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Attention-based novel neural network for mixed frequency data

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CAAI Transactions on Intelligence Technology 2021年第3期6卷 301-311页

作者： xiangpeng li Hong Yu Yongfang Xie Jie li Chongqing key Laboratory of Computational Intelligence Chongqing University of Posts and TelecommunicationsChongqingChina School of Information Science and Engineering Central South UniversityChangshaChina School of Metallurgy and Environment Central South UniversityChangshaChina

It is a common fact that data(features,characteristics or variables)are collected at different sampling frequencies in some fields such as economic and *** existing methods usually either ignore the difference from the different sampling frequencies or hardly take notice of the inherent temporal characteristics in mixed frequency *** authors propose an innovative dual attention-based neural network for mixed frequency data(MID-DualAtt),in order to utilize the inherent temporal characteristics and select the input characteristics reasonably without losing *** to the authors’knowledge,this is the first study to use the attention mechanism to process mixed fre-quency *** MID-DualAtt model uses the frequency alignment method to trans-form the high--frequency variables into observation vectors at low frequency,and more critical input characteristics are selected for the current prediction index by attention *** temporal characteristics are explored by the encoder-decoder with attention based on long-short-term memory networks(LSTM).The proposed MID-DualAtt has been tested in practical application,and the experimental results show that it has better prediction ability than the compared models.

关键词： network decoder mixed

Synthesis and characterization of ultra-soft alginate hydrogel mimicking lung tissue

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International Journal of Smart and Nano Materials 2024年第3期15卷 593-609页

作者： xiangpeng li Jihua Gou Chiranjit Maiti Olusegun J.Ilegbusi Department of Mechanical and Aerospace Engineering University of Central FloridaOrlandoFLUSA

Alginate hydrogels possess properties analogous to those of the extracellular matrix(ECM).Thus,their mechanical behavior approx-imates soft tissue,which makes them desirable for the production of tissue-equivalent soft deformable *** study aims to determine the synthesis-structure-property relationship for alginate hydrogel with the Young’s modulus in the range of 10°~101 kPa,mimicking to that of human lung ***,a 3D polymer network embedded in a water-rich *** alginate hydrogels are synthesized by a direct mixture of sodium alginate and CaCO3,followed by the addition of D-glucono-δ-lactone(GDL)to initiate in-situ Ca^(2+)release and *** influence of alginate concentration and molar ratio of the constitu-ent calcium ion to carboxyl group from alginate monomer are evaluated while the Young’s modulus of the hydrogel is carefully controlled within the desired *** and SEM are used to characterize the influence of synthesis parameters at the molecular and microstructure *** and compression testing are performed to determine the Young’s modulus of the *** relations are established between synthesis parameters and the mechanical *** result of the study will be subse-quently used to guide the additive manufacturing of soft deform-able structures based on alginate hydrogels.

关键词： Alginate hydrogels Ultra-low modulus lung tissue-mimicking materials

Non-Resonant Structure Design of Catenary Transformer in Ultrasonic Gear Honing

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Wuhan University Journal of Natural Sciences 2012年第1期17卷 67-72页

作者： li xiangpeng ZHANG Chunhui WANG Shiying College of Mechanical Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina

To solve the design problem of transformer composed of non-resonant structure in ultrasonic gear-honing, force coupling conditions for moderately thick annular plate （MTAP） and catenary horn are proposed, and the frequency equations of the transformer, which consist of an MTAP and a catenary horn, are derived based on Mindlin＇s theory. The design parameters of the transformer were obtained by solving the frequency equations with the help of MATLAB, and its mode and frequency were deduced by the modal analysis of finite element method （FEM）, which are consistent with the theoretical design demands. The transformer design can be extended from system with thin annular plate to that with MTAP as the theoretical method by the simulation analysis of various ratios of the thickness to radius.

关键词： ultrasonic gear honing moderately thick annular plate (MTAP) Mindlin's theory catenary transformer

Effect of Relative Humidity on Resuspended Particles Caused by Human Walking

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Journal of Shanghai Jiaotong university(Science) 2020年第3期25卷 365-371页

作者： ZHENG Shuihua DU Weiyuan ZHAO lipan li xiangpeng College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China

The goal of this study is to investigate the effects of relative humidity on particle *** experimental study on the resuspension of different size particles is performed in the laboratory at 50%,60%,70% and 80% relative humidity *** material of flooring is shaggy *** experiments are carried out in a closed room with four laser dust instruments and a laser dust particle *** results show that when the relative humidity is 60% and 70%,the resuspension of indoor particulate matter is likely to *** walking has a greater impact on larger-size *** the conditions of different humidity,four situations all follow a rule that the larger the particle size is,the more stable the particle state is.

关键词： particulate matter resuspension relative humidity suspension rate human walking

Power of SAR Imagery and Machine Learning in Monitoring Ulva prolifera:A Case Study of Sentinel-1 and Random Forest

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Chinese Geographical Science 2024年第6期34卷 1134-1143页

作者： ZHENG Longxiao WU Mengquan XUE Mingyue WU Hao liANG Feng li xiangpeng HOU Shimin liU Jiayan College of Resources and Environmental Engineering Ludong UniversityYantai 264039China North China Sea Marine Forecasting and Hazard Mitigation Center Ministry of Natural ResourcesQingdao 266061China School of life Sciences Lanzhou UniversityLanzhou 730000China Marine Development and Fisheries Bureau of Yantai Yantai 264039China Modern Marine Industry Development Promotion Center of Yantai Yantai 264003China

Automatically detecting Ulva prolifera(***)in rainy and cloudy weather using remote sensing imagery has been a long-standing ***,we address this challenge by combining high-resolution Synthetic Aperture Radar(SAR)imagery with the machine learning,and detect the *** of the South Yellow Sea of China(SYS)in *** findings indicate that the Random Forest model can accurately and robustly detect ***,even in the presence of complex ocean backgrounds and speckle *** inspection confirmed that the method successfully identified the majority of pixels containing *** without misidentifying noise pixels or seawater pixels as ***,the method demonstrated consistent performance across different im-ages,with an average Area Under Curve(AUC)of 0.930(+0.028).The analysis yielded an overall accuracy of over 96%,with an average Kappa coefficient of 0.941(+0.038).Compared to the traditional thresholding method,Random Forest model has a lower estimation error of 14.81%.Practical application indicates that this method can be used in the detection of unprecedented *** in 2021 to derive continuous spatiotemporal *** study provides a potential new method to detect *** and enhances our under-standing of macroalgal outbreaks in the marine environment.

关键词： Ulva prolifera Random Forest Sentinel-1 Synthetic Aperture Radar(SAR)image machine learning remote sensing Google Earth Engine South Yellow Sea of China

Variable stiffness wires based on magnetorheological liquid metals

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International Journal of Smart and Nano Materials 2022年第2期13卷 232-243页

作者： Xiangbo Zhou Jian Shu Hu Jin Hongtai Ren Gang Ma Ning Gong Duan Ge Juan Shi Shi-Yang Tang Guolin Yun Hongda Lu Shuai Dong xiangpeng li Shiwu Zhang Weihua li CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefeiAnhuiChina School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongNSWAustralia Department of Electronic Electrical and Systems EngineeringSchool of EngineeringUniversity of BirminghamBirminghamUK College of Mechanical and Electrical Engineering Soochow UniversitySuzhouJiangsuChina

Magnetorheological fluid(MRF)has shown its great potential in the development of large mechanical devices,such as dampers,shock absorbers,rotary brakes,clutches,and prosthetic ***,more research focus has been invested on using MRF to develop soft,stretchable,and miniaturized devices with variable stiffness for realizing functionalities that cannot be achieved using solid smart ***,based on liquid metal magnetoactive slurries(LMMS),a variable stiffness wire with excellent electrical conductivity is *** exposure to a magnetic field,the LMMS wire has an extremely low stiffness,and can be easily stretched while maintaining an excellent electrical *** applying a magnetic field,the wire becomes much stiffer and can retain its shape even under a *** combination of properties of flexibility,high electrical conductivity,and variable stiffness of the wire is harnessed to make a flexible gripper that can grasp objects of various ***,by using gallium instead of its liquid metal alloys,the tunable stiffness range of the LMMS wire is signifi-cantly enhanced and can be controlled using both external magnetic fields and temperature-induced phase *** presented LMMS wire has the potential to be applied in flexible electronics,soft robotics and so on.

关键词： liquid metal magnetorheological fluid(MRF) various stiffness stretchable electronics soft robotics

逆向气流对规整填料表面液膜流体动力学特性的影响

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化工学报 2013年第9期64卷 3130-3138页

作者：李相鹏郑水华浙江工业大学化工机械设计研究所浙江杭州310032

为研究气相流量对规整填料内气液两相逆流流动情况下流场结构及界面行为的影响,建立了基于分离涡模拟(DES)方法与VOF模型相结合的CFD分析模型,VOF控制方程离散采用显示差分格式,体积分数离散采用界面重构方法。计算域整体采用结构化曲... 详细信息

为研究气相流量对规整填料内气液两相逆流流动情况下流场结构及界面行为的影响,建立了基于分离涡模拟(DES)方法与VOF模型相结合的CFD分析模型,VOF控制方程离散采用显示差分格式,体积分数离散采用界面重构方法。计算域整体采用结构化曲线网格(贴体网格)划分,并对局部进行了细化。结果表明,气相F因子较小时(F≤1.354Pa0.5),液膜自由表面及其纵向速度分量(vy)均呈周期性规律分布,波动幅度基本一致,而vy均为负值。F=3.386Pa0.5时,液膜自由表面波动出现紊乱,幅值差异明显增大,而界面液膜vy值仍基本呈周期性规律分布,在液相波峰下沿出现vy>0的情况。F=5.418Pa0.5时,出现液相返混,气相和液相内均出现大小不等的回流区并随液相返混过程发展演化,同时局部液膜出现整体向上流动特征。F≥6.772Pa0.5后,填料下部出现干板区,底部出口不再有液相流出。随气相F因子增大,持液量和有效界面传质面积均先增后减。

关键词：逆流气液两相流规整填料分离涡模拟流体动力学特性 F因子

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基于迭代控制搜索策略的分形图像压缩算法

华中科技大学学报（自然科学版） 2020年第7期48卷 1-6页

作者：郑运平李祥鹏华南理工大学计算机科学与工程学院

针对分形图像压缩算法编码时间较长的问题,提出了一种基于迭代控制搜索策略的快速分形图像压缩(ICSS)算法.当值域块寻找匹配的定义域块时,通过分形码的迭代更新次数来控制搜索过程,设置搜索终止条件,去除搜索过程中的低效搜索和无效搜索... 详细信息

针对分形图像压缩算法编码时间较长的问题,提出了一种基于迭代控制搜索策略的快速分形图像压缩(ICSS)算法.当值域块寻找匹配的定义域块时,通过分形码的迭代更新次数来控制搜索过程,设置搜索终止条件,去除搜索过程中的低效搜索和无效搜索;同时计算图像块相似度时采用等距采样图像进行降维处理,进一步降低计算复杂度.实验结果表明:与经典算法文献算法相比,本文算法在保持图像压缩比不变的情况下,能获得更好的重建图像质量,且编码速度显著提升.

关键词：分形图像压缩迭代控制图像降维搜索策略图像块相似度

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动态负载均衡算法在校园网格中的应用

微计算机信息 2006年第8X期22卷 164-165,155页

作者：李相朋武汉科技学院

校园网格能有效消除信息孤岛,实现我国高校的计算资源和信息资源的有效共享。一个亟待解决的问题是在校园网格环境下,服务器节点响应能力低下。目前已提出多种技术与方案以解决并提高校园网格的服务器节点的响应能力,负载均衡技术就是... 详细信息

校园网格能有效消除信息孤岛,实现我国高校的计算资源和信息资源的有效共享。一个亟待解决的问题是在校园网格环境下,服务器节点响应能力低下。目前已提出多种技术与方案以解决并提高校园网格的服务器节点的响应能力,负载均衡技术就是一种全新的技术。本文根据校园网格的特点和影响负载均衡的因素,对基于校园网格的负载均衡技术进行了分析和探讨,并提出一种动态负载均衡算法。

关键词：校园网格负载均衡动态权值