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A general Boolean semantic modelling approach for complex and intelligent industrial systems in the framework of DES

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Journal of Systems Engineering and Electronics 2024年第5期35卷 1219-1230页

作者： xu changyi WANG Yun DUAN Yiman ZHANG Chao Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education School of Control Science and EngineeringDalian University of TechnologyDalian 116024China State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China

Discrete event system(DES)models promote system engineering,including system design,verification,and *** advancement in manufacturing technology has endowed us to fabricate complex industrial ***,the adoption of advanced modeling methodologies adept at handling complexity and scalability is ***,industrial systems are no longer quiescent,thus the intelligent operations of the systems should be dynamically specified in the *** this paper,the composition of the subsystem behaviors is studied to generate the complexity and scalability of the global system model,and a Boolean semantic specifying algorithm is proposed for generating dynamic intelligent operations in the *** traditional modeling approaches,the change or addition of specifications always necessitates the complete resubmission of the system model,a resource-consuming and error-prone *** with traditional approaches,our approach has three remarkable advantages:(i)an established Boolean semantic can be fitful for all kinds of systems;(ii)there is no need to resubmit the system model whenever there is a change or addition of the operations;(iii)multiple specifying tasks can be easily achieved by continuously adding a new ***,this general modeling approach has wide potential for future complex and intelligent industrial systems.

关键词： industrial complex system operation specifying Boolean semantic discrete event system(DES)theory intelligent operation

Formal management-specifying approach for model-based safety assessment

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Journal of Systems Engineering and Electronics 2023年第6期34卷 1589-1601页

作者： xu changyi DUAN Yiman ZHANG Chao School of Control Science and Engineering Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of EducationDalian University of TechnologyDalian 116024China State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China

In the field of model-based system assessment,mathematical models are used to interpret the system ***,the industrial systems in this intelligent era will be more *** management operations will be dynamically set,and the system will be no longer static as it is initially ***,the static model generated by the traditional model-based safety assessment(MBSA)approach cannot be used to accurately assess the *** mainly exists three ***:huge and complex behaviors make the modeling to be trivial manual;Dynamic:though there are thousands of states and transitions,the previous model must be resubmitted to assess whenever new management arrives;Unreusable:as for different systems,the model must be resubmitted by reconsidering both the management and the system itself at the same time though the management is the *** by solving the above problems,this research studies a formal management specifying approach with the advantages of agility modeling,dynamic modeling,and specification design that can be ***,three typical managements are specified in a series-parallel system as a demonstration to show the potential.

关键词： model-based safety assessment(MBSA) management availability reliability maintainability continuous time Markov chain.

Determining the moment of inertia of triaxial Mars with updated global gravity models

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地球与行星物理:英文版 2023年第6期7卷 615-619页

作者： changyi xu Yan Jiang Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The principal moments of inertia(PMIs)with the principal axes are usually taken as the dynamic figure parameters of Mars;they can be deduced from satellite-observed degree-two gravitational potentials in recent global gravity models and from the dynamic ellipticities resulting from precession *** PMIs are natural and significant for the geodetic,geophysical,and geodynamic problems of Mars,which are functions of internal density *** this study,a closed and concise formula for determining the PMIs of the entire planet and its core was developed based on the second invariants of gravity and a multipole *** deduced the polar oblateness J^(2)and the equatorial ellipticity J_(22)of Mars to be 1.9566×10^(−3)and 6.3106×10^(−5),*** preferred principal moments of inertia of Mars are A=2.66589×1036 kg·m^(2),B=2.66775×10^(36)kg·m^(2),and C=2.68125×10^(36)kg·m^(2).These values indicate that Mar is slightly *** equatorial principal moment of inertia of the Martian core is 1.46008×10^(35)kg·m^(2),accounting for~5.47%of the planet’s PMI;this result is critical for investigating the density and size of the core of Mars,and the planet’s free core nutation.

关键词： Mars principal moment of inertia dynamic ellipticity Chandler wobble core density and size

中小学县域增值评价离差模型的建构与应用——以长春净月高新区为例

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吉林省教育学院学报 2024年第8期40卷 47-53页

作者：徐长义董春艳长春净月高新区教育局吉林省第二实验学校

增值评价是国家倡导的教育评价形式,具有发展性、公平性和科学性的特点。在县域层面,增值性评价的实践操作典型案例不多,现有的增值评价模型普遍存在科学性和操作性不能兼容的问题。长春净月高新区研究开发了增值评价离差模型,用于本区... 详细信息

增值评价是国家倡导的教育评价形式,具有发展性、公平性和科学性的特点。在县域层面,增值性评价的实践操作典型案例不多,现有的增值评价模型普遍存在科学性和操作性不能兼容的问题。长春净月高新区研究开发了增值评价离差模型,用于本区域学校教育教学质量评估和绩效考核,该模型具有操作性强,涵盖面广,灵敏度高以及导向性的特点,在区域教育教学质量评估中收到良好的效果。

关键词：增值评价离差模型县域教育评价绩效考核督导评估

Micro-Newton scale variable thrust control technique and its noise problem for drag-free satellite platforms:a review

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第10期24卷 841-858页

作者： changyi xu Wenya LI xuhui LIU Yong LI Chao ZHANG School of Control Science and Engineering Dalian University of TechnologyDalian 116024China Beijing Institute of Control Engineering Beijing 100190China State Key Laboratory of Fluid Power&Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310058China

High-precision detection in fundamental space physics,such as space gravitational wave detection,high-precision earth gravity field measurement,and reference frame drag effect measurement,is the key to achieving important breakthroughs in the scientific study of fundamental space *** high-precision measurements requires high-performance satellite platforms to achieve“drag-free control”in a near“pure gravity”flight *** critical technology for drag-free control is variable thrust control at the micro-Newton *** noise is the most important technical indicator for achieving drag-free ***,there is no literature about the current status and future prospects of variable thrust control based on thrust ***,the micro-Newton variable thrust control technology and the thrust noise of the drag-free satellite platform are reviewed in this ***,the research status of micro-Newton scale variable thrust control technology and its applications to drag-free satellite platforms are ***,the noise problem is analyzed in detail and its solution is theoretically investigated in three aspects:“cross-basin flow problem,”“control problem,”and“system instability and multiple-coupled problem.”Finally,a systematic overview is presented and the corresponding suggested directions of research are *** work provides detailed understanding and support for realizing low-noise variable thrust control in the next generation of drag-free satellites.

关键词： Space physics detection Satellite platforms Drag-free control Micro-Newton scale variable thrust Thrust noise

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月球和火星重力场与岩石圈结构研究进展

地球与行星物理论评（中英文） 2024年第5期55卷 524-536页

作者：张诗雨陈波徐长仪中南大学地球科学与信息物理学院长沙410083 有色资源与地质灾害探查湖南省重点实验室长沙410083 中国科学院地质与地球物理研究所北京100029

月球和火星与地球相邻,是人类探索宇宙的始发站.对月球和火星的岩石圈结构开展深入研究,不仅可以揭示其壳幔系统组成和结构,而且有助于认识它们的起源和热演化历史,也能为地球起源和演化研究提供重要参考.近年来,随着国际深空探测的蓬... 详细信息

月球和火星与地球相邻,是人类探索宇宙的始发站.对月球和火星的岩石圈结构开展深入研究,不仅可以揭示其壳幔系统组成和结构,而且有助于认识它们的起源和热演化历史,也能为地球起源和演化研究提供重要参考.近年来,随着国际深空探测的蓬勃发展,月球和火星重力场模型的精度与分辨率越来越高.基于重力数据的月球和火星岩石圈结构研究取得了一系列重要科学进展.本文简单介绍了月球和火星的探测计划和重力场模型,进而详细介绍了利用重力数据在月球和火星岩石圈结构研究中取得的成果.最后,本文对月球和火星岩石圈结构研究进行了总结和展望,提出了突破重力场在行星岩石圈结构研究中不确定性的方法,希望能对推动月球和火星重力场探测及岩石圈结构的研究进程提供帮助.

关键词：月球和火星探测重力场岩石圈结构

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Implicit expansion rate of the Earth in global plate motions

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Geodesy and Geodynamics 2019年第3期10卷 228-234页

作者： changyi xu Xiao Yu Dongping Wei Institute of Earthquake Forecasting China Earthquake AdministrationBeijingChina Institute of Earth Sciences Academia SinicaTaipeiTaiwan Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijingChina

Based on eight published plate motion models, we separately estimated the net area changes of tectonic plates and the area change of the solid Earth surface over geological time using the Euler vectors of plates with determined boundaries. Then, under the context of a currently expanding Earth, we inferred the change rate of the Earth’s mean radius from the estimated net area changes. The results show that the total increases and decreases in the areas of different plates cannot be compensated. Specifically, the area of the Northern Hemisphere decreases while that of the Southern Hemisphere increases, but the net area of the solid Earth surface slightly increases in th computing period(0.01 Ma). For the latest NNRMORVEL56 plate motion model, the area of the Southern Hemisphere increases by 7802 km2 while the area of the Northern Hemisphere decreases by 7711 km^2. This indicates a net area increase of 91 km2 in the solid Earth surface corresponding to an expansion rate of 0.06 mm/a for the Earths mean *** result coincides with the slow rate of expansion derived from geodetic measurements and geophysical modeling.

关键词： Plate motion model Area change of plate boundary Earth expansion

基于多算法分级权重集成的渤海西岸降水预报技术研究

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海洋预报 2024年第3期41卷 71-79页

作者：侯敏杨晓君王彩霞张楠许长义王国松天津市海洋气象重点实验室天津300074 天津市滨海新区气象局天津300450 天津市气象台天津300074 国家海洋信息中心天津300171

以渤海西岸为研究区域,基于2019—2021年6—9月实况降水资料和模式预报数据,研发了一种新的降水集成预报技术,采用分级权重分配将3种客观订正预报算法和6种集合统计量算法进行集成,得到多算法分级权重集成预报(Hierarchical-weight Cons... 详细信息

以渤海西岸为研究区域,基于2019—2021年6—9月实况降水资料和模式预报数据,研发了一种新的降水集成预报技术,采用分级权重分配将3种客观订正预报算法和6种集合统计量算法进行集成,得到多算法分级权重集成预报(Hierarchical-weight Consensus Forecasting,HCF),然后以2021年9月渤海西岸一次典型强降水过程为例进行了检验评估。结果表明:HCF预报(08时—次日08时)的所有降水量级的TS评分均高于欧洲中期天气预报中心(ECMWF)的模式预报;相较于ECMWF模式预报和其他客观预报,HCF在降水量级和落区预报方面均表现良好,08时—次日08时的大雨及以上量级的TS评分最高,其他降水量级检验评估指标也均在前三位;在个例检验中,HCF预报较ECMWF模式的所有降水量级的检验指标均更优秀,其中小雨预报的TS评分较ECMWF模式提升41.76%,大雨预报评分提升54.42%。

关键词：沿海降水预报分级权重集成晴雨订正个例检验

类地行星低阶重力场、自转与内部圈层结构研究进展

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地球与行星物理论评（中英文） 2024年第5期55卷 552-562页

作者：徐长仪万妍姜衍魏勇中国科学院地球与行星物理重点实验室北京100029 中国科学院地质与地球物理研究所北京100029 中国科学院大学地球与行星科学学院北京100049

低阶重力场和自转参数是类地行星内部结构的函数且指示着其物质成分与演化,一直是深空探测的首要目标.行星自转状态能够直接揭示行星核的密度和大小.随着深空探测数据的逐渐积累和精度的不断提高,低阶重力场和自转观测在行星内部结构,... 详细信息

低阶重力场和自转参数是类地行星内部结构的函数且指示着其物质成分与演化,一直是深空探测的首要目标.行星自转状态能够直接揭示行星核的密度和大小.随着深空探测数据的逐渐积累和精度的不断提高,低阶重力场和自转观测在行星内部结构,尤其是行星核方面的研究取得了一系列重要进展.本文首先介绍行星主惯性矩张量的基本理论与计算方法,接着介绍行星自转动力学基本理论以及与行星内部结构密切相关的行星自转简正模,并介绍利用低阶重力位系数求解行星主惯性矩张量的方法.本文还总结了利用有限的自转观测和低阶重力场观测确定行星平均密度和平均惯性矩的研究现状,以及反演行星内部结构的基本方法.最后,本文对目前利用低阶重力场、自转观测反演行星和小行星等内部结构方面存在的问题进行了总结与展望,希望为我国未来的深空探测计划提供科学参考与理论支持.

关键词：类地行星内部结构自转动力学低阶重力场行星核大小和密度

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