• 한국지구과학회지
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• 제37권6호
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• pp.359-372
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• 2016

The time-series of Walker circulation index (WCI) in this study shows the strengthening of the Walker circulation in recent years. To further understand the large-scale features related to the WCI strengthening, a difference between the averaged meteorological variables in two time periods 1999-2013 and 1984-1998 is analyzed. The difference in 850 hPa stream flows between the two periods shows that the anomalous easterlies (anomalous trade wind) are dominant due to the strengthening of anomalous anticyclonic circulations at the subtropical Pacific of both hemispheres. The difference between the averaged zonal atmospheric circulations over $5^oS-5^oN$ in the two periods confirms that upward flows are strengthened at the tropical western Pacific and downward flows are strengthened at the tropical central and eastern Pacific in recent years. It matches the WCI strengthening in recent years. The time-series of tropical cyclone (TC) genesis frequency from July to September shows that a mean TC genesis frequency from 1999-2013 decreases compared to that of the time period 1984-1998. The monsoon trough in the period 1984-1998 was located in the further east direction and stronger than that in the period 1999-2013. TCs in the recent period that are generated in further west than TCs in the past period moved from the west. Thus, the TC intensity along the coasts in East Asia becomes weaker in recent period. The intensification of Walker circulation in recent years is related to the weaker TC intensity in East Asia through strengthened anomalous anticyclones at the subtropical western Pacific.

• 대한가정학회지
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• 제19권3호
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• pp.41-45
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• 1981

This study was carried out to observe the changes of Vitamin C content and to preserve the quality for the circulation periods of hot green pepper fruits wrapped with polyethylene film under the indoor temperature, as well as to find the proper time for harvest of hot green pepper fruits as a hot taste food and vegetable. the results obstained were as follows: 1. The consignment rate of hot green pepper fruits was highest, 60.2% on the 25th day after flowering, the nest 25.4% on the 20 th day, 10.3% on the 30th day and 4.1% on the 35th day. 2. the content of Vitamin C I each pepper fruits was highest o the 30th day, considerably high on the 25th day and 20th day. 3. The total content of Vitamin C in each part of hot green pepper fruits; the content in pericarp was much higher than in placenta and seed, and that of hydro type Vitamin C was almost the same. 4. The reduction rate of vitamin C during circulation periods was highest on the 3rd day; 42% in pericarp, 50% in placenta, 65% in seed. But in the package wrapped up with polyethylene film, the reduction rate in the same period was 5% in pericarp, which was very low in reduction, and those in placenta and seed were almost the same as in the unwrapped state.

• 한국비블리아학회지
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• 제4권1호
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• pp.103-127
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• 1980

Due to the rapid growth of publications, librarians have been facing the problems caused by the shortage of stack as well as the quality deterioration of library collections. This naturally disappointed the user communities and the present library activities are weak and inadequate. It seems to the author that one of the desirable actions in remedying this problems is to weed library collections properly and regulraly. The purpose of this study is to establish weeding criteria in library collections, particulary in the fields of polictical science, economics and law In order to establish weeding criteria, shelf-time period which is the length of time that a book remains on the shelf between the last two users of a volume, was measured by examining the book cards or date-due slips of circulating books and collections which remained in the stack. The results of this study are as follows: (1) In the fields of political science economics and law, the shelf-time periods of general materials in Korean for circulation was measured. (2) This study shows shelf-time periods that vary in different subject fields. (3) Combining the shelf-time periods of books in active circulation and the total collection including books which have never been circulated, the size of library holdings which may satisfy a certain percentage of the current circulation can be estimated.

• Journal of Chest Surgery
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• 제25권3호
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• pp.240-246
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• 1992

The effects of extracorporeal circulation on plateler count were studied in 120 patients. We measured platelet count before, during, after extracorporeal circulation, and postoperative 0, 1, 3, 5, 7, 9, 11th days to evaluate the effects of total extracorporeal circulation time and types of oxygenator on changes of platelet count The patients were classified into group I [extracorporeal circulation time < 100 minutes, 45 patients], II [100 < extracorporeal circulation time < 200 minutes, 48 patients], III [extracorporeal circulation time >200 minutes, 27 patients], and also all patients were classified into group B [bubble oxygenator, 84 patients] and group M [membrane oxygenator, 36 patients]. The group I, II, III were subclassified into IB, IM, IIB, IIM, IIIB and IIIM according to the types of oxygenator. The results were as follows: 1. The platelet counts were reduced throughout extracorporeal circulation and in the early postoperative periods upto postoperative third day. 2. The platelet counts after postoperative 9th to 11th day increased significantly compared with those of preoperative levels. 3. After extracorporeal circulation, the platelet recovered gradually in all groups, especially faster in group I compared with those of group II and III. 4. The effect of the type of oxygenator on the recovery of platelet count was not significant. In conclusion, extracorporeal circulation time influenced the change of platelet count. Therefore, in order to prevent of decrease of platelet count associated with extracorporeal circulation time, the extracorporeal circulation time should be shortened.

• 암석학회지
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• 제23권3호
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• pp.249-259
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• 2014

해수의 순환이 지구표면의 열 분배 및 궤도함수주기와 천년주기의 기후변화와 밀접한 관계가 있음이 알려지면서 과거 해수의 흐름을 지시할 수 있는 지시자의 개발이 관심을 끌고 있다. 이 논평에서는 해수 자생성 네오디뮴 동위원소 비를 해수순환의 지시자로 활용하는 원리와 분석방법 그리고 두 가지 적용사례를 소개한다. 먼저 지난 빙하기-간빙기와 아빙기-아간빙기에 걸쳐 북대서양심층수 세기의 변화를 명확히 볼 수 있는 예를 소개한다. 다음으로는 북극해에서 담수의 유입과 해수순환을 재구성한 예를 보인다.

• 한국문헌정보학회지
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• 제56권4호
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• pp.357-376
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• 2022

본 연구에서는 2019년부터 2021년까지 3년의 기간 동안 A 공공도서관의 대출 현황 및 대출 추이를 분석하였다. 조사 결과, 코로나 전기와 코로나 시기 간, 코로나 시기와 코로나 회복기 간에는 대출 빈도 평균 차이가 유의미한 것으로 나타났다. 그러나, 코로나 전기와 코로나 회복기 간에는 대출량 평균 차이가 유의미하지 않는 것으로 나타났다. 3년을 통합해서 분석한 결과, 월별, 요일별, 시간대별 대출 빈도의 분포에 있어서 유의한 차이가 있는 것으로 나타났다. 시기별로 세부 비교한 결과, 코로나 전기와 코로나 회복기의 월별. 시간대별 대출 분포가 유사하며, 코로나 시기의 월별, 시간대별 대출 분포는 코로나 전기 및 코로나 회복기와 상이한 것으로 나타났다. 코로나 시대 장기간의 공공도서 관 대출 추이에 대해 조사한 본 연구의 결과는 향후 공공도서관의 장서 개발, 서비스 운영 및 개선에 활용되고, 공공도서관 이용자들의 대출 행태와 정보 요구를 예측하는데 활용될 수 있을 것으로 기대된다.

• 한국식품저장유통학회지
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• 제1권1호
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• pp.45-53
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• 1994

Circulation state and changes in quality during ripening of strawberry were investigated. Tissue damage of the fruit happened when it was harvested and selected. Strawberry has been harvested without considering of fruit temperature in the farm. It takes 25 hours from Goreung which is main production area of strawberry to retailer, and seasonal variation in the price was severe. Shelf-life of strawberry from Feb to Mar was 5-6 days, and was 24-30 hours from May to June. Desirable ripening stage was 28-30th day after blooming and 40th day and after this was over ripening stage when the degree of ripening estimated by color "a" value and color saturation. Overall eating quality and vitamin C contents and sugar content were more higher in the fruit of the desirable ripening stage than that of unripening and over ripening stage. The dark redness degree was high in the over ripening stage.

• 한국해양학회지:바다
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• 제29권2호
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• pp.101-115
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• 2024

해양의 고수온 현상은 지구온난화로 인한 주요 문제 중 하나로, 식량 자원의 감소와 해양 탄소 흡수력의 저하 등, 해양 생태계와 인류에게 직접적인 위협으로 부상하고 있다. 따라서, 한반도 주변 해역에서의 고수온 예측은 해양 환경 모니터링 및 관리에 중요하다. 본 연구에서는 역학 모델 기반 한반도 고수온 예측 시스템의 성긴 해양의 수직격자체계로 인한 고수온 예측의 과소모의를 개선하기 위해 LSTM 모델을 개발하였다. 2023년에 대해 수행된 한반도 고수온 예측 시스템의 고수온 예측 결과와 LSTM 모델의 결과를 기반으로 한반도 주변의 동해 해역, 황해 해역 그리고 남해 해역에서의 고수온 예측 성능을 평가했다. 본 연구에서 개발된 LSTM 모델이 세 영역 모두에서 수온이 상승하는 시기에 수온 예측 성능을 크게 개선하는 것으로 나타났으며, 수온 상승이 시작되기 전이나 하강하는 시기에는 예측 성능의 개선 효과가 미미했다. 이는 LSTM 모델이 성층이 강화되는 환경에서 성긴 수직격자로 인해 발생하는 고수온 예측의 과소모의를 개선할 수 있는 가능성을 보여준다. 향후 역학 모델의 예측 성능 개선이나 역학 모델의 대체에 자료기반 인공지능 모델의 활용성이 확대될 것으로 기대한다.

• 대기
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• 제23권4호
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• pp.377-387
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• 2013

Projections of changes in the low latitude atmospheric circulation under global warming are investigated using the results of the CMIP5 ensemble mean. For this purpose, 30-yr periods for the present day (1971~2000) and the end of the $21^{st}$ century (2071~2100) according to the RCP emission scenarios are compared. The wintertime subtropical jet is projected to strengthen on the upper side of the jet due to increase in meridional temperature gradient induced by warming in the tropical upper-troposphere and cooling in the stratosphere except for the RCP2.6. It is also found that a strengthening of the upper side of the wintertime subtropical jet in the RCP2.6 due to tropical upper-tropospheric warmings. Model-based projection shows a weakening of the mean intensity of the Hadley cell, an upward shift of cell, and poleward shift of the Hadley circulation for the winter cell in both hemispheres. A weakening of the Walker circulation, which is one of the most robust atmospheric responses to global warming, is also projected. These results are consistent with findings in the previous studies based on CMIP3 data sets. A weakening of the Walker circulation is accompanied with decrease (increase) in precipitation over the Indo-Pacific warm pool region (the equatorial central and east Pacific). In addition, model simulation shows a decrease in precipitation over subtropical regions where the descending branch of the winter Hadley cell in both hemispheres is strengthened.

• 한국관광식음료학회지:관광식음료경영연구
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• 제15권2호
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• pp.57-72
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• 2004

This study is carried out to investigate the effect of any periods in the freezer and the product of value, moisture content, baking loss, specific volume loaf in manufncturing process thereof. The moisture content of the croissant slightly decreased as the periods passed in the freezer. And as passed periods frozen croissant dough dried naturally by the freezer fan. 1. As frozen periods passed croissant dough decreased moisture content and loaf volume. The volume is relation to the molsture content and croissant dough' gluten. Yeast is active but croissant dough is dried so pastry margarine's moisture vaporized little by little. 2. 1 day frozen bench time provided maximum specific loaf volume while croissant shape was unsettled, moisture content was highest. At the same dough croissant hardness had very sofi crust. 3. 1week and 2weets frozen dough had specific loaf volume and hardness with proper crust color. As the proper bench time provided best shape of croissant, color. 4. 4weeks and 8weeks frozen dough had over-al] value of croissant accelerating older product. As the same result, over Sweets frozen periods product were not available for sale and serving to customers. 5. By the sensory evaluation tests, over-all croissant as 1 week, 2weeks were significantly higher quality those than 6. 1day, 4weeks and 8weeks. Textural properties of croissant over 4weeks frozen periods so hard for every panel. According to the study, not croissant dough but also any other frozen dough(ex.Danish, brioche etc.)have to need proper bench time and 1week or 2weeks circulation making method have to given encouragement to practical pastry industry. Add to this study using only for frozen dough yeast instead of using fresh and instant