• KIEE International Transactions on Power Engineering
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• 제3A권3호
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• pp.168-176
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• 2003

The Korea Electric Power Corporation (KEPCO) has installed an 80 MY A Unified Power Flow Controller (UPFC) at its 154㎸ 'Kang-Jin Substation in South Korea. The device, manufactured by Siemens & Hyusung, has been operational since October 2002. The Korea Electric Power Research Institute (KEPRI), a division of KEPCO was tasked to study operational strategies that could be employed for the UPFC and surrounding reactive support devices concerning problems of low voltages and overloads in the Mokpo & Gwangju areas. Particular apprehension surrounded the possibility of delay in the installation of a new 345㎸ transmission line from 2005 to beyond 2010. The studies were to specifically determine whether these problems could be eliminated by application of a UPFC. The analysis included determining the UPFC operating point under various conditions, investigations of the coordination between the UPFC and a HYDC line terminating in this area, and the design of a supplementary damping controller for the UFPC. This paper summarizes the results of those studies, demonstrating the dynamic characteristics of the operation of this UPFC operation in the Korean power system.

• 한국간호교육학회지
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• 제19권3호
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• pp.384-395
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• 2013

Purpose: This study aimed to investigate the nurse's image and role projected in media and perceived by elementary, middle and high school students. Methods: Data were collected from 544 students in J city, Korea during December 2010 to February 2011. The nurse's image was measured by the instrument developed by Yang (1998). Nursing experiences and nurse's role in media was measured by self-administered questionnaires with 8 questions. Statistical analysis was made with t-test and ANOVA using SPSS win 18.0. Result: The score on personal image was the highest, while the score on social image was the lowest. Elementary school students reported a positive image compared with middle and high school students. Male students had a more positive image than female students. Of various media, students had more experiences related to nurses from TV rather than internet sites, books and newspaper/magazines. Especially, the nurse's role on TV 'seemed to be an assistant of a doctor' was rated the highest by the students. Conclusion: It is necessary to develop a strategy to improve the social image of the nurse through TV by providing correct information on the nurse's role. For this purpose, it is required to consistently monitor and analyze the nurse's role shown in media.

• 식물분류학회지
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• 제40권2호
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• pp.108-112
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• 2010

제주도에서 발견한 앵초과 참좁쌀풀속에 속하는 신종 탐라까치수염(Lysimachia quelpaertensis K.-H. Tae & J.S. Lee)을 기재 및 도해하였다. 탐라까치수염은 근연종인 까치수염, 진퍼리까치수염, 큰까치수염 및 섬까치수염과는 잎이 윤생하고, 형태가 선형 또는 피침형이며, 화피와 꽃받침이 5장 또는 6장으로 구성된 차이점을 보인다. 탐라까치수염은 참좁쌀풀속 식물종 중에서 잎이 윤생하면서 동시에 백색꽃을 갖는 유일한 종이다.

• 한국산림과학회지
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• 제99권5호
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• pp.736-743
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• 2010

This study examined the ecological attributes of classified forest community by cluster analysis in the mixed forest of Mt. Seokbyung Experimental Forest of Gangwon-Do. The vegetation data were collected in randomly established 51 sample plots (2.04 ha) and analysis adopted the cluster analysis, importance value index, and Shannon's diversity index. Main results were as follows; 1) the study area was classified into 4 clusters (A, B, C and D). 2) The cluster A was dominated by Pinus densiflora with an importance value of 71.6%. The most dominant species in the cluster B and cluster C were Larix leptolepis (57.1%) and Quercus mongolica (40.2%), respectively. Finally, The cluster D was dominated by P. densiflora (30.6%) and Q. mongolica (31.0%) with the mixed forest. 3) In the P. densiflora community (cluster A), distribution of DBH class showed a reverse J-shaped curve. In the L. leptolepis community (cluster B), individuals of dominant species had the bell-shaped distribution. Oak species indicated uniform distribution of DBH class (under 25 cm) in the mixed P. densiflora - Q. mongolica community (cluster D). 4) The species diversity index of the communities in descending order were: Pinus densiflora - Q. mongolica community > Larix leptolepis community > Pinus densiflora community > Quercus mongolica community.

• 대한지구과학교육학회지
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• 제4권3호
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• pp.199-204
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• 2011

This study examines eighteen elementary teachers knowledge and teaching practrice of climate change using the KQEM survey, modified from the survey developed by Leiserowitz, A., Smith, N. & Marlon, J.R. (2010). The survey includes 11 questions from KQEM survey and 2 open ended questions about teachers' knowledge of climate change and their understandings of important climate change concept for elementary students. All of the participant teachers were purposefully selected for the study and were participated in the study volunteerly. The data for this study were analyzed both quantitatively and qualitatively. The result of this study indicates that the teachers have knowledge of climate change specifically about the topics of causes of climate change and consequences of climate change such as shifting biome and ecological impacts. While most of the teachers described climate change phenomena using scientific knowledge, some of the teachers (N=2) showed misconceptions about climate change phenomena. Most of the teachers thought the causes of climate change and potential solutions to reduce climate change are important concept that elementary students need to understand about climate change. Actually, most of the teachers are currently teaching the causes and consequences of climate change (N=13) potential solutions to global warming (N= 8). This study could inform teacher educators about what elementary teachers understand about climate change and what elementary teachers are currently teaching about climate change.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.41.2-41.2
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• 2010

최근 태양전지 제조비용 절감을 위해 초박형 실리콘 태양전지 개발이 활발히 이루어지고 있다. 이에 따라 후면전계(Back Surface Field, BSF) 특성에 대한 관심이 높아지는 추세이다. 이에 본 연구에서는 후면의 결정방향 및 표면구조에 따라 형성되는 후면전계(BSF)의 특성에 대해 알아보고자 하였다. 후면이 절삭손상층 식각(Saw damage etching) 후 (100)면이 드러난 실리콘 기판과 텍스쳐링(Texturing) 후 (111)면이 드러난 실리콘 기판에 후면 전극을 스크린 인쇄 후 Ramp up rate을 달리 하여 소성 공정(RTP system)을 통해 후면전계(BSF)를 형성하여 비교하였다. 후면전계(BSF)의 형상과 특성만을 평가하기 위하여 염산을 이용하여 후면 전극층을 제거하였다. 후면 전극 제거 후 주사전자현미경(Scanning Electron Microscopy)과 3차원 미세형상측정기(Non-contacting optical profiler)로 후면전계(BSF)의 형상을 비교하였다. 또한 후면전계(BSF)의 특성을 평가하고자 Quasi-Steady-State Photo Conductance(QSSPC)를 사용하여 포화전류(Saturation current, $J_0$)을 측정하였고, 면저항 측정기(4-point probe)로 면저항을 측정하여 비교하였다. 후면 전계(BSF)는 (100)면과 (111)면에서 모두 Ramp up rate이 빠를수록 향상된 특성을 보였고, (111)면에서 더 큰 차이를 보였다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권1호
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• pp.221-223
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• 2012

Prostate cancer (CaP) is a common reproductive cancer among men. This study was conducted to correlate the cancer incidence with Gangetic zone and to correlate the tumor marker prostate specific antigen (PSA) level in serum with different age groups and stage of malignancy. Patients suffering from CaP in the pathology unit of Mahavir Cancer Sansthan (Hospital and Research Centre), Patna, Bihar, India were studied from June 2009 to May 2010. PSA level in the serum of CaP patients was estimated by ELISA method. CaP incidence was highly recorded in Gangetic zone than the non-Gangetic zone. Maximum patients were in the 56 - 75 years age group with a marked predominance. Results of PSA examination showed that serum PSA level was not correlating with the age of patient and stage of malignancy. Significantly, elevated level of more than 10 ng/ml of PSA was recorded among the studied cancer patients. In this study, it is concluded that Gangetic zone habitat have high risk of CaP and elevated level of PSA was marked in Bihar, India.

• 한국직업건강간호학회지
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• 제22권3호
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• pp.208-217
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• 2013

Purpose: This study is a correlative study to assess the relationships of fatigue, stress, and burnout among the pregnant nurses in hospital. Methods: The subjects in this study were 103 nurses aged between 22 and 40 who were confirmed as pregnant by the OBGY (Obstetrics and Gynecology) hospital and working at medical facilities located in J-province of G city during the period of July 15 through September 15, 2010. Results: The level of fatigue of pregnant nurses showed an average of 5.60 out of 10 points, and the level of stress showed an average of 25.91. In terms of burnout, the average was 2.72 out of 5 points. The results of the correlative study to assess relationships among fatigue, stress and burnout showed significant positive correlation between burnout and fatigue (r=.47, p<.001) and stress (r=.53, p<.001) and between stress and fatigue (r=.58, p<.001). Therefore, the results show that increased level of fatigue and stress leads to increased level of burnout. Conclusion: The results of the study showed that higher level of fatigue and stress led to higher level of burnout. Therefore, to minimize the burnout of pregnant nurses, many efforts are required in the hospital policy and for the strategies to reduce burnout.

• 말소리와 음성과학
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• 제2권3호
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• pp.165-170
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• 2010

In this study, the most stable portion was identified using 5% moving window during /a/ sustained phonation in normal and pathologic voice signals and the perturbation values were compared between normal and pathologic voices at the mid-point and at the most stable portion using moving window, respectively. The results revealed that some severe pathologic voice signals can be eligible for perturbation analysis by identifying the most stable portion with Err less than 10. In addition, the perturbation acoustic parameters did not differentiate the pathologic voice signals from the normal voice signals when the mid-point was selected to measure the perturbation analysis(p>0.05). However, significantly higher %shimmer and lower SNR values were observed in pathologic voices (p<0.05) when the most stable portion was selected by moving window. In conclusion, moving window could identify the most stable portion objectively which can allow toget the minimum perturbation values (%jitter, %shimmer) and maximum SNR values. Thus, moving window technique can be applicable for more reliable and accurate perturbation acoustic analysis.

• 한국전산유체공학회지
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• 제15권1호
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• pp.71-80
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• 2010

The violent free-surface motions and the corresponding impact loads are numerically simulated by using the Moving Particle Semi-implicit (MPS) method, which was originally proposed by Koshizuka and Oka (1996) for incompressible flows. In the original MPS method, there were several shortcoming including non-optimal source term, gradient and collision models, and search of free-surface particles, which led to less-accurate fluid motions and non-physical pressure fluctuations. In the present study, how those defects can be remedied is illustrated by step-by-step improvements in respective processes of the revised MPS method. The improvement of each step is explained and numerically demonstrated. The numerical results are also compared with the experimental results of Martin and Moyce (1952) for dam-breaking problem. The current numerical results for violent free-surface motions and impact pressures are in good agreement with their experimental data.