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Multipath Estimation Using Particle Filtering with Kinematic Model of the Direct Signal

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Multipath Estimation Using Particle Filtering with Kinematic...

准噶尔盆地东道海子凹陷及周缘上古生界原油成因来源

第三届中国卫星导航学术年会

作者： Ke Chen 1 , Qingming Gui 2 1 institute of surveying and mapping, Information Engineering University, Middle Longhai Road 66, 450052.zhengzhou, china 2 institute of Science, Information Engineering University, Kexue Avenue 62, 450001 zhengzhou, china

It is difficult to characterize how multipath signal components appear and disappear and how the values of multipath parameters transform. Multipath estimation based on particle filtering is implemented using the kinematic information of the direct signal components. In the update steps of particle filtering, the parameters of the direct signal component are estimated combining observation and kinematic information while the parameters of multipath components are estimated using only observation information. The building of proposals and the implementation of the filtering are given. The method can use the kinematic information of the direct signals to improve the accuracy and meanwhile avoid misusing of the incorrect kinematic information of multipath signals. It is approved by simulations that the method proposed in this paper performs better than traditional multipath estimation based on particle filtering and the narrow correlator.

关键词： multipath multipath estimation particle filtering kinematic model direct signal

来源： cnki会议评论

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高校地质学报 2024年第2期30卷 218-230页

作者：尹晟宇龚德瑜苏静胡正舟吴卫安王瑞菊中国地质大学(北京)能源学院北京100083 中国石油勘探开发研究院北京100083 中国石油新疆油田公司勘探开发研究院克拉玛依8340003

东道海子凹陷的钻探工作始于20世纪90年代,但由于复杂的构造演化和沉积特征,该区勘探长期停滞不前。直到近期,部署在东道海子凹陷的探井中屡屡发现良好油气显示,使该区的油气勘探重燃希望。目前,对该区油气成因来源的认识还很薄弱,给勘... 详细信息

东道海子凹陷的钻探工作始于20世纪90年代,但由于复杂的构造演化和沉积特征,该区勘探长期停滞不前。直到近期,部署在东道海子凹陷的探井中屡屡发现良好油气显示,使该区的油气勘探重燃希望。目前,对该区油气成因来源的认识还很薄弱,给勘探方向的选择造成了较大的困难。文章对东道海子凹陷及周缘石炭系和二叠系储层中原油的稳定碳同位素组成、类异戊二烯烷烃和甾萜类生物标志化合物等地球化学特征进行了系统分析,划分了原油的成因类型,再结合研究区主力烃源岩的地球化学特征,最终厘清了各类原油的来源。结果表明,研究区原油总体已进入主生油窗,属于成熟原油,分为三种不同类型。第一类原油稳定碳同位素组成重,Pr/Ph值较高,含有丰富的C_(19)三环萜烷、C_(20)三环萜烷和C_(24)四环萜烷,伽马蜡烷指数低,来自下石炭统松喀尔苏组b段的淡水腐殖型烃源岩。第二类原油稳定碳同位素组成轻,Pr/Ph值相对较低,含有丰富的β-胡萝卜烷和伽马蜡烷,但C_(19)三环萜烷、C_(20)三环萜烷和C_(24)四环萜烷的丰度较低,来自中二叠统平地泉组咸水湖相烃源岩。第三类原油的地化特征介于上述两类原油之间,表现出混源特征。上述认识提供了一个在多源叠置区开展油源对比的典型案例,同时也为东道海子凹陷及周缘下一步油气勘探指明了方向。

关键词：准噶尔盆地东道海子凹陷油源对比石炭系二叠系稳定碳同位素组成生物标志化合物

Featureless Zone in Rapidly Solidified Aluminum Alloy Splats

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Journal of Materials Science & Technology 1993年第6期9卷 464-466页

作者： Ningfu SHEN Yali TANG Dongjie ZHANG Longqing CHEN Shaokang GUAN Research Centre for Materials,zhengzhou institute of Technology,zhengzhou,450002,china

The microstructures of rapidly solidified (RS) Al-Fe-Ce-Ti and Al-Fe-V-Si alloys obtained by means of rotating blade quenching were studied with optical microscopy,transmission electron microscopy (TEM).The featureless zone observed in the two alloys reveals that the new technique offers a higher solidification rate than the inert-gas-atomized *** TEM observation the featureless zone presents virtually a micropartition or partitionless feature,and the solute contents in it are almost the same as the chemical composition of alloys.

关键词： rapid solidification rotating blade quenching aluminum alloy featureless zone

A NEW METHOD OF FREQUENCY-HOPPING(FH) SIGNAL DETECTION

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Journal of Electronics(china) 2011年第4期28卷 468-473页

作者： Zeng Yu Liu Xueqian Li Ou(Information and Engineering University,Information and Engineering institute,zhengzhou 450002,china) Information and Engineering institute Information and Engineering University Zhengzhou China zhengzhou China

A new Frequency-Hopping(FH) signal detection method is *** from pre-vious methods which need to monitor the total band,it can monitor part of the band and decrease the range of the *** to this method,a new detection model is set and the computation formulas of the detection probability and false-alarm probability are *** parameters of a VHF radio are used to prove the validity of the *** results show that this method can de-crease the range of the bandwidth and detect the FH signal with some penalty on the SNR and signal loss.

关键词： Frequency-Hopping(FH) Detection Monitor Interception Channelized radiometer

Preparation of graphitic carbon nitride by electrodeposition

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Chinese Science Bulletin 2003年第16期48卷 1737-1740页

作者： LI Chao1,2, CAO Chuanbao1 & ZHU Hesun1 1. Research Center of Materials Science, Beijing institute of Technology, Beijing 100081, china 2. Department of Chemical Engineering, zhengzhou institute of Light Industry, zhengzhou 450002 china Correspondence should be addressed to Cao Chuanbao Research Center of Materials Science Beijing Institute of Technology Beijing 100081 China Department of Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China

The CNx thin film was deposited on Si(100) substrate from a saturated acetone solution of cyanuric tri-chloride and melamine (cyanuric trichloride/melamine=1︰1.5) at room temperature. X-ray diffraction (XRD) results showed that the diffraction peaks in the pattern coincided well with those of graphite-like carbon nitride calculated in the literature. The lattice constants (a=4.79 ? c=6.90 ) for g-C3N4 matched with those of ab initio calculations (a=4.74 ? c=6.72 ? quite well. X-ray photoelectron spectroscopy (XPS) measurements indicated that the elements in the de-posited films were mostly of C and N (N/C=0.75), and N (400.00 eV) bonded with C (287.72 eV) in the form of six-member C3N3 ring. The peaks at 800 cm-1, 1310 cm-1 and 1610 cm-1 in the Fourier transform infrared (FTIR) spec-trum indicated that triazine ring existed in the product. These results demonstrated that crystalline g-C3N4 was ob-tained in the CNx film.

关键词：沉淀薄膜饱和丙酮溶液三聚氰胺 X射线衍射石墨碳氮化合物晶格恒量光电子光谱测量法傅立叶变换红外光谱三嗪

Robust fault diagnosis for non-Gaussian stochastic systems based on the rational square-root approximation model

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Science in china(Series F) 2008年第9期51卷 1281-1290页

作者： YAO LiNa1 & WANG Hong2,3 1 School of Electrical Engineering,zhengzhou University,zhengzhou 450001,china 2 Control Systems Centre,University of Manchester,Manchester M60 1QD,UK 3 institute of Automation,Chinese Academy of Sciences,Beijing 100080,china School of Electrical Engineering Zhengzhou University Control Systems Centre University of Manchester institute of Automation Chinese Academy of Sciences

The task of robust fault detection and diagnosis of stochastic distribution control （SDC） systems with uncertainties is to use the measured input and the system output PDFs to still obtain possible faults information of the system. Using the rational square-root B-spline model to represent the dynamics between the output PDF and the input, in this paper, a robust nonlinear adaptive observer-based fault diagnosis algorithm is presented to diagnose the fault in the dynamic part of such systems with model uncertainties. When certain conditions are satisfied, the weight vector of the rational square-root B-spline model proves to be bounded. Conver- gency analysis is performed for the error dynamic system raised from robust fault detection and fault diagnosis phase. Computer simulations are given to demon- strate the effectiveness of the proposed algorithm.

关键词： SDC systems output probability density functions(PDFs) robust fault detection and diagnosis rational square-root B-spline functions

Combination of drainage, water supply and environmental protection as well as rational distribution of water resource in zhengzhou mining district

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Science china Earth Sciences 2005年第10期48卷 1768-1779页

作者： WU Qiang1, LI Duo1,2, DI Zhiqiang3, MIAO Ying3, ZHAO Suqi4 & GUO Qiwen5 1. Resource Exploitation Engineering College, CUMT, Beijing 100083, china 2. Shijiazhuang Engineering College, University of Economics, Shijiazhuang 050031, china 3. Shenyang institute of Geology and Mineral Resources, Shenyang 110032, china 4. State Adminstration of Coal Mine Safety, Beijing 100013, china 5. zhengzhou Coal Mine Company (Group), zhengzhou 452371, china Resource Exploitation Engineering College CUMT University of Economics Shenyang institute of Geology and Mineral Resources State Adminstration of Coal Mine Safety zhengzhou Coal Mine Company (Group)

The geological condition of coalfield is much complex in china. With increasing in mining depth and drainage amount, the contradiction of drainage, water supply and environ-mental protection is becoming more and more serious. However, the contradiction can be solved by the scientific management of optimizing combination of drainage, water supply and environ-mental protection. The Philip multiple objectives simplex method used in this article has searched for a possible solution at the first step, and then it goes on searching to find out whether there is a weight number that can lead the solution to the biggest. It can reduce the randomness and diffi-culty of traditional weight method which determine the weight number artificially. Some beneficial coefficients are vague and the number is larger in the model of water resource dispatch. So the vague layer analysis method can consider these vague factors fully, combining the qualitative and quantitative analysis together. Especially, this method can quantify the experiential judge-ment of policy decider, and it will turn to be more suitable if the structure of objective factors is complex or the necessary data are absent. In the paper, the two methods above are used to solve the plans of drainage, water supply and optimizing distribution of water resource in the zhengzhou mining district.

关键词： combination of drainage, water supply and environmental protection, Philip multiple objective simplex method, vague layer analysis method, distribution of water resource.

Variational solution about over-determined geodetic boundary value problem and its related theories

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Science china Earth Sciences 2007年第4期50卷 555-562页

作者： YU JinHai1,2 & PENG FuQing3 1 institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, china 2 College of Earth Scienc, Graduate University of Chinese Academy of Sciences, Beijing 100049, china 3 Zhenghou institute of surveying and mapping, zhengzhou 450052. china institute of Geodesy and Geophysics Chinese Academy of SciencesWuhan 430077China College of Earth Scienc Graduate University of Chinese Academy of SciencesBeijing 100049China Zhenghou institute of surveying and mapping Zhengzhou 450052China

A new solving method for Laplace equation with over-determined geodetic boundary conditions is pro- posed in the paper, with the help of minimizing some kinds of quadratic functional in calculus of variation. At first, the so-called variational solution for over-determined geodetic boundary value problem is defined in terms of principles in calculus of variation. Then theoretical properties related with the solution are derived, especially for its existence, uniqueness and optimal approximation. And then the computational method of the solution is discussed, and its expression is exhibited under the case that all boundaries are spheres. Finally an arithmetic example about EGM96 gravity field model is given, and the computational results show that the proposed method can efficiently raise accuracy to deal with gravity data. In all, the variational solution of over-determined geodetic boundary value problem can not only fit to deal with many kinds of gravity data in a united form, but also has strict mathematical basements.

关键词： earth’s gravity field over-determined boundary value problem quadratic functional. variational solution optimal approximation

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卫星双向时间比对及其误差分析

天文学进展 2004年第3期22卷 219-226页

作者：刘利韩春好信息工程大学测绘学院郑州450052 中国科学院测量与地球物理研究所武汉430077

介绍了卫星双向时间比对(TWSTT)方法的发展过程及其基本原理,讨论了TWSTT的误差源,分析了各误差源对比对精度的影响.得出影响TWSTT精度的主要误差源为设备时延误差和路径传播时延误差,而由于卫星和地面站运动引起的误差相对较小,从而给... 详细信息

介绍了卫星双向时间比对(TWSTT)方法的发展过程及其基本原理,讨论了TWSTT的误差源,分析了各误差源对比对精度的影响.得出影响TWSTT精度的主要误差源为设备时延误差和路径传播时延误差,而由于卫星和地面站运动引起的误差相对较小,从而给出了实际应用时不同比对精度下需要考虑的误差源及对误差源的精度要求.

关键词：天体测量学卫星双向时间比对(TwSTT) 综述时间误差