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Cramer-Rao bound of joint estimation of target location and velocity for coherent MIMO radar

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Journal of Systems Engineering and Electronics 2014年第4期25卷 566-572页

作者： peilin sun Jun Tang Shuang Wan Department of Electronic Engineering Tsinghua University

The optimal estimation performance of target parameters is studied. First, the general form of Cramer-Rao bound （CRB） for joint estimation of target location and velocity is derived for coherent multiple input multiple output （MIMO） radars. To gain some insight into the behavior of the CRB, the CRB with a set of given orthogonal waveforms is studied as a specific case. Second, a maximum likelihood （ML） estimation algorithm is proposed. The mean square error （MSE） of the ML estimation of target location and velocity is obtained by Monte Carlo simulation and it approaches CRB in the high signal-to-noise ratio （SNR） region.

关键词： Cramer-Rao bound (CRB) joint estimation coherentmultiple input multiple output (MIMO) radar.

Cramer-Rao bound and signal-to-noise ratio gain in distributed coherent aperture radar

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Journal of Systems Engineering and Electronics 2014年第2期25卷 217-225页

作者： peilin sun Jun Tang Xiaowei Tang Department of Electronic Engineering Tsinghua University

This paper studies the estimation performance of the coherent processing parameter （CPP）, including time delay differences and phase synchronization errors among different apertures of the distributed coherent aperture radar （DCAR）. Firstly, three architectures of signal processing in the DCAR are introduced. Secondly, the closed-form Cramer-Rao bound （CRB） of the CPP estimation is derived and compared. Then, the closed-form CRB is verified by numerical simulations. Finally, when the next generation radar works in a fully coherent mode, the closed-form signal-to-noise ratio （SNR） gain of the three architectures is presented.

关键词： Cramer-Rao bound (CRB) joint parameter estimation,distributed coherent aperture radar (DCAR).

筠连地区上二叠统乐平组层序地层及沉积相研究

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中国煤炭地质 2024年第1期36卷 1-11页

作者：王伟何金先张晓丽李聚豪黄正鑫孙沛琳宋佳遥中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221116 中国矿业大学资源与地球科学学院江苏徐州221116

四川南部筠连地区乐平组煤层气资源储量大,勘探程度总体较低,制约了煤及煤系气资源的开采。煤层聚集、砂岩储层展布受控于沉积相及层序地层格架控制。为探究研究区内煤层发育特征及煤层聚集的沉积控因,以钻井和岩心资料为基础,利用层序... 详细信息

四川南部筠连地区乐平组煤层气资源储量大,勘探程度总体较低,制约了煤及煤系气资源的开采。煤层聚集、砂岩储层展布受控于沉积相及层序地层格架控制。为探究研究区内煤层发育特征及煤层聚集的沉积控因,以钻井和岩心资料为基础,利用层序地层学原理,识别出区内乐平组发育的Ⅲ级层序界面并划分层序,构建层序地层格架;厘清研究区含煤地层名称;利用岩相标志及测井响应特征进行地层对比、单井沉积相划分及连井沉积相对比,明确沉积相在各层序内的发育特征。结果表明,研究区乐平组共存在四个层序界面,依据四个层序界面划分出三个Ⅲ级层序。以测井响应特征为主体,共识别出两类沉积相,五类沉积亚相及九类沉积微相。第一层序(SQ1)和第二层序(SQ2)主要发育河流相,第三层序(SQ3)发育潮坪相。在剖面上,整体表现为由河流相至潮坪相的演化特征;自西向东体现为河流-潮坪-潟湖相的演化趋势。

关键词：筠连地区层序地层沉积相上二叠统乐平组

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辐射诱变育种技术概述

黑龙江科学 2024年第16期15卷 16-19,24页

作者：斯琴图雅杨建鑫汤明威孙培琳张丹丹张子呈范庆丽黑龙江省原子能研究院哈尔滨150086 黑龙江大学哈尔滨150080

辐射诱变技术在种质创新、新品种培育方面具有独特优势。为加强人们对辐射诱变技术体系的了解,从辐射诱变源、诱变方式、诱变剂量、诱变材料及突变体筛选等方面对辐射诱变技术进行综述。不同诱变源的射线类别、射线穿透能力、电量、质... 详细信息

辐射诱变技术在种质创新、新品种培育方面具有独特优势。为加强人们对辐射诱变技术体系的了解,从辐射诱变源、诱变方式、诱变剂量、诱变材料及突变体筛选等方面对辐射诱变技术进行综述。不同诱变源的射线类别、射线穿透能力、电量、质量及辐射环境等条件各有差异,适宜诱变处理的材料也有所不同,只有结合相关因素,采用合适的突变体筛选方法才能达到理想的种质创新目的,为辐射诱变育种实践提供参考。

关键词：辐射诱变育种辐照方法突变体筛选

The gross α and β radioactivity levels of drinking water source in one oil industrial city in northeast China

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Radiation Medicine and Protection 2021年第2期2卷 61-66页

作者： Yan Shi Wa Gao Tuya Siqin Zhigang Li Jianwei Zhang Rongshu Guan Jinfeng Li peilin sun Hongtao Zhao Key Laboratory of Nuclear Technology Application Institute of Technical PhysicsHeilongjiang Academy of SciencesHarbin150086China

Objective:To investigate the grossαandβradioactivity levels of drinking water source in the city,the largest oil field production base in northeast China,in order to ensure the safety of drinking water and public ***:The water samples from three drinking water sources were collected and tested in the dry and wet season,*** grossαradioactivity was measured by standard curve method,grossβwas measured by thin sample ***:Totally 184 samples were collected from the three sampling areas in dry and wet season *** average values of grossαandβradioactivity levels in the drinking water source area were(0.24±0.09)and(0.30±0.17)Bq/L *** average activity concentration of grossαand grossβin the dry season was(0.23±0.09)and(0.29±0.18)Bq/L,*** grossαandβradioactivity levels gradually decreased from the intake to the end of the reservoir of drinking water source ***:The grossαandβradioactivity levels and distribution of drinking water source areas in this city were all lower than the drinking water limit issued by China and the reference level recommended by the World Health *** radioactivity of water body of the drinking water source was within the normal background level.

关键词： Water source Grossα Grossβ Radioactivity

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超滤膜技术在环境工程水处理中的实施分析

皮革制作与环保科技 2023年第4期4卷 16-18页

作者：孙培林菏泽市生态环境局成武县分局山东菏泽274200

超滤膜是利用特殊材料制备而成的微孔过滤装置,能够将悬浮颗粒物、胶体以及其他较大分子量的物质与水体分离,从而达到净化水质、改善环境的目的。本研究过程依托于某污水处理厂,在二沉池后设计了絮凝器、砂率器以及超滤膜组件,通过混凝... 详细信息

超滤膜是利用特殊材料制备而成的微孔过滤装置,能够将悬浮颗粒物、胶体以及其他较大分子量的物质与水体分离,从而达到净化水质、改善环境的目的。本研究过程依托于某污水处理厂,在二沉池后设计了絮凝器、砂率器以及超滤膜组件,通过混凝作用和砂率吸附作用进行污水预处理,再利用超滤膜系统进一步降低污水的浊度、COD、TP以及氨氮。结果显示:超滤膜技术能够显著降低水体的浊度,对COD也具有较好的处理效果,但难以去除TP和氨氮。

关键词：超滤膜技术水处理实施应用

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分布式相参雷达相参性能的两种监控算法

清华大学学报（自然科学版） 2014年第4期54卷 419-424页

作者：孙培林汤俊张宁清华大学电子工程系北京100084

分布式相参雷达(DCR)全相参模式相参性能的监控是一个重要问题。该文提出的两个监控算法均通过监控信噪比(SNR)增益来监控相参性能。SNR增益需要统计单路波形的SNR,难点也在于此。第一个监控算法针对单发射多接收天线(单发多收)体系,单... 详细信息

分布式相参雷达(DCR)全相参模式相参性能的监控是一个重要问题。该文提出的两个监控算法均通过监控信噪比(SNR)增益来监控相参性能。SNR增益需要统计单路波形的SNR,难点也在于此。第一个监控算法针对单发射多接收天线(单发多收)体系,单路波形可以从单个接收天线直接获得,进而统计SNR增益。第二个监控算法针对多发单/多收体系,由于全相参模式下各发射天线的基带波形相同,因此多个发射天线的波形在单个接收天线处是叠加在一起的,无法用匹配滤波方法分离出单路波形,该文提出了辅助天线技术从而可以监控SNR增益。数值仿真表明了两种监控算法的有效性。

关键词：分布式相参雷达(DCR) 相参性能监控辅助天线技术

基于层次分析法的海外油气项目投资环境风险定量评价

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国际石油经济 2023年第5期31卷 91-100页

作者：孙沛霖李祖欣黄飞中国石油勘探开发研究院项目评价研究所

百年未有之大变局的加速演变叠加全球疫情的影响,给中国海外油气项目带来诸多风险与挑战。中国油气企业需要进一步完善资源国投资环境的风险评估体系,在定性分析的基础上量化风险点,更加全面具体地掌握资源国的投资环境情况,为投资决策... 详细信息

百年未有之大变局的加速演变叠加全球疫情的影响,给中国海外油气项目带来诸多风险与挑战。中国油气企业需要进一步完善资源国投资环境的风险评估体系,在定性分析的基础上量化风险点,更加全面具体地掌握资源国的投资环境情况,为投资决策提供有效依据。通过对中国的国际油气合作项目进行调研,构建了海外油气项目风险评价指标体系,运用层次分析法对资源环境、法治环境、外交环境、政治环境、经济环境和社会环境这6项一级指标和27项二级指标进行权重计算,选取中亚-俄罗斯、中东、非洲、美洲、亚太这5大油气合作区的重点资源国作为样本进行定量评价,找出资源国投资环境中重要风险点,为海外油气项目投资提供决策依据。

关键词：海外油气项目投资环境层次分析法定量评价风险

DNA methylation clocks for estimating biological age in Chinese cohorts

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Protein & Cell 2024年第8期15卷 575-593页

作者： Zikai Zheng Jiaming Li Tianzi Liu Yanling Fan Qiao-Cheng Zhai Muzhao Xiong Qiao-Ran Wang Xiaoyan sun Qi-Wen Zheng Shanshan Che Beier jiang Quan Zheng Cui Wang Lixiao Liu Jiale Ping Si Wang Dan-Dan Gao Jinlin Ye Kuan Yang Yuesheng Zuo Shuai Ma Yun-GuiYang Jig Qu Feng Zhang peilin Jia Guang-Hui Liu Weiqi Zhang CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of Computational Biology Shanghai Institute of Nutrition and HealthChinese Academy of SciencesShanghai 200031China Division of Orthopaedics Quzhou Affliated Hospital of Wenzhou Medical UniversityQuzhou 324000China The Joint Innovation Center for Engineering in Medicine Quzhou Affliated Hospital of Wenzhou Medical UniversityQuzhou 324000China Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric DisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China Aging Translational Medicine Center Intemational Center for Aging and CancerXuanwu HospitalCapital Medical UniversityBeijing 100053China Aging Biomarker Consortium Beijing 100101China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Organ Regeneration and Reconstruction Institute of ZoologyChinese Academy of SciencesBeijing 100101China nstitute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China National Genomics Data Center Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China

Epigenetic clocks are accurate predictors of human chronological age based on the analysis of DNA methylation(DNAm)at specific CpG ***,a systematic comparison between DNA methylation data and other omics datasets has not yet been ***,available DNAm age predictors are based on datasets with limited ethnic *** address these knowledge gaps,we generated and analyzed DNA methylation datasets from two independent Chinese cohorts,revealing age-related DNAm ***,a DNA methylation aging clock(iCAS-DNAmAge)and a group of DNAm-based multi-modal clocks for Chinese individuals were developed,with most of them demonstrating strong predictive capabilities for chronological *** clocks were further employed to predict factors influencing aging *** DNAm aging clock,derived from multi-modal aging features(compositeAge-DNAmAge),exhibited a close association with multi-omics changes,lifestyles,and disease status,underscoring its robust potential for precise biological age *** findings offer novel insights into the regulatory mechanism of age-related DNAm changes and extend the application of the DNAm clock for measuring biological age and aging pace,providing the basis for evaluating aging intervention strategies.

关键词： DNA methylation aging clock aging age prediction