• Journal of Astronomy and Space Sciences
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• 제35권2호
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• pp.83-92
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• 2018

The summer polar lower thermosphere (90-100 km) has an interesting connection to meteors, adjacent to the mesopause region attaining the lowest temperature in summer. Meteors supply condensation nuclei for charged ice particles causing polar mesospheric summer echoes (PMSE). We report the observation of meteor trail with nearly horizontal transit at high speed (20-50 km/s), and at last with re-enhanced echo power followed by diffusive echoes. Changes in phase difference between radar receivers aligned in meridional and zonal directions are used to determine variations in horizontal displacements and speeds with respect to time by taking advantage of radar interferometric analysis. The actual transit of echo target is observed along the straight pathway vertically and horizontally extended as much as a distance of at least 24 km and at most 29 km. The meteor trail initially has a signature similar to 'head echoes', with travel speeds from 20 - 50 km/s. It subsequently transforms into a different type of echo target including specular echo and then finally the power reenhanced. The reenhancement of echo power is followed by fume-like diffusive echoes, indicating sudden release of plasma as like explosive process probably involved. We discuss a possible role of meteor-triggered secondary plasma trail, such as fireball embedded with electrical discharge that continuously varies the power and transit speed.

• 환경위생공학
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• 제16권3호
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• pp.42-53
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• 2001

This study were conducted to estimate property of nitrogen dioxide concentration at industrial areas in Korea. The nitrogen dioxide concentrations were measured for 50 dwellings at Ulsan and Yeochon, respectively using the nitrogen dioxide filter badge forming the passive sampler from summer time 1998 to winter time 1999. The major results obtained from this study were as follows: 1. The mean indoor, outdoor, and personal concentrations of nitrogen dioxide during summer time 1998 in Ulsan were 28.9 ppb, 24.8 ppb, 24.8 pub, respectively. 2. The mean indoor, outdoor, and personal concentrations of nitrogen dioxide during winter time 1999 in Yeochon were 11.4 ppb, 12.5 ppb, 15.5 ppb, respectively. 3. The mean concentration of nitrogen dioxide during winter time 1998 were higher than the corresponding levels during summer time 1997 in Ulsan. 4. The mean concentration of nitrogen dioxide in Ulsan were in general higher than the corresponding levels in Yeochon. 5. This results in slightly positive correlation among indoor, outdoor, and personal nitrogen dioxide concentrations for summer time in Ulsan, then it statistical significance is showed(p <.05). These results suggest that nitrogen dioxide concentrations in industrial areas seem to be affected by traffic density and conditions of industrialization.

• 복식문화연구
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• 제28권1호
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• pp.131-145
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• 2020

As the population of consumers of outdoor wear expands, there is increasing interest among consumers in trendy lifestyle outdoor. Accordingly, it is essential to develop designs that are drawn from outdoor wear. This can be limited to traditional mountaineering suits, and designs developed from men's outdoor zip-up T-shirts, which are highly utilized in everyday life, are very important. This study developed the design of a summer zip-up T-shirt for men with both functional and aesthetic qualities. Visual images of foreign brands and domestic outdoor-focused T-shirts from the spring/summer seasons of 2013-2019 were collected to analyze the following modeling elements: silhouettes, details, colors, materials, and prints. In addition, the design concept was derived by analyzing presentations from the global outdoor trade Fairs (2013-2019). To develop a sustainable eco-friendly outdoor summer T-shirt for men, the concept was derived according to three categories: eco-friendly, sportism-expressed active elements of sports, and an outro-concept of urban town wear as an outdoor lifestyle. Thus, a total of 12 styles of design were developed. High utilization of the outdoor wear T-shirts (which are also popular as lifestyle wear), is an important aspect of building a segmented lineup of the slow-growing outdoor wear market and supports expansion of the scope of theoretical research on outdoor wear design.

• 대한지리학회지
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• 제41권1호
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• pp.94-105
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• 2006

본 연구에서는 우리나라의 여름과 겨울철의 이상기온 출현 빈도의 변화와 그에 영향을 미치는 요인과의 관계를 파악하고자 하였다. 우리나라의 대부분 관측 지점에서는 여름철 이상고온 출현 빈도의 증가와 겨울철 이상저온 출현 빈도의 감소 경향이 뚜렷하다. 이러한 이상기온 출현 빈도의 변화는 대기 순환 지수 중 겨울철 이상기온 출현에 영향을 미치는 겨울 몬순 지수와 시베리아 고기압 강도 지수 및 북극 진동 지수, 그리고 여름철 이상저온 출현에 영향을 미치는 오호츠크해 고기압 강도 지수와 북태평양 지수 등의 변화 경향과 유사하다. 이 지수들은 이상기온의 변화에 영향을 미치는 요인 중 최근의 지구 온난화 경향을 반영하며 우리나라 전 지역의 이상기온 출현 빈도와 관계가 뚜렷하다.

• 한국환경과학회지
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• 제25권11호
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• pp.1475-1484
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• 2016

To analyze the cooling effect of urban green areas, we conducted micrometeorological measurements in these areas and their surroundings in Seoul, Korea. From the average hourly temperature measurements through each month for the last two years (March 2013 to February 2015), we found that the maximum temperature difference between urban and green areas was about $2.9^{\circ}C$ at 16:00 LST in summer, and the minimum was about $1.7^{\circ}C$ at 22:00 LST in winter. In summer, the temperature difference was the largest during the day, rather than at night, due mainly to shading by the tree canopy. The specific humidity difference between the two areas was about $1.5g\;kg^{-1}$ in summer, and this decreased in the winter. The specific humidity difference between urban and green areas in summer is relatively large during the day, due to the higher evapotranspiration level of biologically active plants.

• 설비공학논문집
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• 제17권5호
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• pp.496-504
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• 2005

Heat recovery ventilators (HRV) are developed in order to satisfy both energy conservation and the improvement of indoor air quality as an alternative for current natural ventilation systems and local mechanical ventilation systems in kitchens and bathrooms. However, the performance of HRV system and the consequent effect on heating and cooling energy saving have not been sufficiently validated quantitatively in case of the application of HRVs in real residences. In this study, field measurement and computer simulation were conducted in both summer and winter period to assess the performance and validate energy conservation effect of HRVs. Under the Korea weather condition, average total heat recovery efficiency was $27\%$ in summer and $46\%$ in winter. According to the field measurement, HRV system can save the energy by $10\%$ in summer and 15$\%$ in winter. Furthermore, according to the simulation assessment, HRV system can save the energy by $17\%$ in summer and $17\%$ in winter.

• 한국의류학회지
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• 제9권2호
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• pp.57-65
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• 1985

In the experiment with a basic material for the design of summer wear that comfort can be obtained in temperature, to get individual differences, clothing styles (slacks, skirt), material differences(T/C, cotton), and the contrast between when naked and dressed, when two healthy females were dressed four kinds of summer wear as an object of experiment under the regular warm temperature environmental condition (24, 28, 32, $36^{\circ}C$, $60\pm10\%$ RH), the measurement of physiological, phychological change was taken and the result goes as follow; 1. Mean skin temperature rose by clothing, body weight loss decreased below $32^{\circ}C$, thermal sensation changed toward low temperature by $2\~3^{\circ}C$. 2. Mean skin temperature, body weight loss, the lowest blood pressure above $32^{\circ}C$, under-clothing temperature, and thermal sensation increased when in slacks to be compared with when in skirt. 3. Ambient temperature had a great effect on mean skin temperature, body weight loss, respiration, clothing surface temperature, under-clothing temperature and humidity, thermal sensation, etc. 4. It was admitted that pulse, thermal sensation, comfort show different individuality. 5. It was recognized that the lowest blood pressure, clothing surface temperature, under. clothing humidity differ according to the kinds of clothing. 6. A comfortable ambient temperature in clothing summer wear was about $27\~28^{\circ}C$.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.333-333
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• 2017

This study was conducted to establish of cropping system for year-round forage crops production in east-southern part of Korea and investigated their productivity and feed values. Cropping systems were tested in experiment using oat (cv. Highspeed and Darkhorse) in spring and autumn season, corn (cv. Kwangpyeongok) and sorghum (ss-450) in summer season and rye (cv. Gogu) and triticale (cv. Joseong) in winter season. Considering the forage productivity and feed value such as acid detergent fiber (ADF), neutral detergent fiber (NDF) and total digestive nutrients (TDN), this result suggest that three cropping system for year-round forage crops production. The combinations with triticale (winter), corn or sorghum (summer) and oat (autumn) were would be suitable ones. And also the combinations with rye (winter), corn or sorghum (summer) and oat (autumn) were would be suitable. If forage crops cultivation was started in spring season, the combinations with oat (spring), oat (autumn), triticale or rye (winter), corn or sorghum (summer) and oat (autumn) were would be appropriable. For the more suitable cropping system, we are proceeding on verification experiment of year-round forage crops.

• Asian Journal of Atmospheric Environment
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• 제8권4호
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• pp.192-201
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• 2014

A comprehensive profile of volatile organic compounds (VOCs) in public spaces is needed for interpreting indoor air measurements. Seasonal differences in profiles are critical for epidemiological study and risk assessment. The purposes of this study were to establish profiles for individual VOCs in 50 indoor public places in Korea and to determine seasonal variations in their concentrations. Air samples were taken during working hours. Seventy-two of the 91 targeted VOCs were identified using multiple standards. Six VOCs detected in all summer and winter samples were toluene, acetone, m,p-xylenes, ethylbenzene, benzene, and styrene. In summer, methyl ethyl ketone and 1-butanol were also found in all samples. In both seasons, the dominant indoor VOCs were toluene, m,p-xylenes, ethylbenzene, acetone, and isopropyl alcohol. Other chemicals associated with gasoline emissions were dominant in summer. Limonene was dominant only in winter due to the consumption of tangerines. The nine VOCs with the highest concentrations comprised 64.8% and 49.6% of the TVOC in summer and winter, respectively. Comparing two types of adsorbent tube, a single adsorbent tube with Tenax-TA had similar detection performance as a double adsorbent tube with Tenax and Carbotrap.

• 대기
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• 제18권4호
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• pp.249-266
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• 2008

The tendencies for teleconnection with a time lag and other characteristics of Korean summer droughts have been investigated and some clues to predict the drought occurrences several months before have been found. First, the May and June droughts in Korea are simultaneous with those over the northwestern part of Korea owing to the relation with the baroclinic wave. However, the July and August droughts occur over the mid-latitudes or southern part of Korea owing to the relation with the Changma front. Second, several months before the MJJA droughts in Korea, it is found that the effective drought index (EDI) over particular areas (hereafter, referred to as the omen areas) is large. Thailand, Carolina Island, Mongolia, and Central Bengal Bay were selected as the omen areas. Third, when the monthly minimum EDI (MME) of the omen area in winter is more than 0.7, it signifies that the precipitation is above normal, Korea has almost always experienced a summer drought. However, the droughts occurring with this type of relationship only represent half of the MJJA droughts in Korea. Fourth, the relationships between the Korean drought and the precipitation over omen areas in low latitudes are not valid over all the eight precipitation areas in Korea, but only over Areas I, II, and III, where heavy rains occur during spring and summer.