http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Shear Behavior and Performance of Deep Beams Made with Self-Compacting Concrete
Y. W. Choi,H. K. Lee,S. B. Chu,S. H. Cheong,W. Y. Jung 한국콘크리트학회 2012 International Journal of Concrete Structures and M Vol.6 No.2
An experimental study was carried out to evaluate fresh properties of a moderately high-strength (high-flowing) self-compacting concrete (SCC) and to investigate shear behavior and performance of deep beams made with SCC. Fresh and hardened properties of normal concrete (NC) and SCC were evaluated. The workability and compacting ability were observed based on casting time and number of surface cavities, respectively. Four-point loading tests on four deep beams (two made with SCC and two with NC) were then conducted to investigate their shear behavior and performance. Shear behavior and performance of beams having two different web reinforcements in shear were systematically investigated in terms of crack pattern, failure mode, and load?deflection response. It was found from the tests that the SCC specimen having a normal shear reinforcement condition exhibited a slightly higher load carrying capacity than the corresponding NC specimen, while the SCC specimen having congested shear reinforcement condition showed a similar load carrying capacity to the corresponding NC specimen. In addition, a comparative study between the present experimental results and theoretical results in accordance with ACI 318 (Building Code Requirements for Reinforced Concrete (ACI 318-89) and Commentary-ACI 318R-89, 1999), Hsu?Mau’s explicit method (Hsu, Cem Concr Compos 20:419?435, 1998; Mau and Hsu, Struct J Am Concr Inst 86:516?523, 1989) and strut-and-tie model suggested by Uribe and Alcocer (2002) based on ACI 318 Appendix A (2008) was carried out to assess the applicability of the aforementioned methods to predict the shear strength of SCC specimens.
Effect of growth interruption on InN / GaN single quantum well structures
S.-Y. Kwon,H. J. Kim,H. Na,H.-C. Seo,H. J. Kim,Y. Shin,Y.-W. Kim,S. Yoon,H.-J. Oh,C. Sone,Y. Park,Y. P. Sun,Y.-H. Cho,H. M. Cheong,E. Yoon 한국진공학회(ASCT) 2003 Applied Science and Convergence Technology Vol.12 No.S1
We successfully grew InN/GaN single quantum well structures by metal-organic chemical vapor deposition and confirmed their formation by optical and structural measurements. We speculate that relatively high growth temperature (730℃) of InN layer enhanced the formation of 2-dimensional quantum well structures, presumably due to high adatom mobility. As the growth interruption time increased, the PL emission efficiency from InN layer improved with peak position blue-shifted and the dislocation density decreased by one order of magnitude. The high resolution cross-sectional TEM images clearly showed that the InN layer thickness reduced from 2.5 ㎚ (without GI) to about 1 ㎚ (with 10 sec GI) and the InN/GaN interface became very flat with 10 sec GI. We suggest that decomposition and mass transport processes on InN during GI is responsible for these phenomena.
MG Prabagar,Y Do,S Ryu,J-Y Park,H-J Choi,W-S Choi,TJ Yun,J Moon,I-S Choi,K Ko,K Ko,C Young Shin,C Cheong,Y-S Kang 한국당과학회 2013 한국당과학회 학술대회 Vol.2013 No.1
Complements, such as C1q and C3, and macrophages in the splenic marginal zone (MZMs) play pivotal roles in the efficient uptake and processing of circulating apoptotic cells. SIGN-R1, a C-type lectin that is highly expressed in a subpopulation of MZMs, regulates the complement fixation pathway by interacting with C1q, to fight blood-borne Streptococcus pneumoniae. Therefore, we examined whether the SIGN-R1-mediated classical complement pathway plays a role in apoptotic cell clearance and immune tolerance. SIGN-R1 first-bound apoptotic cells and this binding was significantly enhanced in the presence of C1q. SIGN-R1-C1q complex then immediately mediated C3 deposition on circulating apoptotic cells in the MZ, leading to the efficient clearance of them. SIGN-R1-mediated C3 deposition was completely abolished in the spleen of SIGN-R1 knockout (KO) mice. Given that SIGN-R1 is not expressed in the liver, we were struck by the finding that C3-deposited apoptotic cells were still found in the liver of wild-type mice, and dramatically reduced in the SIGN-R1 KO liver. In particular, SIGN-R1 deficiency caused delayed clearance of apoptotic cells and aberrant secretion of cytokines, such as TNF-α, IL-6, and TGF-β in the spleen as well as in the liver. In addition, anti-double- and single-stranded DNA antibody level was significantly increased in SIGN-R1-depleted mice compared with control mice. These findings suggest a novel mechanism of apoptotic cell clearance which is initiated by SIGN-R1 in the MZ and identify an integrated role of SIGN-R1 in the systemic clearance of apoptotic cells, linking the recognition of apoptotic cells, the opsonization of complements, and the induction of immune tolerance.
Park, E.W.,Kim, J.H.,Lim, H.T.,Seo, B.Y.,Cho, I.C.,Lee, J.G.,Oh, S.J.,Cheong, I.C.,Lee, J.H.,Jeon, J.T. S. Karger AG 2004 CYTOGENETIC AND GEN0ME RESEARCH Vol.108 No.4
<P> </P><P>Copyright © 2005 S. Karger AG, Basel</P>
문우식(W.S.Moon),류준욱(J.W.Ryoo),조연근(Y.G.Cho),정홍석(H.S.Chung),정범서(B.S.Cheong) 한국자동차공학회 1998 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1998 No.5_1
Automotive fuel consumptions with different engine oils are determined according to the EPA FTP-75 method in this study. The results of fuel economy are discussed correlating with the properties of engine oils. To improve automotive fuel economy with engine oils, it is necessary to use VHVI base oils in formulating engine oil. The engine oils formulated with a VHVI base oil has better viscometric properties, resulting in better fuel economy. The temporary viscosity loss at 150℃ also affects automotive fuel economy.<br/>