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Digital Communications and Networks 2023年第5期9卷 1070-1079页

作者： Zhenjiang Qian Rui xia Gaofei sun xiaoshuang Xing Kaijian xia School of Computer Science and Engineering Changshu Institute of TechnologySuzhou215500China Changshu Hospital of Soochow University Jiangsu215500ChangshuChina

A secure operating system in the communication network can provide the stable working environment,which ensures that the user information is not *** micro-kernel operating system in the communication network retains the core functions in the kernel,and unnecessary tasks are implemented by calling external *** to the small amount of code,the micro-kernel architecture has high reliability and *** the microkernel operating system in the communication network prototype VSOS as an example,we employ the objdump tool to disassemble the system source code and get the assembly layer *** this basis,we apply the Isabelle/HOL,a formal verification tool,to model the system *** referring to the mathematical model of finite automata and taking the process scheduling module as an example,the security verification based on the assembly language layer is *** on the Hoare logic theory,each assembly statement of the module is verified in *** verification results show that the scheduling module of VSOS has good functional security,and also show the feasibility of the refinement framework.

关键词： Assembly-level verification Finite automaton Hoare logic Isabelle/HOL Micro-kernel OS

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自动驾驶仿真测试场景生成技术研究进展

计算机工程与应用 2025年第1期61卷 59-79页

作者：孙乐乐黄松郑长友夏春艳阳真中国人民解放军陆军工程大学指挥与控制工程学院南京210007

自动驾驶系统已经成为汽车行业和计算机科学的前沿研究领域。为了确保自动驾驶系统的安全性和可靠性,对自动驾驶系统进行充分的测试是十分必要的,而仿真测试因其测试成本低、安全性高等优点,并且测试场景是自动驾驶仿真测试的关键,因此... 详细信息

自动驾驶系统已经成为汽车行业和计算机科学的前沿研究领域。为了确保自动驾驶系统的安全性和可靠性,对自动驾驶系统进行充分的测试是十分必要的,而仿真测试因其测试成本低、安全性高等优点,并且测试场景是自动驾驶仿真测试的关键,因此仿真测试场景生成是自动驾驶测试过程中不可或缺的环节。目前,已有大量学者致力于研究自动驾驶仿真测试,也有许多关于自动驾驶仿真测试的研究进展报告,但是针对于自动驾驶仿真测试场景生成的研究进展报告却寥寥无几。因此,对关于自动驾驶仿真测试场景的文献进行了全面调查,并对自动驾驶仿真测试的相关背景知识进行概述;通过调研国内外几十篇相关文献,按照自动驾驶系统的模块进行归纳总结,对现有仿真测试场景生成方法进行详细分类阐述;通过调研目前主流的仿真测试工具,对现有仿真测试工具进行分析归纳;分析了自动驾驶仿真测试领域面临的挑战和未来展望。

关键词：自动驾驶仿真测试测试场景整车测试仿真测试工具

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卷柏化学成分的分离与鉴定

沈阳药科大学学报 2011年第9期28卷 700-702页

作者：景颖张红梅张国刚于秀妍刘虹霞孙晓亚沈阳药科大学中药学院辽宁沈阳110016 中国医科大学临床医学院辽宁沈阳110001

目的研究卷柏属植物卷柏（Selaginella tamariscina（Beauv．）Spring）的化学成分。方法利用各种色谱法对卷柏的化学成分进行分离和纯化，通过理化性质和波谱数据分析进行结构鉴定。结果从卷柏中分离并鉴定了8个化合物，分别为尿苷（ur... 详细信息

目的研究卷柏属植物卷柏（Selaginella tamariscina（Beauv．）Spring）的化学成分。方法利用各种色谱法对卷柏的化学成分进行分离和纯化，通过理化性质和波谱数据分析进行结构鉴定。结果从卷柏中分离并鉴定了8个化合物，分别为尿苷（uridine，1）、垫状卷柏双黄酮（pulvinatabifla—vone，2）、selaginellin（3）、selaginellin C（4）、熊果苷（arbutin，5）、腺苷（adenosine，6）、β-谷甾醇（β-si—tosterol，7）、胡萝卜苷（daucosterol，8）。结论化合物1为首次从卷柏属植物中分离得到，化合物2—4为首次从卷柏中分离得到。

关键词：卷柏化学成分结构鉴定

Analysis on capabilities of density-based solvers within OpenFOAM to distinguish aerothermal variables in difusion boundary layer

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Chinese Journal of Aeronautics 2013年第6期26卷 1370-1379页

作者： Shen Chun sun Fengxian xia Xinlin School of Energy Science and Engineering Harbin Institute of Technology School of Power and Energy Science Harbin Engineering University

Open source feld operation and manipulation（OpenFOAM）is one of the most prevalent open source computational fluid dynamics（CFD）*** is very convenient for researchers to develop their own codes based on the class library toolbox within *** recent years,several density-based solvers within OpenFOAM for supersonic/hypersonic compressible flow are coming *** the capabilities of these solvers to capture shock wave have already been verifed by some researchers,these solvers still need to be validated comprehensively as commercial CFD *** boundary layer where diffusion is the dominant transportation manner,the convective discrete schemes＇capability to capture aerothermal variables,such as temperature and heat flux,is different from each other due to their own numerical dissipative characteristics and from viewpoint of this capability,these compressible solvers within OpenFOAM can be validated *** this paper,frstly,the organizational architecture of density-based solvers within OpenFOAM is ***,from the viewpoint of the capability to capture aerothermal variables,the numerical results of several typical geometrical felds predicted by these solvers are compared with both the outcome obtained from the commercial software Fastran and the experimental *** the computing process,the Roe,AUSM＋（Advection Upstream Splitting Method）,and HLLC（Harten-Lax-van Leer-Contact）convective discrete schemes of which the spatial accuracy is 1st and 2nd order are utilized,*** compared results show that the aerothermal variables are in agreement with results generated by Fastran and the experimental data even if the1st order spatial precision is ***,the accuracy of these density-based solvers can meet the requirement of engineering and scientifc problems to capture aerothermal variables in diffusion boundary layer.

关键词： Aerothermal variables Boundary layer Computational fluid dynamics(CFD) Heat flux Open source Supersonic

Adaptive Tracking Control for Mobile Manipulators with Stochastic Disturbances

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Journal of Systems Science & Complexity 2019年第5期32卷 1393-1403页

作者： sun Wei xia Jianwei WU Yuqiang School of Mathematics Science Liaocheng UniversityLiaocheng 252000China Key laboratory of Measurement and Control of CSE Ministry of EducationSchool of AutomationSoutheast UniversityNanjing 210096China School of Mathematics Science Liaocheng UniversityLiaocheng 252000 Institute of Automation Qufu Normal UniversityQufu 273165China

This paper investigates adaptive tracking control for mobile manipulators with stochastic disturbances and parametric uncertainties. Based on an appropriate reduced dynamic model and an adaptive law, a controller, which is provided by incorporating stochastic control theory with related adaptive technique, overcomes the problem of over-parametrization. It is shown that the designed state-feedback controllers can guarantee that the mean square of the tracking errors can be made arbitrarily small by choosing suitable design parameters. Simulation studies on the control of 2-DOF mobile manipulator shows the effectiveness of the proposed scheme.

关键词： Holonomic and noholonomic constraints mobile manipulators stochastic disturbances tracking control

Anchoring metal ions in amine-functionalized boron imidazolate framework for photocatalytic reduction of CO_(2)

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Chinese Chemical Letters 2022年第6期33卷 2915-2918页

作者： Guilan Xu Qin-Long hong Yayong sun Meng Liu Hai-xia Zhang Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Key Lab for Sport Shoes Upper Materials of Fujian Province Fujian Huafeng New Material Co.Ltd.Putian 351164China

The photocatalytic reduction of CO_(2)to energy-rich chemicals is highly appealing for alleviation of energy crisis and environment *** introduction of different active sites is a key factor to determine the reaction activity and ***,we demonstrate the metal ion-dependent performance for photocatalytic CO_(2)reduction by anchoring transition metal ions(Co^(2+)and Ni^(2+))in an amine-functionalized boron imidazolate framework(BIF-43).As a result,Ni@BIF-43 realized a high selectivity of 90.2%for the CO_(2)-to-CO,while Co@BIF-43 achieved more efficient conversion with a high CO production rate of 2036.0μmol g^(-1)h^(-1).Significantly,precise control of isolated metal site on a well-defined structure through coordination-assisted strategies enables us to better understand the specific effects of different metal-ion species on photoreduction of CO_(2)as well as the catalytic mechanism.

关键词： Metal-organic framework CO_(2)reduction Boron-imidazolate framework Photocatalysis Structure

Data-driven Detection and Identification of Line Parameters with PMU and Unsynchronized SCADA Measurements in Distribution Grids

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 261-271页

作者： Jinping sun Qifang Chen Mingchao xia School of Electrical Engineering Beijing Jiaotong University(BJTU)Beijing 100044China

Line parameters play an important role in the control and management of distribution ***,phasor measurement unit(PMU)systems and supervisory control and data acquisition(SCADA)systems coexist in distribution ***,SCADA and PMU measurements usually do not match each other,resulting in inaccurate detection and identification of line parameters based on *** solve this problem,a data-driven method is *** measurements are taken as samples and PMU measurements as the population.A probability parameter identification index(PPII)is derived to detect the whole line parameter based on the probability density function(PDF)parameters of the *** parameter identification,a power-loss PDF with the PMU time stamps and a power-loss chronological PDF are derived via kernel density estimation(KDE)and a conditional ***,the power-loss samples with the PMU time stamps and chronological correlations are generated by the two PDFs of the power loss via the Metropolis-Hastings(MH)***,using the power-loss samples and PMU current measurements,the line parameters are identified using the total least squares(TLS)*** simulations demonstrate the effectiveness of the proposed method for distribution network line parameter detection and identification.

关键词： Distribution systems line parameter detection and identification probability density function sampling algorithm the time skew of PMU and SCADA measurements

Cochannel interference cancelation for multiple access systems

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Journal of Systems Engineering and Electronics 2007年第2期18卷 223-228页

作者： Wang xia Zhu Shihua sun Delong School of Electronics and Information Engineering Xi'an Jiaotong Univ Xi'an 710049 P. R. China

Many properties of frequency-hopped spread-spectrum multiple access （FH/SSMA）, such as, robustness against frequency selective fading and jamming make it a preferred multiple access communication scheme. But cochannel interference （CCI） can seriously harm the system＇s performance. On the basis of the analysis of the CCI pattern of frequency hopped multiple access signal, a new multiuser detection algorithm for canceling the CCI in frequency hopped multiple access systems is proposed. In the proposed scheme, the CCI is canceled by first detecting the frequency hopping slot, and then classifying and regenerating the candidates of the interference pattern from the time-frequency matrix. Both the theoretical analysis and computer simulation results show that compared to the conventional detector and Mabuchi＇s detector, this new multiuser detector has lower complexity, better convergence stability, and is suitable for both additive white Gaussian noise （AWGN） channels and Rayleigh fading channels.

关键词： Communication and informance systems Cochannel interference cancellation Multiuser detection Frequency hopped.

Nanostructured ultrathin catalyst layer with ordered platinum nanotube arrays for polymer electrolyte membrane fuel cells

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Journal of Energy Chemistry 2020年第4期29卷 33-39页

作者： Ruoyi Deng Zhangxun xia Ruili sun Suli Wang Gongquan sun Division of Fuel Cells and Battery Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Fabrication of novel electrode architectures with nanostructured ultrathin catalyst layers is an effective strategy to improve catalyst utilization and enhance mass transport for polymer electrolyte membrane fuel cells (PEMFCs).Herein,we report the design and construction of a nanostructured ultrathin catalyst layer with ordered Pt nanotube arrays,which were obtained by a hard-template strategy based on ZnO,via hydrothermal synthesis and magnetron sputtering for PEMFC *** of the crystallographically preferential growth of Pt (111) facets,which was attributed to the structural effects of ZnO nanoarrays on the Pt nanotubes,the catalyst layers exhibit obviously higher electrochemical activity with remarkable enhancement of specific activity and mass transport compared with the state-of-the-art randomly distributed Pt/C catalyst *** PEMFC fabricated with the as-prepared catalyst layer composed of optimized Pt nanotubes with an average diameter of 90(±10) nm shows excellent performance with a peak power density of 6.0W/mgPt at 1 A/cm^2,which is 11.6%greater than that of the conventional Pt/C electrode.

关键词： Catalyst layer Membrane electrode assembly Platinum nanotube arrays Fuel cells

Corrosion prevention of sintered Nd-Fe-B magnet by a phosphate chemical conversion treatment

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Rare Metals 2021年第1期40卷 185-189页

作者： xia Ding Xiu-Chun Wang Kai-hong Ding Sheng-Li Cui Yong-Cong sun Mu-Sen Li Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China New Material Institute of Shandong Academy of Sciences.Jinan 250014 China Yantai Shougang Magnetic Materials Inc Yantai 265500China

The corrosion-resistant coating formed on the surface of sintered Nd-Fe-B magnet by a phosphate chemical conversion(PCC)treatment was *** morphology,phase composition and thickness of the coating were investigated by field emission scanning electron microscopy(FE-SEM),energy-dispersive spectrometer(EDS),Fourier transform infrared(FTIR)spectrometer and coating thickness *** corrosion behaviour of the phosphated magnet was evaluated by copper sulphate spot test,neutral salt spray test and electrochemical potentiodynamic polarization *** magnetic properties of the phosphated magnet were also *** experimental results show that the phosphate coating has such characteristics as dense granular growth,uniform distribution and thickness range of 10-18μ*** corrosion resistance of the magnet is significantly improved by phosphate coating without losing magnetic ***,this highly efficient PCC was a good way for increasing the corrosion resistance of the sintered Nd-Fe-B magnets.

关键词： Nd-Fe-B magnet Phosphate chemical conversion Microstructure Corrosion resistance