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The Degree Distribution of the Random Multigraphs

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Acta Mathematica Sinica,Engli.h Series 2012年第5期28卷 941-956页

作者： Ai li.n CHEN Fu Ji ZHANG Hao li College of Mathematics and Computer Science Fuzhou University School of Mathematical Sciences Xiamen University Laboratoire de Recherche en Informatique UMR 8623C.N.R.S.-Universitde Paris-sud

In this paper, as a generali.ation of the binomial random graph model, we define the model of multigraphs as follows： let G（n; {pk}） be the probabili.y space of all the labelled loopless multigraphs with vertex set V = {v1, v2, ..., vn }, in which the distribution of tvi,vj, the number of the edges between any two vertices vi and vj is P{tvi,vj =k}=Pk, k=0, 1,2,...and they are independent of each other. Denote by Xd = Xd（G）,Yd = Yd（G）, Zd = Zd（G） and Zcd = Zcd（G） the number of vertices of G with degree d, at least d, at most d and between c and d. In this paper, we discuss the distribution of Xd, Yd, Zd and Zcd in the probabili.y space G（n; （Pk））.

关键词： Degree distribution random multigraph degree sequence

Analytic Initial Relative Orbit Solution for Angles-Only Space Rendezvous Using Hybrid Dynamics Method

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Computer Modeli.g in Engineering & Sciences 2020年第1期122卷 221-234页

作者： Baichun Gong Shuang li.li.i Zheng Jinglang Feng Nanjing University of Aeronautics and Astronautics Nanjing210016China Beijing Institute of Aerospace System Engineering Beijing100076China University of Strathclyde GlasgowG11XQScotland

A closed-form solution to the angles-only initial relative orbit determination(IROD)problem for space rendezvous with non-cooperated target is developed,where a method of hybrid dynamics with the concept of virtual formation is introduced to analytically solve the *** is placed on developing the solution based on hybrid dynamics(i.e.,Clohessy-Wiltshire equations and two-body dynamics),obtaining formation geometries that produce relative orbit state observabili.y,and deriving the approximate analytic error covariance for the IROD solution.A standard Monte Carlo simulation system based on two-body dynamics is used to verify the feasibili.y and evaluate the performance proposed *** sensitivity of the solution accuracy to the formation geometry,observation numbers is presented and discussed.

关键词： Space rendezvous relative orbit determination angles-only measurement covariance analysis

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金属橡胶复合隔振器的动静态性能

福州大学学报（自然科学版） 2024年第1期52卷 69-76页

作者：任志英梁盛涛李金明白鸿柏赖福强福州大学机械工程及自动化学院金属橡胶与振动噪声研究所福建福州350108

设计一种对称式金属橡胶与线弹簧复合的隔振器,基于整体隔振,考虑安装板的柔性因素,建立相应的等效线性动力学模型.通过准静态力学试验,分析线弹簧刚度、金属橡胶密度和加载位移对金属橡胶复合隔振器准静态性能的影响.同时,进行随机振... 详细信息

设计一种对称式金属橡胶与线弹簧复合的隔振器,基于整体隔振,考虑安装板的柔性因素,建立相应的等效线性动力学模型.通过准静态力学试验,分析线弹簧刚度、金属橡胶密度和加载位移对金属橡胶复合隔振器准静态性能的影响.同时,进行随机振动试验,研究金属橡胶复合隔振器在整体隔振中的隔振性能.试验结果表明,复合样件的刚度特性趋向于线性效果.金属橡胶复合隔振器在谐振点处的峰值衰减是线弹簧隔振器的5倍以上,且系统的随机振动响应在频段0.12~2.00 kHz内都有较大程度的衰减.

关键词：金属橡胶复合隔振器线弹簧整体隔振随机振动

基于SEM-SD的城市轨道交通产业链演化驱动因素研究

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综合运输 2024年第6期46卷 3-8页

作者：薛锋李焱茹周琳梁洁林西南交通大学交通运输与物流学院成都611756 西南交通大学综合交通大数据应用技术国家工程实验室成都611756 西南交通大学综合交通运输智能化国家地方联合工程实验室成都611756

新常态经济背景下经济增长放缓,城市轨道交通发展是应对突然危机时减缓经济下滑的重要抓手,城市轨道交通产业链根据国家政策和市场需求转型升级迫在眉睫,因此对城市轨道交通产业链演化的关键驱动因素进行研究对城市轨道交通产业具有重... 详细信息

新常态经济背景下经济增长放缓,城市轨道交通发展是应对突然危机时减缓经济下滑的重要抓手,城市轨道交通产业链根据国家政策和市场需求转型升级迫在眉睫,因此对城市轨道交通产业链演化的关键驱动因素进行研究对城市轨道交通产业具有重要意义。本文筛选出政府、技术、市场、企业和相关产业五个驱动因素及对应的观测指标,构建结构方程模型与系统动力学模型,对城市轨道交通产业链演化的关键驱动因素进行研究。结果表明,驱动因素中企业因素重要度最高,观测指标中城市轨道交通产业链演化对政府因素中的鼓励措施敏感性最高。

关键词： SEM-SD模型城市轨道交通产业链驱动因素

Robust adaptive control of hypersonic fli.ht vehicle with asymmetric AOA constraint

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Science China(Information Sciences) 2020年第11期63卷 195-207页

作者： Yuyan GUO Bin XU Weixin HAN Shuai li.Yueping WANG Yu ZHANG School of Automation Northwestern Polytechnical University Department of Computing The Hong Kong Polytechnic University Fli.ht Automatic Control Research Institute State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang University

This paper investigates the state-constrained controller design of a hypersonic fli.ht vehicle(HFV) based on an asymmetric barrier Lyapunov function(ABLF). The robust adaptive back-stepping controller with integral terms is appli.d for the HFV longitudinal dynamics. Considering the asymmetric angle of attack(AOA) constraint caused by the unique structure and scramjet, the controller is modified by constructing an ABLF, where the asymmetric constraint on AOA tracking error is introduced. Combined with the constraint on virtual control, the AOA is restricted to a predefined asymmetric interval. The system stabili.y and the AOA constraint are guaranteed via Lyapunov analysis. Simulation results verify that the AOA can be kept in the given asymmetric interval while the altitude reference signal is tracked.

关键词： hypersonic fli.ht vehicle HFV integral back-stepping control adaptive control asymmetric barrier Lyapunov function ABLF angle of attack (AOA) constraint

不同牙周状态正畸力诱导IL-23在牙周组织表达的实验研究

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中华口腔正畸学杂志 2013年第4期20卷 186-190页

作者：陈莉李小彤范晓川 Weixq 厉松北京首都医科大学口腔医学院 100050 北京大学口腔医院·口腔医学院 100081 De.ntalSchool CardiffUniversityUKI

目的研究不同牙周状态正畸力作用下IL-23在牙周组织的表达变化,为牙周病正畸治疗提供参考.方法建立大鼠牙周炎静止期、牙周炎活动期模型,以50克力移动牙周正常组、牙周炎静止期组、牙周炎活动期组的上颌磨牙.分别于牙齿移动的第3和7... 详细信息

目的研究不同牙周状态正畸力作用下IL-23在牙周组织的表达变化,为牙周病正畸治疗提供参考.方法建立大鼠牙周炎静止期、牙周炎活动期模型,以50克力移动牙周正常组、牙周炎静止期组、牙周炎活动期组的上颌磨牙.分别于牙齿移动的第3和7天处死大鼠.采用免疫组化和实时荧光定量PCR定性定量分析各组IL-23在牙周组织的表达.结果正常牙周移动组IL-23mRNA的表达较正常对照组差异无显著性（P＞0.05）.静止期牙齿移动组IL-23mRNA在牙周组织的表达较正常牙周移动组增高,差异有显著性（P＜0.05）;较活动期移动组显著减小（P＜0.01）.牙周炎活动期牙齿移动组IL-23mRNA的表达较其他各组均高,且差异有高度显著性（P＜0.01）.结论 IL-23参与调节牙周炎正畸牙齿移动.牙周炎静止期正畸治疗不会导致IL-23的过度高表达,但要密切控制牙周易感因素.

关键词：白细胞介素-23(IL-23) 牙周炎正畸牙齿移动免疫组化染色实时荧光定量PCR

The Cretaceous tectonic event in the Qiangtang Basin and its impli.ations for hydrocarbon accumulation

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Petroleum Science 2010年第4期7卷 466-471页

作者： li.Yali. Wang Chengshan li.Yongtie Ma Chao Wang li.heng Peng Shaonan State Key Laboratory of Geological Processes and Mineral Resources Research Center for Tibetan Plateau Geology China University of Geosciences Beijing 100083 China Petroleum Exploration and Development Research Institute PetroChina Beijing 100083 China

The tectonic event during Cretaceous and its relationship with hydrocarbon accumulation in the Qiangtang Basin is discussed based on zircon U-Pb dating and the study of deformation, thermochronology and hydrocarbon formation. LA-ICPMS zircon U-Pb dating indicates that the tectonic event took place during the Early-Late Cretaceous （125-75Ma）. The event not only establi.hed the framework and the styles of structural traps in the basin, but also led to the cessation of the first hydrocarbon formation and the destruction of previous oil pools. The li.ht crude oil in the basin was formed during the second hydrocarbon formation stage in the Cenozoic, and ancient structural traps formed during the Cretaceous event are promising targets for oil and gas exploration.

关键词： Qinghai-Tibet plateau Qiangtang Basin tectonic event Cretaceous hydrocarbon accumulation

Modeli.g and simulation methods of sea clutter based on measured data

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International Journal of Modeli.g, Simulation, and Scientific Computing 2021年第1期12卷 73-86页

作者： Rui Wang Xiangyang li.Zhili.Zhang Hongguang Ma Rocket Force University of Engineering Xi’an 710025 ShaanxiP.R.China School of Marine Science and Technology Northwestern Polytechnical University Xi’an 710072

The modeli.g and simulation of sea clutter are important in detecting radar targets in sea *** the nonstationary property of sea clutter is ignored in traditional statistical models,a new method based on measured sea clutter is proposed in this ***,we convert the measured sea clutter data under different sea conditions[xI,xq]into real ampli.ude *** phaseθis then extracted from the coherent radar’s baseband ***,we select a candidate statistic model and estimate its parameters based on SM by utili.ing maximum li.eli.ood ***,we generate random series A using corresponding random data generator and then add instantaneous phaseθinto A,i.e.,y=Ae^(jθ),to obtain simulated sea clutter *** a comparison of simulated sea clutter and measured sea clutter data via histogram,the vali.ity of the proposed method is proved.

关键词： Modeli.g and simulation sea clutter nonstationary time series histogram instantaneous ampli.ude and phase

A classification-based method to estimate event-related potentials from single trial EEG

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Science China(li.e Sciences) 2012年第1期55卷 57-67页

作者： HUANG ZhiHua li.MingHong ZHOU ChangLe MA YuanYe Cognitive Science Department Xiamen UniversityXiamen 361005China Fujian Key Laboratory of the Brain-li.e Intelli.ent Systems(Xiamen University) Xiamen 361005China College of Mathematics and Computer Science Fuzhou UniversityFuzhou 350108China Kunming Institute of Zoology Chinese Academy of SciencesKunming 650223China

A novel method based on machine learning is developed to estimate event-related potentials from single trial electroencephalography. This paper builds a basic framework using classification and an optimization model based on this framework for estimating event-related potentials. Then the SingleTrialEM algorithm is derived by introducing a logistic regression model, which could be obtained by training before SingleTrialEM is used, to instantiate the optimization model. The simulation tests demonstrate that the proposed method is correct and soli.. The advantage of this method is verified by the comparison between this method and the Woody filter in simulation tests. Also, the cognitive test results are consistent with the conclusions of cognitive science.

关键词： classification spatial-temporal signal model optimization logistic regression SingleTrialEM