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Mesozoic Thrust-Nappe and Extensional Structure Frameworks in the East Segment of Southeast Yangtze Block, Southeast China

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Journal of Earth Science 2020年第4期31卷 772-794页

作者： Xinqi Yu Ziwei Chen Jun Hu Yan Zeng Xiu Liu Yu He Zishen Wang Linghui Meng School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Chongqing Institute of Geology&Mineral Resources Chongqing 400042China

Multi-stage Mesozoic thrust-nappe and extensional structures are distributed in the east segment of the Southeast Yangtze Block situated in the junction region of Zhejiang-Jiangxi-Anhui provinces. The features and genetic mechanism of the deformations were analyzed after a detailed field observation of their distribution, geometry, and kinematics. In addition, the time sequences of the thrust and extensional structures were determined by combining the results of the comparative analysis with the chronological evidence of strata and magmatic rocks cut by a fault or formed after a fault according to field facts. This study identified three stages of the nappe structures and at least two stages of the extensional structures during the Mesozoic. The geotectonic setting of the nappe and extensional structures was considered to be related to the different geodynamics in the study area including the Early Mesozoic geological event, i.e., N-S compression, forming Lantian fault, etc.;the Late Mesozoic flat-slab subduction, forming Xiaoxi thrust fault and tectonic window;and the roll-back of the paleoPacific Plate, forming extensional structures like basin marginal fault;the last compression, forming Wucheng-Shenxian fault. These findings provide additional evidence for remodeling the tectonic and geodynamic evolution of Southeast China.

关键词： Mesozoic nappe structure extensional structure time sequence east segment of the Southeast Yangtze Block

Theory and Application of Natural-Based Wavelet Method

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Journal of Harbin Institute of Technology(New Series) 2019年第6期26卷 86-90页

作者： Yanhua Cao Mengcheng Chen Baogen Xu School of Science East China Jiaotong UniversityNanchang 330013China Institute of Architecture and Civil Engineering East China Jiaotong UniversityNanchang 330013China

Wavelet method is often used in analyzing trend and period of time sequence. When using wavelet method one serious problem is different chosen wavelet basis and scale would lead to different results. Sometimes, the results vary greatly. To overcome this problem and to improve the accuracy and efficiency, a new method denoted by Natural-based Wavelet Method is introduced and extended. It can be proved that the proposed method in fact is a special class of discrete wavelet. At first, two numerical examples are designed to show the capacity of the novel method. Second, this method is applied to a precipitation series. According to wavelet analysis and short-range precipitation prediction, this precipitation exists a faintly increasing trend. Through the analysis, the studied precipitation has two major periods: 11 and 41 years. The results validate that the Natural-based Wavelet Method used in application of multi-complicated observed data is suitable. It is easy to write the source code of the proposed method. When new information appears, new information can be easily added into the original sequence, this is another advantage of the proposed method.

关键词： natural-based wavelet method long-time precipitation sequence short-range precipitation time sequence

Characteristics and dynamics analysis of Populus euphratica populations in the middle reaches of Tarim River

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Journal of Arid Land 2010年第4期2卷 250-256页

作者： Wu, JunXia Zhang, XiMing Deng, ChaoZhou Liu, GuoJun Li, Hong Chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China Xinjiang Acad Forestry Urumqi 830000 Peoples R China

Populus euphratica Oliv. is widely distributed along the Tarim River. Maintaining stability of P. euphratica population is important to local development. This study explored the static life table, survivor- ship curves and four function curves (survival rate, cumulative mortality rate, mortality density, and hazard rate), and development index of P. euphratica population in the middle reaches of Tarim River. The results indicated that the age structure of P. euphratica population belonged to positive pyramidal type, which meant young age-class individuals occupied most populations. The number ofⅠ?Ⅱage classes accounted for 66.2% of whole population, and this indicated that there were abundant subsequent seedlings resources to support the growth of P. euphratica population in the middle reaches of Tarim River. The survivorship curve of P. euphratica belonged to the Deevey Ⅲ (concave-type) and the development index was 47.72%. Four function curves revealed that the individuals of P. euphratica sharply decreased at the initial stage and then leveled off at the late stage of survival curve. time sequence prediction models predicted that the number of midlife individuals would increase in future 10, 20, 30 years, and P. euphratica population grew steadily as a result of rich saplings.

关键词： Populus euphratica population static life table survivorship curve survival analysis development index time sequence

Flow-Guided Single Object Tracking Framework in UAV Aerial Video

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Flow-Guided Single Object Tracking Framework in UAV Aerial V...

第32届中国控制与决策会议

作者： Wenjun Zhu Xi Yu Jun Meng College of Electrical Engineering Zhejiang University Zhejiang University Robotics Institute

Tracking target in UAV aerial video is challenging for at least two reasons:（1） the target have small scale relative to the image which leads to have less feature information;and（2） compared to the traditional tracking,drones bring new challenges to the tracking methods,even the combination of several difficult scenarios.Notice that the most existing trackers only consider appearance feature of the current frame,and hardly benefit from information between time and motion sequence.In this paper,we address both issues inspired by time sequence and motion information.In particular,we proposed a network that unifies Siamese subnetwork and optical flow estimation in a framework.Given an aerial video,a CNN subnetwork is used for feature extraction and a flow subnetwork is used for flow estimation.Then according to target historical motion speed,EA module is used to reduce the redundant motion information by scale estimation and FA module is used for feature fusion.Finally each aggregated feature and template feature is fed into region proposal subnetwork.Extensive experiments are performed on popular aerial video datasets,and our proposed method achieves promising performance in comparison with state-of-the-art trackers.

关键词： Tracking Aerial video time sequence Motion information

Study of techniques of identifying the earthquake precursory anomalies in terms of mathematical modeling

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Acta Seismologica Sinica(English Edition) 2000年第6期13卷 646-655,717页

作者：严尊国钱家栋陈俊华李胜乐 Institute of Seismology China Seismological Bureau Wuhan China Center for Analysis and Prediction China Seismological Bureau Beijing China

This paper deals mainly with the key technique of identifying the anomalous signals without distortion, which might be the precursors associated with earthquakes, from the real time series of observations that would be usually the mixture of the anomalous signals, the normal background variations, some interference and noises. The key technique of 'un-biased estimation' is to construct an empirical time series and set up the criterion for identifying the anomalous variation on the bases of time series analysis. To the end of testing the method, a man-made time series including the normal variations and random interference as well as specific anomaly, has been constructed. And the test of picking up the anomaly has been conducted with the intuitive and effective way of identifying the anomalous signal from a complicated time series. Test results confirms that the techniques under discussion are effective and applicable, and the signals extracted from the analysis, could be clear and precise, and is almost similar to the known simulated anomalous signals in the experiments.

关键词： earthquake precursor time sequence anomalous identificat

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比例规则的优化算法

比例规则的优化算法

第十八届全国数据库学术会议

作者：卓明王丽珍周丽华谭旭云南大学计算机科学与工程系

1引言关联规则的挖掘是KDD和DM研究中的一个重要研究课题。目前,挖掘出的关联规则大体可划分为三种类型:

关键词： Knowledge discovery Ratio rules（RR） Classification time sequence Forecast

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基于时间序列的离散事件系统模型语义描述

基于时间序列的离散事件系统模型语义描述

2005年全国理论计算机科学学术年会

作者：李旭晖何炎祥彭智勇武汉大学软件工程国家重点实验室

1 引言离散事件系统(Discrete Event System,DEVS)模型是仿真的主要建模方法,也是系统仿真的基本模型,其主要功能是对实时系统建模并模拟其运行过程。建模过程是一个从问题域到计算域的映射过程,而映射即建立模型过程的正确性取决于对... 详细信息

1 引言离散事件系统(Discrete Event System,DEVS)模型是仿真的主要建模方法,也是系统仿真的基本模型,其主要功能是对实时系统建模并模拟其运行过程。建模过程是一个从问题域到计算域的映射过程,而映射即建立模型过程的正确性取决于对实际系统的认识是否全面。离散事件系统作为对实时系统外延的一种刻画,其能否反映实时系统的真实情况取决于其语义是否与所反映的实时系统一致。当前建模仿真理论中,研究者们的重点常集中

关键词： DEVS time sequence Semantic model

Double LSTM Structure for Network Traffic Flow Prediction

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国际计算机前沿大会会议论文集 2020年第1期 380-388页

作者： Lin Huang Diangang Wang Xiao Liu Yongning Zhuo Yong Zeng State Grid Sichuan Information and Communication Company Chengdu 610041China University of Electronic Science and Technology of China Chengdu 611731China The 10th Research Institute of China Electronics Technology Group Corporation Chengdu 610036China

The network traffic prediction is important for service quality control in computer network.The performance of the traditional prediction method significantly degrades for the burst short-term flow.In view of the problem,this paper proposes a double LSTMs structure,one of which acts as the main flow predictor,another as the detector of the time the burst flow starts at.The two LSTM units can exchange information about their internal states,and the predictor uses the detector’s information to improve the accuracy of the prediction.A training algorithm is developed specially to train the structure offline.To obtain the prediction online,a pulse series is used as a simulant of the burst event.A simulation experiment is designed to test performance of the predictor.The results of the experiment show that the prediction accuracy of the double LSTM structure is significantly improved,compared with the traditional single LSTM structure.

关键词： time sequence Long-short term memory neural network Traffic prediction Service quality control

维普期刊数据库评论

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基于时间序列相似性搜索的预测算法

基于时间序列相似性搜索的预测算法

第十九届全国数据库学术会议

作者：卓明王丽珍谭旭云南大学计算机科学与工程系

1引言随着数据库技术的飞速发展,大部分和时间相关的数据被贮存到了计算机中。时间序列知识发现对人类社会、科技和经济的发展具有重大意义。目前时间序列知识发现正成为知识发现的研究热点之一。尽管时间序列相似性搜索算法很多,

关键词： Knowledge discovery time sequence Similarity search Ratio rules（RR） Forecast