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Difference Cochains and Reidemeister Traces

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1365-1372页

作者： Baoqun ZHANG xuezhi zhao Department of Mathematics Capital Normal UniversityBeijing 100048China.

The authors consider the difference of Reidemeister traces and difference cochain of given two self-maps, and find out a relation involving these two *** an application, an inductive formula of the Reidemeister traces... 详细信息

关键词： Fixed point Reidemeister trace Difference cochain Spherical manifold

A forcing relation of braids from Nielsen fixed point theory

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Science China Mathematics 2019年第9期62卷 1799-1806页

作者： Jiaoyun Wang xuezhi zhao School of Science Tianjin Chengjian UniversityTianjin300384China Department of Mathematics Capital Normal UniversityBeijing100048China

In this paper, we focus our attention on the connections between the braid group and Nielsen fixed point theory. A new forcing relation between braids is introduced, and we show that it can be fulfilled by using Niels... 详细信息

关键词： braid group fixed point disk fundamental group

On the Kernel of the Borel’s Characteristic Map of Lie Groups

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Communications in Mathematical Research 2023年第2期39卷 173-189页

作者： Haibao Duan xuezhi zhao Yau Mathematical Science Center Tsinghua UniversityBeijing 100084China Academy of Mathematics and Systems Sciences Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences Dalian University of TechnologyDalian 116024China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

For compact and connected Lie group G with a maximal torus T the quotient space G/T is canonically a smooth projective manifold,known as the complete flag manifold of the group *** cohomology ring map c^(∗):H^(∗)(B T)→H∗(G/T)induced by the inclusion c:G/T→B_(T) is called the Borel’s characteristic map of the group G[7,8],where B T denotes the classifying space of *** G be simply-connected and *** on the Schubert presentation of the cohomology H^(∗)(G/T)of the flag manifold G/T obtained in[10,11],we develop a method to find a basic set of explicit generators for the kernel ker c^(∗)⊂H^(∗)(B_(T))of the characteristic map c.

关键词： Lie group flag manifold Schubert calculus

Realization of Fixed Point Sets

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Acta Mathematica Sinica,English Series 1996年第1期12卷 71-76页

作者： zhao xuezhi Department of Mathematics Liaoning University Shenyang, 110036 China Liaoning University

Let f: X→X be a selfmap of a compact connected polyhedron, and A a nonempty closed subset of X. In this paper, we shall deal with the question whether or not there is a map g: X→X homotopic to f such that the fixed point set Fixg of g equals A. We introduce a necessary condition for the existence of such a map g. It is shown that this condition is easy to check, and hence some sufficient conditions are obtained.

关键词： Fixed point sets Nielsen number Local cut points Jiang group

ART-2对滚动轴承振动信号幅值谱的清晰化提取与分类效果研究

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振动与冲击 2007年第1期26卷 139-143,150页

作者：赵学智叶邦彦华南理工大学机械工程学院广州510640

滚动轴承振动信号的幅值谱往往在整个频带上都存在着均匀分布的噪声频率干扰,难以用一般的滤波方法去除,这对轴承实际振动频率成分的识别有很大的影响。通过对ART-2神经网络的分析,指出了在信号中的特征信息相对较强,而噪声相对较弱的... 详细信息

滚动轴承振动信号的幅值谱往往在整个频带上都存在着均匀分布的噪声频率干扰,难以用一般的滤波方法去除,这对轴承实际振动频率成分的识别有很大的影响。通过对ART-2神经网络的分析,指出了在信号中的特征信息相对较强,而噪声相对较弱的情况下,利用ART-2可以对信号中的特征信息成分进行增强,并对噪声进行充分抑制。利用这一原理,实现了对轴承振动信号幅值谱的清晰化提取。对13个轴承振动信号幅值谱的处理实例表明,这种方法获得的模式中轴承实际振动频率成分被清晰地提取了出来,而均布噪声频率则被充分抑制。进一步研究了ART-2的警戒系数对幅值谱清晰化处理效果的影响,并对这种影响机理进行了解释。

关键词： ART-2神经网络轴承振动幅值谱清晰化提取警戒系数

Double-ended passivator enables dark-current-suppressed colloidal quantum dot photodiodes for CMOS-integrated infrared imagers

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InfoMat 2024年第1期6卷 108-122页

作者： Peilin Liu Shuaicheng Lu Jing Liu Bing Xia Gaoyuan Yang Mo Ke xuezhi zhao Junrui Yang Yuxuan Liu Ciyu Ge Guijie Liang Wei Chen Xinzheng Lan Jianbing Zhang Liang Gao Jiang Tang Wuhan National Laboratory for Optoelectronics(WNLO)and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhanthe People's Republic of China Wenzhou Advanced Manufacturing Technology Institute Huazhong University of Science and TechnologyWenzhouthe People's Republic of China School of Physics and Electronic Engineering Hubei University of Arts and ScienceXiangyangthe People's Republic of China School of Integrated Circuits Huazhong University of Science and TechnologyWuhanthe People's Republic of China School of Engineering Physics Shenzhen Technology UniversityShenzhenthe People's Republic of China Optics Valley Laboratory Wuhanthe People's Republic of China Shenzhen Huazhong University of Science and Technology Research Institute Shenzhenthe People's Republic of China

Lead sulfide(PbS)colloidal quantum dot(CQD)photodiodes integrated with silicon-based readout integrated circuits(ROICs)offer a promising solution for the next-generation short-wave infrared(SWIR)imaging *** their potential,large-size CQD photodiodes pose a challenge due to high dark currents resulting from surface states on nonpassivated(100)facets and trap states generated by CQD *** this work,we present a novel approach to address this issue by introducing double-ended ligands that supplementally passivate(100)facets of halidecapped large-size CQDs,leading to suppressed bandtail states and reduced defect *** results demonstrate that the dark current density is highly suppressed by about an order of magnitude to 9.6 nA cm^(2) at -10 mV,which is among the lowest reported for PbS CQD ***,the performance of the photodiodes is exemplary,yielding an external quantum efficiency of 50.8%(which corresponds to a responsivity of 0.532 A W^(-1))and a specific detectivity of 2.5×10^(12) Jones at 1300 *** integrating CQD photodiodes with CMOS ROICs,the CQD imager provides high-resolution(640×512)SWIR imaging for infrared penetration and material discrimination.

关键词： CMOS integration colloidal quantum dots dark current suppression double-ended passivation infrared imager

Analysis on Composition and Content of Glucosinolates in Broccoli Flowers and Leaves

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Asian Agricultural Research 2017年第4期9卷 81-84页

作者： Guangmin LIU Yue MA Yunhua DING Liping HU xuezhi zhao Hongju HE Beijing Vegetable Research Center Beijing Academy of Agriculture and Forestry Sciences/Beijing Key Laboratory of Fruits and Vegetables Preservation and Processing/Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(North China)Ministry of Agriculture/Key Laboratory of Urban Agriculture(North)Ministry of Agriculture

Glucosinolate composition and content were evaluated in flowers and leaves of 12 different broccoli varieties. The results indicated that there were 9 glucosinolates in broccoli,namely Glucoiberin(IBE); Progoitrin(PRO);Sinigrin(SIN);Glucoraphanin(RAA);Gluconapin(NAP);4-Hydroxyglucobrassicin(4OH);Glucobrassicin(GBC);4-Methoxyglucobrassicin(4ME);Neoglucobrassicin(NEO).Total glucosinolate content in flowers was 1-5 times higher than in leaves. The predominant glucosinolate in broccoli was glucoraphanin.

关键词： Broccoli Flowers Leaves Glucosinolates

Glucosinolate Variation in Turnip (Brassica rapa L.) at Different Growing Stages

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Agricultural Biotechnology 2018年第4期7卷 64-68页

作者： xuezhi zhao Hongju HE Pangyuan LIU Wenqi WANG Shuhui SONG Xiangbing MENG Beijing Vegetable Research Center of BAAFS / Key Laboratory of Biology and Genetic Improvement of Horticultural Crops ( North China) Ministry of Agriculture / Key Laboratory of Urban Agriculture ( North) Ministry of Agriculture

The seed, leaf and root parts of three turnip （ Brassica rapa L.） cultivars were analyzed for glucosinolates. The component and concentration of glucosinolates in the three cultivars were also analyzed at different growing stages. Eight kinds of glucosinolates were tested in turnip. They were PRO, NAP, 4OH, GBN, GBC, NAS, 4ME and NEO, respectively. The contents and kinds of glucosinolates varied at different growing stages. The content of NAS was the highest in the seed, GBC and NEO contents were the highest in the seedling, GBN and NEO contents were the highest in the leaf, while the highest NAS content was in the root.

关键词： Turnip Glucosinolates Seed Leaf Root

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舒伯特计数演算的严格基础

中国科学：数学 2022年第8期52卷 865-880页

作者：段海豹赵学志中国科学院数学与系统科学研究院北京100190 大连理工大学数学科学学院大连116024 首都师范大学数学科学学院北京100048

希尔伯特(Hilbert)第15问题要求,为舒伯特(Schubert)计数演算法建立严格基础.其中,长期悬而未解的部分是舒伯特特征数问题.在构建代数几何学的工作中,范·德·瓦尔登(van der Waerden)和韦伊(Weil)将经典的舒伯特演算归结于决定旗流形... 详细信息

希尔伯特(Hilbert)第15问题要求,为舒伯特(Schubert)计数演算法建立严格基础.其中,长期悬而未解的部分是舒伯特特征数问题.在构建代数几何学的工作中,范·德·瓦尔登(van der Waerden)和韦伊(Weil)将经典的舒伯特演算归结于决定旗流形相交理论的问题.本文介绍第15问题的背景、内容以及解答历程.本文的重点是计算特征数的统一公式(定理5.1)以及解答韦伊问题的系统表述(定理5.2).本文通过应用示例5.1和5.2,说明该公式和算法的有效性.

关键词：希尔伯特第15问题舒伯特演算相交(同调)理论舒伯特簇李群

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