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Acta Geologica Sinica(English Edition) 2006年第4期80卷 514-521页

作者： HOU Zengqian CHEN Wen lu jiren Institute of Geology Chinese Academy of Geological Science Beijing 100037 Institute of Mineral Resources Chinese Academy of Geological Science Beijing 100037

A suite of continental flood basalts sampled over a vast exposure and stratigraphic thickness in the Emeishan large igneous province （LIP）, SW China was investigated for laser microprobe ^40Ar/^39Ar dating. There are two ^40Ar/^39Ar age groups for these basalts, corresponding to 259-246 Ma and 177-137 Ma, respectively. A well-defined isochron gives an eruption age of huge quantities of mafic magmas at 258.9±3.4 Ma, which is identical to previous dating and paleontological data. Much younger ^40Ar/^39Ar ages for some basalts with Iow-greenschist metamorphic facies probably recorded a late thermo-tectonic event caused by collision between the Yangtze and Qiangtang continental blocks during the Mesozoic, which resulted in the reset of argon isotope system. The ^40Ar/^39Ar age data, we present here, combined with previous dating and paleontological data, suggest relatively short duration （about 3 Ma） of mafic volcanism, which have important implication on mantle plume genesis of the Emeishan continental flood basalts in the LIP.

关键词： laser microprobe ^40Ar/^39Ar age continental flood basalts Emeishan large igneous province

Polygenetic Mineralization of the Early ProterozoicTongkuangyu Metaporphyry Copper Deposit inthe Zhongtiao Mountains,Shanxi Province

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Acta Geologica Sinica(English Edition) 1998年第2期72卷 154-168,243页

作者： CHEN Wenming ZHANG Chengxin lu jiren DANG Zefa LI Shuping CUI Wenbin NING Yuan Institute of Mineral Deposits Chinese Academy of Geological Sciences26 BaiwanzhangBeijing 100037 Shanxi Institute of Geology and Mineral Resources TaiyuanShanxi 030006

Abstract: The Tongkuangyu metaporphyry copper deposit formed in the Early Proterozoic is tectonically located in the northern part of the Zhongtiao Λ-type palaeorift depression, on the southern margin of the North China platform. The genesis of the deposit has long been a hot subject of research of geologists working on mineral deposits. By means of the protolith reconstruction and fluid inclusion and isotope studies of host rocks of the deposits, the authors hold that this deposit is the product of combined exogenic, endogenic and metamorphic processes. Its formation mainly involved the following four stages: (1) the stage of formation of Mg- and Fe-rich tuffaceous variegated cupriferous sand-shale and K-rich biomodal volcanic rocks; (2) the early stage of formation of the metaporphyry copper deposit; (3) the stage of formation of the metaporphyry copper deposit; and (4) the stage of reworking of the metaporphyry copper deposit.

关键词： Tongkuangyu metaporphyry copper deposit polygenetic mineralization

Target recognition algorithm for passive sonar system with high generalization ability

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Chinese Journal of Acoustics 1998年第2期17卷 179-188页

作者： GAO Xiang lu jiren (Department of Radio Engzneering, Southeast University Nanjing 210018)

A new algorithm based on a Supervised Self-Organizing neural network for the pas sive sonar target recognition was proposed. Because of the incompleteness of the passive sonar exemplar set, the algorithm introduced a Multi-Activation-function structure and Supervised Self-Organizing competitive learning algorithm into the classic feed-forward neural networks,and obviously improved the generalization ability in target recognition. Besides, it can effi ciently reduce the learning time and avoid the local optimum. The recognition experiments of realistic passive sonar signals show that this new algorithm has good generalization ability and high recognition rate

关键词： Target recognition algorithm for passive sonar system with high generalization ability high IEEE

Extraction and application of the low dimensional dynamical component from underwater acoustic target radiating noise

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Chinese Journal of Acoustics 2001年第4期20卷 319-326页

作者： LIANG Juan, lu jiren (Depertment of Radio Engineering, Southeast University Nanjing 210096) Department of Radio Engineering Southeast University Nanjing210096

Signal processing in phase space based on nonlinear dynamics theory is a new method for underwater acoustic signal processing. One key problem when analyzing actual acoustic signal in phase space is how to reduce the noise and lower the embedding dimen- sion. In this paper, local-geometric-projection method is applied to obtain fow dimensional element from various target radiating noise and the derived phase portraits show obviously low dimensional attractors. Furthermore, attractor dimension and cross prediction error are used for classification. It concludes that combining these features representing the geometric and dynamical properties respectively shows effects in target classification.

关键词： Extraction and application of the low dimensional dynamical component from underwater acoustic target radiating noise

Fractal Brownian motion model of ship radiated noise

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Chinese Journal of Acoustics 1999年第1期18卷 10-18页

作者： CHEN Xiangdong GAO Xiang lu jiren(Dept. of Radio Eng., Southeast University Nanjing 210018)

On the basis of the fractal geometry, a nactional Brownian Motion (FBM) model for the noise radiated by ship was established, under which its fractal dimension has been obtained and the Fractal Characteristic Vector (FCV) was constructed in the fractional Brownian random field (FBRF). By using of them, a new technique of the characteristic analysis for target recognition in the underwater acoustics was presented. A comparative experiment for classification shows us that the FCV can be used as essential quantity by which some defects existing in the methods to do the characteristic extraction elsewhere can be remedied.

关键词： Fractal Brownian motion model of ship radiated noise ITI

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一种新的混沌同步及保密通信方式

通信学报 1998年第9期19卷 47-53页

作者：纪飚陆佶人东南大学无线电工程系

本文提出一种新的混沌同步及保密通信方式。在发送端，将信息信号与混沌载波的和经取模运算后再嵌入混沌动力系统的迭代之中以实现调制；在接收端，用一个相应的非动力学系统从接收信号中提取混沌载波并进而恢复信息信号。研究表明，该... 详细信息

本文提出一种新的混沌同步及保密通信方式。在发送端，将信息信号与混沌载波的和经取模运算后再嵌入混沌动力系统的迭代之中以实现调制；在接收端，用一个相应的非动力学系统从接收信号中提取混沌载波并进而恢复信息信号。研究表明，该混沌同步方式具有较强的抗干扰能力并且实现容易；该保密通信系统保密性能良好。

关键词：混沌离散动力系统同步保密通信

Local-linear-prediction analysis for underwater acoustic target radiated noise

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Chinese Journal of Acoustics 2002年第4期21卷 372-378页

作者： LIANG Juan lu jiren(Department of Radio Engineering., Southeast University Nanjing 210096) Received May 9, 2001 Revised Sept. 4, 2001 Department of Radio Engineering. Southeast University Nanjing210096

Local-linear-prediction in phase space is performed for the underwater acoustic target radiated noise. Relation curve of average prediction error versus neighboring points' number is calculated. The result is used in judging the nonlinearity of radiated noise time series, and obtaining the appropriate form and coefficients of predicting model. The line and continuous spectral component are predicted respectively. Choice of some model parameters minimizing the prediction error is also discussed.

关键词： Local-linear-prediction analysis for underwater acoustic target radiated noise line

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基于混沌参数调制的数字通信方式

通信学报 1999年第11期20卷 50-54页

作者：纪飚陆佶人东南大学无线电工程系南京210096

提出一种基于混沌参数调制的数字通信方式。即将一个由非线性映射所产生的混沌序列作为载波，将待发送的有用信号（数字信号）作为调制信号，对非线性映射的某一参数在其混沌区域内进行调制。在接收端，利用混沌序列的发生规则从接收信... 详细信息

提出一种基于混沌参数调制的数字通信方式。即将一个由非线性映射所产生的混沌序列作为载波，将待发送的有用信号（数字信号）作为调制信号，对非线性映射的某一参数在其混沌区域内进行调制。在接收端，利用混沌序列的发生规则从接收信号中提取混沌载波，并经过简单的信号处理运算恢复出原来的有用信号。分析和计算机模拟表明，本文所提出的这种混沌通信系统具有一定的保密性且实现方便。

关键词：混沌调制混沌通信保密通信数字通信

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船载柔性阵基元坐标实时获取技术研究

数据采集与处理 2010年第1期25卷 86-92页

作者：安良陈励军陆佶人凌斌东南大学信息科学与工程学院南京210096

为了解决船载柔性阵被动定位系统中基元位置不确定的问题,提出了实时获取柔性阵基元坐标的技术方案。利用辅助声源发射直接扩频的DPSK(Differential phase shift keying)信号,根据广义互相关法估计DPSK信号到达各基元的时延,进而计算各... 详细信息

为了解决船载柔性阵被动定位系统中基元位置不确定的问题,提出了实时获取柔性阵基元坐标的技术方案。利用辅助声源发射直接扩频的DPSK(Differential phase shift keying)信号,根据广义互相关法估计DPSK信号到达各基元的时延,进而计算各基元的位置坐标。利用水池试验和湖上试验对该方法进行了实验验证,用实时获取的阵元坐标计算得到的目标距离与GPS测量的结果相一致。理论与实验分析的结果表明,本文的方法能够准确地实时获取柔性阵基元的坐标信息。

关键词：被动定位柔性阵基元坐标直接扩频信号广义互相关

A study on continuous Chinese speech recognition based on stochastic trajectory models

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Chinese Journal of Acoustics 1997年第4期16卷 350-355页

作者： MA Xiaohui(Department of Radio Engineering Southeast University Nanjing 210096)GONG Yifan(CRIN/CNRS France)FU Yuqing lu jiren(Department of Radio Engineering Southeast University Nanjing 210096)

After pointed the unreasonableness of the three basic assumptions contained in HMM, we introduce the theory and the advantage of Stochastic najectory Models (STMs) that possibly resolve these problems caused by HMM assumptions. In STM, the acoustic observations of an acoustic unit are represented as clusters of trajectories in a parameter *** trajectories are modelled by mixture of probability density functions of random sequence of states. After analyzing the characteristics of Chinese speech, the acoustic units for continuous Chinese speech recognition based on STM are discussed and phone-like units are suggested. The performance of continuous Chinese speech recognition based on STM is studied on VINICS system. The experimental results prove the efficiency of STM and the consistency of phone-like units.

关键词： IEEE ACTA A study on continuous Chinese speech recognition based on stochastic trajectory models