• 물과 미래
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• 제29권5호
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• pp.203-214
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• 1996

물수지향의 정량적 평가는 수문학의 기본이 되는 중요한 개념이다. 물수지는 수자원의 실태 파악과 기후 변화를 포함한 환경 변화를 이해하기 위하여 그 중요성이 인식되고 있다. 본 논문은 인공위성 자료로부터 얻을 수 있는 식생자료를 근거로 하여 물수지향을 평가하기 위한 방법을 제안한다. 본 연구에서는 NOAA/AVHRR 자료로부터 얻어지는 식생지표 NDVI를 이용하여 직접 실제증발산량을 구하는 방법을 개발하여 그 결과로서 한반도 전역에 대한 물수지해석을 수행한다. 증발산량, 유출률, 과잉수분량과 부족수분량의 공간적 분포를 NDVI와 간략한 물수지모형으로 이용하여 얻고 있다. 이 방법을 이용함으로서 충분한 지상자료를 얻을 수 없는 북한지역을 포함한 한반도 전역에 대한 수문학적 문제의 논의가 가능하게 된다.

• 한국환경과학회지
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• 제12권2호
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• pp.133-137
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• 2003

The Yellow River delta is an important region where coastal and newly formed wetlands distribute in north China. Based on satellite remote sensing images and GIS techniques, this paper tends to delineate the dynamic changes of newly formed wetland in the Yellow River mouth from 1986.5 to 1996.10. Our results show that the newly formed wetland increased by 24.9 $\textrm{km}^2$ per year. Before 1990. 1 and it decreased by 2.40 $\textrm{km}^2$ per year after that. The northern and southwestern parts of the Yellow River mouth are main positions of decrease and the southern and the estuary parts are main positions of increase. The advancing rate of river mouth extending into the Bo Sea is decreasing obviously. The reason for that is the decreasing of water and sediments in the Yellow River, which caused by the increasing use of water and soil conservation on upper reach.

• 한국주거학회논문집
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• 제24권1호
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• pp.51-59
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• 2013

This study aims to improve the thermal comfort level of detached housing area by reducing the impact of thermal environment. The study focused on reducing surface temperature that is generated in buildings and adjacent spaces as a result of sensible heat load and presented a proposal on implementing planting method considering its outdoor condition and structure and composed materials. To perform the study, we utilized 3D-CAD to examine the outdoor condition and structure and composed materials that impact on surface temperature and conducted space design after reflecting climatic elements in simulations. The result is as follows. In reviewing temperature distribution of Heat Island Potential (HIP) of buildings and adjacent spaces, in case where green coverage ratio is increased, there was a $6^{\circ}C$ temperature difference and in regard to changes in the thermal environment in detached housing area, in case where rooftop planting, surface improvement, planting, and overall green coverage ratio is increased, there was a $10^{\circ}C$ temperature difference. In addition, there was difference in temperature in detached housing area following the changes in wind.

• Ocean and Polar Research
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• 제24권2호
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• pp.167-175
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• 2002

Sediment from six piston cores from the East Sea (Sea of Japan) was analyzed for evidence of paleoceanographic changes and paleoclimatic variation. A distinct geochemical boundary is evident in major element concentrations and organic carbon content of most cores near the 10-ka horizon. This distinctive basal Holocene change is interpreted to be largely the result of changing sediment sources, an interpretation supported by TiO_2/Al_2O_3$ ratios. Organic carbon and carbonate contents also differ significantly between the Holocene and glacial intervals. The C/N ratio of organic matter is greater than 10 during the glacial period, but is less than 10 for the Holocene, suggesting that the influx of terrigenous organic matter was more volumetrically important than marine organic matter during glacial times. The chemical index of weathering (CIW) is higher for the Holocene than the glacial interval, and changes markedly at the basal Holocene geochemical boundary. Silt fractions are higher in the glacial interval, suggesting a strong effect of climate on silt particle transportation: terrigenous aluminosilicates and continental organic carbon transport were higher during glacial times than during the Holocene. Differences in sediment composition between the Holocene and glacial period are interpreted to have been climatically induced.

• 한국의류산업학회지
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• 제2권5호
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• pp.405-410
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• 2000

The effects of individual sweating rates on thermophysiological responses during the decrease phase of clothing surface temperature (Tcs) with cotton (C) and polyester (P) clothed subjects were examined. Seven women subjects were exposed in a climatic chamber at ambient temperature of $27.2^{\circ}C$, relative humidity of 50%, and their lower-legs were immersed in a water bath at a temperature of $35-41^{\circ}C$ for 70 min. During water immersion, Tcs in C-clothed subject rose immediately after the onset of sweating and then Tcs fell gradually. In C-clothed subjects, Tcs decreased directly (p<0.05) in proportion to total sweating rate (TSR), however no significant correlation was observed in P-clothed subjects. The relationship between TSR and changes in mean skin temperature, and skin blood flow showed negative correlation when wearing C-clothing (p<0.05), however, no significant correlation when wearing P-clothing. Individual TSR was correlated with threshold rectal temperature for sweating onset (p<0.05) with C- and P-clothed subjects. The results showed that individual TSR had significant effects on not only Tcs but also on thermoregulatory responses during the Tcs decrease phase.

• 한국정밀공학회지
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• 제32권2호
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• pp.185-190
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• 2015

This paper presents a new method to determine sensitivity coefficients of temperature and humidity of torque transducers by using a natural and seasonal variation of ambient conditions at the laboratory. We had measured the sensitivities of the torque transducers over almost one year using the KRISS 2 kN m torque standard machine. The sensitivity data acquired at various ambient conditions were processed using our measurement model to extract the sensitivity coefficients of temperature and humidity simultaneously with high precision. A comparison with a previous method using an environmental control chamber was carried out to test the feasibility of using our new method. Two results agreed within the uncertainty. We revealed that the torque measuring errors could be 8 times higher than the measurement and calibration capability of KRISS torque standard machine if the sensitivity changes due to the temperature and humidity are not properly corrected during a calibration.

• 한국물환경학회지
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• 제26권1호
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• pp.133-139
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• 2010

Global human activities associated with the use of fossil fuels have aggravated climate change, increasing air temperature. Consequently, climate change has the potential to alter surface water temperature with significant impacts on biogeochemical cycling and ecosystems in natural water body. In this study, we examined temporal trends on historical records of surface water temperature, and investigated the air temperature/water temperature relationship and the potential water temperature change from an air temperature scenario developed with regional climate model. Although the temporal trends of water temperature are highly variable site-by-site, surface water temperature was highly dependent on air temperature, and has increased significantly in some sub-watersheds over the last two decades. The results presented here demonstrate that water temperature changes are expected to be slightly higher in river system than reservoir systems and more significant during winter than summer for both river and reservoir system. Projected change of surface water temperature will likely increase $1.06^{\circ}C$ for rivers and $0.95^{\circ}C$ for reservoirs during the period 2008 to 2050. Given the potential climatic changes, every $1^{\circ}C$ increase in water temperature could cause dissolved oxygen levels to fall every 0.206 ppm.

• Safety and Health at Work
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• 제11권1호
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• pp.1-9
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• 2020

Background: As the impact of climate change intensifies, exposure to heat stress will grow, leading to a loss of work capacity for vulnerable occupations and affecting individual labor decisions. This study estimates the future work capacity under the Representative Concentration Pathways 8.5 scenario and discusses its regional impacts on the occupational structure in the Republic of Korea. Methods: The data utilized for this study constitute the local wet bulb globe temperature from the Korea Meteorological Administration and information from the Korean Working Condition Survey from the Occupational Safety and Health Research Institute of Korea. Using these data, we classify the occupations vulnerable to heat stress and estimate future changes in work capacity at the local scale, considering the occupational structure. We then identify the spatial cluster of diminishing work capacity using exploratory spatial data analysis. Results: Our findings indicate that 52 occupations are at risk of heat stress, including machine operators and elementary laborers working in the construction, welding, metal, and mining industries. Moreover, spatial clusters with diminished work capacity appear in southwest Korea. Conclusion: Although previous studies investigated the work capacity associated with heat stress in terms of climatic impact, this study quantifies the local impacts due to the global risk of climate change. The results suggest the need for mainstreaming an adaptation policy related to work capacity in regional development strategies.

• 한국전기전자재료학회논문지
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• 제31권1호
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• pp.24-28
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• 2018

Insulators used in overhead transmission lines are continuously exposed to a number of mechanical and electrical stresses owing to external environmental factors, resulting in corrosion, reduction in durability, and deterioration. Widely used porcelain insulators are fabricated with cement and porcelain and are especially common in Korea. Changes in the hardness and chemical reactivity of the cement increase the leakage and fault currents and increase the possibility of flashover due to insulation breakdown. Therefore, it is important to evaluate the durability and defects of porcelain insulators. Studies on the reliability of various evaluation methods are needed to prevent accidents by accurately determining the replacement timing and potential defects in porcelain insulators. In this study, the hardness of the cement part of the porcelain insulator was measured using the Vickers hardness test and its composition was analyzed by energy dispersive spectroscopy and X-ray diffraction analysis. The performance of the insulators was compared in two different regions with varying climatic conditions. This study presents an evaluation method of the defects in porcelain insulators by measuring humidity, which can also be used to assess the reliability of the insulators.

• Wind and Structures
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• 제37권2호
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• pp.95-104
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• 2023

The latest revision of AS/NZS 1170.2 incorporates some new research and knowledge on strong winds, climate change, and shape factors for new structures of interest such as solar panels. Unlike most other jurisdictions, Australia and New Zealand covers a vast area of land, a latitude range from 11° to 47°S climatic zones from tropical to cold temperate, and virtually every type of extreme wind event. The latter includes gales from synoptic-scale depressions, severe convectively-driven downdrafts from thunderstorms, tropical cyclones, downslope winds, and tornadoes. All except tornadoes are now covered within AS/NZS 1170.2. The paper describes the main features of the 2021 edition with emphasis on the new content, including the changes in the regional boundaries, regional wind speeds, terrain-height, topographic and direction multipliers. A new 'climate change multiplier' has been included, and the gust and turbulence profiles for over-water winds have been revised. Amongst the changes to the provisions for shape factors, values are provided for ground-mounted solar panels, and new data are provided for curved roofs. New methods have been given for dynamic response factors for poles and masts, and advice given for acceleration calculations for high-rise buildings and other dynamically wind-sensitive structures.