• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.99-109
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• 1992

Pathological studies by light and electron microscope were carried out on the twenty piglets naturally affected by encephalomyocarditis virus infection. Gross findings included pale or yellow, small necrotic foci on myocardium, together with pulmonary edema and liver congestion in some cases. On light microscopy, nonsuppurative interstitial endocarcitis, epicarditis and myocarditis, myocardial infarction, and dystrophic calcification or fibtosis were observed in heart. Perivascular cuffings, gliosis and nonsuppurative meningitis were appeared in brain. Focal or diffuse necrosis with mononuclear cell infiltration in lacrimal gland and multifocal necrosis in liver were observed in some cases. Congestion and edema of lung, hyperemia, hemorrhage and deletion of lymphocytes of lymph nodes and spleen were recognized. On electron microscopy, severe swelling and vacuolization of mitochondria and sarcoplasmic reticulum, large intracellular vacuolation and edema, separation and fragmentation of myofibrils were observed. Virus particles were seen in the sarcoplasm of degenerated cardiac muscle cell.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.5
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• pp.683-689
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• 2012

Photovoltaic(PV) system is one of power generation systems. Solar light in PV system is like the fuel of the car. The quantity of electricity generation, therefore, is fully dependent on the available quantity of solar light on the system of each site. If a utility can predict the solar power generation on a planned site, it may be possible to set up an appropriate PV system there. It may be also possible to objectively evaluate the performances of existing solar systems. Based on the theories of astronomy and meteorology, in this paper, Perez model is simulated to estimate the available quantity of solar lights on the prevailed photovoltaic systems. Consequently the conditions for optimal power generation of each PV system can be analyzed. And the maximum quantity of power generation of each system can be also estimated by applying assumed efficiency of PV system. Perez model is simulated in this paper, and the result is compared with the data of the same model of Meteonorm. Simulated site is Daejeon, Korea with typical meteorological year(TMY) data of 1991~2010.

• Journal of the Korean Solar Energy Society
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• v.39 no.4
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• pp.55-67
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• 2019

Recently, as the amount of particulate matter blowing from China increases, the domestic air environment is rapidly deteriorating. This pollution of the atmosphere greatly affects the light energy reaching the ground. Particularly, since the light enters the solar cell module in various forms, the amount of input energy of the solar power generation system may be changed depending on the ratio of direct beam irradiation and diffused horizontal irradiation. In this paper, we analyze how the ratio of direct beam component and diffused component on global horizontal irradiation varies with the atmospheric conditions. In addition, the reliability of the regression equation, designed to decompose the global horizontal irradiation into horizontal direct beam irradiation and diffused horizontal irradiation, was verified according to the level of air pollution. So, we derive the most suitable decomposition model for use in domestic climatic conditions in Korea by comparing the ratio of direct and diffuse component on the horizontal which is calculated with Perez model and Watanabe model using the meteorological weather data observed for 14 months. Finally, to reduce the error of the transposition result, we verified the reliability of the decomposition which depends on the atmospheric environment.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.33.3-34
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• 2018

Galaxy clusters contain a diffuse component of stars outside galaxies, that is observed as intracluster light (ICL). Since the ICL abundance increases during various dynamical exchanges of galaxies, the amount of ICL can act as a measurement tool for the dynamical stage of galaxy clusters. There are two prominent ICL formation scenarios; one is related to the brightest cluster galaxy (BCG) major mergers, and the other to the tidal stripping of galaxies. However, it is still under debate as to which is the main ICL formation mechanism. In this study we improve on earlier observational constraints of the ICL origin, by investigating it in a massive fossil cluster at z~0.47. Fossil clusters are believed to be dynamically matured galaxy clusters which have dominant BCGs. Recent simulation studies imply that, BCGs have assembled 85~90% of their mass by z~0.4 (e.g., Contini et al. 2014). Thus our target is an optimal test bed to examine the BCG-related scenario. Our deep images and Multi-Object Spectroscopic observations of the target fossil cluster (Gemini North 2018A) allow us to extract the ICL distribution, ICL color map and ICL fraction to cluster light. We will present a possible constraint of the ICL origin and discuss its connection to the BCG and the host galaxy cluster.

• Publications of The Korean Astronomical Society
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• v.23 no.2
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• pp.31-35
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• 2008

We present analytical approximations for calculating the scattering and escape of non-ionizing photons from a plane-parallel medium with uniformly illuminated by external sources. We compare the results with the case of a spherical dust cloud. It is found that more scattering and absorption occur in the plane-parallel geometry than in the spherical geometry when the optical depth perpendicular to the plane and the radial optical depth of the sphere are the same. The results can provide an approximate way to estimate radiative transfer in a variety interstellar conditions and can be applied to the dust-scattered diffuse Galactic light.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.1
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• pp.219-224
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• 2014

In this paper, we study the scattering characteristics of particle using Mie scattering based on various variables such as particle size and refraction of particle, wavelength of laser and angle of receiver to get diffuse light. And we consist a optical system for particle detection, then analyzed the characteristics of the optical system. And based on these characteristics, we develop a particle detection chamber for particle counter and shows experiment result.

• Journal of Periodontal and Implant Science
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• v.30 no.3
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• pp.631-639
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• 2000

Desquamative gingivitis is characterized by a diffuse erythema of the free and attached gingiva associated with areas of vesiculation, erosion, and desquamation. Desquamative gingivitis is not a distinct disease entity but represents a reaction pattern of the gingiva to various stimuli. Pemphigus vulgaris, cicatricial pemphigoid, and lichen planus may presents as desquamative gingivitis. We observed 3 patients whose disease was limited to the gingiva, and studied them by light and direct immunofluorescence microscope. We classified them according to clinical, histologic, and immunopathologic observations. Identification of the underlying causes of desquamative gingivitis is of utmost importance and is dependent upon clinical, histologic, and immunologic criteria.

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.229-235
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• 1994

The hemal nodes of the Korean native cattle were studied by gross anatomy and light microscopy. Hemal nodes were spherical or ovoid in shape, and red or black in colors. A hemal node consisted of a thick capsule and a hilum, and had extensive subcapsular and deep sinuses distended by a great number of erythrocytes. Although a few lymphatic nodules and tissues were seen in the parenchyma, no typical cortex and medulla was defined. Blood vessels occurred, but lymph vessel was not observed in nodes. The stroma of the hemal node was composed of reticular cells and fibers. The parenchyma consisted of many erythrocytes and lymphocytes, and a few macrophages and megakaryocytes. The capsule and trabecula was a collagenous connective tissue with smooth muscle cells. B-lymphocytes were principally located in the lymphatic nodules of the hemal node. T-lymphocytes were scattered in the diffuse lymphatic tissues of the hemal node.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.258-259
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• 2014

이산화티타늄($TiO_2$)의 띠 간격 (Band-Gap) 에너지를, 자외선 영역에서 질소와 $Ag-PbMoO_4$를 이용하여 가시광 응답형 광촉매를 제조하기 위하여 실험하였다. 이와 함께 제조한 "$AgPbMoO_4+N-TiO_2$"가 $TiO_2$, $N-TiO_2$, $PbMoO_4$, $AgPbMoO_4$에 비해 에너지 흡수 파장대의 향상을 확인하고 XRD, XPS, FE-SEM, UV-vis-DRS diffuse reflectance spectroscopy 분석을 통해 특성평가 및 분말의 광촉매 활성을 염료의 광촉매 분해반응으로 규명하였다.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.71.1-71.1
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• 2011

Significant discrepancies have been found between the dust masses of edge-on spiral galaxies derived from various tracers (optical/near-infrared, far-infrared/sub-millimeter observations, and the variation of dust attenuation with viewing angle). Here we report the first detection of a vertically extended far-ultraviolet (FUV) and near-UV (NUV) emission in an edge-on spiral galaxy NGC 891. The vertically extended emission is interpreted as the dust-scattered light due to a extraplanar dust layer in NGC 891 that contains about the same mass as the standard thin dust disk. This new dust component completely encloses the stellar disk and bulge, and solves the puzzle of dust mass.