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Three-dimensional numerical analysis of plant-soil hydraulic interactions on pore water pressure of vegetated slope under different rainfall patterns

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3696-3706页

作者： Haowen Guo Charles Wang Wai Ng qi Zhang Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina

Understanding the pore water pressure distribution in unsaturated soil is crucial in predicting shallow landslides triggered by rainfall,mainly when dealing with different temporal patterns of rainfall ***,the hydrological response of vegetated slopes,especially three-dimensional(3D)slopes covered with shrubs,under different rainfall patterns remains unclear and requires further *** address this issue,this study adopts a novel 3D numerical model for simulating hydraulic interactions between the root system of the shrub and the surrounding *** series of numerical parametric studies are conducted to investigate the influences of slope inclination,rainfall pattern and rainfall *** rainfall patterns(advanced,bimodal,delayed,and uniform)and two rainfall durations(4-h intense and 168-h mild rainfall)are considered to study the hydrological response of the *** computed results show that 17%higher transpiration-induced suction is found for a steeper slope,which remains even after a short,intense rainfall with a 100-year return *** extreme rainfalls with advanced(PA),bimodal(PB)and uniform(PU)rainfall patterns need to be considered for the short rainfall duration(4 h),while the delayed(PD)and uniform(PU)rainfall patterns are highly recommended for long rainfall durations(168 h).The presence of plants can improve slope stability markedly under extreme rainfall with a short duration(4 h).For the long duration(168 h),the benefit of the plant in preserving pore-water pressure(PWP)and slope stability may not be sufficient.

关键词： Root-soil interactions Rainfall patterns Slope stability Three-dimensional(3D)

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Patterns and mechanisms of belowground carbon responses to changes in precipitation

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Journal of Plant Ecology 2024年第2期17卷 1-17页

作者： Hongyang Chen qi Zhang Lingyan Zhou Xuhui Zhou School of Forestry Key Laboratory of Sustainable Forest Ecosystem Management-Ministry ofEducationNortheast Forestry UniversityHarbin 150040China Research Center Shanghai Botanical Garden/Shanghai Engineering Research Center of Sustainable Plant InnovationShanghai 200231China

It is well known that aboveground productivity usually increases with ***,how belowground carbon(C)processes respond to changes in precipitation remains elusive,although belowground net primary productivity(BNPP)represents more than one-half of NPP and soil stores the largest terrestrial C in the *** paper reviews the patterns of belowground C processes(BNPP and soil C)in response to changes in precipitation from transect studies,manipulative experiments,modeling and data integration and *** results suggest the possible existence of nonlinear patterns of BNPP and soil C in response to changes in precipitation,which is largely different from linear response for aboveground productivity.C allocation,root turnover time and species composition may be three key processes underlying mechanisms of the nonlinear responses to changes in precipitation for belowground C *** addition,microbial community structure and long-term ecosystem processes(*** assemblage,soil texture,aggregate stability)may also affect patterns of belowground C processes in response to changes in *** last,we discuss implications and future perspectives for potential nonlinear responses of belowground C processes to changes in precipitation.

关键词： belowground processes BNPP nonlinear precipitation soil C

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Prediction of the Pore-Pressure Built-Up and Temperature of Fire-Loaded Concrete with Pix2Pix

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Computers, Materials & Continua 2024年第5期79卷 2907-2922页

作者： Xueya Wang Yiming Zhang qi Liu Huanran Wang Mechanics and Materials Science Research Center Ningbo UniversityNingbo315211China Jinyun Institute Zhejiang Sci-Tech UniversityLishui321400China School of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou310018China School of Computer Science Nanjing University of Information Science and TechnologyNanjing210044China

Concrete subjected to fire loads is susceptible to explosive spalling, which can lead to the exposure of reinforcingsteel bars to the fire, substantially jeopardizing the structural safety and stability. The spalling of fire-loaded concreteis closely related to the evolution of pore pressure and temperature. Conventional analytical methods involve theresolution of complex, strongly coupled multifield equations, necessitating significant computational efforts. Torapidly and accurately obtain the distributions of pore-pressure and temperature, the Pix2Pix model is adoptedin this work, which is celebrated for its capabilities in image generation. The open-source dataset used hereinfeatures RGB images we generated using a sophisticated coupled model, while the grayscale images encapsulate the15 principal variables influencing spalling. After conducting a series of tests with different layers configurations,activation functions and loss functions, the Pix2Pix model suitable for assessing the spalling risk of fire-loadedconcrete has been meticulously designed and trained. The applicability and reliability of the Pix2Pix model inconcrete parameter prediction are verified by comparing its outcomes with those derived fromthe strong couplingTHC model. Notably, for the practical engineering applications, our findings indicate that utilizing monochromeimages as the initial target for analysis yields more dependable results. This work not only offers valuable insightsfor civil engineers specializing in concrete structures but also establishes a robust methodological approach forresearchers seeking to create similar predictive models.

关键词： Fire loaded concrete spalling risk pore pressure generative adversarial network(GAN) Pix2Pix

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Differences and identification on multi-time hydrocarbon generation of carboniferous-permian coaly source rocks in the Huanghua Depression,Bohai Bay Basin

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Petroleum Science 2024年第2期21卷 765-776页

作者： Jin-Jun Xu Xian-Gang Cheng Shu-Nan Peng Jun-Cai Jiang qi-Long Wu Da Lou Fu-qi Cheng La-Mei Lin National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShandongChina PetroChina Dagang Oilfield Company Tianjin300280China

Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon ***,the deposition and hydrocarbon evolution process of ancient coal-bearing strata is characterized by multiple geological times,leading to obvious distinctions in their hydrocarbon generation potential,geological processes,and production,which affect the evaluation and exploration of hydrocarbon resources derived from coaly source rocks *** study aimed to identify the differences on oil-generated parent macerals and the production of oil generated from different coaly source rocks and through different oil generation *** with the analysis of previous tectonic burial history and hydrocarbon generation history,high-temperature and high-pressure thermal simulation experiments,organic geochemistry,and organic petrology were performed on the Carboniferous-Permian(C-P)coaly source rocks in the Huanghua Depression,Bohai Bay *** oil-generated parent macerals of coal's secondary oil generation process(SOGP)were mainly hydrogen-rich collotelinite,collodetrinite,sporinite,and cutinite,while the oil-generated parent macerals of tertiary oil generation process(TOGP)were the remaining small amount of hydrogen-rich collotelinite,sporinite,and cutinite,as well as dispersed soluble organic matter and unexhausted residual *** with coal,the oil-generated parent macerals of coaly shale SOGP were mostly sporinite and *** part of hydrogen-poor vitrinite,lacking hydrocarbon-rich macerals,and macerals of the TOGP,in addition to some remaining cutinite and a small amount of crude oil and bitumen from SOGP contributed to the oil *** results indicated that the changes in oil yield had a good junction between SOGP and TOGP,both coal and coaly shale had higher SOGP aborted oil yield than TOGP starting yield,and coaly shale TOGP peak oil yield was low

关键词： Thermal simulation Multi-time oil generation processes Coaly source rock Carboniferous-permian Huanghua Depression

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BACNN: Multi-scale feature fusion-based bilinear attention convolutional neural network for wood NIR classification

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Journal of Forestry Research 2024年第4期35卷 202-214页

作者： Zihao Wan Hong Yang Jipan Xu Hongbo Mu Dawei qi College of Science Northeast Forestry UniversityHarbin 150040People’s Republic of China

Effective development and utilization of wood resources is *** modification research has become an integral dimension of wood science research,however,the similarities between modified wood and original wood render it challenging for accurate identification and classification using conventional image classification ***,the development of efficient and accurate wood classification techniques is *** paper presents a one-dimensional,convolutional neural network(i.e.,BACNN)that combines near-infrared spectroscopy and deep learning techniques to classify poplar,tung,and balsa woods,and PVA,nano-silica-sol and PVA-nano silica sol modified woods of *** results show that BACNN achieves an accuracy of 99.3%on the test set,higher than the 52.9%of the BP neural network and 98.7%of Support Vector Machine compared with traditional machine learning methods and deep learning based methods;it is also higher than the 97.6%of LeNet,98.7%of AlexNet and 99.1%of ***,the classification method proposed offers potential applications in wood classification,especially with homogeneous modified wood,and it also provides a basis for subsequent wood properties studies.

关键词： Wood classification Near infrared spectroscopy Bilinear network SE module Anti-noise algorithm

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Revealing the Structure-Property Difference of Natural Rubber Prepared by Different Methods: Protein and Gel Content are Key Factors

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Chinese Journal of Polymer Science 2024年第4期42卷 457-467页

作者： Shao-qi Huang Jun-qi Zhang Yong Zhu Ling-Min Kong Lu-Sheng Liao Fu-Quan Zhang Zheng-Tian Xie Jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China Hainan Provincial Key Laboratory of Natural Rubber Processing Agricultural Products Processing Research Institute of Chinese Academy of Tropical Agricultural SciencesZhanjiang524001China

Natural rubber (NR) is widely used in various fields including aerospace, military industry and transportation due to its superior elasticity and comprehensive mechanical properties. Nonetheless, the commercial NR prepared by different methods usually exhibits different mechanical properties, primarily due to variations in processing conditions during the conversion from latex to bulk rubber material. Consequently, this poses challenges in scientific research and industrial production of NR. In order to assess the properties of various commercially available NR and identify key structural and compositional components, this study systematically compares and analyzes four representative NR raw materials: air dried sheet (ADS), ribbed smoked sheets (RSS), constant viscidity NR (CV), and whole field latex rubber (WF). The investigation focuses on evaluating their static mechanical behavior, SIC behavior, wear resistance, and fatigue resistance. The findings indicate that protein and gel content exhibit a crucial influence on the NR properties. These constituents contribute to the formation of a high-crosslinking density region, generating a heterogeneous network structure within the rubber. This structure amplifies strains during deformation, leading to earlier and stronger strain-induced crystallization (SIC). Among the four commercial NR brands, RSS demonstrates superior overall mechanical and dynamic properties owing to its high protein and gel content. This study serves as a valuable reference for comprehending the differences in properties among various commercial NR, thereby offering guidance for the actual processing and selection of NR.

关键词： Natural rubber Processingmethod Protein Gel content Property

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Multi-party privacy-preserving decision tree training with a privileged party

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Science China(Information Sciences) 2024年第8期67卷 253-268页

作者： Yiwen TONG qi FENG Min LUO Debiao HE Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of Education School of Cyber Science and Engineering Wuhan University Shanghai Technology Innovation Centre of Distributed Privacy-Preserving Artificial Intelligence Matrix Elements Technologies Key Laboratory of Computing Power Network and Information Security Ministry of EducationShandong Computer Science Center Qilu University of Technology(Shandong Academy of Sciences)

Currently, a decision tree is the most commonly used data mining algorithm for classification tasks. While a significant number of studies have investigated privacy-preserving decision trees, the methods proposed in these studies often have shortcomings in terms of data privacy breach or efficiency. Additionally,these methods typically only apply to symmetric frameworks, which consist of two or more parties with equal privilege, and are not suitable for asymmetric scenarios where parties have unequal privilege. In this paper,we propose SecureCART, a three-party privacy-preserving decision tree training scheme with a privileged party. We adopt the existing pMPL framework and design novel secure interactive protocols for division,comparison, and asymmetric multiplication. Compared to similar schemes, our division protocol is 93.5–560.4× faster, with the communication overhead reduced by over 90%; further, our multiplication protocol is approximately 1.5× faster, with the communication overhead reduced by around 20%. Our comparison protocol based on function secret sharing maintains good performance when adapted to pMPL. Based on the proposed secure protocols, we implement SecureCART in C++ and analyze its performance using three real-world datasets in both LAN and WAN environments. he experimental results indicate that SecureCART is significantly faster than similar schemes proposed in past studies, and that the loss of accuracy while using SecureCART remains within an acceptable range.

关键词： privacy protection decision trees secure multi-party computation secret sharing privileged party

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Multi-objective optimization of a high speed on/off valve for dynamic performance improvement and volume minimization

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Chinese Journal of Aeronautics 2024年第10期37卷 435-444页

作者： qi ZHONG Junxian WANG Enguang XU Cheng YU Yanbiao LI College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310023China

Hydraulic circuits with high speed on/off valve(HSV)for servo control have become commonplace in ***,the individual valve that is not volume-optimized results in a large total size of hydraulic control system,diminishing the *** address this issue,the high-precision equivalent reluctance model of the HSV is established by employing an equivalent magnetic circuit,on which the dynamic characteristic of the HSV,as well as the effects of structural parameters on switching behaviour,are *** on this model,multi-objective optimization is adopted to design an HSV with faster dynamic performance and smaller volume,NSGA-II genetic algorithm is applied to obtain the Pareto front of the desired *** assess the impact before and after optimization,an HSV based on the optimized structure is manufactured and *** experimental results show that the optimized HSV reduces 47.1%of its solenoid volume while improving opening and closing dynamic performance by 14.8%and 43.0%respectively,increasing maximum switching frequency by 6.2%,and expanding flow linear control area by 6.7%.These results validate the optimized structure and indicate that the optimization method provided in the paper is beneficial for developing superior HSV.

关键词： High speed on/off valve Dynamic response Volume Multiobjective optimization NSGA-II genetic algorithm

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Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

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Science China Chemistry 2024年第6期67卷 2002-2008页

作者： qi Meng Tao qin Huanran Miao Ge Zhang qian Zhang Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological ***,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and *** with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-N bond forging through an S_(N)2-like displacement involving dynamic kinetic resolution(DKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-N bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

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Significantly improved near-field communication antennas based on novel Ho^(3+)and Co^(2+)ions co-doped Ni-Zn ferrites

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Journal of Advanced Ceramics 2024年第3期13卷 293-309页

作者： Pao Yang Zhiqing Liu Hongbin qi Xiuli Fu Zhijian Peng School of Science China University of GeosciencesBeijing 100083China School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China Kunshan GuoLi Electronic Technology Co. Ltd.Kunshan 215300China

In near-field communication(NFC)antennas,soft magnetic ferrites are usually applied as a substrate to reduce eddy current loss and increase magnetic field *** this purpose,the applied ferrites are required to have high permeability and saturation magnetization together with low magnetic loss and dielectric ***,for most soft magnetic ferrites,it is difficult to meet all the *** novel Ni-Zn ferrite ceramics co-doped by Ho^(3+)and Co^(2+)ions with chemical formula Ni_(0.5-x)Zn_(0.5)Ho_(0.02)Co_(x)Fe_(1.98)O_(4)(x=0-0.2)were designed and prepared to balance these needs on the basis of molten salt synthesis with metal nitrates as raw materials and potassium hydroxide(KOH)as the precipitation agent and molten salt *** the substitution of Ho^(3+),the saturation magnetization and initial permeability decrease,but with further doping of Co^(2+),the saturation magnetization gradually increases,while the initial permeability continues to *** x=0.1,the sample will have the lowest dielectric constant,magnetic and dielectric loss,as well as the highest Curie temperature(305℃).Moreover,the acquired Ni-Zn ferrites have been applied simulatively in NFC antennas,revealing that the device manufactured with the optimal Ni_(0.4)Zn_(0.5)Ho_(0.02)Co_(0.1)Fe_(1.98)O_(4)ferrite ceramics would have significantly improved performance at 13.56 MHz with low leakage and long transmit distance of magnetic ***,the Ni_(0.4)Zn_(0.5)Ho_(0.02)Co_(0.1)Fe_(1.98)O_(4)ferrite ceramics would be a good candidate for NFC antenna substrates.

关键词： electromagnetic properties co-doping microstrip antennas Ni-Zn ferrite

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