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Electrical and Piezoresistive Properties of Steel Fiber Cement-based Composites Aligned by a Magnetic Field

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Journal of Wuhan University of Technology(Materials Science) 2022年第2期37卷 229-240页

作者： liu liyuan XU Jinxia WANG Yang YIN Tianjiao CHU Hongqiang College of Mechanics and Materials Hohai UniversityNanjing 211100China

Directionally distributed steel fiber cement-based composites(SFCCs)were prepared by magnetic field(MF)induction *** orientation factor of steel fibers in the as-obtained SFCCs was ***,the electrical resistivity and piezoresistive responses in two directions of aligned steel fiber cement-based composites,i e,parallel and perpendicular to MF,were *** effects of several variables,eg,steel fiber content,curing age,humidity,and temperature,on anisotropic electrical property were *** cyclic and failure piezoresistive responses in different directions were *** is found that the aligned steel fibers in the as-obtained SFCCs have a high orientation factor more than ***,SFCCs with aligned steel fibers exhibit an obvious anisotropic conductivity and piezoelectric *** electrical conductivity of SFCCs with aligned steel fibers is less affected by temperature and *** the steel fiber content of 2.5wt%,the piezoelectric sensitivity coefficient of SFCCs in the direction parallel to MF has the highest value of *** addition,the piezoresistive properties of SFCCs with aligned steel fibers in the direction parallel to MF indicate excellent sensitivity and stability under cyclic loading and monotonic loading.

关键词： electrical resistivity aligned steel fiber piezoresistivity cement-based composites

An Improved Training Algorithm Based on Ensemble Penalized Cox Regression for Predicting Absolute Cancer Risk

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China CDC weekly 2023年第9期5卷 206-212,I0009-I0014页

作者： liyuan liu Fu Yang Yeye Fan Chunyu Kao Fei Wang Lixiang Yu Yong He Jiadong Ji Zhigang Yu Department of Breast Surgery The Second HospitalCheeloo College of MedicineShandong UniversityJinan CityShandong ProvinceChina School of Mathematics Shandong UniversityJinan CityShandong ProvinceChina Zhongtai Securities Institute for Financial Studies Shandong UniversityJinan CityShandong ProvinceChina Institute of Translational Medicine of Breast Disease Prevention and Treatment Shandong UniversityJinan CityShandong ProvinceChina.

Introduction:Biases in cancer incidence characteristics have led to significant imbalances in databases constructed by prospective cohort *** they use imbalanced databases,many traditional algorithms for training cancer risk prediction models perform ***:To improve prediction performance,we introduced a Bagging ensemble framework to an absolute risk model based on ensemble penalized Cox regression(EPCR).We then tested whether the EPCR model outperformed other traditional regression models by varying the censoring rate of the simulated ***:Six different simulation studies were performed with 100 *** assess model performance,we calculated mean false discovery rate,false omission rate,true positive rate,true negative rate,and the areas under the receiver operating characteristic curve(AUC)*** found that the EPCR procedure could reduce the false discovery rate(FDR)for important variables at the same true positive rate(TPR),thereby achieving more accurate variable *** addition,we used the EPCR procedure to build a breast cancer risk prediction model based on the Breast Cancer Cohort Study in Chinese Women *** for 3-and 5-year predictions were 0.691 and 0.642,representing improvements of 0.189 and 0.117 over the classical Gail model,***:We conclude that the EPCR procedure can overcome challenges posed by imbalanced data and improve the performance of cancer risk assessment tools.

关键词： Cancer false prediction

Research on Human-Vehicle-Road Friendliness Based on Improved SH-GH-ADD Control

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Sound & Vibration 2023年第1期57卷 45-68页

作者： Yangyang Bao Mingliang Yang Haibo Huang liyuan liu Honglin Zhu Weiping Ding School of Mechanical Engineering Southwest Jiaotong UniversityChengdu610031China

The hub-driven virtual rail train is a novel urban transportation system that amalgamates the benefits of modern trams and ***,this system is plagued by issues such as decreased ride comfort and severe deformation of urban roads due to the increase in sprung mass and long-term rolling at the same *** address these concerns and improve the human-vehicle-road friendliness of the virtual rail train,we propose an Improved Sky-Ground Hook and Acceleration-Driven Damper control(Improved SH-GH-ADD control)strategy for the semi-active suspension *** control monitors the vibration acceleration signal of the unsprung mass in real-time and selects the mixed Sky-Hook and Acceleration-Driven Damper(SH-ADD)control or the mixed Ground-Hook and Acceleration-Driven Damper(GH-ADD)control based on the positive and negative values of the vibration acceleration of the unsprung *** Improved SH-GH-ADD control combines the advantages of SH-ADD control and GH-ADD control to achieve control of the sprung mass and unsprung mass in the full fre-quency ***,through simulation and comparative analysis with traditional SH-ADD,GH-ADD,and mixed SH-GH control,we demonstrate the exceptional performance of the proposed algorithm.

关键词： SH control GH control ADD control ride comfort road friendliness

Asymmetric coherent rainbows induced by liquid convection

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Chinese Physics B 2021年第12期30卷 450-454页

作者： Tingting Shi Xuan Qian Tianjiao Sun Li Cheng Runjiang Dou liyuan liu Yang Ji State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China College of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Coherent rainbows can be formed by focusing white-light laser into *** are bilaterally symmetric interference rings with various *** interference rings arise from the temperature distribution of the liquid induced by laser heating,i.e.,thermal lens effect,which changes the refractive index locally and thus the optical path *** up-down asymmetry of the interference rings is caused by convection in the *** the increase of the viscosity,the interference rings change their shape from oval to circular *** a shutter is opened and the laser shines into the liquid,the interference rings are circular at the *** time goes on,they gradually turn into an oval *** the liquid go a free-fall at the beginning,the interference rings remain *** the three experiments have confirmed that the asymmetric interference rings are due to convection in the liquid associated with thermal lens *** also numerically simulate the two-dimensional heat conduction with and without convection,whose results agree well with our experimental observations.

关键词： coherent interference thermal lens effect convection numerical simulation

Breast Cancer Awareness and Association with Frequency of Screening Among Women—China,2020

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China CDC weekly 2023年第15期5卷 327-332页

作者： Heling Bao liyuan liu Shu Cong Fei Wang Lixiang Yu Liwen Fang Xuening Duan Feng Tan Zhigang Yu Linhong Wang Institute of Medical Information Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina National Center for Chronic and Non-communicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina The Second Hospital of Shandong University Jinan CityShandong ProvinceChina Peking University First Hospital BeijingChina Chinese Center for Disease Control and Prevention BeijingChina

Summary What is already known about this topic?Breast cancer awareness plays a crucial role in promoting screening attendance,enabling early detection,and improving survival rates associated with breast ***,a persiste... 详细信息

关键词： Breast Cancer awareness

Interaction of colliding laser pulses with gas plasma for broadband coherent terahertz wave generation

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Photonics Research 2023年第9期11卷 1562-1569页

作者： YUXUAN CHEN YUHANG HE liyuan liu ZHEN TIAN JIANMING DAI Center for Terahertz Waves and School of Precision Instrument and Opto-electronics Engineering Tianjin UniversityTianjin 300072China

Colliding of two counter-propagating laser pulses is a widely used approach to create a laser field or intensity *** experimentally demonstrate broadband coherent terahertz(THz)radiation generation through the interaction of colliding laser pulses with gas *** THz radiation has a dipole-like emission pattern perpendicular to the laser propagation direction with a detected peak electric field 1 order of magnitude higher than that by single pulse *** a proof-of-concept demonstration,it provides a deep insight into the physical picture of laser–plasma interaction,exploits an important option to the promising plasma-based THz source,and may find more applications in THz nonlinear near-field imaging and spectroscopy.

关键词： laser coherent interaction

Depressive Symptoms and Sleep Duration as Risk Factors for Breast Cancer—China,2020

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China CDC weekly 2023年第15期5卷 333-339页

作者： liyuan liu Heling Bao Fei Wang Lixiang Yu Shu Cong Fei Zhou Yujuan Xiang Shuya Huang Chao Zheng Liwen Fang Linhong Wang Zhigang Yu Department of Breast Surgery The Second Hospital of Shandong UniversityJinan CityShandong ProvinceChina Institute of Translational Medicine of Breast Disease Prevention and Treatment Shandong UniversityJinan CityShandong ProvinceChina Institute of Medical Information Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina National Center for Chronic and Noncommunicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina

Summary What is already known about this topic?Psychological and lifestyle factors are known to potentially play a significant role in the development of breast ***,current evidence-based studies present controversial... 详细信息

关键词： breast Breast Cancer

Research on the Efficiency Evaluation for the Board Based on GT-AHP Method

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Journal of Systems Science and Information 2006年第4期4卷 783-790页

作者： Ligen Yao Tao liu liyuan Ren Lei liu School of Economics and Management Hebei University of Engineering Handan 056038 China

The board of directors is the core of corporate governance mechanism. In order to enhance the operation efficiency of the board, and to further reduce the agency cost, effective appraisal of the efficiency of the board becomes urgent. This paper firstly uses graph transformation and matrix algorithm to analyze the performance evaluation factors of the board and establishes the ordered hierarchy structure of the appraisal indexes. Then, it calculates the index weights with the AHP method. Next, it sets up the efficiency appraisal index system of the board. At last, the paper gives an empirical analysis with an example.

关键词： AHP board efficiency efficiency evaluation GT

The Status of Organochlorine Pesticides Pollution in Hubei Section of the Yangtze River

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地学前缘 2009年第S1期16卷 81-82页

作者： Chen liu,liyuan Guo School of the Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China.

The Organochlorine Pesticides(OCPs),such as hexachlorocyclohexane(HCH)and dichlorodiphenyltrichloro ethane(DDT),are well known as typical persistent organic pollutions(POPs).They were worldwide used several decades ago,even today in some *** the water resource is very important in natural environments and essential to agriculture,the pollution of OCPs in water has emerged as worldwide environmental problem. Wuhan section of the Yangtze River is the drinking water source of Wuhan area in Hubei *** addition,Hubei province is an important production base of grain,cotton,oil and *** the rapid development of industry and mass-use of OCPs

关键词： organochlorine pesticides Yangtze River water residues