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A dynamic signal coordination control method for urban arterial roads and its application

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 907-918页

作者： Guo-jiang SHEN Yong-yao yang College of Computer Science and Technology Zhejiang University of Technology Zhejiang Zheda Supcon Information Technique Co. Ltd.

We propose a novel dynamic traffic signal coordination method that takes account of the special traffic flow characteristics of urban arterial roads. The core of this method includes a control area division module and a signal coordination control module. Firstly, we analyze and model the influences of segment distance, traffic flow density, and signal cycle time on the correlation degree between two neighboring intersections. Then, we propose a fuzzy computing method to estimate the correlation degree based on a hierarchical structure and a method to divide the control area of urban arterial roads into subareas based on correlation degrees. Subarea coordination control arithmetic is used to calculate the public cycle time of the control subarea, up-run offset and down-run offset of the section, and the split of each intersection. An application of the method in Shaoxing City, Zhejiang Province, China shows that the method can reduce the average travel time and the average stop rate effectively.

关键词： Urban arterial Control subarea Coordination control Correlation degree Fuzzy logic Intelligent transportation

Motorization and Governance in America and Its Implications for China

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学术界 2014年第5期 259-266页

作者： yao yang Guangzhou Academy of Social Sciences Guangzhou Guangdong 510410

This thesis reviews the motorization of America in 20th century and studies the public governance dealing with negative impacts of motorization. The study respectively examines auto air pollution and the Clean Air Act in America,energy consumption and CAF regulations,road safety and FMVSS,traffic congestion and the traffic congestion mitigation. The fundamental objective of the thesis is to serve as a wake- up call and policy suggestions for Chinese government to mitigate the negative impacts of motorization.

关键词：中国政府机动化美国治理空气污染交通拥堵能源消耗道路安全

Urban Motorization and Traffic Congestion Challenge in the City of Beijing：Application of A Formal Policy Analysis Paradigm

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学术界 2015年第5期 279-285页

作者： yao yang Guangzhou Academy of Social Sciences Guangzhou Guangdong 510410

Public policy is the intersection of social,cultural,political,and economic *** thesis apply a formal paradigm of policy analysis widely used in America for analyzing urban motorization and traffic congestion challenge in the city of Beijing,beginning with problem identification formation of alternative policy responses,and methods of selecting the most appropriate policy response.

关键词：城市机动化交通拥堵北京市应用公共政策反应

Numerical Simulation on Ceramic/Metal Armours Impacted by Deformable Projectile

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上海交通大学学报 2004年第z2期38卷 142-146页

作者： Zhang Xiaoqing yao Xiaohu yang Guitong College of Traffic and Communications South China University of Technology China College of Traffic and Communications South China University of Technology China Institute of Applied Mechanics Taiyuan University of Technology China Institute of Applied Mechanics Taiyuan University of Technology China

Numerical simulation for the dynamic response of ceramic/metal armours impacted by deformable projectile is carried out with *** simulated penetration processes are shown. The mushrooming of the projectile is displayed. A distinct conoid shaped zone of fragmented ceramic is observed. A significant bending of the backing plate is revealed. Simulation results match fairly well with the experimental values and the theoretical analysis results. The accuracy of the numerical simulation is validated.

关键词： deformable projectile ceramic/metal armours numerical simulation

A review of geometric calibration for different 3-D X-ray imaging systems

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Nuclear Science and Techniques 2016年第3期27卷 194-204页

作者： yang,yao Li,Liang Chen,Zhi-Qiang Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

A precise knowledge of geometry is always pivotal to a 3-D X-ray imaging system,such as computed tomography(CT),digital X-ray tomosynthesis,and computed *** get an accurate and reliable reconstruction image,exact knowledge of geometry is ***,geometric calibration has become a necessary step after completing CT system *** geometric calibration methods have been reported with the fast development of 3-D X-ray imaging *** these methods,different measuring methods,calibration phantoms or markers,and calculation algorithms were involved with their respective advantages and *** paper reviews the history and current state of geometric calibration methods for different3-D X-ray imaging *** calibration algorithms are presented and summarized,followed by our discussion and outlook.

关键词： X射线成像系统几何校正三维计算机断层扫描计算机层析成像 X射线成像技术综述校准方法

Particle agglomeration and inhibition method in the fluidized pyrolysis reaction of waste resin

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Chinese Journal of Chemical Engineering 2024年第3期67卷 135-147页

作者： Congjing Ren Peng Zhang Qi Song Zhengliang Huang yao yang Yongrong yang Ningbo Innovation Center Zhejiang UniversityNingbo 315100China College of Chemical and Biological Engineering Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture TechnologyZhejiang UniversityHangzhou 310027China

This work investigated the pyrolysis reaction of waste resin in a fluidized bed *** was found that the pyrolysis-generated ash would adhere to the surface of ceramic particles,causing particle agglomeration and *** kaolin could effectively inhibit the particle agglomeration during the fluidized pyrolysis reaction through physical isolation and chemical *** the one hand,kaolin could form a coating layer on the surface of ceramic particles to prevent the adhesion of organic ash generated by the pyrolysis of *** the other hand,when a sufficient amount of kaolin(-0.2%(mass))was added,the activated kaolin could fully contact with the Na+ ions generated by the pyrolysis of resin and react to form a high-melting aluminosilicate mineral(nepheline),which could reduce the formation of low-melting-point sodium sulfate and thereby avoid the agglomeration of ceramic particles.

关键词： Pyrolysis reaction of waste resin Fluidization Particle agglomeration Kaolin

Design and Properties of Fluoroelastomer Composites via Incorporation of MWCNTs with Varied Modification

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Chinese Journal of Polymer Science 2020年第9期38卷 983-992,I0007页

作者： Guang-yao yang Li-Fen Tong Xiao-Bo Liu Research Branch of Advanced Functional Materials School of Materials and EnergyUniversity of Electronic Science and Technology of ChinaChengdu 610054China

Multi-walled carbon nanotubes(MWCNTs)modified with silane coupling agent A-1120(MWCNTs-A1120)were *** with the raw MWCNTs,acidified MWCNTs(MWCNTs-COOH),and MWCNTs grafted with EDA(MWCNTs-NH2),MWCNTs-A1120 have the best dispersion in fluoroelastomer at the same doping ***,fluoroelastomer/MWCNTs-A1120 composite has the best mechanical properties with tensile strength of 13.92 MPa and elongation at break of 111.78%.Then,the effects of doping amount of MWCNTs-A1120 on the electrical properties of the composites were *** dielectric constant of the composite increases with the increase of MWCNTs-A1120,and the dielectric loss does not change much at the low doping amount such as 0.5 wt%.When the doping amount of MWCNTs-A1120 is 5 wt%,the dielectric constant and the dielectric loss value are greatly increased,and the volume resistivity is greatly decreased,which proves that the conductive network is formed in the composite,so the filling amount of 5 wt%is the percolation *** tensile deformation of the sample also affects the electrical properties of the *** the tensile deformation increases,the dielectric constant and dielectric loss of the composite *** the composite with 5 wt%MWCNTs-A1120,excessive tensile deformation will destroy the conductive network structure of the composite,so the composite will change from conductive material to dielectric ***,such composite is a good candidate for flexible conductive material or flexible dielectric material used in harsh environments such as high temperatures and various aggressive solvents.

关键词： Modified-MWCNTs Fluoroelastomer nanocomposite Interface compatibility Dielectric properties Volume resistivity

Dose reconstruction with Compton camera during proton therapy via subset-driven origin ensemble and double evolutionary algorithm

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Nuclear Science and Techniques 2023年第4期34卷 135-148页

作者： Zhi-yang yao Yong-Shun Xiao Ji-Zhong Zhao Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle&Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

Compton camera-based prompt gamma(PG) imaging has been proposed for range verification during proton therapy. However, a deviation between the PG and dose distributions, as well as the difference between the reconstructed PG and exact values, limit the effectiveness of the approach in accurate range monitoring during clinical applications. The aim of the study was to realize a PG-based dose reconstruction with a Compton camera, thereby further improving the prediction accuracy of in vivo range verification and providing a novel method for beam monitoring during proton therapy. In this paper, we present an approach based on a subset-driven origin ensemble with resolution recovery and a double evolutionary algorithm to reconstruct the dose depth profile(DDP) from the gamma events obtained by a cadmium-zinc-telluride Compton camera with limited position and energy resolution. Simulations of proton pencil beams with clinical particle rate irradiating phantoms made of different materials and the CT-based thoracic phantom were used to evaluate the feasibility of the proposed method. The results show that for the monoenergetic proton pencil beam irradiating homogeneous-material box phantom,the accuracy of the reconstructed DDP was within 0.3 mm for range prediction and within 5.2% for dose prediction. In particular, for 1.6-Gy irradiation in the therapy simulation of thoracic tumors, the range deviation of the reconstructed spreadout Bragg peak was within 0.8 mm, and the relative dose deviation in the peak area was less than 7% compared to the exact values. The results demonstrate the potential and feasibility of the proposed method in future Compton-based accurate dose reconstruction and range verification during proton therapy.

关键词： Prompt gamma imaging Dose reconstruction Range verification Origin ensemble Compton camera Evolutionary algorithm

Development and preliminary results of a large-pixel two-layer LaBr_(3) Compton camera prototype

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Nuclear Science and Techniques 2023年第8期34卷 100-114页

作者： Ming-Hao Dong Zhi-yang yao Yong-Shun Xiao Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

Lanthanum bromide(LaBr_(3))crystal has a high energy resolution and time resolution and has been used in Compton cameras(CCs)over the past few ***,LaBr_(3) crystal arrays are difficult to process because LaBr_(3) is easy to crack and break;thus,few LaBr_(3)-based CC prototypes have been *** this study,we designed and fabricated a large-pixel LaBr_(3) CC prototype and evaluated its performance with regard to position,energy,and angular *** used two 10×10 LaBr_(3) crystal arrays with a pixel size of 5 mm×5 mm,silicon photomultipliers(SiPMs),and corresponding decoding circuits to construct our ***,a framework based on a Voronoi diagram and a lookup table was developed for list-mode projection data *** Carlo(MC)simulations based on Geant4 and experiments were conducted to evaluate the performance of our CC *** lateral position resolution was 5 mm,and the maximum deviation in the depth direction was 2.5 and 5 mm for the scatterer and absorber,*** corresponding measured energy resolu-tions were 7.65%and 8.44%,respectively,at 511 *** experimental results of ^(137)Cs point-like sources were consistent with the MC simulation results with regard to the spatial positions and full widths at half maximum(FWHMs).The angular resolution of the fabricated prototype was approximately 6°when a point-like ^(137)Cs source was centrally placed at a distance of 5 cm from the *** proposed and investigated a large-pixel LaBr_(3) CC for the first time and verified its feasibility for use in accurate spatial positioning of radiative sources with a high angular *** proposed CC can satisfy the requirements of radiative source imaging and positioning in the nuclear industry and medical applications.

关键词： Compton camera Large pixel Gamma camera LaBr_(3)detector Prototype evaluation