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Underground Space 2024年第5期18卷 114-129页

作者： Haibo Hu Xunjian Hu Xiaonan Gong research center of Coastal and Urban Geotechnical engineering Zhejiang UniversityHangzhou 310058China

The application of steel strut force servo systems in deep excavation engineering is not widespread,and there is a notable scarcity of in-situ measured *** presents a significant research gap in the *** this,our study introduces a valuable dataset and application scenarios,serving as a reference point for future *** main objective of this study is to use machine learning(ML)methods for accurately predicting strut forces in steel supporting structures,a crucial aspect for the safety and stability of deep excavation *** employed five different ML methods:radial basis function neural network(RBFNN),back propagation neural network(BPNN),K-Nearest Neighbor(KNN),support vector machine(SVM),and random forest(RF),utilizing a dataset of 2208 measured *** points included one output parameter(strut forces)and seven input parameters(vertical position of strut,plane position of strut,time,temperature,unit weight,cohesion,and internal frictional angle).The effectiveness of these methods was assessed using root mean square error(RMSE),correlation coefficient(R),and mean absolute error(MAE).Our findings indicate that the BPNN method outperforms others,with RMSE,R,and MAE values of 72.1 kN,0.9931,and 57.4 kN,respectively,on the testing *** study underscores the potential of ML methods in precisely predicting strut forces in deep excavation engineering,contributing to enhanced safety measures and project planning.

关键词： Deep excavation Steel supporting structure Strut forces Machine learning Time Temperature

Residual stress modeling of mitigated fused silica damage sites with CO_(2)laser annealing

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Chinese Physics B 2024年第3期33卷 509-514页

作者：张传超廖威张丽娟蒋晓龙方振华蒋晓东 Laser Fusion research center China Academy of Engineering PhysicsMianyang 621900China

A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage *** proposed model extracts the residual strain from the differences in thermoelastic contraction of fused silica with different fictive temperatures from the initial frozen-in temperatures to ambient *** residual stress fields of mitigated damage sites for the CO_(2)laser-annealed case are obtained by a finite element analysis of equilibrium equations and constitutive *** simulated results indicate that the proposed model can accurately evaluate the residual stress fields of laser-annealed mitigated damage sites with a complex thermal *** calculated maximum hoop stress is in good agreement with the reported experimental *** estimated optical retardance profiles from the calculated radial and hoop stress fields are consistent with the photoelastic *** results provide sufficient evidence to demonstrate the suitability of the proposed model for describing the residual stresses of mitigated fused silica damage sites after CO_(2)laser annealing.

关键词： fused silica damage mitigation residual stress laser annealing

Surface Defect Detection and Evaluation Method of Large Wind Turbine Blades Based on an Improved Deeplabv3+Deep Learning Model

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Structural Durability & Health Monitoring 2024年第5期18卷 553-575页

作者： Wanrun Li Wenhai Zhao Tongtong Wang Yongfeng Du Institution of earthquake Protection and Disaster Mitigation Lanzhou University of TechnologyLanzhou730050China International research Base on Seismic Mitigation and Isolation of GANSU Province Lanzhou University of TechnologyLanzhou730050China Disaster Prevention and Mitigation engineering research center of Western Civil engineering Lanzhou University of TechnologyLanzhou730050China

The accumulation of defects on wind turbine blade surfaces can lead to irreversible damage,impacting the aero-dynamic performance of the *** address the challenge of detecting and quantifying surface defects on wind turbine blades,a blade surface defect detection and quantiﬁcation method based on an improved Deeplabv3+deep learning model is ***,an improved method for wind turbine blade surface defect detection,utilizing Mobilenetv2 as the backbone feature extraction network,is proposed based on an original Deeplabv3+deep learning model to address the issue of limited ***,through integrating the concept of pre-trained weights from transfer learning and implementing a freeze training strategy,signiﬁcant improvements have been made to enhance both the training speed and model training accuracy of this deep learning ***,based on segmented blade surface defect images,a method for quantifying blade defects is *** method combines image stitching algorithms to achieve overall quantiﬁcation and risk assessment of the entire *** results show that the improved Deeplabv3+deep learning model reduces training time by approximately 43.03%compared to the original model,while achieving mAP and MIoU values of 96.87%and 96.93%,***,it demonstrates robustness in detecting different surface defects on blades across different *** application of a blade surface defect quantiﬁcation method enables the precise quantiﬁcation of dif-ferent defects and facilitates the assessment of risk levels associated with defect measurements across the entire *** method enables non-contact,long-distance,high-precision detection and quantiﬁcation of surface defects on the blades,providing a reference for assessing surface defects on wind turbine blades.

关键词： Structural health monitoring computer vision blade surface defects detection Deeplabv3+ deep learning model

Removal of rubidium from brine by an integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide

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Chinese Journal of Chemical engineering 2024年第5期69卷 112-121页

作者： Huanxi Xu Peihua Lin Pei-Jun Liu Hai-Gang Liu Hui-Bin Guo Chao-Xiang Wu Ming Fang Xu Zhang Guan-Ping Jin Anhui Province engineering research center of Flexible and Intelligent Materials School of Chemistry and Chemical EngineeringHefei University of TechnologyHefei 230009China Chemical Design and research Institute Co. LTD of Qinghai ProvinceQinghai Engineering and Technology Research Center of Fine ChemicalXining 810008China

A novel integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide(KCuFC/SPSG)was used for selectively extracting rubidium ion(Rb^(+))from *** form KCuFC/SPSG,the precursor film of sulfonated polysulfone/graphene(SPSG)was synthesized by phase conversion process,which was alternately immersed in 0.1 mol·L^(-1)CuSO_(4)/K_(4)[Fe(CN)_(6)]by in-situ adsorption coupled co-precipitation *** data such as nuclear magnetic resonance spectrometer,Fourier transform infrared spectroscope,X-ray photoelectron spectroscope,X-ray diffraction,scanning electron microscope,and energy dispersive spectroscopy all verified that abundant KCuFC were uniformly located on the *** resulting KCuFC/SPSG was used in film separation *** the solution was fed into the system,the Rb^(+)could be selectively adsorption by KCuFC/*** the saturation adsorption,0.5 mol·L^(-1)NH_(4)Cl/HCl was fed into the film cell,Rb^(+)could be quickly desorbed by ion-exchange between Rb^(+)and NH_(4)^(+)in the lattice of *** purpose of separating and recovering Rb^(+)from the brine can be achieved after the repeated *** effects of pH,adsorption time,and interferential ions on the adsorption capacity of Rb^(+)were investigated by batch *** adsorption behavior fits the pseudo-second order kinetic process,while KCuFC has a higher adsorption capacity(Langmuir maximum sorption 165.4 mg·g^(-1)).In addition,KCuFC/SPSG shows excellent selectivity for Rb^(+)even in complex brine ***/SPSG could maintain 93.5%extraction efficiency after five adsorption/desorption cycles.

关键词： Rubidium extraction Potassium copper ferricyanide Sulfonated polysulfone Graphene oxide Adsorption

Global analysis of basic leucine zipper transcription factors in trifoliate orange and the function identification of PtbZIP49 in salt tolerance

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Horticultural Plant Journal 2024年第1期10卷 115-130页

作者： Yuanyuan Xu Qiuling Hui Meng Li Hongxian Peng Yizhong He Changpin Chun Liangzhi Peng Xingzheng Fu National Citrus engineering research center Citrus Research InstituteSouthwest UniversityChongqing 400712China

As one of the most widely distributed and highly conserved transcription factors in eukaryotes,basic leucine zipper proteins(bZIPs)are involved in a variety of biological processes in plants,but they are largely unknown in *** this study,56 bZIP family members were identified genome-wide from an important citrus rootstock,namely trifoliate orange(Poncirus trifoliata ***.),and these putative bZIPs were named PtbZIP1—*** PtbZIPs were classified into 13 subgroups by phylogenetic comparison with Arabidopsis thaliana bZIPs(AtbZIPs),and they were randomly distributed on nine known(50 genes)chromosomes and one unknown(6 genes)*** analysis revealed the detailed characteristics of PtPZIPs,including their amino acid length,isoelectric point(pI),molecular weight(MW),predicted subcellular localization,gene structure,and conserved *** of promoter elements suggested the presence of drought,low-temperature,wound,and defense and stress responsive elements,as well as multiple hormone-responsive cis-acting *** expression analysis showed the transcriptional patterns of PtbZIPs in different tissues and under dehydration,high salt,ABA,and IAA *** addition,21 PtbZIPs were predicted to have direct or indirect protein—protein *** these,PtbZIP49 was experimentally proven to interact with PtbZIP1 or PtbZIP11 by using a yeast two-hybrid assay and bimolecular fluorescence complementation(BiFC).Subcellular localization analysis further revealed that PtbZIP1,PtbZIP11,and PtbZIP49 were localized in the ***,PtbZIP49 was functionally identified as having an important role in salt stress via ectopic expression in *** and silenced in trifoliate orange using virus-induced gene silencing(VIGS).This study provided comprehensive information on PtbZIP transcription factors in citrus and highlights their potential functions in abiotic stress.

关键词： bZIP Citrus Trifoliate orange Abiotic stress Expression pattern

Comparative analysis between single-train passing and double-train intersection in a tunnel

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2024年第5期25卷 429-442页

作者： Jianming DU Qian FANG Xuan ZHANG Hualao WANG Bridge and Tunnel research center Research Institute of Highway Ministry of TransportBeijing 100088China Tunnel and Underground engineering research center of Ministry of Education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service *** aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single *** used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track ***,the numerical method was verified by comparing the results of numerical simulation and on-site ***,the characteristics of aerodynamic pressure were ***,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was *** results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel *** addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel *** pressure amplitude in the two-train case is higher than that for a single *** maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage *** P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage *** P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

Tuning mechanical and electrical performances of B_(4)C-TiB_(2)ceramics in a two-step spark plasma sintering process

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Journal of Advanced Ceramics 2024年第4期13卷 518-528页

作者： Jun Zhao Xingshuo Zhang Zongning Ma Dong Wang Xing Jin Songlin Ran Advanced Ceramics research center School of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243002China Anhui engineering research center for High Efficiency Intelligent Photovoltaic Module Chaohu UniversityHefei 238024China

B_(4)C–TiB_(2)is an advanced electrically conductive ceramic with excellent mechanical and electrical discharge machinable *** is challenging and rewarding to achieve highly conductive and hard B_(4)C–TiB_(2)composites at a minimum content of conductive TiB2 that has inferior hardness but double specific gravity of the B_(4)C matrix.A novel strategy was used to construct conductive networks in B_(4)C‒15 vol%TiB2 composite ceramics with B_(4)C,TiC,and amorphous B as raw materials by a two-step spark plasma sintering *** influences of particle size matching between B_(4)C and TiC on the conducting of the strategy and the microstructure were discussed based on the selective matrix grain growth *** mechanical and electrical properties were also systematically *** B_(4)C–15 vol%TiB2 composite ceramic prepared from 10.29µm B_(4)C and 0.05µm TiC powders exhibited a perfect three-dimensional interconnected conductive network with a maximum electrical conductivity of 4.25×10^(4)S/m,together with excellent mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 691±58 MPa,30.30±0.61 GPa,and 5.75±0.32 MPa·m^(1/2),respectively,while the composite obtained from 3.12µm B_(4)C and 0.8µm TiC powders had the best mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 827±35 MPa,32.01±0.51 GPa,and 6.45±0.22 MPa·m^(1/2),together with a decent electrical conductivity of 0.65×10^(4)S/m.

关键词： B_(4)C-TiB_(2) mechanical properties electrical conductivity conductive network

Identifying drivers of urban landuse changes in the Wenchuan earthquake- affected area by using night-time light data

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Journal of Mountain Science 2024年第4期21卷 1140-1159页

作者： HUANG Tao DING Mingtao GENG Dongxian GAO Zemin ZHENG Hao School of Civil engineering and Architecture Southwest University of Science and TechnologyMianyang 621010China Faculty of Geosciences and Environmental engineering Southwest Jiaotong UniversityChengdu 611756China Analysis and test center of Sichuan Province Chengdu 610023China

To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken ***,spatiotemporal evolution and its driving factors of urban land in earthquake-prone areas remains limited due to the scarcity of ground observation *** research,leveraging night-time light remote sensing imagery and land cover data,conducted a comprehensive analysis of the long-term evolution characteristics of urban land in earthquake-prone *** introduced methodologies for assessing the socio-economic impact and the primary natural environmental factors driving urban land evolution in these *** validate the proposed methods,the 2008 Wenchuan earthquake-affected area in China was selected as a representative study *** results indicated that the average Digital Number(DN)values in socio-economically impacted areas showed a trend of rising,falling,and then rising again after the *** values in three types of damaged areas including Type Ⅱ,Type Ⅲ,and Type Ⅳ exceeded pre-earthquake *** analysis of determinative factors influencing urban land evolution revealed that slope and elevation were key elements in controlling urban land expansion before the earthquake,whereas factors such as slope,elevation,lithology,and faults had a stronger influence on urban land expansion after the *** can be seen that,in view of the differences in the natural conditions of regions for post-disaster reconstruction,the local government need to actively adjust and adapt to urban spatial planning,so as to leverage the scale effect of large-scale inputs of funds,facilities,human resources and other factors after the disaster,thus enhancing resilience and recovery efficiency in response to disaster impacts.

关键词： Wenchuan earthquake Night-time lights Urban land Post-earthquake reconstruction

How Does Stacking Pressure Affect the Performance of Solid Electrolytes and All-Solid-State Lithium Metal Batteries?

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Energy & Environmental Materials 2024年第4期7卷 93-98页

作者： Junwu Sang Bin Tang Yong Qiu Yongzheng Fang Kecheng Pan Zhen Zhou Interdisciplinary research center for Sustainable Energy Science and engineering (IRC4SE2) School of Chemical Engineering Zhengzhou University

All-solid-state lithium metal batteries (ASSLMBs) with solid electrolytes (SEs)have emerged as a promising alternative to liquid electrolyte-based Li-ion batteries due to their higher energy density and ***,since ASSLMBs lack the wetting properties of liquid electrolytes,they require stacking pressure to prevent contact loss between electrodes and SEs.

关键词： critical current density solid electrolyte solid-state lithium metal batteries stacking pressure

Observation of an upward lightning flash with 21 upward positive leaders initiated from different wind turbines in wind farm

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High Voltage 2024年第1期9卷 163-171页

作者： Li Cai Yifeng Ke Wenchao Fan Ruisheng Yan Mi Zhou Jianguo Wang Yadong Fan engineering research center of Ministry of Education for Lightning Protection and Grounding Technology School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

As the wind turbine height increases,the probability of multiple upward leaders flashes within the wind farm *** this study,an upward lightning flash containing 21 upward positive leaders(UPLs)initiated from different wind turbines in Zhangbei Wind Farm was *** average speed of the UPLs was 1.2×10^(5) m/s,which mostly decreased to zero before reaching the cloud *** four UPLs developed to cloud height,with prolonged periods of bright light on three of them and with a minimum duration of 126 ms.A total of nine return strokes occurred on the other two dissipated leader channels,and the numbers of strokes on the two channels was six and three,*** average interstroke interval for the return strokes was 10.5 *** of these nine return strokes had peak currents smaller than 10 *** high-speed video frames confirmed that competition does exist between the UPLs,and the range of shielding effects increases as the height of the ULs *** effect of fan rotation on the initiation of upward leaders and the shielding effect between the wind turbines and upward leaders are discussed.

关键词： flash return initiated