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Dependence patterns associated with the fundamental diagram:a copula function approach

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第1期11卷 18-24页

作者： jia LI Yue-ping XU Department of Ctvtl and Envzronmental Engtneermg University of Massachusetts Amherst Amherst MA 01002 USA Department of Civil Engmeermg Zhejlang Umverslty Hangzhou 310058 China)

Randomness plays a major role in the interpretation of many interesting traffic flow phenomena,such as hysteresis,capacity drop and spontaneous breakdown. The analysis of the uncertainty and reliability of traffic systems is directly associated with their random characteristics. Therefore,it is beneficial to understand the distributional properties of traffic variables. This paper focuses on the dependence relation between traffic flow density and traffic speed,which constitute the fundamental diagram (FD). The traditional model of the FD is obtained essentially through curve fitting. We use the copula function as the basic toolkit and provide a novel approach for identifying the distributional patterns associated with the FD. In particular,we construct a rule-of-thumb nonparametric copula function,which in general avoids the mis-specification risk of parametric approaches and is more efficient in practice. By applying our construction to loop detector data on a freeway,we identify the dependence patterns existing in traffic data. We find that similar modes exist among traffic states of low,moderate or high traffic densities. Our findings also suggest that highway traffic speed and traffic flow density as a bivariate distribution is skewed and highly heterogeneous.

关键词： Nonparametric copula Dependence patterns Traffic flow Loop detector

基于数据挖掘技术对氟喹诺酮类药物相关神经系统不良反应的分析研究

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中国药物应用与监测 2017年第5期14卷 285-288,320页

作者：杨鸿溢贾王平郭代红范琦赵粟裕重庆医科大学药学院重庆400016 解放军总医院医保部药品保障中心北京100853

目的:挖掘和评价氟喹诺酮类药物(FQNs)中相关神经系统药品不良反应(ADR)的风险信号,为临床提供用药参考。方法:调取解放军ADR数据库中FQNs相关ADR报告,对涉及神经系统ADR报告相关信息进行统计分析,并采用比例报告比法、报告比值比法、... 详细信息

目的:挖掘和评价氟喹诺酮类药物(FQNs)中相关神经系统药品不良反应(ADR)的风险信号,为临床提供用药参考。方法:调取解放军ADR数据库中FQNs相关ADR报告,对涉及神经系统ADR报告相关信息进行统计分析,并采用比例报告比法、报告比值比法、英国药品和保健产品管理局的综合标准法和贝叶斯可信区间递进神经网络法4种数据挖掘方法,获取FQNs相关神经系统ADR风险信号,及中枢神经系统(CNS)和周围神经系统(PNS)的风险信号。结果:研究共纳入2008年7月到2017年6月期间FQNs相关的有效ADR报告11 988例,涉及神经系统的1322例。相关FQNs共14种,其中引发神经系统ADR频次最高的前5种药物为左氧氟沙星、莫西沙星、加替沙星、环丙沙星和依诺沙星。出现神经系统ADR阳性信号的药物为莫西沙星、氟罗沙星和芦氟沙星。结论:FQNs相关神经系统ADR的主要引发药物为莫西沙星、氟罗沙星和芦氟沙星,应针对性强化临床应用中相关警戒意识并予以防范。

关键词：氟喹诺酮类神经系统药品不良反应药物警戒数据挖掘

Combined Effects of 50 Hz Magnetic Field and Magnetic Nanoparticles on the Proliferation and Apoptosis of PC12 Cells

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Biomedical and Environmental Sciences 2014年第2期27卷 97-105页

作者： jia Hong Li wang Chao LI Yue LU Yan wang ping ping PAN Wei Dong SONG Tao Beijing Key Laboratory of Bioelectromagnetism Institute of Electrical Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Basic Theory Shandong Sport University

Objective To investigate the bioeffects of extremely low frequency （ELF） magnetic field （MF）（50 Hz, 400 μT） and magnetic nanoparticles （MNPs） via cytotoxicity and apoptosis assays on PC12 cells. Methods MNPs modified by SiO2 （MNP-SiO2） were characterized by transmission electron microscopy （TEM）, dynamic light scattering and hysteresis loop measurement. PC12 cells were administrated with MNP-SiO2 with or without MF exposure for 48 h. Cytotoxicity and apoptosis were evaluated with MTI- assay and annexin V-FITC/PI staining, respectively. The morphology and uptake of MNP-SiO2 were determined by TEM. MF simulation was performed by Ansoft Maxwell based on the finite element method. Results MNP-SiO2 were identified as -20 nm （diameter） ferromagnetic particles. MNP-SiO2 reduced cell viability in a dose-dependent manner. MF also reduced cell viability with increasing concentrations of MNP-SiO2. MNP-SiO2 alone did not cause apoptosis in PC12 cells; instead, the proportion of apoptotic cells increased significantly under MF exposure and increasing doses of MNP-SiO2. MNP-SiO2 could be ingested and then cause a slight change in cell morphology. Conclusion Combined exposure of MF and MNP-SiO2 resulted in remarkable cytotoxicity and increased apoptosis in PC12 cells. The results suggested that MF exposure could strengthen the MF of MNPs, which may enhance the bioeffects of ELF MF.

关键词： Extremely low frequency magnetic field Magnetic nanoparticles Cytotoxicity Apoptosis Morphology

Si/TiO_(2) carbon fiber core encapsulated in hierarchical multiple MXene@Co-MoS_(2) shells for constructing a free-standing anode of lithium storage

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Rare Metals 2024年第9期43卷 4222-4233页

作者： Xian-ping Du Ying Huang jia-ming wang Zhen-he Feng Xu Sun MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Conditions School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shanghai Institute of Space Power-Sources Shanghai 200245China Ningbo Institute of Northwestern Polytechnical University Ningbo 315103China

Silicon-based(Si-based) materials offer more possibilities for generating new portable electronic devices due to their high specific capacities. However, their inferior electrical conductivity and volume expansion during cycling seriously limit their development. The optimum solution is to select specific materials to establish an exceptionally conductive and volume buffer structure,which can assist Si materials in developing their excellent lithium storage properties. In this study, Si particles were confined in TiO_(2)carbon fibers(TiO_(2)CFs) via electrospinning, after which they were encapsulated with MXene and Co-MoS_(2)(CMS) nanosheets to fabricate hierarchical ST-2@MXene@CMS films. TiO_(2)CF, MXene and CMS were employed to establish a coherent conductive network with one-, two-and three-dimensional electronic pathways to permit the unimpeded flow of electrons inside the electrode material. TiO_(2)CF, MXene and CMS acted precisely as multilayered buffers to ameliorate the volume change of Si particles during cycling. In addition, the CMS nanosheets were involved in lithium storage, contributing to the final electrochemical performance. Ultimately, the ST-2@MXene@CMS films served as free-standing electrodes, avoiding the impact of inactive interfaces on the electrochemical performance and fulfilling the lightweight requirement for new energy storage devices.

关键词： Si particles MXene Co-MoS_(2)nanosheets Hierarchical structure Lithium-ion batteries

Numerical simulation of supercontinuum generation based on the active nonlinear fiber

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Optoelectronics Letters 2021年第3期17卷 149-154页

作者： jia Cai-ping wang Chun-can Key Laboratory of All Optical Network and Advanced Telecommunication Network Ministry of EducationInstitute of Lightwave TechnologyBeijing Jiaotong UniversityBeijing 100044China

The supercontinuum(SC) generation(SCG) based on the active nonlinear fiber has attracted much attention due to its advantages in the energy amplification and spectral broadening of the output pulses. The active step-index single-mode fiber is proposed for the SCG. A flat normal-dispersion profile ranging from 1 240 nm to 2 550 nm can be obtained by tuning the germanium(Ge) concentration and core size, where the values of the dispersion slope are between-0.01 ps/nm^(2)/km and 0.05 ps/nm^(2)/km. Furthermore, the output pulse from the 5 m Er-doped normal-dispersion fiber(NDF) with g0=9 m^(-1) has a peak power of 2.8 kW and a 20 dB spectral bandwidth of 507 nm ranging from 1 262 nm to 1 769 nm by using the 1 550 nm and 1 ps Gaussian pulse with a peak power of 10 kW as the pumping source.

关键词： fiber tuning pumping

Arithmetic P Systems Based on Arithmetic Formula Tables

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Chinese Journal of Electronics 2015年第3期24卷 542-549页

作者： YANG Ruilong GUO ping LI jia GU ping College of Computer Science Chongqing University Chongqing Key Laboratory of Software Theory and Technology Chongqing University

Arithmetic operations are fundamental in computing models. Novel arithmetic P systems are constructed to perform four basic operations: addition, subtraction, multiplication, division. The digits of decimal integers are directly put into hierarchical membranes, one digit one membrane, thus, the number of membranes is reduced and complexity is lowered. Core evolution rules are designed for single digit operations according to the arithmetic formula tables widely used by humans. Some examples are given to illustrate how to compute decimal integers in these P systems and the results indicates that these P systems can efficiently carry out arithmetic computations of integers.

关键词： Membrane computing Arithmetic P systems Hybrid encodings Arithmetic formula tables

实时剪切波超声弹性成像对慢性乙型病毒性肝炎肝纤维化分期的定量分析

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昆明医科大学学报 2016年第11期37卷 55-59页

作者：孙月韦嘉陆永萍王锦邹玉王禹雪杨谧昆明医科大学第四附属医院云南昆明650041

目的探讨实时剪切波超声弹性成像（SWE）技术在慢性乙型病毒性肝炎肝纤维化分期诊断中的应用价值,同时建立诊断肝纤维化分期的杨氏模量值参考范围.方法以48例慢性乙肝患者和58例健康成人作为研究对象,测量研究对象的肝脏S5、S6段杨氏模... 详细信息

目的探讨实时剪切波超声弹性成像（SWE）技术在慢性乙型病毒性肝炎肝纤维化分期诊断中的应用价值,同时建立诊断肝纤维化分期的杨氏模量值参考范围.方法以48例慢性乙肝患者和58例健康成人作为研究对象,测量研究对象的肝脏S5、S6段杨氏模量值,并对48例慢性乙肝患者进行病理组织学检查,将病理结果与杨氏模量值进行比较分析,得出诊断肝纤维化分期的杨氏模量值参考范围.结果肝S5、S6段的杨氏模量值在慢乙肝组及正常对照组间存在显著差异（P〈0.05）,慢乙肝组S5、S6段杨氏模量值分别为（11.7±2.9、12.1±3.2）k Pa,明显高于正常对照组（5.7±1.1、5.8±1.3）k Pa.肝杨氏模量值在各纤维化分期间均有差异（P〈0.05）,S0-S4期肝S5段杨氏模量值分别为（5.8±2.2、7.3±1.9、10.3±2.8、10.3±2.8、25.3±3.6）k Pa,肝S6段杨氏模量值分别为（5.7±2.3、9.2±2.1、10.5±2.1、14.7±4.5、26.1±2.1）k Pa,且随S分期的增加,肝脏杨氏模量值有所增加.结论 SWE技术可确立肝纤维化分期的杨氏模量值参考范围,且有较高的敏感性、特异性和准确性.

关键词：实时剪切波弹性成像慢性乙型病毒性肝炎肝纤维化杨氏模量值

Anti-corrosive and highly reversible zinc metal anode enabled by the phenolic resin coating

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Rare Metals 2024年第5期43卷 2115-2124页

作者： Ya-ping wang Ya-Di Yang Shu-Qi Duan Li wang jia-Shuo Guo An-Qiang Pan School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Key Laboratory of Special Functional Materials for Ecological Environment and Information(Hebei University of Technology).Ministry of Education Tianjin 300130China Key Laboratory for New Type of Functional Materials in Hebei Province Hebei University of TechnologyTianjin 300130China School of Materials Science and Engineering Central South UniversityChangsha 410083China

Aqueous zinc-ion batteries have attracted much attention due to their high theoretical capacity,low cost high safety,and ***,challenges such as dendrite growth and side reactions severely hinder the electrochemical performance of the Zn anode,leading to low Coulombic efficiency(CE)or even short circuits Herein,phenolic resin(PF)is used as a protective coating on the surface of the zinc metal *** PF layer can greatly improve the corrosion resistance of the Zn electrode in the ***,this artificial electrode/electrolyte interphase also elevates the nucleation barrier and restrains Zn^(2+)2D diffusion,regulating the zinc deposition/dissolution *** a result,PF@Zn symmetric cells exhibit superior performance than that of bare Zn symmetric cells,achieving a stable and dendrite-free cycle of 1400 ***,the carbon nanotube MnO_(2)||PF@Zn(CNT/MnO_(2)||PF@Zn)full cell also delivers a long cycle life with a high-capacity retention of about 180.0 m Ah·g^(-1)after 1400 cycles,far exceeding that of bare Zn *** work provides a facile strategy for achieving a dendrite-free and rechargeable zinc anode.

关键词： Rechargeable aqueous batteries Zn metal anode Phenolic resin Anti-corrosion

Dynamic Response of A Group of Cylindrical Storage Tanks with Baffles Considering the Effect of Soil Foundation

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China Ocean Engineering 2024年第1期38卷 129-143页

作者： SUN Ying wang jia-dong HUO Rui-li ZHOU Ding GU Zhen-yuan QIAN wang-ping School of Transportation and Civil Engineering Nantong UniversityNantong 226019China Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang 212013China College of Civil Engineering Nanjing Tech UniversityNanjing 211816China

The sloshing in a group of rigid cylindrical tanks with baffles and on soil foundation under horizontal excitation is studied *** solutions for the velocity potential are derived out by the liquid subdomain *** models with mass-spring oscillators are established to replace continuous *** with the least square technique,Chebyshev polynomials are employed to fit horizontal,rocking and horizontal-rocking coupling impedances of soil,respectively.A lumped parameter model for impedance is presented to describe the effects of soil on tank structures.A mechanical model for the soil-foundation-tank-liquid-baffle system with small amount of calculation and high accuracy is proposed using the substructure *** analytical solutions are in comparison with data from reported literature and numerical codes to validate the effectiveness and correctness of the *** dynamic properties and seismic responses of the soil-tank system are given for the baffle number,size and location as well as soil parameter.

关键词： cylindrical tanks multiple annular baffles equivalent analytical model soil−structure interaction subdomain method dynamic response