摘要：
In order to study the creep characteristics of the coarse-grained soil as embankment filler under long-term vehicle loading, the creep test was performed on coarse-grained soil using the large scale dynamic and static triaxial instruments, and the creep process of the coarse-grained soil sample was simulated by PFC3D software, and the internal particle motion and energy change during the deformation process were studied. The research results show that the coarse-grained soil embankment filler has non-linear creep characteristics. At a low stress level, the coarse-grained soil is in the stage of elastic deformation. At a high stress level, the final creep deformation curve of the coarse-grained soil does not converge. The creep process is a process in which the particles are distorted and rotated, changing from an unstable state to a stable state. During this process, the particle energy is dissipated to the minimum, and the creep of the sample reaches a stable state. This understanding of particle motion and energy changes during the triaxial creep test of coarse-grained soil will help deepen the understanding of creep characteristics of coarse-grained soil and provide a reference for engineering practice.
期刊：
Journal of Controlled Release,2017年259:e170-e171 ISSN：0168-3659
通讯作者：
Heping Li<&wdkj&>Jun Chen
作者机构：
[Liu, Yi; Li, Heping] Changsha Univ Sci & Technol, Key Lab Rd Struct & Mat, Hunan Prov Key Lab Mat Protect Elect Power & Tran, Minist Transport, Changsha 410114, Hunan, Peoples R China.;[Hu, Yi; Lan, Aiping; Liu, Yi; Lu, Huiru; Chen, Jun] Chinese Acad Sci, Inst High Energy Phys, Key Lab Biomed Effects Nanomat & Nanosafety, Beijing 100049, Peoples R China.
通讯机构：
[Heping Li] K;[Jun Chen] C;CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing 100049, China<&wdkj&>Key Laboratory of Road Structure and Material of Ministry of Transport, Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation, Changsha University of Science and Technology, Changsha 410114, China
会议名称：
4th Symposium on Innovative Polymers for Controlled Delivery (SIPCD)
会议名称：
8th International Conference on Road and Airfield Pavement Technology (ICPT)
会议时间：
JUL 14-18, 2013
会议地点：
Taipei, TAIWAN
会议主办单位：
[Liu, Yu] Changan Univ, Sch Highway, Xian, Shanxi, Peoples R China.^[Liu, Yu] Changan Univ, Minist Educ, Key Lab Special Area Highway Engn, Xian, Shanxi, Peoples R China.^[You, Zhanping;Yao, Hui] Michigan Technol Univ, Dept Civil & Environm Engn, Houghton, MI 49931 USA.^[Yao, Hui] Changsha Univ Sci & Technol, Sch Traff & Transportat Engn, Changsha, Hunan, Peoples R China.
关键词：
Amphibious vehicles;Finite difference method;Finite element method;Highway engineering;Pavements;Traffic surveys;Vehicle wheels;Wheels;Discrete element modeling;Discrete element simulation;Elastic contact model;Mechanical behavior;Pavement engineering;Theoretical solutions;Traffic loading;Wheelpavement interaction;Loading
摘要：
In order to design a longer-lasting pavement, it is important for pavement designers to understand the mechanism of the vehicular loading. The main objective of this paper is to present an idealized discrete element modeling of pavementwheel interaction for better understanding traffic loading conditions. The idealized model consists of three parts: a smooth surface, a wheel, and a mass. The smooth surface simulates the pavement surface, while the wheel and mass represent a vehicle wheel and its corresponding mass, respectively. The mechanical behaviors at the interaction surface are simulated through an elastic contact model, a slip model, and a viscous contact damping model. Discrete Element simulation was performed through loading the wheel with a vertical force and a torsion moment at its center. As a result, the wheel was rotated and moved forward to simulate a vehicle rolling on the pavement surface. Through analyzing the simulation results, it was found that findings of this research were comparable with theoretical solutions and those of the finite element modeling in a previous study.
摘要：
Bisphenol A (BPA) molecularly imprinted polyethersulfone (PES) membranes were prepared by a liquid–liquid phase inversion technique. The BPA template molecules were then extracted from the solidified PES membranes by ethanol. BPA aqueous solutions with various concentrations were applied to the membranes to study the sieving performance. It was indicated that the sieving coefficient of the molecularly imprinted membranes was smaller than that of the non-imprinted ones due to the specific recognition sites. With the increase of BPA initial concentrations, the binding amounts of BPA increased. The recognition coefficients of BPA were 2.43, 2.18, and 1.91 for the BPA concentrations of 50, 100, and 150 μmol/L, respectively. Furthermore, it was observed that with the increase of operation pressure, the binding amounts for the imprinted membranes decreased dramatically, which, however, does not occur for the non-imprinted ones. The recognition coefficients of BPA under the pressures of 0.01, 0.03, and 0.06 MPa were 2.18, 1.64, and 1.39, respectively.
作者机构：
[Long, Kejun] Changsha Univ Sci & Technol, Coll Traff & Transportat Engn, Changsha 410114, Hunan, Peoples R China.;[Liu, Yue] Univ Wisconsin, Dept Civil Engn & Mech, Milwaukee, WI 53201 USA.;[Han, Lee D.] Univ Tennessee, Dept Civil & Environm Engn, Knoxville, TN 37996 USA.;[Liu, Yue] Univ Wisconsin, Dept Civil Engn & Mech, POB 784, Milwaukee, WI 53201 USA.
通讯机构：
[Liu, Yue] U;Univ Wisconsin, Dept Civil Engn & Mech, POB 784, Milwaukee, WI 53201 USA.
关键词：
Driver behavior;Traffic safety;Countdown timer;Driver population;Yellow phase;Dilemma zone
摘要：
This study investigates the impact of countdown timer on driving maneuvers after the onset of yellow at signalized intersections in China. Signal phasing and traffic operations were videotaped at four comparable intersections under normal conditions in Changsha city, China. Microscopic details were extracted to yield 24 h worth of data including the onset time of yellow, the onset of red, vehicle location, and maneuvers after the onset of yellow. The difference in driver’s stop/go decisions at the countdown and non-countdown timer installed intersections were investigated with binary-logistical regression analysis. By classifying the driving population into several distinct groups, this study further investigates the correlation between the countdown timer and two hazardous maneuvers: aggressive acceleration and conservative (abrupt) stopping, respectively. The descriptive results, though preliminary, indicate that the countdown timer can better assist drivers in their decision-making process and thus may reduce hazardous driving maneuvers during the phase transition period.
摘要：
In this study, pH-sensitive polyethersulfone (PES) hollow fiber membrane was prepared by blending a copolymer of poly (styrene-alt-maleic anhydride) (PSMA). The PSMA alternating copolymer was synthesized by a traditional synthetic route, and was characterized by Fourier transform infrared spectroscopy (FOR) analysis, nuclear magnetic resonance (H-1 NMR) and gel permeation chromatography technique (GPC). The PES/PSMA membrane was then transformed to carboxylic PES/PSMA-H carboxylic membrane using sodium hydroxide solution, by which the anhydride groups were transformed to carboxyl groups, and the modified membranes showed excellent pH-sensitivity and pH-reversibility. Furthermore, the alternating copolymer modified PES hollow fiber membranes showed evident hysteresis of water flux, for which it would take several hours to reach the equilibrium state. (C) 2012 Elsevier B.V. All rights reserved.
摘要：
In this study, a novel triblock copolymer of poly (styrene-co-acrylic acid)-b-poly (vinyl pyrrolidone)-b-poly(styrene-co-acrylic acid) (P(St-co-AA)-b-PVP-b-P(St-co-AA)) is synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization, and used for the modification of blood contacting surface of polyethersulfone (PES) membrane to improve blood compatibility. The synthesized block copolymer can be directly blended with PES to prepare PES membranes by a liquid-liquid phase separation technique. The compositions and structure of the PES membranes are characterized by thermogravimetric analysis (TGA), ATR-FTIR, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM); the surface charge density of the modified PES membrane was measured by Zeta-potential: the blood compatibility of the PES membranes was assessed by detecting bovine serum albumin (BSA) and bovine serum fibrinogen (BFG) adsorption, platelet adhesion, activated partial thromboplastin time (APTT), platelet activation, and thrombin-antithrombin III (TAT) generation. The results indicated that the blood compatibility of the modified PES membrane was improved due to the membrane surface modification by blending the amphiphilic block copolymer and the surface segregation of the block copolymer. (C) 2012 Elsevier B.V. All rights reserved.
作者：
Heping Yang;Yanqiang Liu;Wentao Zhan;Jie Xiao;Xiao Ni
作者机构：
[Heping Yang] Professor, School of Communication and Transportation Engineering, Changsha University of Science and Technology.E-mail:;[Yanqiang Liu; Wentao Zhan; Xiao Ni] Graduate student, School of Communication and Transportation Engineering, Changsha University of Science and Technology.E-mail:;[Jie Xiao] Doctoral Candidate, School of Communication and Transportation Engineering, Changsha University of Science and Technology.E-mail:
会议名称：
2011 GeoHunan International Conference - Instrumentation, Testing, and Modeling of Soil and Rock Behavior
会议时间：
9 June 2011 through 11 June 2011
会议地点：
Hunan, China
会议论文集名称：
Instrumentation, Testing, and Modeling of Soil and Rock Behavior<&wdkj&>Instrumentation, Testing, and Modeling of Soil and Rock Behavior<&wdkj&>Instrumentation, Testing, and Modeling of Soil and Rock Behavior
关键词：
China;Embankments;Expansive soils;Highways and roads
作者机构：
[Yonghan Li] Hunan Province Communications Planning, Survey & Design Institute, ChangSha, China;[Jian Zhao] School of Automotive & Mechanical Engineering, Changsha University of Science and Technology, ChangSha, China;[Sujuan Wang] Engineering Research Center of Catastrophic Prophylaxis and Treatment of Road & Traffic Safety Ministry of Education, Changsha University of Science and Technology, ChangSha, China;[Muxi Lei] School of Civil Engineering and Architecture, Changsha University of Science and Technology, China;[Zhengbao Lei] Key Laboratory of Highway Engineering, Ministry of Education, Changsha University of Science and Technology, ChangSha, China
通讯机构：
Engineering Research Center of Catastrophic Prophylaxis and Treatment of Road and Traffic Safety, Ministry of Education, Changsha University of Science and Technology, China
会议名称：
2011 Second International Conference on Mechanic Automation and Control Engineering
会议时间：
July 2011
会议地点：
Inner Mongolia, China
会议论文集名称：
2011 Second International Conference on Mechanic Automation and Control Engineering
作者机构：
[Zhengbao Lei] Engineering Research Center of Catastrophic Prophylaxis and Treatment of the and Traffic Safety, Ministry of Education, Changsha University of Science and Technology, Changsha, Hunan, China;[Bin Zheng] Key Laboratory of Highway Engineering, Ministry of Education, Changsha University of Science and Technology, Changsha, Hunan, China;[Muxi Lei] School of Civil Engineering and Architecture, Ministry of Education, Changsha University of Science and Technology, Changsha, Hunan, China;[Yiheng Liu] Shanghai University of Finance and Economics, Shanghai, China
通讯机构：
Key Laboratory of Highway Engineering, Changsha University of Science and Technology, Ministry of Education, China
会议名称：
2011 Second International Conference on Mechanic Automation and Control Engineering
会议时间：
July 2011
会议地点：
Hohhot
会议论文集名称：
2011 Second International Conference on Mechanic Automation and Control Engineering
关键词：
Data fusion;Inductance data;Intelligent Transport;Multi-sensor;Video data
