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益气健心汤联合艾灸治疗慢性心力衰竭临床研究

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光明中医 2024年第7期39卷 1349-1352页

作者：张朝辉东明县中医医院老年病科山东菏泽274500

目的分析益气健心汤联合艾灸在慢性心力衰竭(CHF)患者中的治疗效果。方法选取2021年1月—2023年1月东明县中医医院收治的96例CHF患者,按随机数字表法分为2组,各48例。对照组给予常规西医治疗,观察组加用益气健心汤联合艾灸治疗。对比... 详细信息

目的分析益气健心汤联合艾灸在慢性心力衰竭(CHF)患者中的治疗效果。方法选取2021年1月—2023年1月东明县中医医院收治的96例CHF患者,按随机数字表法分为2组,各48例。对照组给予常规西医治疗,观察组加用益气健心汤联合艾灸治疗。对比2组临床疗效、中医证候评分、心功能、不良反应。结果观察组治疗总有效率较对照组高,且各项中医证候评分较对照组低,各项心功能指标较对照组优,差异有统计学意义(P0.05)。结论益气健心汤联合艾灸可减轻CHF患者临床症状,改善心功能,且无严重不良反应。

关键词：胸痹慢性心力衰竭益气健心汤艾灸疗法

中国城市群的发展测度:基于19个主要城市群

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区域经济评论 2024年第2期 100-110页

作者：董昕张朝辉刘晓霖中国社会科学院大学应用经济学院北京102488 中国社会科学院生态文明研究所生态城市研究室北京100710

中国城市群研究主要基于地理学的局部视角,而对经济社会发展的整体性考量不足,对中国城市群整体发展规律的把握也有所欠缺。基于对中国19个主要城市群经济社会发展指标的分析,从要素集聚度、发展活跃度与可持续性三方面总结中国城市群... 详细信息

中国城市群研究主要基于地理学的局部视角,而对经济社会发展的整体性考量不足,对中国城市群整体发展规律的把握也有所欠缺。基于对中国19个主要城市群经济社会发展指标的分析,从要素集聚度、发展活跃度与可持续性三方面总结中国城市群的整体发展状况,并利用熵权TOPSIS、Dagum基尼系数对各城市群的综合发展状况进行评价与分解。从总体上看,主要城市群在国民经济发展中占有绝对主体地位,但经济带动作用有所下降;从城市群之间的差异看,主要城市群的发展差异始终凸显,优化提升类城市群的发展水平远高于发展壮大类与培育发展类城市群,发展壮大类与培育发展类城市群间的差距相对较小;从城市群内部的差异看,主要城市群内部的发展水平差异很大,且城市群内中心城市的极化作用有所增强。

关键词：城市群要素集聚经济发展可持续差异分解

Dehn Twists and Products of Mapping Classes of Riemann Surfaces with One Puncture

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Chinese Annals of Mathematics,Series B 2011年第6期32卷 885-894页

作者： chaohui zhang Department of Mathematics Morehouse College Atlanta GA 30314 USA

Let S be a Riemann surface that contains one puncture x. Let be the collection of simple closed geodesics on S, and let denote the set of mapping classes on S isotopic to the identity on S U {x}. Denote by tc the positive Dehn twist about a curve c ∈ . In this paper, the author studies the products of forms （tb^-m o t^na） o f^k, where a, b ∈ and f ∈ . It is easy to see that if a = b or a, b are boundary components of an x-punctured cylinder on S, then one may find an element f ∈ such that the sequence （tb^-m o t^na） ofk contains infinitely many powers of Dehn twists. The author shows that the converse statement remains true, that is, if the sequence （tb^-m o t^na） o f^k contains infinitely many powers of Dehn twists, then a, b must be the boundary components of an x-punctured cylinder on S and f is a power of the spin map tb^-1 o ta.

关键词： Riemann surfaces Simple closed geodesics Dehn twists Products Bers isomorphisms

Hyperbolic Mapping Classes and Their Lifts on the Bers Fiber Space

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Chinese Annals of Mathematics,Series B 2007年第1期28卷 55-66页

作者： chaohui zhang Department of Mathematical Sciences Morehouse College Atlanta GA 30314 USA.

Let S be a Riemann surface with genus p and n punctures. Assume that 3p- 3 ＋ n 〉 0 and n 〉 1. Let a be a puncture of S and let S = S∪{α}. Then all mapping classes in the mapping class group Mods that fixes the puncture a can be projected to mapping classes of Mod$ under the forgetful map. In this paper the author studies the mapping classes in Mods that can be projected to a given hyperbolic mapping class in Mode.

关键词： Riemann surfaces Absolutely extremal Teichmüller mapping Mapping classes Teichmiiller spaces Bers fiber spaces

On Reduced Lantern Relations in Mapping Class Groups

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Chinese Annals of Mathematics,Series B 2014年第1期35卷 79-92页

作者： chaohui zhang Department of Mathematics Morehouse College

Let S be a hyperbolic Riemann surface with a finite area. Let G be the covering group of S acting on the hyperbolic plane H. In this paper, the author studies some algebraic relations in the mapping class group of S for S = S／{a point}. The author shows that the only possible relations between products of two Dehn twists and products of mapping classes determined by two parabolic elements of G are the reduced lantern relations. As a consequence, a partial solution to a problem posed by J. D. McCarthy is obtained.

关键词： Dehn twists Simple closed geodesics Lantern relation

Pseudo-Anosov Mapping Classes and Their Representations by Products of Two Dehn Twists

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Chinese Annals of Mathematics,Series B 2009年第3期30卷 281-292页

作者： chaohui zhang Department of Mathematics Morehouse College Atlanta GA 30314 USA

Let S be a Riemann surface of analytically finite type （p, n） with 3p-3＋n 〉 0. Let a ∈ S and S = S - {a}. In this article, the author studies those pseudo-Anosov maps on S that are isotopic to the identity on S and can be represented by products of Dehn twists. It is also proved that for any pseudo-Anosov map f of S isotopic to the identity on S, there are infinitely many pseudo-Anosov maps F on S - {b} = S - {a, b}, where b is a point on S, such that F is isotopic to f on S as b is filled in.

关键词： Riemann surface Pseudo-Anosov map Dehn twist Teichmullerspace Bers fiber space

Remarks on Thurston's Construction of Pseudo-Anosov Maps of Riemann Surfaces

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Chinese Annals of Mathematics,Series B 2008年第1期29卷 85-94页

作者： chaohui zhang Department of Mathematical Sciences Morehouse College Atlanta GA 30314 USA

It is well known that certain isotopy classes of oseudo-Anosov maos on a Riemann surface S of non-excluded type can be defined through Dehn twists tα and tβ along simple closed geodesics α and β on S,respectively. Let G be the corresponding Fuchsian group acting on the hyperbolic plane H so that H/G≌*** any point α∈S,define S = S／{α}.In this article, the author gives explicit parabolic elements of G from which he constructs pseudo-Anosov classes on S that can be projected to a given pseudo-Anosov class on S obtained from Thurston＇s construction.

关键词： Quasiconformal mappings Riemann surfaces Teichmüller spaces Mapping classes Dehn twists Pseudo-Anosov Bers fiber spaces

Material removal model for non-contact chemical mechanical polishing

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Chinese Science Bulletin 2008年第23期53卷 3746-3752页

作者： zhang JianQun zhang chaohui School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing 100044 China

Material removal mechanism under non-contact condition between the pad and the wafer in the chemical mechanical polishing (CMP) process is investigated. Based on the assumption that almost all effective material removals take place due to the active abrasives which cut material through the plowing effects. A novel model is developed to predict the material removal rate (MRR) under non-contact condition between the pad and the wafer in CMP. Validated by the experimental data, the model is proved to be able to predict the change of MRR under non-contact condition. Numerical simulation of the model shows: the relative velocity u between the pad and the wafer and fluid viscosity η are the most important factors which impact MRR under non-contact condition; load changes of wafer also affects the MRR, but the effect is not as obvious as the relative velocity and fluid viscosity; when the radius of abrasive is not less than 50nm, the impact of MRR alone with the changes in the size of the abrasive can be ignored.

关键词： CMP 非接触条件材料移动原理 MRR

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中草药图像识别分类模型的设计与实现

福建电脑 2024年第5期40卷 14-20页

作者：张超辉江燕戴杰玲广东茂名健康职业技术学院教育技术与网络中心广东茂名525400

中文中草药作为中医的重要组成部分,在治疗多种疾病中扮演着关键角色。由于许多中草药在视觉上极为相似,为应用深度学习对其进行分类识别,本文构建了一个中草药分类识别模型。该模型的构建采用残差神经网络结合卷积块注意模块,并应用融... 详细信息

中文中草药作为中医的重要组成部分,在治疗多种疾病中扮演着关键角色。由于许多中草药在视觉上极为相似,为应用深度学习对其进行分类识别,本文构建了一个中草药分类识别模型。该模型的构建采用残差神经网络结合卷积块注意模块,并应用融合局部二值模式特征以及迁移学习策略来提升模型的识别准确率。实验的结果表明,本文模型的准确率、召回率、精确度和F1分数分别达到96.88%、96.80%、96.87%和96.80%。

关键词：中草药残差神经网络分类识别模型