• KIEAE Journal
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• 제14권1호
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• pp.75-81
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• 2014

This study aims at investigating the benefit of actively controlling humidity to improve thermal comfort and energy efficiency in climate zones other than hot-dry. For this research purpose, three thermal control strategies, which adopted different initiative degrees in humidity control, were developed - i) temperature controls, ii) temperature and humidity controls, and iii) thermal sensation controls. Performance of the developed strategies were experimentally tested in a full scale mock up of an office environment. The study revealed that air temperature was better controlled in the occupied zone under the first two strategies than the thermal sensation based strategy. On the other hand, the thermal sensation-based strategy maintained thermal sensation levels more comfortably. In addition, energy consumption was significantly reduced when humidity was actively controlled for thermal comfort. The thermal sensation-based control strategy consumed significantly less electricity than the first two strategies. From these findings, this study indicated that adoption of an active humidity control system based on thermal sensation can provide increased thermal comfort as well as energy savings for summer seasons in climatic zones other than hot-dry.

• Journal of Magnetics
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• 제20권4호
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• pp.331-335
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• 2015

The ferromagnetic and electronic structure for the $Al_xGa_{1-x}P$ and Mn-doped $AlGaP_2$ was studied by using the self-consistent full-potential linear muffin-tin orbital method. The lattice parameters of un-doped $Al_xGa_{1-x}P$ (x = 0.25, 0.5, and 0.75) were optimized. The band-structure and the density of states of Mn-doped $AlGaP_2$ with or without the vacancy were investigated in detail. The P-3p states at the Fermi level dominate rather than the other states. Thus a strong interaction between the Mn-3d and P-3p states is formed. The ferromagnetic ordering of dopant Mn with high magnetic moment is induced due to the (Mn-3d)-(P-3p)-(Mn-3d) hybridization, which is attributed by the partially filled P-3p bands. The holes are mediated with keeping their 3d-characters, therefore the ferromagnetic state is stabilized by this double-exchange mechanism.

• 플랜트 저널
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• 제4권3호
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• pp.60-65
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• 2008

Power plant industry has been developed at high-capacity, high-technology, and innovation. Steam turbine became the most useful equipment that dominate more than 50% of all the world electricity production. And developed new materials of the turbine blade and extended length of the turbine last blade brought reform in steam turbine performance upgrade. In this paper, when do partial load driving in high-capacity steam turbine, optimum driving method found whether there is something. In operating steam turbine, there is a lot of loss from secondary wake and throttle of the 1st stage nozzle by the biggest leading factor that load fluctuation affects in high-pressure steam turbine performance. Effect of internal efficiency by 1 stage nozzle is the biggest here, but here fluid flow and flow analysis were not yet examined closely definitely. So, Analyzed design data and acceptance performance test result to applying subcritical pressure drum type 560 MW, supercritical-pressure once through type 500 MW, and 800 MW steam turbines actually. In conclusion, at partial load driving, partial arc admission(PAA) is more efficient than full arc admission(FAA) efficiency. This is judged by because increase being proportional with gross energy of stream that is pressure - available energy if pressure of stream that is flowed in to the turbine increases, available energy becomes maximum and turbine efficiency improves. Therefore, turbine performance is that preview that first stage performance fell if decline is serious in partial load because first stage performance changes according to load.

• 천문학논총
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• 제35권1호
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• pp.1-16
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• 2020

We report a calendar sheet for the 31st year of the reign of King Gojong (1894) (hereafter, calendar sheet 1894) in Korea, which calendrical data in a single page. This calendar sheet 1894 is composed of 14 rows by 14 columns (about 190 cells), and various calendrical data are recorded such as the sexagenary circle of the first day in each month, 24 solar terms, full moon day. In this paper, we compare calendrical data of 1894 calendar sheet with those of the almanac based on the Shixian calendar (hereafter, annual almanac) of the same year. Our findings are as follows. First, we find that the year is expressed using the reign-year of the king of the Joseon dynasty differently from using the reign-style of China in the annual almanac those times. Other calendar days of this calendar sheet are the same as those of the annual almanac in term of lunar dates, 24 solar terms, sexagenary days and so forth. Second, we find that the calendar sheet 1894 contains memorial days for 64 lineally ancestors of the Joseon royal family. These royal memorial days appears in the annual almanac two years later (i.e., 1896). Third, as the most distinctive feature, we find that the symbol of 工 kept every two cells. It was found that the cells can be filled with three days as the maximum number of days and then are labelled the same symbol 工 every second cell. This feature allows us to get the first year in which this kind of calendar sheet was published. It is conjectured one of 11 years, such as 1845, 1846, 1847, 1873, 1874, 1875, 1876, 1877, 1878, 1879 or 1880. We also think that the format of the calendar sheet 1894 has influenced on the Daehan-Minryeok (Korean civil calendar sheet) of 1920.

• 한국보육지원학회지
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• 제8권2호
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• pp.121-137
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• 2012

본 연구는 서울시와 경기도 소재 종일제 어린이집에 다니는 243명 유아의 어머니를 대상으로 양육죄책감과 양육스트레스가 양육태도에 미치는 영향을 파악하고자 했다. 연구의 자료분석은 SPSS 17.0 for Window를 이용하여 실시하였으며, t-test, Pearson 상관분석, 위계적 회귀분석을 실시하였다. 그 결과 첫째, 모학력과 모취업유무에 따른 어머니의 양육죄책감, 양육스트레스 및 양육태도의 차이로는, 전문대졸 이하의 학력인 어머니보다 대졸 이상의 학력인 어머니의 부정적 양육태도가 높고, 취업모가 비취업모보다 긍정적 양육태도가 더 높게 나타났다. 둘째, 어머니의 양육죄책감과 양육스트레스는 어머니의 긍정적 양육태도와는 부적 상관관계가 있는 것으로 나타났고, 부정적 양육태도와는 정적 상관관계가 있는 것으로 나타났다. 셋째, 어머니의 긍정적 양육태도와 부정적 양육태도에 가장 큰 영향력을 미치는 변인은 양육죄책감으로 나타났다.

• 한국멀티미디어학회논문지
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• 제8권7호
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• pp.889-897
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• 2005

본 논문에서는 다중 참조영상에 적용을 위한 고속 움직임 추정 (motion estimation) 알고리즘을 제안한다. 우선 전역움직임추정방법(full search)의 고속 알고리즘인 연속 제거 알고리즘(successive elimination algorithm)을 다중 참조영상(multi-reference frames)에 적용하였을 때의 결과를 분석하고, 이를 바탕으로 계산량 감축 방안을 제안한다. 제안된 방법은 바로 이전 영상에 대한 움직임 벡터를 연속 제거 알고리즘을 적용하여 추출하고, 그 외의 참조영상에 대해서는 이전 영상에서 얻어진 움직임 벡터를 기반으로 외삽(extrapolation)을 수행함으로써 추정한다. 이 추정된 벡터를 중심으로 탐색범위를 적응적으로 제한함으로써 화질 저하를 최소화시키면서 계산량을 크게 감축하도록 제안하였다. 실험을 통해 제안된 방법의 성능을 분석하고 검증하였다.

• Journal of Yeungnam Medical Science
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• 제13권2호
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• pp.251-260
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• 1996

To evaluate the effect of low lactose special formula (MF-1) for the treatment of acute diarrhea, we studied thirty nine infants who were admitted with acute diarrhea to the Department of Pediatics, Yeungnam University Hospital. 39 infants of under 6 months of age who had been fed on formula feeds were randomly allocated to receive either a diluted regular formula milk or a low lactose special formula. Each infant received intravenous rehydration during fasting for 6-12 hours. Group 1 (n=15) was fed half strength of regular formula (80-100cc/kg/day) for the first 24 hours, three quarters strength formula (100-120cc/kg/day) for the next 24 hours, and continued feeding with the full strength regular formula milk. Group 2 (n=24), who fed the same amount of milk as Group 1, continued feeding with the full strength low lactose special formula from the start of feeding. Male to female sex ratio was 1.6 to 1. The characteristics of infants on admission were comparable in the age, the duration of diarrhea and the stool frequency before admission, the degree of dehydration. There were no significant differences in the duration of hospitalization, changes in stool weight and stool frequency after admission between two groups.(p>0.05) The Body weight and skin fold thickness were increased in group 2 who fed low lactose formula, but those who fed diluted regular formula showed reduction of body weight and skin fold thickness ($64.2{\pm}51.4g$ vs $-11.4{\pm}52.2g$, $0.6{\pm}0.8mm$ vs $-0.1{\pm}0.3mm$ respectively) during hospitalization. (p<0.05) We conclude that low lactose special formula milk can be recommended instead of diluted regular formula for acute diarrhea treatment in infants.

• 한국비블리아학회지
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• 제24권3호
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• pp.99-120
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• 2013

본 연구는 다른 직업과 비교하여 사서직의 현 단계의 직업지표(상황)와 10년 후의 직업지표(전망)에 대한 인식을 분석하여 문제점을 파악, 개선방안을 제시하기 위해 수행되었다. 문헌정보학 전공 학생과 사서를 대상으로 조사 분석한 결과, 현재와 10년 후 전망 모두 임금 수준이 타 직업보다 낮고, 일자리수요도 낮다고 생각하는 것으로 파악되었다. 또 학생과(58.4%) 사서(64.2%) 모두 과반 이상이 정규고용이 낮다고 생각하고, 직장이동 가능성 또한 낮다고 생각하는 것으로 파악되었다. 본 연구에서는 이 같은 분석결과 등을 토대로 첫째 사서직의 저임금 문제를 해소하기 위해 비정규직을 정규직화 할 것, 둘째 사서직의 취업진로 확대를 위해 인구 5만 명당 공공도서관 1개관 시대를 조기에 열 것, 셋째 공공도서관의 위탁운영 및 BTL 사업화를 철회할 것 등을 제안하였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제3권3호
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• pp.208-215
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• 2011

A full-scale field trial in ice-covered sea is one of the most important tasks in the design of icebreaking ships. The first Korean icebreaking research vessel 'ARAON', after her delivery in late 2009, had a sea ice field trial in the Arctic Sea during July-August, 2010. This paper describes the test procedures and data analysis on the icebreaking performance of the IBRV ARAON. The data gathered from the icebreaking performance test in the Chukchi Sea and the Beaufort Sea during the Arctic voyage of ARAON includes the speed and engine power of the ship as well as sea ice thickness and strength data. The air temperature, wind speed and heading of the ship were also measured during each sea ice trial. The ARAON was designed to break 1 m thick level ice with a flexural strength of 630kPa at a continuous speed of 3knots. She is registered as a KR POLAR 10 class ship. The principal dimensions of ARAON are 110 m, 19 m and 6.8 m in length, breadth and draft respectively. She is equipped with four 3,500kW diesel-electric main engines and two Azipod type propulsion motors. Four sea ice trials were carried out to understand the relationship between the engine power and the ship speed, given the Arctic ice condition. The analysis shows that the ARAON was able to operate at 1.5knots in a 2.5m thick medium ice floe condition with the engine power of 5MW, and the speed reached 3.1 knots at the same ice floe condition when the power increased to 6.6MW. She showed a good performance of speed in medium ice floe compared to the speed performance in level ice. More detailed analysis is summarized in this paper.

• Korean Journal of Radiology
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• 제22권3호
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• pp.297-307
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• 2021

Objective: To compare the performance of simulated abbreviated breast MRI (AB-MRI) and full diagnostic (FD)-MRI in distinguishing between benign and malignant lesions detected by MRI and investigate the features of discrepant lesions of the two protocols. Materials and Methods: An AB-MRI set with single first postcontrast images was retrospectively obtained from an FD-MRI cohort of 111 lesions (34 malignant, 77 benign) detected by contralateral breast MRI in 111 women (mean age, 49.8. ± 9.8; range, 28-75 years) with recently diagnosed breast cancer. Five blinded readers independently classified the likelihood of malignancy using Breast Imaging Reporting and Data System assessments. McNemar tests and area under the receiver operating characteristic curve (AUC) analyses were performed. The imaging and pathologic features of the discrepant lesions of the two protocols were analyzed. Results: The sensitivity of AB-MRI for lesion characterization tended to be lower than that of FD-MRI for all readers (58.8-82.4% vs. 79.4-100%), although the findings of only two readers were significantly different (p < 0.05). The specificity of AB-MRI for lesion characterization was higher than that of FD-MRI for 80% of readers (39.0-74.0% vs. 19.5-45.5%, p ≤ 0.001). The AUC of AB-MRI was comparable to that of FD-MRI for all readers (p > 0.05). Fifteen percent (5/34) of the cancers were false-negatives on AB-MRI. More suspicious margins or internal enhancement on the delayed phase images were related to the discrepancies. Conclusion: The overall performance of AB-MRI was similar to that of FD-MRI in distinguishing between benign and malignant lesions. AB-MRI showed lower sensitivity and higher specificity than FD-MRI, as 15% of the cancers were misclassified compared to FD-MRI.