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AREA INTEGRAL FUNCTIONS FOR SECTORIAL OPERATORS ON L^p SPACES 被引量:1
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作者 陈泽乾 孙牧 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期739-747,共9页
Area integral functions are introduced for sectorial operators on L^p-spaces. We establish the equivalence between the square and area integral functions for sectorial operators on L^p spaces. This follows that the re... Area integral functions are introduced for sectorial operators on L^p-spaces. We establish the equivalence between the square and area integral functions for sectorial operators on L^p spaces. This follows that the results of Cowling, Doust, McIntosh, Yagi, and Le Merdy on H^∞ functional calculus of seetorial operators on LP-spaces hold true when the square functions are replaced by the area integral functions. 展开更多
关键词 Sectorial operator H^∞ Functional calculus area integral function square function L^p space
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日间LED曝光干预对电竞青训员睡眠情况影响研究
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作者 周钰博 严永红 《照明工程学报》 2024年第3期16-21,共6页
近年来,电竞作为新兴体育运动全球迅猛发展,电竞选手和青训员数量大幅增加。然而,为了更好的视觉体验和功效,白天电竞训练常在低亮度环境(水平照度<200 lx)下进行,导致青训员缺乏足够光照刺激,易引发内分泌紊乱、昼夜节律紊乱、睡眠... 近年来,电竞作为新兴体育运动全球迅猛发展,电竞选手和青训员数量大幅增加。然而,为了更好的视觉体验和功效,白天电竞训练常在低亮度环境(水平照度<200 lx)下进行,导致青训员缺乏足够光照刺激,易引发内分泌紊乱、昼夜节律紊乱、睡眠质量下降,以及视疲劳和注意力下降等问题。目前,关于光照强度、光谱、时间和持续时长对昼夜节律等非视觉效应的研究主要集中在医疗和办公空间,缺乏对电竞训练空间的研究。因此,本文以电竞青训员和训练空间光环境为研究对象,从改善电竞训练运动员视疲劳、昼夜节律、睡眠质量出发,在调查了解电竞训练空间光环境现状与电竞青训员训练作息安排、视疲劳和睡眠质量等情况的基础上,通过对比实验探究基于节律健康角度设置的训练作息适应性曝光模式对电竞青训员视疲劳缓解、注意力、睡眠质量改善的可能性。 展开更多
关键词 电竞训练空间光环境 曝光 动态照明 视疲劳 节律健康 睡眠质量
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E波段连续波空间行波管研制进展 被引量:1
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作者 李志良 李梦园 +3 位作者 梁文龙 李安 梁晓峰 瞿波 《太赫兹科学与电子信息学报》 2023年第10期1194-1197,1203,共5页
针对高波段空间行波管的卫星通信应用需求,介绍了E波段连续波空间行波管的研制情况。该行波管通过进一步优化折叠波导慢波结构参数和调整周期跳变方案,实现改善带内增益波动性、提高效率的目的。研制出的样管在14.7 kV、74 mA条件下,实... 针对高波段空间行波管的卫星通信应用需求,介绍了E波段连续波空间行波管的研制情况。该行波管通过进一步优化折叠波导慢波结构参数和调整周期跳变方案,实现改善带内增益波动性、提高效率的目的。研制出的样管在14.7 kV、74 mA条件下,实现电子注动态流通率高于98%,在71~76 GHz范围内,输出功率大于85 W,总效率大于37%,增益大于40 dB。 展开更多
关键词 e波段 折叠波导 连续波 空间行波管
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E波段空间行波管盒型窗设计与实验 被引量:1
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作者 李志良 李梦园 +1 位作者 史国强 梁文龙 《真空电子技术》 2023年第2期16-19,共4页
根据空间通信发展需要对E波段空间行波管输能窗进行研究。窗片的材料选择金刚石,通过菲涅尔理论分析得到无反射盒型输出窗片的关键尺寸,并利用CST软件进行计算和优化,获得适合E波段空间行波管需求的输能窗。通过磁控溅射金属化窗片,封... 根据空间通信发展需要对E波段空间行波管输能窗进行研究。窗片的材料选择金刚石,通过菲涅尔理论分析得到无反射盒型输出窗片的关键尺寸,并利用CST软件进行计算和优化,获得适合E波段空间行波管需求的输能窗。通过磁控溅射金属化窗片,封接出气密性良好的输能窗。测试结果表明,该窗在60~87 GHz频段内驻波系数低于1.1。 展开更多
关键词 空间行波管 e波段 盒型窗 金刚石
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Characterizations of Sobolev spaces in Euclidean spaces and Heisenberg groups 被引量:3
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作者 CUI Xiao-yue LAM Nguyen LU Guo-zhen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第4期531-547,共17页
Recently, many new features of Sobolev spaces W k,p ?RN ? were studied in [4-6, 32]. This paper is devoted to giving a brief review of some known characterizations of Sobolev spaces in Euclidean spaces and describin... Recently, many new features of Sobolev spaces W k,p ?RN ? were studied in [4-6, 32]. This paper is devoted to giving a brief review of some known characterizations of Sobolev spaces in Euclidean spaces and describing our recent study of new characterizations of Sobolev spaces on both Heisenberg groups and Euclidean spaces obtained in [12] and [13] and outlining their proofs. Our results extend those characterizations of first order Sobolev spaces in [32] to the Heisenberg group setting. Moreover, our theorems also provide diff erent characterizations for the second order Sobolev spaces in Euclidean spaces from those in [4, 5]. 展开更多
关键词 characterization of Sobelev spaces Folland-Stein space Poincar′e inequalities Heisenberg group second order Sobolev space
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论CiteSpace在外国语言文字领域的应用现状——基于CSSCI来源期刊文献的数据分析 被引量:1
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作者 刘静 《四川职业技术学院学报》 2017年第3期73-77,共5页
外国语言文字领域对CiteSpace的使用呈现出起步晚、数量少的特点,发文量总体保持上升势头。CiteSpace在外国语言文字领域的应用可划分为六大领域,翻译领域的使用最多。王立非教授是该领域的高产作者,《外语电化教学》尤其青睐此类文章... 外国语言文字领域对CiteSpace的使用呈现出起步晚、数量少的特点,发文量总体保持上升势头。CiteSpace在外国语言文字领域的应用可划分为六大领域,翻译领域的使用最多。王立非教授是该领域的高产作者,《外语电化教学》尤其青睐此类文章。北京、上海和南京是CiteSpace在外国语言文字领域应用传播的三大"重镇",其中北京居首。外国语言文字领域对CiteSpace的应用没有跟上软件更新的步伐且忽视了与同类其他可视化软件的结合,实践者对CiteSpace经典文献的知识掌握不足。 展开更多
关键词 CIT e space CSSCI 外国语言文字 应用现状 趋势
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Common Fixed Point Theorems for Compatible and Weakly Compatible Maps in G-Metric Spaces 被引量:1
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作者 Asha Rani Sanjay Kumar +1 位作者 Naresh Kumar S. K. Garg 《Applied Mathematics》 2012年第10期1128-1134,共7页
In this paper first we prove common fixed point theorems for compatible and weakly compatible maps. Secondly, we prove common fixed point theorems for weakly compatible maps along with property (E.A.) and (CLRg) prope... In this paper first we prove common fixed point theorems for compatible and weakly compatible maps. Secondly, we prove common fixed point theorems for weakly compatible maps along with property (E.A.) and (CLRg) property respectively. 展开更多
关键词 G-metric spaceS Compatible MAPS WeAKLY Compatible MAPS PROPeRTY (e.A.) (CLRg) PROPeRTY
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Common Fixed Point Theorems for Weakly Compatible Mappings in Fuzzy Metric Spaces Using (JCLR) Property 被引量:1
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作者 Sunny Chauhan Wutiphol Sintunavarat Poom Kumam 《Applied Mathematics》 2012年第9期976-982,共7页
In this paper, we prove a common fixed point theorem for a pair of weakly compatible mappings in fuzzy metric space using the joint common limit in the range property of mappings called (JCLR) property. An example is ... In this paper, we prove a common fixed point theorem for a pair of weakly compatible mappings in fuzzy metric space using the joint common limit in the range property of mappings called (JCLR) property. An example is also furnished which demonstrates the validity of main result. We also extend our main result to two finite families of self mappings. Our results improve and generalize results of Cho et al. [Y. J. Cho, S. Sedghi and N. Shobe, “Generalized fixed point theorems for compatible mappings with some types in fuzzy metric spaces,” Chaos, Solitons & Fractals, Vol. 39, No. 5, 2009, pp. 2233-2244.] and several known results existing in the literature. 展开更多
关键词 Fuzzy Metric space WeAKLY Compatible MAPPINGS (e.A) PROPeRTY (CLR) PROPeRTY (JCLR) PROPeRTY
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Crystallography in the Spaces E<sup>2</sup>, E<sup>3</sup>, E<sup>4</sup>, E<sup>5</sup>...N<sup>0</sup>II Isomorphism Classes and Study of Five Crystal Families of Space E<sup>5</sup> 被引量:1
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作者 R. Veysseyre D. Weigel +1 位作者 T. Phan H. Veysseyre 《Advances in Pure Mathematics》 2015年第4期196-207,共12页
In the paper N0II, we describe some isomorphism classes and we apply their properties to the study of five crystal families of space E5. The names of these families are the following ones (monoclinic di iso squares)-a... In the paper N0II, we describe some isomorphism classes and we apply their properties to the study of five crystal families of space E5. The names of these families are the following ones (monoclinic di iso squares)-al, decadic-al, (monoclinic di iso hexagons)-al, (rhombotopic cosa=-1/4)-al and rhombotopic cosa=-1/5. The meaning of these names will be given in Paragraphs 5 and 6 with some geometric properties of their cell. 展开更多
关键词 CRYSTAL Families of space e5 NAMeS Point Groups of the Families Rhombotopic CRYSTAL Families
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FREDHOLM OPERATORS ON THE SPACE OF BOUNDED SEQUENCES
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作者 Egor A.ALEKHNO 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期614-634,共21页
Necessary and sufficient conditions are studied that a bounded operator Tx =(x1^*x, x2^*x,…) on the space e∞, where xn^*∈e∞^*, is lower or upper semi-Fredholm; in particular, topological properties of the se... Necessary and sufficient conditions are studied that a bounded operator Tx =(x1^*x, x2^*x,…) on the space e∞, where xn^*∈e∞^*, is lower or upper semi-Fredholm; in particular, topological properties of the set {x1^*, x2^* …} are investigated. Various estimates of the defect d(T) = codim R(T), where R(T) is the range of T, are given. The case of xn^* = dnxtn^*,where dn ∈ R and xtn^* 〉 0 are extreme points of the unit ball Be∞^*, that is, tn ∈ βN, is considered. In terms of the sequence {tn}, the conditions of the closedness of the range R(T) are given and the value d(T) is calculated. For example, the condition {n : 0 〈 |da| 〈 δ}= θ for some 5 is sufficient and if for large n points tn are isolated elements of the sequence {tn}, then it is also necessary for the closedness of R(T) (tn0 is isolated if there is a neighborhood U of tno satisfying tn ∈ U for all n ≠ n0). If {n : |dn| 〈 δ} = θ, then d(T) is equal to the defect δ{tn} of {tn}. It is shown that if d(T) = ∞ and R(T) is closed, then there exists a sequence {An} of pairwise disjoint subsets of N satisfying XAn ∈ R(T). 展开更多
关键词 Fredholm operator space e Stone-Cech compactification βN
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A Note on Pad Approximants Pairs as Limits of Algebraic Polynomials Pairs of Weighted Best Approximation in Orlicz Spaces
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作者 F.E.Levis 《Analysis in Theory and Applications》 CSCD 2015年第3期253-259,共7页
In this short note, we show the behavior in Orlicz spaces of best approximations by algebraic polynomials pairs on union of neighborhoods, when the measure of them tends to zero.
关键词 Best approximation pair Pad′e approximant pair Orlicz spaces.
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Development of Operational Space Environment Technology System 被引量:1
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作者 GONG Jiancun CAI Yanxia +4 位作者 LIU Siqing SHI Liqin LU Guorui CHEN Zhaofeng BAO Lili 《空间科学学报》 CAS CSCD 北大核心 2016年第5期753-761,共9页
With the increasing of users and the demands which are transforming from the monotonous traditional service to network service,Multiple space environment web applications including browser-client,rich-client and mobil... With the increasing of users and the demands which are transforming from the monotonous traditional service to network service,Multiple space environment web applications including browser-client,rich-client and mobile-client applications have been developed by SEPC(Space Environment Prediction Center,NSSC,CAS)during the past few years.The architecture of Operational Space Environment Technology System(OSETS) that these applications rely on is described and the description of structural optimization of the architecture is provided.To demonstrate the evolution of the OSETS,three web application examples for e SpaceWx,Space Weather Situation Awareness Picture(SWSAP),Plug-and-Play SWx Analysis and Plotting Program(PPSWAP) are presented. 展开更多
关键词 空间环境预报 技术系统 作战空间 开发 WeB应用程序 客户端应用程序 网络服务 环境技术
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NEWTON-LIK E METNODS IN PARTIALLY ORDERED BANACH SPACES
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作者 I.K.Argyros 《Analysis in Theory and Applications》 1993年第1期1-9,共9页
We provide convergence results and error estimates for Newton-like methods in generalized Banach spaces.The idea of a generalized norm is used whichis defined to be a map from a linear space into a partially ordered B... We provide convergence results and error estimates for Newton-like methods in generalized Banach spaces.The idea of a generalized norm is used whichis defined to be a map from a linear space into a partially ordered Banach space.Convergence results and error estimates are improved compared with the real norm theory. 展开更多
关键词 SHOW QZ NeWTON-LIK e MeTNODS IN PARTIALLY ORDeReD BANACH spaceS
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<i>E</i>Infinity, the Zero Set, Absolute Space and the Photon Spin
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作者 Jean-Paul Auffray 《Journal of Modern Physics》 2015年第5期536-545,共10页
As defined and used in General Relativity calculations, spacetime is a strictly classical construct which does not incorporate in any way, shape or form the concept of quantum. While reviewing the efforts that Alexand... As defined and used in General Relativity calculations, spacetime is a strictly classical construct which does not incorporate in any way, shape or form the concept of quantum. While reviewing the efforts that Alexandria theoretician M. S. El Naschie has made to resolve the dichotomy, we discovered that his E infinity theory contains a Cantor set which has characteristics specified by Isaac Newton for Absolute space. We show that this unexpected connection leads to an understanding of the mysterious origin of the one and only attribute that all particles listed in the Standard Model of Elementary Particles possess—including notably the photon—and which has remained unexplained hitherto: spin. This most rewarding result reinforces our belief in the relevance of the E infinity basic concepts in relation to our own Xonic Quantum Physics (XQP) which places dynamical action rather spacetime and energy at the core of the System of the World. 展开更多
关键词 QUANTUM Foam e INFINITY Xonic QUANTUM Physics Newton ABSOLUTe space PHOTON SPIN
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E-Infinity Dualities, Discontinuous Spacetimes, Xonic Quantum Physics and the Decisive Experiment 被引量:2
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作者 Jean-Paul Auffray 《Journal of Modern Physics》 2014年第15期1427-1436,共10页
Using powerful concepts and tools borrowed from the seminal arsenal connecting physics fundamentals with esoteric set theoretical operations developed in recent years by Alexandria E-infinity theoretician M. S. El Nas... Using powerful concepts and tools borrowed from the seminal arsenal connecting physics fundamentals with esoteric set theoretical operations developed in recent years by Alexandria E-infinity theoretician M. S. El Naschie, this paper explores the deep implications of some of the dualities Dr El Naschie has identified and analyzed in his exposes, connecting them with our own Xonic Quantum Physics (XQP) which places dynamical action rather than spacetime and energy at the core of the System of the World. 展开更多
关键词 e-INFINITY el Naschie space Time spaceTIMe Topology CANTOR Sets energy Xon Xonic Quantum Physics PLANCK Scale Dirac electron
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FIXED POINT THEOREMS OF LOCAL CONTRACTION MAPPINGS ON MENGER SPACES
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作者 方锦暄 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第4期363-372,共10页
In this paper,we introduce the concept ofε-chainable PM-space,and give severalfixed point theorems of one-valued and multivalued local contraction mapping on the kindof spaces.
关键词 probabilistic metric space Menger space e-chainable local contraction mapping fixed point
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Completing Einstein’s Spacetime 被引量:3
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作者 M. S. El Naschie 《Journal of Modern Physics》 2016年第15期1972-1994,共24页
The four-dimensional character of Einstein’s spacetime is generally accepted in mainstream physics as beyond reasonable doubt correct. However the real problem is when we require scale invariance and that this spacet... The four-dimensional character of Einstein’s spacetime is generally accepted in mainstream physics as beyond reasonable doubt correct. However the real problem is when we require scale invariance and that this spacetime be four-dimensional on all scales. It is true that on our classical scale, the 4D decouples into 3D plus one time dimension and that on very large scale only the curvature of spacetime becomes noticeable. However the critical problem is that such spacetime must remain 4D no matter how small the scale we are probing is. This is something of crucial importance for quantum physics. The present work addresses this basic, natural and logical requirement and shows how many contradictory results and shortcomings of relativity and quantum gravity could be eliminated when we “complete” Einstein’s spacetime in such a geometrical gauge invariant way. Concurrently the work serves also as a review of the vast Literature on E-Infinity theory used here. 展开更多
关键词 e-INFINITY Cantorian spacetime SeLF-SIMILARITY M-THeORY Kaluza-Klein space Fuzzy Kähler Manifolds Continued Fraction Isomorphic Length Geometrical Gauge Invariance
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Virtual Education Space
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作者 Vladimir Valkanov Stanimir Stoyanov Veselina Valkanova 《通讯和计算机(中英文版)》 2016年第2期64-76,共13页
关键词 空间问题 教育领域 虚拟环境 社会系统 教学内容 教育服务 教育过程 保加利亚
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基于Cite Space的国外电子竞技研究进展与趋势分析
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作者 孙泽峰 《体育科技文献通报》 2022年第4期225-227,共3页
电子竞技近年来发展迅速,已经成为亚运会的正式项目,在国际上具有一定的影响力。本文使用Cite Space软件,对Web of Science收录的2006年-2022年以“esports”为主要关键词的文献进行可视化分析。其中包括文献的基本情况分析、共被引分... 电子竞技近年来发展迅速,已经成为亚运会的正式项目,在国际上具有一定的影响力。本文使用Cite Space软件,对Web of Science收录的2006年-2022年以“esports”为主要关键词的文献进行可视化分析。其中包括文献的基本情况分析、共被引分析、关键词分析,展示了目前国际电子竞技的研究热点,对中国学者对电子竞技的研究具有一定的参考作用。 展开更多
关键词 电子竞技 综述 cite space 国外研究
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月球样品的中子活化分析技术研究 被引量:8
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作者 姚永刚 肖才锦 +4 位作者 李玉庆 焦学胜 孙凯 郭冰 陈东风 《中国无机分析化学》 CAS 北大核心 2024年第1期93-103,共11页
月球的起源是月球研究的核心问题。月球探测任务返回的数据和样品极大地提高了人类对地月系统的认知,同时也发现了更多未解之谜,亟待未来的探测任务和科学研究来解答。嫦娥五号月壤是我国首次地外天体采集返回的样品,也是继美国和苏联... 月球的起源是月球研究的核心问题。月球探测任务返回的数据和样品极大地提高了人类对地月系统的认知,同时也发现了更多未解之谜,亟待未来的探测任务和科学研究来解答。嫦娥五号月壤是我国首次地外天体采集返回的样品,也是继美国和苏联探月采样任务45年后人类再次获得的月球样品。鉴于月球样品的珍贵性和特殊性,利用先进技术开展其全元素含量的非破坏精准分析对于认识月球演化和月球资源就地开发利用具有重要的意义。依托大型核反应研究堆和加速器中子注量率优势,利用中子活化分析技术可实现月球样品中的全元素非破坏分析:1)仪器中子活化分析技术(INAA)可测量Na—U元素之间的60余种元素;2)瞬发γ中子活化分析技术(PGNAA)可补充测量INAA不适合测量的元素如H、B、C、N等;3)中子深度剖面分析技术(NDP)可测量样品近表面(微米级)聚变能源3He的浓度深度分布;4)缓发中子测量技术(DNC)可定量样品中痕量裂变核素如^(235)U和^(239)Pu,并结合INAA可测量238U/235U同位素比值;5)14 MeV快中子活化分析技术(FNAA)可测量INAA和PGNAA不灵敏或不适合测量的元素如O、Si、P等。因此,中子活化分析技术(NAA)可有效解决月球样品中全元素、非破坏和精准测量问题,为我国深空探测珍贵样品研究提供核分析技术支撑。 展开更多
关键词 嫦娥五号月壤 月球陨石 中子活化分析 非破坏分析 深空探测
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