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Application of multi-algorithm ensemble methods in high-dimensional and small-sample data of geotechnical engineering:A case study of swelling pressure of expansive soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1896-1917页

作者： chao li Lei Wang Jie li Yang chen School of Urban Railway Transportation Shanghai University of Engineering ScienceShanghai201620China Discipline of Civil and Infrastructure Engineering RMIT UniversityMelbourne3001Australia School of Naval Architecture and Civil Engineering Shanghai Jiao Tong UniversityShanghai200240China

Geotechnical engineering data are usually small-sample and high-dimensional,which brings a lot of challenges in predictive *** paper uses a typical high-dimensional and small-sample swell pressure(P_(s))dataset to explore the possibility of using multi-algorithm hybrid ensemble and dimensionality reduction methods to mitigate the uncertainty of soil parameter *** on six machine learning(ML)algorithms,the base learner pool is constructed,and four ensemble methods,Stacking(SG),Blending(BG),Voting regression(VR),and Feature weight linear stacking(FWL),are used for the multi-algorithm ***,the importance of permutation is used for feature dimensionality reduction to mitigate the impact of weakly correlated variables on predictive *** results show that the proposed methods are superior to traditional prediction models and base ML models,where FWL is more suitable for modeling with small-sample datasets,and dimensionality reduction can simplify the data structure and reduce the adverse impact of the small-sample effect,which points the way to feature selection for predictive *** on the ensemble methods,the feature importance of the five primary factors affecting P_(s) is the maximum dry density(31.145%),clay fraction(15.876%),swell percent(15.289%),plasticity index(14%),and optimum moisture content(13.69%),the influence of input parameters on P_(s) is also investigated,in line with the findings of the existing literature.

关键词： Expansive soils Swelling pressure Machine learning(ML) Multi-algorithm ensemble Sensitivity analysis

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Highly selectiveα-C(sp^(3))-H arylation of alkenyl amides via nickel chain-walking catalysis

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Chinese Chemical Letters 2024年第7期35卷 271-275页

作者： Haoran Shi Jiaxin Wang Yuqin Zhu Hongyang li guodong Ju Lanlan Zhang chao Wang Tianjin Key Laboratory of Structure and Performance for functional Molecules College of ChemistryTianjin Normal UniversityTianjin 300387China

Herein,we report the migratory hydroarylation of unactivated alkenes with aryl iodides using native and weakly coordinating amide directors under mild *** coordination of the monodentate directing group and the ligand enable the highly regioselective migratory hydroarylation via a chain walking process to form the thermodynamically stable five-membered nickelacyle *** protocol provides a variety of valuableα-aryl-substituted alkylamine products,and exhibited good functional group *** modification of bioactive compounds such as fenofibrate and indomethacin further highlights the synthetic value of this protocol.

关键词： Alkenes Hydroarylation Chain-walking Regioselective Nickel catalysis

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Sec-Auditor:A Blockchain-Based Data Auditing Solution for Ensuring Integrity and Semantic Correctness

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Computers, Materials & Continua 2024年第8期80卷 2121-2137页

作者： guodong Han Hecheng li College of Computer Qinghai Normal UniversityXining810008China

Currently,there is a growing trend among users to store their data in the ***,the cloud is vulnerable to persistent data corruption risks arising from equipment failures and hacker ***,when users perform file operations,the semantic integrity of the data can be *** both data integrity and semantic correctness has become a critical issue that requires *** introduce a pioneering solution called Sec-Auditor,the first of its kind with the ability to verify data integrity and semantic correctness simultaneously,while maintaining a constant communication cost independent of the audited data ***-Auditor also supports public auditing,enabling anyone with access to public information to conduct data *** feature makes Sec-Auditor highly adaptable to open data environments,such as the *** Sec-Auditor,users are assigned specific rules that are utilized to verify the accuracy of data ***,users are given the flexibility to update their own rules as *** conduct in-depth analyses of the correctness and security of *** also compare several important security attributes with existing schemes,demonstrating the superior properties of *** results demonstrate that even for time-consuming file upload operations,our solution is more efficient than the comparison one.

关键词： Provable data possession public auditing cloud storage data integrity semantic correctness

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Applicability and improvement of different potential evapotranspiration models in different climate zones of China

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Ecological Processes 2024年第1期13卷 262-282页

作者： Zedong li Yiran li Xinxiao Yu guodong Jia Peng chen Pengfei Zheng Yusong Wang Bingbing Ding Key Laboratory of Soil & Water Conservation and Desertification Combating of Ministry of Education Beijing Forestry University College of Horticulture and Forestry Sciences Tarim University State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical Science Beijing Normal University

Background Accurate estimation of potential evapotranspiration(PET) is the key for studying land-air interaction hydrological processes. Several models are used to estimate the PET based on standardized meteorological data. Although combination-based models have the highest level performance estimation of PET, they require more meteorological data and may therefore be difficult to apply in areas lacking meteorological observation *** The results showed significant differences in the spatial trends of PET calculated by different models in China, the Doorenbots–Pruitts model revealed the highest PET(1902.6 mm), and the Kuzmin model revealed the lowest PET(349.6 mm), with the largest difference being 5.5 times. The Romanenko and the Rohwer models were the recommended temperature-based and aerodynamic-based models. On the other hand, the Abtew model was more suitable for arid and semi-arid regions, while the Priestley–Taylor model was more suitable for humid regions. Combination-based models revealed ideal calculation accuracies, among which the Penman–Monteith model was the best option for PET *** The accuracy range of Romanenko, Rohwer, Abten, Priestley Taylor, and Penman Monteith models improved in MPZ and TCZ is higher than that improved in TMZ and SMZ. This does not mean that the improved models have higher accuracy in MPZ and TCZ than in TMZ and SMZ. On the contrary, the original model performed poorly in MPZ and TCZ, so the improved accuracy was relatively large. The unimproved model was already more suitable in TMZ and SMZ, so the improved accuracy was relatively small. Therefore, regional calibration of the PET models can improve the accuracy and applicability of PET calculation, providing a reference for studying hydrological processes in different climatic zones.

关键词： Potential evapotranspiration Climatic zone Temperature-based model Aerodynamic-based model Radiation-based model Combination-based model Model calibration

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Analysis of the Influence of Geometrical Parameters on the Performance of a Proton Exchange Membrane fuel Cell

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Fluid Dynamics & Materials Processing 2024年第1期20卷 219-237页

作者： guodong Zhang Huifang Tao Da li Kewei chen Guoxiang li Shuzhan Bai Ke Sun School of Energy and Power Engineering Shandong UniversityJinan250061China Sinotruk Jinan Special Purpose Vehicle Co. Ltd.Jinan250117China

A suitable channel structure can lead to efficient gas distribution and significantly improve the power density of fuel *** this study,the influence of two channel design parameters is investigated,namely,the ratio of the channel width to the bipolar plate ridge width(i.e.,the channel ridge ratio)and the channel *** impact of these parameters is evaluated with respect to the flow pattern,the gas composition distribution,the temperature field and the fuel cell output *** results show that a decrease in the channel ridge ratio and an increase in the channel depth can effectively make the distributions of velocity,temperature and concentration more uniform in each channel and improve the output capability of the fuel *** increase in the channel ridge ratio and depth obviously reduces the flow resistance and improves the flow characteristics.

关键词： Hydrogen fuel cell bipolar plate flow channel multiphysics coupling

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Plasmonic quantum dots modulated nano-mineral toward photothermal reduction of CO_(2)coupled with biomass conversion

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Nano Research 2024年第6期17卷 5061-5072页

作者： Guangbiao Cao Haoran Xing Haoguan Gui chao Yao Yinjuan chen Yongsheng chen Xiazhang li National-local Joint Engineering Research Center of Biomass Refining and High-quality Utilization Changzhou UniversityChangzhou 213164China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332-0373USA

Simultaneous conversion of CO_(2)and biomass into value-added chemicals through solar-driven catalysis holds tremendous importance for fostering a sustainable circular ***,plasmonic Bi quantum dots were immobilized on phosphoric acid modified attapulgite(P-ATP)nanorod using an in-situ reduction-deposition method,and were employed for photocatalytic reduction of CO_(2)coupled with oxidation of biomass-derived benzyl *** revealed that Bi atoms successfully integrated into the basal structure of P-ATP,forming chemically coordinated Bi-O-Si bonds that served as efficient transportation channels for *** incorporation of high-density monodispersed Bi quantum dots induced a surface plasmon resonance(SPR)effect,expanding the light absorption range into the near-infrared *** a consequence,the photo-thermal transformation was significantly accelerated,leading to enhanced reaction ***,50%Bi/P-ATP nanocomposite exhibited the highest plasmon-mediated photocatalytic CH4 generation(115.7μmol·g^(−1)·h^(−1))and CO generation(44.9μmol·g^(−1)·h^(−1)),along with remarkable benzaldehyde generation rate of 79.5μmol·g^(−1)·h^(−1)in the photo-redox coupling system under solar light *** hydrogen protons released from the oxidation of benzyl alcohol facilitated the incorporation of more hydrogen protons into CO_(2)to form key CH_(3)O−*** work demonstrates the synergistic solar-driven valorization of CO_(2)and biomass using natural mineral based catalyst.

关键词： photothermal catalysis clay mineral plasmon CO_(2)reduction biomass conversion

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Wireless semantic communication based on semantic matching multiple access and intent bias multiplexing

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 26-36页

作者： Ren chao He Zongrui Sun chen li Haojin Zhang Haijun University of Science and Technology Beijing Beijing 100083China Research and Development Center Sony(China)LimitedBeijing 100027China

This paper proposes a multi-access and multi-user semantic communication scheme based on semantic matching and intent deviation to address the increasing demand for wireless users and *** scheme enables flexible management of long frames,allowing each unit of bandwidth to support a higher number of *** leveraging semantic classification,different users can independently access the network through the transmission of long concatenated sequences without modifying the existing wireless communication *** overcome the potential disadvantage of incomplete semantic database matching leading to semantic intent misunderstanding,the scheme proposes using intent deviation as an *** allows different receivers to interpret the same semantic information differently,enabling multiplexing where one piece of information can serve multiple users with distinct *** results show that at a bit error rate(BER)of 0.1,it is possible to reduce the transmission by approximately 20 semantic basic units.

关键词： semantic communication multiple access multiplexing multimodal communication

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Thermofluidic investigations of oil natural transformer:Closed-loop modelling and experimental validation

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High Voltage 2024年第1期9卷 230-240页

作者： Yuan li Yiran Gao chen Wang chao Zhu Ying li Yuankai Wang Guanjun Zhang State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina Electric Power Research Institute of State Grid Shaanxi Electric Power Co. Ltd.Xi'anChina TBEA Hengyang Transformer Co. Ltd.HengyangChina

Excessively high temperatures inside a power transformer can accelerate the ageing rate and even cause unplanned *** estimating the hot-spot temperature(HST)of a power transformer is important for regulating the load and ensuring long-term *** this study,a closed-loop model of a 110-kV product transformer with an oil natural/air forced(ONAF)cooling mode is built to predict HST,in which the compression ratio of windings,equivalent heat source and radiator geometry are *** to the flow field of the winding,the‘dead oil zone’and reverse oil flow are observed in the horizontal oil *** accuracy of the proposed model is experimentally validated by temperature-rise *** results show that the absolute errors between the measured results and simulation are below 5°C,and the average error is~2°***,the arrangements of windings and radiators are studied to enhance the oil *** adding 5 washers to the high-voltage winding,the average temperature can be decreased by 6°C compared with the case without a *** the radiator can also mitigate the characteristic temperatures,and the optimal height difference between the radiator and winding centre is suggested to be 0.66 m.

关键词： winding arrangement adding

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Universal and efficient hybrid modeling and direct slicing method for additive manufacturing processes

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Advances in Manufacturing 2024年第2期12卷 300-316页

作者： Sen-lin Wang li-chao Zhang chao Cai Ming-Kai Tang Si chen Jiang Huang Yu-Sheng Shi State Key Laboratory of Materials Processing and Die and Mould Technology Huazhong University of Science and TechnologyWuhan430074People’s Republic of China School of Machinery and Automation Wuhan University of Science and TechnologyWuhan430081People’s Republic of China

Model design and slicing contour generation in additive manufacturing(AM)data processing face challenges in terms of efficiency and scalability when stereolithography files generated by complex functionally graded structures have millions of *** paper proposes a hybrid modeling and direct slicing method for AM to efficiently construct and handle complex three-dimensional(3D)*** 3D solids,including conformal multigradient structures,were uniformly described using a small amount of data via signed distance *** hybrid representations were quickly discretized into numerous disordered directed lines using an improved marching squares *** establishing a directional HashMap to construct the topological relationship between lines,a connecting algorithm with linear time complexity is proposed to generate slicing contours for *** method replaces the mesh reconstruction and Boolean operation stages and can efficiently construct complex conformal gradient models of arbitrary topologies through hybrid ***,the time and memory consumption of direct slicing are much lower than those of previous methods when handling hybrid models with hundreds of millions of faces after mesh reconstruction.

关键词： Additive manufacturing(AM) Hybrid modeling Direct slicing Signed distance field

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Highly elastic and degradable vitrimeric elastomers using polycondensation

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Chinese Chemical Letters 2024年第3期35卷 434-438页

作者： Yue liu Yongshuang Huang chao li Guifu Si Min chen Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei 230601China CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Introducing covalently crosslinked network to polymer matrix can merge the advantages in reprocessing and durability of *** this contribution,a series of high-performance vitrimeric elastomers were achieved via *** topological structures of polymers were tuned by varying the feeding ratios of bisacetoacetate,hex–substituted bisacetoacetate,bisamine and tris(2-aminoethyl)*** these structural manipulations,the vitrimeric elastomers presented great elastic recovery properties(strain recovery value up to 80%)benefiting from the introduction of long chain ***,the elastomers exhibited excellent reprocessing property,water vapor/oxygen barrier and adhesive ***,the elastomers could be degraded into monomer under acid conditions which enabled the elastomer synthesis again in closed loop recycling *** ease of the polycondensation in this work to prepare highly elastic and recyclable vitrimeric elastomers demonstrated exciting opportunities for the synthesis of sustainable polymers.

关键词： Polycondensation Vitrimeric elastomers Highly elastic Degradable polymers

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