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THE DISTANCE BETWEEN DIFFERENT COMPONENTS OF THE UNIVERSAL TEICHMULLER SPACE

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Chinese Annals of Mathematics,Series B 2005年第4期26卷 537-542页

作者： WANG zhe School of Mathematical Sciences Fudan University Shanghai 200433 China.

The model of the universal Teichmuller union of infinite disconnected components. between different components is 0, and the every other component is 2. space by the derivatives of logarithm is the In this paper, it i... 详细信息

关键词： Universal Teichmuller space Logarithmic derivative Quasiconformal extension

SVC Video Transmission Optimization Algorithm in Software Defined Network

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China Communications 2018年第10期15卷 143-149页

作者： zhe Liu Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences

Scalable video coding(SVC) is a powerful tool to solve the network heterogeneity and terminal diversity in video applications. However, in related works about the optimization of SVC-based video streaming over Software Defined Network(SDN), most of the them are focused either on the number of transmission layers or on the optimization of transmission path for specific layer. In this paper, we propose a noval optimization algorithm for SVC to dynamically adjust the number of layers and optimize the transmission paths simultaneously. We establish the problem model based on the 0/1 knapsack model, and then solve it with Artificial Fish Swarm Algorithm. Additionally, the simulations are carried out on the Mininet platform, which show that our approach can dynamically adjust the number of layers and select the optimal paths at the same time. As a result, it can achieve an effective allocation of network resources which mitigates the congestion and reduces the loss of non-SVC stream.

关键词： SVC SDN OpenFlow Mininet Artificial Fish Swarm Algorithm (AFSA) 0/1 knapsack model

不同干细胞来源外泌体及其携非编码RNA诊疗骨性关节炎

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中国组织工程研究 2025年第19期29卷 4122-4131页

作者：王喆齐岩松徐永胜内蒙古自治区人民医院骨科中心(运动医学中心) 内蒙古自治区呼和浩特市010017

背景:外泌体可在骨性关节炎患者滑液和血浆中检测出来,其水平随着骨性关节炎的进展而不断变化,并且可以对骨性关节炎的局部炎症、软骨钙化和关节退化起缓解作用。目的:旨在全面了解不同干细胞来源外泌体在骨性关节炎诊疗中的作用和机制... 详细信息

背景:外泌体可在骨性关节炎患者滑液和血浆中检测出来,其水平随着骨性关节炎的进展而不断变化,并且可以对骨性关节炎的局部炎症、软骨钙化和关节退化起缓解作用。目的:旨在全面了解不同干细胞来源外泌体在骨性关节炎诊疗中的作用和机制,并提出了外泌体治疗骨性关节炎的前景和挑战。方法:检索PubMed及中国知网数据库,英文检索词为“exosomes,osteoarthritis,mesenchymal stem cells,stem cells”,中文检索词为“外泌体,骨性关节炎,间充质干细胞,干细胞”,对2003年10月至2023年10月发表的文献进行检索,最终纳入99篇文献进行综述。结果与结论:外泌体的出现给骨性关节炎的诊断和治疗带来了希望。外泌体内含RNA、蛋白质及脂类的差异能够作为骨性关节炎的生物标志物用于诊断。同时,来自不同干细胞的外泌体均能够有效保护软骨细胞、缓解炎症、维持软骨基质代谢以及调节血管生成和软骨下骨重塑,表现出治疗骨性关节炎的优秀潜力。工程化外泌体则突破传统局限,通过调节特定非编码RNA表达增强治疗特异性与效率,为骨性关节炎的治疗提供新策略。

关键词：外泌体骨性关节炎间充质干细胞干细胞软骨修复软骨再生软骨细胞 RNA 工程化外泌体

Entanglement Concentration with Different Measurement in a 3-Mode Optomechanical System

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Communications in Theoretical Physics 2017年第7期67卷 57-63页

作者： zhe Li School of Physics University of Chinese Academy of Sciences P.O. Box 4588 Beijing 100049 China

In this work, we perform a series of phonon counting measurement with different methods in a 3-mode optomechanical system, and we compare the difference of the entanglement after measurement. In this article we focus on the three eases： prefect measurement, imperfect measurement and on-off measurement. We find that whatever measurement you take, the entanglement will increase. The size of entanglement enhancement is the largest in the perfect measurement, second in the imperfect measurement, and it is not obvious in the on-off measurement. We are sure that the more precise measurement information, the larger entanglement concentration.

关键词： entanglement concentration quantum measurement optomechanical system

High-efficiency and pollution-controlling in-situ gasification chemical looping combustion system by using CO_2 instead of steam as gasification agent

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Chinese Journal of Chemical Engineering 2018年第11期26卷 2368-2376页

作者： zhe Shen Zhiyu Huang State Key Laboratory of Oil and Gas Reservoir Geology and Exploration Southwest Petroleum University School of Energy and Architecture Xi'an Aeronautical University

Using CO_2 as gasification agent instead of steam in in-situ coal gasification chemical looping combustion(i G-CLC)power plant can eliminate energy consumption for steam generation, thus obtaining higher system efficiency. In this work, a comparative study of iG-CLC power plant using steam and CO_2 as gasification agent is concentrated on. The effects of steam to carbon ratio(S/C) and CO_2 to carbon ratio(CO_2/C) on the fuel reactor temperature,char conversion, syngas composition and CO_2 capture efficiency are separately investigated. An equilibrium carbon conversion of 88.9% is achieved in steam-based case as S/C ratio increases from 0.7 to 1.1, whereas a maximum conversion of 84.2% is obtained in CO_2-based case with CO_2/C ranging from 0.7 to 1.1. Furthermore the effects of oxygen carrier to fuel ratio(φ) on system performances are investigated. Increasing φ from 1.0 to1.4 helps to achieve char conversion from 75.9% to 88.9% in steam-based case, by contrast the char conversion can achieve 66.3%–84.2% in CO_2-based case within the same φ range. In terms of iG-CLC power plant, recycling partial CO_2 to the fuel reactor improves the overall performance. Approximately 3.9% of net power efficiency are increased in CO_2-based plant, from steam-based plant. Higher CO_2 capture efficiency and lower CO_2 emission rate are observed in CO_2-gasified iG-CLC power plant, expecting to be 90.63% and 85.18 kg·MW-1·h-1,respectively.

关键词： CO2 Steam iG-CLC Comparative study

Quantitative Damage Detection for Planetary Gear Sets Based on Physical Models

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 190-196页

作者： CHENG zhe HU Niaoqing Institute of Mechatronics Engineering National University of Defense TechnologyChangsha 410073China

Planetary gear set is the critical component in helicopter transmission train, and an important problem in condition monitoring and health management of planetary gear set is quantitative damage detection. In order to resolve this problem, an approach based on physical models is presented to detect damage quantitatively in planetary gear set. A particular emphasis is put on a feature generation and selection method, which is used for sun gear tooth breakage damage detection quantitatively in planetary gear box of helicopter transmission system. In this feature generation procedure, the pure torsional dynamical models of 2K-H planetary gear set is established for healthy case and sun gear tooth-breakage case. Then, a feature based on the spectrum of simulation signals of the dynamical models is generated. Aiming at selecting the best feature suitable for quantitative damage detection, a two-sample Z-test procedure is used to analyze the performance of features on damage evolution tracing. A feature named SR, which had better performance in tracking damage, is proposed to detect damage in planetary gear set. Meanwhile, the sun gear tooth-chipped seeded experiments with different severity are designed to validate the method above, and then the test vibration signal is picked up and used for damage detection. With the results of several experiments for quantitative damage detection, the feasibility and the effect of this approach are verified. The proposed method can supply an effective tool for degradation state identification in condition monitoring and health management of helicopter transmission system.

关键词： planetary gear sets physical model quantitative detection feature extraction feature selection

Improved Oustaloup approximation of fractional-order operators using adaptive chaotic particle swarm optimization

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Journal of Systems Engineering and Electronics 2012年第1期23卷 145-153页

作者： zhe Gao Xiaozhong Liao School of Automation Beijing Institute of Technology Beijing 100081 P. R. China

A rational approximation method of the fractional-order derivative and integral operators is proposed. The turning fre- quency points are fixed in each frequency interval in the standard Oustaloup approximation. In the improved Oustaloup method, the turning frequency points are determined by the adaptive chaotic particle swarm optimization （PSO）. The average velocity is proposed to reduce the iterations of the PSO. The chaotic search scheme is combined to reduce the opportunity of the premature phenomenon. Two fitness functions are given to minimize the zero-pole and amplitude-phase frequency errors for the underlying optimization problems. Some numerical examples are compared to demonstrate the effectiveness and accuracy of this proposed rational approximation method.

关键词： fractional-order calculus rational approximation particle swarm optimization (PSO) tent map.

Dynamic Protective Control Strategy for Distributed Generation System with Fixed-speed Wind Turbines

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电力系统自动化 2012年第8期36卷 178-184页

作者： Mu WEI zhe CHEN Department of Energy Technology Aalborg UniversityAalborg 9220Denmark

The characteristics of induction generator based fixed-speed wind turbines(FSWT)are *** impacts of different execution time in protective operations are studied under different fault duration and various wind velocity situations,e.g.,FSWT stabilities of load shedding in distribution *** on this research,a dynamic protective control strategy for a distributed generation system(DGS)with FSWT is ***,simulation results demonstrate the effectiveness of the strategy.

关键词：分布式发电系统控制策略动态保护风力发电机组速度执行时间风力涡轮机异步发电机

双轴应变对NbSe_(2)/MoSi_(2)N_(4)肖特基势垒的调控

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原子与分子物理学报 2025年第5期42卷 182-188页

作者：张宇哲安梦雅谢泉贵州大学大数据与信息工程学院新型光电子材料与技术研究所贵阳550025

最近一种高质量的二维(Two-dimensional,2D)半导体材料MoSi_(2)N_(4)(MSN)在实验上被成功合成,具有优异的电气和机械性能.尽管最近有大量的研究致力于揭示MSN的材料特性,但到目前为止,对MSN的电接触物理特性的探索还比较少.在这项工作中... 详细信息

最近一种高质量的二维(Two-dimensional,2D)半导体材料MoSi_(2)N_(4)(MSN)在实验上被成功合成,具有优异的电气和机械性能.尽管最近有大量的研究致力于揭示MSN的材料特性,但到目前为止,对MSN的电接触物理特性的探索还比较少.在这项工作中,构建了金属-半导体NbSe_(2)/MSN肖特基结并使用第一性原理密度泛函理论计算研究了该肖特基结的材料特性.发现NbSe_(2)/MSN接触具有超低肖特基势垒高度(Schottky barrier height,SBH),这有利于纳米电子学应用.SBH可以通过施加双轴应变的方式进行有效的调控.当施加拉伸应变时能实现NbSe_(2)/MSN肖特基结由p型肖特基接触转变为p型欧姆接触,而当施加较大的压缩应变时能实现p型肖特基接触和n型肖特基接触之间的转换.我们的研究结果为MSN的2D电触点的物理特性提供了见解,并将为设计基于MSN的2D纳米器件的高性能电触点提供关键的一步.

关键词： MoSi_(2)N_(4) NbSe_(2) 肖特基结欧姆接触