• 제목/요약/키워드: Abnormal cooling

검색결과 39건 처리시간 0.021초

1982-1983년.1997-1998년 엘니뇨현상 전후 한국동해역에서의 이상 저수온 현상 (Abnormal Cooling before and after the 1982-1983 and 1997-1998 ENSO Events in the Korean East Sea Water)

  • 홍철훈
    • 한국수산과학회지
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    • 제41권4호
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    • pp.294-300
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    • 2008
  • Abnormal cooling of the Korean East Sea Water(KESW) in the East Sea before and after the 1982-1983 and 1997-1998 ENSO events is examined using bimonthly routine observation data from the National Fisheries Research and Development Institute of Korea for the period 1965 to 2002. The KESW, which occupies roughly a region between the Korean Peninsula and west of approximately $131^{\circ}E$, showed extreme cold-state years(1981 and 1996) prior to the two strongest ENSO events of the last half-century. Inter-annual bimonthly mean anomalies at 100 m in the KESW region were $-3.10^{\circ}C\;and\;-3.41^{\circ}C(SD=1.4^{\circ}C)$ in 1981 and 1996, respectively. These results suggest that extreme cooling of the KESW may be a prelude to very strong ENSO events through large-scale teleconnections.

Predictive factors of death in neonates with hypoxic-ischemic encephalopathy receiving selective head cooling

  • Basiri, Behnaz;Sabzehei, Mohammadkazem;Sabahi, Mohammadmahdi
    • Clinical and Experimental Pediatrics
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    • 제64권4호
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    • pp.180-187
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    • 2021
  • Background: Severe perinatal asphyxia results in multiple organ involvement, neonate hospitalization, and eventual death. Purpose: This study aimed to investigate the predictive factors of death in newborns with hypoxic-ischemic encephalopathy (HIE) receiving selective head cooling. Methods: This cross-sectional descriptive-retrospective study was conducted from 2013 to 2018 in Fatemieh Hospital of Hamadan and included 51 newborns who were admitted to the neonatal intensive care unit with a diagnosis of HIE. Selective head cooling for patients with moderate to severe HIE began within 6 hours of birth and continued for 72 hours. The required data for the predictive factors of death were extracted from the patients' medical files, recorded on a premade form, and analyzed using SPSS ver. 16. Results: Of the 51 neonates with moderate to severe HIE who were treated with selective head cooling, 16 (31%) died. There were significant relationships between death and the need for advanced neonatal resuscitation (P=0.002), need for mechanical ventilation (P=0.016), 1-minute Apgar score (P=0.040), and severely abnormal amplitude-integrated electroencephalography (a-EEG) (P=0.047). Multiple regression of variables or data showed that the need for advanced neonatal resuscitation was an independent predictive factor of death (P=0.0075) and severely abnormal a-EEG was an independent predictive factor of asphyxia severity (P=0.0001). Conclusion: All cases of neonatal death in our study were severe HIE (stage 3). Advanced neonatal resuscitation was an independent predictor of death, while a severely abnormal a-EEG was an independent predictor of asphyxia severity in infants with HIE.

1981年 夏季 東海沿岸域의 異常底水溫現象 (On the Abnormal Cooling Phenomenon in the Coastal Areas of East Sea of Korea in Summer,1981)

  • 홍철훈;조규대;양성기
    • 한국해양학회지
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    • 제19권1호
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    • pp.11-17
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    • 1984
  • 1981년 7월 7일~12일 기간중 동해에서의 해양관측 결과와 국립수산진흥원 (1961~1981년) 및 일본 기상청 자료(1975, 1981년)를 분석한 결과, 1981년 하계의 1$0^{\circ}C$ 등온선이 130 E선의 35 30 N 이남 해역에서 약 75m 이심에 나타났으나 이 이북 해역에서부터 20~30m로 급격히 상승했다. 한편, 1966~1981년의 130 E선 에서 35 N~37 30 N의 3정점의 깊이 100m의 수온표준편차는 2~4$^{\circ}C$로서 변동폭이 매우 컸다. 1981년 하계의 수온 편차는 표준 편자의 1.5배 이상이며, 수심 150m 이천은 평년에 비해 5~1$0^{\circ}C$ 낮았다. 특히 1$0^{\circ}C$ 등온선이 평년보다 20~120마일 남하하여 35 N~36 N 해역에 까지 이르렀다. 이상의 결과를 종합해 볼 때 1981년은 약 15년 (1966~1981년) 동안에 처음 있는 이상 저수온년이었다.

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5% Rule Disclosure and Stock Trading Volume : Evidence from Korea

  • KIM, Eung-Gil;KIM, Sook-Min
    • The Journal of Asian Finance, Economics and Business
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    • 제6권4호
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    • pp.297-307
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    • 2019
  • Despite the fact that the implementation of 5% rule is widely recognized to enhance the transparency of capital market and fairness of corporate governance market, a few evidences present information effect of 5% rule. Using 7,088 non-financial firm-year observations listed on the Korea Stock Exchange from 2006 to 2012, we analyze the relation between trading volume and 5% rule disclosure. The results show that the daily and abnormal trading volume is increased when 5% rule disclosure is released. Moreover, the trading volume is significantly increased during cooling period. Specifically, trading volume is significantly greater when one day before cooling period or the expiration day of cooling period. We also find the information effect of firms with stable ownership structure before 5% rule disclosure is relatively smaller than the firms with unstable ownership structure with unstable ownership structure. These results imply that capital market participants use the information from 5% rule disclosure and reflect in their real economic decision.

Containment Closure Time Following Loss of Cooling Under Shutdown Conditions of YGN Units 3&4

  • Seul, Kwang-Won;Bang, Toung-Seok;Kim, Se-Won;Kim, Hho-Jung
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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    • pp.647-652
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    • 1998
  • The YGN Units 3&4 plant conditions during shutdown operation were reviewed to identified the possible even scenarios following the loss of shutdown cooling. The Thermal hydraulic analyses were performed for the five cases of RCS configurations under the worst event scenario, unavailable secondary cooling and no RCS inventory makeup, using the RELAP5/MOD3.2 code to investigate the plant behavior, From the analyses results, times to boil, times to core uncovery and times to core heat up were estimated to determined the containment closure time to prevent the uncontrolled released of fission products to atmosphere, These data provide useful information to the abnormal procedure to cope with event.

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천연가스냉방의 경제성 분석 연구 (A Study on Economic Analysis of Natural Gas Cooling)

  • 김기호
    • 한국가스학회지
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    • 제17권1호
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    • pp.42-48
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    • 2013
  • 한반도의 지구 온난화는 세계에서 가장 빠른 속도로 진행되고 있고, 이상기후 현상도 날로 심화되고 있다. 따라서 하절기의 혹서와 동절기의 혹한으로 인한 전력수요가 급증함에 따라 우리나라의 전력 수급상황은 매우 어려운 상황에 있다. 현재 천연가스는 현존하는 화석연료 중 온실가스 배출이 가장 적어서 공급이 확산되고 있다. 천연가스냉방은 전력피크 완화는 물론, 발전소 추가 건설비용의 절감, 천연가스 저장설비의 효율적 운영 및 분산형 전원으로서의 역할수행도 가능한 장점이 있다. 따라서 본 연구는 전력 부하관리의 대안으로서 천연가스냉방의 경제성을 분석하였다.

CuO 첨가에 따른 $Y_3$Fe$_5$O$_{12}$ 소결체의 미세구조 변화 (Dependence of Microstructure of Sintered $Y_3$Fe$_5$O$_{12}$ in Addition of CuO)

  • 이재동;김광석;김성재;김태옥
    • 한국세라믹학회지
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    • 제35권10호
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    • pp.1014-1019
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    • 1998
  • As results of the study on the sinterbility of YIG at the low temperature using CuO as additive CuO com-pound which contain {{{{ { {Fe }_{2 }O }_{3 } }} was shown liquid in sintering process. YIG crystal dissolved into CuO compound liquid phase and then Y element which is considered no solubility in solid CuO compound moved to the grain during cooling. The abnormal grain growth up to 150${\mu}{\textrm}{m}$ at CuO 8.6mole% was shown due to shape accomdation reaction and local liquid distribution. The apparent density of YIG shows minimum at CuO 8.6 mole% due to abnormal grain growth and the saturation magnetization decrease dramatically at 32.5mole% due to orthoferrite formation.

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축계 진동 저감을 위한 수직형 안내 베어링의 최적 설계 (An Optimal Design of a Vertical Guide Bearing for Vibration Reduction)

  • 하현천;박철현;김형자
    • 동력기계공학회지
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    • 제5권3호
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    • pp.64-72
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    • 2001
  • This paper describes an optimal design technology in a segment type vertical guide bearing for vertical rotating machinery. Segment type vertical guide bearings have widely used for vertical rotating machinery, however bearing problems, such as excessive vibration and temperature rise, frequently take place in the actual machine. Such excessive vibration magnitude and/or abnormal bearing metal temperature rise result in serious damage and economic losses. Thus the segment type vertical guide bearing should be designed to get optimal characteristics in order to maintain stable operation without bearing failure due to abnormal vibration and/or abnormal bearing metal temperature. The preload ratio is the most important parameter in designing the segment type vertical guide bearing. Because adjustment of the bearing preload by changing the bearing clearance could easily control both the bearing stiffness and the cooling effect. In the paper, the influence of the preload effects on the bearing metal temperature and the bearing stiffness has been investigated both theoretically and experimentally in order to find out an optimum preload ratio. Results show that the segment type vertical guide bearing has an optimum preload ratio at which the bearing stiffness reaches a masimum value while the bearing metal temperature is minimized.

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태풍에 의해 발생하는 한국근해 해황이상변동 (Abnormal Oceanic Conditions Caused by Typhoons Around the Korean Peninsula)

  • 서영상;구지영;황재동;이나경;김복기;장이현;강용균;이동인
    • 한국수산과학회지
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    • 제36권4호
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    • pp.417-429
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    • 2003
  • Abnormal oceanic conditions associated with the passage of typhoons are examined using hydrographic and satellite data 1990-2002. During the passage period of typhoons in the Korean waters, an abrupt decrease of sea surface temperature (SST) in range of 5 to $8^{\circ}C$ was observed. The areas of SST decrease were an order of 100-200 km, and the low SST lasted about 15-25 days after passage of typhoon. After passage of typhoon, the water temperatures in the surface mixed layer of 30 m show negative anomalies for quite a long period. In addition, stratification parameters were substantially decreased and chlorophyll a density was rapidly increased.