samples of children and youth in 1999 and 2005, and to identify the need of children and youth for health promotion. Methods: Two samples of different cohort were selected. The first one was consisted of 231 boys and 346 girls in 1999. And the other was consisted of 171 boys and 400 girls in 2005. Then the longitudinal growth distance data were collected from their cumulative health examination records. Results: The 2005 were larger in growth distances of stature, body weight, sitting height, and chest girth a at all ages from 6 to 16 in both boys and girls, so it could be concluded that a certain positive shift in growth process appeared in such a short duration. The 2005 were larger in growth velocity before peak age and also after peak age in body weight, but only in the term after peak age significant secular differences were found in stature for both sexes. As far as the growth distance concerned, the 2005 boys were ahead of the 1999 boys from 0.28-1.02 years and the 2005 girls from 0.32 to 0.81 years. In growth distance. Only in peak velocity, significant secular change was recognized in both sexes, any positive evidences of appearance of secular change were not found in peal age. In such derived physical indices as BMI, body weight index, sitting height index, and chest girth index, obvious evidences of secular change appearance were found.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.3
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• pp.128-134
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• 2016

An analysis of the main factors and its degree of impact on power production is performed against the landfill gas power plant in S landfill site. The number of normal operation (50 MWh & 24 hr) days was 70.9% to the total number of operation days from 2007 to 2014, and the percentage of the actual power production was 79.3% of 3,428,400 MW which is the theoretical maximum estimation. The ratio of factors that accounted for the efficiency of power production are: 44.0% of repairing of the defect and regular servicing, 37.4% of cut-down operation due to hydrogen sulfide, and 18.6% of air pre-heater washing, respectively. Yet, considering that the cut-down operation due to hydrogen sulfide was carried out for only two years, the high concentration of hydrogen sulfide was the most influential factors on landfill gas power production. The long-term power production was analyzed as 35.9 MWh in 2018, and the constant drop is anticipated, resulting in 16.6 MWh by 2028, and under 8.4 MWh in 2038.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.61.2-61.2
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• 2013

우리나라 최초의 거대과학 장치인 포항방사광가속기(PLS)는 지난 16년(1994~2010) 동안 국내외 이용자에게 제3세대 방사광을 제공했다. 최초 2기의 빔라인을 시작으로 꾸준하게 빔라인 증설과 성능개선을 위해 노력해 왔다. 지속해서 늘어나는 방사광 이용자 수와 더욱더 좋은 수준의 방사광 요구에 부응하기 위하여 2009년부터 3년 동안 가속장치의 성능향상사업(PLS-II)을 마쳤다. PLS-II는 PLS 대비에너지와 빔전류는 3 GeV, 400 mA로 늘리는 반면 빔의 크기는 크게 줄이고 빔안정성을 개선한 고품질 X-선 방사광 발생장치이다. 2012년부터 16기의 삽입장치 빔라인을 포함한 30기의 빔라인을 가동하여 이용자 지원을 하고 있으며 초전도케비티 설치를 포함한 목표 성능의 확보에도 많은 노력을 기울이고 있다. 현재는 6 nm-rad의 빔에 미턴스, 3-GeV전자빔, 약 0.5 ${\mu}m-rms$ 빔안정도를 가진 200 mA Top-up 운전으로 빔을 제공 하고 있으며 2014년 말에는 저장전류 400 mA급의 PLS-II 목표치로 운전할 계획이다. 본 발표에서는 포항가속기의 25년 역사를 돌아보고 가속장치의 건설에 얽힌 이야기, 중요장치 그리고 운전과 빔제공에 관한 내용, 특히 핵심 운전가치인 빔안정성을 개선하고 유지하기 위한 노력을 빔운전 측면과 진공을 포함한 엔지지어링 측면에서 언급하고자 한다. PLS 건설부터 현재 운용 중인 30기의 빔라인에서 수행된 연구 성과의 통계에 대하여 훑어보고 X-선 산란과 광전자분광을 이용한 구조, 성분 및 물성분석, 그리고 이미징 등의 분야에서 나온 탁월한 연구 결과를 살펴본다. 앞으로 건설될 신규 빔라인과 빔라인의 향후 운영 방향을 소개한다. 마지막으로 지금 포항가속기연구소에서 건설 중인 제4세대 가속기(X-선 자유전자레이저) 프로젝트의 개요 및 건설 현황과 함께 앞으로 기대되는 새로운 과학에 대하여도 소개하고자 한다.

• Journal of Korea Water Resources Association
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• v.53 no.12
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• pp.1109-1117
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• 2020

In this study, results of RUSLE which is most popular equation for estimating sediment and MSDPM and LADMP have been compared and analyzed by applying to real watershed of mountain area. Crop factor (C), preservation factor (P), and soil erosion factor (VM) of RUSLE can be subjectively selected and differently applied. Therefore, effects of those factors were estimated and compared with different values of factors. Furthermore, sediment yield has been estimated by MSDPM and LADMP according to 10, 20, 30, 50, 100, and 200 year return period. From the results, it was found that sediment yield can be resulted with 400% diffrence. And it was also found that MSDPM and LADMP can be applied in mountain area of Korea.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2268-2270
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• 2005

전력계통분야에서 송전전압의 초고압화는 꾸준히 연구가 진행되는 과제중의 하나이다. 국내에서는 당사가 참여한 한전(KEPCO)의 영서${\sim}$ 영등포 345kV XLPE 지중T/L 건설공사가 2003년 6월 20일 국내 최초로 준공된 이후 현재까지 아무런 문제없이 운전중에 있으며, 향후 그 수요가 꾸준히 증대될 것으로 예상되고 있다. 전 세계적으로 살펴보더라도 400KV급 XLPE 케이블 및 부속재에 대한 수요가 꾸준히 확대되고 있다. 그러므로, 당사에서는 국내에서 345KV 케이블 및 부속재를 개발한 기술력을 바탕으로, 한 단계 업그레이드된 해외시장에서 세계의 업체들과 경쟁하기 위해, 400KV 2500sq.mm XLPE 케이블 및 부속재를 성공적으로 개발하였다. 이에 관해 소개하고자 한다.