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Topology optimization of thermoelastic structures using the guide-weight method

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Science China(Technological Sciences) 2014年第5期57卷 968-979页

作者： LIU XinJun WANG Chao zhou yanhua State Key Laboratory of Tribology & Institute of Manufacturing Engineering Department of Mechanical Engineering Tsinghua University Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University Institute of Aircraft Engineering Naval Aeronautical and Astronautical University

The guide-weight method is introduced to solve the topology optimization problems of thermoelastic structures in this ***,the solid isotropic microstructure with penalization(SIMP)with different penalty factors is selected as a material interpolation model for the thermal and mechanical *** general criteria of the guide-weight method is then *** types of iteration formulas of the guide-weight method are applied to the topology optimization of thermoelastic structures,one of which is to minimize the mean compliance of the structure with material constraint,whereas the other one is to minimize the total weight with displacement *** each type of problem,sensitivity analysis is conducted based on SIMP ***,four classical 2-dimensional numerical examples and a 3-dimensional numerical example considering the thermal field are selected to perform *** factors that affect the optimal topology are discussed,and the performance of the guide-weight method is *** results show that the guide-weight method has the advantages of simple iterative formula,fast convergence and relatively clear topology result.

关键词： topology optimization thermoelastic guide-weight method sensitivity analysis

Error Modeling and Sensitivity Analysis of a Parallel Robot with SCARA(Selective Compliance Assembly Robot Arm) Motions

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 693-702页

作者： CHEN Yuzhen XIE Fugui LIU Xinjun zhou yanhua Department of Mechanical Engineering Tsinghua University Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University Institute of Aircraft Engineering Naval Aeronautical and Astronautical University

Parallel robots with SCARA（selective compliance assembly robot arm） motions are utilized widely in the field of high speed pick-and-place manipulation. Error modeling for these robots generally simplifies the parallelogram structures included by the robots as a link. As the established error model fails to reflect the error feature of the parallelogram structures, the effect of accuracy design and kinematic calibration based on the error model come to be undermined. An error modeling methodology is proposed to establish an error model of parallel robots with parallelogram structures. The error model can embody the geometric errors of all joints, including the joints of parallelogram structures. Thus it can contain more exhaustively the factors that reduce the accuracy of the robot. Based on the error model and some sensitivity indices defined in the sense of statistics, sensitivity analysis is carried out. Accordingly, some atlases are depicted to express each geometric error’s influence on the moving platform’s pose errors. From these atlases, the geometric errors that have greater impact on the accuracy of the moving platform are identified, and some sensitive areas where the pose errors of the moving platform are extremely sensitive to the geometric errors are also figured out. By taking into account the error factors which are generally neglected in all existing modeling methods, the proposed modeling method can thoroughly disclose the process of error transmission and enhance the efficacy of accuracy design and calibration.

关键词： parallel robot selective compliance assembly robot arm(SCARA) motions error modeling sensitivity analysis parallelogram structure

An efficient method for the sanitary vitrification of bovine oocytes in straws

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Journal of Animal Science and Biotechnology 2014年第4期5卷 399-405页

作者： yanhua zhou Xiangwei Fu Guangbin zhou Baoyu Jia Yi Fang Yunpeng Hou Shien Zhu National Engineering Laboratory for Animal Breeding Key Laboratory of Animal geneticsBreeding and ReproductionMinistry of AgricultureCollege of Animal Science and TechnologyChina Agricultural University Institute of Animal Genetics and Breeding College of Animal Science and TechnologySichuan Agricultural University(Chengdu Campus) State Key Laboratory for Agrobiotechnology College of Biological SciencesChina Agricultural University

Background：At present,vitrification has been widely applied to humans,mice and farm *** improve the efficiency of vitrification in straw,bovine oocytes were used to test a new two-step vitrification method in this ***：When in vitro matured oocytes were exposed to 20%ethylene glycol（EG20） for 5 min and 40%ethylene glycol（EG40） for 30 s,followed by treatment with 30%glycerol（Gly30）,Gly40 or Gly50,a volume expansion was observed in Gly30 and Gly40 but not *** indicates that the intracellular osmotic pressure after a 30 s differs between EG40 and ranged between Gly40（approximately 5.6 mol/L） and Gly50（approximately 7.0 mol/L）.Since oocytes are in EG40 just for only a short period of time（30 s） and at a lower temperature（4℃）,we hypothesize that the main function of this step in to induce *** on these results,we omitted the EG40 step,before oocytes were pretreated in EG20 for 5 min,exposed to pre-cooled（4℃） Gly50,for 30 s,and then dipped into liquid *** warming,81.1%of the oocytes survived,and the surviving oocytes developed into cleavage stage embryos（63.5%） or blastocysts（20.0%） after parthenogenetic ***：These results demonstrate that in a two-step vitrification procedure,the permeability effect in the second step is not *** is possible that the second step is only required to provide adequate osmotic pressure to condense the intracellular concentration of CPAs to a level required for successful vitrification.

关键词： Bovine Cryopreservation Oocytes Straw Vitrification

Clinical characteristics and treatments of cap polyposis:a single center case series

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Gastroenterology Report 2023年第1期11卷 554-556页

作者： yanhua zhou Rui Cheng Ningning Dong Ying Meng Chuntao Liu Ye Zong Department of Gastroenterology Beijing Friendship HospitalCapital Medical UniversityNational Clinical Research Center for Digestive DiseaseBeijingP.R.China

Introduction Cap polyposis is a rare benign disease of the digestive tract,characterized by inflammatory polyps with a cap of inflammatory granulation *** described in 1985 by Williams et al.[1],cap polyposis is now still introduced in case *** clinical course and pathogenesis of this disease are yet to be elucidated and specific therapies have not been established.

关键词： polyposis clinical

The influencing factors of urban land expansion in Changsha

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Journal of Geographical Sciences 2007年第4期17卷 487-499页

作者： zhou Guohua HE yanhua College of Science of Resource ＆ Environment Science Hunan Normal University Changsha 410081 China

This research systematically analyses land-use map of Changsha city in different periods of time. The spatial form and structural evolution was analysed by studying indices such as city land-use structure proportion, expansion intensity, economic flexibility, population flexibility, changing compactness index and so on. The dynamic mechanism of urban land expansion has been discussed by integrating the regional social economy development situation and many aspects such as the physiographical surrounding, population and economic development, traffic infrastructure, planning and regional development tactic and system innovation. The research indicates that the urban land expansion speed and intensity have steadily increased in Changsha from 1949 to 2004. The expansion form has been from a single external expansion to a combination form of external and internal expansion, from a circular or linear continuous form to a blocky or agglomeration shape. Overall, the urban land expansion of Changsha city is a phasic, diversified and complex process. And no matter what the stage is, it is an organic system containing multiple speed, pattern and shape, which are driven by multiple impetuses. The dominant feature at different stages was highlighted because of the balance and fluctuation between different forces, and the existing urban land border and shape have resulted from the joint efforts of these phasic forces.

关键词： Changsha urban land expansion influencing factors dynamic mechanism

Marxism in China and ideological education

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International Journal of Technology Management 2013年第11期 123-125页

作者： yanhua zhou Yuwang Peng Langfang Teachers University LangfangHebeiChina North China Institute of Aerospace Engineering Langfang Hebei China

It is a big project of whole society to strengthen the holistic view and ideological and political education, thus we must work together to make full use of social resources to advocate the basic value rules of society and guarantee the promotion of human nature, guiding people to think according to the social reality to enhance rational ability of thinking, eventually forming a mutual power of education; in the mean time, we should still exert advantages of strong systematic, theoretical and logical factors to achieve double swords with combination of education mode. Theoretical teaching plus beneficial activities, one-way teaching with activities and school education combined with social and media education can achieve socialization of ideological and political education. Drawing on the experience of other countries, we can constantly create new approach suitable to our national conditions and the requirements development and enhance the effectiveness of ideological and political education.

关键词： Marxism ideological education scientific development.

Effects of hyperbaric oxygen therapy on 32 cases of full-thickness skin grafting for the repair of defects on the hand and foot

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Discussion of Clinical Cases 2018年第3期5卷 28-30页

作者： yanhua zhou Dong Wang Department of Medical Oxygen Therapy The Third Affiliated Hospital of Inner Mongolia Medical UniversityBaotouInner MongoliaChina

Full-thickness skin grafting is one of the most commonly used repair methods for skin defects. It has the advantage of wear-resistant with less scar hyperplasia and less difficult to operate with no symptoms. Hyperbaric oxygen was used in this study after full-thickness skin grafting from September 2012 to August 2016 to achieve the best effect of skin survival after surgery.

关键词： Hyperbaric oxygen therapy Skin defects Full-thickness skin grafting

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“情感转向”与艺术情感理论话语范式的新变

西南大学学报（社会科学版） 2019年第5期45卷 141-148,200页

作者：周彦华四川美术学院当代视觉艺术研究中心

“情感转向”是近年来在哲学、社会学和人类学等领域广泛谈论的话题,传统的艺术理论同样在“情感转向”下发生变化。首先,艺术理论的“情感转向”挑战了艺术的“意义表征”体系,使经典艺术理论发生了转向;其次,因为“情感转向”关注身体... 详细信息

“情感转向”是近年来在哲学、社会学和人类学等领域广泛谈论的话题,传统的艺术理论同样在“情感转向”下发生变化。首先,艺术理论的“情感转向”挑战了艺术的“意义表征”体系,使经典艺术理论发生了转向;其次,因为“情感转向”关注身体,所以它在以“意义表征”为核心的经典艺术理论话语范式转向的基础上,又形成了以“身体感知”为核心的艺术情感理论话语范式的新变。再次,“情感转向”所形成的艺术情感理论从“元政治”角度重新定义“感性”的政治内涵,揭示了当代艺术与社会或美学与政治的新关系,构建了批判理论时代之后的“艺术-社会”观,为“后批判”时代的艺术批评提供了有别于批判理论的另类视角。

关键词：情感转向意义表征身体感知元政治后批判德勒兹格罗兹

“艺术介入”的去欧洲中心化转向与国际主义实验中的艺术介入社会

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西南大学学报（社会科学版） 2023年第2期49卷 242-252页

作者：周彦华四川美术学院视觉艺术研究院重庆401331

“去欧洲中心化转向”是目前国际学界研究艺术介入的热点视角。它重新审视了20世纪艺术介入与国际无产阶级运动的关系。国际无产阶级运动形成的“国际主义”思潮,深刻地影响了当时的艺术介入实践和理论。它一方面以大众化的、低技术性... 详细信息

“去欧洲中心化转向”是目前国际学界研究艺术介入的热点视角。它重新审视了20世纪艺术介入与国际无产阶级运动的关系。国际无产阶级运动形成的“国际主义”思潮,深刻地影响了当时的艺术介入实践和理论。它一方面以大众化的、低技术性的视觉形式鼓励无产阶级的参与,塑造无产阶级的主体性,从而反抗布尔乔亚趣味;另一方面,又以一种现实主义的手法,联合非西方世界的国家,批判殖民主义和帝国主义,建造新世界。艺术介入的国际主义体现在它“低可视性”和“直接现实主义”的国际主义视觉形式和杂糅先锋派美学反帝国主义与殖民文化的国际主义美学。这种国际主义美学同时也是一种让可感性进行分配的政治实践。中国的艺术介入属于20世纪初的国际主义艺术实验的一部分,它在将此种实验体制化的过程中逐渐成熟,形成了一种地方性的中国特色的艺术介入范式。它区别于今天西方民主政治主导的艺术介入,成为当代艺术介入的去欧洲中心化转向的典范。

关键词：艺术介入国际主义低可视性直接现实主义美学可感性分配