检索结果-内蒙古大学图书馆

10th Australasian Congress on Applied Mechanics, ACAM 2021

作者： Chen, Liujie Yao, Haodong Ng, Ching Tai Fu, Jiyang School of Civil Engineering Guangzhou University Guangdong Guangzhou China MOE Key Lab of Disaster Forecast and Control in Engineering Guangdong Guangzhou China School of Civil Environmental & Mining Engineering The University of Adelaide SA Australia Research Center for Wind Engineering and Engineering vibration Guangzhou University Guangdong Guangzhou China

ISBN: (纸本)9781925627596

Crack is an important indication for assessing the condition and safety of concrete structures. Quick and accurate crack feature extraction and classification performance of deep learning model are important in crack classification. Therefore, this study proposed a crack classification method based on the modified lightweight neural network. The proposed method uses MobileNetV3-Large pre-trained using an ImageNet dataset as backbone and then adopts the Convolution Block Attention Module (CBAM), which contains two modules, Channel Attention Module and Spatial Attention Module. Without increasing the number of model parameters, CBAM can strengthen the ability of the neural network in crack feature extraction. The image dataset of concrete structures for verifying the proposed method contains four different types of cracks: transverse cracks, vertical cracks, diagonal cracks, and irregular cracks. Other deep learning models, such as MobileNetV3-Large, VGG16, EfficentNetB0, GoogLeNet, Efficentnetv2-S, are also used for the crack classification in this study and the results are compared with those obtained by the proposed method. The results demonstrate that the proposed method has the best performance with the minimum training time at 100 images/s and prediction time at 47.6 images/s, Accuracy of 95.93%, Precision of 95.95%, Recall of 95.95%, and Macro-F1 of 96.20%. The results indicate that the proposed method can effectively improve the accuracy of crack recognition and classification. It can also strengthen the ability of the network in extracting the complex crack image features. The proposed method can be applied practically for automatic crack detection. © ACAM 2021. All rights reserved.

关键词： Concrete buildings

来源：评论

学校读者我要写书评

暂无评论

Residual stress analysis of laser welding between output needle and helix 7

Residual stress analysis of laser welding between output nee...

引用

2020 7th International Conference on Computer-Aided Design, Manufacturing, Modeling and Simulation, CDMMS 2020

作者： Su, Wei Luo, Wenhao Dong, Xianshan Liu, Renhuai MOE Key Lab of Disaster Forecast and Control in Engineering Guangzhou510632 China Sci. and Technol. on Reliability Phys. and Application Technology of Electronic Component Laboratory China Electronic Product Reliability and Environmental Testing Research Institute Guangzhou510610 China School of Mechanics and Construction Engineering Jinan University Guangzhou510632 China

In order to obtain the welding stress of the output needle and helix, a finite element model is established and the mesh at the weld is refined to evaluate the welding residual stress. ANSYS parameter design language is used to simulate the motion load of welding heat source. Based on the exact calculation of the temperature field, the corresponding thermal units are converted into structural units to calculate the welding residual stress. Finally, the thermal stress distribution curve and residual stress distribution trend are obtained after post-treatment. © 2021 Institute of Physics Publishing. All rights reserved.

关键词： Residual stresses

来源：评论

学校读者我要写书评

暂无评论

Computer transient simulation for dual in-line package through finite element analysis and ANASYS software 3

Computer transient simulation for dual in-line package throu...

引用

3rd International Conference on Electrical, Communication and Computer engineering, ICECCE 2021

作者： Su, Wei Luo, Wenhao Dong, Xianshan Chen, Si Tomar, Agam Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory China Electronic Product Reliability and Environmental Testing Research Institute Guangzhou China MOE Key Lab of Disaster Forecast and Control in Engineering Guangzhou China School of Mechanics and Construction Engineering Jinan University Guangzhou China Faculty of Engineering and Mathematical Sciences University of Western Australia Australia

The reliability of the DIP package is studied by numerical simulation. Firstly, the DIP package, fixture and metal steel are modeled. Based on this, variable thickness papers are laid on the sample. According to the experiment, corresponding excitation and boundary condition are set. Then, the transient analysis result of DIP package is obtained through numerical simulation. The results show the relation of different thickness papers and acceleration-time curve, which provides a beneficial reference for the optimization of DIP packing. © 2021 Institute of Physics Publishing. All rights reserved.

关键词： Transient analysis

来源：评论

学校读者我要写书评

暂无评论

Finite element analysis of subsurface damage of optical glass after grinding 7

Finite element analysis of subsurface damage of optical glas...

引用

2020 7th International Conference on Computer-Aided Design, Manufacturing, Modeling and Simulation, CDMMS 2020

The interaction between abrasive particles and optical element surface can result in various forms of subsurface damage while removing the material. In order to obtain the stress distribution during optical glass grinding, the finite element analysis of optical glass grinding is carried out by using ANSYS software. The stress distribution of optical glass was obtained by establishing the grinding model of consolidated abrasive and free abrasive. The simulation results show that different abrasives have different damage degrees to the glass surface, which provides a useful reference for improving the quality of optical material processing technology. © 2021 Institute of Physics Publishing. All rights reserved.

关键词： Grinding (machining)

来源：评论

学校读者我要写书评

暂无评论

Harmonic response analysis for ball grid array package using computer finite element simulation 3

Harmonic response analysis for ball grid array package using...

引用

3rd International Conference on Electrical, Communication and Computer engineering, ICECCE 2021

BGA package is selected as the research object in this paper. Workbench (finite elemental analysis tool in ANSYS) is used for harmonic response analysis. The author lays several paper sheets on the sample and builds the finite element model of clamp, ceramic and metal plate. Then, the model analysis is carried out. Based on this, it is converted to harmonic response analysis. According to the results, the author has found that there is no relation between the number of paper sheets and acceleration-frequency result. It promotes the development of electronic packaging reliability. © 2021 Institute of Physics Publishing. All rights reserved.

关键词： Finite element method

来源：评论

学校读者我要写书评

暂无评论

Recycled Aggregate Concrete-Filled Steel Tube Columns with Small-Diameter Circular Frp-Confined Sea-Sand Concrete Cores: Conceptual and Experimental Investigations

SSRN

引用

SSRN 2023年

作者： Zeng, Lan Wu, Liqi Li, Boqin Fang, Shu Mohamed, Hazem Samih Fang, Zhuangcheng Yuan, Hong MOE Key Laboratory of Disaster Forecast and Control in Engineering School of Mechanics and Construction Engineering Jinan University Guangdong Guangzhou510632 China Guangdong Architectural Design and Research Institute Co. Ltd. Guangzhou510006 China Guangdong Key Laboratory of Earthquake Engineering & Applied Technique Earthquake Engineering Research & Test Centre Guangzhou University Guangzhou510006 China School of Architectural Engineering Guangzhou Institute of Science and Technology Guangzhou510540 China Fujian Agriculture and Forestry University China

Recycled aggregate concrete (RAC) prepared from waste concrete can achieve the green recycling of resources;however, its inferior material properties hinder its applications. Sea-sand concrete (SSC) can help alleviate the resource shortage of fresh water and river sands but is prone to steel corrosion. To address these challenges, this study developed a new RAC-filled steel tube column with a small-diameter circular fibre-reinforced polymer (FRP)-confined SSC core. This paper presents and discusses the results of the axial compression tests conducted on RAC-filled steel tube columns, with and without small-diameter circular FRP-confined SSC cores. The study investigated the effects of the configuration of the FRP-confined SSC core, diameter-to-thickness ratio of the FRP tubes, compressive strength of RAC and SSC, and cross-sectional shape of the column. The results revealed that using small-diameter circular FRP-confined SSC cores to partially replace RAC was effective in improving the compressive performance of RAC-filled steel tube columns. The increase in the number of FRP tubes, in-filled concrete strength, and confinement stiffness of the steel and FRP tubes contributed to improvements in the structural strength and ductility, resulting in progressive ladder-shaped declines in the post-peak curve. Finally, a reasonable load–capacity model is presented for the proposed columns. © 2023, The Authors. All rights reserved.

关键词： Steel corrosion

来源：评论

学校读者我要写书评

暂无评论

Flexural Performance of Layered Macro Fiber Reinforced Concrete Short Beams

SSRN

引用

SSRN 2022年

作者： Yuan, Hong Fu, Xiao-Hui Fan, Ya-Chen Fu, Bing Zou, Qi-Qi School of Mechanics and Construction Engineering Jinan University Guangzhou510632 China MOE Key Lab of Disaster Forecast and Control in Engineering Jinan University Guangzhou510632 China Department of Ocean Science and Engineering Southern University of Science and Technology Shenzhen518055 China

Fiber-reinforced polymer (FRP) composites have been increasingly used in various sectors, which inevitably results in an increasing amount of FRP waste to be dealt with. A recent study conducted by the author’s group explored a novel mechanical recycling method to process GFRP waste into small slender elements (referred to as "macro fibers") for reinforcing concrete, leading to so called "macro fibre reinforced concrete" (i.e., MFRC). The macro fibres recycled from waste FRP composites bridge the cracks in concrete and mitigate their development, thus enhancing the flexural strength and toughness of MFRC flexural members. However, the macro fibres have a negligible effect on the compressive properties of MFRC, which implies that the macro fibres in the compressive zone cannot be efficiently utilized. As motivated by the concept of the layered structure, this paper presents an experimental investigation on the flexural performance of the layered beams with the MFRC bottom layer and PC (plain concrete) top layer, expecting to improve the utilization of the incorporated macro fibres. The investigated test parameters include the height of the bottom layer as well as the macro fiber content in the bottom layer. The test results show that the application of layer structure effectively enhances the utilization of macro fibers and hence promotes the future technological application of the proposed mechanical recycling method. © 2022, The Authors. All rights reserved.

关键词： Fibers

来源：评论

学校读者我要写书评

暂无评论

Method of Analyzing Coating Structure Under Conical Concave Contact

SSRN

引用

SSRN 2022年

作者： Huang, Shi-Qing Tang, Pan-Jun Hou, Peng-Fei Zhang, Wen-Hua MOE Key Lab of Disaster Forecast and Control in Engineering Jinan University Guangzhou510632 China School of Mechanics and Construction Engineering Jinan University Guangzhou510632 China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha410082 China Department of Engineering Mechanics Hunan University Changsha410082 China

The evaluation of mechanical performance for a coating structure is important in the fields of mechanics and materials. The general theories of the contact mechanics for transversely isotropic elasticity coating structures under conical concave contact are presented in this paper. Based on the Green's function of semi-infinite bodies, the Green's function of coating structures are obtained with mirror image method. The general solution obtained indicates the displacement and stress at any position of the coating, substrate, and interface, which provide the code basis for the analysis of interface failure and determination of material parameters in numerical analysis software. This paper presents accurate solutions in the elastic stage, and there are stress singularities in the contact center and contact boundary, which provide a reference for future research on the relationships between stress singularities and plastic mechanical behavior. © 2022, The Authors. All rights reserved.

关键词： Finite element method

来源：评论

学校读者我要写书评

暂无评论

Abrupt emissions reductions during COVID-19 contributed to record summer rainfall in China (vol 13, pg 1, 2022)

引用

NATURE COMMUNICATIONS 2022年第1期13卷 959页

作者： Yang, Yang Ren, Lili Wu, Mingxuan Wang, Hailong Song, Fengfei Leung, L. Ruby Hao, Xin Li, Jiandong Chen, Lei Li, Huimin Zeng, Liangying Zhou, Yang Wang, Pinya Liao, Hong Wang, Jing Zhou, Zhen-Qiang Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology School of Environmental Science and Engineering Nanjing University of Information Science and Technology Nanjing Jiangsu China. yang.yang@***. Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology School of Environmental Science and Engineering Nanjing University of Information Science and Technology Nanjing Jiangsu China. Atmospheric Sciences and Global Change Division Pacific Northwest National Laboratory Richland WA USA. Atmospheric Sciences and Global Change Division Pacific Northwest National Laboratory Richland WA USA. hailong.wang@pnnl.gov. Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education Nanjing University for Information Science and Technology Nanjing Jiangsu China. Tianjin Key Laboratory for Oceanic Meteorology Tianjin Institute of Meteorological Science Tianjin China. Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan University Shanghai China.

Record rainfall and severe flooding struck eastern China in the summer of 2020. The extreme summer rainfall occurred during the COVID-19 pandemic, which started in China in early 2020 and spread rapidly across the globe. By disrupting human activities, substantial reductions in anthropogenic emissions of greenhouse gases and aerosols might have affected regional precipitation in many ways. Here, we investigate such connections and show that the abrupt emissions reductions during the pandemic strengthened the summer atmospheric convection over eastern China, resulting in a positive sea level pressure anomaly over northwestern Pacific Ocean. The latter enhanced moisture convergence to eastern China and further intensified rainfall in that region. Modeling experiments show that the reduction in aerosols had a stronger impact on precipitation than the decrease of greenhouse gases did. We conclude that through abrupt emissions reductions, the COVID-19 pandemic contributed importantly to the 2020 extreme summer rainfall in eastern China.

关键词： Atmospheric chemistry

来源：评论

学校读者我要写书评

暂无评论

Analysis of the Effect of Urban Geometric Form Factors on Heat Islands in Guangzhou

Analysis of the Effect of Urban Geometric Form Factors on He...

引用

2020 International Conference on Green Energy, Environment and Sustainable Development, GEESD 2020

作者： Zheng, Langtao Tang, Jian Chen, Xiong Guangdong Eng. Technology Research Center for Green Building Materials and Fabricated Architecture Maoming China MOE Key Laboratory of Disaster Forecast and Control in Engineering School of Mechanics and Construction Engineering Jinan University Guangzhou510632 China

The geometric form factors of urban space include height width ratio (H/W), sky view factor (SVF) and street direction, which directly affect the incidence of solar radiation, and then affect the temperature change of the block. In this study, the representative hot island and cold island streets in Guangzhou are selected as the research objects. According to the intensity and range distribution map of Guangzhou heat island in summer of 2014-2017 issued by Guangzhou Meteorological Bureau, the intersection area with high intensity of 4-year continuous heat island is found out by two-dimensional image superposition. In the region, the typical measurement points and comparison points are selected in groups, the temperature of each measurement point is monitored, and the urban geometry data is collected for comparative analysis. The results show that under the condition of the same underlying surface factor and no significant difference in artificial heat factor, the urban geometry can alleviate the heat island effect, and the measuring points with smaller sky view factor and larger height width ratio (H/W) have lower temperature, and the temperature of each measuring point has higher correlation with the size of SVF. In addition, the direction defined by the long axis of the valley will also affect the solar radiation equivalent of the street pavement, and the reclamation open land is also easy to become a heat island area. © Published under licence by IOP Publishing Ltd.

关键词： Landforms

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：