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Stability analysis of intermittently jointed rock slopes based on the stepped failure mode

Journal of Mountain Science 2024年第3期21卷 1019-1035页

作者： li Dejian FU Junwen li Hekai CHENG Xiao ZHAO lianheng ZHANG yingbin PENG Xinyan School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Institute for Disaster Management and Reconstruction College of Architecture&EnvironmentSichuan UniversityChengdu 610065China School of Civil Engineering Key Laboratory of Heavy-Haul Railway Engineering StructureMinistry of EducationHunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering StructureCentral South UniversityChangsha 410075China

In practical engineering,due to the noncontinuity characteristics of joints in rock slopes,in addition to plane failure,stepped sliding failure may occur for intermittently jointed rock *** for intermittently bedding jointed rock slopes,the correlation and difference in strength parameters between joints and rock bridges,along with the various failure modes and intermittency of rock bridges,contribute to the complexity of stepped failure modes and the unpredictability of failure *** on the upper-bound limit analysis method and multi-sliders step-path failure mode,considering the shear and tensile failure of rock bridges and the weakened relationship between the strength parameters of rock bridges and jointed surfaces,by introducing the modified M-C failure criterion and the formula for calculating the energy consumption of tensile failure of rock bridges,two failure mechanisms are constructed to obtain the safety factor(F_(s))of intermittently jointed rock *** sequential quadratic programming method is used to obtain the optimal upper-bound solution for F_(s).The influence of multiple key parameters(slope height H,horizontal distance L,Slope angleβ,shear strength parameters of the rock bridgeφr and cr,Dimensionless parameter u,weakening coefficients of the internal friction angle and cohesion between the rock bridges and joint surfaces Kφand Kc)on the stability analysis of intermittently jointed rock slopes under the shear failure mode of rock bridges as well as under the tensile failure mode is also *** reliability of the failure mechanisms is verified by comparative analysis with theoretical results,numerical results,and landslide cases,and the variation rules of F_(s)with each key parameter are *** results show that F_(s) varies linearly withφr and cr of the rock bridge and with K_(φ)and K_(c),whereas F_(s)changes nonlinearly with H and *** particular,with the increase in Kφand Kc,Fs increases by approximately 52.

关键词： Jointed rock slopes Stepped sliding failure Weakening characteristics Modified M‒C failure criterion

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MSC-YOLO:Improved YOLOv7 Based on Multi-Scale Spatial Context for Small Object Detection in UAV-View

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Computers, Materials & Continua 2024年第4期79卷 983-1003页

作者： Xiangyan Tang Chengchun ruan Xiulai li Binbin li Cebin Fu School of Computer Science and Technology Hainan UniversityHaikou570228China Hainan Blockchain Technology Engineering Research Center Hainan UniversityHaikou570228China School of Cyberspace Security(School of Cryptology) Hainan UniversityHaikou570228China

Accurately identifying small objects in high-resolution aerial images presents a complex and crucial task in thefield of small object detection on unmanned aerial vehicles(UAVs).This task is challenging due to variations inUAV flight altitude,differences in object scales,as well as factors like flight speed and motion *** enhancethe detection efficacy of small targets in drone aerial imagery,we propose an enhanced You Only Look Onceversion 7(YOLOv7)algorithm based on multi-scale spatial *** build the MSC-YOLO model,whichincorporates an additional prediction head,denoted as P2,to improve adaptability for small *** replaceconventional downsampling with a Spatial-to-Depth Convolutional Combination(CSPDC)module to mitigatethe loss of intricate feature details related to small ***,we propose a Spatial Context Pyramidwith Multi-Scale Attention(SCPMA)module,which captures spatial and channel-dependent features of smalltargets acrossmultiple *** module enhances the perception of spatial contextual features and the utilizationof multiscale feature *** the Visdrone2023 and UAVDT datasets,MSC-YOLO achieves remarkableresults,outperforming the baseline method YOLOv7 by 3.0%in terms ofmean average precision(mAP).The MSCYOLOalgorithm proposed in this paper has demonstrated satisfactory performance in detecting small targets inUAV aerial photography,providing strong support for practical applications.

关键词： Small object detection YOLOv7 multi-scale attention spatial context

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Non-contact air-coupled transducers Lamb wave signal multipath effect and blind separation for different modes using PZT as receiver

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Chinese Journal of Aeronautics 2024年第10期37卷 424-434页

作者： Desheng WU Zhibo YANG Yu ruan Wenbo li lijuan YANG Xuefeng CHEN National Key Lab of Aerospace Power System and Plasma Technology Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China

Due to the complexity and faintness of the detection wave patterns obtained by aircoupled transducers,if it is possible to effectively separate the various modes and obtain nondispersive signals for more accurate detection and positioning,it will help to improve the accuracy and reliability of air-coupled ultrasonic Lamb wave detection,providing better technical support for the application and development of related *** of the increased complexity of aircoupled signals,there is no definite theoretical formula to describe the mode changes of aircoupled signals,so the method based on blind separation has unique *** address these challenges,the paper proposes a single-channel blind source separation(SCBSS)*** effectiveness of this method is evaluated through simulations and experiments,demonstrating favorable separation results and efficient computational *** work first conducts an in-depth analysis of the signal characteristics of air-coupled ultrasonic non-destructive testing,and simulates the ultrasonic excitation conditions of air-coupled sensors through finite element *** study of modal changes and multipath effects caused by the variation of the incidence angle of the ACT signal is carried out,and the situation of the Lamb wave signal excited by ACT at the receiving end is *** combining ACT with PZT signals,the ultrasonic signals of air-coupled Lamb waves are compared and studied,and their modal purification is carried out.

关键词： Air-coupled transducers Lamb wave Mode separation Blind source separation Non-destructive testing

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Colorectal cancer screening:The value of early detection and modern challenges

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World Journal of Gastroenterology 2024年第20期30卷 2726-2730页

作者： Jian li Zhi-Peng li Wen-Jie ruan Wei Wang department of Interventional Oncology Municipal Hospital Affiliated to Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina School of Medicine Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina

The screening of colorectal cancer(CRC)is pivotal for both the prevention and treatment of this disease,significantly improving early-stage tumor detection *** advancement not only boosts survival rates and quality of life for patients but also reduces the costs associated with ***,the adoption of CRC screening methods faces numerous challenges,including the technical limitations of both noninvasive and invasive methods in terms of sensitivity and ***,socioeconomic factors such as regional disparities,economic conditions,and varying levels of awareness affect screening *** coronavirus disease 2.19 pandemic further intensified these challenges,leading to reduced screening participation and increased waiting ***,the growing prevalence of early-onset CRC necessitates innovative screening *** response,research into new methodologies,including artificial intelligence-based systems,aims to improve the precision and accessibility of *** measures by governments and health organizations to enhance CRC screening efforts are underway,including increased advocacy,improved service delivery,and international *** role of technological innovation and global health collaboration in advancing CRC screening is *** such as artificial intelligence and gene sequencing are set to revolutionize CRC screening,making a significant impact on the fight against this *** the rise in early-onset CRC,it is crucial for screening strategies to continually evolve,ensuring their effectiveness and applicability.

关键词： Colorectal cancer Early detection Economic implications Noninvasive tests Quality of life Survival rates Therapeutic modalities Technical challenges

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Cone-beam computed tomography noise reduction method based on U-Net with convolutional block attention module in proton therapy

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Nuclear Science and Techniques 2024年第7期35卷 89-100页

作者： Xing-Yue ruan Xiu-Fang li Meng-Ya Guo Mei Chen Ming Lv Rui li Zhi-ling Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai201800China University of Chinese Academy of Sciences Beijing100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China department of Radiation Oncology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai Key Laboratory of Proton therapy Shanghai201801China

Cone-beam computed tomography(CBCT) is mostly used for position verification during the treatment process. However,severe image artifacts in CBCT hinder its direct use in dose calculation and adaptive radiation therapy re-planning for proton therapy. In this study, an improved U-Net neural network named CBAM-U-Net was proposed for CBCT noise reduction in proton therapy, which is a CBCT denoised U-Net network with convolutional block attention modules. The datasets contained 20 groups of head and neck images. The CT images were registered to CBCT images as ground truth. The original CBCT denoised U-Net network, sCTU-Net, was trained for model performance comparison. The synthetic CT(SCT) images generated by CBAM-U-Net and the original sCTU-Net are called CBAM-SCT and U-Net-SCT images, respectively. The HU accuracies of the CT, CBCT, and SCT images were compared using four metrics: mean absolute error(MAE), root mean square error(RMSE), peak signal-to-noise ratio(PSNR), and structure similarity index measure(SSIM). The mean values of the MAE, RMSE, PSNR, and SSIM of CBAM-SCT images were 23.80 HU, 64.63 HU, 52.27 dB, and 0.9919, respectively,which were superior to those of the U-Net-SCT images. To evaluate dosimetric accuracy, the range accuracy was compared for a single-energy proton beam. The γ-index pass rates of a 4 cm × 4 cm scanned field and simple plan were calculated to compare the effects of the noise reduction capabilities of the original U-Net and CBAM-U-Net on the dose calculation results. CBAM-U-Net reduced noise more effectively than sCTU-Net, particularly in high-density tissues. We proposed a CBAM-U-Net model for CBCT noise reduction in proton therapy. Owing to the excellent noise reduction capabilities of CBAM-U-Net, the proposed model provided relatively explicit information regarding patient tissues. Moreover, it maybe be used in dose calculation and adaptive treatment planning in the future.

关键词： Proton therapy Cone-beam CT CBAM-U-Net γ-index

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Legumain-triggered aggregable gold nanoparticles for enhanced intratumoral retention

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Chinese Chemical Letters 2024年第7期35卷 388-393页

作者： Zhi li Wenpei li Shaoping Jiang Chuan Hu Yuanyu Huang Maxim Shevtsov Huile Gao Shaobo ruan Advanced Research Institute of Multidisciplinary Sciences School of Life ScienceBeijing Institute of TechnologyBeijing 100081China Key Laboratory of Drug Targeting and Drug Delivery System West China School of PharmacySichuan UniversityChengdu 610041China Institute of Cytology of Russian Academy of Sciences(RAS) St.Petersburg 194064Russia

Insufficient intratumoral retention of nanomedicines remains the major challenge for broad implementation in clinical ***,we proposed a legumain-triggered aggregable gold nanoparticle(GNP)delivery platform(GNPs-A&C).GNPs-A&C could form intratumoral or intracellular aggregates in response to the overexpressed *** aggregates with size increase not only could reduce back-flow from interstitial space to peripheral bloodstream but also could restrict the cellular exocytosis,leading to enhanced intratumoral *** vitro studies demonstrated that GNPs-A&C possessed an excellent legumain responsiveness and the increased size was closely relevant with legumain *** vivo studies demonstrated GNPs-A&C possessed slower clearance rate and much higher intratumoral retention within legumain-overexpressed tumor compared to non-aggregable NPs,regardless of intravenous or intratumoral *** importantly,this delivery platform significantly improved the chemotherapeutic effect of doxorubicin(DOX)towards subcutaneous xenograft C6 *** effectiveness of this stimulus-responsive aggregable delivery system provides a thinking for designing more intelligent size-tunable nanomedicine that can substantially improve intratumoral retention.

关键词： Legumain Size-tunable Enhanced retention Stimulus-responsive Nanomedicine

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A data-fusion-model method for state of health estimation of li-ion battery packs based on partial charging curve

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Green Energy and Intelligent Transportation 2024年第5期3卷 1-12页

作者： Xingzi Qiang Wenting liu Zhiqiang Lyu Haijun ruan Xiaoyu li School of Internet Anhui UniversityHefei230039China Institute for Clean Growth&Future Mobility Coventry UniversityUK School of Mechanical Engineering Hebei University of TechnologyTianjin300130China

The estimation of State of Health(SOH)for battery packs used in Electric Vehicles(EVs)is a complex task with significant importance,accompanied by several *** study introduces a data-fusion model approach to estimate the SOH of battery *** approach utilizes dual Gaussian Process Regressions(GPRs)to construct a data-driven and non-parametric aging model based on charging-based Aging Features(AFs).To enhance the accuracy of the aging model,a noise model is established to replace the random ***,the statespace representation of the aging model is ***,the Particle Filter(PF)is introduced to track the unknown state in the aging model,thereby developing the data-fusion-model for SOH *** performance of the proposed method is validated through aging experiments conducted on battery *** simulation results demonstrate that the data-fusion model approach achieves accurate SOH estimation,with maximum errors less than 1.5%.Compared to conventional techniques such as GPR and Support Vector Regression(SVR),the proposed method exhibits higher estimation accuracy and robustness.

关键词： li-ion battery pack State of health Data-fusion-model method Particle filter Gaussian process regression Support vector regression

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Fabrication of UV-Curing linalool-Polysiloxane Hybrid Films with High Refractive Index and Transparency

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Journal of Renewable Materials 2024年第3期12卷 569-583页

作者： Wenqing Xiao Lewen Tan Xunjun Chen Qiaoguang li Yunqing ruan College of Chemistry and Chemical Engineering Zhongkai University of Agriculture and EngineeringGuangzhou510225China R&D department Guangzhou Silicon Core Material Technology Co.Ltd.Guangzhou510220China

In this article,a series of high refractive indices(1.50-1.53)thiol phenyl polysiloxane(TPS)were synthesized via hydrolytic sol-gel *** Fourier transform infrared spectra(FT-IR)and nuclear magnetic resonance spectra(NMR)results showed that TPS conformed to the predicted *** terpene linalool was exploited as photocrosslinker to fabricate UV-curing linalool-polysiloxane hybrid films(LPH)with TPS via photoinitiated thiol-ene *** rapidly cured under UV irradiation at the intensity of 80 mW/cm^(2) in 30 s,exhibiting good UV-curing *** optical transmittance of LPH in the wavelength of 300-800 nm was over 90%,exhibiting good optical *** water contact angle and water vapor permeability results showed that the introduction of phenyl groups enhance the hydrophobicity and water vapor barrier properties of *** results indicated the potential of LPHs in the applications of optical functional coatings.

关键词： UV-curing polysiloxane hybrid films high refractive index transparency

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Constructing a 3D multichannel structure to enhance performance of Ni–Co–Mn hydroxide electrodes for flexible supercapacitors

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Rare Metals 2024年第1期43卷 148-163页

作者： Zhi-Hui Xu Shi-Shuai Sun Xue-Lei li Zhi-Hui Zhang Hai-Ying li Shuang-Ting ruan Shou-Gen Yin Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Education)and Tianjin Key Laboratory for Photoelectric Materials and Devices School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China College of Science Tianjin University of TechnologyTianjin 300384China School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China

The balancing of the electrochemical performance,mechanical stability,and processing technology for applying supercapacitors to flexible and wearable electronics continues to encounter severe ***,we prepare Ni-Co-Mn hydroxide electrodes with a threedimensional multichannel structure via a simple hydrothermal *** are constructed using vertically contiguous nano sheets with a uniform thickness and rough *** electrodes can provide numerous electroactive sites and accelerate the transmission of electrolyte *** relationship between the structure and electrochemical performances is verified by experiments and theoretical ***-dimensional(2D)planar and one-dimensional(1D)fiber electrodes are prepared using a flexible carbon cloth(CC)and carbon fiber(CF),respectively,as *** assembled quasi-solid-state flexible asymmetric supercapacitor(FASC)with a twodimensional sandwich structure using NiCoMn-OH/CC as the electrode achieves a remarkable energy density of73.8 Wh·kg^(-1)at a power density of 1.03 kW·kg^(-1).The quasi-solid-state FASC with a 1D linear structure using NiCoMn-OH/CF as the electrode also attains a high energy density(12.9 Wh·kg^(-1)at a power density of0.75 W·kg^(-1)).Moreover,the electrochemical performances of the NiCoMn/CC//AC/CC and NiCoMn/CF//AC/CF FASCs are not disturbed at different bending angles(0°,45°,90°,135°and 180°),This indicates the superior flexibility of the *** also assemble a self-powered energy-harvesting storage system by integrating FASCs and commercial solar cells to verify its *** displays sustainable development potential for energy storage.

关键词： Supercapacitors Flexible Ni–Co–Mn hydroxide 3D multichannel structure High performances

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Degree of shade tolerance shapes seasonality of chlorophyll, nitrogen and phosphorus levels of trees and herbs in a temperate deciduous forest

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Journal of Forestry Research 2024年第4期35卷 60-72页

作者： Jiajia Zeng Fan liu Yuan Zhu Jiayi li Ying ruan Xiankui Quan Chuankuan Wang Xingchang Wang Aulin College Northeast Forestry UniversityHarbin 150040People’s Republic of China Center for Ecological Research Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021People’s Republic of China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China

Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf ***,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly *** this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous *** role of shade tolerance in shaping the seasonal variation and vertical differentiation was *** the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance *** a:b ratios gradually decreased with increasing shade *** N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf *** the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade ***,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the *** variations in N:P ratios suggest changes in N or P *** findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.

关键词： Leaf traits Leaf nutrients Seasonal variations Chlorophyll Nitrogen Phosphorus Shade tolerance Canopy layers

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