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Acta Geologica Sinica(English Edition) 2000年第1期74卷 46-53页

作者： peng jim YI Haisheng XIA Wenjie Postdoctoral Researchers Flow Station of SW China Petroleum Institute Institute of Sedimentary Geology Chengdu University of Technology Chengdu 610059 Institute of Sedimentary Geology Chengdu University of Technology Chengdu 610059

: In the Hunan-Guizhou-Guangxi area there have developed very thick bedded siliceous rocks of the late Sinian. The rocks have a fairly pure composition, with an average content of siliceous minerals exceeding 95%. They are relatively rich in Fe and Mn, and poor in Al, Ti and Mg. The Fe/Ti, (Fe+Mn)/Ti, Al/(Al+Fe+Mn) and U/Th ratios and the Al-Fe-Mn and Fe-Mn-(Ni+Co+Cu)×10 triangle diagrams all show that they are hydrothermal sedimentary siliceous rocks. In the rocks the total amount of REEs is low, the δCe shows an obvious negative anomaly and the δEu a weak anomaly, and LREE>HREE, all indicating that they are products of hydrothermal processes. The δ30Si and δ18O values, as well as the formation temperature of the rocks all clearly show that the silica forming the rocks comes from hot water. Besides, analyses of the depositional environment of the rocks using the MnO/TiO2 ratio and the δCe and δ30Si values yield the same conclusion that they are formed in environments from continental marginal slopes of a bathyal environment to oceanic basins of a deep-sea environment.

关键词： siliceous rock hydrothermal sedimentary geochemistry environment Sinian the Hunan-Guizhou-Guangxi area

A Fault Diagnosis Method of Power Systems Based on an Improved Adaptive Fuzzy Spiking Neural P Systems and PSO Algorithms

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Chinese Journal of Electronics 2016年第2期25卷 320-327页

作者： WANG Jun peng Hong TU Min Prez-jimnez J. Mario SHI peng School of Electrical and Information Engineering Xihua University Neijiang Power Supply Company 5. Department of Computer Science and Artificial Intelligence University of Seville 6. School of Electrical and Electronic Engineeringthe University of Adelaide Sichuan Province Key Laboratory of Power Electronics Energy-saving Technologies and Equipment Center for Radio Administration and Technology Development Xihua University

A new fault diagnosis method based on improved Adaptive fuzzy spiking neural P systems(in short,AFSN P systems) and Particle swarm optimization(PSO)algorithm is presented to improve the efficiency and accuracy of diagnosis for power systems in this paper. AFSN P systems are a novel kind of computing models with parallel computing and learning ability. Based on our previous works, this paper focuses on AFSN P systems inference algorithms and learning algorithms and builds the fault diagnosis model using improved AFSN P systems for diagnosing effectively. The process of diagnosis based on AFSN P systems is expressed by matrix successfully to improve the rate of diagnosis eminently. Furthermore, particle swarm optimization algorithm is introduced into the learning algorithm of AFSN P systems, thus the convergence speed of diagnosis has a big progress. An example of 4-node system is given to verify the effectiveness of this method. Compared with the existing methods, this method has faster diagnosis speed, higher accuracy and strong ability to adapt to the grid topology changes.

关键词： Fault diagnosis Power systems Member Computing AFSN P systems Particle swarm optimization algorithm

Interfacial friction effects on sealing performances of elastomer packer

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Petroleum Science 2024年第3期21卷 2037-2047页

作者： peng-Cheng Wang Ming-Hui Chen jim Jenkinson Yong-Xin Song Li Sun Department of Mechanical Engineering University of HoustonHoustonTX77024USA Guren Nanomaterials Suzhou215127JiangsuChina Department of Marine Engineering Dalian Maritime UniversityDalian116026LiaoningChina

Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic *** practice sealing performances of such plugs are normally evaluated through pressure tests,and in numerical simulation studies,maximum contact stress,average contact stress and contact length data are used to determine sealing quality between a packer and *** previous studies,the impact of friction forces on sealing performance is often *** work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing *** first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac *** we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution,deformation,and contact stress after *** the demonstration of validity of FEA method,we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress,average contact stress,contact stress distribution,and maximum mises stress for an actual packer used in plug *** addition,we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial *** study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces.

关键词： Elastomer seal Friction Sealing performance Contact stress

Key-frame reference selection for non-feedback video communication

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 92-102页

作者： peng Qiang ZHANG Lei YANG Tian-wu CHEN jim X ZHU Ce School of Information Science & Technology Southwest Jiaotong University Chengdu 610031 China School of Information Technology & Engineering George Mason University VA 22030 USA School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798 Singapore

This article addresses the problem of reference picture optimization in video communication over error prone networks. A novel estimation model for transmission distortion is proposed. This model is capable of recursively estimating the overall end-to-end distortion caused by quantization, error propagation, and error concealment. Simulation results show that this model can accurately estimate channel distortion. Then, based on the distortion estimation model, a new non-feedback key-frame reference picture selection （KRPS） algorithm is developed. The optimum reference picture minimizes the transmission distortion under the rate-distortion optimization framework. Extensive experiment results demonstrate that the proposed KRPS algorithm substantially achieves more peak signal to noise ratio （PSNR） gain over traditional prediction, especially in low bit-rate transmission.

关键词： End-to-end distortion key-frame reference picture selection error resilience

Effect of the Resistance Exercise on Elementary School Students’Physical Fitness

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Journal of Science in Sport and Exercise 2019年第2期1卷 184-191页

作者： You Fu Ryan D.Burns Nora Constantino jim Fitzsimmons peng Zhang School of Community Health Sciences University of NevadaReno1664 N.Virginia StreetRenoNV 89557USA Department of Health Kinesiologyand RecreationCollege of HealthUniversity of UtahSalt Lake CityUT 84112USA Fitness and Recreational Sports University of NevadaReno1664 N.Virginia StreetRenoNV 89557USA Department of Physical Education Teacher Education East Stroudsburg University200 Prospect StreetEast StroudsburgPA 18301USA

Background Physical activity programs using components of resistance have the potential to improve health in school *** purpose of this study was to examine the effect of a school-based resistance exercise program on physical fitness in elementary school *** The sample was 256 children(mean age=8.3±2.5 years;119 girls)from kindergarten to 5th *** performed a 10-min resistance exercise 2-3 times in each school *** fitness outcomes were assessed using President’s Physical Fitness Challenge *** were collected at baseline and at a 6-month post-test time point.A 2×2 doubly MANOVA was employed to examine the effect of sex and *** The multivariate model was statistically significant with a main time effect(Wilks’λ=0.19,F=290.9,P<0.001).Follow-univariate tests found significant differences between time-points on flex arm hang(P=0.033),shuttle run(P<0.001),and 1-mile run/walk times(P<0.001).Conclusions A 6-month resistance exercise program improved upper body strength and cardiorespiratory endurance in elementary school aged *** use of resistance exercise intervention during school day can be effectively used to promote physical fitness and ultimately improve the health of children.

关键词： Resistance exercise Children Physical fitness

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视频传输差错掩盖技术研究现状与发展趋势

西南交通大学学报 2009年第4期44卷 473-483页

作者：彭强张蕾 Chen jim X. 西南交通大学信息科学与技术学院四川成都610031 乔治梅森大学计算机科学系

讨论了视频差错掩盖研究的发展过程和现状.介绍了常见的空域和时域差错掩盖算法,特别是基于边缘检测的空域自适应差错掩盖算法、基于运动向量外插的时域差错掩盖算法、多步多权值块变形差错掩盖算法以及基于失真度估计的SVC质量分级自... 详细信息

讨论了视频差错掩盖研究的发展过程和现状.介绍了常见的空域和时域差错掩盖算法,特别是基于边缘检测的空域自适应差错掩盖算法、基于运动向量外插的时域差错掩盖算法、多步多权值块变形差错掩盖算法以及基于失真度估计的SVC质量分级自适应差错掩盖算法.分析了这些算法在不同有损传输环境下的差错掩盖性能和适用环境.预测了差错掩盖技术可能的发展趋势.

关键词：视频编码视频传输差错控制差错掩盖

利用主动外观模型进行3D人脸的快速自动建模

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计算机辅助设计与图形学学报 2009年第5期21卷 668-673页

作者：范小九彭强 jim X Chen 西南交通大学信息科学与技术学院成都610031 Department of Computer Science George Mason University Fairfax VA 22030 4444 USA

针对传统方法存在的通用性不强、实时性较差和与视频传输系统不兼容等缺点,提出一种面向单幅任意姿态图像的3D人脸建模技术.首先将基于初始位置校正和模型实例选择的主动外观模型改进方法应用到人脸特征点的提取过程中;然后结合人脸结... 详细信息

针对传统方法存在的通用性不强、实时性较差和与视频传输系统不兼容等缺点,提出一种面向单幅任意姿态图像的3D人脸建模技术.首先将基于初始位置校正和模型实例选择的主动外观模型改进方法应用到人脸特征点的提取过程中;然后结合人脸结构特征和空间仿射变换调节CANDIDE-3线框模型,实现对应人脸的全局位置恢复和形状匹配.在此基础上,根据感兴趣区域的对称性对局部坐标进行微调,并构建真实感纹理.实验结果表明,该技术不受图像拍摄焦距等因素影响,单幅图像平均建模时间约为300ms.

关键词：主动外观模型位置恢复形状匹配线框模型 3D人脸建模

FTIR Characterization of Fluorine Doped Silicon Dioxide Thin Films Deposited by Plasma Enhanced Chemical Vapor Deposition

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Chinese Physics Letters 2000年第12期17卷 912-914页

作者： WANG peng-Fei DING Shi-Jin ZHANG Wei ZHANG jim-Yun WANG Ji-Tao WEI William Lee Department of Electronic Engineering Fudan UniversityShanghai 200433 Taiwan Semiconductor Manufacturing Co. HsinchuTaiwanChina

Fluorine doped silicon dioxide (SiOF) thin films have been prepared by plasma enhanced chemical vapor deposition. The Fourier transform infrared spectrometry (FTIR) spectra of SiOF films are deliberated to reveal the structure change of SiO_(2) and the mechanism of dielectric constant reduction after doping fluorine. When F is doped in SiO_(2) films, the Si-O stretching absorption peak will have a blue-shift due to increase of the partial charge of the O atom. The FTIR spectra indicate that some Si-OH components in the thin film can be removed after doping fluorine. These changes reduce the ionic and orientational polarization, and result in the reduction in dielectric constant of the film. According to Gaussian fitting, it is found that the Si-F2 bonds will appear in the SiOF film with increase of the fluorine content. The Si-F2 structures are liable to react with water, and cause the same increase of absorbed moisture in the film.

关键词： fluorine film dielectric

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一种改进的AAM人脸特征点快速定位方法

电子与信息学报 2009年第6期31卷 1354-1358页

作者：范小九彭强 jim X Chen 夏旭西南交通大学信息科学与技术学院成都610031 乔治梅森大学计算机科学系美国弗吉尼亚22030-4444

传统的AAM(Active Appearance Models)人脸特征定位改进方法通常关注于拟合效率上,没有具体考虑拟合初始位置和模型实例的特征,因此定位准确率和速度并不理想。该文提出了一种基于人脸特征检测和简单三维姿态估计的拟合初始位置改进和... 详细信息

传统的AAM(Active Appearance Models)人脸特征定位改进方法通常关注于拟合效率上,没有具体考虑拟合初始位置和模型实例的特征,因此定位准确率和速度并不理想。该文提出了一种基于人脸特征检测和简单三维姿态估计的拟合初始位置改进和模型实例选择方法。首先采用Adaboost算法对图像中人脸特征进行预检测,然后充分利用YCbCr色彩空间人脸肤色特性对无法检测或检测不完全的图像进行特征提取,最后根据特征区域计算鼻尖坐标和人脸偏转角,合理调整拟合中心位置和模型实例,并在拟合过程中引入ATLAS(Automatically Tuned Linear Algebra Software)线性代数软件包,实现矩阵优化。基于IMM人脸库的仿真实验表明,该方法与传统反向组合AAM相比,拟合准确率提高约43%,时间消耗降低约62%。

关键词：人脸识别 AAM 反向组合算法 Adaboost 三维姿态估计 ATLAS

SMIP-30,a potent and selective PPM1A inhibitor with potential to treat tuberculosis

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Acta Pharmaceutica Sinica B 2022年第12期12卷 4519-4521页

作者： Shujing Xu Xinyong Liu peng Zhan Department of Medicinal Chemistry Key Laboratory of Chemical BiologyMinistry of EducationSchool of Pharmaceutical SciencesShandong UniversityJi'nan 250012China

Recently,a collaborative research led by Weibo Yang and jim Sun1 published in Cell Chemical Biology identified a potent and selective small molecule inhibitor(SMIP-30)for human protein phosphatase Mg^(2+)/Mn^(2+)-dependent 1 A(PPM1A).They applied this chemical probe to determine the autophagy receptor p62 as a new substrate of PPM1A.

关键词： PPM1A Tuberculosis Drug discovery Compound library