• Journal of Sensor Science and Technology
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• v.6 no.2
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• pp.81-86
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• 1997

Platinum thin films were deposited on $SiO_{2}/Si$ and $Al_{2}O_{3}$ substrates by DC magnetron sputtering for RTD (resistance thermometer devices) temperature sensors. The resistivity and sheet resistivity of these films were decreased with increasing the annealing temperature and time. We made Pt resistance pattern on $Al_{2}O_{3}$ substrate by lift-off method and fabricated Pt-RTD temperature sensors by using W-wire, silver epoxy and SOG(spin-on-glass). In the temperature range of $25{\sim}400^{\circ}C$, we investigated TCR(temperature coefficient of resistance) and resistance ratio of Pt-RTD temperature sensors. TCR values were increased with increasing the annealing temperature, time and the thickness of Pt thin films. Resistance values were varied linearly within the range of measurement temperature. At annealing temperature of $1000^{\circ}C$, time of 240min and thin film thickness of $1{\mu}m$, we obtained TCR value of $3825ppm/^{\circ}C$ close to the Pt bulk value.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.265-273
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• 2011

Hyporheic zone, where groundwater-stream water mixing occurs, sensitively responds to heat of groundwater and stream water temperature. Variation of stream water temperature has short time period and time dependent, because stream water temperature is influenced by daily fluctuation and seasonal air temperature. On the other hand, groundwater temperature is insignificant. In this study, we conducted 1-dimensional heat transfer analysis. The results show that there are differences of temperature distribution between gaining stream and losing stream with flux in hyporheic zone. Especially, variations of hyporheic water temperature show a significant difference in adjacent streambed, Also, the results shows that distribution of temperature was more affected by groundwater direction than intensity of flux.

• Journal of the Korean Arthroscopy Society
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• v.6 no.1
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• pp.49-53
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• 2002

Purpose : To document the change in the temperature of the knee joint at the initiation and conclusion of an arthroscopic procedure and correlate this temperature change with other intra-operative variables. Material and Methods : Temperature measurements were performed in 40 consecutive patients(42 cases) that underwent arthroscopic surgery. Temperature measurements were taken at the initiation of the procedure, before and after inflation of the tourniquet. The last measurement was recorded at the end of the surgical procedure. Results : The mean knee joint temperature evaluated before inflation of the torniquet was $35.1{\pm}1.0$, at the end of surgery, $24.6{\pm}1.5^{\circ}C$. The mean temperature change observed from the beginning to the end of the procedure was $10.5^{\circ}C$. The student t test showed a statistically significant difference of the initial joint temperature(p<0.01) between the patient with no and+1 effusion / between the patient with no and +2 effusion. The temperature at the end of the procedure was found to be statistically low correlated (p<0.01) with the lower temperature of the irrigant and the lengthening of the arthroscopic procedure. Conclusion : Consideration should be given to maintaining the saline irrigant to more physiologic temperature to protect the articular cartilage from any possible temperature induced damages.

• Korean Journal of Heritage: History & Science
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• v.53 no.1
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• pp.52-63
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• 2020

This study was conducted in order to evaluate the characteristics of air temperature fluctuation inside the Daegeumgul, Ondaldonggul, and Seongnyugul Caves, which are the most representative limestone caves in Korea, and also to assess the effects of air temperature on cave temperature. Temperature was measured hourly at three sites in Daegeumgul, Ondaldonggul, and Seongnyugul Caves from April 13 to June 25, 2019. Additionally, air temperature data for the areas around the caves was provided by the Meteorological Administration. Using this collected data, the basic statistical measure of fluctuation characteristics over time was ascertained, and time series analyses were performed. Wide variation of temperature was exhibited in the order of the cave entrance, the cave water inflow point, and the midpoint. Cave temperature was observed to increase gradually during the study period. There was a vast range in temperature at the Daegeumgul station located approximately 150 m outside the cave, but it remained nearly constant beyond the midpoint. Although the effect of air temperature was not significant due to the influence of visitors, the effect of air temperature on cave temperature gradually decreased from the entrance to the interior. At Ondaldonggul, there was a wide range in temperature recorded at the entrance due to the influence of air temperature, but it stayed almost constant in the interior. However, at the site where cave water flows into the cave, temperature was influenced by the cave water temperature. At Seongnyugul, there was a distinct fluctuation in temperature recorded at the cave entrance, while the middle of the cave remained nearly constant. Temperature fluctuated due to the air temperature at the entrance, while at the middle of the cave, measurements were expected to be affected to a greater extent by the lake water temperature than by the air temperature. However, this pattern was not observed. According to the time series analysis results, in all caves, fluctuations of air temperature affected cave temperature after approximately one hour. Cave size and structure, water presence, the entrance's size and shape, air flow, and visitor patterns can all influence cave temperature. Therefore, consideration of these factors is very important in the pursuit to clearly understand cave temperature characteristics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.345-350
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• 2017

Downsizing is widely applied to diesel engines in order to improve fuel efficiency and reduce exhaust emissions. Engine sizes are becoming smaller but pressure and temperature inside combustion chambers are increasing. Therefore, research for fuel spray under high pressure and temperature conditions is important. A constant volume chamber which simulates high temperature and pressure likely to be found in diesel engines was developed in this study. Pressure and temperature were increased abruptly because of ignition of the pre-mixture in the constant volume chamber. Then pressure and temperature were gradually decreased due to the heat loss through the chamber wall. Fuel spray occurred when temperature and pressure were reached at the target condition. In this experiment, the temperature condition should be exactly defined to understand the relation between fuel evaporation and ambient temperature. A fast response thermocouple was developed and used to measure the temporal and spatial temperature distribution during the combustion process inside the combustion chamber. In the results, the core temperature was slightly higher than the bulk temperature calculated by the gas equation. Ed-note: do you want to say 'ideal gas equation'? This was attributed to the heat transfer loss through the chamber wall. The vertical temperature deviation was higher than the horizontal temperature deviation by 5% which resulted from the buoyancy effect.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.468-475
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• 2005

To understand spatiotemporal changes of temperature and humidity in Lentimula edodes cultivation sheds, temperature, relative humidity were measured with HOBO H8 series sensors in log cultivation sheds and sawdust cultivation sheds. The results obtained from October in 2003 to October in 2004 were as follows; 1. Horizontal temperature changes were smaller at center of cultivation shed inside than comer of cultivation shed inside, while relative humidity changes were greater about 3% at center of cultivation shed inside than corner of cultivation shed inside. 2. Vertical temperature changes showed that the temperature was higher at above than at below when the temperature rises, while the temperature was lower at above than at below when the temperature falls. Thus close to soil surface temperature showed a little fluctuation. Vertical relative humidity changes showed that the relative humidity was lower at above than at below when the temperature rises, while the relative humidity was higher at above than at below when the temperature falls. After all temperature and relative humidity was the opposite in cultivation shed. 3. It's showed in log cultivation shed that the minimum temperature was a subzero temperature until the end of April, while the minimum temperature did above zero after the beginning of the May. Besides a winter was the greatest at daily temperature range during the four season, about $30^{\circ}C$. On the other hand the minimum relative humidity was less than 20% at April, May and June but more than 40% after May.

• Journal of Sensor Science and Technology
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• v.12 no.5
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• pp.225-230
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• 2003

Nowadays, laserthermia is widely used to treat malignant tumors with generating heat as the one of minimal invasive surgeries. Generally, the laserthermia probe system consists of the fiber-optic laser and light guides, image guide and temperature sensor. It is very important to measure the temperature of treating tumor and make a stable temperature ($42{\sim}43^{\circ}C$) during the treating time. Therefore, laserthermia probe needs temperature sensor which can measure it exactly and fast. In this study, to develop a new type of temperature sensor with LC(liquid crystal) and optical fiber, the reflectivity of LC according to the temperature changes are measured. Also, the relationships are derived from the results.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.12
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• pp.2407-2414
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• 1992

Constant temperature hot wire air flow meter for automobiles requires temperature compensation system because hot wire output signal is sensitive to ambient temperature variations as well as fluid velocity. The objectives of the present study are to design an air flow meter circuit which is capable of compensating the hot wire output signal for ambient temperature variations and to investigate the mechanism of such temperature compensation. This circuit is composed of platinum hot wire, platinum resistor, two variable resistors, a constant resistor and a DC-amplifier. In particular, by simply replacing a constant resistor in one of the bridge arms of the conventional circuit with platinum resistor and a variable resistor for the purpose of temperature compensation, the deviation of output signal with respect to ambient temperature variations between 27deg. C 70deg. C could be reduced to less than 2.5% for mass flow rate and to less than 5% for velocity respectively. The mechanism of temperature compensation against ambient temperature variations was explained by means of measuring the heat transfer coefficient with hot wire temperature variations and analyzing and analyzing conventional empirical equations qualitatively.

• Fire Science and Engineering
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• v.28 no.4
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• pp.8-13
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• 2014

In order to improve safety for hydrogen network infrastructure, the ignition temperature by hot wire was investigated for different hydrogen compositions in pipelines. The result shows that minimum temperature for ignition decreased with decreasing hydrogen composition. The minimum temperature was confirmed at a hydrogen composition of approximately 10 vol.%. The one of the reasons is supposed that buoyancy force should generate the convection of gas mixture. It was also found that humidity had a little effect on ignition temperature, flame temperature.

• Journal of Digital Convergence
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• v.11 no.10
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• pp.711-718
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• 2013

This study examined the effect of 3 evaluation factors(extraction temperature, extraction time and drinking temperature) on the 5 tastes (sour, sweet, malty, salty and bitter) of coffee. the aim of this experiment were threefold: i) to investigate the change of the 5 tastes depending on the each 3 evaluation factor ii) to examine the change of the 5 tastes depending on the extraction time, drinking temperature under fixing the group of extraction temperature iii) to research the preference for the taste of coffee depending on 3 evaluation factors. As a result, in relation to the evaluation factors, significance difference was made at the sour taste. And when extraction temperature was higher and extraction time was longer, the sour taste was felt stronger. To the contrary, when drinking temperature was lower, sour was stronger. When the extraction Temperature group was controlled, the sour and malty taste were stronger. The sour taste was stronger when drinking temperature was lower and delicate flavor was stronger when drinking temperature was higher. High preference was demonstrated at extraction temperature($98^{\circ}C$), extraction time(0 minute), drinking temperature($60^{\circ}C$) and higher malty taste.