• 방재기술
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• 통권37호
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• pp.32-35
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• 2004

나이트 라이트 촛불의 사용이 최근 수년간 증가되어 왔으며, 현재 많은 가정집에서 유행중이다. 그 인기의 이유 중 하나는, 침실과 거실이 잘 장식되어 나오는 텔레비전 제작 프로그램의 인기 상승을 포함하여 상대적으로 저렴하고 이용이 쉽기 때문이다. 본 연구는 주위 공기가 무풍일 때와 유속이 있을 때의 나이트 라이트 알루미늄 케이스의 온도 상승을 단일 촛불 심지와 이중 심지에 대해 조사한다. 보통 이중 심지의 경우 온도상승이 빨랐으며, 쉽게 200 이상에 도달하였다.

• 한국작물학회지
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• 제24권3호
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• pp.21-25
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• 1979

수도 유묘의 내냉성을 증대시키는 방법으로써 저온경화의 가능성과 한계를 구명하고저 품종통일과 진흥을 공시하여 주야간 $30^{\circ}/20^{\circ}$에서 생장한 제3 엽기묘를 6일간 저온경화를 한후 주야간 $8^{\circ}C$ 항온의 저온에 0, 2, 4, 6, 또는 8일간 처리하고 $30^{\circ}$20^{\circ}C 조건에서 냉해를 발현시키므로써 저온경화를 평가하였다. 저온경화방법은 주야간 $30^{\circ}/20^{\circ}C\;생장묘\rightarrow24^{\circ}14^{\circ}C(3일간)\rightarrow18^{\circ}/12^{\circ}C(3일간)\rightarrow8^{\circ}C$ 냉해유발처리의 순서를 갖는 점진적 경화와 $306{\circ}/20^{\circ}C\;생장묘\rightarrow30^{\circ}/20^{\circ}C$, 단 1일 4시간 $8^{\circ}C(2일간)\rightarrow30^{\circ}/20^{\circ}C$, 단 1일 6시간 $8^{\circ}C(2일간)\rightarrow30^{\circ}/20^{\circ}C$, 단 $8^{\circ}C\; 16시간 1회\rightarrow8^{\circ}C$ 냉해유발처리의 단시간 저온의 반복적 경화 2가지 방법이었으며 그 결과는 다음과 같다. 1. 내냉성이 약한 품종 통일은 $8^{\circ}C$ 저온을 4일간 처리하면 경화를 하지 않은 유묘는 묘생존율이 25%에 지나지 않았으나 점전적 경화률은 묘생존율이 59%, 반족적 단시간 경화묘는 묘생존율이 89% 정도로써 저온경화의 효과가 뚜렷하였으나 $8^{\circ}C$ 저온이 6일간 이상이 되면 경화묘들도 묘생존율이 모두 20%이하로 떨어졌다. 2. 내냉성이 강한 품종 진흥은 비경화묘도 $8^{\circ}C$ 저온처리 8일간에서도 묘생존율은 90%이상이어서 묘생존율면에서는 저온경화 효과를 분화시키지 못하였다. 3. $8^{\circ}C$ 저온처리 및 냉해발현후 엽신의 변색고사현상은 품종 통일과 진흥 모두 비경화묘보다는 점진적 경화묘, 그보다는 반복적 단시간 경화묘가 뚜렷하게 정상엽면적비율이 높고 저온경화의 효과가 뚜렷하였다.

• 전기학회논문지
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• 제64권8호
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• pp.1154-1160
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• 2015

This paper describes the thermal characteristics of underground power cable system terminations according to the change of ambient temperature as well as operating temperature. Recently, the failure has been gradually increasing in outdoor termination during winter season because the power demand was increased by electricity heating system. The power demand and outdoor temperature is difference between day time and night time. The temperature difference has an influence on conductor extension and shrinkage due to conductor force as well as thermal mechanical characteristics. These phenomena have daily repeated during heating and cooling period of conductors. In these cases, the insulation of outdoor terminations might be degraded by the reduced interface pressure surrounding stress relief cone. Therefore, in this paper, the thermal characteristics are variously analysed by simulation considering power demand and ambient temperature condition during winter season at epoxy type termination as well as slip-on type termination

• Journal of Korean Neurosurgical Society
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• 제65권1호
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• pp.151-160
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• 2022

Continuous monitoring of intracranial pressure is a well established medical procedure. Still, little is known about long-term behavior of intracranial pressure in normal pressure hydrocephalus. The present study is designed to evaluate periodicity of intracranial pressure over long-time scales using intraventricular pressure monitoring in patients with normal pressure hydrocephalus. In addition, the circadian and diurnal patterns of blood pressure and body temperature in those patients are studied. Four patients, selected with "probable" normal pressure hydrocephalus, were monitored for several dozen hours. Intracranial pressure, blood pressure, and body temperature were recorded hourly. Autocorrelation functions were calculated and cross-correlation analysis were carried out to study all the time-series data. Autocorrelation results show that intracranial pressure, blood pressure, and body temperature values follow bimodal (positive and negative) curves over a day. The cross-correlation functions demonstrate causal relationships between intracranial pressure, blood pressure, and body temperature. The results show that long-term fluctuations in intracranial pressure exhibit cyclical patterns with periods of about 24 hours. Continuous intracranial pressure recording in "probable" normal pressure hydrocephalus patients reveals circadian fluctuations not related to the day and night cycle. These fluctuations are causally related to changes in blood pressure and body temperature. The present study reveals the complete loss of the diurnal blood pressure and body temperature rhythmicities in patients with "probable" normal pressure hydrocephalus.

• 한국지리정보학회지
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• 제17권3호
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• pp.132-146
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• 2014

본 연구에서는 부산(Busan)에 설치된 자동기상관측망(AWS)과 국립수산과학원에서 관측하는 부산(Busan)과 기장(Gijang)지점의 해수면온도(SST)자료를 활용하여 부산(Busan)지역의 연안에서 발생하는 대규모 냉수대에 의해 형성된 차가워진 냉기가 도시기온에 미치는 영향을 살펴보았다. 첫째, 냉수대가 발생한 날(cold water)은 연안지역과 도심지역의 기온차가 약 $1^{\circ}C$이상 나타났으며, 냉수대가 발생하지 않은 날(non cold water)은 연안지역과 도심지역의 기온차가 약 $0.5^{\circ}C$로 냉수대가 발생한 날(cold water)보다 낮은 기온차를 보였다. 둘째, 주간의 경우 냉수대가 발생한 날(cold water)은 연안지역이 도심에 비해 약 $1^{\circ}C$ 정도 낮았다. 반면 냉수대가 발생하지 않은 날(non cold water)은 연안지역과 도심의 기온차가 약 $0.4^{\circ}C$로 냉수대가 발생한 날(cold water)에 비해 낮은 분포 차를 보였다. 반면 야간의 경우는 냉수대가 발생한 날(cold water)의 연안지역이 도심에 비해 약 $1.2^{\circ}C$, 냉수대가 발생하지 않은 날(non cold water)은 연안지역이 도심에 비해 약 $0.9^{\circ}C$ 낮았다. 야간의 기온은 주간의 기온에 비해 냉수대 발생 유 무에 상관없이 높은 기온차를 보였다.

• 한국수산과학회지
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• 제25권2호
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• pp.103-114
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• 1992

1989년 가을에서 1990년 여름 사이 아산만에서 otter trawl로 저어류 자료를 수집하여 아산만 저어류의 주야 및 계절 변동을 분석하였다. 주야 자료는 각 조사시기마다 주야 각각 3-5회씩 수집하였다. 동정된 32종의 저어류 중, Chaturichthys stigmatias, Cynoglossus joyneri, Thrissa koreana, Repomucenus lunatus와 Hexagrammos otakii가 총개체수의 $79.5\%$를 차지하였고, 생체량에서는 C. jeyneri, T. koreana, H. otakii, Raja kenoiei와 Kareius bicoloratus가 $67.1\%$%를 차지하여 우점하였다. 밤에 채집된 개체수와 생체량이 낮보다 많았으나, 그 차이는 통계적으로 유의하지 않았다. 또한 각 계절별 어류 군집구조 및 주요 저어류의 평균체장도 밤낮에 유의한 차이가 없었다. 개체수와 생체량은 여름에 높았고 겨울에 낮아 조사 해역 저어류의 양적 변동은 수온, 혹은 수온과 같은 변화를 보이는 요인에 의하여 결정되는 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.280-287
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• 2001

These studies aimed to determine how lighting might be used to improve feed intake and reduce aggressive behavior in newly weaned pigs. To examine whether this objective could be achieved an experiment was conducted to compare performance, behavior and body condition of weaners over 17-45 days, provided similar lighting quality (i.e. color temperature, color rendering index and lighting distribution) after weaning that piglets experienced prior to weaning. Triphosphor (TP) lighting to simulate daylight was provided during the day while at night, Pascal red (PR) lighting was provided to simulate the night-light piglets previously had received from infrared heating lamps. This treatment was compared to weaners provided conventional cool-white fluorescent light during the day only. Weaners on treatment lighting from 17-45 days of age showed no improvement in body weight or feed conversion at 24, 31, 38 and 45 days compared to the controls. There was, however, a significant improvement (p<0.05) in feed intake in the first week of weaning for weaners provided TP/PR lighting. Over the first 3 days of weaning, pigs on TP/PR lighting showed an increase (p<0.05) in the incidence of ear chewing but reduced (p<0.05) levels of nosing the abdomen of other pigs and reduced (p<0.05) occurrences of being stood on by other pigs. Females exhibited more (p<0.05) mounting and nosing behaviors and rubbing the heads of other pigs than males. On the other hand, males engaged in more (p<0.05) fighting, nipping, ear chewing and standing on other pigs compared to females. Pigs provided PR lighting on the first night of weaning engaged in higher (p<0.05) incidences of nosing and tail sucking behaviors, more (p<0.05) head thrusting, fighting and ear chewing compared to control pigs. The body condition of weaners provided the TP/PR lighting treatment was significantly poorer (p<0.05) compared to weaners on control lighting. In conclusion there was no improvement in production performance of weaners provided new technology lighting apart from the improvement in feed intake in the first week weaners were exposed to the TP/PR lighting.

• Fisheries and Aquatic Sciences
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• 제10권2호
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• pp.74-85
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• 2007

Pacific anchovy (Engraulis japonicus) eggs were collected during the spawning season (2000-2003) using a revised ring net in the coastal waters adjacent to the Geum River Estuary in the West Sea of Korea (Yellow Sea). Anchovy eggs were present from May to September, showing a peak in spawning from June to July when the water temperature and salinity were $17-27^{\circ}C$ and above 30.00 psu, respectively. During the main spawning season, no clear diel cycle (regarding the 24-h sampling period of dusk, night, dawn, and daytime) was detected in the vertical distribution of anchovy eggs near Eocheong Island (50-60m depth). Judging from the developmental stages of the collected eggs, it appeared that anchovies spawned mostly at night and that the eggs hatched at dusk and during the night. The density of anchovy eggs was high in the southwest-northeast direction in June, and spawners appeared to move offshore in July. Mean egg density was higher in June 2002 than in June 2003 when water temperatures and salinities were lower. This study on the spatiotemporal distribution of eggs will contribute to developing management plans for the Pacific anchovy in Korea.

• Asian Journal of Atmospheric Environment
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• 제5권1호
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• pp.29-40
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• 2011

In this study, the effects of an urban thermal environment on air quality were investigated using hourly surface weather observation data and air quality data over six summers from 2000 to 2005 in two cities on the Korean Peninsula. One, the city of Daegu, is representative of basin topography and the other, the city of Busan, represents a coastal area. It is known that the characteristics of an urban thermal environment are represented as an "urban heat island". Here, we focus on the nighttime urban thermal environment, which is called a "tropical night", during the summer. On tropical nights in Busan, the temperature and cloud cover levels were higher than on non-tropical nights. Wind speed did not appear to make a difference even on a tropical night. However, the frequency of southwestern winds from the sea was higher during tropical nights. The prevailing southwest winds in all areas meant an inflow of air from the sea. So at most of the air quality stations, the ozone concentration during tropical nights was lower than during non-tropical nights. In Daegu, the tropical nights had higher temperatures and cloud covers. Despite these higher temperatures, the ozone concentration during the tropical nights was lower than that on non-tropical nights at most of the air quality stations. This feature was caused by low irradiance, which in turn caused an increased cloud cover. Wind speed was stronger during the tropical nights and dispersed the air pollutants. These meteorological characteristics of the tropical nights reduced ozone concentrations in the Daegu Basin.

• 한국태양에너지학회 논문집
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• 제40권1호
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• pp.25-33
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• 2020

It has been reported about the energy saving performance of UFAD(under floor air distribution) system and NPC(night purge cooling) system respectively which are applied for commercial buildings. However, when two systems are used at the same time, the effect of heat transfer from floor plenum to slab may vary depending on the operating conditions of NPC. In this study, cooling energy demands were analyzed for building models with UFAD and NPC by using TRNSYS 17 program. UFAD was applied as a cooling system of the base building model, and the cooling energy demands were compared for 64 cases in which the operating time, supply airflow rate, and outdoor air temperature(T_o) of NPC. As a result, it was confirmed that the cooling energy demands were reduced to 30 ~ 80% level compared to UFAD alone, and in particular, the energy demand was reduced in proportion to the supply airflow rate or the operating time while T_o was 16 ~ 20℃. However, when T_o was 22℃, the increase in the supply airflow rate or the operating time results in a disadvantage in terms of cooling energy demands. In addition, the cooling energy demands for UFAD+NPC model were analyzed by applying weather data from three regions with different average outdoor air temperatures. As a result, the cooling energy demand of operating NPC only when T_o was below 20℃ was reduced by 27% compared to that of operating NPC continuously for 8 hours.