检索结果-南通市图书馆

Automatic Road Tunnel Crack Inspection Based on Crack Area Sensing and Multiscale Semantic Segmentation

Computers, Materials & Continua 2024年第4期79卷 1679-1703页

作者： Dingping Chen Zhiheng Zhu Jinyang Fu Jilin He college of Mechanical and Electrical Engineering Central South UniversityChangsha410083China Department of Geotechnical Guangdong Hualu Transportation Technology Company LimitedGuangzhou510000China National Engineering Research Center of High-Speed railway Construction Technology Changsha410075China

The detection of crack defects on the walls of road tunnels is a crucial step in the process of ensuring travel safetyand performing routine tunnel maintenance. The automatic and accurate detection of cracks on the surface of roadtunnels is the key to improving the maintenance efficiency of road tunnels. Machine vision technology combinedwith a deep neural network model is an effective means to realize the localization and identification of crackdefects on the surface of road *** propose a complete set of automatic inspection methods for identifyingcracks on the walls of road tunnels as a solution to the problem of difficulty in identifying cracks during manualmaintenance. First, a set of equipment applied to the real-time acquisition of high-definition images of walls inroad tunnels is designed. Images of walls in road tunnels are acquired based on the designed equipment, whereimages containing crack defects are manually identified and selected. Subsequently, the training and validationsets used to construct the crack inspection model are obtained based on the acquired images, whereas the regionscontaining cracks and the pixels of the cracks are finely labeled. After that, a crack area sensing module is designedbased on the proposed you only look once version 7 model combined with coordinate attention mechanism (CAYOLOV7) network to locate the crack regions in the road tunnel surface images. Only subimages containingcracks are acquired and sent to the multiscale semantic segmentation module for extraction of the pixels to whichthe cracks belong based on the DeepLab V3+ network. The precision and recall of the crack region localizationon the surface of a road tunnel based on our proposed method are 82.4% and 93.8%, respectively. Moreover, themean intersection over union (MIoU) and pixel accuracy (PA) values for achieving pixel-level detection accuracyare 76.84% and 78.29%, respectively. The experimental results on the dataset show that our proposed two-staged

关键词： Road tunnel crack inspection crack area sensing multiscale semantic segmentation CA-YOLO V7 DeepLab V3+

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ratiometric fluorescence probe for accurate detection of Concanavalin A by coupling fluorescent microsphere with boric acid functionalized carbon dots

引用

Chinese Chemical Letters 2024年第2期35卷 460-463页

作者： Mingyue Xie Juan Chen Yufei Wang Bojun Liu Rong-Bin Song Hong-Min Meng Zhaohui Li college of Chemistry Institute of Analytical Chemistry for Life ScienceHenan Joint International Research Laboratory of Green Construction of Functional Molecules and their Bioanalytical ApplicationsZhengzhou UniversityZhengzhou 450001China Zhengzhou Key Laboratory of Forensic Science and Technology Railway Police CollegeZhengzhou 450053China School of Ecology and Environment Zhengzhou UniversityZhengzhou 450001China

Accurate and sensitive strategies for Concanavalin A(Con A)sensing are conducive to the better cognition of various important biological and physiological ***,by designing dextran-functionalized fluorescent microspheres(DxFMs)and boric acid-modified carbon dots(BCDs)as recognition unit and built-in signal reference respectively,a ratiometric fluorescent detection platform was proposed for Con A detection with high *** this protocol,the BCDs/DxFMs precipitation was formed due to the covalent interactions between cis-diol of DxFMs and boronic acid groups of BCDs,thus only fluorescence of BCDs could be detected in the *** Con A was presented,it could bind to DxFMs through its carbohydrate recognition ability and suppress the subsequent assembly between DxFMs and BCDs,leading to the simultaneous capture of DxFMs and BCDs fluorescence in the *** the BCDs content was superfluous,their fluorescence intensities were basically constant in all *** on the unchanged BCDs fluorescence signal and target-dependent DxFMs fluorescence signal in supernatant,the ratiometric detection of Con A was *** optimized conditions,this ratiometric fluorescent platform displayed a linear detection range from 0.125μg/mL to 12.5μg/mL with a detection limit of 0.089μg/***,satisfied analytical outcomes for Con A detection in serum samples were obtained,manifesting huge application potential of this ratiometric fluorescent platform in clinical diagnosis.

关键词： Concanavalin A Fluorescent microspheres Carbon dots Ratiometric fluorescent assay Reliability

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Stability analysis of tunnel face reinforced with face bolts

引用

Journal of Mountain Science 2024年第7期21卷 2445-2461页

作者： TIAN Chongming JIANG Yin YE Fei OUYANG Aohui HAN Xingbo SONG Guifeng School of highway Chang’an UniversityXi’an 710064China Civil Structural&Environmental EngineeringUniversity College CorkCork T12 YF78Ireland Yunnan Laman Expressway Co.Ltd. Xishuangbanna 666300China

Face bolting has been widely utilized to enhance the stability of tunnel face,particularly in soft soil ***,the influence of bolt reinforcement and its layout on tunnel face stability has not been systematically *** on the theory of linear elastic mechanics,this study delved into the specific mechanisms of bolt reinforcement on the tunnel face in both horizontal and vertical *** also identified the primary failure types of ***,a design approach for tunnel face bolts that incorporates spatial layout was established using the limit equilibrium method to enhance the conventional wedge-prism *** proposed model was subsequently validated through various means,and the specific influence of relevant bolt design parameters on tunnel face stability was ***,design principles for tunnel face bolts under different geological conditions were *** findings indicate that bolt failure can be categorized into three stages:tensile failure,pullout failure,and comprehensive *** cohesion,internal friction angle,bolt density,and overlap length can effectively enhance tunnel face *** to significant variations in stratum conditions,tailored design approaches based on specific failure stages are necessary for bolt design.

关键词： highway tunnels Tunnel face Face bolts Limit equilibrium method Slice method

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Multi-Body Dynamics Modeling of Heavy Goods Vehicle-Rail Interaction

引用

Open Journal of Applied Sciences 2024年第7期14卷 1715-1722页

作者： Lili Liu Jianhua Liu Jihong Zuo college of Intelligent Control Hunan Railway Professional Technology College Zhuzhou China college of Transportation Engineering Hunan University of Technology Zhuzhou China

Based on the principle of vehicle-track coupling dynamics, SIMPACK multi-body dynamics software is used to establish a C80 wagon line-coupled multi-body dynamics model with 73 degrees of freedom. And the reasonableness of the line-coupled dynamics model is verified by using the maximum residual acceleration, the nonlinear critical speed of the wagon. The experimental results show that the established vehicle line coupling dynamics model meets the requirements of vehicle line coupling dynamics modeling.

关键词： Vehicle-Rail Coupling Dynamic Modeling Wheel-Rail Interaction Forces

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Wind Speed Prediction Based on Improved VMD-BP-CNN-LSTM Model

引用

Journal of Power and Energy Engineering 2024年第1期12卷 29-43页

作者： Chaoming Shu Bin Qin Xin Wang college of railway Transportation Hunan University of Technology Zhuzhou China college of Electrical and Information Engineering Hunan University of Technology Zhuzhou China

Amid the randomness and volatility of wind speed, an improved VMD-BP-CNN-LSTM model for short-term wind speed prediction was proposed to assist in power system planning and operation in this paper. Firstly, the wind speed time series data was processed using Variational Mode Decomposition (VMD) to obtain multiple frequency components. Then, each individual frequency component was channeled into a combined prediction framework consisting of BP neural network (BPNN), Convolutional Neural Network (CNN) and Long Short-Term Memory Network (LSTM) after the execution of differential and normalization operations. Thereafter, the predictive outputs for each component underwent integration through a fully-connected neural architecture for data fusion processing, resulting in the final prediction. The VMD decomposition technique was introduced in a generalized CNN-LSTM prediction model;a BPNN model was utilized to predict high-frequency components obtained from VMD, and incorporated a fully connected neural network for data fusion of individual component predictions. Experimental results demonstrated that the proposed improved VMD-BP-CNN-LSTM model outperformed other combined prediction models in terms of prediction accuracy, providing a solid foundation for optimizing the safe operation of wind farms.

关键词： Wind Speed Forecast Long Short-Term Memory Network BP Neural Network Variational Mode Decomposition Data Fusion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research on Track Fastener Service Status Detection Based on Improved Yolov4 Model

引用

Journal of Transportation Technologies 2024年第2期14卷 212-223页

作者： Jing He Weiqi Wang Nengpu Yang college of Electrical and Information Engineering Hunan University of Technology Zhuzhou Hunan college of railway Transportation Hunan University of Technology Zhuzhou Hunan

As an important part of railway lines, the healthy service status of track fasteners was very important to ensure the safety of trains. The application of deep learning algorithms was becoming an important method to realize its state detection. However, there was often a deficiency that the detection accuracy and calculation speed of model were difficult to balance, when the traditional deep learning model is used to detect the service state of track fasteners. Targeting this issue, an improved Yolov4 model for detecting the service status of track fasteners was proposed. Firstly, the Mixup data augmentation technology was introduced into Yolov4 model to enhance the generalization ability of model. Secondly, the MobileNet-V2 lightweight network was employed in lieu of the CSPDarknet53 network as the backbone, thereby reducing the number of algorithm parameters and improving the model’s computational efficiency. Finally, the SE attention mechanism was incorporated to boost the importance of rail fastener identification by emphasizing relevant image features, ensuring that the network’s focus was primarily on the fasteners being inspected. The algorithm achieved both high precision and high speed operation of the rail fastener service state detection, while realizing the lightweight of model. The experimental results revealed that, the MAP value of the rail fastener service state detection algorithm based on the improved Yolov4 model reaches 83.2%, which is 2.83% higher than that of the traditional Yolov4 model, and the calculation speed was improved by 67.39%. Compared with the traditional Yolov4 model, the proposed method achieved the collaborative optimization of detection accuracy and calculation speed.

关键词： Yolov4 Model Service Status of Track Fasteners Detection and Recognition Data Augmentation Lightweight Network Attention Mechanism

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Remaining Useful Life Prediction of Rail Based on Improved Pulse Separable Convolution Enhanced Transformer Encoder

引用

Journal of Transportation Technologies 2024年第2期14卷 137-160页

作者： Zhongmei Wang Min Li Jing He Jianhua Liu Lin Jia college of railway Transportation Hunan University of Technology Zhuzhou Hunan college of Electrical and Information Engineering Hunan University of Technology Zhuzhou Hunan

In order to prevent possible casualties and economic loss, it is critical to accurate prediction of the Remaining Useful Life (RUL) in rail prognostics health management. However, the traditional neural networks is difficult to capture the long-term dependency relationship of the time series in the modeling of the long time series of rail damage, due to the coupling relationship of multi-channel data from multiple sensors. Here, in this paper, a novel RUL prediction model with an enhanced pulse separable convolution is used to solve this issue. Firstly, a coding module based on the improved pulse separable convolutional network is established to effectively model the relationship between the data. To enhance the network, an alternate gradient back propagation method is implemented. And an efficient channel attention (ECA) mechanism is developed for better emphasizing the useful pulse characteristics. Secondly, an optimized Transformer encoder was designed to serve as the backbone of the model. It has the ability to efficiently understand relationship between the data itself and each other at each time step of long time series with a full life cycle. More importantly, the Transformer encoder is improved by integrating pulse maximum pooling to retain more pulse timing characteristics. Finally, based on the characteristics of the front layer, the final predicted RUL value was provided and served as the end-to-end solution. The empirical findings validate the efficacy of the suggested approach in forecasting the rail RUL, surpassing various existing data-driven prognostication techniques. Meanwhile, the proposed method also shows good generalization performance on PHM2012 bearing data set.

关键词： Equipment Health Prognostics Remaining Useful Life Prediction Pulse Separable Convolution Attention Mechanism Transformer Encoder

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Failure evaluation and control factor analysis of slope block instability along traffic corridor in Southeastern Tibet

引用

Journal of Mountain Science 2024年第6期21卷 1830-1848页

作者： LIU Changqing BAO Han LAN Hengxing YAN Changgen LI Changbo LIU Shijie School of highway Chang'an UniversityXi'an 710064China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China college of Geological Engineering and Geomatics Chang'an UniversityXi'an 710054China

The instability of slope blocks occurred frequently along traffic corridor in Southeastern Tibet(TCST),which was primarily controlled by the rock mass structures.A rapid method evaluating the control effects of rock mass structures was proposed through field statistics of the slopes and rock mass structures along TCST,which combined the stereographic projection method,modified M-JCS model,and limit equilibrium *** instabilities of slope blocks along TCST were then evaluated rapidly,and the different control factors of instability were *** showed that the probabilities of toppling(5.31%),planar(16.15%),and wedge(35.37%)failure of slope blocks along TCST increased *** instability modes were respectively controlled by the anti-dip joint,the joint parallel to slope surface with a dip angle smaller than the slope angle(singlejoint),and two groups of joints inclined out of the slope(double-joints).Regarding the control effects on slope block instability,the stabilization ability of doublejoints(72.7%),anti-dip joint(67.4%),and single-joint(57.6%)decreased sequentially,resulting in different probabilities of slope block ***,nearby regional faults significantly influenced the joints,leading to spatial heterogeneity and segmental clustering in the stabilization ability provided by joints to the slope ***,the stability of slope blocks gradually weakened as they approached the fault *** paper can provide guidance and assistance for investigating the development characteristics of rock mass structures and the stability of slope blocks.

关键词： Slope engineering Block instability Rapid evaluation method Rock mass structure Control factor

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Age of Information Based User Scheduling and Data Assignment in Multi-User Mobile Edge Computing Networks:An Online Algorithm

引用

China Communications 2024年第5期21卷 153-165页

作者： Ge Yiyang Xiong Ke Dong Rui Lu Yang Fan Pingyi Qu Gang School of Computer and Information Technology Beijing Jiaotong UniversityBeijing 100044China Engineering Research Center of Network Management Technology for High Speed railway of Ministry of Education Beijing 100044China Beijing Engineering Research Center of High-speed railway Broadband Mobile Communications Beijing 100044China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Department of Electrical and Computer Engineering College ParkMarylandUSA

This paper investigates the age of information(AoI)-based multi-user mobile edge computing(MEC)network with partial offloading *** weighted sum AoI(WSA)is first analyzed and derived,and then a WSA minimization problem is formulated by jointly optimizing the user scheduling and data *** to the non-analytic expression of the WSA *** optimization variables and the unknowability of future network information,the problem cannot be solved with known solution ***,an online Joint Partial Offloading and User Scheduling Optimization(JPOUSO)algorithm is proposed by transforming the original problem into a single-slot data assignment subproblem and a single-slot user scheduling sub-problem and solving the two sub-problems *** analyze the computational complexity of the presented JPO-USO algorithm,which is of O(N),with N being the number of *** results show that the proposed JPO-USO algorithm is able to achieve better AoI performance compared with various baseline *** is shown that both the user’s data assignment and the user’s AoI should be jointly taken into account to decrease the system WSA when scheduling users.

关键词： age of information(aoi) mobile edge computing(mec) user scheduling

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Influences of the Fresh Air Volume on the Removal of Cough-Released Droplets in a Passenger Car of a High-Speed Train Using CFD

引用

Computer Modeling in Engineering & Sciences 2024年第3期138卷 2727-2748页

作者： Jun Xu Kai Bi Yibin Lu TiantianWang Hang Zhang Zeyuan Zheng Fushan Shi Yaxin Zheng Xiaoying Li Jingping Yang CRRC Changchun railway Vehicles Co. Ltd.Changchun130062China Key Laboratory of Traffic Safety on Track Ministry of EducationSchool of Traffic&Transportation EngineeringCentral South UniversityChangsha410075China college of Mechanical and Vehicle Engineering Hunan UniversityChangsha410082China

The spread and removal of pollution sources,namely,cough-released droplets in three different areas(front,middle,and rear areas)of a fully-loaded passenger car in a high-speed train under different fresh air flow volume were studied using computational fluid dynamics(CFD)*** addition,the structure of indoor flow fields was also *** results show that the large eddies are more stable and flow faster in the air supply under Mode 2(fresh air volume:2200m3/h)compared to Mode 1(fresh air volume:1100m3/h).By analysing the spreading process of droplets sprayed at different locations in the passenger car and with different particle sizes,the removal trends for droplets are found to be similar under the two air supply ***,when increasing the fresh air flow volume,the droplets in the middle and front areas of the passenger car are removed *** the droplets had dispersed for 60s,Mode 2 exhibited a removal rate approximately 1%–3%higher than Mode 1 for small and medium-sized droplets with diameters of 10 and 50μ*** those in the rear area,the situation is reversed,with Mode 1 slightly surpassing Mode 2 by 1%–3%.For large droplets with a diameter of 100μm,both modes achieved a removal rate of over 96%in all three regions at the 60 *** results can provide guidance for air supply modes of passenger cars of high-speed trains,thus suppressing the spread of virus-carrying droplets and reducing the risk of viral infection among passengers.

关键词： Cough-released pollutants CFD ventilation inside trains supply air volume

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

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

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

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

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

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：