• Fisheries and Aquatic Sciences
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• 제24권7호
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• pp.243-259
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• 2021

The spatial and temporal behaviors and fluctuations of the cold water that appeared in the South East Sea and the East Sea coast from 2016 to 2017 were investigated. The water temperature drop was large in the east coast from April to June and the southeast coast from July to September, and the temperature drop period was longer in the southeast coast. The water temperature fluctuated sensitively to the wind direction, and it gradually decreased in the southwest wind but rose as if jumping in the northeast wind. Wind stress and surface water temperature had an inverse correlation, which was larger in Bukhang-Idukseo, and decreased toward the north of Guryongpo. The cold water appeared mainly in Geojedo-Pohang after 1 to 2 days when the southwest wind was strong, but when the wind became weak, it shrank to the Idukseo (Ulgi-Gampo) and extended into the open sea in a tongue shape. Cold water was distributed only in Samcheok-Toseong in mid-May, Idukseo-Guryongpo and Hupo-Jukbyeon-Samcheok from late May to mid-July, and Bukhang-Idukseo in August-September. The intensity of cold water was greatest in mid-August, and the center of cold water descended from the east coast to the southeast coast from spring to summer. The water temperature fluctuation was dominant at the periods of 1 d and 7-21 d. In wavelet spectrum analysis of water temperature and wind, wind speed increase-water temperature decrease showed phase difference of 12 h in 2 d, 18 h in 3 d, 1.5 d in 4-8 d, and 2-3 d in 8-24 d period. The correlation between the two parameters was large in Geojedo and Namhang, Bukhang-Idukseo, Guryongpo-Jukbyeon, and Samcheok-Toseong. Monitoring stations with high correlation in all periods were generally parallel to the monsoon direction.

• Journal of Biosystems Engineering
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• 제36권5호
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• pp.319-325
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• 2011

This study was conducted to figure out the diagnosis basis of cooling performance depending on water amount in the refrigerant of air conditioner, which can be estimated by the temperatures and pressures along the refrigerant circulation line. A car air conditioner of SONATA III (Hyundai motor Co., Korea) was tested at maximum cooling condition at the engine speed of 1500 rpm in the room controlled at 33~$35^{\circ}C$ air temperature and 55~57% relative humidity conditionally. Measured variables were temperature differences between inlet and outlet pipe surfaces of the compressor, condenser, receive drier and evaporator; and high pressure and low pressure in the refrigerant circulation line; and temperature difference between inlet and outlet air of the cooling vent of evaporator. In this study, changes of the water amount in the refrigerant were correlated to the temperatures and pressure changes and also water amount caused poor cooling performance. As water amount increased in the refrigerant in the air conditioner, the performance of the cooling or the heat transfer became worse. Temporal variations of the surface temperature of the evaporator outlet pipe and the low-side pressure showed various patterns that could estimate the water amount. When the water amount caused bad cooling performance, the patterns of the temperature of the evaporator outlet pipe indicated irregular fluctuation greater than $5^{\circ}C$. When the diagnosis system is using just external sensors of the low-side pressure and the temperatures of inlet and outlet air of cooling vent of the evaporator, the precise pattern of bad cooling performance caused by excess water amount in the cooling line was irregular pressure fluctuation, 25 kPa under 120 kPa, and temperature, $12^{\circ}C$ and less.

• 수산해양기술연구
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• 제17권2호
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• pp.105-108
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• 1981

우리나라 남부해안기후의 특성과 수온과의 관계를 알아보기 위하여 해안지방인 부산, 여수, 목포를 준표준 내륙지방으로 광주와 대구, 인근 해양의 가덕도, 소리도, 홍도의 수온을 선정하여 20년 간(1960~1979)의 관측자료로서 기온, 습도, 강수량을 조사 분석한 결과는 다음과 같다. 1) 해안지방(부산, 여수, 목포)은 해양의 영향으로 내륙지방(대구, 광주)보다 기온의 연교차가 적고 기온이 수온보다 높을 때는 내륙지방이 해안지방의 기온보다 높고, 수온이 기온보다 높을 때는 내륙지방이 해안지방보다 낮다. 2) 수온과 기온의 차에 따라서 내륙지방과 해안지방의 기온차가 결정되며(상관계수 0.9이상) 그 양적 예측도 상관관계식을 활용함으로써 가능하다고 생각된다. 3) 해안지방과 내륙지방의 습도의 차이도 기온의 경우와 비슷하게 나타났으나 목포는 지형적인 영향으로 다른 해안지방과 다르게 나타났다. 4) 수온과 기온의 차이에 따라서 해안지방과 내륙지방의 습도의 차이가 결정된다(상관계수 0.9이상, 목포제외), 그러므로 그 양적 해석도 가능하다. 5) 남해안지방의 강수량은 내륙지방과 그 차이가 뚜렷하게 나타나지는 않았다.

• 한국식품과학회지
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• 제28권4호
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• pp.632-637
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• 1996

가정용 냉장고의 냉장실 온도는 통상 $4^{\circ}C$를 적용하고 있으나, 냉장온도를 $2^{\circ}C$로 낮추고, 온도 편차를 줄일 경우 저장효과의 향상 정도를 비교하기 위하여, 각각 다른 조건에 저장한 과일과 어패류의 품질을 비교 측정하고 아울러 냉장온도에서 생육이 가능한 미생물의 생육정도를 비교하였다. 냉장 온도를 $2^{\circ}C$로 낮추고 온도 편차를 ${\pm}0.3^{\circ}C$ 정도로 낮춘 경우 사과의 경도는 저장 14일째까지 크게 변화하지 않았으나, $4^{\circ}C$의 냉장고에서는 7일 이후 경도가 서서히 감소하는 것으로 나타났으며, 도미의 근단백질 분해 정도 또한 $2^{\circ}C$에서는 느리지만, 저장온도가 높거나 온도편차가 심할 경우 근단백질의 분해가 빨리 나타나 도미의 신선도가 빨리 저하됨을 보여 주었다. 굴의 저장 중 미생물수의 변화는 $2^{\circ}C$에서는 저장 9일째까지 균수의 증가를 보이지 않은 반면, 저장온도가 $4^{\circ}C$인 경우 저장 5일 이후 급격한 증가를 보였고, pH 저하 또한 $2^{\circ}C$에서는 비교적 완만하였으나 $4^{\circ}C$에서는 급격히 저하되었다. Listeria monocytogenes는 우유 중에서는 $2^{\circ}C$에서도 성장하였으나, 햄에서는 냉장온도가 $2{\pm}0.3^{\circ}C$인 경우 증식이 억제되어 생존 균수가 감소하였고, $4{\pm}1.2^{\circ}C$인 경우 약간 성장하였고, 온도 편차가 보다 심한 $4{\pm}4^{\circ}C$에서는 성장이 지속되어 생존균수의 증가를 보여 주었다. 따라서 냉장온도를 $2^{\circ}C$로 낮추고 온도의 편차를 줄임으로써 과일이나 어패류의 저장기간을 보다 연장시키고 유해 미생물의 증식이 상당히 억제될 수 있으리라 기대된다.

• 한국토양비료학회지
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• 제22권1호
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• pp.12-17
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• 1989

수도생육(水稻生育)에 영향(影響)이 큰 답수온(畓水溫) 및 지온(地溫)이 지형특성(地形特性)에 따라 어떻게 변화(變化)하는가를 밝히고자 수도재배(水稻栽培) 기간중(期間中) 표고(標高), 경사(傾斜) 및 관개방법(灌漑方法)이 다양(多樣)한 조건(條件)에서 기온(氣溫), 수온(水溫), 지온(地溫) 및 수도생육상황(水稻生育狀況)을 조사(調査)하였다. 1. 표고(標高),가 100 m에서 700 m로 높아짐에 따라 기온(氣溫), 수온(水溫) 및 지온(地溫)은 공(供)히 떨어졌으며 표고(標高) 100 m당(當) 각각(各各) 0.64, 0.84, $0.82^{\circ}C$씩 감소(減少)되는 경향(傾向)이었다. 2. 유수형성기(幼穗形成期)의 최고수온(最高水溫)은 표고(標高)가 높아짐에 따라 서서히 감소(減少)되었으나 최저수온(最低水溫)은 급격(急激)히 낮아져서 표고(標高) 증가(增加)에 따른 수온(水溫) 감소(減少)는 주(主)로 최저수온(最低水溫)에 의해 영향(影響)을 받고 있음을 알 수 있었다. 3. 답수온(沓水溫)은 관개수원(灌漑水源), 관개방법(灌漑方法)에 따가서도 차이(差異)가 있었으며 특(特)히 동일(同一) 필지(筆地) 내(內)에서도 위치(位置)에 따라 수온(水溫)이 평균(平均) $1.6^{\circ}C$, 지온(地溫)이 평균(平均) $2.8^{\circ}C$나 차이(差異)가 있었고 이에따라 수도생육(水稻生育)도 크게 영향(影響)을 받아 간장(桿長)이 유의성(有意性) 있게 감소(減少)되었다. 4. 지하수(地下水) 양수관개답(揚水灌漑畓)은 일반(一般) 관개지역(灌漑地域)보다 관개간격별(灌漑間隔別)로 빙온변화(氷溫變化)가 크게 나타났다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.332-336
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• 2007

Temperature is an essential process variable in nanoimprint lithography(NIL) where the temperature varies between room temperature and above the glass transition temperature. To simulate NIL process, we employ both the Nose-Poincare method for temperature controlled molecular dynamics(MD) and force field for polymer material i.e. polymethyl methacrylate(PMMA), which is most widely selected as NIL resist. Nose-Poincare method, which convinces the conservation of Hamiltonian structure and time-reversal symmetry, overcomes the drawbacks inherent in the conventional methods such as Nose thermostat and Nose-Hoover thermostat. Thus, this method exhibits enhanced numerical stability even when the temperature fluctuation is large. To describe PMMA, we adopt the force field which account for bond stretch, bending, torsion, inversion, partial charge, and van der Waals energy.

• 천문학회지
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• 제39권4호
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• pp.81-87
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• 2006

A relation between temperature and time has been constructed in the self-consistent model(SCM). This relation is used to calculate the a CMBR temperature. This temperature has been found to be 2.9K. The temperature gradient of microwave background radiation(CMBR) is calculated in the Self Consistent Model. Two relations between Hubble parameter and time derivative of the temperature, have been presented in two different cases. In the first case the temperature is treated as a function of time only, while in the other one, it is assumed to be a function in time and solid angle, beside the assumption that the universe expands adiabatically.

• 대한전자공학회논문지
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• 제27권4호
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• pp.563-570
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• 1990

A silicon pressure sensor made of a full bridge of diffused resistors was designed and fabricated using semiconductor integrated circuit process. Thin diaphragms with 30\ulcorner thickness were obtained using anisotropic wet chemical etching technique. Our device showed strong temperature dependence. Compensation networks are used to compensate for the temperature dependence of the pressure sensor. The bridge supply voltage having positive temperature coefficient by compensation networks was utilized against the negative temperature coefficient of bridge output voltage. The sensitivity fluctuation of pressure sensor before temperature compensation was -1700 ppm/\ulcorner, while it reduced to -710ppm\ulcorner with temperature compensation. Our result shows that the we could develop accurate and reliable pressure sensor over a wide temperature range(-20\ulcorner~50\ulcorner).

• 전기학회논문지
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• 제56권11호
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• pp.1992-1994
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• 2007

In this paper we propose a cryogenic sensor system which can measure the temperature at higher resolution at low temperature using temperature-dependent amplified spontaneous emission of erbium-doped fiber pumped by a 1480 nm laser diode. The measurement resolution of the sensor system could be enhanced through the modulation of injection current of the pump laser diode. The measurement resolution considering the fluctuation of the light source in the sensor system was ${\sim}0.4$ K in the room temperature regime and ${\sim}0.07$ K in the liquid nitrogen temperature regime.

• 한국어병학회지
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• 제15권2호
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• pp.65-75
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• 2002

This study was performed to know the effects of stress induced by the daily fluctuation of water temperture from 18$^{\circ}C$ to 25$^{\circ}C$ up and down for 30 days on the defence mechanism of olive flounder. Puralichthys olivaceus. To make clear the temperature stress on the defense mechanism of the tested fish. several factors of immune response such as counting of leucocyte appearance in peripheral blood, phagocytic activity in whole blood cells, nitroblue tetrazolium(NBT) reduction, chemiluminescence(CL) response, and lysozyme activity were investigated at 28 days after giving the change of water temperature. The fish was controlled under the none feeding condition during experimental period. Mortality of the tested fish was rapidly increased up to 22% within the first one week of the experimental period without any additional stress factors. The number of neutrophil of peripheral blood in the tested group was significantly higher than the control group at the 2nd week. but the number of lymphocyte was significantly lower than the control group at the 1st and 3rd day of the experimental period. respectively. In the NBT reduction test, the activity of macrophage in the control group fish was the highest on the 7th day while that in the tested group was on the 3rd day. Also. the phagocytosis of tested group against formalin killed cells was retarded compared with the control. CL response of the tested group was significantly lower from 2nd to 5lh day of the experimental period than the control. 'The lysozyme activity of tested group was remained higher during the experimental period than the control. Even though the tested fish showed different results in some non-specific factors of immune respceses between tested and control group fish, olive flounder seems highly adaptable in repealed water temperature change in condition after one week under the given temperature fluctuation range.