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COMPLEX SYSTEM ANALYSIS OF MARKET RETURN PERCOLATION MODEL ON SIERPINSKI CARPET LATTICE FRACTAL

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Journal of Systems Science & Complexity 2014年第4期27卷 743-759页

作者： dong yanfang WANG Jun Department of Mathematics College of ScienceBeijing Jiaotong University

This paper investigates the statistical behaviors of fluctuations of price changes in a stock *** Sierpinski carpet lattice fractal and the percolation system are applied to develop a new random stock price for the financial *** Sierpinski carpet is an infinitely ramified fractal and the percolation theory is usually used to describe the behavior of connected clusters in a random *** authors investigate and analyze the statistical behaviors of returns of the price model by some analysis methods,including multifractal analysis,autocorrelation analysis,scaled return interval ***,the authors consider the daily returns of Shanghai Stock Exchange Composite Index,and the comparisons of return behaviors between the actual data and the simulation data are exhibited.

关键词： Percolation return Sierpinski carpet lattice fractal statistical analysis stock market.

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工况参数对高速角接触球轴承温升特性的影响

轴承 2024年第10期 32-38页

作者：董艳方何恺邱明马亚飞于伟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

以润滑油温度、转速、径向载荷、轴向载荷和喷油量等工况参数为变量进行温升试验,分析工况因素对高速角接触球轴承温升特性的影响规律,并应用灰色关联度方法研究不同工况参数对轴承温升的影响程度。试验结果表明:喷油量与轴承温升之间... 详细信息

以润滑油温度、转速、径向载荷、轴向载荷和喷油量等工况参数为变量进行温升试验,分析工况因素对高速角接触球轴承温升特性的影响规律,并应用灰色关联度方法研究不同工况参数对轴承温升的影响程度。试验结果表明:喷油量与轴承温升之间呈非线性关系;存在最佳轴向预紧力使轴承的温升较低,不同转速条件下轴承达到最优预紧状态所需要的轴向载荷不同;各工况参数对轴承温升的影响程度从大到小为润滑油温度、转速、喷油量、轴向载荷、径向载荷。

关键词：滚动轴承角接触球轴承灰色关联分析温升试验温度载荷转速

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基于模糊理论的立式磁轴承系统保护轴承抗冲击影响因素分析

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轴承 2024年第10期 55-64页

作者：朱定康庞晓旭黄昆邱明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 高端轴承河南省协同创新中心河南洛阳471003 洛阳轴承研究所有限公司河南洛阳471039

为分析立式磁轴承失效后保护轴承受转子冲击的影响因素及其影响程度,仿真立式磁轴承系统中转子跌落至保护轴承的动力学过程,建立Ⅰ-Ⅱ级模糊综合评价模型对保护轴承所受轴向碰撞力各影响参数的影响程度进行评判,并利用熵权法、灰色关联... 详细信息

为分析立式磁轴承失效后保护轴承受转子冲击的影响因素及其影响程度,仿真立式磁轴承系统中转子跌落至保护轴承的动力学过程,建立Ⅰ-Ⅱ级模糊综合评价模型对保护轴承所受轴向碰撞力各影响参数的影响程度进行评判,并利用熵权法、灰色关联度法对模型进行验证,结果表明:随着转子质量、轴向保护间隙、转子偏心角度增大以及有保持架更换为无保持架,保护轴承内圈所受最大轴向碰撞力增大,随着填球数增大,最大轴向碰撞力先减小后增大,而转子转速、滚动体材料、径向保护间隙的变化对轴向碰撞力的影响不大;各参数的影响程度从大到小为转子质量、保护轴承填球数、轴向保护间隙、转子偏心角度、保护轴承有无保持架、滚动体材料、转子转速、径向保护间隙;模糊综合评价模型与熵权法、灰色关联度法的评价结果基本一致,验证了在乏信息条件下利用模糊综合评价模型评价各参数对保护轴承所受轴向碰撞力的影响程度的有效性。

关键词：滚动轴承磁力轴承模糊综合评价方法系统动力学模型碰撞力仿真

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

基于光纤传感的航发齿轮动应力测试与振动特性研究

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现代制造技术与装备 2024年第9期60卷 41-44页

作者：赵虎王轶翔董艳方马亚飞成都航利(集团)实业有限公司成都611000 河南科技大学机电工程学院洛阳471003 河南科技大学机械装备先进制造河南省协同创新中心洛阳471003

基于光纤传感技术,研究高速圆柱齿轮辐板动应力测试方法,并针对某型发动机附件传动圆柱齿轮齿根裂纹故障问题,测量得到该齿轮在实际工况下的动应力数据。结果表明:随着转速的增加,齿轮副表现出异常振动状态;实验所得数据的频谱分析显示... 详细信息

基于光纤传感技术,研究高速圆柱齿轮辐板动应力测试方法,并针对某型发动机附件传动圆柱齿轮齿根裂纹故障问题,测量得到该齿轮在实际工况下的动应力数据。结果表明:随着转速的增加,齿轮副表现出异常振动状态;实验所得数据的频谱分析显示,主要分频在8100 Hz附近幅值具有明显变化;啮合频率(8047 Hz)与第3节径固有频率(8313.9 Hz)接近,推断故障齿轮在转速14200 r·min^(-1)下存在3节径共振。

关键词：光纤光栅航空发动机动应力测试固有频率共振

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

鸢尾属8个品种花粉生活力及柱头可授性比较分析

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分子植物育种 2024年第7期22卷 2322-2329页

作者：周琴董艳芳张冬林毛静徐冬云周媛童俊彭宇李清源许林武汉市农业科学院林业果树研究所武汉430075 美国乔治亚大学园艺系美国雅典30602

为探索鸢尾属不同品种的花粉生活力及柱头可授性,从而提高其杂交效率,本研究以鸢尾属中的8个德国鸢尾(Iris germanica)品种为试验材料,利用KI-I2、TTC、液体培养基萌发法检测不同鸢尾品种的花粉生活力,同时利用联苯胺-过氧化氢法对不同... 详细信息

为探索鸢尾属不同品种的花粉生活力及柱头可授性,从而提高其杂交效率,本研究以鸢尾属中的8个德国鸢尾(Iris germanica)品种为试验材料,利用KI-I2、TTC、液体培养基萌发法检测不同鸢尾品种的花粉生活力,同时利用联苯胺-过氧化氢法对不同鸢尾品种的柱头可授性进行比较分析。KI-I2染色结果表明,8个鸢尾品种的花粉均被着色,其中‘荞麦’(Buckwheat)、‘康康’(French Cancan)、‘秋季马戏团’(Autumn Circus)和‘再次祝福’(Blessed Again)花粉活性较高,分别为95.4%、94.1%、93.9%和90.5%,其次为‘威廉姆森’(Williams)、‘金娃娃’(Gold Boy)、‘黑骑士’(Black Knight)和‘杰西之歌’(Jesse's Song),分别为86.9%、86.0%、83.1%、80.0%;0.5%、1.0%和2.0%TTC染色液均不能使鸢尾花粉着色;以黑骑士花粉为例筛选其最适液体培养基组合为K (140 g/L蔗糖+0.01 g/L硼酸);不同鸢尾品种花粉萌发率从高到低依次为‘康康’38.1%、‘荞麦’34.1%、‘杰西之歌’26.5%、‘威廉姆森’20.8%、‘秋季马戏团’17.9%、‘再次祝福’16.0%、‘黑骑士’15.2%和‘金娃娃’12.8%。柱头可授性研究结果表明,‘康康’、‘荞麦’、‘秋季马戏团’和‘杰西之歌’柱头可授性较高,其次为‘金娃娃’,而‘再次祝福’、‘威廉姆森’和‘黑骑士’柱头可授性较低。本研究为鸢尾杂交育种提供了科学的依据,有利于鸢尾新品种的培育。

关键词：鸢尾花粉活力花粉萌发柱头可授性