• Title/Summary/Keyword: Hainan

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Experimental study of the compressive strength of chemically reinforced organic-sandy soil

  • Hu, Jun;Zhang, Lei;Wei, Hong;Du, Juan
    • Geomechanics and Engineering
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    • v.16 no.3
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    • pp.247-255
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    • 2018
  • Organic-sandy soils that contain abundant organic matters are widely encountered in estuarine cities. Due to the existence of organic matters, the strength and stiffness of this type of soil are significantly low. As a result, various geotechnical engineering problems such as difficulties in piling and constructing embankments and a lack of strength in poured concrete may occur in many estuarine sites; ground improvement such as cement treatment to this type of soils is needed. In this study, laboratory tests were performed to investigate the compressive strength of organic-sandy soil reinforced with primarily cement, in which the influences of several factors, namely types of cement and additional stabilizing agent, cement content, and water-cement ratio, were investigated and the orthogonal experimental design scheme was adopted. Based on the test results, an optimal permutation of these influencing factors is suggested for the reinforcement of organic-sandy soils, which can provide a useful reference for the relevant engineering practice.

Interaction of internal forces of interior beam-column joints of reinforced concrete frames under seismic action

  • Zhou, Hua;Zhang, Jiangli
    • Structural Engineering and Mechanics
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    • v.52 no.2
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    • pp.427-443
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    • 2014
  • This paper presents detailed analysis of the internal forces of interior beam-column joints of reinforced concrete (RC) frames under seismic action, identifies critical joint sections, proposes consistent definitions of average joint shear stress and average joint shear strain, derives formulas for calculating average joint shear and joint torque, and reports simplified analysis of the effects of joint shear and torque on the flexural strengths of critical joint sections. Numerical results of internal joint forces and flexural strengths of critical joint sections are presented for a pair of concentric and eccentric interior connections extracted from a seismically designed RC frame. The results indicate that effects of joint shear and torque may reduce the column-to-beam flexural strength ratios to below unity and lead to "joint-yielding mechanism" for seismically designed interior connections. The information presented in this paper aims to provide some new insight into the seismic behavior of interior beam-column joints and form a preliminary basis for analyzing the complicated interaction of internal joint forces.

Novel Preamble Design for Channel Estimation in FBMC/OQAM Systems

  • Wang, Han;Du, Wencai;Xu, Lingwei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.8
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    • pp.3672-3688
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    • 2016
  • The nonorthogonality between the real and imaginary FBMC/OQAM modulated signals complicates the channel estimation (CE) process, and conventional OFDM CE methods cannot be directly applied to FBMC/OQAM. The conventional preamble-based CE schemes in FBMC/OQAM systems are mainly based on the interference approximation method (IAM) to improve the estimation performance. In this paper, we develop a novel preamble structure to improve the CE performance. We exploit the symmetry pattern to cancel interference and take into account the interference weights in this symmetric structure. The conventional preamble and the proposed preamble are compared via simulations in the IEEE 802.22, 3GPP Vehicular A and Pedestrian A channels. Numerical simulation results demonstrate that the proposed preamble can achieve better bit error ratio (BER) and mean squared error (MSE) performance under the three channel models considered.

A HYBRID METHOD FOR NCP WITH $P_0$ FUNCTIONS

  • Zhou, Qian;Ou, Yi-Gui
    • Journal of applied mathematics & informatics
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    • v.29 no.3_4
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    • pp.653-668
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    • 2011
  • This paper presents a new hybrid method for solving nonlinear complementarity problems with $P_0$-functions. It can be regarded as a combination of smoothing trust region method with ODE-based method and line search technique. A feature of the proposed method is that at each iteration, a linear system is only solved once to obtain a trial step, thus avoiding solving a trust region subproblem. Another is that when a trial step is not accepted, the method does not resolve the linear system but generates an iterative point whose step-length is defined by a line search. Under some conditions, the method is proven to be globally and superlinearly convergent. Preliminary numerical results indicate that the proposed method is promising.

Alkaloid from Stemona and Lyophyllum

  • Yang Ye;Lin, Wen-han;Qin, Guo-wei;Xu, Ren-sheng;Wu, Hou-ming;Yi Zhong;Zhong, Qiong-xing;Wolfgang Steglich
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.62-65
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    • 1998
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A Dynamic Accuracy Estimation for GPU-based Monte Carlo Simulation in Tissue Optics

  • Cai, Fuhong;Lu, Wen
    • Current Optics and Photonics
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    • v.1 no.5
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    • pp.551-555
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    • 2017
  • Tissue optics is a well-established and extensively studied area. In the last decades, Monte Carlo simulation (MCS) has been one of the standard tools for simulation of light propagation in turbid media. The utilization of parallel processing exhibits dramatic increase in the speed of MCS's of photon migration. Some calculations based on MCS can be completed within a few seconds. Since the MCS's have the potential to become a real time calculation method, a dynamic accuracy estimation, which is also known as history by history statistical estimators, is required in the simulation code to automatically terminate the MCS as the results' accuracy achieves a high enough level. In this work, spatial and time-domain GPU-based MCS, adopting the dynamic accuracy estimation, are performed to calculate the light dose/reflectance in homogeneous and heterogeneous tissue media. This dynamic accuracy estimation can effectively derive the statistical error of optical dose/reflectance during the parallel Monte Carlo process.

Post-Transcriptional Control of Tropoelastin in Aortic Smooth Muscle Cells Affects Aortic Dissection Onset

  • Qi, You-Fei;Shu, Chang;Xiao, Zhan-Xiang;Luo, Ming-Yao;Fang, Kun;Guo, Yuan-Yuan;Zhang, Wen-Bo;Yue, Jie
    • Molecules and Cells
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    • v.41 no.3
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    • pp.198-206
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    • 2018
  • Aortic dissection (AD) is a catastrophic disease with high mortality and morbidity, characterized with fragmentation of elastin and loss of smooth muscle cells. Although AD has been largely attributable to polymorphisms defect in the elastin-coding gene, tropoelastin (TE), other undermined factors also appear to play roles in AD onset. Here, we investigated the effects of post-transcriptional control of TE by microRNAs (miRNAs) on elastin levels in aortic smooth muscle cells (ASMC). We found that miR-144-3p is a miRNA that targets TE mRNA in both human and mouse. Bioinformatics analyses and dual luciferase reporter assay showed that miR-144-3p inhibited protein translation of TE, through binding to the 3'-UTR of the TE mRNA. Interestingly, higher miR-144-3p levels and lower TE were detected in the ASMC obtained from AD patients, compared to those from non-AD controls. In a mouse model for human AD, infusion of adeno-associated viruses (serotype 6) carrying antisense for miR-144-3p (asmiR-144-3p) under CAG promoter significantly reduced the incidence and severity of AD, seemingly through enhancement of TE levels in ASMC. Thus, our data suggest an essential role of miR-144-3p on the pathogenesis of AD.