• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.43-44
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• 2002

중국 서북건조 사막지역에서 봄철에 기온이 올라가면서 강한 한랭전선을 동반한 저기압이 발달할 때 그 전선 후면에 미세한 모래먼지가 바람에 휘감겨 올라가 황사가 발생한다. 발원지에서 생성된 황사는 약 30%가 발원지에서 재 침적되고, 20%는 주변지역으로 수송되며, 50%는 편서풍을 타고 1,500-2,000km이상의 거리를 이동하여 우리나라, 일본 및 하와이에까지 침적되는 것으로 알려져 있다. (중략)

• Korean Journal of Ecology and Environment
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• v.53 no.2
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• pp.195-207
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• 2020

In Korea, specific thermal elements such as annual mean temperature (AMT) 13℃, 14℃, and Kira's coldness index (CI) -10℃, have been suggested about the northernmost distribution of the warm-temperate evergreen broad-leaved forest zone. We reviewed the relationship between three thermal elements and the actual distribution of evergreen broad-leaved woody plants or its communities. Thiessen and Kriging method using point-data calibrated by seasonal lapse rate according to altitude were utilized for the spatial distribution pattern analysis. Several phytoclimatic maps were also produced in order to compare different thermal values. We identified that the AMT 13℃ was the best thermal element to demarcate the northern limit of the warm-temperate forest zone. Its area was estimated ca. 20,334 ㎢ and larger than those of other thermal elements. We concluded that an indirectly fabricated index i.e. CI -10℃ is useless and it was enough for a direct value of AMT 13℃ to represent the northern-limit distribution of warm-temperate forest zone, at least in Korea. Further researches on the reciprocity between floristic regions and phytoclimate zones are raised.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.545-556
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• 2003

Detailed interdisciplinary investigations demonstrate that the Yeongsan River estuarine-filled sediments clearly record important paleoenvironmental changes during the Last Glacial and Holocene. The sediments from 18.9 m(20.5∼l.6m in depth) long core MW-1 are differentiated by changes in sedimentary textures and palynomorph assemblages. Chronology was provided by AMS$^{14}$C dating and regional pollen correlation. Three paleoenvironrnental phases are recognized: (1) The Last Glacial deposits consist mainly of fluvial sediments and paleosols, experienced deposition alternating with pedogenesis. The appearance of the paleosols suggests that the paleoclimate might be cold and humid. (2) The early and middle Holocene phase started abruptly in response to the rapid global climatic warming. and is characterized by abundant marine palynomorphs. (3) The late Holocene is marked by more cool conditions. The paleoenvironmental changes recorded in the sediments coincide not only with local but also with broad-scale, probably global climate changes.

• Journal of The Geomorphological Association of Korea
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• v.18 no.3
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• pp.121-129
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• 2011

This work is to elucidate in typological aspect main geomorphological processes in the morphogenetic system of Mongolian steppe zone. Its morphogenesis manifest interaction of intense gelifraction and active erosion either by slope run-off or by wind. Intense gelifraction owes both to cold temperature regime with great amplitude, and to moisture associated with snow fall. Erosion of material produced by gelifraction is assured by surface run-off of summer rainfall and spring eolian activities. The geomorphological landscape sculptured by such morphogenetic processes manifest low-relief smooth slopes. This feature reveals that intense gelifraction keeps abreast with removal of weathering product by surface run-off and wind.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.7
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• pp.963-968
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• 1998

A study was conducted to investigate the effect of cooling hands of feet on human thermoregulation in the cold. Eight young (22$\pm$1 yr) and eight aged (69$\pm$4 yr) men volun-teered as subjects They stayed at 1$0^{\circ}C$ in the supine posture during the experiment which included hands or feet exposure to the air for 20 minutes. Hand Exposure (HE) and Foot Exposure (FE) were conducted in radomized order and the baseline was kept before HE and FE. Core temperatures, limb skin temperatures adn thermal sensations were measured. Obtained data were analyze using t-test and correlation. Rectal and esophageal tem-peratures increased in the young (YG) and in aged (AG). Change rate of esophageal temperature (Tes) was maintained higher during FE than HE while rectal temperature showed no differences between YG and AG, and between HE and FE. Hand and foot skintemperature in YG and AG decreased similarly during HE and Fe. Forearm skin temperature during HE decreased while leg skin temperature during FE showed no change HE and Fe. It was concluded that the lower cooling. Furthermore, the increase of Tes was greater in young men than aged men. It is also suggested that the wearing behavior can be differently modified between young and aged men.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.42-43
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• 2018

The research is to suggest the compensating strength values depending on various managing periods of concrete based on the strength development model calculated with equivalent age method for 20% of blast furnace slag replaced concrete. As a result, for 28 days of managing period, 9, 6, and 3MPa of compensating strength values were suggested when the temperatures were from 4 to 6℃, from 6 to 12℃, from 12 to 17℃, respectively. Additionally, for 42 days of managing period, 6 and 3MPa of compensating strength value was suggested when the temperature was from 4 to 7℃, from 7 to 12℃, and for 56 days of managing period, 3MPa of compensating strength value was suggested when the temperature was from 4 to 9℃. Furthermore, for 28, 42, 56, and 91 days of managing periods, any compensating strength values were needed when the temperature were higher than 17, 12, 9, and 4℃, respectively.

• The Korean Journal of Quaternary Research
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• v.3 no.1
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• pp.35-45
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• 1989

In Korean peninsula as well as in Western European Countries, we can find, reddish bands in sandy deposits of various origin. These bands (called "$B_t$ Band"), composed of fine material, are regularly intervalled and parallel to topography. This study is tring to elucidate their origin and associated milieux, with a group of methods and techniques (field survey, micromorphological analysis, granulometry, X-ray diffractometry of clay minerals...). $B_t$ Bands are not sedimentological origin. They were formed by superposition of two type accumulations in the sandy profile, triggered by different mechanisms: 1) accumulation in banded form, concerning silty heterometric material and micas, oweing to cryophoretic forces operating in course of deep freezing of sandy deposits: 2) illuviation of ferrugineous clays in the precedants bands, migrated in chelate state by soil water. The first processes are associated with very cold and humid climate in which freeze soil more than 3m in depth. The second, cold and humid climate in which podzolizattion is generalized. In case of South Korea and Western Europe, these two types of climates are not present circumstance, but Recent Quaternary (probably since the Wurm).the Wurm).

• Journal of the Korean GEO-environmental Society
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• v.18 no.1
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• pp.5-12
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• 2017

The damage of the tunnel lining on the cold regions can be represented by cracks and leaks caused by freezing of ground water. However, domestically, the relevant construction guidelines are not provided so far. Thus, in this research, the mechanical behavior and thermal conductivity of designated tunnel area are measured using instrumentation system installed in the lining concrete inside tunnels in order to analysis their behavior with regard to temperature variations. Previous research mainly focused on the effect of temperature on the tunnel lining based on the air and initial ground temperature at urban regions. Thus, this study analyzes effects of air temperature and initial ground temperature of designated tunnel area at the cold regions. The temperature of the groundwater at the backfill of the tunnel lining are analyzed to evaluate the heating element. Numerical analyses are performed to evaluate the heating element with regard to the various initial ground temperatures.

• Fashion & Textile Research Journal
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• v.20 no.4
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• pp.474-481
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• 2018

For this study, we developed clothing in which textile materials that were excellent weather control function for the cold environment and we performed the human subject test with developed clothing to determine the thermal comfort. We used 2 clothing samples developed (A and B, hollow yarn+moisture absorption/quick drying yarn, 3 layers, high stretchable, heat reflection film and lamination treated) and a control sample (Ctrl.) for the human subject test and 8 adult males were used as a human subjects and environmental conditions of chamber were $0{\pm}1^{\circ}C$. $50{\pm}5%RH$, 0.3m/sec. The results were as follows: The average skin temperature and hand, thigh temperature of B were higher than B and Ctrl. (p<.05). The micro-climates of B were near to thermal comfort range which is $32{\pm}1^{\circ}C$ and $50{\pm}10%\;RH$. The chest temperature of B was significantly higher than others (p<.05). The relative humidity of B was lower than others and kept stable rather than others. The thermal sensation of B was near the "neutral" and was significantly different from Ctrl. (p<.01) and the weight loss of B was lower than Ctrl. (p<.05). The counting task and hand temperature was positively related and the counting task value of B and A is bigger than Ctrl. and that of A was bigger than Ctrl. (p<.05).

• Journal of the Korean GEO-environmental Society
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• v.18 no.11
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• pp.35-40
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• 2017

The rearside of concrete lining of tunnels constructed in cold region might experience on freezing due to the low temperature. This causes damage of concrete lining resulting in adverse affect on the durability as well as integrity of tunnel structure by causing damage to the concrete lining. In order to prevent the rearside of tunnel lining from freeing, the temperature change inside the concrete lining was measured by attaching a heating element to the tunnel lining surface and generating heat for a certain period of time. A special freezing chamber was developed to conduct the experiments considering in-situ environment. The carbone nanotube (CNT) was used as a heating element in this study. The temperature distribution of the concrete lining was measured by applying the heat to the heating element. The effect of the outside temperature and heating duration were analyzed.