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CTCS-3级列控系统车载消息模拟器的设计与实现

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铁路通信信号工程技术 2021年第10期18卷 30-34页

作者：陈亮张浩吕方瑶赵琳中国铁道科学研究院集团有限公司铁道科学技术研究发展中心北京100081 中国铁道科学研究院集团有限公司通信信号研究所北京100081

无线闭塞中心(RBC)是CTCS-3级列控系统的地面核心设备,为保证在RBC的研制阶段,能够进行实验室仿真试验,保证测试结果可靠有效,研究设计车载消息模拟器,模拟车载ATP与RBC间的消息交互,设计划分与其他设备接口连接的4个功能模块,通过每个... 详细信息

无线闭塞中心(RBC)是CTCS-3级列控系统的地面核心设备,为保证在RBC的研制阶段,能够进行实验室仿真试验,保证测试结果可靠有效,研究设计车载消息模拟器,模拟车载ATP与RBC间的消息交互,设计划分与其他设备接口连接的4个功能模块,通过每个模块进行仿真研究,并基于C#语言实现具体功能。最后,通过实际测试案例中的RBC移交场景为例,验证该车载消息模拟器能够满足对RBC功能测试的需求,为RBC的设计、研发提供有效的试验环境与方法。

关键词：列控系统 CTCS-3级车载消息模拟器仿真测试无线闭塞中心列车超速防护系统

Bound-Preserving Discontinuous Galerkin Methods with Modified Patankar Time Integrations for Chemical Reacting Flows

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Communications on Applied Mathematics and Computation 2024年第1期6卷 190-217页

作者： fangyao Zhu Juntao Huang Yang Yang Department of Mathematical Sciences Michigan Technological UniversityHoughtonMI49931USA Department of Mathematics and Statistics Texas Tech UniversityLubbockTX79409USA

In this paper,we develop bound-preserving discontinuous Galerkin(DG)methods for chemical reactive *** are several difficulties in constructing suitable numerical *** of all,the density and internal energy are positive,and the mass fraction of each species is between 0 and ***,due to the rapid reaction rate,the system may contain stiff sources,and the strong-stability-preserving explicit Runge-Kutta method may result in limited time-step *** obtain physically relevant numerical approximations,we apply the bound-preserving technique to the DG *** traditional positivity-preserving techniques can successfully yield positive density,internal energy,and mass fractions,they may not enforce the upper bound 1 of the mass *** solve this problem,we need to(i)make sure the numerical fluxes in the equations of the mass fractions are consistent with that in the equation of the density;(ii)choose conservative time integrations,such that the summation of the mass fractions is *** the above two conditions,the positive mass fractions have summation 1,and then,they are all between 0 and *** time discretization,we apply the modified Runge-Kutta/multi-step Patankar methods,which are explicit for the flux while implicit for the *** methods can handle stiff sources with relatively large time steps,preserve the positivity of the target variables,and keep the summation of the mass fractions to be ***,it is not straightforward to combine the bound-preserving DG methods and the Patankar time *** positivity-preserving technique for DG methods requires positive numerical approximations at the cell interfaces,while Patankar methods can keep the positivity of the pre-selected point values of the target *** match the degree of freedom,we use polynomials on rectangular meshes for problems in two space *** evolve in time,we first read the polynomials at the Gaussian ***,suitable slope l

关键词： Compressible Euler equations Chemical reacting flows Bound-preserving Discontinuous Galerkin(DG)method Modified Patankar method

Time-domain Approach to the Performance Analysis of GPS Phase locked loop

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Chinese Journal of Electronics 2017年第2期26卷 385-391页

作者： ZHOU Hongwei JIN Tian lYU fangyao WANG lihua Beijing Institute of Tracking and Telecommunication Technology (BITTT) Department of Electronic and Information Engineering Beihang University Navigation Division of the 20 Research Institute of CECT

The frequency-domain approach is widely used in Global positioning system(GPS) receiver tracking loop performance *** realization,the Digital phase-locked loop(DPll) is *** is difference between phase errors by traditional frequency-domain analysis and real receiver output because of discretization *** order to get more precise result,this paper uses timedomain difference equations to analyze the phase tracking errors under the influence of thermal noise and the dynamic stress on different orders of *** simulation results show that the traditional frequency-domain approach has phase error deviation under long integration time(i.e.,more than 10ms),while the time-domain approach has good accordance with receiver simulation ***,the proposed time-domain approach can provide more precise solution for Pll performance analysis.

关键词： Global positioning system(GPS) Phase locked loop(Pll) time-domain approach difference equation

Variable step-size adaptive filtering algorithm based on an exponent sin function

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The Journal of China Universities of Posts and Telecommunications 2023年第1期30卷 56-65页

作者： Guan Sihai Cheng Qing Zhao Yong liu fangyao College of Electronic and Information Southwest Minzu UniversityChengdu 610225China Sichuan Vocational College of Finance and Economics Chengdu 610101China School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454003China

This paper proposes a robust adaptive filter based on the exponent sin cost to improve the capability against Gaussian or multiple types of non-Gaussian noises of the adaptive filtering algorithm when dealing with time-varying/time-invariant linear systems function exponent sin(ExpSin).Then a variable step-size(VSS)-ExpSin algorithm is extended ***,the stepsize,the convergence,and the steady-state performance of the proposed algorithm are validated *** Monte Carlo simulation results of linear system identification illustrate the principle and efficiency of this proposed adaptive filtering *** suggest that the proposed adaptive filtering algorithm has superior performance when estimating the unknown linear systems under multiple-types measurement noises.

关键词： adaptive filter the exponent sin function variable step-size time-varying/ time-invariant multiple types of noises

NiCo-lDH nanosheets strongly coupled with GO-CNTs as a hybrid electrocatalyst for oxygen evolution reaction

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Nano Research 2021年第12期14卷 4783-4788页

作者： Peiqun Yin Geng Wu Xiaoqian Wang Shoujie liu fangyao Zhou lei Dai Xin Wang Bo Yang Zhen-Qiang Yu School of Chemistry and Environmental Engineering Institute of Low-dimensional Materials Genome InitiativeShenzhen UniversityShenzhen518060China School of Chemistry and Materials Science Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei230026China School of Biomedical Engineering and Research and Engineering Center of Biomedical Materials Anhui Medical UniversityHefei230032China Key laboratory for Special Functional Materials of Ministry of Education School of MaterialsHenan UniversityKaifeng475004China Chemistry and Chemical Engineering of Guangdong laboratory Shantou515063China

The rational fabrication of highly efficient electrocatalysts with low cost toward oxygen evolution reaction(OER)is greatly desired but remains a formidable *** this work,we present a facile and straightforward method of incorporating NiCo-layered double hydroxide(NiCo-lDH)into GO-dispersed CNTs(GO-CNTs)with interconnected configuration.X-ray absorption spectroscopy(XAS)reveals the strong electron interaction between NiCo-lDH and the underlying GO-CNTs substrate,which is supposed to facilitate charge transfer and accelerate the kinetics for *** tuning the amount of CNTs,the optimized NiCo-lDH/GO-CNTs composite can achieve a low overpotential of 290 mV at 10 mA·cm^(−2) current density,a small Tafel slope of 66.8 mV·dec^(−1) and robust stability,superior to the pure NiCo-lDH and commercial RuO_(2) in alkaline *** preeminent oxygen evolution performance is attributed to the synergistic effect stemming from the merits and the intimate electron interaction between lDH and *** allows NiCo-lDH/GO-CNTs to be potentially applied in an industrial non-noble metal-based water electrolyzer as the anodic catalysts.

关键词： NiCo-lDH/GO-CNTs composite electrocatalysts oxygen evolution intimate electron interaction

Intratympanic vs systemic use of steroids as first-line treatment for sudden hearing loss:A meta-analysis of randomized,controlled trials

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Journal of Otology 2021年第3期16卷 165-177页

作者： Ting Yang Hui liu fangyao Chen An li Zhou Wang Shuangyuan Yang Shiyu Yang Wen Zhang Xi’an Medical University China Department of Otolaryngology Shaanxi Provincial People’s HospitalChina Xi’an Jiaotong University China

Background Sudden sensorineural hearing loss(SSNHl)is a common disease in otology,and steroids play an important role in its *** can be administered systemically or locally,and the efficacies of different administration routes remain *** We searched the Cochrane,EMBASE,PubMed,Web of Science,CNKI,Wanfang and Weipu databases for randomized controlled trials(RCTs)on glucocorticoid treatments for SSNHl to compare the efficacy of topical and systemic steroid *** Review Manager 5.4 software was used for synthesis of data:the rate of reported hearing improvement and change in pure-tone audiometry(PTA).Results In all the included studies,when intratympanic administration was compared to systemic therapies,the risk difference(RD)using reported hearing improvement as an outcome measure was 0.08(95%CI:0.01–0.14,I2=45%).Using PTA changes as an outcome measure in 4 studies,the mean difference(MD)was 10.43 dB(95%CI:3.68–17.18,I2=81%).Hearing improvement RD was also compared among different types of steroid,recovery criteria,follow-up times and diagnostic criteria,and showed no significant differences exception for recovery criteria(>10 dB)(RD-0.06,95%CI:0.14-0.2,I2=0%).Conclusion As the initial treatment for SSNHl,topical steroids seem to be superior to systemic steroid administration,especially in patients with contraindications to systemic steroids ***,further verification based on high-quality research is needed.

关键词： Intratympanic treatment Systemic treatment meta-Analysis Sudden sensorineural hearing loss

Simultaneous diffusion of cation and anion to access N,S cocoordinated Bi-sites for enhanced CO_(2) electroreduction

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Nano Research 2021年第8期14卷 2790-2796页

作者： Zhiyuan Wang Chun Wang Yidong Hu Shuai Yang Jia Yang Wenxing Chen Huang Zhou fangyao Zhou lingxiao Wang Junyi Du Yafei li Yuen Wu School of Chemistry and Materials Science Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Dalian National laboratory for Clean Energy Dalian 116023China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201210China Key laboratory of Construction Tailorable Advanced Functional Materials and Green Applications School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid MaterialsMinistry of EducationAnhui Graphene Engineering LaboratoryAnhui UniversityHefei 230601China

Developing highly active single-atom sites catalysts for electrochemical reduction of CO_(2) is an effective and environmental-friendly strategy to promote carbon-neutral energy cycle and ameliorate global climate ***,we develop an atomically dispersed N,S co-coordinated bismuth atom sites catalyst(Bi-SAs-NS/C)via a cation and anion simultaneous diffusion strategy for electrocatalytic CO_(2) *** this strategy,the bonded Bi cation and S anion are simultaneously diffused into the nitrogen-doped carbon layer in the form of *** Bi is captured by the abundant N-rich vacancies and S is bonded with *** at high temperature,formed the N,S co-coordinated Bi *** from the simultaneous diffusion of Bi and S,different electronegative N and S can be effectively co-coordinated with Bi,forming the uniform Bi-N_(3)S/C *** ***-SAs-NS/C exhibits a high selectivity towards CO with over 88%Faradaic efficiency in a wide potential range,and achieves a maximum FE_(CO)of 98.3%at-0.8 V *** with a current density of 10.24 mA·cm^(-2),which can keep constant with negligible degradation in 24 h continuous *** results and theoretical calculations reveal that the significantly improved catalytic performance of Bi-SAs-NS/C than Bi-SAs-N/C is ascribed to the replacement of one coordinated-N with low electronegative S in Bi-N_(4)C center,which can greatly reduce the energy barrier of the intermediate formation in rate-limiting step and increase the reaction *** work provides an effective strategy for rationally designing highly active single-atom sites;catalysts for efficient electrocatalysis with optimized electronic structure.

关键词： S,N-co-doped carbon nanotube single bismuth sites electronic structure modulation electrochemical CO_(2)reduction

A hierarchical heterostructure of CdS QDs confined on 3D ZnIn_(2)S_(4) with boosted charge transfer for photocatalytic CO_(2) reduction

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Nano Research 2021年第1期14卷 81-90页

作者： Zezhou Zhu Xiaoxia li Yunteng Qu fangyao Zhou Zhiyuan Wang Wenyu Wang Changming Zhao Huijuan Wang liqiang li Yagang Yao Qun Zhang Yuen Wu School of Nano-Tech and Nano-Bionics Hefei National Laboratory for Physical Sciences at the MicroscaleCollaborative Innovation Center of Chemistry for Energy Materials(iChEM)School of Chemistry and Materials Scienceand National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China Hefei National laboratory for Physical Sciences at the Microscale Synergetic Innovation Center of Quantum Information and Quantum PhysicsDepartment of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026China Division of Advanced Nanomaterials Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of SciencesSuzhou 215123China Center for Micro and Nanoscale Research and Fabrication University of Science and Technology of ChinaHefei 230026China

Metal sulfide based materials as photocatalysts for energy conversion are essential to produce value-added chemical fuels,but their intrinsically slow carrier dynamics and low activity are yet to be ***,we developed a unique heterogeneously nanostructured ZnIn_(2)S_(4)-CdS heterostructure that involves zero-dimensional(0D)CdS quantum dots uniformly confined on three-dimensional(3D)ZnIn_(2)S_(4)nanoflowers,which achieves an excellent catalytic performance of CO_(2) photoconversion under visible-light *** obtained hierarchical heterostructure can significantly enhance the light harvesting,shorten the migration distance of carriers,and obviously accelerate the transport of *** evidenced by the ultrafast transient absorption spectroscopy,the formed interface can effectively facilitate charge separation and *** work opens up a new avenue to carefully design the elaborate heterostructures for achieving optimal charge separation efficiency by lowering interfacial kinetic barriers and energy losses at the interface.

关键词： photocatalysis CO_(2)reduction charge transfer hierarchical heterostructure

Integrating single Ni site and PtNi alloy on two-dimensional porous carbon nanosheet for efficient catalysis in fuel cell

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Nano Research 2024年第8期17卷 6916-6921页

作者： fangyao Zhou Yaner Ruan Feng li lin Tian Mengzhao Zhu Wenan Tie Xiaoyan Tian Bo Wang Peigen liu Jie Xu Xiaoping Gao Peng li Huang Zhou Yuen Wu Key laboratory of Precision and Intelligent Chemistry University of Science and Technology of ChinaHefei 230026China Shanxi Yanchang Petroleum(Group)Co.ltd. Xian 710065China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035China

The performance of catalyst depends on the intrinsic activity of active sites and the structural characteristics of the ***,we simultaneously integrate single nickel(Ni)sites and platinum-nickel(PtNi)alloy nanoparticles(NPs)on a two-dimensional(2D)porous carbon nanosheet,demonstrating remarkable catalytic performance in the oxygen reduction reaction(ORR).The single Ni sites can activate the oxygen molecules into key oxygen-containing intermediate that is further efficiently transferred to the adjacent PtNi alloy NPs and rapidly reduced to H_(2)O,which establishes a relay catalysis between active *** porous structure on the carbon nanosheet support promotes the transfer of active intermediates between these active sites,which assists the relay catalysis by improving mass ***,the obtained catalyst demonstrates a half-wave potential of up to 0.942 V,a high mass activity of 0.54 A·mgPt^(−1),and negligible decay of activity after 30,000 cycles,which are all superior to the commercial Pt/C catalysts with comparable loading of *** theoretical calculation results reveal that the obtained catalyst with defect structure of carbon support presents enhanced relay catalytic effect of PtNi alloy NPs and single Ni sites,ultimately realizing improved catalytic *** work provides valuable inspiration for developing low platinum loading catalyst,integrating single atoms and alloy with outstanding performance in fuel cell.

关键词： two-dimensional porous carbon nanosheet Pt-based alloy single atom catalysts relay effect proton-exchange membrane fuel cells