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Journal of Advanced Ceramics 2024年第7期13卷 976-986页

作者： Lin Dong Wen-Qi Yang Lin Chen Guan-Jun Yang Chang-Jiu Li State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China xi’an Aerospace Engine company Limited in China Aerospace science and technology Corporation Xi’an 710065China

The lifetime of Si-based environmental barrier coatings(EBCs)is constrained by thermally grown SiO_(2)oxidelayer(SiO_(2)-TGO),which can cause premature cracking and *** address this issue,a new approach for surfacemodification using aluminum is *** oxidation performance was examined in a 50 vol%H_(2)O-50 vol%O_(2)environment at 1350℃for up to 300 *** results indicate that a dense ytterbium aluminum garnet(YbAG)layer wasformed after modification,decreasing the porosity by 80%.Due to the elimination of fast diffusion channels and the lowoxygen permeability of YbAG,aluminum modification significantly reduced the growth rate of SiO_(2)-TGO by nearly twoorders of ***,its thickness decreased by more than 70%after 300 h of exposure.A diffusioncontrolled oxidation mechanism indicates that the modified dense surface is equivalent to an initial SiO_(2)layer with a specificthickness,causing a shift in the oxidation time and increasing the oxidation *** research provides valuableinsights for designing Si-based EBC with improved lifetimes.

关键词： environmental barrier coating(EBC) oxidation modification diffusion cracking

Constraints of palaeoenvironment on organic matter of Benxi Formation shale and discussion on enrichment mechanism under different facies

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Frontiers of Earth science 2024年第1期18卷 148-171页

作者： Qianyang HE Delu LI Qiang SUN Jianwen GAO Haibin LI xinhu LI xiaochen ZHAO Shaofei WANG Gaozhe JI College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation Xi’an University of Science and TechnologyXi’an 710054China Geological Research Institute for Coal Green Mining Xi’an University of Science and TechnologyXi’an 710054China Research Institute of Exploration and development PetroChina Changqing Oilfield CompanyXi’an 710018China School of Civil Engineering and Architecture Shaanxi University of TechnologyHanzhong 723001China

As a hydrocarbon-rich sedimentary basin in China,the Ordos Basin has enormous potential for shale gas *** shale of the Upper Carboniferous Benxi Formation is rich in organic matter,however,its palaeoenvironment and organic matter enrichment mode are yet to be *** this study,the geochemical characteristics of the shale of the Benxi Formation in the east-central part of the Ordos Basin were analyzed to investigate its *** the same time,the organic matter enrichment modes in different sedimentary facies were compared and *** results indicate that:1)the shale of the Benxi Formation was mainly deposited on the continental margin and strong terrestrial clastic input;2)the deposition period of the Benxi Formation shale had a hot and humid climate with high palaeoproductivity and local volcanic hydrothermal fluid,and a high sedimentation rate with the strong stagnant *** bottom water was in dysoxic conditions and a semi-saline deposition environment;3)multiple factors,such as palaeoproductivity,volcanic hydrothermal,redox conditions,and palaeosalinity interact to influence the enrichment of shale organic matter in Benxi Formation;4)the organic matter enrichment modes of continental,marine-continental transitional,and marine shales can be classified into three types:“production mode”,“hybrid mode of preservation and production”,and“preservation mode”,*** study provides a reference for the organic matter enrichment mode,shale gas formation conditions,and core area evaluation in these marine-continental transitional shales,and also offers new guidance for exploration ideas for shale gas in different sedimentary facies.

关键词： Benxi Formation shale palaeoenvironment organic matter enrichment facies

Research on the mechanism of rockburst induced by mined coal-rock linkage of sharply inclined coal seams

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 929-942页

作者： xingping Lai Huicong Xu Pengfei Shan Qinxin Hu Weixi Ding Shangtong Yang Zhongming Yan College of Energy science and Engineering Xi’an University of Science and TechnologyXi’an 710054China State Key Laboratory of Green Low Carbon development of Oil-rich Coal in Western China Xi’an 710054China College of Future technology Xi’an University of Science and TechnologyXi’an 710054China Department of Civil and Environmental Engineering University of StrathclydeGlasgowG11XJUK

In recent years,the mining depth of steeply inclined coal seams in the Urumqi mining area has gradually *** deformation of mining coal-rock results in frequent *** has become a critical issue that affects the safe mining of deep,steeply inclined coal *** this work,we adopt a perspective centered on localized deformation in coal-rock mining and systematically combine theoretical analyses and extensive data mining of voluminous microseismic *** describe a mechanical model for the urgently inclined mining of both the sandwiched rock pillar and the roof,explaining the mechanical response behavior of key disaster-prone zones within the deep working face,affected by the dynamics of deep *** exploring the spatial correlation inherent in extensive microseismic data,we delineate the“time-space”response relationship that governs the dynamic failure of coal-rock during the progression of the sharply inclined working *** results disclose that(1)the distinctive coal-rock occurrence structure characterized by a“sandwiched rock pillar-B6 roof”constitutes the origin of rockburst in the southern mining area of the Wudong Coal Mine,with both elements presenting different degrees of deformation localization with increasing mining depth.(2)As mining depth increases,the bending deformation and energy accumulation within the rock pillar and roof show nonlinear *** localized deformation of deep,steeply inclined coal-rock engenders the spatial superposition of squeezing and prying effects in both the strike and dip directions,increasing the energy distribution disparity and stress asymmetry of the“sandwiched rock pillar-B3+6 coal seam-B6 roof”*** makes worse the propensity for frequent dynamic disasters in the working face.(3)The developed high-energy distortion zone“inner-outer”control technology effectively reduces high stress concentration and energy distortion in the surrounding *** implementation,the averag

关键词： steeply inclined coal seam localized deformation mechanism of induced rockburst prevention and control of rockburst

Stress Concentration Effect in Interface Between Conductor and Epoxy Resin in Coaxial Components of Power Equipment

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 412-420页

作者： Chuang Wang Kang Lei Qing Sun Hui Li Jiawei Zhang Lang Zhao Zongren Peng School of Electrical Engineering Xi’an University of TechnologyXi’an 710054China xi’an Power Supply company State Grid Shaanxi Electric Power CompanyXi’an 710032China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an 710049China

The spacer used in gas insulated switchgear(GIS)plays a vital role in its safe *** mismatch of mechanical properties between conductor and insulating material in spacers results in stress concentration at the interface between *** a hydrostatic test,mechanical damages are often initiated from the *** this paper,the stress between aluminum conductors and epoxy resin is studied by using a simplified coaxial structure *** measurement system and finite element simulation are used to explore the generation of stress and strain during curing and *** real-time measurement of strain at the interface shows that the residual strain in the entire process is primarily generated during the cooling ***,the temperature and stress/strain distribution at the interface during the cooling stage are further studied,and combined with experiments and *** consistency between the finite element simulation and the experimental measurement results verifies the validity of the simulation method *** results show that the maximum of the first principal stress generated during the cooling stage of the production process is concentrated on the upper and lower edges of the interface which is critical to the impact of the production quality of the spacer.

关键词： Epoxy resin GIS interface stress/strain distribution

Gates joint locally connected network for accurate and robust reconstruction in optical molecular tomography

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Journal of Innovative Optical Health sciences 2024年第3期17卷 11-22页

作者： Minghua Zhao Yahui xiao Jiaqi Zhang xin Cao Lin Wang School of Computer science and Engineering Xi’an University of TechnologyXi’anChina School of Information science and technology Northwest UniversityXi’an 710127China

Optical molecular tomography(OMT)is a potential pre-clinical molecular imaging technique with applications in a variety of biomedical areas,which can provide non-invasive quantitative three-dimensional(3D)information regarding tumor distribution in living *** construction of optical transmission models and the application of reconstruction algorithms in traditional model-based reconstruction processes have affected the reconstruction results,resulting in problems such as low accuracy,poor robustness,and long-time ***,a gates joint locally connected network(GLCN)method is proposed by establishing the mapping relationship between the inside source distribution and the photon density on surface directly,thus avoiding the extra time consumption caused by iteration and the reconstruction errors caused by model ***,gates module was composed of the concatenation and multiplication operators of three different *** was embedded into the network aiming at remembering input surface photon density over a period and allowing the network to capture neurons connected to the true source selectively by controlling three different *** evaluate the performance of the proposed method,numerical simulations were conducted,whose results demonstrated good performance in terms of reconstruction positioning accuracy and robustness.

关键词： Optical molecular tomography gates module positioning accuracy robustness

Social Robot Detection Method with Improved Graph Neural Networks

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Computers, Materials & Continua 2024年第2期78卷 1773-1795页

作者： Zhenhua Yu Liangxue Bai Ou Ye Xuya Cong Institute of Systems Security and Control College of Computer Science and TechnologyXi’an University of Science and TechnologyXi’an710054China

Social robot accounts controlled by artificial intelligence or humans are active in social networks,bringing negative impacts to network security and social *** social robot detection methods based on graph neural networks suffer from the problem of many social network nodes and complex relationships,which makes it difficult to accurately describe the difference between the topological relations of nodes,resulting in low detection accuracy of social *** paper proposes a social robot detection method with the use of an improved neural ***,social relationship subgraphs are constructed by leveraging the user’s social network to disentangle intricate social relationships ***,a linear modulated graph attention residual network model is devised to extract the node and network topology features of the social relation subgraph,thereby generating comprehensive social relation subgraph features,and the feature-wise linear modulation module of the model can better learn the differences between the ***,user text content and behavioral gene sequences are extracted to construct social behavioral features combined with the social relationship subgraph ***,social robots can be more accurately identified by combining user behavioral and relationship *** carrying out experimental studies based on the publicly available datasets TwiBot-20 and Cresci-15,the suggested method’s detection accuracies can achieve 86.73%and 97.86%,*** with the existing mainstream approaches,the accuracy of the proposed method is 2.2%and 1.35%higher on the two *** results show that the method proposed in this paper can effectively detect social robots and maintain a healthy ecological environment of social networks.

关键词： Social robot detection social relationship subgraph graph attention network feature linear modulation behavioral gene sequences

Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China

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Chinese Geographical science 2024年第2期34卷 342-356页

作者： SHI xiaoliang CHEN Jiajun DING Hao YANG Yuanqi ZHANG Yan College of Geomatics Xi’an University of Science and TechnologyXi’an 710054China

Precise and timely prediction of crop yields is crucial for food security and the development of agricultural ***,crop yield is influenced by multiple factors within complex growth *** research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter ***,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly *** study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat *** the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was *** estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)***,the determined optimal yield estimation method was used to predict winter wheat yield in three typical *** are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other *** best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe *** with severe drought year(201

关键词： winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time Henan Province,China

QAAS:quick accurate auto-scaling for streaming processing

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Frontiers of Computer science 2024年第1期18卷 5-15页

作者： Shiyuan LIU Yunchun LI Hailong YANG Ming DUN Chen CHEN Huaitao ZHANG Wei LI State Key Laboratory of Software development Environment Beijing 100191China School of Computer science and Engineering Beihang UniversityBeijing 100191China School of Cyber science and technology Beihang UniversityBeijing 100191China School of Computer science and technology Xi’an Jiaotong UniversityXi’an 710049China

In recent years,the demand for real-time data processing has been increasing,and various stream processing systems have *** the amount of data input to the stream processing system fluctuates,the computing resources required by the stream processing job will also *** resources used by stream processing jobs need to be adjusted according to load changes,avoiding the waste of computing *** present,existing works adjust stream processing jobs based on the assumption that there is a linear relationship between the operator parallelism and operator resource consumption(e.g.,throughput),which makes a significant deviation when the operator parallelism *** paper proposes a nonlinear model to represent operator *** divide the operator performance into three stages,the Non-competition stage,the Non-full competition stage,and the Full competition *** our proposed performance model,given the parallelism of the operator,we can accurately predict the CPU utilization and operator *** with actual experiments,the prediction error of our model is below 5%.We also propose a quick accurate auto-scaling(QAAS)method that uses the operator performance model to implement the auto-scaling of the operator parallelism of the Flink *** to previous work,QAAS is able to maintain stable job performance under load changes,minimizing the number of job adjustments and reducing data backlogs by 50%.

关键词： stream processing performance model auto-scaling

Diagnosing ratio of electron density to collision frequency of plasma surrounding scaled model in a shock tube using low-frequency alternating magnetic field phase shift

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Chinese Physics B 2024年第5期33卷 519-530页

作者：吴明兴谢楷刘艳徐晗张宝田得阳 School of Aerospace science and technology Xidian UniversityXi'an 710071China Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China

A non-contact low-frequency(LF)method of diagnosing the plasma surrounding a scaled model in a shock tube is *** method utilizes the phase shift occurring after the transmission of an LF alternating magnetic field through the plasma to directly measure the ratio of the plasma loop average electron density to collision *** equivalent circuit model is used to analyze the relationship of the phase shift of the magnetic field component of LF electromagnetic waves with the plasma electron density and collision *** applicable range of the LF method on a given plasma scale is *** upper diagnostic limit for the ratio of the electron density(unit:m^(-3))to collision frequency(unit:Hz)exceeds 1×10^(11),enabling an electron density to exceed 1×10^(20)m^(-3)and a collision frequency to be less than 1 *** this work,the feasibility of using the LF phase shift to implement the plasma diagnosis is also *** experiments on shock tube equipment are conducted by using both the electrostatic probe method and LF *** comparing the diagnostic results of the two methods,the inversion results are relatively consistent with each other,thereby preliminarily verifying the feasibility of the LF *** ratio of the electron density to the collision frequency has a relatively uniform distribution during the plasma *** LF diagnostic path is a loop around the model,which is suitable for diagnosing the plasma that surrounds the ***,the causes of diagnostic discrepancy between the two methods are *** proposed method provides a new avenue for diagnosing high-density enveloping plasma.

关键词： low-frequency alternating magnetic field phase shift shock-tube plasma diagnosis electron density collision frequency

Research progress of slippage characteristic and gas film stability enhancement methods on biomimetic hydrophobic surfaces

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Journal of Hydrodynamics 2024年第1期36卷 87-101页

作者： Meng-zhuo Zhang Hai-bao Hu Liu-zhen Ren Lu-yao Bao Jun Wen Luo xie School of Marine science and technology Northwestern Polytechnical UniversityXi’an710072China Research and development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China

The biomimetic hydrophobic surface is a potentially efficient underwater drag reduction method and the drag reduction mechanism of this kind of surface comes from the interfacial *** now,it is a hotspot to grasp the slippage characteristic and explore slippage enhancement *** paper not only summarizes our numerical simulation and experimental results of slippage characteristic at the solid-liquid interface(SLI)of hydrophobic surfaces(HS)and the gas-liquid interface(GLI)of superhydrophobic surfaces(SHS)in recent years,but also introduces some innovative methods that can effectively improve the gas film stability and drag reduction effect of ***,we used the molecular dynamics(MD)simulation method to figure out the effect of the solid-liquid interaction strength,the system temperature and the shear rate on the slippage of SLI,and expound their action mechanism from molecular ***,by MD and multibody dissipative particle dynamics(MDPD)method,the slippage behavior at the GLI was studied under the influence of the microstructure size and the flow driving *** proposed a new kind of hybrid slip boundary condition model to describe the slippage characteristic on *** addition,we found through experiment that a three-dimensional backflow will appear on the GLI under the interfacial adsorption of surfactants,and the backflow direction will reverse with the change of GLI ***,we put forward the wettability step structure and gas injection method to enhance the stability and drag reduction effect of the gas film on SHS.

关键词： Hydrophobic surface superhydrophobic surface interfacial slip underwater drag reduction