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工况参数对双列角接触轮毂轴承单元温度分布的影响

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轴承 2025年第1期 82-87页

作者：马亚飞董艳方邱明何恺陈非凡河南科技大学机电工程学院河南洛阳471003 机械装备先进制造河南省协同创新中心河南洛阳471003

为研究影响双列角接触轮毂轴承单元温度分布的关键因素,基于光纤传感的波分复用技术实现轮毂轴承单元外圈12个测温点的分布式测温试验,并将试验数据与灰色关联度模型结合,对影响轮毂轴承单元温度分布的因素进行分析排序。试验结果表明:... 详细信息

为研究影响双列角接触轮毂轴承单元温度分布的关键因素,基于光纤传感的波分复用技术实现轮毂轴承单元外圈12个测温点的分布式测温试验,并将试验数据与灰色关联度模型结合,对影响轮毂轴承单元温度分布的因素进行分析排序。试验结果表明:各列各测点温度出现明显的分化现象,右列温升高于左列且右列测点温度离散性更大;联合载荷工况下,工况参数对轴承左列平均温升、右列平均温升、平均温升、轴向温差、左列周向温差、右列周向温差的影响程度从大到小排序均为转速、轴向力、径向力。

关键词：滚动轴承轮毂轴承单元灰色关联分析温升试验温度载荷转速

On the Process of Peasant Workers' Transformation to Urban Residents

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Chinese Journal of Population,Resources and Environment 2008年第1期6卷 63-71页

作者： Liu Chuanjiang dong yanfang Wang Jing Center for Economic Development Research Wuhan University Wuhan Hubei 430072 China Center for Population Resource and Environment Economy Research Wuhan University Wuhan Hubei 430072 China

The unique two-stage "Chinese path" of China’s ru-ral-urban migration, which cannot be fully explained by classical theories of economic development, makes us to give peasant workers’ transformation to urban residents a top priority. On the basis of fully explaining peasant workers’ transformation to urban residents, a method for measuring its process has been advanced and then confirmed with the data of March in 2005 from surveys to peasant workers in Wuhan. Finally, the suggestions of acceler-ating peasant workers’ transformation to urban residents to pro-mote the construction of a harmonious society have been drawn from the analysis.

关键词： rural-urban migration peasant workers' transformation to urban residents process of peasant workers' transformation to urban residents

Performance Analysis of Intelligent CR-NOMA Model for Industrial IoT Communications

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Computer Modeling in Engineering & Sciences 2020年第10期125卷 239-257页

作者： Yinghua Zhang Jian Liu Yunfeng Peng yanfang dong Changming Zhao School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Dawning Information Industry Co. Ltd.Beijing100193China School of Computer Science Chengdu University of Information TechnologyChengdu610225China

Aiming for ultra-reliable low-latency wireless communications required in industrial internet of things(IIoT)applications,this paper studies a simple cognitive radio non-orthogonal multiple access(CR-NOMA)downlink *** system consists of two secondary users(SUs)dynamically interfered by the primary user(PU),and its performance is characterized by the outage probability of the SU *** outage probability is calculated under two conditions where,a)the transmission of PU starts after the channel state information(CSI)is acquired,so the base station(BS)is oblivious of the interference,and b)when the BS is aware of the PU interference,and the NOMA transmission is adapted to the more comprehensive knowledge of the signal to interference plus noise ratio(SINR).These results are verified by simulations,and their good agreement suggests our calculations can be used to reduce the complexity of future *** find the outage probability is reduced when the SUs move further away from the primary transmitter or when the signal from PU is less powerful,and the BS always has better performance when it is aware of the *** findings thus emphasize the importance of monitoring the channel quality and realtime feedback to optimize the performance of CR-NOMA system.

关键词： Industrial internet of things(IIoT) non-orthogonal multiple access(NOMA) quality of service(QoS) successive interference cancellation(SIC)

Post-earthquake building damage assessment in Yushu using airborne SAR imagery

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Earthquake Science 2011年第5期24卷 463-473页

作者： Dingjian Jin Xiaoqing Wang Aixia Dou yanfang dong Institute of Earthquake Science China Earthquake Administration Beijing 100036 China

The synthetic aperture radar （SAR） plays an important role in earthquake emergency response because of its all-time and all-weather imaging capabilities. On April 14, 2010, an Ms7.1 earthquake occurred in Yushu county, Qinghai province of China, causing a lot of buildings collapsed. In this paper, the building damage in Yushu city due to the earthquake was assessed quantitatively using high-resolution X-band airborne SAR image. The features of the buildings with different damage levels （collapsed, partial collapsed, non-collapsed） in the SAR image were analyzed first. Based on these building features, we interpreted the individual building damage in Yushu city block by block and got the numbers of the collapsed, partial collapsed and non-collapsed buildings separately for each block, referring to pre-earthquake QuickBird image when necessary. Let the damage index of individual collapsed, partial collapsed, non-collapsed building be 1, 0.5, 0 respectively, the remote sensing damage index of each block was then calculated through remote sensing damage index equation. Finally, the preliminary quantitative relationship between the remote sensing damage index interpreted from the SAR image and that interpreted from the optical image was built up. It can be concluded that a desirable damage assessment result can be derived from high-resolution airborne SAR imagery.

关键词： SAR remote sensing Yushu earthquake damage assessment seismic damage index manual interpretation

Performance Analysis of Relay Based NOMA Cooperative Transmission under Cognitive Radio Network

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Computers, Materials & Continua 2020年第4期63卷 197-212页

作者： Yinghua Zhang Jian Liu Yunfeng Peng yanfang dong Guozhong Sun Hao Huang Changming Zhao School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Dawning Information Industry(Beijing)Co. Ltd.Beijing100083China Higon Austin R&D Center AustinTX 78746USA School of Computer Science Chengdu University of Information TechnologyChengdu610225China College of Computer Science Sichuan UniversityChengdu610041China

This paper proposes a hybrid spectrum accessing mechanism by using NOMA-based cooperative transmission and beam-forming *** this mechanism,the secondary user employs spectrum-sensing technology to detect the existence of the primary *** the primary user does not exist,the secondary source user directly transmits data to the destination *** the primary user exists,the secondary source user finds the optimal relay according to certain selection principle before transmitting data to the destination user through the chosen relay *** the signal receiving stage,the secondary user takes use of beam-forming technology to receive the signal from both the secondary source and the secondary relay *** the interference from the primary user is cancelled out in the ***,the outage probability for secondary user in the proposed mechanism is theoretically ***,the simulation results show that compared with the traditional mechanism,the proposed system model can not only guarantee the continuity of secondary transmission,but also significantly reduce the outage probability of secondary transmission.

关键词： Relay selection outage probability NOMA QoS signal-to-interference-plus-noise rate(SINR) beam-forming

Coseismic deformation of the 2021 M_(W)7.4 Maduo earthquake from joint inversion of InSAR, GPS, and teleseismic data

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Earthquake Science 2021年第5期34卷 436-446页

作者： Chaoya Liu Ling Bai Shunying Hong yanfang dong Yong Jiang Hongru Li Huili Zhan Zhiwen Chen Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China

The M_(W)7.4 Maduo earthquake occurred on 22 May 2021 at 02:04 CST with a large-expansion surface *** earthquake was located in the Bayan Har block at the eastern Tibetan Plateau,where eight earthquakes of M_(S)>7.0 have occurred in the past 25 ***,we combined interferometric synthetic aperture radar,GPS,and teleseismic data to study the coseismic slip distribution,fault geometry,and dynamic source rupture process of the Maduo *** found that the overall coseismic deformation field of the Maduo earthquake is distributed in the NWW-SEE direction along 285°.There was slight bending at the western end and two branches at the eastern *** maximum slip is located near the eastern bending area on the northern branch of the fault *** rupture nucleated on the Jiangcuo fault and propagated approximately 160 km along-strike in both the NWW and SEE *** characteristic source rupture process of the Maduo earthquake is similar to that of the 2010 M_(W)6.8 Yushu earthquake,indicating that similar earthquakes with large-expansion surface ruptures and small shallow slip deficits can occur on both the internal fault and boundary fault of the Bayan Har block.

关键词： Maduo earthquake joint inversion coseismic de-formation fault geometry rupture process.

国家持股制度与国有企业民营化--兼评"从公司治理结构看中国国有企业改革"

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特区经济 2004年第8期 54-55页

作者：董延芳武汉大学商学院 430072

一书所载的'从公司治理结构看中国国有企业改革'一文(以下简称文)指出了'无论是从正式、显性的激励机制,还是从非正式、隐性的激励机制看,中国的国有企业改革在解决经营者的短期激励问题方面都是比较成功的.但是,它没有解决经营者的长... 详细信息

一书所载的'从公司治理结构看中国国有企业改革'一文(以下简称文)指出了'无论是从正式、显性的激励机制,还是从非正式、隐性的激励机制看,中国的国有企业改革在解决经营者的短期激励问题方面都是比较成功的.但是,它没有解决经营者的长期激励问题和经营者的选择问题.一个在位经理也许有动力追求短期(但隐藏的)利润,但目前还没有一种机制能够保证只有真正具有企业家才能的人才会被选为经理.根本的原因在于国有企业的经理是由政府官员而非资本家选择的.政府官员有权选择经理却不需为此承担责任,因此他们没有适当的动力去发现和任命有能力的人当经理.而且良好的业绩并不能保证在位经理能一直干下去,从而经理不可能有长期的激励,以国有股为主导的公司化并不能解决国有企业的这些弊端.破产在约束经理方面也没有起到什么作用,因为国有银行既没有动力也没有能力去执行债务合同.为了确保只有那些有能力的人才会成为职业经理并使经理受到恰当的约束,必须把选择经理的权威从政府官员手里转移到真正的资产所有者手中.为此,必须对国有企业和国有银行进行民营化'.

关键词：国家持股制度国有企业民营化《企业理论与中国企业改革》激励机制

Primary Quantitative Study on Earthquake Damage Extracted from Remote Sensing Imagery——A Case Study of Seismic Damage in the Urban Area of Dujiangyan due to the M_S8.0 Wenchuan Earthquake

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Earthquake Research in China 2009年第4期23卷 392-401页

作者： Wang Xiaoqing Wang Long Zhang Xihai Ding Xiang Qiu Hu dong yanfang DouAixia Zhang Feiyu Liu Zaitao Institute of Earthquake Science China Earthquake Administration Beijing 100036 China Earthquake Administration of Jiangsu Province Nanjing 210014 China Earthquake Administration of Tianjin Municipality Tianjin 300201 China China Earthquake Networks Center Beijing 100045 China

The fast developing remote sensing techniques play an increasingly important role in earthquake emergency response, disaster survey and loss estimation. As there is a lack of quantitative studies on seismic damage based on remote sensing, its practicality in seismic disaster management has usually been questioned. The paper introduces the essential quantitative study idea, the concept of the remote sensing seismic damage index （D1RS） and analysis models, demonstrates the seismic damage indices （ D1G ） of buildings obtained from ground surveying and its quantitative relation to D1RS in Dujiangyan city, Sichuan Province, which was destroyed by the 2008 Wenchuan earthquake with Ms8.0. The primary results show that an obvious relationship exists between the D1RS of buildings obtained from the high resolution satellite or aerial remote sensing images and D1G or the building collapse ratio obtained through ground survey, which suggests that the quantitative study on seismic damage based on remote sensing will provide an effective method for seismic damage survey and loss estimation.

关键词： Seismic damage index Remote sensing Wenchuan earthquake Quantitative study

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高速轻载圆柱滚子轴承打滑特性试验与分析

航空动力学报 2023年第12期38卷 2991-2999页

作者：张家铭邱明庞晓旭董艳方河南科技大学机电工程学院河南洛阳471003 机械装备先进制造河南省协同创新中心河南洛阳471003

针对航空发动机圆柱滚子轴承在高速轻载条件下的打滑问题,开展试验与理论研究。基于滚动轴承打滑试验,探究内圈转速、径向载荷对轴承打滑特性的影响。同时考虑轴承工作径向游隙变化,求解滚子受力情况与轴承总力矩,并结合试验结果进行分... 详细信息

针对航空发动机圆柱滚子轴承在高速轻载条件下的打滑问题,开展试验与理论研究。基于滚动轴承打滑试验,探究内圈转速、径向载荷对轴承打滑特性的影响。同时考虑轴承工作径向游隙变化,求解滚子受力情况与轴承总力矩,并结合试验结果进行分析。研究表明,轴承内圈转速低于10000 r/min时,径向载荷增大使轴承工作径向游隙增大,同时加剧轴承打滑程度。随着内圈转速升高,轴承工作径向游隙逐渐减小;存在内圈临界转速,此时轴承打滑率最大。不同径向载荷下内圈临界转速有所差别,本次试验所得内圈临界转速在7000~8000 r/min之间。轴承整体滚子的总力矩直接影响轴承打滑程度。

关键词：打滑特性工作径向游隙圆柱滚子轴承临界转速高速摄影机

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