• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.5
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• pp.181-190
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• 2019

In high school classrooms, it is reported that ventilation is often insufficient, increasing health risks among students. Therefore, indoor air quality in school classrooms is very important in terms of students' health and learning abilities. In this study, the effect of window opening, which is a control mechanism for air control in summer high school classrooms, on the change in air and indoor environment of the classroom was analyzed and physical conditions of indoor and air environment were observed during the classroom course, and satisfaction of the students and teachers was assessed with questionnaires. It was found that change rate of $CO_2$ concentration in classroom was effectively reduced by carrying out activity of opening the window by active environment control activity of occupants at break time, intermission time and cleaning time. And optimal window opening by students was presented to prevent unpleasantness and degradation of indoor air quality and the effects were analyzed.

• Journal of Korean Medical classics
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• v.12 no.1
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• pp.168-195
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• 1999

The hakgil is the important disease in the oriental medicine historically. In the preseant time also this disease continually appear all over the world. So purpose of this study is that consider the symptoms and pathogenesis of hakgil(瘧疾) with the point of view of oriental medicine. And in this study, the results are summarized as the followings. 1. The symptos of hakgil(瘧疾). 1) Rigor and heat spasm : The main symptoms of hakgil is the severe and periodical rigor and heat spasm. Generally the rigor first appear and later the heat spasm appear. According to the first and last, severe and weak, the hakgil is classified to hanhak(寒瘧), onhak(溫瘧), danhak(癉瘧), binhak(牝瘧). 2) The regulation of the time of spasm : The spasm occour in the same time daily or one time in two days, three days or several days. And the spasm time is regulary in day or night. 3) The term between the spasm and next one become later or faster. It can be decided that the becoming worse and better in the disease with the signs. 4) The seasonal property Generally the hakgil appear in summer and early autumn. 5) The other kind of hakgil there are five-organ hakgil(五臟瘧), six-kyung hakgil(六經瘧), janghak(瘴瘧), kuihak(鬼瘧), six-gi hakgil(六氣瘧), damhak(痰瘧), sikhak(食瘧), and so on. 6) The pulse condition of the hakgil is chiefly hyun(弦). 2. The pathogenesis of the hakgil 1) The cause of the hakgil The causes of the hakgil first are the seo(暑) or heat(熱) that make the problem in the cycle of five phases(五行). In the consequence, il open the hole of skin so that the pathogenic factors easily invade the humanbody and at the same time the pathogenic factor in the inside easily come out, that make the spasm. In the second time the pathogenic factor of yin(陰) - wind(風), cold(寒), water(水) invade through the opened skin to combine with the factor in the inside. Such condition make the hakgil and the accessory spasm. 2)The pathogenesis of hakgil(瘧疾) (1) The rigor and heat spasm of hakgil(瘧疾) appear because in summer the human body don't accomplish a task of summer because of hot weather or heat, so in autumn the ki(氣) of human body separate into yin(陰) and yang(陽), and the skin of human body is weaken so the saki(邪氣: pathogenic factors) is easily come into the human body. At this time the circulation of ki(氣) is obstructed, so the jungki(精氣: vital substance) apply to straighten the circulation of ki(氣), if the jungki(精氣: vital substance) help the yin(陰) the rigor spasm appear in the opposit direction the jungki(精氣: vital substance) help the yang(陽) the heat spasm appear. (2) The period of circulation of ki(氣) and jungki(精氣: vital substance) is one day, so the general period of spasm of hakgil(瘧疾) is one day, But if the saki(邪氣: pathogenic factors) come into the human body deeply, the jungki(精氣: vital substance) cannot apply 10 straighten the circulation of ki(氣) every day so the period of spasm become longer.

• Current Research on Agriculture and Life Sciences
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• v.31 no.1
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• pp.61-64
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• 2013

This study identified the effect of night time temperatures on the flowering period of spray-chrysanthemum during the summer season in South Korea. According to the results for 2005, the temperature at night time sustained more than $25^{\circ}C$ for 23.6 days during the short day period and delayed the flowering period for 22 days. Similar observations were reported in 2006, as the night time temperature sustained more than $25^{\circ}C$ for 23.6 days during the short day period and delayed flowering period for 23 days. The results for 2007 year showed that night time temperature sustained more than $25^{\circ}C$ for 31.9 days during the same period and delayed flowering for 31 days. In conclusion, based on the results for 2005 to 2007, a specific correlation was found between high night time temperatures and a delayed flowering period for the 'Euro' spray-chrysanthemum.

• Journal of Korean Society of Transportation
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• v.30 no.6
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• pp.3-12
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• 2012

Additive willingness-to-pay (WTP) for leisure-travel time saving focused on the Iksan-Pohang Expressway and the Donghae Expressway was surveyed during the summer months to estimate the value of travel-time savings (VTTS) for non-business leisure trips. Travelers traveling between 2 and 3 hours on Iksan-Pohang Expressway had WTP of 723 won per 10 minutes of leisure-travel time savings and those traveling between 3 and 4 hours on Donghae Expressway had WTP of 854 won per the same. Based on this survey, we learned that WTP in leisure travel time savings increased with the total travel time. 300 effective samples for each expressway were collected, and estimation was separately conducted on the basis of Cox test.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.590-596
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• 1999

The effect of evaporative cooling in alleviating seasonal variations of dairy cows raised in AlMarai Dairy Farms in the Kingdom of Saudi Arabia were studied using milking record collected during the period of 1991 to 1996. The data included 13303 and 8137 records represented winter and summer calving seasons. Evaporative cooling system improved production for cows calved in summer. The least square means of milk yield were 9631 and 9556 liter for cows calved in winter and summer seasons but no significant differences (p<0.05) were observed between the yield of two seasons. No significant effect of season on calving under evaporative cooling on most of the biweekly points of the lactation curve. The farm, parity and milk level showed a significant effect on the shape of the curve. Functions of the lactation curve like initial yield, 305 MY, peak yield, time of peak and duration were estimated for each phase of the lactation curve.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.3
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• pp.439-447
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• 1992

Eight healthy Holstein bulls, 4-6 years old were used to study the effect of season of the year on the biophysical characteristics of semen. Semen was collected twice a week by AV (artificial vagina) over one-year period. The analyses revealed that all the basic seminal traits studied were differed significantly due to season, except the ejaculate volume and consistency and the percentage of swollen spermatozoa in a hypo-osmotic fructose-citrate solution. Ejaculates collected during hot summer season had significantly lower sperm motility, concentration and total counts, and higher percentage of dead spermatozoa than those collected during winter time. Warm spring had moderate semen quality. The temperature-humidity index was calculated and it was associated (p < 0.01) negatively with the ejaculate pH, sperm concentration and total counts, and positively with the % of dead sperms. Ejaculate volume, percentage of swollen spermatozoa, individual motilities did not correlate significantly with the change in temperature-humidity index values. The total live, motile spermatozoa per ejaculate during both the winter and spring seasons showed significant increase of about 37% and 32% respectively over the summer season. Also, rectal temperatures of the bulls were elevated during the hot summer season, while the values of blood hemoglobin and packed-cell volume were decreased.

• Journal of Korean Society for Atmospheric Environment
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• v.32 no.4
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• pp.408-421
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• 2016

Day and night sampling for gas and particle phases PAHs were carried out in Seoul to characterize gas and particle phases PAHs concentrations in day and night times. There was no significant difference between day and night time for particle phase PAHs concentrations and phase distribution of PAHs, while, gas phase PAHs concentrations in daytime were about 1/2 of nighttime concentrations in both summer and winter due to photochemical reaction of gas phase PAHs during daytime. A high fraction of cancer risk for PAHs was attributed to particle phase PAHs and the excess cancer risk in winter was higher than in summer. The excess cancer risk level of total(gas+particle) PAHs in summer was partially observed when both gas and particle phase PAHs concentrations were considered as risk assessment. Based on the diagnostic ratios and factor analysis of PAHs concentrations, combustion(coal and natural gas) and vehicular emission might be the most significant contributors of PAHs and major factors for determining of PAHs concentration were different between day and night times.

• KIEAE Journal
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• v.10 no.4
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• pp.59-66
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• 2010

Natural ventilation is major strategy of 'sustainable building'. It aims to supply fresh air to the indoor, and to remove heat from the indoor during summer. In the latter point of view, natural ventilation can be grouped into two main strategies, daytime ventilation and night cooing. If we take advantage of these two natural ventilation strategies, indoor thermal comfort can be significantly improved. This study focused on grasping the current situation and problem of indoor thermal comfort of the naturally ventilated residential buildings to seek for direction of later studies. Additionally, thermal comfort of residence where the interior blind and exterior insulation were applied was analyzed. It was analyzed that the percentage of the time which satisfy the indoor acceptable operative temperature during summer was 90 ~ 95% and the heat control performance of natural ventilation has a limitation. When the interior blind and exterior insulation were applied, indoor thermal comfort was significantly improved. However, it still need more improvement.

• KIEAE Journal
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• v.6 no.1
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• pp.57-62
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• 2006

Korean Traditional houses has been evolved and developed in many years, adopting the natural environment to control exterior conditions. These control method are various passive system of using natural materials, considering micro climate, building lay out, and these system are more natural and ecological to make the comfortable indoor climate than active systems of the present houses. This study aims to analyzed control performance of outdoor environment of five Korean traditional houses during the summer and winter. These houses are varied with lay out and floor plan to reflect the way of control for environmental condition, surveyed the reverberation time and sound level difference between rooms of the main living room and other main floored room, master room and kitchen. Especially air temperature and humidity have been measured simultaneously in each rooms to compare with outdoor condition. As a result, the variation of air temperature and humidity of most rooms are considerably static while condition of outdoors are much varied, it is showed that indoor climate has been controled with traditional soiled walls.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• v.22 no.1
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• pp.24-32
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• 1994

A special upper-air observation including airsonde and pibal observations was performed to investigate the characteristics features of the vertical distribution of the meteorological elements over Taegu on a selected clear day of each season from October 1991 to August 1992. The diurnal and seasonal variations of the vertical profiles of air temperature and mixing ratio were obtained from airsonde observations and wind speed and direction from pibal observations. The results of these special upper-air observations are as follow : The diurnal variation of the vertical distribution of air temperature reveals the characteristic features associated with the atmospheric boundary layer. All case days, except for the summer season, show upper-level inversion layer which influenced by surface high, and surface inversion layer produced by radiative cooling. The diurnal variation of mixing ratio shows the maximum vale at 1500 LST in both the upper and low levels, and is larger on the lower level than the upper level. The mixing ratio of the lower level is larger than that of the upper level. On the average the mixing ratio decrease with the height, and is the wettest on the summer case day and the driest on the winter case day. The diurnal variation of the wind velocity and direction are variable in the lower level with time and height, while they are steady in the upper level. On the average, the wind direction is southerly or southeasterly for the summer case day, westerly or northwesterly for the spring and fall case days, and northerly or northwesterly for the winter case day.