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Strong Edge Coloring of Outerplane Graphs with Independent Crossings

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 467-477页

作者： Ke-Jie li xin zhang school of Mathematics and Statistics Xidian UniversityXi’an 710071China

The strong chromatic index of a graph is the minimum number of colors needed in a proper edge coloring so that no edge is adjacent to two edges of the same *** outerplane graph with independent crossings is a graph embedded in the plane in such a way that all vertices are on the outer face and two pairs of crossing edges share no common end *** is proved that every outerplane graph with independent crossings and maximum degreeΔhas strong chromatic index at most 4Δ-6 if Δ≥4,and at most 8 ifΔ≤*** bounds are sharp.

关键词： outer-1-planar graph IC-planar graph strong edge coloring crossing

Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining

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china Ocean Engineering 2024年第1期38卷 42-53页

作者： liU Lei liU Jian-cheng li {3. XU li-{3. zhang Xiu-zhan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China school of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China china Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China china Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China school of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on *** hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial *** the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle *** hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow *** transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture *** qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were *** local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic *** effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport.

关键词： deepsea mining vertical hydraulic transport experiment flow characteristics

Aggregation of CeAlO_(3. inclusions in heavy ingot of a steel containing 0.007% aluminum

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Journal of Iron and Steel Research International 2024年第8期31卷 1960-1972页

作者： Qiu-yue Zhou Jun-tao Ba lun zhang Wei Chen Ying Ren li-feng zhang school of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China school of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina school of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The distribution of inclusions at the bottom of a Ce-treated heavy steel ingot was detected and *** three-dimensional morphology and spatial distribution of CeAlOs clusters were characterized using the electrolytic extraction and Micro-CT detection.A model of inclusion collision to predict the aggregation of CeAlO_(3. inclusions in the ingot was established and validated by measured *** were mainly CeAlO_(3. and a small amount of Ce_(2)O_(2)S in the tundish after cerium *** collision and aggregation of inclusions led to the formation of large clusters in the ingot during the solidification *** slag entrainment inclusions,large CeAO_(3. clusters and small CeAlO_(3. particles were observed from the center to the edge of the ingot *** inclusions were mainly concentrated at the *** number density of inclusions larger than 200μm was 0.21 mm^(-3..The maximum diameter of CeA1O_(3. clusters was 13.0μ*** the edge to the radial center and from the bottom to the top,the average diameter of inclusions gradually increased due to the longer solidification time of the ingot.

关键词： Inclusion Heavy ingot Cerium treatment Collision

Joint fuzzy background and adaptive foreground model for moving target detection

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Frontiers of Computer Science 2024年第2期18卷 93-106页

作者： Dawei zhang Peng WANG Yongfeng DONG linhao li {3. li school of Artificial Intelligence Hebei University of TechnologyTianjin 300401China Lane Department of Computer Science and Electrical Engineering West Virginia UniversityMorgantownWV 26506-6109USA

Moving target detection is one of the most basic tasks in computer *** conventional wisdom,the problem is solved by iterative optimization under either Matrix Decomposition(MD)or Matrix Factorization(MF)*** utilizes foreground information to facilitate background *** uses noise-based weights to fine-tune the *** both noise and foreground information contribute to the recovery of the *** jointly exploit their advantages,inspired by two framework complementary characteristics,we propose to simultaneously exploit the advantages of these two optimizing approaches in a unified framework called Joint Matrix Decomposition and Factorization(JMDF).To improve background extraction,a fuzzy factorization is *** fuzzy membership of the background/foreground association is calculated during the factorization process to distinguish their contributions of both to background *** describe the spatio-temporal continuity of foreground more accurately,we propose to incorporate the first order temporal difference into the group sparsity constraint *** temporal constraint is adjusted *** foreground and the background are jointly estimated through an effective alternate optimization process,and the noise can be modeled with the specific probability *** experimental results of vast real videos illustrate the effectiveness of our *** with the current state-of-the-art technology,our method can usually form the clearer background and extract the more accurate ***-noise experiments show the noise robustness of our method.

关键词： matrixdecomposition matrix factorization generalized sparsity noise modeling

Threshold Selection and Resource Allocation for Quantized Identification

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Journal of Systems Science & Complexity 2024年第1期37卷 204-229页

作者： WANG Ying li xin ZHAO Yanlong zhang Ji-Feng Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China school of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper is concerned with the optimal threshold selection and resource allocation problems of quantized identification, whose aims are improving identification efficiency under limited resources. Firstly, the first-order asymptotically optimal quantized identification theory is extended to the weak persistent excitation condition. Secondly, the characteristics of time and space complexities are established based on the Cramér-Rao lower bound of quantized systems. On these basis, the optimal selection methods of fixed thresholds and adaptive thresholds are established under aperiodic signals, which answer how to achieve the best efficiency of quantized identification under the same time and space complexity. In addition, based on the principle of maximizing the identification efficiency under a given resource, the optimal resource allocation methods of quantized identification are given for the cases of fixed thresholds and adaptive thresholds, respectively, which show how to balance time and space complexity to realize the best identification efficiency of quantized identification.

关键词： Quantized output resource allocation system identification threshold selection.

Micro-nanoarchitectonic of aluminum-hydrogel propellant with static stability and dynamic rheology

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 87-96页

作者： Huiyan Guo Huaiyu li Hongzhi zhang lun Pan Chengxiang Shi Kang Xue Xiangwen zhang Ji-Jun Zou Key Laboratory for Advanced Fuel and Propellant of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

The aluminum-water system is a promising propellant due to high energy and low signal characteristics,and the gel form is easier to store and *** this work,hydrogels of water and aluminum particles were prepared using the low-molecular-weight gellant *** various physical properties of gel systems,including the water loss rate,phase transition temperature,and centrifugal stability at different gellant and aluminum contents,were *** properties were assessed through shear thinning tests,thixotropy tests,strain sweep analysis,and frequency sweep *** microstructure of the gel was obtained through scanning electron microscopy *** results show that the aluminum-hydrogel network structure is composed of micron-scale aluminum and agarose nanosheets,and the unique micro-nanostructure endows the gel with excellent mechanical strength and thermal stability,which improve with increasing gellant and aluminum ***,the gel with 2% agarose and 20% aluminum had the best performance;the storage modulus reached 90647 Pa,which was within the linear viscoelastic region,and the maximum withstand pressure was 111.2 kPa,which was 118.8% greater than that of the pure ***,the gel demonstrates remarkable shear thinning behavior and can undergo gel-sol transformation upon shearing or heating to exceeding 114℃.

关键词： aluminum-water propellant gelled propellant rheological property mechanical strength

Improving hydrogen storage thermodynamics and kinetics of Ce-Mg-Ni-based alloy by mechanical milling with TiF_(3.

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Journal of Magnesium and Alloys 2024年第4期12卷 1593-1607页

作者： Hongwei Shang Wei zhang xin Wei Yaqin li Zeming Yuan Jun li Yanghuan zhang school of Mechanical and Electrical Engineering Chuzhou UniversityChuzhou 239000China Department of Functional Material Research Central Iron and Steel Research InstituteNo.76 Xueyuannan RoadHaidian DistrictBeijing 100081China Key Laboratory of Integrated Exploitation of Bayan-Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China china Rare Earth New Material(Weishan)Co. Ltd.Jining 277600China

Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not *** efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocomposite materials of Mg and *** this experiment,TiF_(3.was selected as an additive,and the mechanical milling method was employed to prepare the experimental *** alloys used in this experiment were the as-cast Ce_(5)Mg_(85)Ni_(10),as-milled Ce_(5)Mg_(85)Ni_(10)and Ce_(5)Mg_(85)Ni_(10)+3.wt.%*** phase transformation,structural evolution,isothermal and non-isothermal hydrogenation and dehydrogenation performances of the alloys were inspected by XRD,SEM,TEM,Sievert apparatus,DSC and *** revealed that nanocrystalline appeared in the as-milled *** with the as-cast alloy,ball milling made the particle dimension and grain size decrease dramatically and the defect density increase *** addition of TiF_(3.made the surface of ball milling alloy particles markedly coarser and more *** milling and adding TiF_(3.distinctly improved the activation and kinetics of the ***,ball milling along with TiF_(3.can decrease the onset dehydrogenation temperature of Mg-based hydrides and slightly ameliorate their thermodynamics.

关键词： Mg-based hydrides TiF_(3. Ball milling Thermodynamics Kinetics

MXenes/CNTs-based hybrids:Fabrications,mechanisms,and modification strategies for energy and environmental applications

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Nano Research 2024年第5期17卷 3429-3454页

作者： Jizhou Jiang Fangyi li Lei Ding Chengxun zhang Arramel xin li school of Environmental Ecology and Biological Engineering School of Chemistry and Environmental EngineeringKey Laboratory of Green Chemical Engineering Process of Ministry of EducationEngineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationNovel Catalytic Materials of Hubei Engineering Research CenterWuhan Institute of TechnologyWuhan 430205China Nano Center Indonesia Jl.PUSPIPTEK Tangerang SelatanBanten 15314Indonesia Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou 510642China

Emerging two-dimensional(2D)layered metal carbide and nitride materials,commonly termed MXenes,are increasingly recognized for their applications across diverse fields such as energy,environment,and *** the past few years,MXenes/carbon nanotubes(CNTs)-based hybrids have attracted extensive attention as an important catalyst in energy and environmental fields,due to their superior multifunctions and mechanical *** review aims to address the fabrication strategies,the identification of the enhancement mechanisms,and recent progress regarding the design and modification of MXenes/CNTs-based hybrids.A myriad of fabrication techniques have been systematically summarized,including mechanical mixing,spray drying,three-dimensional(3.)printing,self-assembly/in-situ growth,freeze drying,templating,hydrothermal methods,chemical vapor deposition(CVD),and ***,the identification of the enhancement mechanisms was thoroughly discussed from the two dimensions of theoretical simulations and in-situ ***,the recent advancements in profound applications of MXenes/CNTs-based hybrids have also been carefully revealed,including energy storage devices,sensors,water purification systems,and microwave *** also underscore anticipated challenges related to their fabrication,structure,underlying mechanisms,modification approaches,and emergent ***,this review offers insights into prospective directions and the future trajectory for these promising *** is expected that this review can inspire new ideas or provide new research methods for future studies.

关键词： MXenes/carbon nanotubes(CNTs)-based hybrids fabrication applications modification strategies

Geological Controls on Seismic indicators of Volcanic Gas Reservoirs:A Case Study from the Changling Fault Depression of Songliao Basin,china

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地学前缘 2009年第S1期16卷 148-149页

作者： lun li,xin zhang school of software,china university of geosciences(Beijing),Beijing {3.

The Songliao basin in northeast china is a Mesozoic rift basin characterized by Mesozoic and Cenozoic hydrocarbon *** Changling fault depression located in the south of the Songliao Basin,

关键词： volcanic gas reservoirs central eruption crevice eruption Changling depression