• Title/Summary/Keyword: 소멸비

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Histopathological and Fine Structural Changes in Mouse Skin after Injection of Honeybee Venom (꿀벌의 독에 의한 생쥐 피부의 조직병리학적 및 미세구조적 변화)

  • Shin, Sang-Hee;Jeong, Moon-Jin;Moon, Myung-Jin
    • Applied Microscopy
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    • v.27 no.2
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    • pp.145-153
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    • 1997
  • Histopathological and fine structural changes in mouse skin after injection of venoms extracted from the venom glands of the honeybee, Apis mellifera, were studied with light and electron microscopes. At this experiment the venoms were directly injected at the hairless abdominal skin of the mouse through the sting of the bee's venomous organ. Main changes appeared within one hour after injection at both epithelial and connective tissues as considerable hyperemia and angioedema, and slight edema and fibrosis. High magnified electron micrographs reveal not only increase of diameter but also deposition of electron dense grains (which seems to be an auto immunoglobulin) at the collagenous fibers characteristically. This kinds of histological and fine structural responses were diminished from 12 hour after injection, and the pathological symptoms disappeared within 3 days at most cases. So, the skin responses induced by honeybee venom seem to be not severe compare to other cases reported by other venomous arthropods.

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Efficient Link Aggregation in Delay-Bandwidth Sensitive Networks (지연과 대역폭이 민감한 망에서의 효율적인 링크 집단화 방법)

  • Kwon, So-Ra;Jeon, Chang-Ho
    • Journal of Internet Computing and Services
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    • v.12 no.5
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    • pp.11-19
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    • 2011
  • In this paper, Service Boundary Line approximation method is proposed to improve the accuracy of aggregated link state information for source routing in transport networks that conduct hierarchical QoS routing. The proposed method is especially useful for aggregating links that have both delay and bandwidth as their QoS parameters. This method selects the main path weight in the network and transports the data to the external networks together with the aggregation information, reducing information distortion caused from the loss of some path weight during aggregation process. In this paper, the main path weight is defined as outlier. Service Boundary Line has 2k+5parameters. k is the number of outliers. The number of storage spaces of Service Boundary Line changes according to the number of outliers. Simulation results show that our approximation method requires a storage space that 1.5-2 times larger than those in other known techniques depending on outlier selection method, but its information accuracy of proposed method in the ratio between storage space and information accuracy is higher.

Revision of the Input Parameters for the Prediction Models of Smoke Detectors Based on the FDS (FDS 기반의 연기감지기 예측모델을 위한 입력인자 재검토)

  • Jang, Hyo-Yeon;Hwang, Cheol-Hong
    • Fire Science and Engineering
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    • v.31 no.2
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    • pp.44-51
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    • 2017
  • Accurate predictions of the activation time for smoke detectors using a fire simulation is are required to ensure the reliability of the RSET (Required Safe Egress Time) calculation in the process of PBD (Performance-Based Design). The objective of this study was to enhance the accuracy of input parameters for the numerical models of smoke detector based on the FDS. To this end, a Fire Detector Evaluator (FDE) developed in previous studies was improved. The uniformities of flow and smoke inside the FDE were improved and accurate measurements of the obscuration per meter (OPM) related to detector operation were also performed through a decrease in the forward scattering of smoke particles. The input parameters using the improved FDE showed a significant difference from the previous FDE quantitatively. In particular, a larger difference was found in a photoelectric detector compared to an ionization detector. Considering that the operating conditions of smoke detectors are affected by the detector type, combustibles, smoke particulars, and color, the database (DB) on the input parameters for various detectors and combustibles should be built to improve the reliability of PBD in future studies.

야외규모 TCE 질량전이 모델의 개발

  • Park Eun-Gyu;Parker John C.
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2005.04a
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    • pp.72-75
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    • 2005
  • 본 연구에서는 야외규모 TCE (trichloroethylene) 질량전이역학을 평가하기 위해 TCE의 대수층 내 유입 및 용해상 거동을 고해상도 수치 모사를 실시하였다. 공간적으로 불균질한 대수층 $10{\times}10{\times}10m$ 도메인 내부의 유입된 TCE 분포를 모사하기 위해 본 연구를 통해 개발된 정성적 침투모델(percolation model)이 이용되었다. 이를 기초로 하여 연계되어진 (coupled) 지하수 유동 및 용해상 거동 장기 (long-term) 모사를 실시하였다. 지엽적으로 일어나는 질량전이는 기존 연구를 통하여 발표되어진 실험실규모 연구에 기초하였다. 지하수가 도메인을 지나 흘러나가는 경계면에서 측정되어진 용해상 (aqueous phase) TCE의 질량선속 (mass flux)을 통해 실질 야외규모 질량전이 상수가 계산되었다. 관찰된 바 야외규모 질량전이 상수는 실험실 연구를 통해 측정된 값에 비하여 휠씬 작은 값을 보였으며 이는 지하수 유속 및 TCE의 불균질한 분포에 기인한다. 야외규모 질량전이 상수는 평균 지하수 유속에 직접 비례하는 것으로 관찰되었고 이는 기존 실험실 연구를 통해 알려진 평균 지하수 유속의 0.7승이라는 결과와 대조되는 것이다. 또한 모사를 통해 관찰된 야외규모 질량전이 상수는 상대 TCE 질량의 고갈상수 승에 비례함을 보였다. 이러한 고갈상수는 TCE가 측방으로 퍼지는 현상이 강한 대수층, 즉 저투수성 층의 발달이 양호한 대수층, 에서는 1보다 작은 값을 갖고 그렇지 않은 대수층, 즉 저투수성 층의 발달이 미약한 대수층, 에서는 대체적으로 1보다 높은 값을 갖는 것으로 관측되었다. 이는 DNAPL의 측방 퍼짐이 강한 대수층에서는 용해로 인한 시간에 따른 오염원 부근에서의 농도 감소가 미약하기 때문인 것이며, 그와 반대로 DNAPL의 측방 퍼짐이 약한 대수층에서는 시간이 지남에 따라 용해에 의해 지속적으로 오염원 부근에서의 농도가 감소 또는 소멸함으로 인하여 측정되는 용해상 DNAPL의 질량 선속 역시 계속적으로 감소되는 것으로 밝혀졌다.

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Improvement of detection sensitivity of impurities on Si wafer surface using synchrotron radiation (방사광을 이용한 Si 웨이퍼 표면불순물 검출감도 향상)

  • 김흥락;김광일;강성건;김동수;윤화식;류근걸;김영주
    • Journal of the Korean Vacuum Society
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    • v.8 no.1
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    • pp.13-19
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    • 1999
  • Total reflection X-ray fluorescence spectroscopy using synchrotron radiation source called as TRSFA was explored to achieve high sensitivities to impurity metals on Si wafer surface. It consists of monochromating part to select a specific wavelength, slit part to shield direct beam and to control monochromated beam, and main chamber to dectect fluorescent X-ray counts of impurities on si wafer. Monochromated X-ray of 10.90 KeV was selected and the optimum total reflection condition on silicon wafer was obtained through tuning the dead time and fluorescent X-ray count of Si and Fe. TRSFA system could increase the sensitivity as high as 50 times in comparision with TRXFA using normal X-ray source. But the trend was varied since the surface conditions of Si wafers and, therefore, the reflectivities were different. Furthemore, there seems to be a promising path to reaching a detection limit useful to the next generation metal impurities control, because Fe impurity below to the $5\times10^{9}\textrm{atomas/cm}^2$ can be detectable through the developed TRSFA system.

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Preservative Effect of Grapefruit Seed Extract on Fish Meat Product (어묵에 처리한 grapefruit 종자추출물의 보장효과)

  • 조성환;주인생;서일원;김재욱
    • Journal of Food Hygiene and Safety
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    • v.6 no.1
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    • pp.67-72
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    • 1991
  • This study was carried out to investigate the preservative effect of grapefruit seed extract on fish meat product. he effect of GFSE has been tried on fish meat product divided into three lots; Control (no treatment), 500 ppm and 1,000 ppm of GFSE-treated samples. The results were summarized as follows; 1 During the storage of fish meat product, chagnges of crude protein contents of GFSEtreated samples were smaller than the control. 2 Texture was inclined to decrease as the storage period goes, the decrease ratio of GFSEtreated samples was smaller than the control. 3. SDS-PAGE patterns of fish meat product treated with or without GFSE showed that Mw 30,000-32,000 of major proteins were hydrolyzed and disappeared. The deterioration of fish meat product proteins occured in the storage period of 2 days in the control and 4-5 days in GFSE-treated samples. Conclusivery, the excellent preservative effects of GFSE on fish meat product were shown in the rheological, chemical test and sensory evaluation.

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A Near Saturation Routing Algorithm for Non-hieratical Networks (비계층적 통신망에서의 근사 포화형 경로설정 알고리즘)

  • 길계태;은종관;박영철;이상철
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.11
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    • pp.1037-1053
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    • 1991
  • Flooding is known to be an effective routing mechanism not only in circuit switched networks but also packet switched networks since it minimizes the time required for up calls and does not have to maintain routing tables or distance tables by periodically intercommunicating among all the network nodes. However, one main drawback of it is the overhead on the control message signaling channels, In the paper, we propose an overlaying scheme on the existing mechanism that retains the desired properties of flooding, yet provides congestion control to the network. This is done by utilizing the wasted search messages to inform the network of the conditions of each path from one node to another. The overhead is to maintain a path table in each node. However, this overhead is not so critical. Also, this scheme can take advantages further by limiting the extent of message propagation through the network and by incorporating trunk reservation schemes additionally.

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Morphological Studies on Hemocytes of the Common Shore Crab, Helice tridens tridens (Decapoda, Crustacea) (방게(Helice tridens tridens) 혈구의 형태학적 연구)

  • 윤상선;노용태
    • The Korean Journal of Zoology
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    • v.38 no.3
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    • pp.330-339
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    • 1995
  • In Helice tridens tridens, hylaine cells, small granulocytes, and large granulocytes were identified. Features of hyaline cells include a large nucleus in proportion to the cytoiplasm, and weak electron-dense granules of oval shape and vesicles, and endoplasmic reticulum (ER) in the cytoplasm. Small granulocytes have smaller nucleus than that of the hyaline cells, well-developed ER, Golgi complex, and small, round and electron-dense granules in the cytoplasm. Large granulocytes contain large and electron dense granules (ahout 1 $\mu$m) that fused small granules. Hemocytes of Helice tridens tridens differentiated from hyaline cell to large granulocyte granules of hyaline cells have lysosome and make small vesicles from nuclear envelopes. While these vesicles pass through the Golgi complex, they are filled with electron dense matetials, and then fused with the small granules. They eventually matured into large granules. All of hemocytes have the glycogen particles. In the large granulocytes heterogeneouse granules were supposed to occur by disappearance of granules.

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Effects of Ozone on Photosynithetic Activity in Chloroplast of Barley (Hordeum vulgare L.) (오존이 보리(Hordeum vulgare L.) 엽록체의 광합성 활성에 미치는 영향)

  • 정화숙
    • Journal of Plant Biology
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    • v.38 no.4
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    • pp.399-407
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    • 1995
  • The effects of 0.5 and 1.0 ppm of ozone on the developing chloroplast of barley (Hordeum vulgare L) seedling during greening were investigated by PSI and II activities, chlorophyll fluorescence, and the contents of chlorophyll. Etiolated barley seedling was treated 0.5 and 1.0 ppm ozone for the first 4 h during greening. In 24 h greening experiment, the contents of chlorophyll were decreased by increasing ozone concentration from 0.5 ppm to 1.0 ppm. In 24 h greening experiment, Fo, Fv, Fm and qE were greatly decreased as the concentration of ozone was increased, but those were not considerably decreased in 48 h greening experiment. In another experiment, the developing barley seedling was treated with 0.5 and 1.0 ppm ozone for the last 4 h during greening period, which was 24 h or 48 h. In both experiments the PS II activity was decreased as the concentration of ozone was increased, but not in PS I activity. Fv, Fm and Fv/Fo were also decreased as the concentration of ozone was increased. qP and qR were strikingly decreased as the concentration of ozone was increased in both experiments.iments.

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Difference in Components of Epimedium koreanum in Compliance with Seasons and Places of Collection (삼지구엽초의 채취시기(採取時期) 및 산지별(産地別) 성분(成分) 차리(差異))

  • Shin, Kuk-Hyun;Lim, Soon-Sung;Ahn, Sang-Deuk;Kim, Sung-Kyeong;Park, Kyeong-Yeol
    • Korean Journal of Medicinal Crop Science
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    • v.4 no.4
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    • pp.321-328
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    • 1996
  • As a first step for improvement of breeding and productivity of Epimedii Herba, the patterns of components and the difference in icariin, a main component of this plant, in compliance with seasons and places of collection were evaluated by HPLC. As a result, the patterns of components in samples collected in July-September were shown to be markedly increased compared to those collected in May. Corresponding to the alternations of the pattern, the amount of icariin, which was estimated to be 0.017% in May was found to be increased markedly up to 0.82% in September. The samples collected at Chul-won district showed the highest icariin contents (0.94%), however, those collected in China was only 50% level (0.4%) of domestic ones. These results strongly suggest that the quality of Epimedii Herba might be quite different with respect to the seasons and places of the collection.

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