• Ocean and Polar Research
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• v.29 no.1
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• pp.1-8
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• 2007

A series of long chain unsaturated ketone (alkenone) was identified in the particulate organic matter sampled from surface water of the eastern South Sea, Korea. The seawater temperature based on the $C_{37}$ alkenone was calculated by using several different equations of unsaturation index(${U^{K'}}_{37}$), compared with in situ CTD temperature. Among the previously reported equations, the equation(0.044T-0.204) which was proposed by Sawada et al.(1996) seems to be the most useful for the calculation of $C_{37}$ alkenone temperature, showing average $0.51^{\circ}C$ difference between ${U^{K'}}_{37}$ temperature and in situ CTD temperature. This result suggest that alkenone should be a useful molecular biomarker for reconstructing paleo-environmental change in the South and East Sea, Korea. However, it is required to establish more reliable equation for the calculation of $C_{37}$ alkenone temperature.

• Advances in environmental research
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• v.1 no.1
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• pp.69-82
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• 2012

Based on the measurement data of the particulate matter with an aerodynamic diameter of less than or equal to a nominal 10 ${\mu}m$ (PM10) by the ${\beta}$-ray absorption method (BAM) equipped with an inlet heater and the gravimetric method (GMM) at two coastal sites in Korea, the optimal inlet heater temperature was estimated. By using a gas/particle equilibrium model, Simulating Composition of Atmospheric Particles at Equilibrium 2 (SCAPE2), water content in aerosols was estimated with varying temperature to find the optimal temperature increase to make the PM10 concentration by BAM comparable to that by GMM. It was estimated that the heated air temperature inside the BAM should be increased up to $35{\sim}45^{\circ}C$ at both sites. At this temperature range, evaporation of volatile aerosol components was minor. Similar ($30{\sim}50^{\circ}C$) temperature range was also obtained from the calculation based on the absolute humidity which changed with ambient absolute humidity and chemical composition of hygroscopic species.

• Solar Energy
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• v.12 no.2
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• pp.1-8
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• 1992

Identifying characteristics of heating and cooling systems requires estimation of thermal load of specific time interval, especially in cases that its system is operated intermittently, by using thermal storage, of in a partial load condition. Estimating the thermal load, however, needs to forecast hourly weather data variation. Hence, this paper attempts to examine characteristics of hourly ourdoor temperature variation as a preliminary research for the mathematical modeling of the hourly weather variation. Speculating characteristics of daily minimum and maximum temperature occurances, hourly outdoor temperature variation, and daily temperature differences in the increasing range ($07h{\sim}15h$) and decreasing range($15h{\sim}07h$), we were able to analyze changing patterns of daily temperature differences in each range in terms of daily solar amount, cloud ratio, and other weather data. Results from the multiple regression analysis enables us to conclude that daily differences in the increasing range are strongly affected last night temperature itself while the other range's differences are influenced by many weather data, which are solar amount, the variation of cloud, and the maximum temperature of the previous day.

• Journal of Korean Society on Water Environment
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• v.27 no.6
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• pp.769-775
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• 2011

An experimental study of biofilm nitritation system for high-strength ammonium wastewater has been carried out to examine the temperature effect on different organic and solid concentration. Operating temperature varied from $35^{\circ}C$ to $15^{\circ}C$. The influent N concentration of identical three reactors was adjusted to about $300mg\;NH_4-N/L$. A control unit fed with a synthetic wastewater, while the others were fed with reject water which is consisted of the supernatant of both digester and thickener. The results indicated that nitrite accumulation was stable in temperature range of $35^{\circ}C$ to $25^{\circ}C$. However, nitritation was significantly reduced at below $20^{\circ}C$. Free ammonia (FA) and free nitrous acid (FNA) were major inhibitors to the nitrite oxidizer for nitrite accumulation in lower temperature. From the estimation of temperature coefficient (${\Theta}$) of biofilm and suspended nitritation system, biofilm nitritation system could absorb the negative temperature effect compared with suspended nitritation system.

• Safety and Health at Work
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• v.13 no.1
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• pp.99-103
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• 2022

Background: Firefighters may experience high environmental temperatures or carry out intensive physical tasks, or both, which leads to increased core body temperature and risk of fatalities. Hence there is a need to remotely and non-invasively monitor core body temperature. Methods: Estimated (heart rate algorithm) and actual core body temperature (ingested telemetric pill) measures were collected simultaneously for comparison during training exercises on 44 firefighter volunteers. Results: Prediction of core body temperature varied, with no specific identifiable pattern between the algorithm values and directly measured body core temperatures. Group agreement of Lin's Concordance of 0.74 (95% Upper 0.75, lower CI 0.73), was deemed poor. Conclusion: From individual agreement data Lin's Concordance was variable (Min 0.11, CI 0.13-0.01; Max 0.83, CI 0.86-0.80), indicating that the heart rate algorithm approach was not suitable for core body temperature monitoring in this population group, especially at the higher more critical core body temperatures seen.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.1
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• pp.25-31
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• 2008

Information on daily maximum air temperature is important in predicting the status of plants and insects, but the uneven and sparse distribution of weather stations prohibits timely access to the data in regions with complex topography. Since cumulative solar irradiance plays a critical role in determining daily maximum temperature on any sloping surfaces, derivation of a quantitative relationship between cumulative solar irradiance and the resultant daily maximum temperature is a prerequisite to development of such estimation models. Air temperatures at 8 sideslope locations with similar elevation and slope angle but aspect, circumventing a cone-shaped, grass-covered parasitic volcano (c.a., 570 m diameter for the bottom circle and 90m bottom-to-top height), were measured from June to December in 2007. Daily maximum temperatures from each location were compared with the average of 8 locations (assumed to be the temperature measured at a "horizontal reference" position). The temperature deviation at all locations increased with the day of year (or sun elevation) from summer solstice to winter solstice. Averaged over the entire period, the south facing location was warmer by $1^{\circ}C$ in daily maximum temperature than "horizontal reference" and the north facing location was cooler by $0.8^{\circ}C$ than the reference, resulting in the year round average south-north temperature difference of $1.8^{\circ}C$. In November, both south and north facing slopes showed the greatest deviation of $+2.0^{\circ}C$ and $-1.3^{\circ}C$, respectively in daily maximum temperature at monthly scale. On a daily scale, the greatest deviation was +3.8 and $2.7^{\circ}C$ at the south and north slope, respectively. The cumulative solar irradiance (on the slope for 4 hours from 11:00 to 15:00 TST) explained >60% of the variance in daily maximum temperature deviations among 8 locations, suggesting a feasibility of developing an estimation model for daily maximum temperature over complex topography at landscape scales.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.85-86
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• 2002

For rheology investigation of lubricating oils, first phase diagrams were made from determined free volume based on density measurements and the temperature-pressure relation was estimated using the expansion coefficient of free volume and the temperature-pressure relation of the viscoelastic transition point. Next, the authors proposed the density-pressure-temperature relation and the viscosity-pressure-temperature relation of the tested oils based on the free volume and the phase diagrams. Moreover, it was shown that the Ehrenfest equation or the gradient of the phase diagram is closely related to the expansion coefficient of free volume.

• Journal of Ocean Engineering and Technology
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• v.23 no.2
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• pp.81-86
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• 2009

Infrared thermography was used to determine the location, size, and depth of defects under the surface of M.C nylon. Defects were created in a specimen by back-drilling circular holes. These defects were located at the maximum temperature difference that occurred. The sizes of the defects could be calculated by means of the full width at half of the maximum temperature difference. The depth of a defect could be calculated by the peak time and the maximum temperature difference. The maximum temperature difference between a defect and normal part was decreased with the depth of the defect. And the peak time also slowly appeared with the depth of the defect.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.351-356
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• 2002

Groundwater recharge rate was estimated by applying the groundwater level fluctuation method utilizing Theis (1937) approach with specific yield estimation technique of Shevenell (1996) and the temperature method using observed data from National Groundwater Observation Stations. Results based on analysis of water level observation data of 10 alluvium wells reveal that the recharge rates for 5 wells of Kum river area range 3.7~25.0% and those for 5 wells of Nakdong river area range 3.6~21.7%. Results obtained from the temperature method based on water temperature data indicated that the upward flow resulted from evapotranspiration is dominant for 4 wells of the Kum river area and 5 wells of the Nakdong river area. The other wells showed the downward flow which is related to groundwater recharge in these areas.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.1
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• pp.54-60
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• 2011

Procedures for estimation of insulation thickness for a horizontal pipe for condensation control or personnel protection has been investigated, parallel to the previous work of a vertical wall case. Parameters include pipe diameter, emissivity, thermal conductivity, and operating temperatures. The results indicated that the surface emissivity plays a very important role in the design of insulation, specially for the case of high temperature application with low Bi. The effect of surface radiation in such case could be up to 65% of the total. Required insulation thickness for the surface temperature control increases as pipe diameter increases and as surface emissivity decreases. Adequate revision of specifications or standards to include newly invented insulation materials with high emissivity has been also suggested.