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A Joint Delay-and-Sum and Fourier Beamforming Method for High Frame Rate Ultrasound Imaging

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Computer Modeling in Engineering & Sciences 2020年第4期123卷 427-440页

作者： Wei Zhao Shuai Feng yadan wang Yuanguo wang Zhihui Han Hu Peng Department of Biomedical Engineering Hefei University of TechnologyHefei230009China Yijishan Hospital of Wannan Medical College Wuhu241001China

Frame rate is an important metric for ultrasound imaging systems,and high frame rates(HFR)benefit moving-target *** common way to obtain HFR imaging is to transmit a plane ***-and-sum(DAS)beamformer is a conventional beamforming algorithm,which is simple and has been widely implemented in clinical *** beamforming is an alternative method for HFR imaging and has high levels of imaging efficiency,imaging speed,and good temporal dynamic ***,the resolution and contrast performance of HFR imaging based on DAS or Fourier beamforming are insufficient due to the single plane wave *** address this problem,a joint DAS and Fourier beamforming method is introduced in this *** proposed method considers the different distributions of sidelobes in DAS imaging and Fourier imaging and combines the angular spectrum and DAS to reconstruct ultrasound *** proposed method is evaluated on simulation and experimental phantom datasets to compare its performance with DAS and Fourier beamforming *** demonstrate that the proposed method improves image effective dynamic range and resolution while also retaining a high frame rate of the ultrasound imaging *** proposed method improves the effective dynamic range along axial and lateral directions by 10 dB,compared to standard DAS and Fourier beamforming.

关键词： High frame rate imaging delay-and-sum Fourier transformation angular spectrum.

Mixed-Alkali Effect on Thermal Property and Elastic Behavior in Borosilicate Glasses

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 1017-1024页

作者： XIE Xianmao ZHOU Hemin KE Xuefei wang Xiaowei wang yadan ZHANG Jiayan QIAO Ang TAO Haizheng State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China AVIC Jonhon Optronic Technology Co.Ltd. Luoyang 471003China Wuhan University of Technology Advanced Engineering Technology Research Institute of Zhongshan City Zhongshan 528437China

We investigated the mixed alkali effect on the thermal properties and elastic response to temperature in the borosilicate glasses system with the composition of 70.65Si O_(2)·21.09B_(2)O_(3)·1.88Al_(2)O_(3)·(6.38-x)Li_(2)O·x Na_(2)O glasses,where x=0.00,1.595,3.19,4.785,and *** for the expected positive and negative deviations from linearity for the coefficients of thermal expansion,room temperature E and G,we observed a new mixed alkali efiect on the response of elastic moduli to *** transform infrared spectra were obtained to elucidate the possible structural origin of the mixed alkali *** work provides a valuable insight into the structural and mechanical properties of mixed-alkali borosilicate glasses.

关键词： mixed-alkali effect borosilicate glass elastic response to temperature structural origin

A Modified Full-NT-Step Infeasible Interior-Point Algorithm for SDP Based on a Specific Kernel Function

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Journal of Harbin Institute of Technology(New Series) 2019年第2期26卷 41-47页

作者： yadan wang Hongwei Liu Zexian Liu Department of Mathematics Xidian University School of Mathematics and Computer Science Hezhou University

This paper proposes a new full Nesterov-Todd(NT) step infeasible interior-point algorithm for semidefinite programming. Our algorithm uses a specific kernel function, which is adopted by Liu and Sun, to deduce the feasibility step. By using the step, it is remarkable that in each iteration of the algorithm it needs only one full-NT step, and can obtain an iterate approximate to the central path. Moreover, it is proved that the iterative bound corresponds with the known optimal one for semidefinite optimization problems.

关键词： semidefinite programming infeasible interior-point methods full Nesterov-Todd steps kernel functions polynomial complexity

Lubrication Mechanism of Nanoparticles in Metal Hot Deformation

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Lubrication Mechanism of Nanoparticles in Metal Hot Deformat...

A prelimary study of immunogenicity analysis of the PPE proteinfamily from mycobacterium tuberculosis

2014中国功能材料科技与产业高层论坛

作者： Niu Tailong Sun Jianlin wang yadan Zhu Zuoxin Li Yan Schoolof Materials Science and Engineering University of Science and Technology Beijing

ISBN: (纸本)9783038353522

Effect of nanoparticlesto improve the lubrication load capacity and resistance to extreme pressure of water-based rolling liquidwas studied by fourball *** experimentswere conductedin different lubrication conditionswith nanoparticlesusing Gleeble hot compression simulation *** the residual nanoparticles characteristics and the surface morphology of the compressed sample were analyzed by SEM and *** results show that water-basednano-TiO lubricant can efficiently reduce the friction during metal ***-ZnO is preferred to adhere to metal surfaces andemployed to isolate the surfaces.A new lubricating mechanism of nanoparticles in metal hot deformation named convex peak extreme pressure buffering mechanismis thereby proposed,whichis verifiedby the surface morphology of compressed sample.

关键词： Nano Lubricant Mechanism

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A prelimary study of immunogenicity analysis of the PPE prot...

生命的分子机器及其调控网络——2012年全国生物化学与...

作者： yadan wang Hui MA Xiaoyong FAN Fudan TONG Institute of Biochemistry College of Life ScienceZhejiang Scitech University Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine

TB(Tuberculosis) is chronic disease caused by Mycobacterium tuberculosis which also makes animal disease,which is still the main threat to human health diseases *** traditional method of diagnosis Tuberculosis is susceptible to many factors interfere and produce a higher false positive diagnosis results or false negative diagnosis results,is not conducive to the early diagnosis and treatment of *** is a need to develop newer and more efcient diagnostic tests that can identify most of the TB

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我如何治疗弥散性血管内凝血

中华血液学杂志 2017年第5期38卷 371-374页

作者：胡豫王雅丹华中科技大学同济医学院附属协和医院武汉430022

弥散性血管内凝血（DIC）是在某些严重疾病基础上，由特定诱因引发的复杂的病理过程，包括由致病因素引起人体凝血系统激活、血小板活化、纤维蛋白沉积，导致弥散性血管内微血栓形成；继之消耗性降低多种凝血因子和血小板；在凝血系统... 详细信息

弥散性血管内凝血（DIC）是在某些严重疾病基础上，由特定诱因引发的复杂的病理过程，包括由致病因素引起人体凝血系统激活、血小板活化、纤维蛋白沉积，导致弥散性血管内微血栓形成；继之消耗性降低多种凝血因子和血小板；在凝血系统激活的同时，纤溶系统亦可激活，导致纤溶亢进。

关键词：弥散性血管内凝血凝血系统激活血小板活化治疗纤维蛋白沉积微血栓形成病理过程致病因素

强制性公民行为对知识型员工离职倾向的影响研究:一个有调节的中介模型

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科技管理研究 2018年第5期38卷 159-165页

作者：周霞王亚丹华南理工大学广东广州510641

通过对广深两地科技企业的242名知识型员工进行实证研究,探讨强制性公民行为对知识型员工离职倾向的影响,以及情绪衰竭的中介作用和心理资本的调节作用。研究结果显示,强制性公民行为对知识型员工离职倾向有显著的正向影响,情绪衰竭在... 详细信息

通过对广深两地科技企业的242名知识型员工进行实证研究,探讨强制性公民行为对知识型员工离职倾向的影响,以及情绪衰竭的中介作用和心理资本的调节作用。研究结果显示,强制性公民行为对知识型员工离职倾向有显著的正向影响,情绪衰竭在两者的关系中起部分中介作用;心理资本负向调节强制性公民行为与情绪衰竭的关系,同时也调节了强制性公民行为通过情绪衰竭对离职倾向的间接作用。

关键词：知识型员工强制性公民行为离职倾向情绪衰竭心理资本

中国科技服务业政策的量化与演变——基于扎根理论和文本挖掘分析

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中国科技论坛 2018年第6期 6-13页

作者：张骁周霞王亚丹华南理工大学工商管理学院广东广州510641

为促进科技服务业的发展,收集了2006—2016年中国科技服务业政策,预处理后得到227条政策文本。基于扎根理论提取75个关键词进行文本挖掘分析,结合政策工具视角发现:中国科技服务业政策侧重于技术转移、知识产权服务等领域,缺乏对研究开... 详细信息

为促进科技服务业的发展,收集了2006—2016年中国科技服务业政策,预处理后得到227条政策文本。基于扎根理论提取75个关键词进行文本挖掘分析,结合政策工具视角发现:中国科技服务业政策侧重于技术转移、知识产权服务等领域,缺乏对研究开发服务、检验检测和科技金融等的关注;多政策主体的协同政策缺乏,激励性政策措施运用不足,政策措施组合单调;政策工具应用不均衡,有过溢风险和挤出效应。据此提出对策建议。

关键词：科技服务业科技政策扎根理论文本挖掘

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文丘里管扩张段湿气流动特性与结构优化

机械科学与技术 2018年第8期37卷 1272-1279页

作者：徐英王雅丹张涛汪晶晗天津大学电气自动化与信息工程学院天津300072

对文丘里管扩张段加速压降和摩阻压降进行理论分析,利用计算流体力学(Computational fluid dynamics,CFD)数值模拟方法针,对管径50 mm,节流比0.55的长喉颈文丘里,从扩张角度和扩张段形状入手设计了4种结构,寻找适合湿气流动且能提高文... 详细信息

对文丘里管扩张段加速压降和摩阻压降进行理论分析,利用计算流体力学(Computational fluid dynamics,CFD)数值模拟方法针,对管径50 mm,节流比0.55的长喉颈文丘里,从扩张角度和扩张段形状入手设计了4种结构,寻找适合湿气流动且能提高文丘里前后差压比值K对液相体积含率LVF线性辨识能力的最优结构。模拟结果与理论分析吻合,表明差压比值K随扩张角度增加而增大,但难以实现线性辨识。扩张段采用椭圆弧结构,可通过减小加速压降增大摩阻压降提高K值对液相的分辨能力。同时必须保证扩张段与后直管段平缓连接,从而确保湿气流动形态稳定。椭圆弧结构与直线结构平缓相接的扩张段模型在保证湿气流动稳定前提下,将差压比K与LVF的线性度由原先的1.5%拓宽到4.5%。

关键词：文丘里扩张段湿气加速压降摩阻压降差压比值液相体积含率