• 한국산림과학회지
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• 제94권2호통권159호
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• pp.96-102
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• 2005

This study evaluated the chemical characteristics of rainfall and throughfall in Pinus koraiensis and Larix leptolepis forests. We analyzed pH, EC, and concentrations of cations and anions in rainfall, throughfall and stemflow collected from both forest types in the experimental forests of the central Korea. The concentrations of chemical elements were much higher in throughfall and stemflow than in rainfall for both forest types, and were significantly different among the seasons. Comparing the chemical elements between the P. koraiensis and L. leptolepis plantations, there were not significantly differences in throughfall, but the concentrations of almost elements of stemflow in P. koraiensis were almost lower than those in L. leptolepis. For seasonal inputs to the forest floor, more than half of the total input of $Ca^{2+}$, ${NO_3}^-$and ${SO_4}^{2-}$ was observed in spring. This suggests that air pollutants such as NOx and SOx accompanying calcium-rich aeolian Yellow Sand (Asian dust) from China could have an important influence on nutrient cycles in Korean forests.

• 천문학회보
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• 제37권1호
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• pp.70.2-70.2
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• 2012

The night sky in Mongolia is known to be one of the darkest and clearest in Asia. The seasonal dust winds from the Gobi desert, however, might degrade the transparency of the night sky and affect the photometrical quality for astronomical research. In this poster, we present the preliminary results of the first transparency measurement of the night sky in Monglia. The observations are done at Zuunmod located at 25 km south from Ulaanbaatar in 2011 October 26-31. We used a CCD camera (QSI 583s) attached to an 80 mm aperture refractor telescope (William Optics Zentih Star 80 II ED APO). A new supernova, SN2011fe, and a young stellar object, HBC 722, were monitored in order to measure the extinction coefficients. These values in Mongolia are compared with those in other astronomical observatory.

• 천문학회보
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• 제42권1호
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• pp.38.3-39
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• 2017

The N159 and N160 ionized regions in the Large Magellanic Cloud are an important extragalactic star-forming complex. The physical environments and the star formation stages are different in N159 and N160. We performed near-infrared polarimetry to those star forming regions with IRSF/SIRPOL 1.4-m telescope. Near-infrared polarization enabled us to trace the detailed structure of magnetic fields in star-forming regions. Through the polarimetric data of J, H, and Ks bands, we examined the magnetic field structures in the N159/N160 complex. In this presentation, we show complex distribution of the magnetic fields associated with dust and gas structures. We verify the local magnetic fields in each star-forming region, which appear to be related with local environments, such as interior and boundary of shell structure, star-forming HII regions, and boundaries between HII regions and dense dark clouds. We discuss the formation scenario of the N159/N160 complex suggested from the magnetic field structure.

• 한국대기환경학회지
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• 제26권4호
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• pp.380-391
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• 2010

Airborne in-situ measurements of aerosol/cloud number concentrations were analyzed to investigate the effects of aerosols on warm cloud formation in the Pacific Dust Experiment (PACDEX) during April and May 2007. In the air masses originating from the Asian continent, high concentrations of fine particles including black carbon (BC) were observed when compared to other regions. A strong correlation (r=0.88) between condensation nuclei (CN) having sizes ranging from 0.1 to 1.0 mm ($CN_{0.1-1.0}$) and cloud condensation nuclei (CCN) at 0.4% supersaturation ($CCN_{0.4%}$) suggests that most of the $CN_{0.1-1.0}$ can contribute to cloud formation. The possibility of a cloud droplet formation by BC particles was expected at the high water vapor mixing ratio (WVMR) and the abundance of water-soluble components at the low altitude less than 3 km.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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• pp.307-312
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• 1998

The paper first describes the atmospheric correction algorithm for the Ocean Color and Temperature Scanner (OCTS) visible band data used at Earth Observation Center (EOC) of National Space Development Agency of Japan (NASDA). It uses 10 candidate aerosol models including "Asian dust model" introduced in consideration of the unique feature of aerosols over the east Asian waters. Based on the observations at 670 and 865 nm bands where the reflectance of the water body can be discarded, the algorithm selects a pair of aerosol models that accounts best for the observed spectral reflectances to synthesize the aerosol reflectance in other bands. The paper also evaluates the performance of the algorithm by comparing the satellite estimates of water-leaving radiance and chlorophyll-a concentration with selected buoy-and ship-measured data. In comparison with the old CZCS-type atmospheric correction algorithm where the aerosol reflectance is as-sumed to be spectrally independent, the OCTS algorithm records factor 2-3 less error in estimating the normalized water-leaving radiances. In terms of chlorophyll-a concentration estimation, however, the accuracy stays vey similar compared to that of the CZCS-type algorithm. This is considered to be due to the nature of in-water algorithm which relies on spectral ratio of water-leaving radiances.

• 드라이브 ㆍ 컨트롤
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• 제10권2호
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• pp.23-29
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• 2013

The excavator is used in a variety of construction environments. There are many kinds of risk like falling rocks or harmful dust. The excavator cabin protects the operator not only from these harmful environments but also provides a comfortable working environment. By the way, the excavator cabin consumes a lot of energy for cabin air conditioner. For this reason, the research is required to reduce energy consumption. This study suggests the air conditioning system for excavator using forced exhaust. First, the forced exhaust system simulated by AMESim tool and surveyed the applicability. Using AMESim simulation, it was investigated the effect of cabin inside temperature by intake flow rate and intake air temperature. The experiment executed using the 1.5 ton excavator and field tested according to the intake flow rate. Finally, verified the applicability on the air conditioning system for excavator using forced exhaust.

• 대한치과의사협회지
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• 제15권2호
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• pp.115-120
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• 1977

Extensive avulsion of the scalp, or stripping of a large area of soft tissue from the skull, is a serious accidnet. The avulsed scalp is often injured otherwise, such as by crushing, tearing, or from multiple laceration. The surrounding skin may be devitalized. Replacement of the scalp is usually followed by necrosis and sloughing within a short time. In such instances, the outer table of the cranium may become sucessively exposed. dry, dead, and affected by osteomyelitis. Hence the securing of early healing to prevent these is of the utmost importance. The successful case of reimplantation of the completely avulsed scalp, which is exposured to air for about 14 hours, is reported, in which there was partial growth of hair afterwards. The avulsed scalp caused by her long hair being caught in a grain belt was contaminated with hairs & dust. Authors treated this 19-year old female patient by split thickness skin graft, intermediate skin graft, full thickness skin graft from her own avulsed scalp.

• 대한원격탐사학회지
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• 제14권3호
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• pp.262-276
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• 1998

The paper first describes the atmospheric correction algorithm for the Ocean Color and Temperature Scanner (OCTS) visible band data used at Earth Observation Center (EOC) of National Space Development Agenrr of japan (NASDA). It uses 10 candidate aerosol models including "Asian dust model" introduced in consideration of the unique feature of aerosols over the east Asian waters. Based on the observations at 670 and 865 nm bands where the reflectance of the water body can be discarded, the algorithm selects a pair of aerosol models that accounts best for the observed spectral reflectances to synthesize the aerosol reflectance in other bands. The paper also evaluates the performance of the algorithm by comparing the satellite estimates of water-leaving radiance and chlorophyll-a concentration with selected buoy- and ship-measured data. In comparison with the old CZCS-type atmospheric correction algorithm where the aerosol reflectance is assumed to be spectrally independent, the OCTS algorithm records factor 2-3 less error in estimating the normalized water-leaving radiances. In terms of chlorophyll-a concentration estimation, however, the accuracy stays very similar compared to that of the CZCS-type algorithm. This is considered to be due to the nature of in-water algorithm which relies on spectral ratio of water-leaving radiances.

• 한국지형학회지
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• 제23권3호
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• pp.93-104
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• 2016

High school textbooks of world geography show geomorphic featuresin arid environments such as sand dune, yardang and ventifact which are largely created by aeolian processes. Desert pavements, ubiquitous armored surfaces composed of a mosaic of clasts in hot and arid regions, are introduced as a major landform which can be attributed to wind erosion. However, they are formed by a variety of processes including deflation, surface runoff, upward clast migration and dust accretion that cause coarse particles concentration at the surface. The deflation by wind leaving a lag of coarse clasts has been solely regarded at home, even though the classical mechanism of deflation has been evaluated as a relatively unimportant process of pavement formation abroad through empiricalstudies. The accretionary model is gaining wider acceptance, thus implying that desert pavements could be formed through deposition of aeolian material. In addition, sheetflood and upward migration of clasts, irrelevant to the aeolian processes, could also create stone pavements. As a consequence, the deflation process in high school textbooks has to be urgently modified into a range of processes including aeolian mantling. By stressing that desert pavements are an exceptional geomorphic feature in deserts where wind is a predominant geomorphic agent, they can be used as a good example to demonstrate that a landform is not monogenetic.

• Journal of Applied Biological Chemistry
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• 제64권1호
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• pp.1-4
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• 2021

Ambient air pollution, in particular, particulate matter (PM) pollution imposes serious health concerns such as hospitalization and premature deaths, worldwide. While commercial breathing masks are in use for protection against this hazardous issue, yet their efficiency in filtering PM was not up to the par, besides several other discomforts such as poor breathability due to reduced air flow, sweat production etc. In this study, commercial face mask coated with β-glucan, a high molecular weight polymer is tested for its efficacy in filtering PM. Quantification of PM before and after filtration and microscopic observation (using scanning electron microscopy (SEM)) of the fabric used in filtering the dust pollutants (generated from wood chips and cigarette) showed that β-glucan coated fabric were significantly efficient in capturing PM (size of 10 and 2.5 ㎛ in diameter) than that of the untreated control fabric, wherein the former had filtration efficacy with fold increase of 11.6 and 2.6 towards capturing PM2.5 and PM10 respectively than the latter. Thus, β-glucan coated fabric was found to be effective in filtering PM.