• Title/Summary/Keyword: Scattered Light

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Atmospheric correction by Spectral Shape Matching Method (SSMM): Accounting for horizontal inhomogeneity of the atmosphere

  • Shanmugam Palanisamy;Ahn Yu-Hwan
    • Proceedings of the KSRS Conference
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    • 2006.03a
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    • pp.341-343
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    • 2006
  • The current spectral shape matching method (SSMM), developed by Ahn and Shanmugam (2004), relies on the assumption that the path radiance resulting from scattered photons due to air molecules and aerosols and possibly direct-reflected light from the air-sea interface is spatially homogeneous over the sub-scene of interest, enabling the retrieval of water-leaving radiances ($L_w$) from the satellite ocean color image data. This assumption remains valid for the clear atmospheric conditions, but when the distribution of aerosol loadings varies dramatically the above postulation of spatial homogeneity will be violated. In this study, we present the second version of SSMM which will take into account the horizontal variations of aerosol loading in the correction of atmospheric effects in SeaWiFS ocean color image data. The new version includes models for the correction of the effects of aerosols and Raleigh particles and a method fur computation of diffuse transmittance ($t_{os}$) as similar to SeaWiFS. We tested this method over the different optical environments and compared its effectiveness with the results of standard atmospheric correction (SAC) algorithm (Gordon and Wang, 1994) and those from in-situ observations. Findings revealed that the SAC algorithm appeared to distort the spectral shape of water-leaving radiance spectra in suspended sediments (SS) and algal bloom dominated-areas and frequently yielded underestimated or often negative values in the lower green and blue part of the electromagnetic spectrum. Retrieval of water-leaving radiances in coastal waters with very high sediments, for instance = > 8g $m^{-3}$, was not possible with the SAC algorithm. As the current SAC algorithm does not include models for the Asian aerosols, the water-leaving radiances over the aerosol-dominated areas could not be retrieved from the image and large errors often resulted from an inappropriate extrapolation of the estimated aerosol radiance from two IR bands to visible spectrum. In contrast to the above results, the new SSMM enabled accurate retrieval of water-leaving radiances in a various range of turbid waters with SS concentrations from 1 to 100 g $m^{-3}$ that closely matched with those from the in-situ observations. Regardless of the spectral band, the RMS error deviation was minimum of 0.003 and maximum of 0.46, in contrast with those of 0.26 and 0.81, respectively, for SAC algorithm. The new SSMM also remove all aerosol effects excluding areas for which the signal-to-noise ratio is much lower than the water signal.

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A study on the Policy Formation Process of Multi-Functions of Social Welfare Facilities (사회복지시설 다기능화 정책 형성과정에 관한 연구)

  • Kim, Jin Woo
    • Korean Journal of Social Welfare
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    • v.69 no.1
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    • pp.125-145
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    • 2017
  • The Purpose of this research is to draw implications of Multi-Functions of social welfare facilities on non-public social welfare delivery system especially in the rural area where there is not enough welfare infrastructure. The policy formation process of social welfare facilities was reviewed with 'Modified Policy Streams Framework" which combined Kingdon's Model with Mucciaroni's Model. Multi-Functions Policy of Social Welfare Facilities was led by the government with background of powerful President's initial stage of taking the power and finally legislated by amending Social Welfare Service Act in line with efficiency of non-public social welfare delivery system. However, the process did not represent the summation of needs originated from social work practice. The government just play the role of collecting some evidence underpinning the necessity of multi-functions of social welfare facilities and rearanging how to deploy the multi-functions policy. As the result the multi-functions policy is not activated and is not able to be the key criteria in expanding social welfare infrastructure. However, in spite of these limitation, the issue of multi-functions of social welfare facilities can cast the light on expanding infrastructure in the rural area where the gross size of area in larger in comparison to the district in the metropolitan city whereas residents are scattered because more number of social welfare facilities can not be the solution due to the limitation of finance and logic of efficiency.

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Ultrastructural Description on Oogenesis of the Melania Snail, Semisulcospira libertina libertina (Gastropoda: Pleuroceridae) (다슬기, Semisulcospira libertina libertina의 난자형성과정에 관한 미세구조적 기재)

  • Kim, Eun-Kyoung;Lee, Jung-Sick
    • The Korean Journal of Malacology
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    • v.25 no.2
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    • pp.145-151
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    • 2009
  • The ultrastructural changes in germ cells during oogenesis of the melania snail, Semisulcospira libertina libertina have been investigated by light and electron microscopy. The ovary is located on the surface of the hepatopancreas in the spiral posterior region. The ovary exhibited greenish color in the gonadal mature season. The ovary was composed of a number of oogenic follicles. Oogenesis was divided into five stages with histological features: (1) oogonia, (2) previtellogenic, (3) initial vitellogenic, (4) active vitellogenic, and (5) mature stages. Oogonia were oval in shape, $4-6\;{\mu}m$ in diameter, and had a large nucleus. Previtellogenic oocytes were about $20\;{\mu}m$ in diameter and the cytoplasm reacted with hematoxylin in H-E satin. Initial vitellogenic stage, oocytes were $60-80\;{\mu}m$ in diameter, and small yolk granules of low electron density are scattered in the cytoplasm. Oocytes in the initial vitellogenic stage were connected with ovarian follicle by egg stalk. Active vitellogenic oocyte were $100-120\;{\mu}m$ in diameter. Electron density, size and quantity of yolk granules that are distributed in the cytoplasm have increased from the previous stage. Result of TEM observations, the oocyte contains well-developed Golgi complex, endoplasmic reticula and tubular mitochondria in the cytoplasm. Cytoplasm of mature oocyte was filled with proteinaceous yolk globules of high electron density. In this stage, the length of microvilli in the egg envelope was approximately $1.1\;{\mu}m$.

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The Study on Phase Separation Development by Curing Reaction Rate for Unsaturated Polyester/Polyvinylacetate Semi-IPN (Unsaturated Polyester/Polyvinylacetate Semi-IPN의 경화반응속도에 따른 상분리현상 연구)

  • Chang, Won-Young;Kim, Moo-Sool;Kim, Jin-Hwan;Nam, Jae-Do
    • Polymer(Korea)
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    • v.25 no.1
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    • pp.78-89
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    • 2001
  • Morphological changes of unsaturated polyester/polyvinylacetate semi-IPN were studied while the phase separation and the cure reaction occurred in a competing fashion. The light scattering and thermal analysis techniques were used to investigate the phase separation rates and mechanical properties resultantly induced by molecular diffusion of thermoplastic polymer during the curing process of thermosetting polymer. The reaction activation energy was calculated by using Flynn-Wall method and the semi-IPN structure exhibited various phase-separation morphological characteristics. When PVAc composition was 10 wt%, the phase separation was not observed during the curing reaction, but the phase separation occurred in a similar fashion to nucleation and growth(NG) mechanism at room temperature. On the other hand, when PVAc composition was over 11.65 wt%, the phase separation was generated in the middle of the curing process. Consequently, the phase separation seemed to influence the curing reaction rate, which was also supported by the changing activation energy with conversion and PVAc composition. Finally, the total scattered intensity was measured at various temperature, and subsequently the diffusion rates of phase separation R(${\beta}m$) were evaluated.

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Fine Structure of Sperm in the Korea Squirrel, Tamias sibiricus (한국산 다람쥐(Tamias sibiricus) 정자의 미세구조)

  • Lee, Jung-Hun;Park, Ki-Ryong
    • Applied Microscopy
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    • v.41 no.2
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    • pp.99-107
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    • 2011
  • Light microscope, and scanning and transmission electron microscopy were used to investigate the fine structure of sperm of the Korea squirrel, Tamias sibiricus. The sperm head of T. sibiricus was paddle in shape. The total length of T. sibiricus sperm was 67.8 ${\mu}m$. The length of sperm head was 7.8 ${\mu}m$, and the tail (60.0 ${\mu}m$) was consisted of four major segments: the neck (1.0 ${\mu}m$), middle (8.0 ${\mu}m$), principal (48.5 ${\mu}m$) and end piece (2.5 ${\mu}m$), respectively. Especially, the length of the middle piece is short, and end piece was very shorter than those of other rodents. The post-nuclear cap was occupied about a fifth of nucleus. The equatorial segment is located between the post-nuclear cap segment and acrosomal cap on the nuclear surface. Nine segmented columns were surrounded by the mitochondria, and numbers of gyres of mitochondria were 26. One segmented column was consisted ten to twelve knobs, and each of segmented column in the neck region connected with the nine outer dense fiber in the middle piece. Numerous satellite-like fibers were scattered around the segmented columns. Nos. 1, 5 and 6 of the outer dense fibers in the middle piece were larger than the others. A fibrous sheath and longitudinal column of the principal piece were in evidence, but the fibrous sheath and longitudinal column was not seen at the end piece. In conclusion, the structural features of sperm head and tail may be useful information to patterns of sperm evolution and classification of species.

Studies on the Storage of Fat-Containing Foods (I) -Effect of Storage Factors on the Rancidity of Fried Instant Noodle- (유지함유식품(油脂含有食品)의 보존성(保存性)에 관(關)한 연구(硏究) (제1보) -보존조건(保存條件)이 인스턴트 Noodle의 산패도(酸敗度)에 미치는 영향(影響)-)

  • Chang, Hyun-Ki;Sung, Nak-Eung
    • Korean Journal of Food Science and Technology
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    • v.4 no.1
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    • pp.18-23
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    • 1972
  • Fried instant noodles, manufactured on laboratory scale, preserved in sunlight, room temperature, removed package, at $30{\pm}2^{\circ}C$ and corrugated fiber board box to investigate the oxidative stability of fried products under a few factors of storage for 150 days. And obtained results were as follow. 1) Peroxide value P.O.V. and Acid value A.V. of fried instant noodles were increased slightly during the storage in orange color polycello package in the corrugated fiber board box in the dark room as shown in Fig. 1 and 2. They had not rancid odor and showed P.O.V. 18.8 after 150 days. 2) Preserving in room temperature removed package or with polycello package exposed to sunlight, P.O.V. and A.V. increased rapidly up to 100, 5 and they had rancid odor within 30 days. 3) Peroxide value showed increasing tendency on the storage at $30{\pm}2^{\circ}C$ and scattered light and rancid odor appeared from 90 to 120 days. 4) As peroxide value and refractive index increased, iodine value were decreased as Fig. 3. 5) In these test, P.O.V. is correlated with the organoleptic evaluation of rancidity however, they were not coincided exactly.

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AN ELECTRON MICROSCOPIC STUDY OF THE PERIAPICAL GRANULOMA AND THE PERIAPICAL CYST (치근단육아종(齒根端肉芽腫)과 치근단양종(齒根端襄腫)의 전자현미경적(電子顯微鏡的) 연구(硏究))

  • Yo, In-Ho;Lim, Sung-Sam
    • Restorative Dentistry and Endodontics
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    • v.13 no.2
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    • pp.283-294
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    • 1988
  • The purpose of this study was to investigate the characteristic features of the cells and tissues of the chronic periapical lesions using light microscope and electron microscope. Fifteen dental periapical lesions were obtained from the patients undergoing periapical surgery. Each specimen was divided into two parts along the tooth axis. One part was routinely processed for histopathologic examinations. 12 periapical lesions were diagnosed as granuloma and 3 periapical specimens as periapical cyst. The other part was fixed in 2.5% glutaraldehyde in 0.1M sodium cacodylate buffer at pH 7.4 and 1% osmic acid in same buffer. They were embedded in Epon 812. The semithin sections were used for the orientation of the lesions and the ultrathin sections were stained conventionally and examined with AEI Corynth 500 electron microscope. The results were as follows. 1. PMN and macrophages, which were dominant cell type, were scattered in small or large numbers throughout the central destructive area of granuloma. In the granulomatous area, plasma cells and lymphoytes were found in significant number and a lot of new capillary formation were revealed. Clefts caused by cholesterol were often seen in the connective tissue. Occasionally foam cells became collected in groups and epithelial proliferation were present. 2. In both granuloma and cyst, some plasma cells contained narrow cisternae of granular endoplasmic reticulum of which was tightly packed with electron dense materials, and other cells exhibited dilated profiles of granular endoplasmic reticulum. 3. In the area where plasma cells and lymphocytes were collected in groups, lymphocytes with well developed nucleolus and profuse cytoplasm were found and differentiating plasma cells were also present. 4. In the epithelial strands of the granulomatous area, epithelial cells contained enlarged endoplasmic reticulum, tonofilaments and ribosoms. Toward the intercellular space epithelial cells protruded a few microvilli. In the intercellular space, exudate-like electron dense materials, most of which was attached to the plasma membrane, appeared. 5. Some foam cells filled with numerous lipid droplets and others had lipid droplets and crystal-like structures. 6. Cyst epithelium consisted of bright cells and dark cells. The former had bright cytoplasm and small amounts of ribosoms, and the latter dark cytoplasm, many ribosoms, mitochondria and elongated microvilli. 7. Epithelial cells near the cyst lumen protruded a lot of long microvilli toward intercellular space and cyst lumen.

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Optical Clearing Agent Decreases Scattering of Stratum Corneum and Modulates Physical Properties of Corneocytes by Hydration (광산란 감소 물질에 의한 피부 각질층의 산란 감소 및 수화에 의한 각질세포의 물리적 특성에 대한 연구)

  • Jun, Seung-Hyun;Yeom, Jun-Seok;Ahn, Byung Jun;Park, Sun Gyoo;Lee, Cheon Koo;Lee, Seol-Hoon;Kang, Nae-Gyu
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.44 no.1
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    • pp.81-87
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    • 2018
  • The objective of this article is to provide analytical tools for the scattering of stratum corneum (SC) and to check whether the optical clearing agents (OCAs) could be applied in optics affecting the scattering reduction. Dark field images of tape striped corneocyte separates scattered light of the SC from others in vitro. Several optical clearing agents were tested to reduce the scattering. Physical properties of SC such as water contents, keratin configuration and volume after OCAs treatment were investigated by FT-IR and 3D laser microscope. Several reducing sugars, monomeric sugars, sugar alcohol, and hyaluronic acid, which were used as humectants in cosmetic field, also reduced scattering. However, unlike dehydration in optics, water penetrated into the keratin in SC and scattering was decreased at low concentration of OCAs. In that condition, the volume of corneocyte was increased and stiffness seemed to decrease. The analyzing of tape-stripped SC, showed the change of optical and physical properties of corneocyte by optical clearing agents. The hydration of SC layer by optical clearing agents decreased the scattering of corneocyte and thus improved the skin appearance and moisturizing effect, which are important benefits in the cosmetic field and could provide new possibility to develop skin care study targeting at SC.

Remote Sensing of Atmospheric Trace Species using Multi Axis Differential Optical Absorption Spectroscopy (Multi Axis DOAS를 이용한 대기미량 물질 원격 측정)

  • Lee Chul-Kyu;Kim Young-Joon
    • Korean Journal of Remote Sensing
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    • v.22 no.2
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    • pp.141-151
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    • 2006
  • UV-visible absorption measurement techniques using several horizone viewing directions in addition to the traditional zenith-sky pointing have been recently developed in ground-based remote sensing of atmospheric constituents. The spatial distribution of various trace gases close to the instrument can be derived by combing several viewing directions. Multi-axis differential optical absorption spectroscopy (MAX-DOAS) technique, one of the remote sensing techniques for air quality measurements, uses the scattered sunlight as a light source and measures it at various elevation angles (corresponding to the viewing directions) by sequential scanning with a stepper motor. A MAX-DOAS system developed by GIST/ADEMRC has been applied to measuring trace gases in urban air and plumes of the volcano and fossil fuel power plant in January, May, and October 2004, respectively. MAX-DOAS spectra were analyzed to identify and quantify $SO_2,\;NO_2,\;BrO,\;and\;O_4$ (based on Slant Column Densities, SCD) in the urban air, volcanic plume, and fossil fuel power plant utilizing theirs specific structured absorption features in the UV-visible region. Vertical scan through the multiple elevation angles was performed at different directions perpendicular to the plume dispersion to retrieve cross-sectional distribution of $SO_2\;or\;NO_2$ in the plumes of the volcano and fossil fuel power plant. Based on the estimated cross sections of the plumes the mixing ratios were estimated to 580 $SO_2$ ppbv in the volcanic Plume, and 337 $NO_2\;and\;227\;SO_2$ ppbv in the plume of the fossil fuel power plant, respectively.

A study to Improve the Image Quality of Low-quality Public CCTV (저화질 공공 CCTV의 영상 화질 개선 방안 연구)

  • Young-Woo Kwon;Sung-hyun Baek;Bo-Soon Kim;Sung-Hoon Oh;Young-Jun Jeon;Seok-Chan Jeong
    • The Journal of Bigdata
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    • v.6 no.2
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    • pp.125-137
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    • 2021
  • The number of CCTV installed in Korea is over 1.3 million, increasing by more than 15% annually. However, due to the limited budget compared to the installation demand, the infrastructure is composed of 500,000 pixel low-quality CCTV, and there is a limits on identification of objects in the video. Public CCTV has high utility in various fields such as crime prevention, traffic information collection (control), facility management, and fire prevention. Especially, since installed in high height, it works as its role in solving diverse crime and is in increasing trend. However, the current public CCTV field is operated with potential problems such as inability to identify due to environmental factors such as fog, snow, and rain, and the low-quality of collected images due to the installation of low-quality CCTV. Therefore, in this study, in order to remove the typical low-quality elements of public CCTV, the method of attenuating scattered light in the image caused by dust, water droplets, fog, etc and algorithm application method which uses deep-learning algorithm to improve input video into videos over quality over 4K are suggested.