http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
The Dynamic Mechanical Properties for Recycled Aggregate Concrete under Tensile-Compressive States
Zhen-Jun He,Zhi-qiang Wang,Meng-jia Ding,Zhen-wei Wang,Xiao-jie Zhang,Lian-shuo Liu 대한토목학회 2020 KSCE Journal of Civil Engineering Vol.24 No.5
The experiments under biaxial tensile-compressive (T-C) complex stress were carried out for two kinds of substitution percentages of recycled coarse aggregate (RCA) on biaxial proportional loading (α = σ1:σ3 =1:0, 0: -1, 0.05: -1, 0.1: -1, 0.25: -1, 0.5: -1, 1: -1 and-1: -1) and four loading deformation rates of 10−5/s, 10−4/s , 10−3/s, and 10−2/s. The research was completed in the static-dynamic true triaxial machine. The experimental phenomena indicate the tensile failure appears in these specimens of recycled aggregate concrete (RAC) under biaxial T-C stress states. The dynamic mechanical behavior for RAC under biaxial T-C loadings was affected by the strain rates, stress ratios and its substitution percentages of RCA. Accompanied by the increase of strain rates, its strength of RAC is improved. As the tensile stress increases, its compressive strength decreases. The T-C strengths for RAC under biaxial T-C states are less than its corresponding uniaxial T-C strengths at a certain identical strain rates, respectively. Considering the effect of loading rates, a new tensile-compressive failure criterion is established under complex stress states.
Strength criterion of plain recycled aggregate concrete under biaxial compression
Zhen-Jun He,Gan-Wen Liu,Wan-Lin Cao,Chang-Yang Zhou,Zhang Jia-Xing 사단법인 한국계산역학회 2015 Computers and Concrete, An International Journal Vol.16 No.2
This paper presents results of biaxial compressive tests and strength criterion on two replacement percentages of recycled coarse aggregate (RPRCA) by mass for plain structural recycled aggregate concrete (RAC) at all kinds of stress ratios. The failure mode characteristic of specimens and the direction of the cracks were observed and described. The two principally static strengths in the corresponding stress state were measured. The influence of the stress ratios on the biaxial strengths of RAC was also analyzed. The experimental results showed that the ratios of the biaxial compressive strength 3f to the corresponding uniaxial compressive strength c for the two RAC are higher than that of the conventional concrete (CC), and dependent on the replacement percentages of recycled coarse aggregate, stress states and stress ratios; however, the differences of tensile-compressive ratios for the two RAC and CC are smaller. On this basis, a new failure criterion with the stress ratios is proposed for plain RAC under biaxial compressive stress states. It provides the experimental and theoretical foundations for strength analysis of RAC structures subject to complex loads.
Inpatients' Knowledge about Primary Liver Cancer and Hepatitis
He, Wen-Jing,Xu, Ming-Yan,Xu, Rui-Rui,Zhou, Xiao-Qiong,Ouyang, Jun-Jie,Han, Hui,Chen, Geng-Zhen Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.8
Objective: To assess the level of an inpatient population's awareness about hepatitis and primary liver cancer (PLC), the most common type of which is hepatocellular carcinoma (HCC), and then to initiate education of this group. Methods: A survey was conducted with 1300 participants within the inpatient unit in representative tertiary hospitals in the Chaoshan area of China. Structured questionnaires contained demographic data and statements about different aspects of liver cancer and hepatitis. The questionnaires were completed by trained medical practitioners after they had conducted the interviews. Results: One way ANOVA showed that the sample population lacked adequate knowledge about HCC and hepatitis. Stepwise multiple regression analysis demonstrated that the participant's level of education had the greatest impact on their total knowledge score when other variables remained constant. Conclusions: The study demonstrated: a general lack of awareness amongst the participants about the preventative strategies, and the management options available for people with primary liver cancer and hepatitis; education level was an important factor affecting knowledge levels. The demonstrated deficiencies in people's knowledge about hepatitis and HCC, and their lack of subsequent protective behaviours are likely to play an important role in HCC and hepatitis transmission or prevention.
Comparison between Field Test and Numerical Analysis for a Jacket Platform in Bohai Bay, China
HE-ZHEN YANG,HAN-IL PARK,KYUNG-SIK CHOI,HUA-JUN LI 한국해양공학회 2006 韓國海洋工學會誌 Vol.20 No.2
This paper presents a comparison between numerical analysis and field test on a real offshore platform in Bohai Bay, China. This platform is a steel jacket offshore platform with vertical piles. The field testing under wave-induced force and wind force etc. was conducted, in order to obtain the dynamic parameters of the structure, including the frequencies of the jacket platform, as well as the corresponding damping ratios and mode shapes. The natural excitation technology (NExT) combined with eigensystem realization algorithm (ERA) and the peak picking (PP) method in frequency domain are carried out for modal parameter identification under operational conditions. The three-dimensional finite element model (FEM) is constructed by ANSYS and an analytical modal analysis is performed to generate modal parameters. The analytical results were compared with experimental results. A good agreement was achieved between the finite element and analysis and field test results. It is further demonstrated that the numerical and experimental modal analysis provide a comprehensive study on the dynamic properties of the jacket platform. According to the analysis results, the modal parameters identification under ambient excitation can calibrate finite element model of the jacket platform structures, or can be used for the structural health monitoring system.
STRONG CONVERGENCE OF EXTENDED GENERAL VARIATIONAL INEQUALITIES AND NONEXPANSIVE MAPPINGS
Jun-Min Chen,Li-Juan Zhang,Zhen He 영남수학회 2010 East Asian mathematical journal Vol.26 No.1
In this paper, we suggest and analyze some three step iterative scheme for finding the common elements of the set of the solutions of the extended general variational inequalities involving three operators and the set of the fixed points of nonexpansive mappings. We also consider the convergence analysis of suggested iterative schemes under some mild conditions. Since the extended general variational inequalities include general variational inequalities and several other classes of variational inequalities as special cases, results obtained in this paper continue to hold for these problems. Results obtained in this paper may be viewed as a refinement and improvement of the previously known results.
STRONG CONVERGENCE OF EXTENDED GENERAL VARIATIONAL INEQUALITIES AND NONEXPANSIVE MAPPINGS
Chen, Jun-Min,Zhang, Li-Juan,He, Zhen The Youngnam Mathematical Society 2010 East Asian mathematical journal Vol.26 No.1
In this paper, we suggest and analyze some three step iterative scheme for finding the common elements of the set of the solutions of the extended general variational inequalities involving three operators and the set of the fixed points of nonexpansive mappings. We also consider the convergence analysis of suggested iterative schemes under some mild conditions. Since the extended general variational inequalities include general variational inequalities and several other classes of variational inequalities as special cases, results obtained in this paper continue to hold for these problems. Results obtained in this paper may be viewed as a refinement and improvement of the previously known results.
ON REES MATRIX REPRESENTATIONS OF ABUNDANT SEMIGROUPS WITH ADEQUATE TRANSVERSALS
Gao, Zhen Lin,Liu, Xian Ge,Xiang, Yan Jun,Zuo, He Li Korean Mathematical Society 2009 대한수학회논문집 Vol.24 No.4
The concepts of *-relation of a ($\Gamma$-)semigroup and $\bar{\Gamma}$-adequate transversal of a ($\Gamma$-)abundant semigroup are defined in this note. Then we develop a matrix type theory for abundant semigroups. We give some equivalent conditions of a Rees matrix semigroup being abundant and some equivalent conditions of an abundant Rees matrix semigroup having an adequate transversal. Then we obtain some Rees matrix representations for abundant semigroups with adequate transversals by the above theories.
Wu, Zhen-Guo,Li, Jun-Tao,Zhong, Yan-Jun,Guo, Xiao-Dong,Huang, Ling,Zhong, Ben-He,Agyeman, Daniel-Adjei,Lim, Jin-Myoung,Kim, Du-ho,Cho, Maeng-hyo,Kang, Yong-Mook American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.25
<P>A synergistic approach for advanced cathode materials is proposed. Sodium manganese oxide with a layered-tunnel hybrid structure was designed, synthesized, and subsequently investigated. The layered-tunnel hybrid structure provides fast Na ion diffusivity and high structural stability thanks to the tunnel phase, enabling high rate capability and greatly improved cycling stability compared to that of the pure P2 layered phase while retaining the high specific capacity of the P2 layered phase. The hybrid Structure provided a decent discharge capacity of 133.4 mAh g(-1) even at 8 C, which exceeds the reported hest rate capability for Mn-based cathodes. It also displayed an impressive cycling stability, maintaining 83.3 mAh g(-1) after 700 cycles at 10 C. Theoretical calculation and the potentiostatic intermittent titration technique (PITT) demonstrated that this hybrid structure helps enhance Na ion diffusivity during charge and discharge, attaining, as a result, an unprecendented electrochemical performance.</P>