• The Korean Journal of Community Living Science
• /
• v.17 no.2
• /
• pp.49-60
• /
• 2006

It was measured the energy expenditure in each season, the cold tolerance in winter and the heat tolerance in summer. Farmers' adaptability to the change of environment was compared with those of city-dwellers such as indoor workers and street cleaners to determine the effect of living environment, especially living temperature, on the health of human body. It turned out that farmers had experienced wide range of temperature that was higher in summer and lower in winter than indoor workers. Farmers and street cleaners showed seasonal adaptation in energy expenditure, which was high in winter and low in summer. However, indoor workers did not show seasonal changes. Energy expenditure had an inverse correlation with the temperature in work place where subjects spend the longer time in a day except in female indoor workers in Seoul. And It was proved that farmers and street cleaners had stronger cold tolerance and heat tolerance than indoor workers.

• Korean Journal of Ecology and Environment
• /
• v.35 no.2 s.98
• /
• pp.71-78
• /
• 2002

Seasonal change of total bacterial numbers were estimated in Daechung Reservoir from September, 1998 to August, 1999 and environmental factors which affects total bacterial numbers were estimated. Total bacterial numbers ranged between 1.2 and $19.0{\times}10^6\;cells/ml$ and averaged $6.9{\times}10^6\;cells/ml$. Bacterial numbers changed dynamically with season. The bacterial numbers were highest in July and showed peaks in April and July in sites studied except for the HOE (Hoenam site), In the HOE (Hoenam site), total bacterial numbers increased eve the period of March${\sim}$August. The correlation coefficient between bacterial number and chlorophyll a (<$200\;{\mu}m$) was r = 0.72(p< 0.05) at the MAN (man site). Total bacterial numbers in Daechung Reservoir was diversely changed by the seasonal variation of several environmental quality parameters.

• The Korean Journal of Ecology
• /
• v.18 no.1
• /
• pp.137-146
• /
• 1995

Acer pseudo-sieboldianum, A. ginnala, A. negundo and A. saccharinum were selected as materials for the studies on the seasonal fluctuation of chlorophyll content and photosynthetic rates. In all the four species during the growing season except in October, the principal component that determined the total chlorophyll content was chlorophyll a. Content of chlorophyll b increased with leaf age, but that of chlorophyll a decreased. In contrast to A. saccharinum and A. pseudo-sieboldianum which showed their maximum chlorophyll content in June, A. negundo, which showed the highest chlorophyll content of the four species, exhibited its maximum chlorophyll content in July, whereas September in the case of A. ginnala. The fluctuation of chlorophyll content was similar to that of air temperature, and it increased till July. But chloprophyll content showed a significant relationship in early stage of leaf development, and there could be any interdependence between them in accordance with the seasonal change, no longer. In all four species light compensation points decreased in accordance with the seasonal change, and the maximum photosynthetic rates were obtained in August. Respiratory rates were shown no significant difference among species, and they decreased according to the adbance of season.

• Fashion & Textile Research Journal
• /
• v.11 no.5
• /
• pp.833-839
• /
• 2009

This study was to investigate the human's physiological responses and subjective sensations with wear trial through seasonal condition by age. Climate chamber was set $5^{\circ}C$, RH 45% for winter and $30^{\circ}C$, RH 65% for summer condition. Thirty male subjects were volunteered consisted of 10 people in their 20s, 40s, and 60s. In this study physiological responses such as rectal temperature, skin temperature, clothing microclimate, heart rate and blood pressure were measured. As for age, 60s was the highest in rectal temperature regardless of seasonal condition. In skin temperature, 40s was the highest in winter and 20s was the highest in summer. In clothing microclimate temperature and heart rate, 20s was the highest regardless of seasonal condition. And blood pressure was appeared the highest in 20s regardless of seasonal condition. Subjective sensations such as temperature sensation, wetness sensation and thermal comfort were measured. The subjects revealed that temperature sensation was higher 20s than 60s. Compare of other age group, 60s felt colder in the same environment and clothing. It suggested that temperature susceptibility in 60s became weakened showing no change sensation during the cold exposure. Wetness sensation was higher 20s than 60s. Thermal comfort of 60s was felt more discomfortable than any other age group. This means require the supplement of a suitable clothing in order to adjust to change of environmental conditions.

• Asian-Australasian Journal of Animal Sciences
• /
• v.21 no.12
• /
• pp.1779-1784
• /
• 2008

Seasonal changes in the concentration of free amino acids were determined monthly in plasma from the jugular blood of 50 thoroughbred racehorses that compete during the night between June and September and during the day between October and January. The concentration of most free amino acids remained relatively constant between June and January. However, those of glutamic acid, alanine, isoleucine and lysine tended to decrease and that of arginine (Arg) significantly decreased between July and September. The concentration of methionine (Met) gradually increased between June and September and significantly decreased thereafter. The concentration of 3-methylhistidine (3-MH) significantly increased between July and September and decreased thereafter. There were significant correlation between 3-MH and Arg. In conclusion, this study provided evidence of significant seasonal change in plasma 3-MH, Arg and Met of racehorses, and this was considered to relate to an environmental effect. Moreover, our study is the first to show 3-MH in plasma of racehorses affected by environmental change.

• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.34 no.5
• /
• pp.51-58
• /
• 2018

The purpose of this study was to analyze the effect of seasonal change in characteristics of hygiene activity on domestic hot water energy consumption. With 16 residents of 4 households, the data about frequency of hygiene activity and water temperature was collected from February to August, 2017. The results of collected data discovered that the frequency of hygiene activity was higher especially in summer, whereas the consumption of warm water they used was higher in winter. The seasonal change in characteristics of hygiene activity was analyzed to be changed and strongly influenced by outdoor temperature. The influence of characteristics of hygiene activity on hot water consumption was analyzed. There was 13% of difference between consumption that was calculated taking characteristics of hygiene activity into account and consumption that was not. Therefore, this study suggested hygiene activity schedule, hot water profile and hot water consumption pattern, which can be utilized for improving simulation as well.

• Journal of the Korean Geographical Society
• /
• v.41 no.4 s.115
• /
• pp.435-456
• /
• 2006

This study examines the long-term spatial patterns and recent trends of seasonal onsets and durations defined by daily temperatures in South Korea for the period 1973-2004. Spatially, spring and winter onset dates show approximately 44 day and 63 day maximum difference respectively between south and north (Seongsanpo to Daegwallryeong) attributable to the impacts of latitudes and altitudes. In contrast, summer onset, which is more affected by proximity to oceans and altitudes than by latitudes, begins earlier in interior low elevated areas than in the coastal areas but earliest at higher latitudes than Jeiu Island. Five climatic types regarding the seasonal cycles in South Korea are spatially clustered according to the combination of longer seasonal durations. As a reflection of recent climate changes on seasonal cycles in South Korea, winter duration was shortened by 10 days during the post-1988 period due to a late winter onset of 4 days and an early spring onset of 6 days. The winter reduction began in the southern regions of the Korean Peninsula in the mid-1980s and spread northward during the 1990s period, ultimately appearing everywhere. In urbanized cities, where much of the surface is covered with asphalt or concrete, the winter reduction was intensified and summer duration was locally incremented. The reduced winter duration in recent decades shows significant teleconnections with variations of geopotential height (925hPa) in the eastern Arctic region ($0-90^{\circ}E$, $65-85^{\circ}N$) during the cold season. The reduction in winter duration in South Korea agrees with results in overall global warming trends as a climate change signal.

• The Plant Pathology Journal
• /
• v.36 no.5
• /
• pp.406-417
• /
• 2020

Early warning services for crop diseases are valuable when they provide timely forecasts that farmers can utilize to inform their disease management decisions. In South Korea, collaborative disease controls that utilize unmanned aerial vehicles are commonly performed for most rice paddies. However, such controls could benefit from seasonal disease early warnings with a lead time of a few months. As a first step to establish a seasonal disease early warning service using seasonal climate forecasts, we developed the EPIRICE Daily Risk Model for rice blast by extracting and modifying the core infection algorithms of the EPIRICE model. The daily risk scores generated by the EPIRICE Daily Risk Model were successfully converted into a realistic and measurable disease value through statistical analyses with 13 rice blast incidence datasets, and subsequently validated using the data from another rice blast experiment conducted in Icheon, South Korea, from 1974 to 2000. The sensitivity of the model to air temperature, relative humidity, and precipitation input variables was examined, and the relative humidity resulted in the most sensitive response from the model. Overall, our results indicate that the EPIRICE Daily Risk Model can be used to produce potential disease risk predictions for the seasonal disease early warning service.

• Journal of Plant Biology
• /
• v.29 no.2
• /
• pp.95-107
• /
• 1986

Seasonal changes in pool size, inflow rates in biomass and phosphorus, and the efficiency of phosphorus use in the stand of three populations (Helianthus tuberosus, Artemisia princeps and Phalaris arundinacea) in the basin of the Mt. Geumoh were investigated. During the early growing period, in the three species populations the relative size of the phosphorus pool of population was larger then that of its biomass pool, but that of the phosphorus pool of belowground part decreased more rapidly than that of its biomass pool. In the A. princeps and P. arundinacea populations, the phosphorus inflow rate was markedly high during the soil thaw in early spring and its seasonal change pattern was different from that of the biomass production rate, showing two peaks in March and June. But in the H. tuberosus population, the two seasonal change patterns were alike. The annual biomass production was 2283 gDM m-2 in the H. tuberosus, 1884 m-2 in the A. princeps and 1879 gDM m-2 in the P. arundinacea population, and the annual phosphorus inflow was 11.35, 9.63 and 7.60 gP m-2, respectively. The P. arundinacea population showed the smallest LAI peak(5.4 in early June), and the largest NAR peak (36.9 gDM m-2wk-1) RGR peak (0.15g g-1 wk-1) among the three species populations. The seasonal change patterns in whole plant EPU of the three species populations showed the bell shape, but the annual EPU values among them were markedly different. It was noticed that the population with the highest RGR showed the highest EPU among the three species populations while the population with the lowest RGR showed the lowest EPU among them.

• Ocean and Polar Research
• /
• v.23 no.4
• /
• pp.433-440
• /
• 2001

Marine organisms in Antarctica live in an environment which exhibits variability in physical processes over a wide range of temporal scales, from seconds to millennia. This time scale tends to be correlated with the spatial scale over which a given process operates, though this relationship is influenced by biology. The way organisms respond to variability in the physical environment depends on the time-scale of that variability in relation to life-span. Short-term variations are perceived largely as noise and probably have little direct impact on ecology. Of much greater importance to organisms in Antarctica are seasonal and decadal variations. Although seasonality has long been recognised as a key feature of polar environments, the realization that decadal scale variability is important is relatively recent. Long-term change has always been a feature of polar environments and may be a key factor in the evolution of the communities we see today.