• Title/Summary/Keyword: cold environment

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A Study on the Estimation of Vehicle Driving Pattern and Cold Emission Length by using on-board Telematics Devices (텔레매틱스 기술을 이용한 자동차 주행 패턴 및 냉간 배출거리 평가에 관한 연구)

  • Choi, Sang-Jin;Kim, Pil-Su;Park, Sung-Kyu;Park, Gun-Jin;Kim, Jin-Yun;Hong, Young-Sil;Jang, Young-Kee;Kim, Jeong;Kim, Jeong-Soo
    • Journal of Korean Society for Atmospheric Environment
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    • v.29 no.6
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    • pp.734-744
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    • 2013
  • In this study, the telematics device was installed on the car (OBD-II) to collect the information on the operation conditions from each sample vehicle. Based on the information the domestic driving pattern was analysed and the ratio of cold start length was estimated. As a result of analysis for driving pattern, we found a difference in the frequency of driving on the hourly or seasonal basis. Then, the driving pattern of the rush hours, weekdays, and weekends could be derived. Also, from the study, an average of 2.22 times per day occurred in a single trip and average driving distance for the trip was 15.72 km. In addition, the proportion of cold start length was analyzed to be 16.11%. The seasonal cold start length has big difference from season to season (Winter 26.63%, Summer 8.22%, Intermediate 12.65%). There was an inverse relationship between the outside temperature and ratio of cold start length. In order to improve the accuracy of the cold emission estimation, it is necessary to apply domestic ratio of cold start length that driving pattern and temperature in Korea is reflected.

Extreme Climate Analysis and Adaptation Research on the Response of Climate Change in the Inland Region of the Korean Peninsula - Case of Deagu Metropolitan Area - (한반도 내륙 지역의 기후 변화 대응을 위한 극한기후 분석 및 적응 방안 연구 - 대구 광역시 사례를 중심으로 -)

  • Yamada, Keiko;Kim, Hae-Dong;Kim, Eun-Ji;Lee, Soon-Hwan
    • Journal of Environmental Science International
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    • v.29 no.7
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    • pp.773-784
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    • 2020
  • In order to protect the lives and property of citizens, the central and local governments are responding by enacting municipal ordinances and regulations as the frequency of extreme weather conditions due to climate change increases and intensity increases gradually. Accordingly, the basic contents and strategies of domestic and foreign policies to cope with cold and heat waves were reviewed, referring to measures suitable for application to the Daegu metropolitan area. In addition, it is intended to provide a policy alternative to Daegu metropolitan area to minimize damage from extreme weather by identifying the current status, characteristics, and future prospects of extreme weather in Daegu metropolitan area. Since the damage caused by the cold wave in Daegu area is not as great as that of other regions, it is urgent to come up with cold wave measures for the health and transportation sectors, and to come up with measures against the heat wave as the damage caused by the heat wave is the most serious in the country. Also we will identify spatial characteristics so that the districts and counties with high vulnerability to extreme weather can be identified and implemented first, and present civic life-oriented facilities and civic action guidelines to overcome cold and heat waves.

The Adaptability of Korean Farmers to Environment by the Seasonal Fluctuation of Energy Expenditure, Cold and Heat Tolerance (에너지대사의 계절변동과 내한내열성으로 본 한국농업인의 환경적응 능력)

  • Choi Jeong-Wha;Hwang Kyoung-Sook
    • The Korean Journal of Community Living Science
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    • v.17 no.2
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    • pp.49-60
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    • 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.

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Clothing Temperature Changes of Phase Change Material-Treated Warm-up in Cold and Warm Environments

  • Choi Kyeyoun;Chung Hyejin;Lee Boram;Chung Kyunghee;Cho Gilsoo;Park Mikyung;Kim Yonkyu;Watanuki Shigeki
    • Fibers and Polymers
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    • v.6 no.4
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    • pp.343-347
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    • 2005
  • The purpose of this study was to investigate the appropriate amounts of phase change materials to give objective and subjective wear sensations. Vapor-permeable water-repellent fabrics with (WR-PCM) and without (WR) octadecane containing microcapsules were obtained by wet-porous coating process. Then, calculating the area of the WR-PCM treated clothes, we estimated the total calories of the clothing by multiplying the heat of fusion and heat of crystallization of PCM to the calculated area. Wear tests were conducted in both warm environment $(30^{\circ}C,\;65\%\;RH)$ and cold environment $(5^{\circ}C,\;65\%\;RH)$ with sports warm up style experimental garments made with WR and WR-PCM fabrics. Rectal, skin, and clothing microclimate temperatures, saliva and subjective evaluation measurements were done during the wear test. There was no difference of rectal and mean skin temperatures between WR and WR-PCM, but the clothing microclimate temperature of WR-PCM under warm environment was slightly lower than that of WR. In cold environment, WR-PCM showed much higher temperature than in WR. Saliva change did not appear between clothes, but did between two environments. Although subjective sensation between WR and WR-PCM was not significantly different, WR-PCM was rated as cooler than WR in warm environment and as warmer than WR in cold environment. The results of this study indicated that octadecane containing microcapsules in water-repellent fabric provide cooling effect.

Women's Comfort Temperature Range and Dynamic Temperature Change for Maintaining Thermal Comfort in Low Temperature Environment (저온환경에서 여성 온열쾌적성 유지를 위한 쾌적온도범위 및 동적 온도변화 연구)

  • Kim, Soyoung;Lee, Okkyung;Lee, Heeran
    • Fashion & Textile Research Journal
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    • v.22 no.6
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    • pp.853-861
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    • 2020
  • Various types of clothing are being developed to boost thermal comfort during cold winters along with research on change of body temperature when heating is applied. There is a noticeable behavioral difference by gender when using heating panels in a cold environment; however, research on women has been insufficient. This study find a temperature range that provides sustainable thermal comfort in a low temperature environment by observing temperature and change of temperature when subjects are classified according to physical activities or cold sensitivities. For the study results, 8 women in their 20s were subjected to experiment in a low temperature environment for 75 minutes (sitting position: 30 min., running: 15 min., and sitting position: 30 min.). Subjects were asked to turn on/off the heating panel freely to analyze the range of comfortable temperature and clothing microclimate; in addition, skin temperature and heating panel temperature were measured and analyzed at 9 points. As a result, temperature at which subjects turn on and off the heating panel indicated a statistically meaningful difference between the cold sensitivity group depending on exercise or non-exercise. The range of comfortable abdomen temperature was wider than the lower back and was significantly reduced when the subject was running. The range of comfortable temperature was also largest for the heating panel temperature, microclimate, and skin temperature in suggesting that adequate adjustment will be required depending on the surrounding environment or movement of the wearer.

Changes in the Community Structure of Fish Collected by a Gape Net with Wings in the Coastal Waters of Jindo Island in Response to a Cold Water Appearance in the Southwestern Sea of Korea (남해 서부해역 저수온수 출현에 따른 진도 연안 낭장망에 채집된 어류 군집구조 변화)

  • Yoo, Joon-Taek;Seong, Ki Tack;Kim, Yeong Hye
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.5
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    • pp.776-782
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    • 2015
  • We examined the community structure of fish off the coast of Jindo Island in response to a cold water appearance in the southwestern sea of Korea each August between 2013–2015. Using a gape net with wings, we collected 31 taxa during the study period, wherein the most dominant species was Engraulis japonicus. Collichthys lucidus and Neosalanx andersoni, which are mainly distributed in the western sea of Korea, increased in abundance and were dominant in August 2013, possibly due to the apparent intrusion of cold water (< 19°C) from offshore into the coastal waters of Jindo Island. Meanwhile, Scomberomorus niphonius and Sardinella zunasi, which are known as warmwater migratory species, increased in abundance and were dominant in August 2015, likely influenced by the warmer water (> 20°C) at the coast, which resulted in a noticeable lessening of the cold water in the study area. However, no significant differences were observed in fish community structure in the month of August between 2013–1015. This implies that the small-scale spatial and temporal variations in the cold water had limited effects on the fish community structure, even though the abundances of several dominant species varied in the coastal waters.

The effect of acupuncture treated by tonification and sedation manipulation at LI4 and KI7 on lacking of sweating in cold environment(I) (합곡(合谷) 복류(復溜) 보사(補瀉) 시술(施術)이 소한(少汗)에 미치는 영향(影響)(I))

  • Choi, Chan-Hun;Youn, Dae-Hwan;Kim, Young-Sun;Song, Min-Sun;Na, Chang-Su
    • Korean Journal of Acupuncture
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    • v.26 no.4
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    • pp.23-38
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    • 2009
  • Objectives : The purpose of this study was to identify the effect of the tonification & sedation manipulation for LI4 and KI7 on lacking of sweating in cold environment. Methods: The participants were divided into 3 groups as intact group without acupuncture, acupuncture group inserting and twisting with LI4 tonificaton and KI7 sedation method(LI4-tonify KI7-purge) and acupuncture group inserting and twisting with LI4 sedation and KI7 tonificaton method(LI4-purge KI7-tonify). We obtained baseline data at cold condition with the temperature $14{\pm}1^{\circ}C$. After making the participant staying in cold condition for 10 minute, we measured sweating rate in skin surface, body temperature, oxygen saturation, pulse rate, systolic blood pressure, diastolic blood pressure, deoxy-Hb and oxy-Hb in subcutaneous. Results : After acupuncture in cold environment, the sweating rate in skin surface significantly decreased in KI7-purge LI4-tonify group comparing the intact groups. The body temperature significantly increased in LI4-tonify KI7-purge and LI4-purge KI7-tonify groups comparing the intact group. The oxygen saturation significantly increased in LI4-tonify KI7-purge group comparing the intact group. Conclusions : These findings indicated that LI4 tonificaton and KI7 sedation method(LI4-tonify KI7-purge) could be effective for production of sweating in cold condition.

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A Study on Cold Water Damage to Marine Culturing Farms at Guryongpo in the Southwestern Part of the East Sea (경북 구룡포 해역에서의 냉수 발생과 어장 피해)

  • Lee, Yong-Hwa;Shim, JeongHee;Choi, Yang-ho;Kim, Sang-Woo;Shim, Jeong-Min
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.6
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    • pp.731-737
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    • 2016
  • To understand the characteristics and strength of the cold water that has caused damage to marine-culturing farms around Guryongpo, in the southwestern part of Korea, surface and water column temperatures were collected from temperature loggers deployed at a sea squirt farm during August-November 2007 and from a Real-time Information System for Aquaculture environment operated by NIFS (National Institute of Fisheries Science) during July-August 2015 and 2016. During the study period, surface temperature at Guryongpo decreased sharply when south/southwestern winds prevailed (the 18-26th of August and 20-22nd of September 2007 and the 13-15th of July 2015) as a result of upwelling. However, the deep-water (20-30m) temperature increased during periods of strong north/northeasterly winds (the 5-7th and 16-18th of September 2007) as a result of downwelling. Among the cold water events that occurred at Guryongpo, the mass death of cultured fish followed strong cold water events (surface temperatures below $10^{\circ}C$) that were caused by more than two days of successive south/southeastern winds with maximum speeds higher than 5 m/s. A Cold Water Index (CWI) was defined and calculated using maximum wind speed and direction as measured daily at Pohang Meteorological Observatory. When the average CWI over two days ($CWI_{2d}$) was higher than 100, mass fish mortality occurred. The four-day average CWI ($CWI_{4d}$) showed a high negative correlation with surface temperature from July-August in the Guryongpo area ($R^2=0.5$), suggesting that CWI is a good index for predicting strong cold water events and massive mortality. In October 2007, the sea temperature at a depth of 30 m showed a high fluctuation that ranged from $7-23^{\circ}C$, with frequency and spectrum coinciding with tidal levels at Ulsan, affected by the North Korean Cold Current. If temperature variations at the depth of fish cages also regularly fluctuate within this range, damage may be caused to the Guryongpo fish industry. More studies are needed to focus on this phenomenon.

A Study on the Grinding Characteristics according to Oil Mist Supply Method (오일 미스트 분사 방법에 따른 연삭특성)

  • 허남환;이석우;최헌종
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.254-257
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    • 2002
  • As the large Coolant amount used of a machine holds mass serious trouble recently, an environment pollution is increased, and a machine is conquering large specific gravity in an empty cost plane. It is the stage that must reexamine the parts washing that processing is later with this current way or a problem of a liquid waste treatment back. The environmental problems by using coolant demanded the new cooling methods. As one of them, the studies on the grinding with compressed cold air and oil mist have been done. The cooling method using compressed cold air was effective through going down the temperature of compressed air supplied below -$25^{\circ}C$ and increasing the amount of compressed cold air, but had not enough cooling effect due to the low performance of lubrication. Therefore, the cooling methods using oil mist newly were suggested. This method can satisfy both cooling effect and lubrication with only small amount of coolant, also have the benefit in the point of decreasing the environmental pollution. This paper focused on analyzing the grinding characteristics of the cooling method using oil mist. The grinding test according to compressed cold air and oil mist supply direction were done.

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