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Chinese Physics B 2021年第5期30卷 312-319页

作者： Ke Wang Xiaopeng Yan† Ze Li Xinhong Hao honghai yu Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China

Conventional parameter estimation methods for pseudo-random binary code-linear frequency modulation(PRBC-LFM)signals require prior knowledge,are computationally complex,and exhibit poor performance at low signal-to-noise ratios(SNRs).To overcome these problems,a blind parameter estimation method based on a Duffing oscillator array is proposed.A new relationship formula among the state of the Duffing oscillator,the pseudo-random sequence of the PRBC-LFM signal,and the frequency difference between the PRBC-LFM signal and the periodic driving force signal of the Duffing oscillator is derived,providing the theoretical basis for blind parameter *** based on amplitude method,short-time Fourier transform method,and power spectrum entropy method are used to binarize the output of the Duffing oscillator array,and their performance is *** pseudo-random sequence is estimated using Duffing oscillator array synchronization,and the carrier frequency parameters are obtained by the relational expressions and characteristics of the difference *** results show that this blind estimation method overcomes limitations in prior knowledge and maintains good parameter estimation performance up to an SNR of-35 dB.

关键词： Duffing oscillator pseudo-random binary code-linear frequency modulation(PRBC-LFM)signal blind parameter estimation low signal-to-noise ratio(SNR)

Characteristics of spatial magnetic torque of an intestine capsule micro robot with a variable diameter

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Science China(Technological Sciences) 2009年第7期52卷 2079-2086页

作者： ZHANG YongShun yuE Ming GUO DongMing WANG DianLong yu honghai JIANG Shengyuan ZHANG XueWen Key Laboratory for Precision&Non-traditional Machining of Ministry of Education Dalian University of TechnologyDalian 116024China School of Automotive Engineering Dalian University of TechnologyDalian 116024China Mechanical Engineering School Beihua UniversityJilin 132021China

A drive and control method is put forward for a variable diameter capsule micro robot to screw forward in intestine using magnetic coupling between an inner actuator inside the robot and the rotational magnetic field generated by a rotating outer actuator. The structures of the outer and inner actuators are magnet cylinders with multiple magnetic poles in tegular shape alternating with dissimilar radial magnetization. An universal mathematical model of magnetic torque at eccentric state is established based on the equivalent magnetic charge method, and the characteristics of magnetic torque with respect to structural parameters of actuators are theoretically studied. Experiments show that the driving method features advantages such as powerful magnetic torque, high safety, reliability, etc. The driving ability of the variable diameter capsule micro robot is greatly improved by its automatic radial clearance compensation. The magnetic drive system has a promising prospect of medical applications in intestine.

关键词： variable diameter capsule robot, Radial offset distance Magnetic torque, Equivalent magnetic charge method

Dynamic characteristics of an intestine capsule robot with variable diameter

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Chinese Science Bulletin 2010年第17期55卷 1813-1821页

作者： ZHANG YongShun JIANG Shengyuan ZHANG XueWen yu honghai WANG DianLong GUO DongMing Key Laboratory for Precision & Non-traditional Machining of Ministry of Education of China Dalian University of Technology Dalian 116023 China Mechanical Engineering School Beihua University Jilin 132021 China

This paper proposes an intestine capsule robot with variable diameter. It is driven by external rotating magnetic field and has the function of automatic radial clearance compensation. An external magnetic field generating device and a capsule robot with variable diameter are developed. Radial dynamic balance equation and kinematics equation of the capsule robot traveling inside flexible elasto-wall environment are established, and dynamic characteristics of the capsule robot inside flexible elasto-wall pipe and rigid wall pipe environments are analyzed and compared. Simulations and experiment results show that its dynamic characteristics in both pipes are almost the same. Under the action of radial clearance compensation, fluid dynamic pressure around outer surface of the capsule robot and its propulsion, as well as its adaptability to diameter change range, are significantly improved. Its propulsion and moving speed are controlled by adjusting rotating angular speed of the rotating magnetic field. This innovative capsule robot with radial clearance compensation has a promising prospect for inside intricate gastrointestinal (GI) tract in non-invasive therapy applications.

关键词：动态特性机器人变直径胶囊胃肠动力平衡方程径向间隙旋转磁场

Does investor communication improve corporate social responsibility?A machine learning-based textual analysis

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China Journal of Accounting Research 2024年第3期17卷 25-49页

作者： Siyu Fan Dongmin Kong Jie Lu honghai yu School of Management and Engineering Nanjing UniversityNanjingChina Department of Accountancy City University of Hong KongHong KongChina School of Economics Huazhong University of Science and TechnologyWuhanChina

In this study,we take a machine learning-based approach to measure institutional investor attention to corporate social responsibility(CSR)issues when communicating with firms during site *** find that institutional investors can effectively enhance CSR performance through CSR-related communica*** effect remains robust to various checks and is more pronounced for non-state-owned enterprises and firms with lower levels of institutional ownership and in periods following the issuance of Green Investment Guide*** also identify information asymmetry and financing constraints as the two mechanisms underlying this ***,our findings highlight the importance of private interactions between management and institutional investors in promoting CSR.

关键词： Corporate Social Responsibility Institutional Investors Site Visits Textual Analysis

The study on a new technology of waterway information system

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Acta Oceanologica Sinica 2009年第5期28卷 112-127页

作者： HUANG yu WU honghai HE Ye YAO Shengchu College of Civil Engineering and Architecture Zhejiang University Hangzhou 310058 China College of Science Zhejiang University Hangzhou 310058 China

It is a lot limitations to survey and design waterway by the CAD technique, due to timely variation of hydrology and ecology in the complicated estuary area, such as Changjing River estuary. In this paper, the advantages of GIS technique is applied to manage and process the multi kind , multi scale and multi time hydrographic parameters, including water depth, current velocity, tidal, waves, wind speed, temperature and salinity etc., also to deal with different projection, different scale charts. Meanwhile, in the paper, combination techniques of GIS and CAD has been developed for unification of the charts for efficient management, two-way automatic carts conversion between GIS and CAD, automatic cutting and assemble of a number of Charts, flight path of the projection of spatial data and coordinate transformation. This new technique has been applied to survey and design waterway of Changing River estuary. The result shows that the combination technology of GIS and CAD has application potentiality in the waterway survey and design.

关键词： GIS CAD waterway information system

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终极控制权、法制环境与上市公司现金持有

南方经济 2012年第11期41卷 55-66页

作者：俞红海南京大学工程管理学院

中国上市公司高额现金持有现象十分突出,本文基于控股股东侵占与中小投资者法律保护视角对这一问题进行了系统研究。通过利用2004-2008年上市公司数据,采用面板数据方法中的固定效应模型,本文研究表明:代表控股股东侵占的控股股东控制... 详细信息

中国上市公司高额现金持有现象十分突出,本文基于控股股东侵占与中小投资者法律保护视角对这一问题进行了系统研究。通过利用2004-2008年上市公司数据,采用面板数据方法中的固定效应模型,本文研究表明:代表控股股东侵占的控股股东控制权与现金流权分离度越大,公司现金持有比例越高,而在投资者法律保护好的情况下,分离度对现金持有比例的影响减小。进一步研究表明,两权分离度对现金持有的市场价值产生显著为负的影响,投资者法律保护则产生正向影响。本文的研究从公司治理角度揭示了中国企业高额现金持有现象产生机制及市场影响,并从现金持有角度进一步揭示了控股股东侵占行为。

关键词：现金持有控股股东侵占投资者法律保护

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脉冲多普勒引信抗周期调制干扰性能研究

北京航空航天大学学报 2018年第5期44卷 1018-1025页

作者：刘少坤闫晓鹏栗苹于洪海北京理工大学机电动态控制重点实验室北京100081

为了定量分析和表征脉冲多普勒(PD)引信的抗干扰性能,以处理增益为参量,研究了周期调制干扰信号对脉冲多普勒引信的作用效果,明确了脉冲多普勒引信抗干扰性能的影响因素。理论推导了典型周期调制干扰信号作用下,脉冲多普勒引信从接收回... 详细信息

为了定量分析和表征脉冲多普勒(PD)引信的抗干扰性能,以处理增益为参量,研究了周期调制干扰信号对脉冲多普勒引信的作用效果,明确了脉冲多普勒引信抗干扰性能的影响因素。理论推导了典型周期调制干扰信号作用下,脉冲多普勒引信从接收回波到相关检测这一过程的处理增益,获得了脉冲多普勒引信抗干扰性能与影响因素之间的量化关系,既为脉冲多普勒引信抗干扰设计提供了理论依据,又为脉冲多普勒引信抗干扰性能评估提供了技术支撑。理论推导、仿真和实测结果表明:脉冲多普勒引信抗周期性调幅干扰性能弱于抗周期性调频干扰性能;抗周期调制干扰性能主要受距离门脉冲宽度、多普勒滤波器类型和带宽影响。

关键词：脉冲多普勒(PD)引信抗干扰性能处理增益周期调幅干扰周期调频干扰

地源热泵垂直埋管换热器地下热阻及管长的分析

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制冷与空调（四川） 2007年第4期21卷 48-53页

作者：余红海东华大学环境学院上海201620

讨论了地源热泵垂直埋管换热器传热过程及其数学模型,引入热阻的概念,将埋管换热器管内流体与土壤的传热过程分为钻孔内和钻孔外两部分。阐述了利用传统的线源和柱源理论求解钻孔外热阻的方法,并结合实例对影响埋管换热器管长的因素进... 详细信息

讨论了地源热泵垂直埋管换热器传热过程及其数学模型,引入热阻的概念,将埋管换热器管内流体与土壤的传热过程分为钻孔内和钻孔外两部分。阐述了利用传统的线源和柱源理论求解钻孔外热阻的方法,并结合实例对影响埋管换热器管长的因素进行了对比分析,可供工程设计计算使用。

关键词：地源热泵垂直埋管换热器线源理论柱源理论热阻管长

某省立医院中央空调系统设计方案与运行数据分析

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制冷与空调 2021年第5期21卷 61-66页

作者：余红海安徽省建筑设计研究总院股份有限公司

以某省立医院门诊医技、住院楼为例,介绍了其中央空调冷热源配置、冷热负荷、水系统、风系统、净化区域的设计方案,收集了制冷、供暖主要空调季节11个月的费用账单,并进行了整理,总结了中央空调系统年度能源消费及单位建筑实际能耗,分... 详细信息

以某省立医院门诊医技、住院楼为例,介绍了其中央空调冷热源配置、冷热负荷、水系统、风系统、净化区域的设计方案,收集了制冷、供暖主要空调季节11个月的费用账单,并进行了整理,总结了中央空调系统年度能源消费及单位建筑实际能耗,分析了蒸汽凝结水热回收系统的经济与环境效益,对于医院建筑,具有一定的代表性及可借鉴性。

关键词：医院中央空调设计方案运行数据能源消费

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火电厂湿排灰渣在工程中的应用

电力标准化与计量 2005年第3期14卷 31-33页

作者：虞红海宁波港建设总公司宁波315800

本文采用激发剂激发湿排灰渣的活性,并根据工程应用的特点设计了湿排灰净浆、砂浆和混凝土。经激发的湿排灰材料,其性能不仅可以满足各种工程的地基处理,也能够用于许多中等标号要求的混凝土辅助工程,为大量消耗火电厂的废弃物,并为工... 详细信息

本文采用激发剂激发湿排灰渣的活性,并根据工程应用的特点设计了湿排灰净浆、砂浆和混凝土。经激发的湿排灰材料,其性能不仅可以满足各种工程的地基处理,也能够用于许多中等标号要求的混凝土辅助工程,为大量消耗火电厂的废弃物,并为工程提供一种廉价、(低等级要求中的)高性能材料开拓了新的思路。

关键词：湿排灰渣活性激发基础处理工程应用火电厂灰渣高性能材料激发剂地基处理辅助工程