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基于径向力反馈的无轴承异步主轴电机悬浮控制

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电工技术学报 2016年第6期31卷 91-99页

作者：詹立新周凯清华大学精仪系北京100084

针对传统无轴承异步电机径向悬浮力控制受转矩绕组磁场定向准确性影响、系统控制延迟导致相位裕度降低等问题，提出一种基于径向力反馈的无轴承异步主轴电机悬浮控制方法。通过探测线圈法检测两套绕组的气隙磁链分量，依此计算出两套绕... 详细信息

针对传统无轴承异步电机径向悬浮力控制受转矩绕组磁场定向准确性影响、系统控制延迟导致相位裕度降低等问题，提出一种基于径向力反馈的无轴承异步主轴电机悬浮控制方法。通过探测线圈法检测两套绕组的气隙磁链分量，依此计算出两套绕组产生的径向悬浮力大小，并将其作为反馈信号引入到悬浮闭环控制系统中，从而有效消除由系统控制延迟导致的相位裕度降低的影响。仿真和实验结果验证了所提出控制方法的有效性。实验结果表明，相比常规悬浮控制系统，基于径向力反馈的无轴承异步主轴电机悬浮控制系统具有更好的响应性能、阻尼特性及鲁棒性。

关键词：无轴承异步主轴电机径向力反馈悬浮控制探测线圈

Theoretical Comparison of Oxygen Adsorption on Cu（100） Surface

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Chinese Journal of Chemical Physics 2006年第1期19卷 54-58页

作者： Wen-kai Chen Chun-hai Lu zhan-hong Chen Yi Li Jun-qian Li Department of Chemistry Fuzhou University Fuzhou 350002 China China Academy of Engineering Physics Mianyang 521900 China State Key Laboratory of Structural Chemistry Fuzhou 3500021 China

The interaction of atomic oxygen with the clean Cu（100） surface has been studied by means of cluster and periodic slab models density functional theory in the present paper. The Cu（4,9,4） cluster and a three-layer slab with c（2×2） structure are used to model the perfect Cn（100） surface. Three possible adsorption sites, top, bridge and hollow site, were considered in the calculations. The predicted results show that the hollow site is the prefer site for atomic oxygen adsorbed on Cu（100） surface energetically. This is in good agreement with the experiment. The calculated binding energies are respective 2.014, 3.154 and 3.942 eV for top, bridge and hollow sites at mPW1PW91/LanL2dz level for the cluster model. The geometry of Cu（100） surface has also been optimized theoretically with various density functional rnethods and the results show that the prediction from the B3PW91/LanL2dz and mPWlPW91/LanL2dz reproduce the experimental observation. The frontier molecular orbitals and partial density of states analysis show that the electron transfer from the d orbital of substrate to the p orbital of the surface oxygen atom.

关键词： Oxygen Density functional theory Cu(100) surface Adsorption

The Role of Processing Solvent on Morphology Optimization for Slot-Die Printed Organic Photovoltaics

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Chinese Journal of Polymer Science 2023年第6期41卷 842-850,I0005页

作者： Lei Wang Jun-Zhe zhan Wen-kai Zhong Lei Zhu Guan-Qing Zhou Tian-Yu Hao Ye-Cheng Zou Zhen-Hua Wang Gang Wei Yong-Ming zhang Feng Liu School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Frontiers Science Center for Transformative Molecules Center of Hydrogen ScienceSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai200240China State Key Laboratory of Fluorinated Functional Membrane Materials and Dongyue Future Hydrogen Energy Materials Company Zibo 256401China

The morphology manipulation of the active layers is important for improving the performance of organic photovoltaics(OPVs).The choice of processing solvent has great impact on the crystallization and phase separation during film formation,since solvent properties,including solvent effect on molecular crystallization,boiling point,and interaction parameters,can directly change the evolution pathways associated with thermodynamics and ***,revealing the underlying solvent-regulated morphology mechanism is potential to provide guiding strategies for device *** this study,chloroform,chlorobenzene,and toluene are used to process PM6:Y6 blends by slot-die printing to fabricate OPV *** chloroform printed film forms a fibrillar network morphology with enhanced crystallization,facilitating exciton dissociation,charge transport and extraction,resulting in an optimal power conversion efficiency of 16.22%.However,the addition of the additive chloronaphthalene in chloroform solution leads to over-crystallization of Y6,and thus,increasing domain size that exceeds the exciton diffusion length,resulting in lower device *** addition,both the chlorobenzene and toluene suppress the crystallization of Y6,which drastically decreased short-circuit current and fill *** results demonstrate the important role of processing solvent in dictating film morphology,which critically connects with the resultant printed OPV performance.

关键词： crystallization chloroform film

Highly efficient flexible perovskite solar cells with vacuum-assisted low-temperature annealed SnO2 electron transport layer

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Journal of Energy Chemistry 2022年第4期31卷 1-7页

作者： Xiaoguo Li Zejiao Shi Fatemeh Behrouznejad Mohammad Hatamvand Xin zhang Yaxin Wang Fengcai Liu Haoliang Wang kai Liu Hongliang Dong Farhan Mudasar Jiao Wang Anran Yu Yiqiang zhan Center for Micro Nano Systems School of Information Science and Technology(SIST)Fudan UniversityShanghai 200433China Academy for Engineering&Technology Fudan UniversityShanghai 200433China Center for High Pressure Science and Technology Advanced Research PudongShanghai 201203China

The demand for lightweight, flexible, and high-performance portable power sources urgently requires high-efficiency and stable flexible solar cells. in the case of perovskite solar cells(PSCs), most of the common electron transport layer(ETL) needs to be annealed for improving the optoelectronic properties,while conventional flexible substrates could barely stand the high temperature. Herein, a vacuumassisted annealing SnO_(2) ETL at low temperature(100℃) is utilized in flexible PSCs and achieved high efficiency of 20.14%. Meanwhile, the open-circuit voltage(V_(oc)) increases from 1.07 V to 1.14 V. The flexible PSCs also show robust bending stability with 86.8% of the initial efficiency is retained after 1000 bending cycles at a bending radius of 5 mm. X-ray photoelectron spectroscopy(XPS), atomic force microscopy(AFM), and contact angle measurements show that the density of oxygen vacancies, the surface roughness of the SnO_(2) layer, and film hydrophobicity are significantly increased, respectively. These improvements could be due to the oxygen-deficient environment in a vacuum chamber, and the rapid evaporation of solvents. The proposed vacuum-assisted low-temperature annealing method not only improves the efficiency of flexible PSCs but is also compatible and promising in the large-scale commercialization of flexible PSCs.

关键词： Flexible perovskite solar cells Vacuum-assisted Electron transport layer Trap-assisted recombination

A comprehensive evaluation of factors affecting the accuracy of pig genotype imputation using a single or multi-breed reference population

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Journal of integrative Agriculture 2022年第2期21卷 486-495页

作者： zhanG kai-li PENG Xia zhanG Sai-xian zhan Hui-wen LU Jia-hui XiE Sheng-song ZHAO Shu-hong Li Xin-yun MA Yun-long Key Laboratory of Agricultural Animal Genetics Breeding and ReproductionMinistry of Education/Key Laboratory of Swine Genetics and BreedingMinistry of Agriculture and Rural Affairs/College of Animal Science and TechnologyHuazhong Agricultural UniversityWuhan 430070P.R.China

Genotype imputation has become an indispensable part of genomic data analysis. in recent years, imputation based on a multi-breed reference population has received more attention, but the relevant studies are scarce in pigs. in this study, we used the illumina Porcine SNP50 Bead Chip to investigate the variations of imputation accuracy with various influencing factors and compared the imputation performance of four commonly used imputation software programs. The results indicated that imputation accuracy increased as either the validation population marker density, reference population sample size, or minor allele frequency(MAF) increased. However, the imputation accuracy would have a certain extent of decrease when the pig reference population was a mixed group of multiple breeds or lines. Considering both imputation accuracy and running time, Beagle 4.1 and Fimpute are excellent choices among the four software packages tested. This work visually presents the impacts of these influencing factors on imputation and provides a reference for formulating reasonable imputation strategies in actual pig breeding.

关键词： genotype imputation multi-breed reference population imputation accuracy

终身寿险退保的利率敏感性分析——基于保单保障水平的测算

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广东金融学院学报 2010年第4期25卷 117-128页

作者：展凯广东外语外贸大学保险系

市场利率变化对于不分红终身寿险产品退保的影响很大，终身寿险保单不能够通过选择较长的缴费期来缓解市场利率变化引起的退保压力，调整预定利率能缓解退保压力；适当的分红政策能够大大缓解市场利率变化对分红型终身寿险退保的影响，... 详细信息

市场利率变化对于不分红终身寿险产品退保的影响很大，终身寿险保单不能够通过选择较长的缴费期来缓解市场利率变化引起的退保压力，调整预定利率能缓解退保压力；适当的分红政策能够大大缓解市场利率变化对分红型终身寿险退保的影响，但是经营效益差，分红水平低于市场预期的寿险公司产品可能会遭遇到更大的退保压力。

关键词：终身寿险退保利率保障水平

A syncretic representation for image classification and face recognition

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CAAi Transactions on intelligence Technology 2016年第2期1卷 173-178页

作者： Zhongli Ma Quanyong Liu kai Sun Sui zhan College of Automation Harbin Engineering University Harbin China Shenzhen Sunwin intelligent Corporation Shenzhen China College of Computer Science and Electronic Engineering Hunan University Changsha China

For representation based image classification methods, it is very important to well represent the target image. As pixels at same positions of training samples and test samples of an object usually have different intensities, it brings difficulty in correctly classifying the object. in this paper, we proposed a novel method to reduce the effects of this issue for image classification. Our method first produces a new representation （i.e. virtual image） of original image, which can enhance the importance of moderate pixel intensities and reduce the effects of larger or smaller pixel intensities. Then virtual images and corresponding original images are respectively used to represent a test sample and obtain two rep- resentation results. Finally, this method fuses these two results to classify the test sample. The integration of original image and its virtual image is able to improve the accuracy of image classification. The experiments of image classification show that the proposed method can obtain a higher accuracy than the conventional classification methods.

关键词： image syncretic representation Pixel intensity image classification Face recognition

从血缘关系到契约关系:民族体育传承的现代演绎思辨

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贵州民族研究 2018年第3期39卷 95-98页

作者：展凯山东大学山东威海264209

随着民族传统体育原有的传承模式解构,在各种因素推动下又形成了新的学校传承、社团传承等模式,虽然传承形式有不同,但是从根本上来说,从血缘关系到契约关系的转变是民族体育现代传承的基本趋势。这个趋势形成主要是因为民族体育的进步... 详细信息

随着民族传统体育原有的传承模式解构,在各种因素推动下又形成了新的学校传承、社团传承等模式,虽然传承形式有不同,但是从根本上来说,从血缘关系到契约关系的转变是民族体育现代传承的基本趋势。这个趋势形成主要是因为民族体育的进步发展需要、民族社会环境趋势、民族体育功能转变以及民族体育推广发展等因素共同促成。血缘关系传承和契约关系传承有质的不同,两者各有优势,在少数民族传统体育的契约传承过程中,必然会由于契约关系的理性特征而缺失血缘传承的一些基本优势,因此在民族体育从血缘关系到契约关系的传承转变过程中,必须要通过各种方式保留血缘传承的优势。

关键词：血缘契约民族体育传承

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中国社会保障基金的平稳增长路径

财经理论与实践 2008年第3期29卷 30-33页

作者：展凯广东外语外贸大学国际经济与贸易学院广东广州510006

通过建立一个包含人口老龄化因素的两期迭代模型,推导出我国现阶段养老保险体系下社会保障基金的平衡增长路径,进而分析人口老龄化因素对社会保障基金平稳增长路径的影响。结论显示,当经济增长率大于投资回报率时,人均社会保障基金与工... 详细信息

通过建立一个包含人口老龄化因素的两期迭代模型,推导出我国现阶段养老保险体系下社会保障基金的平衡增长路径,进而分析人口老龄化因素对社会保障基金平稳增长路径的影响。结论显示,当经济增长率大于投资回报率时,人均社会保障基金与工资额的比率将趋近或等于某一确定水平,在人口老龄化环境下部分积累制是可行的,提高社会保障费率不能缓解人口老龄化对养老体系的冲击。

关键词：部分积累老龄化社保基金增长路径