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基于基本解的杂交有限元法计算应力强度因子

郑州大学学报（工学版） 2011年第4期32卷 26-29,51页

作者：郑冠雨王辉重庆大学土木工程学院重庆400030 河南工业大学土木建筑学院河南郑州450052

含有裂纹的工程结构的应力奇异性表征通常需要借助应力强度因子.结合位移外推法,采用基于单元边界积分的杂交有限元法给出了平面I型(张开型)裂纹的应力强度因子的计算方法.解析满足控制方程基本解的线性组合被用来近似表达单元内部的位... 详细信息

含有裂纹的工程结构的应力奇异性表征通常需要借助应力强度因子.结合位移外推法,采用基于单元边界积分的杂交有限元法给出了平面I型(张开型)裂纹的应力强度因子的计算方法.解析满足控制方程基本解的线性组合被用来近似表达单元内部的位移场和应力场,而普通的形函数插值则被用于近似表达单元边界位移场.二者通过杂交泛函联系起来,并且泛函中所有单元域积分被完全转化为单元边界积分.两个典型断裂问题的计算结果显示该方法具有精度高的优点,可以方便地用于断裂问题的应力强度因子计算.

关键词：断裂力学应力强度因子基本解杂交有限元法

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基于Stiefel流形的粒子滤波器研究

物理学报 2010年第12期59卷 8316-8321页

作者：朱志宇杨官校江苏科技大学电子信息学院镇江212003

为了解决粒子滤波的粒子退化和粒子多样性丧失问题,提出了一种基于Stiefel流形的粒子滤波算法.该算法将系统模型置于Stiefel流形上,用朗之万分布描述过程转移概率分布,用矩阵正态分布表示似然函数分布,在流形分布上进行粒子采样.在计算... 详细信息

为了解决粒子滤波的粒子退化和粒子多样性丧失问题,提出了一种基于Stiefel流形的粒子滤波算法.该算法将系统模型置于Stiefel流形上,用朗之万分布描述过程转移概率分布,用矩阵正态分布表示似然函数分布,在流形分布上进行粒子采样.在计算加权粒子的均值时,将流形嵌入到欧氏空间中,先计算欧氏空间中的粒子均值,再将计算结果投影到嵌套流形上,这就排除了噪声统计特性对粒子权重方差的影响,得到了一种受系统状态模型限制较少的重要性概率密度函数通用选择方案.仿真时选取单变量非静态增长模型,仿真结果验证了该算法的实时性、鲁棒性,滤波精度和滤波效率均比无味粒子滤波算法更好.

关键词：粒子滤波 Stiefel流形单变量非静态增长模型

Iontronic pressure sensor with high sensitivity and linear response over a wide pressure range based on soft micropillared electrodes

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Science Bulletin 2021年第11期66卷 1091-1100,M0003页

作者： Peng Lu Liu wang Pang Zhu Jun Huang yueji wang Ningning Bai Yan wang Gang Li Junlong Yang Kewei Xie Jianming Zhang Bo yu yuan dai Chuan Fei Guo department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Ningbo Fengcheng Advanced Energy Materials Research Institute Ningbo 315500China Tencent Robotics X Shenzhen 518000China Centers for Mechanical Engineering Research and Education at MIT and SUSTech&Shenzhen Engineering Research Center for Novel Electronic Information Materials and devices Southern University of Science and TechnologyShenzhen 518055China

Electronic skins and flexible pressure sensors are important devices for advanced healthcare and intelligent *** is a key parameter of flexible pressure *** introducing surface microstructures in a capacitive-type sensor can significantly improve its sensitivity,the signal becomes nonlinear and the pressure response range gets much narrower,significantly limiting the applications of flexible pressure ***,we designed a pressure sensor that utilizes a nanoscale iontronic interface of an ionic gel layer and a micropillared electrode,for highly linear capacitance-to-pressure response and high sensitivity over a wide pressure *** micropillars undergo three stages of deformation upon loading:initial contact(0-6 k Pa)and structure buckling(6-12 k Pa)that exhibit a low and nonlinear response,as well as a post-buckling stage that has a high signal linearity with high sensitivity(33.16 k Pa-1)over a broad pressure range of 12-176 k *** high linearity lies in the subtle balance between the structure compression and mechanical matching of the two materials at the gel-electrode *** sensor has been applied in pulse detection,plantar pressure mapping,and grasp task of an artificial *** work provides a physical insight in achieving linear response through the design of appropriate microstructures and selection of materials with suitable modulus in flexible pressure sensors,which are potentially useful in intelligent robots and health monitoring.

关键词： Iontronic interface Linearity Flexible pressure sensor Mechanical matching

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ADS无窗靶件自由界面模拟实验和数值研究

原子能科学技术 2012年第2期46卷 186-191页

作者：苏冠宇顾汉洋程旭上海交通大学核科学与工程学院上海200240

冷却剂自由界面形态的形成和控制是加速器驱动的次临界系统(ADS)无窗靶件设计的关键技术之一。采用水介质对无窗靶件模型的自由界面特征进行了实验和数值研究。实验中采用激光诱导荧光的示踪方法实现了流场的可视化,得到Re=30 000～50 ... 详细信息

冷却剂自由界面形态的形成和控制是加速器驱动的次临界系统(ADS)无窗靶件设计的关键技术之一。采用水介质对无窗靶件模型的自由界面特征进行了实验和数值研究。实验中采用激光诱导荧光的示踪方法实现了流场的可视化,得到Re=30 000～50 000范围内的自由界面和可视化流场。在高Re工况下,流场中出现大尺度的非稳定涡结构,随着Re的降低,流场中涡结构的紊乱程度增加。分别采用大涡模型(LES)和两方程动能-特征耗散率模型(kω-SST)对无窗靶件实验工况进行了数值分析,计算结果表明,LES能较好地模拟实验中所得的流场现象和界面特征。

关键词：无窗靶件自由界面流场可视化大涡模型

基金竞赛还是职业生涯关注?——对基金经理风险选择的实证研究

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管理工程学报 2013年第2期27卷 65-70页

作者：饶育蕾王颖戴鹏君中南大学商学院湖南长沙410083 广发证券山西太原030071

本文选取我国2004年—2009年开放式股票型基金,从基金经理职业生涯关注的角度,研究前期基金业绩相对排名对后期基金经理投资组合风险选择的影响,得出与基金竞赛理论不同的结论:前期业绩排名居前与靠后的基金,后期都会选择高风险。由于... 详细信息

本文选取我国2004年—2009年开放式股票型基金,从基金经理职业生涯关注的角度,研究前期基金业绩相对排名对后期基金经理投资组合风险选择的影响,得出与基金竞赛理论不同的结论:前期业绩排名居前与靠后的基金,后期都会选择高风险。由于基金业绩相对排名与基金经理的从业经历决定了基金经理的职业生涯状况,由此引发职业生涯关注,导致前期业绩相对排名与风险选择之间存在正U型关系,并且基金经理从业经历越欠缺,U型关系越明显。

关键词：职业生涯关注风险选择基金业绩

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超临界水中木质素/CMC催化气化制氢

太阳能学报 2007年第10期28卷 1140-1145页

作者：关宇郭烈锦裴爱霞西安交通大学动力工程多相流国家重点实验室西安710049

在间歇式高压反应釜中,以碱性化合物K_2CO_3和Ca(OH)_2以及Ru/C为催化剂,对木质素在超临界水中的气化制氢特性进行了实验研究。结果表明:3种催化剂都有较好的催化作用,其中Ru/C的效果最佳,几种催化剂混合使用的效果要比单独一种催化剂... 详细信息

在间歇式高压反应釜中,以碱性化合物K_2CO_3和Ca(OH)_2以及Ru/C为催化剂,对木质素在超临界水中的气化制氢特性进行了实验研究。结果表明:3种催化剂都有较好的催化作用,其中Ru/C的效果最佳,几种催化剂混合使用的效果要比单独一种催化剂使用时好,但是其提高的幅度不很明显。另外,随着温度的升高,H_2和CH_4的产气量以及氢转化率等都相应的升高。

关键词：生物质超临界水气化制氢

MICROHARDNESS DISTRIBUTION AT INTERFACE OF(N^++IP)-TiN COMPOSITE COATINGS ON STEEL

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Acta Metallurgica Sinica(English Letters) 1992年第8期5卷 110-113页

作者： JIN Zhujing yu Li yu Zhiming dai Shaoxia XU Jiayin Institute of Corrosion and Protection of Metals,Academia Sinica,Corrosion Science Laboratory Academia Sinica,Shenyang,China

The composite coating of(N^++IP)-TiN was prepared by ion-plated TiN film onto ion-nitrided case on the low carbon steel *** microhardness measurement along in- terface between IP-TiN coating and substrate was detected as a moderate decrease in magni- tude with increase of distance from the coating *** seems due to the occurrence of ion nitride case,ε-Fe_3N-Fe_2N and Fe_4N phases,along the interface.

关键词： microhardness composite coating interface ion-plating ion

Characteristics and management strategy of the devices configured in Baosteel's domestically-integrated 60000 m^3/h air separation unit

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Baosteel Technical Research 2009年第3期3卷 32-37页

作者： YANG Zhen HU Ke yu Liangzhu dai Zhong ZHANG Guoping Energy ＆ Environment department Baoshan Iron ＆ Steel Co. Ltd. Shanghai 200941 China

Baosteel＇ s No. 8 air separation unit（ASU） is the first domestically-integrated 60 000 m^3/h ASU. This paper describes the mechanical equipment, the design and the configuration characteristics of this unit. The potential failure modes of the mechanical devices are deduced via analyses on the failure history of similar devices in other ASUs. Finally, this paper also brings up suggestions on daily maintenance, overhaul and purchases of spare parts.

关键词： air separation unit localization equipment management maintenance spare parts

Effects of pricking blood therapy at meridian sinews on upper limb spasm of post-stroke patients

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World Journal of Acupuncture-Moxibustion 2020年第1期30卷 39-44页

作者： Ling-shu wang guan-nan LI Xue-tong GU yuan-yuan BI Chun-yu ZHANG The First Affiliated Hospital of Heilongjiang University of Tradirional Chinese Medicine Harbin 150060China Heilongjiang University of Traditional Chinese Medicine Harbin 150040China

Objective:To observe effects of pricking blood therapy at meridian sinews on upper limb spasm of poststroke ***:A total of 72 patients with post-stroke upper limb spasm were randomly divided into a comprehensive group of pricking blood therapy at meridian sinews with rehabilitation training(comprehensive group)and the simple rehabilitation training group(rehabilitation group),and there were 36 patients in each *** the basis of routine therapy,the patients of the two groups received rehabilitation therapy for 6 consecutive days and 1-day rest,for 4 weeks in *** the above basis,the patients in the comprehensive group received pricking blood therapy at meridian sinews,once every other day,3 times per week,for 4 weeks in *** treatment,after the first treatment,and after 4-week treatment,the patients were observed for changes of upper limb spasticity(Modified Ashworth Scale,MAS),upper limb movement function(Fugl-Meyer Assessment,FMA),activity of daily living(Modified Barthel Index,MBI),and biceps and triceps integrated electromyogram(IEMG)values were observed as well as the therapeutic ***:(1)After the first treatment,there were statistically significant differences of the MAS scale grades in patients of the two groups(P0.05).(2)After 4-week treatment,there were statistically significant differences of MAS grades in patients of the two groups(P<0.05).The FMA and MBI scores in the two groups were increased than those before treatment(all P<0.05),and the FMA and MBI scores in the comprehensive group were higher than those in the rehabilitation

关键词： Stroke Upper limb spasm Meridian sinews Pricking blood therapy Integrated electromyogram(IEMG)