• Asian-Australasian Journal of Animal Sciences
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• 제10권5호
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• pp.478-483
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• 1997

Six adult female Murrah buffaloes of about 12 years were exposed to solar radiation during summer when minimum and maximum ambient temperatures were 27.1 and $44.1^{\circ}C$, respectively. The skin surface temperature at forehead, middle pinna, neck, rump, foreleg, hind legs were recorded using non-contact temperature measuring instrument and respiration rate and rectal temperature were measured throughout the 24 hours starting from 6:30 AM. The diurnal fluctuations and temperature gradients have been reported for buffaloes. During summer when ambient temperature and solar radiation was maximum, adult buffaloes were not able to maintain their thermal balance even after increasing the pulmonary frequency 5 - 6 times. The changes in skin temperature at various sites indicate that the temperature of skin surface not only varies in relation to exposure but also due to water diffusion and evaporation.

• 조명전기설비학회논문지
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• 제29권9호
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• pp.1-9
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• 2015

The aim of this study is to deduce color temperature and illuminance by conducting the preference & affective evaluation consequent on illuminance change of ambient light in case of the lighting method of ambient light mixed with task light in time of reading which is visual work action among the action in learning space. As a result of the prior survey on preferred lighting method in time of the act of reading targeting 20 experts before doing evaluation, the method of lighting mixed with ambient light and task light was found to be the highest. Such a result is analyzed to be attributable to the fact that the less the difference in illuminance of nearby space and work surface because of the mixed method of lighting, the less the glare, which makes a reader feels easy and concentrate on reading. On the basis of descriptive statistics of evaluation results and impact analysis by category, this study recommends the application of combinations of ambient light illuminance ranging from 40lx to 100lx with color temperature of 5500~6000K in case of the method of lighting mixed with general light and task light.

• Steel and Composite Structures
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• 제14권3호
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• pp.205-227
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• 2013

Current design standards do not provide adequate guidelines for the fire design of cold-formed steel compression members subject to flexural-torsional buckling. Eurocode 3 Part 1.2 (2005) recommends the same fire design guidelines for both hot-rolled and cold-formed steel compression members subject to flexural-torsional buckling although considerable behavioural differences exist between cold-formed and hot-rolled steel members. Past research has recommended the use of ambient temperature cold-formed steel design rules for the fire design of cold-formed steel compression members provided appropriately reduced mechanical properties are used at elevated temperatures. To assess the accuracy of flexural-torsional buckling design rules in both ambient temperature cold-formed steel design and fire design standards, an experimental study of slender cold-formed steel compression members was undertaken at both ambient and elevated temperatures. This paper presents the details of this experimental study, its results, and their comparison with the predictions from the current design rules. It was found that the current ambient temperature design rules are conservative while the fire design rules are overly conservative. Suitable recommendations have been made in relation to the currently available design rules for flexural-torsional buckling including methods of improvement. Most importantly, this paper has addressed the lack of experimental results for slender cold-formed steel columns at elevated temperatures.

• 생물환경조절학회지
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• 제15권4호
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• pp.364-368
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• 2006

This experiment was carried out to figure out the $CO_2$ biomass and the growth response of Chinese cabbage and radish grown under the condition of high temperature and high $CO_2$ concentration to provide the information for the coming climatic change. Chinese cabbage and radish were cultivated in spring and autumn seasons under 4 treatments, 'ambient temp.+ambient $CO_2$ conc.', 'ambient temp.+elevated $CO_2$ conc.', 'elevated temp.+ ambient $CO_2$ conc.', and 'elevated temp. +elevated $CO_2$ conc.'. The 'elevated temp,' plot was maintained at 5 higher than 'ambient temp. (outside temperature)'and the 'elevated $CO_2$ cone.' plot was done in 650 ppm $CO_2$. The growth of spring-sown Chinese cabbage was worse than autumn-sown one, and was affected more by high temperature than high $CO_2$. concentration. The $CO_2$ biomass of Chinese cabbage was lower as 25.1-39.1 g/plant in spring-sown one than 54.8-63.4 g/plant of autumn-sown one. Daily $CO_2$2 fixation ability was not significantly different between spring- and autumn-sown Chinese cabbage as 1.9-2.9, 2.7-3.1 kg/10a/day, respectively. The $CO_2$ biomass of radish were 87.4-104.6 /plant in spring-sown one and 51.3$\sim$76.4 g/plant in autumn-sown one. Daily $CO_2$ fixation ability of radish were 6.2-10.1 kg/10a/day in spring-sown one and 4.6-6.9 kg/10a/day in autumn-sown one.

• 동력기계공학회지
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• 제18권6호
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• pp.77-83
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• 2014

As the interest on the air pollution is gradually risen up at home and abroad, their vehicle emission regulations have been reinforcing by steps. PM regulation was also reinforced 4times for the last 13years and has been applied to SI vehicles after EURO 5. Additionally, knowing that small particles of PM can easily penetrate deep into lungs PM number was added on the regulation from EURO5+ and is applied to CI vehicles. Also, PN regulation is going to be applied to SI vehicles. But, because the regulation is appled to only a general test mode of each countries that is performed at $25{\pm}5^{\circ}C$, it is unclear whether the regulation can work on the other ambient temperature conditions or not. In this paper, to know that exhaust emission characteristics at the special conditions CI vehicles(CRDi w, w/o DPF) were tested using 5-cycle mode, NEDC mode at 5-ambient temperatures (35, 25, 0, -7 and -15) and the exhaust emission test results were discussed. The results show that the vehicle with DPF emits much low PM(and PM number) on all of the test mode. However, NOx of the other mode was emitted higher than regulation mode. Also. NOx was sharply increased according to decreasing Ambient Temperature.

• 동력기계공학회지
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• 제19권6호
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• pp.47-53
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• 2015

Korea is the geographic location during the summer, the temperature rising to $35^{\circ}C$ and winter temperature is $-15^{\circ}C$ to reduce the air temperature changes, such as relatively large compared to other countries. This increase or decrease of the harmful exhaust gas discharged from automobile substantially inconvenience a significant impact on the active side of the car engine temperature and exhaust gas reducing device receives a large impact on the atmospheric temperature is regulation to be different. However, domestic vehicle emissions test temperature of $20{\sim}30^{\circ}C$ is it does not reflect this situation the actual test temperature to accurately measure the exhaust gas volume of the vehicle is difficult. In this study, domestic automobile exhaust gas test conditions of a test temperature $20{\sim}30^{\circ}C$ various temperatures, including (35, 25, 0, -7, -15, $-25^{\circ}C$) under the two vehicles (2.0L MPI, 2.4 L GDI) as was discussed with respect to the exhaust gas characteristics of the vehicle according to the ambient temperature gas. As a result, domestic emissions test temperature of $25^{\circ}C$ than average conditions were temperature decreases greenhouse gas emissions and increase overall increased by up to 15 times higher. Air temperature and the engine exhaust gas inconvenience a direct effect on the activation temperature required in the reduction unit is determined to be an increase of emissions and greenhouse gases, and also an increase in the variety of lubricants based lubricating and viscosity reduction, such as the engine oil due to the low temperature of these result It is considered that shows the.

• 센서학회지
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• 제5권2호
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• pp.37-46
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• 1996

본 연구에서는 곡선근사법과 퍼지신경망의 열전도도 추론을 이용해 대기온도의 변화에 관계없이 접촉된 물체의 재질 인식이 가능한 시스템에 대하여 기술하였다. 먼저 인간의 손가락과 유사한 구조의 재질 인식용 능동센서를 제작하였고 이를 이용해 접촉된 물체의 온도응답곡선을 측정하였다. 측정된 온도응답곡선을 곡선근사법에 의해 지수함수로 근사화하므로써 측정중의 잡음을 없앨 수 있었고 물체의 열전도 특성을 근사화된 지수함수의 계수와 지수로 표현할 수 있었다. 또한 퍼지신경망을 이용하므로써 열전도 특성의 복잡한 수학적 해석을 피할 수 있었고 패기온도의 변화에 관계없이 임의의 대기온도하에서 물체의 열전도도 추론이 가능하였으며 추론된 열전도도를 이용해 접촉된 물체의 재질을 식별할 수 있었다.

• 한국광학회지
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• 제21권5호
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• pp.190-194
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• 2010

본 연구에서는 측면연마 된 광섬유 브래그 격자를 측면 연마하고 폴리머 상부층(overlay)를 형성시켜 외부 굴절률과 온도를 동시 측정할 수 있는 광섬유 센서 소자를 제안하였다. 외부굴절률 변화에 민감하지 않는 광섬유 브래그 격자를 이용하여 온도를 측정하고 격자를 측면 연마한 후 폴리머 코팅에 의해 소산장 결합을 유도하여 외부 굴절률 변화를 측정하게 된다. 측면 연마된 광섬유 브래그 격자의 온도 민감도는 0.01 nm/oC로 측정되었고 폴리머 상부층의 온도 민감도는 -0.58 nm/oC로 측정되었고 선형구간 별(1.33-1.39, 1.39-1.42, 1.42-1.44) 굴절률 민감도는 498.8 nm/RIU, 694.9 nm/RIU, 1312 nm/RIU로 측정되었다.

• 플랜트 저널
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• 제10권4호
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• pp.24-28
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• 2014

본 연구에서는 150 MW 화력발전소를 기준하여 발전소 건설지역의 최저 대기온도 $-17.1^{\circ}C$부터 최대 대기온도 $36.7^{\circ}C$까지를 $3^{\circ}C$의 일정한 간격으로 구분하여 복수기 압력이 증기터빈의 배압조건을 만족하는 대기온도별 송풍기 수량을 검토하였다. 공랭식 복수기는 대기온도 및 송풍기 운전수량 변화에 따른 냉각공기 순환량에 영향을 받아 운전조건이 변경이 되므로, 대기온도가 복수기 설계기준온도 이상의 경우에는 공랭식 복수기 송풍기의 운전수량을 최대로 해야 하고, 대기온도가 복수기 설계기준온도 미만의 경우에는 증기터빈 배압 운전조건을 만족하는 범위 내에서 송풍기 운전수량을 변화시켜 공랭식 복수기에 가해지는 공기 순환량을 감소시키는 것이 안정적인 발전소 운영을 하는 것임을 확인하였다.

• 한국결정성장학회지
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• 제33권2호
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• pp.61-70
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• 2023

이 논문에서는 기존의 초전도 현상을 바라보는 물리학자들의 생각의 흐름과 한계들을 살펴보고, 통계 열역학적 액체론의 관점에서 제시한 이론적 배경을 통해 상온 상압 초전도체가 개발될 수 있음을 약술하였다. 이것이 가능 할 방안은, 전자들이 돌아다닐 수 있는 상태수가 현저히 제한되는 1-Dimension에 가까운 전자 상태이어야 한다는 것과 그 상태에 있는 전자들이 액체적 특성이 나타날 수 있을 정도로 전자-전자 상호작용이 빈번한 상태이어야 한다는 것이다. 이러한 실행 예로서 우연한 기회에 실마리를 얻어 수많은 실험으로 구조를 밝혀낸 LK-99(본 연구에서 개발한 상온 상압 초전도체의 이름)의 개발 자료를 보고하며, 이에 세계 최초로 상압에서 임계온도가 97℃를 능가하는 초전도 물질의 특성과 발견에 대한 이론적, 실험적 근거를 요약하였다.