http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Mathematical models applied to dispersal of pest populations in greenhouse
T. V. Nguyen,C.Xia,B.K.Chung,H.Y.Kim,T.S.Chona 한국응용곤충학회 2010 한국응용곤충학회 학술대회논문집 Vol.2010 No.05
A genome project has been launched and aims to sequence total genome of Cotesia plutellae bracovirus. On this process, several open reading frames (ORFs) have been identified. This study was intended to clone and express protein tyrosine phosphatase genes, PTP1 and PTP6. The ORFs of these two genes consist of 900 and 891 bp, respectively. PTP1 and PTP6 are genes of a group of genes that has been implicated as important regulatory components in cell growth, differentiation and malignant transformation by certain viruses. In this work,we studied the cloning and expression patterns of these genes in Plutella xylostella, a lepidopteran host of C. plutellae. A polymerase chain reaction (PCR) produced the corresponding products of PTP1/6. These PCR products were cloned and expressed using an expression vector pBAD-TOPO, and then over-expressed using an inducer, L-arabinose. Then the purified proteins were confirmed using Western blotting (immunoblotting using V5 antibody) and the apparent molecular weights of both proteins were about 40 kDa. Expression of PTP genes were analyzed in the parasitized P. xylostella by realtime RT-PCR, which indicated late expression pattern of both PTPs during parasitization. We are pursuing to elucidate their physiological function in the parasitized host insect.
Dai, Yunqian,Lim, Byungkwon,Yang, Yong,Cobley, Claire M.,Li, Weiyang,Cho, Eun Chul,Grayson, Benjamin,Fanson, Paul T.,Campbell, Charles T.,Sun, Yueming,Xia, Younan WILEY‐VCH Verlag 2010 Angewandte Chemie Vol.122 No.44
<P><B>Stützt ohne zu stören</B>: Das Aufbringen einer porösen SiO<SUB>2</SUB>‐Schicht auf Pt‐modifizierte TiO<SUB>2</SUB>‐Nanofasern ergibt einen sinterbeständigen Katalysator (siehe Bild). Die Pt‐Nanopartikel sinterten bei Temperaturen bis 750 °C an Luft nicht, weil die SiO<SUB>2</SUB>‐Schicht die Oberflächenwanderung physikalisch behindert; wegen der Porosität der Beschichtung behielt das System seine katalytische Aktivität aber bei.</P>
Xia-chun Chen,Zhi-zhou Bai,Yu Zeng,Rui-juan Jiang,Francis T.K. Au 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.21 No.5
Concrete bridges with corrugated steel webs and prestressed by both internal and external tendons have emerged as one of the promising bridge forms. In view of the different behaviour of components and the large shear deformation of webs with negligible flexural stiffness, the assumption that plane sections remain plane may no longer be valid, and therefore the classical Euler-Bernoulli and Timoshenko beam models may not be applicable. In the design of this type of bridges, both the ultimate load and ductility should be examined, which requires the estimation of full-range behaviour. An analytical sandwich beam model and its corresponding beam finite element model for geometric and material nonlinear analysis are developed for this type of bridges considering the diaphragm effects. Different rotations are assigned to the flanges and corrugated steel webs to describe the displacements. The model accounts for the interaction between the axial and flexural deformations of the beam, and uses the actual stress-strain curves of materials considering their stress path-dependence. With a nonlinear kinematical theory, complete description of the nonlinear interaction between the external tendons and the beam is obtained. The numerical model proposed is verified by experiments.
Plant leaf detection using modified active shape models
Xia, C.,Lee, J.M.,Li, Y.,Song, Y.H.,Chung, B.K.,Chon, T.S. Academic Press 2013 BIOSYSTEMS ENGINEERING Vol.116 No.1
We propose an in situ detection method of multiple leaves with overlapping and occlusion in greenhouse conditions. Initially a multilayer perceptron (MLP) is used to classify partial boundary images of pepper leaves. After the partial leaf boundary detection, active shape models (ASMs) are subsequently built to employ the images of entire leaves based on a priori knowledge using landmark. Two deformable models were developed with pepper leaves: Boundary-ASM and MLP-ASM. Matching processes are carried out by deforming the trained leaf models to fit real leaf images collected in the greenhouse. MLP-ASM detected 76.7 and 87.8% of overlapping and occluded pepper leaves respectively, while Boundary-ASM showed detection rates of 63.4 and 76.7%. The detection rates by the conventional ASM were 23.3 and 29.3%. The leaf models trained with pepper leaves were further tested with leaves of paprika, in the same family but with more complex shapes (e.g., holes and rolling). Although the overall detection rates were somewhat lower than those for pepper, the rates for the occluded and overlapping leaves of paprika were still higher with MLP-ASM (ranging from 60.4 to 76.7%) and Boundary-ASM (ranging from 50.5 to 63.3%) than using the conventional active shape model (from 21.6 to 30.0%). The modified active shape models with the boundary classifier could be an efficient means for detecting multiple leaves in field conditions.
Xia, M.,Tang, Z.,Kim, W.S.,Yu, T.,Park, B.J. North-Holland Pub. Co 2017 Journal of crystal growth Vol.469 No.-
In the synthesis of nanoparticles, the reaction rate is important to determine the morphology of nanoparticles. We investigated morphology evolution of Cu nanoparticles in this two different reactors, microemulsion reactor and batch reactor. In comparison with the batch reactor system, the enhanced mass and heat transfers in the emulsion system likely led to the relatively short nucleation time and the highly homogeneous environment in the reaction mixture, resulting in suppressing one or two dimensional growth of the nanoparticles. We believe that this work can offer a good model system to quantitatively understand the crystal growth mechanism that depends strongly on the local monomer concentration, the efficiency of heat transfer, and the relative contribution of the counter ions (Br<SUP>-</SUP> and Cl<SUP>-</SUP>) as capping agents.
Analysis on running safety of train on bridge with wind barriers subjected to cross wind
T. Zhang,H. Xia,W.W. Guo 한국풍공학회 2013 한국풍공학회지 Vol.17 No.2
An analysis framework for vehicle-bridge dynamic interaction system under turbulent wind is proposed based on the relevant theory of wind engineering and dynamics. Considering the fluctuating properties of wind field, the stochastic wind velocity time history is simulated by the Auto-Regressive method in terms of power spectral density function of wind field. The bridge is represented by three-dimensional finite element model and the vehicle by a multi-rigid-body system connected by springs and dashpots. The detailed calculation formulas of unsteady aerodynamic forces on bridge and vehicle are derived. In addition, the form selection of wind barriers, which are applied as the windbreak measures of newly-built railways in northwest China, is studied based on the suggested evaluation index, and the suitable values about height and porosity rate of wind barriers are studied. By taking a multi-span simply-supported box-girder bridge as a case study, the dynamic response of the bridge and the running safety indices of the train traveling on the bridge with and without wind barriers are calculated. The limit values of train speed with respect to different wind velocities are proposed according to the allowance values in the design code.
Analysis on running safety of train on bridge with wind barriers subjected to cross wind
Zhang, T.,Xia, H.,Guo, W.W. Techno-Press 2013 Wind and Structures, An International Journal (WAS Vol.17 No.2
An analysis framework for vehicle-bridge dynamic interaction system under turbulent wind is proposed based on the relevant theory of wind engineering and dynamics. Considering the fluctuating properties of wind field, the stochastic wind velocity time history is simulated by the Auto-Regressive method in terms of power spectral density function of wind field. The bridge is represented by three-dimensional finite element model and the vehicle by a multi-rigid-body system connected by springs and dashpots. The detailed calculation formulas of unsteady aerodynamic forces on bridge and vehicle are derived. In addition, the form selection of wind barriers, which are applied as the windbreak measures of newly-built railways in northwest China, is studied based on the suggested evaluation index, and the suitable values about height and porosity rate of wind barriers are studied. By taking a multi-span simply-supported box-girder bridge as a case study, the dynamic response of the bridge and the running safety indices of the train traveling on the bridge with and without wind barriers are calculated. The limit values of train speed with respect to different wind velocities are proposed according to the allowance values in the design code.
Measurement of neutron cross sections and resonance parameters of <sup>169</sup>Tm below 100 eV
Wen-Ming, Wang,Xia, Li,Zhi-Xiang, Zhao,Zu-Ying, Zhou,Hong-Wei, Yu,Hai-Cheng, Wu,Yi-Xiang, Wei,Wang, T. F.,Kim, G. N.,Lee, M. W.,Kim, K. S.,Cho, M. H.,Ko, I. S.,Namkung, W. science press 2010 Chinese physics. C Vol.34 No.2
<P>The neutron total cross-sections of thulium (<SUP>169</SUP>Tm) were measured in the neutron energy region from 0.01 eV to 100 eV by using the time-of-flight method at the Pohang Neutron Facility, which consists of an electron linac, a water-cooled tantalum target with a water moderator, and a 12 m time of flight path. Two thulium plates with different thicknesses were used for the neutron transmission measurement. The background level was determined by using a notch-filter of Co, In, and Cd sheets. The present measurement was compared with the previous ones, and a new set of resonance parameters of <SUP>169</SUP>Tm isotope was obtained from the transmission rate by using the SAMMY code, with a comparison with the recommended parameters by Mughabghab.</P>