Utilization and Development of the Special Black Barley Resource

Zhong Xian Li,Jian Kun Xie,Si Wen Zhang,Tao Zhang 한국육종학회 1997 한국육종학회 학술발표회 발표요지 Vol.29 No.2

Analysis of a mode-I crack perpendicular to an imperfect interface

Zhong, Xian-Ci,Li, Xian-Fang,Lee, Kang Yong Elsevier 2009 International journal of solids and structures Vol.46 No.6

<P><B>Abstract</B></P><P>The elastostatic problem of a mode-I crack embedded in a bimaterial with an imperfect interface is investigated. The crack is in proximity to and perpendicular to the imperfect interface, which is governed by linear spring-like relations. The Fourier transform is applied to reduce the associated mixed-boundary value problem to a singular integral equation with Cauchy kernel. By numerically solving the resulting equation, stress intensity factors near both crack tips are evaluated. Obtained results reveal that the stress intensity factors in the presence of the imperfect interface vary between that with a perfect interface and that with a completely debonding interface. Moreover, an increase in the interface parameters decreases the stress intensity factors. In particular, when crack approaches to the weakened interface closer, the stress intensity factors become larger for a sliding interface, and become larger or smaller for a Winkler interface, depending on the crack lying in a stiffer or softer material. The influences of the imperfection of the interface on the stress intensity factors for a bimaterial composed of aluminum and steel are presented graphically.</P>

Study on the Genetic Transfer in Wheat (Triticum aestivum) and Pea (Pisum Sativum)

Zhong Xian Li,Si Wen Zhang,Jian Kun Xie,Ling Guang Luo,Tao Zhang 한국육종학회 1997 한국육종학회 학술발표회 발표요지 Vol.29 No.2

Dynamics of Yeast-like Symbiote and its Relationship with the Virulence of Brown Planthopper, Nilaparvata lugens Stal, to Resistant Rice Varieties

Zhong-Xian Lu,Xiao-Ping Yu,Jian-Ming Chen,Xu-Song Zheng,Hong-Xing Xu,Jue-Feng Zhang Zhang,Lie-Zhong Chen 한국응용곤충학회 2004 Journal of Asia-Pacific Entomology Vol.7 No.3

Abundance of the yeast-like symbiote (YLS) in brown planthopper (BPH), Nilaparvata lugens Stl, collected from rice fields in China and obtained from International Rice Research Institute (IRRI), was monitored. The role of YLS in nymph survival rate, development and adult reproduction, and activities of transaminases in BPH on different resistant rice varieties were examined. Also, the relationship between YLS and virulence shifts of BPH to resistant rice varieties was discussed. The results indicated that the virulence of BPH populations to resistant rice varieties was strongly related to the abundance of YLS in 5th instar nymphs and brachypterous females of BPH field populations at Nanning in South China and Hangzhou in East China, showing the more abundance of YLS in BPH, the higher virulence of BPH to resistant rice varieties, while no obvious differences in YLS abundance were monitored between three BPH biotypes. Numbers of YLS reduced significantly in female adult of BPH biotype 1 fed on resistant rice varieties IR26, Mudgo and ASD7, compared with that fed on susceptible rice variety TN1. The lowest YLS abundance of BPH from field population was found in 2nd generation successively fed on resistant varieties, and the number of YLS was resumed at 4th generation when the BPH has adapted the resistant varieties. The markedly lower nymphal survival rate, adult fecundity and activities of alanine and aspartic transminase, and significantly longer nymph duration in the three aposymbiotic biotypes than in the symbiotic ones were recorded on both susceptible and resistant rice varieties. However, the much greater differences between aposymbiotic and symbiotic BPH were found on the inadaptable resistant rice varieties than that on the fitness resistant rice varieties. Those results implied that YLS in BPH should play a crucial role in the virulent shift of BPH populations to resistant rice varieties.

Flexural Behavior of Circular Hollow RC Piers with Reduced Amounts of Inner Hoops

Zhong-Xian Li,Chun-yu Du,Xiao Liang,Bo Zhao 한국콘크리트학회 2020 International Journal of Concrete Structures and M Vol.14 No.2

Reversed cyclic loading tests of two circular hollow RC piers were conducted in this study to investigate the effect of different amounts of inner and outer circular hoops on their flexural behavior. The test results showed that the column with a smaller amount of inner circular hoops presented better flexural response than the as-built column with an equal amount of inner and outer circular hoops. Also, the demand developed on the inner circular hoops was smaller than the outer one within the plastic hinge regions, which verified that using a smaller amount of inner circular hoops was reasonable and effective. By examining the confining stress experienced by the concrete in the radial and circumferential directions based on a detailed theoretical analysis, a modeling approach was proposed to take the confinement effect in circular hollow RC piers into consideration. The proposed modeling approach was validated through comparisons with the experimental study and satisfactory agreement was found.

Mechanism Study of Tropical Cyclone Impact on East Asian Subtropical Upper-Level Jet: a Numerical Case Investigation

Xian Chen,Zhong Zhong,Wei Lu 한국기상학회 2018 Asia-Pacific Journal of Atmospheric Sciences Vol.54 No.4

In the case study of this paper, sensitivity experiments are carried out using the mesoscale non-hydrostaticWeather Research and Forecasting (WRF) model to investigate the impact of tropical cyclone (TC) Soudelor (2003) on the East Asian subtropical upper-level jet (EASJ) before TC Soudelor transformed into an extratropical cyclone. The physical mechanism for changes in the EASJ intensity and position caused by TC Soudelor is explored. Results indicate that TC Soudelor would warm the air in the middle and upper troposphere over the Japan Sea and the adjacent areas through stimulating northward propagating teleconnection pattern as well as releasing large amounts of latent heat, which led to increase (decrease) the meridional air temperature gradient to the south (north) below the EASJ axis. As a result, the geopotential height abnormally increased in the upper troposphere, resulting in an anomalous anticyclonic circulation belt along the EASJ axis. Correspondingly, the westerly winds to the north (south) of the EASJ axis intensified (weakened) and the EASJ axis shifted northward by one degree. The case study also suggests that before the extratropical cyclone transition of TC Soudelor, the TC activities had exerted significant impacts on the EASJ through thermodynamic processes.

Nonlocal Formulation for Numerical Analysis of Post-Blast Behavior of RC Columns

Zhong-Xian Li,Bo Zhong,Yanchao Shi,Jia-Bao Yan 한국콘크리트학회 2017 International Journal of Concrete Structures and M Vol.11 No.2

Residual axial capacity from numerical analysis was widely used as a critical indicator for damage assessment of reinforced concrete (RC) columns subjected to blast loads. However, the convergence of the numerical result was generally based on the displacement response, which might not necessarily generate the correct post-blast results in case that the strain softening behavior of concrete was considered. In this paper, two widely used concrete models are adopted for post-blast analysis of a RC column under blast loading, while the calculated results show a pathological mesh size dependence even though the displacement response is converged. As a consequence, a nonlocal integral formulation is implemented in a concrete damage model to ensure mesh size independent objectivity of the local and global responses. Two numerical examples, one to a RC column with strain softening response and the other one to a RC column with post-blast response, are conducted by the nonlocal damage model, and the results indicate that both the two cases obtain objective response in the post-peak stage.

Structural damage identification based on transmissibility assurance criterion and weighted Schatten-.. regularization

Xian Zhong,Ling Yu 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.82 No.6

Structural damage identification (SDI) methods have been proposed to monitor the safety of structures. However, the traditional SDI methods using modal parameters, such as natural frequencies and mode shapes, are not sensitive enough to structural damage. To tackle this problem, this paper proposes a new SDI method based on transmissibility assurance criterion (TAC) and weighted Schatten-p norm regularization. Firstly, the transmissibility function (TF) has been proved a useful damage index, which can effectively detect structural damage under unknown excitations. Inspired by the modal assurance criterion (MAC), TF and MAC are combined to construct a new damage index, so called as TAC, which is introduced into the objective function together with modal parameters. In addition, the weighted Schatten-p norm regularization method is adopted to improve the ill-posedness of the SDI inverse problem. To evaluate the effectiveness of the proposed method, some numerical simulations and experimental studies in laboratory are carried out. The results show that the proposed method has a high SDI accuracy, especially for weak damages of structures, it can precisely achieve damage locations and quantifications with a good robustness.

An approach to Design a Fuzzy PI controller in HVDC system

Zhong-xian Wang,Jeung-je Yang,Seok-beom Rho,Tae-chon Ahn 제어로봇시스템학회 2005 제어로봇시스템학회 국내학술대회 논문집 Vol.2005 No.10

Dynamics of Yeast-like Symbiote and Its Relationship with the Virulence of Brown Planthopper, Nilaparvata lugens Stal, to Resistant Rice Varieties

Lu, Zhong-Xian,Yu, Xiao-Ping,Chen, Jian-Ming,Zheng, Xu-Song,Xu, Hong-Xing,Zhang, Jue-Feng,Chen, Lie-Zhong Korean Society of Applied Entomology 2004 Journal of Asia-Pacific Entomology Vol.7 No.3

Abundance of the yeast-like symbiote (YLS) in brown planthopper (BPH), Nilaparvata lugens Stal, collected from rice fields in China and obtained from International Rice Research Institute (IRRI), was monitored. The role of YLS in nymph survival rate, development and adult reproduction, and activities of transaminases in BPH on different resistant rice varieties were examined. Also, the relationship between YLS and virulence shifts of BPH to resistant rice varieties was discussed. The results indicated that the virulence of BPH populations to resistant rice varieties was strongly related to the abundance of YLS in 5th instar nymphs and brachypterous females of BPH field populations at Nanning in South China and Hangzhou m East China, showing the more abundance of YLS in BPH, the higher virulence of BPH to resistant rice varieties, while no obvious differences in YLS abundance were monitored between three BPH biotypes. Numbers of YLS reduced significantly in female adult of BPH biotype 1 fed on resistant rice varieties IR26, Mudgo and ASD7, compared with that fed on susceptible rice variety TN1. The lowest YLS abundance of BPH from field population was found in 2nd generation successively fed on resistant varieties, and the number of YLS was resumed at 4th generation when the BPH has adapted the resistant varieties. The markedly lower nymphal survival rate, adult fecundity and activities of alanine and aspartic transminase, and significantly longer nymph duration in the three aposymbiotic biotypes than in the symbiotic ones were recorded on both susceptible and resistant rice varieties. However, the much greater differences between aposymbiotic and symbiotic BPH were found on the inadaptable resistant rice varieties than that on the fitness resistant rice varieties. Those results implied that YLS in BPH should playa crucial role in the virulent shift of BPH populations to resistant rice varieties.