• 한국정보과학회논문지:시스템및이론
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• 제32권2호
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• pp.75-84
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• 2005

이 연구는 공간적/시간적 지역성의 효과론 이용하기 위하여 SRAM 버퍼를 사용하는 고성능 NAND-Type 플래쉬 메모리 패키지의 설계에 관한 것이다. 제안된 SRAM 버퍼를 내장한 새로운 NAND형 플래쉬 메모리 패키지 구조는 크게 세 부분으로 구성되어 있다. 즉, 작은 블록 크기의 완전 연관 희생 버퍼(victim buffer)와 큰 블록 크기를 지원하는 완전 연관 공간 버퍼(spatial buffer), 그리고 동적 페칭 유닛(dynamic fetching unit)으로 구성되어 있다. 제안하는 새로운 NAND 형 플래쉬 메모리 패키지는 기존의 NAND형 플래쉬 메모리 구조와 비교할 때 매우 뛰어난 성능 향상 및 저 전력 소비를 이끌어낼 수 있다. 시뮬레이션 결과에 따르면 제안된 NAND 플래쉬 메모리 패키지는 기존의 NAND 플래쉬 메모리와 비교하여 접근 실패율에서는 70%, 평균 메모리 접근 시간에서는 67%의 감소 효과를 보여준다. 더욱이 주어진 크기(e.g., 3KB)의 SRAM 버퍼를 이용한 제안된 패키지는 여덟 배 크기의 직접 사상 버퍼(e.g., 32KB)를 이용한 패키지 및 두 배 크기의 완전 연관 버퍼(e.g., 8KB)를 이용한 패키지보다도 평균 접근 실패율 및 평균 메모리 접근 시간에서 더욱 우수한 성능 향상을 이끌어낼 수 있다.

• 한국대기환경학회지
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• 제26권5호
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• pp.490-498
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• 2010

HCFC-22 (chlorodifluoromethane, $CHClF_2$), one of the major components in various refrigeration, is emitted mostly from developing countries, as its consumption is not limited until 2013 by the Montreal Protocol. In addition, HFC-23 (trifluoromethane, $CHF_3$), a by-product in the manufacture of HCFC-22, is also a powerful greenhouse gas. Here, we discuss the regional emission characteristics of these compounds based on high-frequency in-situ measurements using the "Medusa" GC-MS system. HCFC-22 and HFC-23 baseline concentrations measured at Gosan (Jeju Island, Korea) from November 2007 to December 2008 increased by 1.8 ppt/yr and 0.6 ppt/yr, respectively. Pollution events of these compounds were observed, very frequently (e.g., ~2~3 times) at Gosan than baseline levels. All the measurement data were divided into four groups by simultaneously considering the ratio (HFC-23/HCFC-22) and concentration (HCFC-22) at Trinidad Head (TH, California, USA). The residence time of trajectories were then analyzed in each of the four groups. The results exhibited the existence of a strong correlation with air mass origin for each group: 1) Air masses originating from Siberia in the north and from the Pacific in the south had ratios of 0.08~0.12 and concentrations of 196.9~254.3 ppt which is highly comparable to background air at TH. 2) Air masses passing over the Southern China exhibited similar ratios but higher HCFC-22 concentrations. 3) Air masses passing over the Northern China had ratios of 0.12~0.21. 4) Air masses passing over Korea and/or Japan had ratios of 0.01~0.08. Our results suggest that the HFC-23/HCFC-22 ratio can be used as a good indicator for the assessment of the pollution with Chinese origin. We also confirmed differences in air masses traveling over Northern and Southern China, most likely due to differences in air mass travelling speed over these regions before arriving at Gosan. This signature may be treated as one of the critical components in identifying the emission sources from different parts of China.

• 한국학교ㆍ지역보건교육학회지
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• 제8권2호
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• pp.49-59
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• 2007

Objectives: This study was designed to understand the oral health fact of high school students, search for an education method and learning goal appropriate for the subjects, and utilize them as basic data to think of effective solutions for oral health care. Methods: The samples to achieve the purpose of this research are composed of 386 students in J industrial high school, OO city, Kyounggido, the number of male students 286, and female students 100. Data were statistically analyzed by frequency analysis, cross tabulation by using SPSS WIN Ver. 12.0. Results: First, The answers in terms of oral symptoms were in the order of 31.8% for gum hurt and bleeding, 31.4% for pain in teeth by drinking or eating hot and cold drinks or food, 27.1% for broken or cracked teeth, 25.7% for aching and throbbing teeth, 20.6% for unpleasant mouth smell, and 5.7% for pain of tongue and soft oral tissues. Second, In terms of behavior for oral health, 88.4% answered that they consume cariogenic snacks, while 29.2% of them, 2.5% of male and 6.3% of female enjoy consuming them but hardly brush their teeth after consumption. Third, In terms of timing for brushing teeth, the results show that 50.0% do so before breakfast, 47.9% after breakfast, 15.2% after lunch, 36.9% after dinner, 65.5% before going to sleep, and 3.5% after consuming snacks, whereas 64.2% answered that they are not aware of fluorine mouthwash. Fourth, In terms of oral health condition. proportion of children with one or more caries in permanent teeth was 71.0%, while 51.4% have $2{\sim}3$ cariogenic teeth, and 16.8% have more than 4 cariogenic teeth. Considering sex, female students have somewhat higher ratio showing 68.5% for male and 78.0% for female, but the ratio was 53.1% for male and 46.7% for female in case of $2{\sim}3$ cariogenic teeth, and 17.5% for male and 15.8% for female in case of more than 4 cariogenic teeth. 9.3% of students turned out to have decayed teeth. Fifth, In terms of oral hygiene condition, only 7.9% of them had excellent condition, and 38.4% need to improve. More specifically, 41.1% of male students and 30.6% of female students need to improve their oral hygiene condition. Conclusions: The study results suggest that School Dental health programs increase and need to be community-incorporated and comprehensive from elementary to high school.

• Journal of Chest Surgery
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• 제6권2호
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• pp.131-142
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• 1973

Studies of cardiopulmonary function and acid-base balance were performed on 29 dogs during control period, during oligemic hypotension and following return of blood to the animals. Intravenous morphine and local anesthesia were used. Fifteen of the 29 animals survived the complete experiment. The 14 animals that failed to survive the experimental period died between 15 to 90 minutes after the onset of bleeding. The results were as follows. 1. The heart rate increased after the onset of bleeding and failed to return to control level following reinfusion. Stroke volume decreased markedly after bleeding and failed to recover after return of blood from the reservoir. Cardiac output also decreased during oligemic hypotension and was maintained at this level after re-infusion. Total peripheral resistance decreased significantly immediately after bleeding, however it increased soon over the pre-bleeding level. Central venous pressure decreased after the onset of bleeding and remained at lower level for the rest of the experimental period. Arterial blood pressure, clown to 40-45 mmHg by acute hemorrhage, was elevated near to control level. Left ventricular work decreased tremendously during oligemic hypotension and failed to return to control level with the re-infusion of blood. Hematocrit value showed no significant decrease after bleeding and increased after re-infusion. Hemoglobin decreased after the onset of bleeding and recovered to control value after re-infusion. 2. The respiratory rate fell rapidly after bleeding from 124 to 29 and remained at this lower level for the remainder of the experiment. The tidal volume increased after bleeding and was maintained at this level for the remainder of the experiment. The respiratory minute volume showed no significant changes throughout the experimental period. Oxygen consumption fell lightly in all animals during oligemic hypotension and returned to normal levels following re-infusion. Arterial oxygen content and arterial oxygen saturation decreased following bleeding and the values returned to normal levels after the return of blood from the reservoir The arterio-venous oxygen difference increased after the onset of bleeding. It failed to return to normal values following re-infusion. Arterial $Pco_2$ decreased in all animals after the beginning of the bleeding. Partial pressure of $Co_2$ continued to fall until re-infusion, after which the values returned toward normal. Animals became acidotic. The pH fell to lower level following bleeding. Lactic acid and lactate: pyruvate ratio also increased during same period. Arterial pH and lactic acid failed to return to control value and lactate: pyruvate ratio increased more after re-infusion. Sodium bicarbonate decreased after bleeding and returned to control value following re-infusion.

• 한국자원식물학회지
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• 제22권4호
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• pp.287-292
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• 2009

최근 천연의 의약품과 식품에 대한 관심이 높아지면서 약리성분이 우수하여 수요가 증가하고 있는 겨우살이 [Viscum album var. coloratum(Kom.) Ohwi] 와 겨우살이의 기주식물인 상수리나무(Quercus acutissima Carr.)가지의 조직특성을 조사하고 인공재배 기초 자료로 활용하기 위하여 수행한 결과는 다음과 같다. 겨우살이 종자가 기주목에 부착되면 종자로부터 성장한 흡기가 수피를 뚫고 들어가 형성층 부위에서 왕성한 세포분열을 통하여 여러 갈래로 분지를 형성하며, endophyte가 수피 속에서 성장하다가 일정한 시기가 되면 수피 외부조직으로 발달하여 줄기와 잎으로 성장하였다. 겨우살이 기주목인 상수리나무의 가지는 심재화가 진행되지 않았지만 타일로시스가 부분적으로 발달한 것은 겨우살이 endophyte의 침투영향으로 생각된다. 겨우살이 줄기의 구성세포는 도관상 가도관, 후벽세포, 방사유세포, 축방향유세포로 구성되어 있으며 활엽수로 분류되지만 도관이 분포하지 않았고 도관의 역할을하는 도관상 가도관이 있는 것으로부터 기주목 도관의 벽공과 겨우살이 가도관의 천공부가 결합하는 것으로 생각된다. 겨우살이 줄기의 구성세포 분포비율은 수령이 증가함에 따라 후벽세포의 분포비율이 높았다. 겨우살이 조직은 일반 목본식물에 비하여 유세포의 분포비율이 높고 세포내에 많은 내용물을 포함하고 있었다.

• 한국산학기술학회논문지
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• 제21권11호
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• pp.765-770
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• 2020

터보과급기는 엔진에 장착하여 연비를 개선하는 효과적인 장치로 디젤엔진과 가솔린엔진 모두에서 광범위하게 사용되고 있다. 본 연구에서는 승용차용 가솔린엔진에 장착되는 트윈 스크롤 터빈 터보과급기에서 정상유동의 등엔트로피 터빈 효율을 분석하였다. 자체 설계 제작한 저온 테스트 벤치를 사용하여 정상상태의 압력과 온도, 질량유량을 측정하였다. 테스트 벤치는 공기 압축기, 트윈 스크롤 터빈, 온도 및 압력 측정장치 등으로 구성되었다. 실제 승용차용 엔진에서 주로 사용되는 중저속 엔진 작동 영역에 해당하는 터보과급기 회전속도 60,000 rpm에서 100,000 rpm 의 범위에서 측정을 수행하였다. 이 회전속도 범위에서 등엔트로피 터빈 효율은 0.53에서 0.57의 값을 보였다. 이때 블레이드 속도비은 0.71에서 0.84까지, 팽창비는 1.24에서 1.72의 범위에서 변화하였다. 효율은 블레이드 속도비와 팽창비가 증가하면서 감소하는 경향을 보였다. 그리고 트윈 스크롤 중 스크롤 A 또는 B 만 작동하는 경우에 대한 실험을 수행하여 결과를 스크롤 A와 B 모두 작동할 때와 비교하였다. 60,000 rpm에서는 스크롤 B를 사용한 경우, 그리고 100,000 rpm에서는 스크롤 A를 사용한 경우 높은 효율을 보였다. 따라서 본 연구에 사용한 트윈 스크롤 터빈은 효율적으로 작동하고 있음을 보였다.

• 한국안광학회지
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• 제9권2호
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• pp.257-267
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• 2004

본 연구에서는 전라남도 여수지역의 한 석유화학단지애서 적어도 6개월이상 근무한 작업자 1030명을 대상으로 Lanthony D-15-desaturated 검사법을 이용하여 유기용제노출과 후천적 색각이상간의 연관성을 조사하였다. 작업환경측정은 전 작업시간(8시간) 단시료를 각 작업자에게 부착하는 개인시료를 활용하여 각 개인별 평균, 최대, 누적 연평균 8hr TWA를 산출하였다. 연구결과 연령이 높을수록 색혼란지수(CCI)가 유의하게 높았다(P<0.005). 형태에서는 청황색각이상의 분포가 노출군과 비노출군간에 통계적으로 유의한 수준은 아니었지만, 후천적 색각이상에서 주로 나타나는 제3색형과 제4색형 그리고 복합형이 대부분 노출군에서 높은 분포(비노출군 6.16%, 7.55%, 13.71%, 노출군 5.9%, 7.86%, 14.99%)를 보였다. 마지막으로 색각이상과 관련된 변수들을 보정하였을 때, 후천적 색각이상이 좌안에서는 비노출군과 비교하여 볼 때 통계적 연관성은 없었으나 노출군의 Odds ratio가 증가함을 보였다. 또한 연령에 대하여는 좌 우안에서 모두 높은 통계적 연관성을 보였다(p<0.01). 따라서 이 상의 결과로 근로자가 유기용제 중독으로 인해 초기 신경계이상의 증상으로 후천적 색각이상이 존재할 수 있으므로 안보건 사업에서의 또 하나의 일환으로 근로자의 안보건상태에 대한 지속적인 관심과 관리가 필요하다.

• 한국지역사회생활과학회지
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• 제17권3호
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• pp.143-158
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• 2006

The study examined nutritional conditions to enhance the quality of meals and to provide the basic data for more proper dietary life of college students. Our analysis was based on the body measurement, food intake and food habits for 200 students of Chung-Nam. The nutrient intake was examined using the 24-hour recall method. The data were analyzed by the Computer Aided Nutritional Analysis Program and then the diet quality was estimated using the Mean Adequacy Ratio(MAR), the Nutrient Adequacy Ratio(NAR) and the Index of Nutritional Quality(INQ). The average weight and height of male students were $67.57{\pm}8.66kg,\;174.64{\pm}5.87cm$, while those of female students were $53.46{\pm}6.86kg,\;159.10{\pm}4.19cm$, respectively. The total energy intake of the male students was $3221.71{\pm}200.39kcal$, while that of the female students was $1884.67{\pm}100.93kcal$. The male students are higher than female in % of RDA. The percentages of carbohydrate, protein and lipid for male students were $57.18{\pm}7.83%,\;15.15{\jpm}3.36%\;and\; 27.67{\pm}6.68%$, while those of female students were $58.77{\pm}7.68%,\;15.51{\pm}4.55%\;and\;25.72{\pm}6.20%$, respectively. There was no significant difference in calcium intakes for both groups, however they are less than the RDA. In terms of iron, the male students took $16.98{\pm}5.57mg$ and the female students took $11.35{\pm}2.68mg$, with significant difference (p<0.001). The male and female students showed sufficient intake of vitamins, with significant difference between two groups except for vitamin A. The mean MAR, an index of overall dietary quality, was significantly higher in the male students than female students(p<0.01). Male and female students enjoying two meals or more a day were 59%, and those having enough time for one meal or less a day were 36.5%. Male and female students having no breakfast were 39%. Male and female students having vegetables intake were 53.5%, and having milk or milk products every day were 29.5% of them. In conclusion, nutritional education is recommended to increase the calcium intake and fruit and vegetable consumption for dietary fiber, and to emphasize regularity of meal time.

• 대한지역사회영양학회지
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• 제7권3호
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• pp.293-303
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• 2002

The purpose of this study was to compare dietary attitudes, dietary behaviors and diet qualities of Food and Nutrition major and non-major female student at a university located in Inchon. The subjects included 74 female Food and Nutrition and majors and 45 non-Food and Nutrition major female university students. This cross-sectional survey was conducted using a self-administered questionnaire, and the data were analyzed by a SPSS 10.0 program. The nutrient intake data collected from Three-day recalls were analysed by the Computer Aided Nutritional Analysis Program and then the diet quality was estimated using the Mean Adequacy Ratio (MAR), the Nutrient Adequacy patio (NAR) and the Index of Nutritional Quality (INQ). There was no significant difference in dietary behaviors between Food and Nutrition majors and non-majors. However, most of the female university students had poor eating habits, such as overeating, unbalanced meals, and skipping of meals. In particular, more than 50% of the female university students skipped breakfast. As for weighing themselves once a week, changing dietary lifestyles, calculating food calories and having interest in information on nutrition on health, the ratio of Food and Nutrition majors was significantly higher as compared to that of the non-majors. There was a significant difference in food consumption frequency except for mick and milk products, and iron-rich foods between the Food and Nutrition majors and non-majors. However, there was a significant difference in the frequency scores of iron-rich floods between the Food and Nutrition majors and non-majors. The MAR of Food and Nutrition majors and non-majors were 0.80$\pm$0.13, 0.79$\pm$0.13, respectively. However, in the Food and Nutrition majors and non-majors, the NARs of calcium were 0.61$\pm$0.21 and 0.59 $\pm$ 0.20, and that of iron were 0.61$\pm$0.21 and 0.59$\pm$0.16, respectively, which was extremely low when compared to that of the other nutrients. This result was similar to that of the INQ. Therefore, nutritional education is necessary if female university students are to practice optimal nutrition, including well-balanced diets and eating foods of high nutritional quality.

• 한국작물학회지
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• 제33권3호
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• pp.287-291
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• 1988

1981년 전남지방에서 생산된 쌀보리 '영산보리'를 공시하여 일반보리쌀은 농업기술연구소에 설치되어 있는 표준도정시설로, 할맥은 맥류연구소에서 확립된 할맥가공방법으로 가공하여 도정수율, 입형, 소요전력, 화학성분 그리고 취반특성을 구명한 결과는 다음과 같다. 1. 도정율은 일반보리쌀이 70.10%인데 비하여 할맥이 68.27% 였다. 2. 입장/입폭비율은 할맥이 2.88인데 일반보리 쌀이 1.36이었으며 천립중은 할맥이 9.5g인데 일반보리쌀이 18.5 g 이었다. 3. 가공중 소요전력은 일반보리쌀이 91.1 kW/1.000kg인데 비하여 할맥이 105.1 kw/1,000 kg 으로 할맥가공에서 140.0kW/1,000 kg 더 많이 소요되었다. 4. 단백질, MgO 함량은 할맥이 일반보리쌀에서 보다 높았으나, P$_2$O$_{5}$, $K_2$O 및 Mn은 거의 차가 없었다. 5. 취반후 백도의 차이는 일반보리쌀이 45.5%, 할맥이 49.5%, 수분흡수율은 일반보리쌀이 225.7%, 할맥이 312.7 %, 팽윤성은 일반보리쌀이 283%, 할맥이 318%로 할맥이 일반보리쌀보다 각각 4.0, 87.0 및 35% 높았다.및 35% 높았다.