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2016～2018年中国生物力学研究进展

医用生物力学 2018年第6期33卷 477-482页

作者：陈维毅太原理工大学生物医学工程学院

生物力学已成为生物医学工程研究最活跃的领域之一。近年来,我国生物力学在细胞分子层次机制研究、基于生物力学理论和方法发展有疗效或有诊断意义的新概念和新技术方面取得了显著进展,有效地促进了生物医学基础与临床和人类健康与疾病... 详细信息

生物力学已成为生物医学工程研究最活跃的领域之一。近年来,我国生物力学在细胞分子层次机制研究、基于生物力学理论和方法发展有疗效或有诊断意义的新概念和新技术方面取得了显著进展,有效地促进了生物医学基础与临床和人类健康与疾病相关领域的研究。着重介绍近3年(2016～2018年)我国在心血管生物力学、骨肌系统生物力学、器官生物力学、细胞分子生物力学与力学生物学等方面所取得的进展情况。

关键词：生物力学力学生物学生物医学工程

基于正交试验设计的大掺量粉煤灰混凝土配合比

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混凝土 2022年第8期 1-5页

作者：陈炜一樊星李嵩阎培渝清华大学土木工程系北京100084 中建一局集团建设发展有限公司北京100013

使用正交试验法,进行用于超高层建筑的大体积底板的大掺量粉煤灰混凝土配合比设计。通过对正交试验结果的直观分析、极差分析、方差分析,得到了配合比中各主要变量对混凝土力学性能的影响规律。试验表明,大掺量粉煤灰混凝土的抗压强度... 详细信息

使用正交试验法,进行用于超高层建筑的大体积底板的大掺量粉煤灰混凝土配合比设计。通过对正交试验结果的直观分析、极差分析、方差分析,得到了配合比中各主要变量对混凝土力学性能的影响规律。试验表明,大掺量粉煤灰混凝土的抗压强度的影响因素依照显著性排序依次为粉煤灰掺量、水胶比和单位立方米胶材用量。大掺量粉煤灰混凝土的抗压强度随粉煤灰掺量和水胶比的升高而降低,胶凝材料用量在合理范围内变动的影响较小。基于各因素的显著性分析结果,给出了混凝土强度和放热性能满足要求的C40混凝土配合比,实际浇筑效果良好。

关键词：正交试验法配合比设计大掺量粉煤灰混凝土强度

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基于自适应正则化的超分辨率重建方法

强激光与粒子束 2014年第10期26卷 82-88页

作者：谢琦陈维义海军工程大学兵器工程系武汉430033

传统正则化超分辨重建得到的图像往往存在过度平滑或伪信息残留的问题,结合超分辨重建模型对重建图像伪信息的产生进行了分析,针对传统方法的不足提出了基于图像区域信息自适应的正则化方法,通过图像的区域信息将图像划分为平滑区与非... 详细信息

传统正则化超分辨重建得到的图像往往存在过度平滑或伪信息残留的问题,结合超分辨重建模型对重建图像伪信息的产生进行了分析,针对传统方法的不足提出了基于图像区域信息自适应的正则化方法,通过图像的区域信息将图像划分为平滑区与非平滑区域,对不同区域选用不同的先验模型进行约束。同时考虑人眼的视觉感知特性,结合区域信息实现正则化参数的自适应选取。实验结果表明该方法在抑制重建图像伪信息的同时能有效保护细节,效果要优于传统方法与单一的先验模型约束,对于红外与可见光图像重建效果的提升提供了一定的理论参考。

关键词：超分辨率图像序列分辨率增强自适应正则化图像重建

纳米银-二氧化钛填充树脂力学及光控抗菌性能研究

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生物医学工程学杂志 2022年第4期39卷 749-758页

作者：潘世奇鲁舒心李若玉张翔宇陈维毅太原理工大学材料科学与工程学院医用金属山西省重点实验室太原030024 太原理工大学生物医学工程学院太原030024

力学性能差和易引起细菌感染是牙科修复树脂在临床使用中所面临的主要问题。基于此,本研究通过合成具有良好光催化性能的银—二氧化钛(Ag-TiO_(2))纳米颗粒,并将其添加到复合树脂中,以期改善树脂的力学性能及光催化抗菌能力。首先,本文... 详细信息

力学性能差和易引起细菌感染是牙科修复树脂在临床使用中所面临的主要问题。基于此,本研究通过合成具有良好光催化性能的银—二氧化钛(Ag-TiO_(2))纳米颗粒,并将其添加到复合树脂中,以期改善树脂的力学性能及光催化抗菌能力。首先,本文对Ag-TiO_(2)纳米颗粒及复合树脂的微观结构和化学成分进行表征。结果表明,Ag以单质和氧化态两种形式存在于Ag-TiO_(2)中,而Ag-TiO_(2)纳米颗粒又均匀分散在复合树脂中。本文进一步的力学实验结果显示,Ag-TiO_(2)的填充显著提高了复合树脂的力学性能。而抗菌实验结果表明,在660 nm可见光照射下,由于光催化作用,Ag-TiO_(2)纳米颗粒填充复合树脂10 min即可显示出优良的抗菌能力;而在无光照条件下,随着Ag离子的释放,Ag-TiO_(2)纳米颗粒填充复合树脂24 h后也可展现优良抗菌性能。综上所述,本研究为牙科复合树脂领域提供了抗菌新思路。

关键词：复合树脂力学性能光控抗菌生物相容性

Meridional deflection of global eddy propagation derived from tandem altimetry: Mechanism and implication

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Science China Earth Sciences 2024年第3期67卷 811-825页

作者： Ge chen Xiaoyan chen Frontiers Science Center for Deep Ocean Multispheres and Earth System School of Marine TechnologyOcean University of ChinaQindao 266100China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQindao 266237China

A common view on meridional deflection of eddy propagation is poleward for cyclones and equatorward for anticyclones. This widely accepted polarity-sensitive pattern has been increasingly undermined given that it is systematically violated on both zonal and regional scales as recently reported. Here, we approach the problem by exploring these violations in terms of eddy effects of spatiotemporal geostrophy, thermal fading, and flow dragging, yielding the following main conclusions.(1) The polarity-dependent deflection discrepancy is a pseudo feature resulting from a biased fit to the normalized eddy tracks which are spatially asymmetric(though azimuthally symmetric) between the two signs;Instead, the primary pattern of eddy deflection appears to be geographically correlated and polarity independent.(2) Geostrophic adjustment plays a critical role in defining the meridional movement of an eddy. Specifically, a consistent poleward(equatorward) trajectory bending of spatially(temporally) ageostrophic eddies is observed irrespective of their polarity.(3) The mechanism of eddy deflection is also determined by its zonal propagation direction. Westward propagating eddies are substantially affected by thermal fading, while opposite ones by flow dragging. A realistic and comprehensive understanding of eddy deflection mechanisms serves as a significant contribution to the prediction of eddy trajectory, and the protection of ocean environment.

关键词： Mesoscale eddies Eddy propagation Eddy meridional deflection Satellite observation Geostrophic adjustment

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A refined representation method of the particle size distribution curve based on grading entropy

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Particuology 2024年第5期88卷 302-311页

作者： Xing Li Qun chen Zhaozhao Liu cheng Zhou chen Wang chen chen State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

The particle size distribution(PSD)curve is an important expression of the basic properties of the *** characteristic parameters such as median particle size D_(50),effective particle size D_(10),and some combinations of characteristic parameters can only represent some points of the PSD curve,failing to represent all information of the PSD *** this paper,a fraction characteristic parameter F that could reflect the fraction size variation of the PSD curve was introduced based on grading *** a new presentation method of the A-B-F three parameters was proposed for a refined representation of the PSD *** was found that the newly constructed model not only better represents the differences in the width of PSD curves but also has a higher sensitivity than the A-B two-parameter model proposed by Lő*** PSD curves with similar distributions,the new presentation method has a higher degree of discrimination than that of the D_(50)-C_(u)-C_(c) three-parameter or the four-parameter combination G_(c) proposed by ***,the application of this new method in describing the spatial nonuniformity distribution of depositions and predicting the soil hydraulic conductivity was *** research results can provide a reference for the refined representation of PSD curves.

关键词： Grading entropy Particle size distribution curve Refined representation

青藤碱通过调控PI3K/AKT通路介导的上皮间质转化抑制胰腺癌As PC-1细胞侵袭和转移

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中国现代应用药学 2022年第11期39卷 1419-1425页

作者：陈伟毅秦春宏陈延洪炼哲唐峰常德职业技术学院湖南常德415000 湖南医药学院湖南怀化418000 南华大学附属第二医院湖南衡阳421000

目的探讨青藤碱对胰腺癌AsPC-1细胞上皮间质转化(epithelial mesenchymal transition,EMT)、侵袭和转移的影响及机制。方法采用不同浓度青藤碱作用胰腺癌AsPC-1细胞后,划痕愈合试验检测细胞愈合能力,Transwell试验检测迁移细胞数和侵袭... 详细信息

目的探讨青藤碱对胰腺癌AsPC-1细胞上皮间质转化(epithelial mesenchymal transition,EMT)、侵袭和转移的影响及机制。方法采用不同浓度青藤碱作用胰腺癌AsPC-1细胞后,划痕愈合试验检测细胞愈合能力,Transwell试验检测迁移细胞数和侵袭细胞数,Westernblotting检测E-cadherin、N-cadherin、Vimentin、PI3K、p-PI3K、AKT、p-AKT蛋白表达。结果青藤碱降低AsPC-1细胞相对迁移率、迁移细胞数、侵袭细胞数。青藤碱上调E-cadherin蛋白表达、下调N-cadherin、Vimentin蛋白表达。青藤碱降低p-PI3K/PI3K、p-AKT/AKT比值。胰岛素生长因子-1逆转青藤碱对E-cadherin蛋白表达的上调和对N-cadherin、Vimentin蛋白表达的下调作用。TGF-β逆转青藤碱对AsPC-1细胞相对迁移率、迁移细胞数、侵袭细胞数的降低作用。结论青藤碱通过调控PI3K/AKT通路介导的EMT,抑制AsPC-1细胞侵袭和转移。

关键词：青藤碱胰腺癌侵袭转移上皮间质转化 PI3K/AKT通路

Track correlation algorithm based on CNN-LSTM for swarm targets

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Journal of Systems Engineering and Electronics 2024年第2期35卷 417-429页

作者： chen Jinyang WANG Xuhua chen Xian Research Institute for National Defense Engineering Academy of Military SciencesLuoyang 471023China Information Engineering University Zhengzhou 450001China School of Computer Science and Technology Xidian UniversityXi’an 710071China

The rapid development of unmanned aerial vehicle(UAV) swarm, a new type of aerial threat target, has brought great pressure to the air defense early warning system. At present, most of the track correlation algorithms only use part of the target location, speed, and other information for *** this paper, the artificial neural network method is used to establish the corresponding intelligent track correlation model and method according to the characteristics of swarm ***, a route correlation method based on convolutional neural networks (CNN) and long short-term memory (LSTM)Neural network is designed. In this model, the CNN is used to extract the formation characteristics of UAV swarm and the spatial position characteristics of single UAV track in the formation,while the LSTM is used to extract the time characteristics of UAV swarm. Experimental results show that compared with the traditional algorithms, the algorithm based on CNN-LSTM neural network can make full use of multiple feature information of the target, and has better robustness and accuracy for swarm targets.

关键词： track correlation correlation accuracy rate swarm target convolutional neural network(CNN) long short-term memory(LSTM)neural network

Aerial target threat assessment based on gated recurrent unit and self-attention mechanism

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Journal of Systems Engineering and Electronics 2024年第2期35卷 361-373页

作者： chen chen QUAN Wei SHAO Zhuang School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China

Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced ***, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

关键词： target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)