http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
압축성을 고려한 분율 흐름 접근 방식에 근거한 삼상흐름모델 개발
석희준,고경석,Suk, Hee-Jun,Ko, Kyung-Seok,Yeh, Gour-Tsyh 대한자원환경지질학회 2008 자원환경지질 Vol.41 No.6
대부분의 분을 흐름 접근 방식을 따르는 다상흐름모델들은 주로 유체나 매질의 비 압축성을 가정하거나 완전한 삼상 오염물을 다루지 않고 이상 유체 (물 또는 공기, 물 또는 불용융성유체)의 거동만을 다룬다. 그러나 본 연구에서는 유체 및 매질의 압축성과 완전한 삼상 오염물을 가정하는, 분율흐름접근방식을 따르는 수학적 지배방정식을 개발하고, 이를 토대로 압축성 유체 및 매질을 고려한 삼상흐름 수치모의프로그램을 개발하였다 개발된 삼상흐름 수치모의프로그램 (Compressible Multiphase Flow Simulator, CMPS)을 검증하기 위해서 기존에 개발된 비압축성 유체 및 매질을 고려한 삼상흐름수치모의 프로그램인 MPS (Suk and Yeh, 2007; Suk and Yeh, 2008) 및 해석해를 통해서 간접적으로 비교 검증하였다. 비교결과 CMPS와 MPS의 결과와 해석해들은 서로 잘 일치하였다. 따라서 CMPS는 압축성 유체 및 매질을 고려한 삼상흐름 수치모의를 구현 할 수 있는 가능성을 가진다. Most multiphase flow simulators following fractional flow approach assume incompressibility of fluid and matrix or consider only two phase flow (water and air, water and NAPL). However, in this study, mathematical governing equations were developed for fully compressible three-phase flow using fractional flow based approach. Also, fully compressible multiphase flow simulator (CMPS) considering compressibilities of matrix and fluid was developed using the mathematical governing equations. In order to verify CMPS, the CMPS were compared with analytical solution and the existing multiphase flow simulator, MPS, which had been developed for simulating incompressible multiphase flow (Suk and Yeh 2007; Suk and Yeh 2008). According to the results, solutions of CMPS and MPS and analytical solutions are well matched each other. Thus, it is found that CMPS has the capability of simulating compressible three phase flow phenomena assuming compressibilities of fluids and matrix.
Recent warming in the Yellow/East China Sea during winter and the associated atmospheric circulation
Yeh, S.W.,Kim, C.H. Pergamon Press ; Elsevier Science Ltd 2010 Continental shelf research Vol.30 No.13
We examine characteristics in the variability of sea surface temperature (SST) in the Yellow/East China Sea during the boreal winter (December-January-February) for the period 1950-2008 in observations. It is found that the mean SST in the Yellow Sea/East China Sea gradually increases during recent decades. A warming trend of a basin scale SST is significant in most of the regions in the Yellow/East Sea, which is well explained by the variability of the first empirical orthogonal function SST mode. We suggest one candidate mechanism that the North Pacific oscillation (NPO)-like sea level pressure play an important role to warm the Yellow/East China Sea. Anomalous anticyclonic circulation, which is the southern lobe of NPO-like sea level pressure over the North Pacific, causes a weakening of northerly mean winds over the Yellow/East China Sea during winter. This contributes to increase in the SST in the Yellow/East China Sea through the changes in the latent heat and sensible heat fluxes.
Yeh, J.Y.,Park, J.Y.,Ostlund, E.N. Elsevier Scientific Pub. Co 2011 Veterinary microbiology Vol.154 No.1
The rapid global expansion of West Nile virus (WNV) has recently raised concerns regarding its possible spread into South Korea. To date, WNV infection in wild birds in South Korea has not been identified. Bird migration is thought to be involved in spreading WNV, and wild birds are the possible routes of introduction of WNV infection. To assess the risk of WNV infection in South Korea, we conducted a nationwide WNV surveillance of wild birds, with an emphasis on migratory ducks from WNV-affected areas. Our chief aim was to determine whether birds with the potential to introduce WNV are present in South Korea by testing migrating and resident wild birds for WNV antibodies. We collected blood samples from 1531 wild birds representing 57 bird species at several major inland resting sites for migratory waterfowl in South Korea. A seroepidemiological analysis of WNV and Japanese encephalitis virus (JEV) infections was conducted using plaque-reduction neutralization tests (PRNTs) for each virus. To search for recent WNV infections, sera were also evaluated by IgM antibody capture ELISA. Of the 1531 serum samples, 5 (0.3%) tested positive for WNV-specific antibodies, and 70 (4.6%) tested positive for JEV-specific antibodies. A total of 9 (0.6%) samples were positive for both WNV and JEV antibodies; these samples were interpreted as having a flavivirus exposure. All birds that had neutralizing antibodies specific to WNV were negative for IgM, which indicates the likelihood of a relatively old infection. Along with the recognized distribution of flaviviruses along several duck species' migratory routes, our findings strongly suggest that some of the birds captured in this study had been exposed to WNV or JEV.
Yeh, Byung-Il,Choi, Jong-Whan,Sohn, Joon-Hyung,Lee, Hyean-Woo,Han, Dong-Pyou,Jung, Seun-Ho,Kim, Hyun-Won Korean Society for Biochemistry and Molecular Biol 1998 Journal of biochemistry and molecular biology Vol.31 No.6
X-ray crystallographic studies of the deoxy form of human adult hemoglobin (Hb A) have shown that ${\beta}99Asp$ is hydrogen bonded to both ${\alpha}42Tyr$ and ${\alpha}97Asn$ in the ${\alpha}_1{\beta}_2$ subunit interface, suggesting that the essential role of ${\beta}99Asp$ is to stabilize the deoxy-Hb by creating the intersubunit hydrogen bond. In particular, for Hb Kempsey (${\beta}99Asp{\rightarrow}Asn$), molecular dynamics simulation indicated that a new hydrogen bond involving ${\beta}99Asn$ can be induced by replacing ${\alpha}42Tyr$ with a strong hydrogen-bond acceptor such as Asp. Designed mutant recombinant (r) Hb (${\beta}99Asp{\rightarrow}Asn$, ${\alpha}42Tyr{\rightarrow}Asp$) have been produced in the Escherichia coli expression system and have shown that functional defects of Hb Kempsey could be compensated by the ${\alpha}42Tyr{\rightarrow}Asp$ substitution. However, as the ${\alpha}42 Tyr{\rightarrow}Asp$ mutation has never been reported before, it is still possible that the functional properties of r Hb (${\beta}99Asp{\rightarrow}Asn$, ${\alpha}42Tyr{\rightarrow}Asp$) may be due to the mutation itself. Thus, it is required to produce r Hb (${\alpha}42Tyr{\rightarrow}Asp$) and r Hb Kempsey (${\beta}99Asp{\rightarrow}AsnX$( as controls, and to compare their properties with those of r Hb (${\beta}99Asp{\rightarrow}Asn$, ${\alpha}42Tyr{\rightarrow}Asp$). r Hb (${\alpha}42Tyr{\rightarrow}Asp$) could not be purified because it is an unstable hemoglobin which forms Heinz bodies. r Hb Kempsey (${\beta}99Asp{\rightarrow}Asn$) exhibits very high oxygen affinity and greatly reduced cooperativity. Thus, r Hb (${\beta}99Asp{\rightarrow}Asn$) and r Hb (${\alpha}42Tyr{\rightarrow}Asp)$ compensate each other.
Confinement efficiency and size effect of FRP confined circular concrete columns
Yeh, Fang-Yao,Chang, Kuo-Chun Techno-Press 2007 Structural Engineering and Mechanics, An Int'l Jou Vol.26 No.2
The objective of this paper is to develop a finite element procedure for predicting the compressive strength and ultimate axial strain of Carbon Fiber Reinforced Plastics (CFRP) confined circular concrete columns and to study the effective parameters of confinement efficiency for helping design of CFRP retrofit technology. The behavior of concrete confined with CFRP is studied using the nonlinear finite element method. In this paper, effects of column size, CFRP volumetric ratio and plain concrete strength are studied. The confined concrete nonlinear constitutive relation, concrete failure criterion and stiffness reduction methodology after concrete cracking or crushing are adopted. First, the finite element model is verified by comparing the numerical solutions of confined concrete with experimental results. Then the effects of column size, CFRP volumetric ratio and plain concrete strength on the peak strength and ductility of the confined concrete are considered. The results of parametric study indicate that the normalized column axial strength increases with increasing CFRP volumetric ratio, but without size effect for columns with the same CFRP volumetric ratio. As the same, the increase in column ductility depends on CFRP volumetric ratio but without size effect for columns with the same CFRP volumetric ratio.