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Hausdorff Dimension of the M-Set of λexp(z)

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Acta Mathematica Sinica,English Series 1994年第4期10卷 362-368页

作者： weiyuan, qiu Department of Mathematics Fudan University Shanghai China

We show that the set of λ-values for which λ exp(z)does not have stable regions has Hausdorff dimension two,and that the set of λ-values for which λ sin(z)does not have stable regions has a positive area.

关键词： exp Th Hausdorff Dimension of the M-Set of

Proof of the Branner-Hubbard conjecture on Cantor Julia sets

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Science China Mathematics 2009年第1期52卷 45-65页

作者： qiu weiyuan YIN YongCheng School of Mathematical Sciences Fudan UniversityShanghai 200433China

By means of a nested sequence of some critical pieces constructed by Kozlovski, Shen, and van Strien, and by using a covering lemma recently proved by Kahn and Lyubich, we prove that a component of the filled-in Julia set of any polynomial is a point if and only if its forward orbit contains no periodic critical components. It follows immediately that the Julia set of a polynomial is a Cantor set if and only if each critical component of the filled-in Julia set is aperiodic. This result was a conjecture raised by Branner and Hubbard in 1992.

关键词： Julia set Branner-Hubbard conjecture puzzle tableau 37F10 37F20

Quasisymmetric geometry of the Julia sets of McMullen maps Dedicated to the Memory of Professor Lei Tan

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Science China Mathematics 2018年第12期61卷 2283-2298页

作者： weiyuan qiu Fei Yang Yongcheng Yin School of Mathematical Sciences Fudan University Department of Mathematics Nanjing University School of Mathematical Sciences Zhejiang University

We study the quasisymmetric geometry of the Julia sets of McMullen maps f_λ(z) = z^m+ λ/z~?,where λ∈ C \ {0} and ? and m are positive integers satisfying 1/? + 1/m < 1. If the free critical points of f_λ are escaped to the infinity, we prove that the Julia set J_λ of f_λ is quasisymmetrically equivalent to either a standard Cantor set, a standard Cantor set of circles or a round Sierpiński carpet(which is also standard in some sense).If the free critical points are not escaped, we give a sufficient condition on λ such that J_λ is a Sierpiński carpet and prove that most of them are quasisymmetrically equivalent to some round carpets. In particular, there exist infinitely renormalizable rational maps whose Julia sets are quasisymmetrically equivalent to the round carpets.

关键词： Julia sets Sierpiński carpet quasisymmetrically equivalent

捕获分支是拟圆:具有临界不动点的三次多项式献给杨乐教授80华诞

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中国科学：数学 2019年第10期49卷 1431-1438页

作者：王悦洋邱维元复旦大学数学科学学院

按Milnor分类,具有有限临界不动点的三次多项式的参数平面中,有界双曲分支可以分为三类:主双曲分支、捕获分支、非捕获分支. Roesch证明了主双曲分支边界具有稠密尖点,本文证明捕获分支的边界是拟圆周,从而没有尖点.同时,非捕获分支的... 详细信息

按Milnor分类,具有有限临界不动点的三次多项式的参数平面中,有界双曲分支可以分为三类:主双曲分支、捕获分支、非捕获分支. Roesch证明了主双曲分支边界具有稠密尖点,本文证明捕获分支的边界是拟圆周,从而没有尖点.同时,非捕获分支的边界是一条解析曲线(至多有一个例外的尖点).

关键词：三次多项式双曲分支捕获分支拟圆周尖点全纯运动

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税收安全视角下的风险指数：原理与框架设计

税收经济研究 2019年第5期24卷 66-71页

作者：丘伟元国家税务总局广州市税务局税收科学研究所

文章结合当前税收风险管理重点工作,提出了一种指数化描述税收风险水平的思路和方法,进而构建了一套综合反映区域税收风险情况的评价指标和评价方式。通过运用税收风险指数,有利于把脉风险状况,合理配置资源,转变征管方式,把握不同地区... 详细信息

文章结合当前税收风险管理重点工作,提出了一种指数化描述税收风险水平的思路和方法,进而构建了一套综合反映区域税收风险情况的评价指标和评价方式。通过运用税收风险指数,有利于把脉风险状况,合理配置资源,转变征管方式,把握不同地区、类型、行业、税种、事项等涉税风险的特征规律和变化趋势,以防范和化解税收风险,维护税收安全。

关键词：国家安全观税收风险税收管理

Connectivity of the Mandelbrot set for the family of renormalization transformations

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Science China Mathematics 2010年第3期53卷 849-862页

作者： WANG XiaoGuang 1,qiu weiyuan 1 , YIN YongCheng 1 , QIAO JianYong 2 & GAO JunYang 2 1 School of Mathematical Sciences, Fudan University, Shanghai 200433, China 2 Center of Mathematics, China University of Mining and Technology, Beijing 100083, China School of Mathematical Sciences Fudan University Shanghai China Center of Mathematics China University of Mining and Technology Beijing China

We show that the Mandelbrot set for the family of renormalization transformations of 2-dimensional diamond-like hierachical Potts models in statistical mechanics is connected. We also give an upper bound for the Hausd... 详细信息

关键词： connectivity Mandelbrot set renormalization transformations

基于Teamcenter Process Simulate数字化智能生产线仿真设计

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软件 2023年第1期44卷 11-15页

作者：周宝昌邱伟源谢智阳河源职业技术学院广东河源517000 河源市工业机器人技术应用工程技术研究中心广东河源517000

通常企业必须先获取实体产品,才能对产品的质量和建造过程进行检查,而这意味着成本和风险的增加,本文利用数字孪生模型来解决这个问题。运用自动化设备的数字化建模和开发技术,实现产品开发过程的可预测性,节约大量调试时间和物料成本... 详细信息

通常企业必须先获取实体产品,才能对产品的质量和建造过程进行检查,而这意味着成本和风险的增加,本文利用数字孪生模型来解决这个问题。运用自动化设备的数字化建模和开发技术,实现产品开发过程的可预测性,节约大量调试时间和物料成本。本文通过Tecnomatix产线仿真系统,将工业机器人与自动化生产设备进行工艺规划,实现以虚拟方式开发、仿真和调试机器人和其他自动化制造系统,减少了大量编程时间,还减少大量的实际调试次数和时间,提高了整个工艺开发过程的效率。本仿真系统实现整个货物工业产线的步骤可控性、可视性,同时利用好中转台从而真实模拟产线进行连续不断的进行生产,将大大提高了实际生产中的效率。

关键词：数字孪生产线仿真数字化建模

A Footpad Structure with Reusable Energy Absorption Capability for Deep Space Exploration Lander:Design and Analysis

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 257-270页

作者： weiyuan Dou Xiaohang qiu Zhiwei Xiong Yanzhao Guo Lele Zhang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China National International Science and Technology Cooperation Base on Railway Vehicle Operation Engineering Beijing Jiaotong UniversityBeijing 100044China China Academy of Space Technology Beijing 100094China

The footpad structure of a deep space exploration lander is a critical system that makes the initial contact with the ground,and thereby plays a crucial role in determining the stability and energy absorption characteristics during the impact *** conventional footpad is typically designed with an aluminum honeycomb structure that dissipates energy through plastic ***,its effectiveness in providing cushioning and energy absorption becomes significantly compromised when the structure is crushed,rendering it unusable for reusable landers in the *** study presents a methodology for designing and evaluating structural energy absorption systems incorporating recoverable strain constraints of shape memory alloys(SMA).The topological configuration of the energy absorbing structure is derived using an equivalent static load method(ESL),and three lightweight footpad designs featuring honeycomb-like Ni-Ti shape memory alloys structures and having variable stiffness skins are *** verify the accuracy of the numerical modelling,a honeycomb-like structure subjected to compression load is modeled and then compared with experimental ***,the influence of the configurations and thickness distribution of the proposed structures on their energy absorption performance is comprehensively evaluated using finite element *** results demonstrate that the proposed design approach effectively regulates the strain threshold to maintain the SMA within the constraint of maximum recoverable strain,resulting in a structural energy absorption capacity of 362 J/kg with a crushing force efficiency greater than 63%.

关键词： Deep space exploration lander Footpad Shape memory alloy(SMA) Reusable energy absorption structure Design method

Solvents incubatedπ-πstacking in hole transport layer for perovskite-silicon 2-terminal tandem solar cells with 27.21%efficiency

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Journal of Energy Chemistry 2023年第7期82卷 25-30,I0002页

作者： Qiaoyan Ma Jufeng qiu Yuzhao Yang Fei Tang Yilin Zeng Nanxi Ma Bohao Yu Feiping Lu Chong Liu Andreas Lambertz weiyuan Duan Kaining Ding Yaohua Mai Institute of New Energy Technology College of Information Science and TechnologyJinan UniversityGuangzhou 510632GuangdongChina School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006GuangdongChina IEK-5 Photovoltaik Forschungszentrum Jülich GmbH52425 JülichGermany Department of Physics Tianshui Normal UniversityTianshui 741000GansuChina Guangdong Mellow Energy Co. LimitedHuajing RoadGuangzhou 510630GuangdongChina

Room temperature sputtered inorganic nickel oxide(NiO_(x))is one of the most promising hole transport layers(HTL)for perovskite-sillion 2-terminal tandem solar cells with the aid of ultrathin and compact organic layers to passivate the surface *** this study,the aromatic solvent with different substituent groups was used to regulate the conformation of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)am ine](PTAA)*** a result,the single-junction perovskite solar cell(PSC)gained a power conversion efficiency(PCE)of 20.63%,contributing to a 27.21%efficiency for monolithic perovskite/silicon(double-side polished)2-terminal tandem solar cell,by applying the alkyl aromatic solvent to enhance theπ-πstacking of PTAA molecular *** tandem solar cell can maintain 95%initial efficiency after aging over 1000 *** study provides a universal approach for improving the photovoltaic performance of NiO_(x)/polymer-based perovskite/silicon tandem solar cells and other single junction inverted PSCs.

关键词： Tandem solar cells Low temperature deposition Hole transporting property π-πstacking Alkyl aromatic solvent