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Journal of Hydrodynamics 2002年第4期14卷 73-80页

作者： Ren, An-Lu Zou, Jian-Feng zhou, yong-xia Li, Guang-Wang Dept. of Mech. Zhejiang Univ. Hangzhou 310027 China

It was proved numerically that the Domain Decomposition Method CDDM) with one layer overlapping grids is identical to the block iterative method of linear algebra equations. The results obtained by using DDM could be in reasonable agreement with the results of full-domain simulation. With the three dimensional solver developed by the authors, the flow field in a pipe was simulated by using the full-domain DDM with one layer overlapping grids and with patched grids respectively. Both of the two cases led to the convergent solution. Further research shows the superiority of the DDM with one layer overlapping grids to the DDM with patched grids. A comparison between the numerical results obtained by the authors and the experimental results given by Enayet[3] shows that the numerical results are reasonable.

关键词： Computational fluid dynamics Computer simulation Iterative methods Linear equations Viscous flow

NUMERICAL SOLUTION OF 2-D INCOMPRESSIBLE VISCOUS FLOW WITH HIGH ORDER COMPACT SCHEME USING DOMAIN DECOMPOSITION AND MATCHED METHOD

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Journal of Hydrodynamics 2001年第4期13卷 79-82页

作者： Ren, An-Lu Lu, xiao-Dong Zou, Jian-Feng zhou, yong-xia Dept. of Mech. Zhejiang Univ. Hangzhou 310027 China

This paper presents a high-accuracy method for solving 2-D incompressible viscous N-S equations in tensor forms. A domain decomposition method was used to divide the computational domain into several regular blocks with the overlapping grid in order to transfer data between sub-domains and to remove numerical singularity caused by domain decomposition. Using the method and algorithm presented above, the flow passing an ellipse was computed and the formation and evolution of the vortex shedding was successfully simulated.

关键词： Computational fluid dynamics Computational methods Incompressible flow Navier Stokes equations

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基于物理的实时人体动画

浙江大学学报（工学版） 2006年第12期40卷 2079-2082页

作者：郁佳荣石教英周永霞浙江大学CAD&CG国家重点实验室浙江杭州310027

为了快速而生动地实现人体动画,提出了一种骨架驱动的人体动画的新模型.该模型的结构分线骨骼、三维中间层和控制网格体三层.用截面变形法实现规则三维中间层在线骨骼驱动下的变形;在生物力学的基础上,使用扩展的自由变形技术对不规则... 详细信息

为了快速而生动地实现人体动画,提出了一种骨架驱动的人体动画的新模型.该模型的结构分线骨骼、三维中间层和控制网格体三层.用截面变形法实现规则三维中间层在线骨骼驱动下的变形;在生物力学的基础上,使用扩展的自由变形技术对不规则三维中间层进行变形.用线性有限元方法,得到了大型稀疏线性方程组,利用预处理共轭梯度法求解了方程组的解,实现了三维中间层对控制网格体的驱动.在控制网格体中嵌入人体皮肤,利用线性插值法,计算得到皮肤变形.实验结果表明,该模型能达得实时性,并能方便地实现肢体的弯曲和扭转.

关键词：基于物理的动画三层次结构有限元法实时变形扩展的自由变形

一种注意力机制与SRGAN网络结合的超分辨率算法

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小型微型计算机系统 2021年第12期42卷 2587-2591页

作者：章韬略周永霞中国计量大学信息工程学院杭州310018

超分辨率是指将一张低分辨率图片转换成高分辨率,在军事领域、工业领域等都有着重要作用.基于生成对抗网络(GAN)的超分变率方法,主要是根据生成对抗网络原理,由生成器生成一张伪高分辨率图片,再由鉴别器计算这张图片与真实高分辨率图片... 详细信息

超分辨率是指将一张低分辨率图片转换成高分辨率,在军事领域、工业领域等都有着重要作用.基于生成对抗网络(GAN)的超分变率方法,主要是根据生成对抗网络原理,由生成器生成一张伪高分辨率图片,再由鉴别器计算这张图片与真实高分辨率图片的差值,来衡量这张图片的真实程度.本文基于SRGAN(Super-resolution Generative Adversarial Network)网络主要进行了3点改进:(1)引入了注意力通道机制,即在SRGAN网络中加入CA(Channel Attention)模块,同时增加网络深度以更好的表达高频特征;(2)删除原有的BN(Batch Normalization)层以提升网络性能;(3)修改损失函数,以减少噪声对图片的影响.通过实验表明,本文所采用的方法改善了伪影问题,在Set5、Set10、BSD100测试集上均提升了PSNR(峰值信噪比).

关键词：超分辨率 GAN网络注意力机制损失函数

基于新Haar-like特征的多角度人脸检测

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计算机工程 2009年第19期35卷 195-197页

作者：刘晓克孙燮华周永霞中国计量学院信息工程学院杭州310018

在Haar-like特征的基础上增加新的检测特征,给出特征计算方法和积分方法,实现多角度人脸检测。将多角度人脸分为3类,即全侧脸、半侧脸和正面人脸。利用连续Adaboost算法训练各类人脸检测器,用金字塔式结构将各类人脸检测器级联成一个多... 详细信息

在Haar-like特征的基础上增加新的检测特征,给出特征计算方法和积分方法,实现多角度人脸检测。将多角度人脸分为3类,即全侧脸、半侧脸和正面人脸。利用连续Adaboost算法训练各类人脸检测器,用金字塔式结构将各类人脸检测器级联成一个多角度人脸检测器。在CMU人脸检测集合上,该检测器的成功率为85.2%,高于Adaboost算法和浮点Adaboost算法。

关键词： Haar—like特征特征计算连续Adaboost算法金字塔式结构

一种结合Alphapose和LSTM的人体摔倒检测模型

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小型微型计算机系统 2019年第9期40卷 1886-1890页

作者：卫少洁周永霞中国计量大学信息工程学院

针对已有人体摔倒检测模型在不同检测场景下适应性差、误检率高等缺点,本文提出了一种基于人体骨骼关键点和LSTM神经网络的人体摔倒检测模型.该模型通过Alphapose对连续多帧中的人体进行骨骼关键点检测,然后将骨骼关键点坐标序列分为x... 详细信息

针对已有人体摔倒检测模型在不同检测场景下适应性差、误检率高等缺点,本文提出了一种基于人体骨骼关键点和LSTM神经网络的人体摔倒检测模型.该模型通过Alphapose对连续多帧中的人体进行骨骼关键点检测,然后将骨骼关键点坐标序列分为x坐标序列和y坐标序列,分别输入两个LSTM神经网络进行时序特征提取,最后将LSTM隐层输出向量输入一个全连接层得到检测结果.本文使用公开数据集MuHAVi-MAS和Le2i进行实验,并与多种检测模型进行对比,实验结果表明本文方法在多场景、多视角和多姿势摔倒情况下都具有较高的检测精度.

关键词：摔倒检测模型 Alphapose 骨骼关键点 LSTM

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin Yuan Weicheng Kong Pengcheng xia Yuanrong Li Yuewei Chen Nian Liu Jing He Jue Shi Zihe Hu Yanyan zhou Zhijian Xie yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

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城市煤气甲烷化工艺的化学能损失

天然气化工—C1化学与化工 1999年第5期24卷 16-20页

作者：夏素兰朱家骅周勇夏代宽四川大学化工学院成都610065

通过解析城市煤气甲烷化过程化学能的损失，指出ＣＯ变换应以满足甲烷化反应要求为限，过度变换会造成无谓的化学能损失且降低产品气热值。提出以国家标准规定的城市煤气热值下限和ＣＯ含量上限为控制指标的参数准则，并在２－５Ｌ ... 详细信息

通过解析城市煤气甲烷化过程化学能的损失，指出ＣＯ变换应以满足甲烷化反应要求为限，过度变换会造成无谓的化学能损失且降低产品气热值。提出以国家标准规定的城市煤气热值下限和ＣＯ含量上限为控制指标的参数准则，并在２－５Ｌ级现场实验中得到了验证。

关键词：煤气甲烷化变换化学能损失一氧化碳

Cloning, Expression of Human C Reactive Protein and Identification of its Immune Reactivity

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Cloning, Expression of Human C Reactive Protein and Identifi...

湖北省暨武汉生物化学与分子生物学学会第八届会员代表大会和第十五次学术年会

作者： ZHENG Fang, zhou Xin, xia yong, ZHAO Lie, Hu Han-ling, JIANG Xin-Qiang. Department of laboratory Medicine, Wuhan University School of Medicine, Wuhan 430071, China

AIM: To develop an expression, purification system of recombinant E. coli which can express C reactive protein (CRP) and to identify the immune reactivity of the CRP to anti-CRP specific antibody. METHOD: The CRP cDNA was amplified by RT-PCR from human liver eDNA library and inserted into expression vector pCRT7/NT. The recombined plasmid CRP-pCRT7/NT which expressed the fusion protein of CRP was then transferred into lysogenic host strain E coll. BL21(DE3). The target protein was identified using SDS-polyacrylamide gel electrophoresis(SDS-PAGE). Affinity chromatography was used for protein purification. The immune reactivity of purified CRP was identified by Western blot using anti-CRP specific antibody. RESULTS and CONCLUSION: A plasmid expressed CRP protein was constructed and the purification system of CRP protein was established. The immune reactivity of the purified protein was identified by Western blot, which made a good foundation for the preparation of CRP test kit.

关键词： C reactive protein cloning expression purification Western blot

来源： cnki会议评论

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肾上腺静脉MSCT影像解剖研究

中国临床解剖学杂志 2015年第3期33卷 278-283页

作者：李晓燕吕发金周永霞张翱胡良波刘丹重庆医科大学附属永川医院重庆永川402160 重庆医科大学附属第一医院重庆400016

目的利用MSCT准确显示肾上腺静脉正常解剖结构及变异,为临床提供影像解剖数据。方法回顾分析上腹部CTA患者108例。薄层MIP/MPR评估测量肾上腺静脉管径、长度及走行路径。结果 1右侧:显示率64.81%(70/108),变异5.71%(4/70);汇入下腔静脉... 详细信息

目的利用MSCT准确显示肾上腺静脉正常解剖结构及变异,为临床提供影像解剖数据。方法回顾分析上腹部CTA患者108例。薄层MIP/MPR评估测量肾上腺静脉管径、长度及走行路径。结果 1右侧:显示率64.81%(70/108),变异5.71%(4/70);汇入下腔静脉7点至8点间占优势42.42%;其管径Rr(2.19±0.56)mm,腺外段长度RD1(5.02±1.82)mm,汇入下腔静脉距右肾静脉汇入距离RD2(40.69±12.96)mm,汇入口开口向下角度RA(60.25±17.85)°。2左侧:显示率97.22%(105/108);变异14.29%(15/105);肾上腺静脉管径Lr(2.39±0.56)mm,腺外段长度LD1(7.28±4.01)mm,膈-肾上腺静脉干管径LR(3.65±0.93)mm,膈-肾上腺静脉的共干段长度LD2(14.07±6.77)mm,膈-肾上腺静脉汇入左肾静脉点至下腔静脉左侧缘距离LD3(32.89±4.85)mm,膈-肾上腺静脉汇入左肾静脉开口向内的角度LA1(118.06±18.49)°,肾上腺静脉与膈静脉共干段开口向下的角度LA2(156.15±13.81)°。结论 MSCT可显示大部分右侧肾上腺静脉及绝大部分左侧肾上腺静脉正常走行及变异,测量相关影像解剖数据,为AVS等手术方案提供影像数据。

关键词：肾上腺静脉计算机断层摄影影像解剖变异