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西南大学学报（自然科学版） 2020年第1期42卷 16-21页

作者：许代香贾乐东王瑞马国强段谋正曲存民李加纳西南大学农学与生物科技学院/农业科学研究院

为明确甘蓝型油菜显性核不育两型系D3AB的花器官形态差异和不育材料D3A的花药败育时期与特点,并为进一步研究雄性不育机理奠定基础,分别对D3A与D3B不同时期的花蕾进行了形态学观察及细胞学研究.首先通过体视镜观察发现,D3A与D3B外观形... 详细信息

为明确甘蓝型油菜显性核不育两型系D3AB的花器官形态差异和不育材料D3A的花药败育时期与特点,并为进一步研究雄性不育机理奠定基础,分别对D3A与D3B不同时期的花蕾进行了形态学观察及细胞学研究.首先通过体视镜观察发现,D3A与D3B外观形态无明显差异,均能正常开花,且在雄蕊发育早期均表现正常,后期D3A雄蕊退化萎缩,花粉囊不能正常开裂;不育材料D3A子房柱头发育速度稍快于D3B.通过扫描电镜观察发现,D3A早期花药基部开始皱缩,表皮细胞排列紧密.随着花蕾发育,D3A花粉囊壁表皮细胞逐渐萎缩,最终塌陷且药室不能正常开裂释放花粉;D3B花粉囊始终呈现出紧致饱满状态,花药正常开裂,同时释放出大量成熟花粉粒.通过石蜡切片观察发现,不育材料D3A和可育材料D3B在花蕾发育早期,都能形成花粉母细胞,但与D3B相比,D3A花粉母细胞结构松散,且绒毡层已开始呈现液泡化状态;进入四分体时期,不育材料D3A的花粉囊中观察到高度液泡化的绒毡层细胞,且无四分体结构出现.实验结果表明:绒毡层细胞提前发生了降解而未向分泌型转化,使四分体时期丧失了发育过程中所必需的营养物质,从而不能形成小孢子并发育为成熟的花粉粒进行释放,因此认为D3A的败育属于绒毡层发育异常类型.

关键词：显性核不育花药败育绒毡层细胞学观察

Intermittent Arc Fault Detection Based on Machine Learning in Resonant Grounding Distribution Systems

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 599-611页

作者： Ye Tian mou-Fa Guo duan-Yu Chen College of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China Department of Electrical Engineering Yuan Ze UniversityTaiwan 32003China Fuzhou Power Supply Company of State Grid Fujian Electric Power Co. Ltd.Fuzhou 350009China

In resonant grounding systems,most single-phaseto-ground faults evolve from IAFs(Intermittent Arc Faults).Earlier detection of IAFs can facilitate fault *** work proposes a novel method based on machine learning for detecting IAFs in three ***,the feature of zero-sequence current is automatically extracted and selected by a newlydesigned FINET(“For IAFs,Neuron Elaboration Net”),instead of traditional feature selection based on time-frequency ***,data of the zero-sequence current divided by different time windows are successively input into the trained FINET.A proposed PSF(principal-subordinate factor)analyses the results obtained from FINET to improve anti-interference in the mentioned IAF detection *** using PSCAD/EMTDC software simulation data show the proposed method is feasible and highly *** addition,the detection result of on-site recorded data demonstrates the effectiveness of the proposed method in practical resonant grounding systems.

关键词： Resonant grounding distribution systems intermittent arc faults(IAFs)detection “For IAFs Neuron Elaboration Net”(FINET) principal-subordinate factor(PSF)

Distribution of Triplet Separators in Bacterial Genomes

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Communications in Theoretical Physics 2001年第7期36卷 115-118页

作者： HU Rui zheng Wei-mou Institute of Theoretical Physics Academia Sinica Beijing 100080 China Institute of Theoretical Physics Academia Sinica Beijing 100080 China

Distributions of triplet separator lengths for two bacterial complete genomes are analyzed. The theoretical distributions for the independent random sequence and the first-order Markov chain are derived and compared with the distributions of the bacterial genomes. A prominent double band structure, which does not exist in the theoretical distributions, is observed in the bacterial distributions for most triplets.

关键词： bacterial genomes, DNA sequence analysis

More Detailed Disturbance Measurement and Active Disturbance Rejection Altitude Control for a Flapping Wing Robot Under Internal and External Disturbances

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Journal of Bionic Engineering 2022年第6期19卷 1722-1735页

作者： Jiawang mou Weiping Zhang Kexin zheng Yao Wang Chaofeng Wu National Key Laboratory of Science and Technology on Micro/Nano Fabrication Shanghai Jiao Tong University800 Dongchuan RoadShanghai200240China Department of Micro/Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong University800 Dongchuan RoadShanghai200240China

With the goal of designing a biologically inspired robot that can hold a stable hover under internal and external *** designed a tailless Flapping-wing Micro Aerial Vehicle(FMAV)with onboard 3D velocity *** this way,the wind disturbance caused by the relative motion of the FMAV can be quantified in real time based on the established altitudinal dynamics *** the rest of the total disturbance,an active disturbance rejection controller is proposed to estimate and suppress those *** comparison with the traditional PID controller,this proposed approach has been *** results show that,in the hovering flight with the internal unmodeled dynamics,the root-mean-square of height controlled is only 2.53 *** with the different weights of loads mounting on the FMAV,the ascending trajectory of flights remains impressively *** the forward flight with the external disturbance,the root-mean-square error of height controlled is 2.78 *** the FMAV flies over a ladder introducing an abrupt external disturbance,the maximum overshoot is only half of that controlled by the PID *** our best knowledge,this is the first demonstration of FMAVs with the capability of sensing motion-generated wind disturbance onboard and handling the internal and external disturbances in hover flight.

关键词： Bionic robot Flapping wing 3D velocity measurement Disturbance estimation and rejection Altitude control

Electrical transport and photoresponse properties of single-crystalline p-type Cd_3As_2 nanowires

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Science China(Physics,Mechanics & Astronomy) 2015年第2期58卷 95-100页

作者： duan TingYuan LOU zheng SHEN GuoZhen Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology State Key Laboratory for Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences

Cd3As2 is an important II-V group semiconductor with excellent electrical and optoelectronic properties. In this work, we report the large scale growth of single-crystalline Cd3As2 nanowires via a simple chemical vapor deposition method. Single nanowire field-effect transistors were fabricated with the as-grown Cd3As2 nanowires, which exhibited a high lon/loff of 104 with a hole mobility of 6.02 cm2V-1s-1. Photoresponse properties of the Cd3As2 nanowires were also investigated by illuminating the nanowires with white light by varying intensities. Besides, flexible photodetectors were also fabricated on flexible PET substrate, showing excellent mechanical stablility and flexible electro-optical properties under various bending states and bending cycles. Our results indicate that Cd3As2 nanowires can be the basic material of next generation electronic and ootoelectronic devices.

关键词： nanowires electrical transport photodetector

Fe_(n)Mo_(38-n)(n=0-38)及Fe_(n)Mo_(55-n)(n=0-55)双金属团簇的结构演化和基态能量

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原子与分子物理学报 2025年第3期42卷 85-93页

作者：郑琪琪陈轩程彪段海明新疆大学物理科学与技术学院乌鲁木齐830017

基于半经验的Gupta多体势,采用遗传算法及分子动力学淬火算法,系统研究了(FeMo)m(m=38及55)双金属团簇的基态结构及其能量.结果表明:对于Fe_(n)Mo_(38-n)(n=0-38)团簇,随Fe原子数的增加,Fe原子优先占据团簇表面再占据内部,其基态构型存... 详细信息

基于半经验的Gupta多体势,采用遗传算法及分子动力学淬火算法,系统研究了(FeMo)m(m=38及55)双金属团簇的基态结构及其能量.结果表明:对于Fe_(n)Mo_(38-n)(n=0-38)团簇,随Fe原子数的增加,Fe原子优先占据团簇表面再占据内部,其基态构型存在类O_(h)结构、类I_(h)结构和无序结构间的竞争.对于Fe_(n)Mo_(55-n)(n=0-55)团簇,随Fe原子数的增加,Fe原子优先占据团簇中心位置,再依次占据表面顶点、棱边和次外层,双金属团簇基态构型主要体现为在Mackay二十面体基础上的结构畸变.Fe_(24)Mo_(14),Fe_(13)Mo_(42)和Fe_(43)Mo_(12)为幻数结构团簇,研究发现双金属团簇幻数成因不能通过单质团簇常用的平均配位数和平均键长模型解释,它更多的归咎于组分效应导致的结构高对称性.

关键词：双金属团簇结构和能量淬火算法遗传算法

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Fe_(n)Co_(55-n)与Co_(n)Mo_(55-n)(n=0~55)团簇基态的能量与结构演化

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原子与分子物理学报 2025年第5期42卷 57-66页

作者：程彪郑琪琪陈轩段海明新疆大学物理科学与技术学院乌鲁木齐830049

采用半经验的Gupta多体势函数结合遗传算法及分子动力学淬火算法,系统研究了Co_(n)Mo_(55-n)(n=0~55)与Fe_(n)Co_(55-n)(n=0~55)团簇的基态结构与能量.通过分析基态结构的相似函数、质心间距、平均键长、平均原子配位数、平均结合能、... 详细信息

采用半经验的Gupta多体势函数结合遗传算法及分子动力学淬火算法,系统研究了Co_(n)Mo_(55-n)(n=0~55)与Fe_(n)Co_(55-n)(n=0~55)团簇的基态结构与能量.通过分析基态结构的相似函数、质心间距、平均键长、平均原子配位数、平均结合能、混合能与二阶差分能.探究了团簇基态的结构特征及稳定性与团簇所含元素种类及组分的关联.结果表明:对Co-Mo混合团簇,随Co原子数目增加,Co原子依次占据团簇中心与最外层顶点,混合团簇逐渐出现组分偏析与无序现象;对Fe-Co混合团簇,基态结构主体上均体现为围绕Mackay二十面体构型的结构畸变,随Fe原子含量增加,Fe原子先占据团簇外表面顶点位置直到全部包裹Co原子,逐渐形成核壳式结构;Co_(13)Mo_(42)与Fe_(42)Co_(13)是幻数结构团簇,研究发现组分效应导致的团簇高对称性相比团簇平均键长与平均原子配位数更能解释幻数结构的成因.

关键词：遗传算法淬火算法双金属团簇基态结构

Formation of silacycles via metal-mediated or catalyzed Si-C bond cleavage

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Chinese Science Bulletin 2013年第3期58卷 307-315页

作者： WANG LiLi duan zheng College of Chemistry and Molecular Engineering Zhengzhou University

Silacycles play a very important role in modern organic chemistry and materials *** of silacyclic skeletons via metal-mediated or catalyzed Si-C bond cleavage has attracted much recent *** interesting and useful synthetic strategies have been reported in the *** this review,we have summarized recent developments on metal-mediated or catalyzed Si-C bond cleavage,which lead to the synthesis of silacycles,including silacyclobutenes,silacyclopentanes,silacyclopentadienes(siloles),6-membered silacycles,and their derivatives.

关键词：键断裂介导金属材料科学有机化学衍生物催化合成

Joint Sample Position Based Noise Filtering and Mean Shift Clustering for Imbalanced Classification Learning

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Tsinghua Science and Technology 2024年第1期29卷 216-231页

作者： Lilong duan Wei Xue Jun Huang Xiao zheng School of Computer Science and Technology Anhui University of TechnologyMaanshan 243032China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China

The problem of imbalanced data classification learning has received much *** classification algorithms are susceptible to data skew to favor majority samples and ignore minority *** weighted minority oversampling technique(MWMOTE)is an effective approach to solve this problem,however,it may suffer from the shortcomings of inadequate noise filtering and synthesizing the same samples as the original minority *** this end,we propose an improved MWMOTE method named joint sample position based noise filtering and mean shift clustering(SPMSC)to solve these ***,in order to effectively eliminate the effect of noisy samples,SPMsC uses a new noise filtering mechanism to determine whether a minority sample is noisy or not based on its position and distribution relative to the majority *** that MWMOTE may generate duplicate samples,we then employ the mean shift algorithm to cluster minority samples to reduce synthetic replicate ***,data cleaning is performed on the processed data to further eliminate class *** on extensive benchmark datasets demonstrate the effectiveness of SPMsC compared with other sampling methods.

关键词： imbalanced data classification oversampling noise filtering clustering