• Title/Summary/Keyword: Evans

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Discovery of a VeLLO in the "Starless" Dense Core L328

  • Lee, Chang-Won;Bourke, Tyler L.;Myers, Philip C.;Dunham, Mike;Evans, Neal;Lee, Young-Ung;Huard, Tracy;Wu, Jingwen;Gutermuth, Robert;Kim, Mi-Ryang;Kang, Hyun-Woo
    • The Bulletin of The Korean Astronomical Society
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    • v.34 no.1
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    • pp.92.2-92.2
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    • 2009
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New Records of Aphelinids, Encarsia Förster (Hymenoptera: Aphelinidae), in Korea (우리나라 Encarsia Förster에 대한 보고(벌목: 면충좀벌과))

  • Suh, Soo-Jung;Evans, Gregory A.
    • Korean journal of applied entomology
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    • v.54 no.3
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    • pp.281-284
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    • 2015
  • Two species of Encarsia, Encarsia explorata (Silvestri) from Aulacaspis rosarum Borchsenius, A. yabunikkei Kuwana and Lepidosaphes pinnaeformis ($Bouch\acute{e}$), and Encarsia lutea (Masi) from Bemisia tabaci (Gennadius) are newly documented in the Korean fauna of aphelinids (Hymenoptera: Aphelinidae). Brief diagnostic criteria, photographs, and information on the distribution and hosts of these species are provided. Also a key to species of Encarsia from Korea is given for correct species identification.

Immunoregulative Action of Bangpoongtongsungsan (방풍통성산(方風通聖散) 전탕액(煎湯液)의 면역(免疫) 조절작용(調節作用))

  • Lee, Chang-kyu;Song, Jeong-mo
    • Journal of Sasang Constitutional Medicine
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    • v.10 no.2
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    • pp.589-613
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    • 1998
  • The purpose of this research was to investigate effects of Bangpoongtongsungsan water extract(BTSE) on the immune reaction, anti-allergy action and anti-inflammatory action in BALB/c mice. The administration of BTSE (500mg/kg) enhanced the cell viability of thymocytes and the population of helper T cells in splenic T-lymphocytes. BTSE suppressed the production of nitric oxide, but enhanced the phagocytic activity in peritoneal macrophages. BTSE enhanced hemagglutination titer in mice. BTSE inhibited passive cutaneous anaphylaxis induced by egg albumin in rat, the lethal anaphylaxis induced by platelet activating factor and compound 48/80 in mice, and then inhibited the degranulation of peritoneal mast cells induced by compound 48/80. BTSE did not inhibit Arthus reaction, but inhibited the delayed type hypersensitivity induced by SRBC and contact dermatitis induced by DNFB. BTSE inhibited the acute hind paw edema induced by histamine after 30 minutes, the permeability of evans blue into peritoneal cavity induced by acetic acid and the writhing syndrome induced by acetic acid. These results suggest that BTSE has an immunopotentiative action, anti-allergy action and anti-inflammatory action via the inhibition of histamine release.

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A BVR Photometric Survey of the Small Magellanic Cloud with a Mosaic CCD

  • Lee, Ki-Won
    • Journal of the Korean earth science society
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    • v.34 no.5
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    • pp.415-427
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    • 2013
  • We performed a BVR photometric survey for the entire Small Magellanic Cloud (~26 deg 2 ) with a mosaic system, Wide Field Imager (WFI), covering three seasons: September and October 2001 and November 2002. Through the usual data reduction procedures, we present ~0.73 million catalogue stars brighter than 19 magnitude in B amongst a total of ~1.3 million and compare them with published astrometry and photometry results. We found that the average differences between our and the published data are ~0.7 arcsec in astrometry and 0.065, 0.054, and 0.163 in B, V, and R, respectively, in photometry. In addition, using the 2dF spectroscopic data from Evans et al. (2004), we determined the color excesses in (B-V) and (V-R) to be $0.086{\pm}0.156$, and $0.065{\pm}0.112$, respectively, while for the distance modulus, we obtained $18.55{\pm}1.05$.

Discovery of a VeLLO in the "Starless" Dense Core L328

  • Lee, Chang-Won;Bourke, Tyler L.;Myers, Philip C.;Dunham, Mike;Evans, Neal;Lee, Young-Ung;Huard, Tracy;Wu, Jin-Gwen;Gutermuth, Robert;Kim, Mi-Ryang;Kang, Hyun-Woo
    • Bulletin of the Korean Space Science Society
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    • 2009.04a
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    • pp.47.2-47.2
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    • 2009
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An Approach of Combining Failure Physics and Lifetime Analysis for Product Reliability Improvement: An Application to BGA(Ball Grid Array) Package (고장물리와 수명분석을 이용한 제품신뢰도 개선: BGA(Ball Grid Array) 패키지에 대한 사례연구를 중심으로)

  • Lee, K.T.;Shin, C.H.;Hahn, H.S.;Evans, J.W.;Kim, S.W.;Lee, H.J.
    • Journal of Korean Institute of Industrial Engineers
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    • v.25 no.2
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    • pp.204-216
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    • 1999
  • Failure physics and statistical lifetime analysis constitute the two extreme ends of the reliability engineering spectrum, and studies that relate failure mechanisms to failure distributions have been near non-existent. This paper is an attempt to stimulate interest to fill the gap between the two extremes and proposes an approach of combining them through i) developing a failure mechanism model, ii) generating failure times by Monte Carlo simulation with the model, iii) deriving the failure time distribution and evaluating the product reliability, and iv) improving the product reliability by the sensitivity analysis. An application of the proposed approach to the BGA(Ball Grid Array) surface mount package is also provided.

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Tightness of the Transition State for the Reactions of Secondary Alkyl Arenesulfonates with Anilines in Acetonitrile

  • 오혁근;권영봉;정동수;이익춘
    • Bulletin of the Korean Chemical Society
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    • v.16 no.9
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    • pp.827-831
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    • 1995
  • Kinetic studies on the reactions of five secondary acylic alkyl arenesulfonates with anilines are carried out in acetonitrile at 65.0 ℃. The magnitude of ρXZ determined (ρXZ=0.12-0.13) is slightly greater than that for the alicyclic series (ρXZ=0.11) under the same experimental condition. Ab initio MO results are found to support the slightly tighter transition state expected from the greater magnitude of ρXZ for the acyclic series. Despite the small variations, the magnitude of ρXZ and the theoretical transition state tightness remain relatively constant for the secondary carbon centers. Secondary kinetic isotope effects involving deuterated aniline nucleophiles show a successively smaller kH/kD(<1.0) value for a more sterically crowded reaction center carbon. This is in accord with the later transition state for bond-making predicted by the Bell-Evans-Polanyi principle for the more endothermic nucleophilic substitution reaction. Further support is provided by the results of the AM1 MO calculations on the reactions of secondary alkyl benzenesulfonates with chloride nucleophile.

Effects of Compound-A on the Early-Phase Anaphylactic Type Hypersensitivity

  • Lee, Ji-Yun;Lee, Jin-Hee;Kim, Tae-Doo;Sim, Sang-Soo;Kim, Chang-Jong
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.125.3-126
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    • 2003
  • Effect of Compound-A, a phenylpropanoid isolated from Arctium lappa fruit, on heterologous passive cutaneous anaphylaxis (HPCA), the release of histamine, and Phospholipase $A_2$ (PLA2) and phosphadiesterase (PDE) activities were studied by the method of Levine and Vaz. Anti-serum was prepared from ovalbumin (OA)-sensitized male Balb/c mouse at two weeks after the last challenge of OA and alumina gel. Heterologous PCA test in rats were carried out to determine the contents of leakaged pigment in the dorsal skin 30 minutes after i.v. injection of 0.2 ml of 1 % OA and 1 % Evans blue mixture (1:1). (omitted)

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Bottom Mass Transport Considering the Interaction of Waves with an Array of N Circular Cylinders (N개의 원형 실린더 주위에서의 해저면 토사이동)

  • Cho, I. H.;Hong, S. Y.
    • Journal of Korean Port Research
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    • v.9 no.1
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    • pp.57-63
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    • 1995
  • In this paper we examine the mass transport within the boundary layer near the sea bottom. The fluid domain is seperated into inner and outer region of boundary layers. In outer region, the wave field is assumed to be inviscid and irrotational. When the incident waves enter the arrays of circular cylinders, the scattering of water waves by an array of N bottom mounted vertical circular cylinders is solved using the method proposed by Linton & Evans under the potential theory. In inner region, the Navier-Stokes equation must be satisfied with boundary conditions at the boundary later and bottom is to be represented by the sum of the Eulerian mean drift and the Stokes' drift.

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PROJECT COMPLEXITY AS A MODERATOR OF PERFORMANCE BIAS TOWARDS OVERRUN

  • Li liu;Andrew Nguyen;James Arvanitakis
    • International conference on construction engineering and project management
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    • 2011.02a
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    • pp.38-45
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    • 2011
  • Studies have shown that infrastructure projects have continued to experience significant delays and cost overrun over an extended period of time and no evidence of learning ever have happened [1] [2]. Various causes contribute to the bias towards overrun [3]. This study contributes to literature by developing and subsequently validating a set of hypothesized relationships between project complexity and project performance. The results show that project complexity is associated with both the magnitude and variance of overrun. Further, the extent and magnitude of the positive bias towards overrun are moderated by project complexity.

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