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Capsizing Probability of Dead Ship Stability in Beam Wind and Wave for Damaged Ship

China Ocean Engineering 2019年第2期33卷 245-251页

作者： HU Li-fen ZHANG Ke-zheng LI Xiao-ying CHANG Run-xin school of transporation Ludong University

The International Maritime Organization has developed the second-generation intact stability criteria. Thus, damage stability criteria can be established in the future. In order to identity the capsizing probability of damaged ship under dead ship condition, this paper investigates two methods that can be used to research the capsizing probability in time domain, which mainly focus on the nonlinear righting lever GZ curve solution. One method subjects the influence of damaged tanks on the hull shape down to the wind and wave, and the other method is consistent with the real-time calculation of the GZ curve. On the basis of one degree of freedom rolling equation, the solution is Monte Carlo method, and a damaged fishery bureau vessel is taken as a sample ship. In addition, the results of the time-domain capsizing probability under different loading conditions are compared and analyzed. The relation of GM and heeling angle with the capsizing probability is investigated, and its possible reason is analyzed. On the basis of combining the time-domain flooding process with the capsizing probability calculation, this research aims to lay the foundation for the study of capsizing probability in time domain under dead ship condition, as well as provide technical support for capsizing mechanism of dead ship stability and damage stability criteria establishment in waves.

关键词： damage stability criteria dead ship stability capsizing probability flooding process time domain

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Effect of Humidity Content and Morphology on the Properties of Proton Exchange Membrane from Sulfonated Poly (arylene ether sulfone) s Containing Fluorophenyl Pendant Groups

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Journal of Donghua University(English Edition) 2018年第3期35卷 237-243页

作者：李静谢娟李光 school of Traffic and transporation Engineering Changsha University of Science &Technology College of Materials Science and Engineering Donghua University

The characters of proton exchange membranes from sulfonated poly( aryl ether sulfone) s( SPAESs) containing fluorophenyl pendant groups are studied in this *** the water uptake and the water content parameter( λ) of all SPAES membranes increase almost linearly with sulfonation degree( SD)and *** being equilibrated in deionized water,the dimensional change in plane is much less affected by temperature than that in vertical *** all the humidity condition the proton conductivities of these SPAES membranes increase with SD and temperature.A maximus proton conductivity of 0.38 S/cm is attained at 90 ℃ for SPAES-5 with a SD of 99.3% when the membrane is fully hydrated,higher than that of Nafion *** the proton conductivities of SPAES membranes decrease dramatically with the relative humidity and all of them are lower and more affected by relative humidity than that of Nafion 115 at relative humidity lower than 100%,which may be due to the cumulative effects of narrower channels with spherical clusters for proton migration,more rigid chains and larger tortuosity of SPAESs.

关键词： fuel cell proton exchange membrane(PEM) proton conductivity humidity content morphology

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Precision Assessment of UAVRS Based DSM in Disaster Emergency

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Advances in Remote Sensing 2016年第3期5卷 203-213页

作者： Yumin Tan Lingfeng He Linjie Bai school of transporation Science & Engineering Beihang University Beijing China State Grid Corporation of China Shijiazhuang China

Ground control point (GCP) is important for georeferencing remotely sensed images and topographic model. However, considering that GCP collection is sometimes a difficult, time-consuming and expensive task with high resolution (HR) data in remote and harsh environments, today unmanned aerial vehicle based remote sensing (UAVRS) is frequently used in geological disaster emergency monitoring and rescuing for its great advantage in collecting timely onsite images. In this paper, for evaluating the feasibility of the UAVRS in disaster emergency and high cut slope safety monitoring, the digital surface model (DSM) without GCPs based on Structure from Motion (SfM) is accessed, and results showed that the geometric accuracy of DSM was smaller than 1 percent, which prove the usefulness of DSM based on UAVRS in emergency. Comparing to normal disaster emergency, the method without GCPs can be more efficient and save the disaster emergency time by neglecting GCPs measurement.

关键词： High Cut Slope Digital Surface Model (DSM) Slope Photography Geometric Accuracy Unmanned Aerial Vehicle (UAV)

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不同节理起伏角的非贯通岩样拉伸剪切过程声发射演化特征

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Journal of Central South University 2024年第5期31卷 1687-1699页

作者：潘浩岚胡杰戎晓力石少帅贺鹏徐一帆 school of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China school of Qilu transporation Shandong UniversityJinan 250061China Department of Civil Engineering Shandong University of Science and TechnologyQingdao 266590China

拉伸剪切破坏通常发生在深层现浇隧道施工过程中。本文利用自主研发的多功能岩石力学试验系统,对含有规则锯齿状节理的类岩试样进行直接拉伸剪切试验,研究节理起伏角度变化对拉伸剪切强度、温度和声发射的影响。结果表明,试样的峰值剪... 详细信息

拉伸剪切破坏通常发生在深层现浇隧道施工过程中。本文利用自主研发的多功能岩石力学试验系统,对含有规则锯齿状节理的类岩试样进行直接拉伸剪切试验,研究节理起伏角度变化对拉伸剪切强度、温度和声发射的影响。结果表明,试样的峰值剪切强度随着节理起伏角的增大而降低,节理起伏角的增大导致岩桥更容易拉伸破坏,同时也使裂缝轮廓呈现出明显的阶梯状特征。在接近失效时,试样都产生了强烈的声发射信号,并产生了更多的裂纹,同时伴随能量耗散和温度降低。在三个试样的加载过程中,声发射b值呈现出先增大后减小的总体趋势,在接近峰值强度时急剧下降。根据RAAF值对裂缝进行分类,结果显示,在初始加载过程中,裂缝主要为纯拉伸类型。当试样接近失效时,剪切裂纹和复合裂纹的数量明显增加。

关键词：节理岩样拉剪破坏节理起伏角声发射热红外

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Influence of loading ratio on flat slab connections at elevated temperature:A numerical study

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 664-674页

作者： Rwayda Kh.S.AL-HAMD Martin GILLIE Safaa Adnan MOHAMAD Lee S.CUNNINGHAM Mechanical Aerospace and Civil Engineering DepartmentSchool of EngineeringThe University of ManchesterManchester M139PLUK Prosthetics and Orthotics Engineering Deparment College of EngineeringAl-Nahrain UniversityBaghdad 10011Iraq Deparment of Mechanical and Consrruction Engineering Northumbria UniversityNewcastleNE18STUK Department of Highway and transporation Engineering Al-Mustansiriyah UniversityBaghdad 10011lraq

For reinforced concrete members subjected to high temperature,the degree of in-service loading,commonly expressed as the loading ratio,can be highly influential on the structural *** particular,the loading ratio may be pivotal in relation to the phenomenon of load-induced thermal *** its potentially pivotal role,to date,the influence of the loading ratio on both material and structural behavior has not been explored in *** practice,real structures experience variation in imposed loading during their service life and it is important to understand the likely response at elevated temperatures across the loading *** this paper,the effect of the loading ratio is numerically investigated at both material and structural level using a validated finite element *** model incorporates a proposed constitutive model accounting for load-induced thermal strain and this is shown to outperform the existing Eurocode 2 model in terms of *** the validated model,the specific case of flats slabs and the associated connections to supporting columns at various loading ratios are *** the cases examined,a marked difference in the structural behavior including displacement direction was captured from low to high loading ratios consistent with experimental observations.

关键词： concrete finite clements fire load-induced thermal strain punching shear

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Transfer learning-based encoder-decoder model with visual explanations for infrastructure crack segmentation:New open database and comprehensive evaluation

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Underground Space 2024年第4期17卷 60-81页

作者： Fangyu Liu Wenqi Ding Yafei Qiao Linbing Wang Illinois Center for transporation Department of Civil and Environmental EngineeringUniversity of Illinois Urbana-ChampaignIllinois 61801USA Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education Tongji UniversityShanghai 200092China school of Environmental CivilAgricultural and Mechanical EngineeringUniversity of GeorgiaGeorgia 30602USA

Contemporary demands necessitate the swift and accurate detection of cracks in critical infrastructures,including tunnels and *** study proposed a transfer learning-based encoder-decoder method with visual explanations for infrastructure crack ***,a vast dataset containing 7089 images was developed,comprising diverse conditions—simple and complex crack patterns as well as clean and rough ***,leveraging transfer learning,an encoder-decoder model with visual explanations was formulated,utilizing varied pre-trained convolutional neural network(CNN)as the *** explanations were achieved through gradient-weighted class activation mapping(Grad-CAM)to interpret the CNN segmentation ***,accuracy,complexity(computation and model),and memory usage assessed CNN feasibility in practical *** performance was gauged via prediction and visual *** investigation encompassed hyperparameters,data augmentation,deep learning from scratch *** learning,segmentation model architectures,segmentation model encoders,and encoder pre-training *** underscored transfer learning’s potency in enhancing CNN accuracy for crack segmentation,surpassing deep learning from ***,encoder classification accuracy bore no significant correlation with CNN segmentation *** all tested models,UNet-EfficientNet_B7 excelled in crack segmentation,harmonizing accuracy,complexity,memory usage,prediction,and visual explanation.

关键词： Crack segmentation Transfer learning Visual explanation Infrastructure Database

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Effects of Transportation on Antioxidant Status in Cynomolgus Monkeys(Macaca fascicularis)

Effects of Transportation on Antioxidant Status in Cynomolgu...

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第十三届中国实验动物科学年会

作者： Xueying Pan Liang Lu Xiancheng Zeng Yan Chang Xiuguo Hua Shanghai Key Laboratory of Veterinary Biotechnology School of Agriculture and BiologyShanghai Jiaotong University National Shanghai Center for New Drug Safety Evaluation&Research(NCDSER)

To evaluate the effects of transportation on oxidative stress in cynomolgus monkeys, the levels of serum reduced glutathione(GSH), malondialdehyde(MDA), and protein carbonyl(PC), and the activities of total antioxidant capacity(T-AOC), superoxide dismutase(SOD), glutathione peroxidase(GSH-Px), and catalase(CAT) in cynomolgus monkeys were examined at the pre-transportation(Day 0), on the day of arrival(Day 1), and on Days 7, 14, and 21 post-transportation. Compared with that on Day 0, T-AOC activity on Days 1, 7, and 14 post-transportation showed a significant decrease(Ptransporation. Decreases in the GSH, T-AOC, CAT, and SOD levels/activities and increases in the MDA, PC and GSH-Px levels/activities were observed in cynomolgus monkeys after transportation. These results suggested that transportation could result in imbalance of oxidant and antioxidant and excess oxidative stress in cynomolgus monkeys. Cynomolgus monkeys after transportation should have at least 21 days’ recovery to regain their healthy status.

关键词： cynomolgus monkeys transportation oxidative parameters,stress

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