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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+

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Dynamic Stability and Fuzzy Reliability Analysis of Toppling Perilous Rock Under Seismic Excitation

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Journal of Earth Science 2024年第1期35卷 248-262页

作者： Linfeng Wang Jixu Zhang Wanchun Xia Xiaoming Huang Guojin Tan Key Laboratory of Geological Hazards Mitigation for Mountainous Highway and Waterway Chongqing Jiaotong UniversityChongqing 400074China School of transportation Southeast UniversityNanjing 211189China college of transportation Jilin UniversityChangchun 130012China

To predict the occurrence of the collapse disaster in toppling perilous rock under the action of bidirectional earthquakes,the dynamic stability and fuzzy reliability calculation method of toppling perilous rock under the action of bidirectional earthquakes is ***,the mass viscoelasticity model is used to simulate two main control surfaces of toppling perilous rock,the seismic dynamic response model and motion equation of toppling perilous rock are established based on the D'Alembert principle,and the Newmark-β method is used to solve the dynamic motion ***,the instability event of toppling perilous rock is considered a fuzzy event,the membership function expression of the stability coefficient of toppling perilous rock is determined based on the fuzzy failure criterion,the calculation equations of the toppling perilous rock dynamic stability coefficient and fuzzy reliability are established,and the fuzzy reliability evaluation method based on the probability distribution of reliability is ***,the influence of different superposition modes of seismic excitation on the fuzzy reliability of toppling perilous rock is *** calculation results of toppling perilous rock in the engineering case show that the fuzzy reliability calculated after considering the fuzzy failure criterion is reduced by 10.73% to 25.66% compared with the classical *** the bidirectional seismic excitation,the fuzzy reliability of toppling perilous rock is reduced by 5.46% to 14.89%.Compared with using the acceleration peak time encounter mode to superpose the seismic excitation,the fuzzy reliability of toppling perilous rock is reduced by 3.4% when the maximum action effect time encounter mode is adopted.

关键词： toppling perilous rock bidirectional earthquake fuzzy failure criterion dynamic stability fuzzy reliability Newmark-βmethod probability distribution function

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Characterization of Nutrients,Heavy Metals,Petroleum and Their Impact on Phytoplankton in Laizhou Bay:Implications for Environmental Management and Monitoring

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Journal of ocean University of China 2024年第3期23卷 822-834页

作者： WANG Kai ZHAO Linlin ZHU Yugui YANG Liqiang WANG Yunfeng HONG Xuguang college of Marine Life Science Ocean University of ChinaQingdao 266003China First Institute of oceanography Ministry of Natural ResourcesQingdao 266061China college of Fisheries Ocean University of ChinaQingdao 266003China Institute of oceanology Chinese Academy of SciencesQingdao 266071China Southern Marine Science and engineering Guangdong Laboratory Guangzhou 511458China

The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental *** study provides a comprehensive characterization of nutrients,petroleum,heavy metals,and phytoplankton community structure across seven distinct areas in *** results indicate relatively high concentrations of NO_(2)-N,SiO_(4)-Si,and NO_(3)-N in the Southwest Laizhou Bay(SWLB)and Huanghe River Estuary(HRE).In contrast,the East Laizhou bay(ELB)and the North of Huanghe River Estuary(NHRE)exhibit the highest concentrations of heavy metals(As,Cr and Hg).The areas with high phytoplankton density and community diversity are mainly located in the *** adjusting for basic environmental factors,phytoplankton density and Margalef richness index D are significantly associated with nutrients(NO_(3)-N,NO_(2)-N,NH_(4)-N,SiO_(4)-Si),and heavy metal(Cr)*** highlight that,in addition to Xiaoqinghe River,nutrients brought by the Mihe River in the SWLB and heavy metal(Cr)pollution in the ELB resulting from industrial and mining activities along the coast significantly influence phytoplankton growth and community ***,it is recommended that more monitoring and management efforts be focused on these regions in the future.

关键词： Huanghe River Estuary Laizhou Bay nutrients heavy metals phytoplankton biodiversity

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Sea cucumber derived sulfated sterols alter glucose metabolism by promoting gluconeogenesis and reducing glycogenesis in healthy mice

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Food Science and Human Wellness 2024年

作者： Shanyun Yu Teng Wang Yingcai Zhao Xiaoyue Li Changhu Xue Yuming Wang Tiantian Zhang SKL of Marine Food Processing & Safety Control college of Food Science and engineering ocean University of China Sanya Institute of oceanography ocean University of China

Sea cucumber derived sulfated sterols (SS) significantly ameliorated insulin resistance and decreased lipid accumulation compared to plant sterols. Interestingly， our recent study found that intervention with sea cucumber sulfated sterols could significantly increase blood glucose levels of healthy mice in the presence of glucose， while cholesterol sulfate， as one of sulfated sterols， did not have the same effect. However， the exact mechanism of SS on glucose metabolism is still unknown. In the present study， we investigated the potential mechanism by which SS influenced blood glucose homeostasis in healthy mice. Results showed that intervention with sea cucumber sulfated sterols did not affect the levels of hormones related to glucose metabolism， while led to a significant decrease in the synthesis of liver glycogen and muscle glycogen. Besides， the expression of proteins associated with the promotion of gluconeogenesis dramatically increased in the mice intervened with sea cucumber sulfated sterols. These findings suggested that sea cucumber sulfated sterols might change blood glucose metabolism in healthy mice by reducing glycogenesis and promoting gluconeogenesis.

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The Analysis of the Correlation between SPT and CPT Based on CNN-GA and Liquefaction Discrimination Research

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Computer Modeling in engineering & Sciences 2024年第2期138卷 1159-1182页

作者： Ruihan Bai Feng Shen Zihao Zhao Zhiping Zhang Qisi Yu Key Laboratory of the Ministry of Education for Geomechanics and Embankment engineering College of Civil and Transportation EngineeringHohai UniversityNanjing210098China School of Civil engineering Suzhou University of Science and TechnologySuzhou215011China School of Civil engineering Shenyang Jianzhu UniversityShenyang110168China college of Civil engineering Tongji UniversityShanghai200092China

The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires field testing and canbe time-consuming and labor-intensive. In contrast, the cone penetration test (CPT) provides a more convenientmethod and offers detailed and continuous information about soil layers. In this study, the feature matrix based onCPT data is proposed to predict the standard penetration test blow count N. The featurematrix comprises the CPTcharacteristic parameters at specific depths, such as tip resistance qc, sleeve resistance f s, and depth H. To fuse thefeatures on the matrix, the convolutional neural network (CNN) is employed for feature extraction. Additionally,Genetic Algorithm (GA) is utilized to obtain the best combination of convolutional kernels and the number ofneurons. The study evaluated the robustness of the proposed model using multiple engineering field data *** demonstrated that the proposed model outperformed conventional methods in predicting N values forvarious soil categories, including sandy silt, silty sand, and clayey silt. Finally, the proposed model was employedfor liquefaction discrimination. The liquefaction discrimination based on the predicted N values was comparedwith the measured N values, and the results showed that the discrimination results were in 75% agreement. Thestudy has important practical application value for foundation liquefaction engineering. Also, the novel methodadopted in this research provides new ideas and methods for research in related fields, which is of great academicsignificance.

关键词： CNN liquefaction discrimination SPT CPT

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Mechanical properties and energy evolution of Beishan shallow-layer granite under different unloading paths

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Journal of Mountain Science 2024年第5期21卷 1728-1744页

作者： WANG Chuanle LI Erbing ZHANG Dengke HAN Yang LU Hui HE Kang DU Guangyin School of transportation Southeast UniversityNanjing 211189China college of Defense engineering Army Engineering University of PLANanjing 210007China Nanjing Urban Construction Management Group Co. Ltd.Nanjing 210006China college of Field engineering Army Engineering University of PLANanjing 210007China

Rock has mechanical characteristics and a fracture damage mechanism that are closely related to its loading history and loading path. The mechanical properties, fracture damage features, acoustic emission(AE) characteristics, and strain energy evolution of the Beishan shallow-layer granite used in triaxial unloading tests were investigated in this study. Three groups of triaxial tests, namely, conventional triaxial compression test(Group Ⅰ), maintaining deviatoric stress synchronously unloading confining pressure test(Group Ⅱ), and loading axial pressure synchronously unloading confining pressure test(Group Ⅲ), were carried out for the cylindrical granite specimens. AE monitoring device was utilized in these tests to determine the degree to which the AE waves and AE events reflected the degree of rock damage. In addition, the crack stress thresholds of the specimens were determined by volumetric strain method and AE parameter method, and strain energy evolution of the rock was explored in different damage stages. The results show that the shallow-layer granite experiences brittle failure during the triaxial loading test and unloading test, and the rock has a greater damage degree during the unloading test. The crack stress thresholds of these samples vary greatly between tests, but the threshold ratios of all samples are similar in the same crack damage stage. The Mogi-Coulomb strength criterion can better describe the unloading failure strength of the rock. The evolution of the AE parameter characteristics and strain energy differs between the specimens used in different stress path tests. The dissipative strain energy is the largest in Group Ⅱ and the smallest in Group Ⅰ.

关键词： Beishan granite Unloading test Mechanical properties Damage mechanism Acoustic emission Strain energy

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Experimental and simulation research on hollow AZ31 magnesium alloy three-channel joint by hot extrusion forming with sand mandrel

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Journal of Magnesium and Alloys 2024年第1期12卷 98-109页

作者： Shi Shengnan Wang Hongyu Teng Fei Jiang Lei Sun Juncai Sun Jie Zhang Shunhu transportation engineering college Dalian Maritime UniversityDalianLiaoning 106026China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyangLiaoning 110819China Shagang School of Iron and Steel Soochow UniversitySuzhouJiangsu 215021China

Magnesium alloy is one of the lightest metal structural *** weight is further reduced through the hollow ***,the hollow structure is easily damaged during *** order to maintain the hollow structure and to transfer the stresses during the high temperature deformation,the sand mandrel is *** this paper,the hollow AZ31 magnesium alloy three-channel joint is studied by hot extrusion *** as one of solid granule medium is used to fill the hollow magnesium *** extrusion temperatures are 230℃ and 300℃,*** process parameters(die angle,temperature,bottom thickness,sidewall thickness,edge-to-middle ratio in bottom,bottom shape)of the hollow magnesium alloy are analyzed based on the results of experiments and the finite element *** results are shown that the formability of the hollow magnesium alloy will be much better when the ratio of sidewall thickness to the bottom thickness is 1:*** when edge-to-middle ratio in bottom is about 1:1.5,a better forming product can be *** best bottom shape in these experiments will be convex based on the forming *** grain will be refined obviously after the *** the microstructures will be shown as *** these lines will be well agreement with the mold in the corner.

关键词： AZ31 magnesium alloy Three-channel joint Sand Experiments and the finite element Die angle

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Urban Flood Mitigation Strategies with Coupled Gray–Green Measures: A Case Study in Guangzhou City, China

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International Journal of Disaster Risk Science 2024年第3期15卷 467-479页

作者： Jiayue Li Jiajun Zeng Guoru Huang Wenjie Chen School of Civil engineering and transportation South China University of Technology School of Architecture South China University of Technology State Key Laboratory of Subtropical Building and Urban Science South China University of Technology college of Water Conservancy and Civil engineering South China Agricultural University

The integration of gray and green infrastructure has proven to be a feasible approach for managing stormwater in established urban areas. However, evaluating the specific contributions of such coupled strategies is challenging. This study introduced a novel integrated hydrological-hydrodynamic model that takes into account the layout of low-impact development(LID)facilities along with pipeline alignment and rehabilitation. Reliable results from modeling were used to assess the individual contribution of LID and improved drainage facilities to urban flooding mitigation. We selected a natural island in Guangzhou City, China, as the study site. The results indicate that combining three LID measures, namely green roofs, sunken green spaces, and permeable pavements, can reduce total runoff by 41.7% to 25.89% for rainfall recurrence periods ranging from 1year to 100 years, and decrease the volume of nodal overflow by nearly half during rainfall events of less than 10-year return period. By integrating LID measures with the upgraded gray infrastructure, the regional pipeline overloading condition is substantially alleviated, resulting in a significant improvement in pipeline system resilience. For urban flooding control, it is recommended to integrate sufficient green space and avoid pipe-laying structural issues during urban planning and construction. The findings may assist stakeholders in developing strategies to best utilize gray and green infrastructure in mitigating the negative eff ects of urban flooding.

关键词： Coupled hydrodynamic model Gray–green approach Guangzhou City LID Pipe renovation Urban inundation

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Restoring cellular calcium homeostasis to rescue ER stress by 1,2-bis(2-aminophenoxy)ethane-N,N,N’,N’-tetraacetic acid acetoxymethyl ester-loaded lipid-mPLGA hybrid-nanoparticles for acute kidney injury therapy

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Chinese Chemical Letters 2024年第3期35卷 337-345页

作者： Jingwen Zhang Jiahui Yan Yanan Wang Hong Liu Xueping Sun Yuchao Gu Liangmin Yu Changcheng Li Jun Wu Zhiyu He Frontiers Science Center for Deep ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China college of Chemistry and Chemical engineering Ocean University of ChinaQingdao 266100China School of Medicine and Pharmacy Ocean University of ChinaQingdao 266003China Sanya oceanographic Institution Ocean University of ChinaQingdao 572024China Bioscience and Biomedical engineering Thrust The Hong Kong University of Science and Technology(Guangzhou)NanshaGuangzhou 511400China Division of Life Science The Hong Kong University of Science and TechnologyHong Kong 999077China

Early pathogenesis of ischemia-reperfusion(I/R)-induced acute kidney injury(AKI)is dominated by intracellular calcium overload,which induces oxidative stress,intracellular energy metabolism disorder,inflammatory activation,and a series of pathologic cascaded reactions that are closely intertwined with self-amplifying and interactive feedback loops,ultimately resulting in cell damage and kidney ***,most nanomedicines originate from the perspective of antioxidant stress,which can only quench existing reactive oxide species(ROS)but cannot prevent the continuous production of ROS,resulting in insufficient *** a safe and promising drug,BAPTA-AM is hydrolyzed into BAPTA by intracellular esterase upon entering cells,which can rapidly chelate with overloaded Ca^(2+),restoring intracellular calcium homeostasis,thus inhibiting ROS regeneration at the ***,we designed a KTP-targeting peptide-modified yolk-shell structure of liposome–poly(ethylene glycol)methyl ether-block-poly(L-lactide-co-glycolic)(mPLGA)hybrid nanoparticles(<100 nm),with the characteristics of high encapsulation rate,high colloid stability,facile modification,and prolonged blood circulation *** the BA/mPLGA@Lipo-KTP was targeted to the site of kidney injury,the cholesteryl hemisuccinate(CHEMS)in the phospholipid bilayer,as an acidic cholesterol ester,was protonated in the simulated inflammatory slightly acidic environment(pH 6.5),causing the liposomes to rupture and release the BA/mPLGA nanoparticles,which were then depolymerized by intracellular *** BAPTA-AM was diffused and hydrolyzed to produce BAPTA,which can rapidly cut off the malignant loop of calcium overload/ROS generation at its source,blocking the endoplasmic reticulum(ER)apoptosis pathway(ATF4–CHOP–Bax/Bcl-2,Casp-12–Casp-3)and the inflammatory pathway(TNF-α–NF-κB–IL-6 axes),thus alleviating pathological changes in kidney tissue,thereby inhibiting the expression of renal tubular marker kidney injury mole

关键词： BAPTA-AM Calcium overload Acid-responsive AKI ER stress

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Experimental Study on the Sinking and Leveling of A Large-Capacity Offshore Wind Turbine Five-Bucket Foundation in Sand

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China ocean engineering 2024年第4期38卷 586-601页

作者： LIAN Ji-jian ZHU Hang GUO Yao-hua WANG Hai-jun YU Tong-shun State Key Laboratory of Hydraulic engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil engineering Tianjin UniversityTianjin 300072China Tianjin University of Technology Tianjin 300384China college of engineering Ocean University of ChinaQingdao 266100China

As offshore wind farms expand into deeper and farther ocean regions and the unit capacity of offshore wind turbines(OWTs)increases,there is a pressing need for a new foundation structure that can accommodate deep-sea conditions and support large capacities while maintaining economical and *** meet this goal of integrated transportation and one-step installation,a novel five-bucket jacket foundation(FBJF),with its suction installation and leveling methods in sand,has been proposed,analyzed and experimentally ***,seepage failure experiments of the FBJF at various depths were conducted,and a formula for calculating the critical suction of seepage failure suitable for the FBJF in sand was chosen and recommended for use with a range of values for the permeability coefficient ***,through leveling experiments of the FBJF at different depths,the maximum adjustable leveling angle during the sinking process was defined using seepage failure and the adjustable leveling angle of the foundation as control *** leveling control strategies were proposed and ***,an automatic sinking and leveling control system for the FBJF was developed and experimentally verified for feasibility.

关键词： offshore wind turbine(OWT) bucket foundation seepage failure suction installation

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