• Journal of Ecology and Environment
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• v.30 no.2
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• pp.143-149
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• 2007

To certify predictability for the times of phenological stages from cumulative air temperature in springtime, the first times of budding, leafing, flower budding, flowering and deflowering for 14 woody plants were monitored and air temperature was measured from 2005 to 2006 at Namsan. Year day index (YDI) and Nuttonson's Index (Tn) were calculated from daily mean air temperature. Of the 14 woody species, mean coefficient of variation was 0.04 in Robinia pseudo-acacia and 0.09 in Alnus hirsuta. However, mean coefficient of variation was 0.30 in Forsythia koreana and Stephanandra incisa and 0.32 in Zanthoxylum schinifolium. Therefore, the times of each phenological stage could be predicted in the former two species but not in latter three species by two indices. Of the five phenological stages, mean coefficient of variation was the smallest at deflowering time and the largest at budding time. In five phenological stages, mean coefficient of variation of YDI was in the range of $0.11{\sim}0.21$ but that of Tn was in the range of $0.15{\sim}0.26$. Therefore, the former was a better index than the latter. Of the species-phenological stage pair, coefficient of variation of YDI was 0.01 in Acer pseudo-sieboldianum - flower budding and below 0.05 in 11 pairs, whereas the YDIs over 0.40 were 4 pairs comprising of Prunus leveilleana - budding (0.51). Coefficient of variation of Tn was 0.01 in A. hirsuta - budding and below 0.05 in 8 pairs. The Tns over 0.40 were 5 pairs comprising of F. koreana - flower budding (0.66).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.3
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• pp.209-217
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• 1997

The objective of this paper is to improve a discomfort caused by the unequal airflow and vertical temperature difference by buoyancy of the supplied hot air in the conventional hot air heating system. In order to the model experiment we manufactured the hot air heater with two air outlet and a model room. We observed the temperature, velocity and airflow distribution and calculated values of PMV and PPD using mean value of central verticality section's air temperature and velocity. We could improve distribution of vertical temperature and velocity at the central section of the model room owing to correlation of hot air of two air outlet.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1274-1279
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• 2004

We performed the numerical study on the comparison of thermal comport performance indices for cooling loads in the classroom when the 4-way cassette air-conditioner is mounted on the ceiling. We investigated the velocity and the temperature distribution of the classroom as with respect to the variation of the air diffusion angle of the air-conditioner. Air diffusion performance index and Predicted mean vote were used for analyzing the characteristics of the thermal comport in the classroom and comparing their values each other. From the numerical results, we knew that the thermal comport is largely affected by the air diffusion angle and velocity of the air-conditioner. And we also found out that the qualitative tendency of the distribution between Air diffusion performance index and Predicted mean vote is very similar in all occupied zone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.55-59
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• 1968

The relation of air temperature between early summer and early autumn from 1916 to 1966 was investigated. The data are brought by the statistical analysis for the purpose of the long range weather forecast. he results are summarized as follows : 1. The air temperature in early autumn at Mokpo is largely influenced by that of early summer. That is, when the air temperature in early summer is higher than the average, the temperature in early autumn has the possibility of being higher temperature in early autumn than average, the possibility being as much as $60\%$. On the contrary, when the former is lower, the latter has a possibility of becoming $74\%$ below the normal year. 2. The monthly ranges of forcastable mean air temperature in early autumn will be computed by the types of total variation in early summer and the standard deviation in early autumn.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.413-422
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• 2000

Samples of banana were dried in a two-stage heat pump dryer capable of producing stepwise control of the inlet drying air temperature while keeping absolute humidity constant. Two stepwise air temperature profiles were tested. The incremental temperature step change in temperature of the drying air about the mean air temperature of 30 $^{\circ}C$ was 5 $^{\circ}C$. The total drying time for each temperature-time profile was about 300 minutes. The drying kinetics and color change of the products dried under these stepwise variation of the inlet air temperature were measured and compared with constant air temperature drying. The stepwise air temperature variation was found to yield better quality product in terms of color of the dried product. Further, it was found that by employing a step-down temperature profile, it was possible to reduce the drying time to reach the desired moisture content.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.4
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• pp.11-16
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• 2015

Spatial and temporal information on near-surface air temperature is important for understanding global warming and climate change. In this study, the estimation algorithm of near-surface air temperature in Korea was developed by using spatial homogeneous surface information obtained from satellite remote sensing observations. Based on LST(Land Surface Temperature), NDWI(Normalized Difference Water Index) and NDVI(Normalized Difference Vegetation Index) as independent variables, the multiple regression model was proposed for the estimation of near-surface air temperature. The different regression constants and coefficients for warm and cold seasons were calculated for considering regional climate change in Korea. The near-surface air temperature values estimated from the multiple regression algorithm showed reasonable performance for both warm and cold seasons with respect to observed values (approximately $3^{\circ}C$ root mean-square error and nearly zero mean bias). Thus;the proposed algorithm using remotely sensed surface observations and the approach based on the classified warm and cold seasons may be useful for assessment of regional climate temperature in Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.3
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• pp.164-169
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• 2004

A spatial interpolation scheme incorporating local geographic potential for cold air accumulation (TOPSIM) was used to test the feasibility of operational frost warning in Chatancheon basin in Yeoncheon County, where the introduction of new crops including temperate zone fruits is planned. Air temperature from April to June 2003 was measured at one-minute intervals at four locations within the basin. Cold-air accumulation potentials (CAP) at 4 sites were calculated for 3 different catchment scales: a rectangular area of 65 x 55 km which covers the whole county, the KOWACO (Korea Water Corporation) hydrologic unit which includes all 4 sites, and the sub-basins delineated by a stream network analysis of the digital elevation model. Daily minimum temperatures at 4 sites were calculated by interpolating the perfect prognosis (i.e., synoptic observations at KMA Dongducheon station) based on TOPSIM with 3 different CAPs. Mean error, mean absolute error, and root mean square error were calculated for 45 days with no precipitation to test the model performance. For the 3 flat locations, little difference was detected in model performance among 3 catchment areas, but the best performance was found with the CAPs calculated for sub-basins at one site (Oksan) on complex terrain. When TOPSIM loaded with sub-basin CAPs was applied to Oksan to predict frost events during the fruit flowering period in 2004, the goodness of fit was sufficient for making an operational frost warning system for mountainous areas.

• Atmosphere
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• v.15 no.3
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• pp.179-186
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• 2005

Due to several difficulties, a number of Automatic Weather Systems (AWS) operated by Korea Meteorological Administration (KMA) are located on the rooftop so that the forming of standard observation environment to obtain the accuracy is needed. Therefore, the air temperature of AWSs on the synthetic lawn and the concrete of the rooftop is compared with the standard observation temperature. The hourly mean temperature is obtained by monthly and hourly mean value and the difference of temperature is calculated according to the location, the weather phenomenon, and cloud amount. The maximum and the minimum temperatures are compared by the conditions, such as cloud amount, the existence of precipitation or not. Consequently, the temperature on the synthetic lawn is higher than it on the concrete so that it is difficult to obtain same effect from ASOS, on the contrary the installation of AWS on the synthetic lawn seem to be inadequate due to heat or cold source of the building.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.1
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• pp.101-110
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• 2022

For this purpose, the authors proposed and proved usefulness of the modified mean skin temperature which is integrated mean radiation temperature and the effect of floor contacted heat conduction. The mean radiation temperature is applied form factor between half cross-legged human body and surrounding wall of indoor. In addition the floor contacted heat conduction is applied heat transfer coefficient of half cross-legged human body. Eight Korean young men were targeted for the experiment. From the experiment the authors excerpted physiological reaction and psychological reaction in Ondol environment which is combined physiccal environmental factor of artificial climate chamber, air and floor temperature. As a result of the experiment it is confirmed that heat conduction has more impact than heat exchange from existing research for the heat exchange between half cross-legged human body and surrounding wall in Ondol thermal environment. Thereby, it is proved the effectiveness of the modified mean skin temperature which is added floor contacted temperature to the Ondol thermal environmental evaluation index.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.610-615
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• 2003

Electric rolling stock is one of major public transportation because of an increase in population and heavy traffic problems. The passengers under the influenced of indoor air quality such as air temperature, relative humidity and air velocity. Ventilation system on passenger cars should be designed for the health and comfort of the passengers. One of the main aim is to create an acceptable thermal environment without draught problems. The draught sensation increases when the air temperature decreases and the air velocity increases. Airflow in passenger cars is turbulent. Lateral temperature and humidity gradients in the electric rolling stock have been studied. And, the difference in the mean temperature and relative humidity measured at 0.7, 0.9, 1.2, 1.7 m above from the floor.