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基于场景理解的彩色融合图像质量主观评价

电光与控制 2024年第6期31卷 81-86页

作者：何炳阳张宇肖逸凡李阳年陈露祁雪燕中国华阴兵器试验中心陕西渭南714000 联勤保障部队预备役旅重庆400000

基于场景理解的彩色融合图像质量用于衡量观察者通过融合图像准确理解场景内容的难易程度,通常采用主观评价的方式获得。为了提升主观评价的稳定性,以村庄场景为例,将基于场景理解的彩色融合图像质量这一较抽象的概念具体化为区域分割... 详细信息

基于场景理解的彩色融合图像质量用于衡量观察者通过融合图像准确理解场景内容的难易程度,通常采用主观评价的方式获得。为了提升主观评价的稳定性,以村庄场景为例,将基于场景理解的彩色融合图像质量这一较抽象的概念具体化为区域分割和景物辨别两项性能指标,组织15名观察者主观评价了42幅不含热目标的彩色融合图像的质量。使用结构方程模型对主观评分值进行分析,建立了基于场景理解的彩色融合图像质量的预测模型,并验证了预测模型的正确性。结果表明,在村庄场景下,基于场景理解的彩色融合图像质量可由颜色协调性和颜色自然感2个因素预测,并更多地表现为景物辨别性能。

关键词：彩色融合图像主观评价场景理解预测模型结构方程模型

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Process-microstructure-properties of CuAlNi shape memory alloys fabricated by laser powder bed fusion

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Journal of Materials Science & Technology 2023年第21期152卷 1-15页

作者： Yankun Zhang Lianyong Xu Lei Zhao Danyang Lin Minqian Liu xueyan qi Yongdian Han School of Materials Science and Engineering Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Advanced Joining Technology Tianjin 300350China State Key Laboratory of Engines Tianjin UniversityTianjin 300350China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

Cu-based shape memory alloys(SMAs)show great potential in the application of high temperature,but their performance improvement combining with additive manufacturing is still *** this paper,nearly defect-free(99.7%relative density)CuAlNi SMAs with two types of thermal-induced martensites,18R and 2H,were successfully fabricated by laser powder bed fusion(LPBF).The remelting printing strat-egy with systematic optimization framework including densification and printability analysis was used to get optimal process *** twin-related self-accommodation structure with long period stacking order substructure was formed during additive manufacturing *** as-build samples show excel-lent mechanical properties(ultimate compressive strength of 1593±10 MPa and large fracture strain of 23.0%±0.1%)with double-yielding,and outstanding shape memory effect,with maximum recoverable strain of 3.39% and nearly 100%recovery rate under compressive strain not exceeding 6%.Furthermore,the microstructural evolution in LPBF involving remelting,martensitic transformation,and 2H marten-site was *** result not only builds the microstructure framework involving high reflectivity alloys and martensitic transformation but also provides insight into the applicability of LPBF process in producing Cu-based SMAs.

关键词： Shape memory alloys Cu-based Laser powder bed fusion Martensitic transformation Microstructural evolution

Friction between Strongly Compressed Polymer Brushes

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Chinese Journal of Polymer Science 2024年第9期42卷 1368-1374,I0008页

作者： qi Liao Institute of Chemistry Chinese Academy of SciencesBejing 100190China

We present the results of molecular dynamics simulations of steady shear between a pair of neutral polymer brushes,as well as a pair of charged polymer brushes in the strongly compressed *** results of the molecular dynamic simulations of neutral and polyelectrolyte brushes in implicit solvent including normal forces,shear forces,viscosities and friction coefficients as a function of separation between brushes,are presented in the *** comparison of the simulation results of neutral and charged brushes shows that the charged brushes is in the quasi-neutral regime,and the dependence of viscosity on the separation distance show the similar power law of neutral *** simulation results confirm that the implicit solvent simulations of polyelectrolyte brushes that ignore hydrodynamics interaction are in agreement with the scaling predictions qualitatively because of screening of hydrodynamic interaction and long-range electrostatic interactions on the correlation length *** of neutral and charged brushes show the lubrication properties that the friction coefficient decreases with the separation decreases at enough large ***,a maximum of friction coefficients is observed for polyelectrolyte brushes,which is in contrast to the neutral brushes with monotonical dependence.

关键词： Polymer brush Frictions coefficient Polyelectrolyte Lubrication

Recent advances in multifunctional shape memory photonic crystals and practical applications

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Nano Research 2024年第1期17卷 79-96页

作者： Yong qi Shufen Zhang State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China

Shape memory photonic crystals(SMPCs)are smart composite materials with changeable structural color integrated by shape memory polymer and photonic *** can produce one or more temporary shapes through nanoscale deformation,memorizing current *** can be recovered to their original shapes or some intermediate states under external stimuli,accompanied by the variation of structural *** porous carriers with built-in sensing properties,SMPCs promoted the interdisciplinary development of nanophotonic technology in materials science,environmental engineering,biomedicine,chemical engineering,and ***,the recent progress on multifunctional SMPCs and practical applications,including traditional and cold programmable SMPCs,is summarized and *** primary concern is shape programming at the nanoscale that has demonstrated numerous attractive functions,including smart sensing,ink-free printing,solvent detection,reprogrammable gradient wetting,and controllable bubble transportation,under variations of the surface *** aims to figure out the nanoscale shape memory effects on structural color conversion and additional performance,inspiring the fabrication of the next generation of ***,perspectives on future research directions and applications are also *** is believed that multifunctional SMPCs are powerful nanophotonic tools for the interdisciplinary development of numerous disciplines in the future.

关键词： photonic crystal shape memory structural color cold programmable shape recovery

Adaptive sampling for corrugated plate digitization using a laser displacement sensor

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Science China(Technological Sciences) 2024年第5期67卷 1510-1523页

作者： WU ChengXing qi qi CHEN BaiJin YANG JiXiang DING Han State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

The surface quality of a corrugated plate directly determines the heat transfer property of the thermal power mechanical *** detection methods are impractical for real-world production,being slow and *** contrast,the point laser displacement sensor,employing the optical triangle method,emerges as a promising device for assessing parts with variable curvature and highly reflective *** its benefits,high-density sampling by an innate frequency introduces challenges such as data redundancy and a poor signal-to-noise ratio,potentially affecting the efficiency and precision of subsequent data *** address these challenges,adjustable frequency data sampling has been developed for this sensor,allowing adaptive sampling for corrugated plate *** process begins with surface digitization to extract discrete points,which are transformed into intersection curves using the B-spline fitting ***,dominant points are identified,considering multigeometric constraints for curvature and arch ***,the sampling signal is adjusted based on the distribution information of dominant *** results indicate that the proposed method effectively minimizes redundant sampling without compromising the accurate capture of essential geometric features.

关键词： corrugated plate laser displacement sensor adaptive sampling dominant point curvature arch height

Geometric Constraints for Global Regularity of 3D Shear Thickening Fluids

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 205-210页

作者： Jia-qi Yang Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China

We consider the relation between the direction of the vorticity and the global regularity of 3D shear thickening *** is showed that a weak solution to the non-Newtonian incompressible fluid in the whole space is stron... 详细信息

关键词： direction of the vorticity non-Newtonian fluid global regularity

Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： Zhao-yang Yin qi-chi Le Yan-chao Jiang Da-zhi Zhao qi-yu Liao qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

Cosmological Constraints on Neutrino Masses in Light of JWST Red and Massive Candidate Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 7-12页

作者： Jian-qi Liu Zhi-qi Huang Yan Su School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Zhuhai 519082China

The overabundance of the red and massive candidate galaxies observed by the James Webb Space Telescope(JWST)implies efficient structure formation or large star formation efficiency at high redshift z~*** the scenario of a low or moderate star formation efficiency,because massive neutrinos tend to suppress the growth of structure of the universe,the JWST observation tightens the upper bound of the neutrino *** A cold dark matter cosmology and a star formation efficiency∈[0.05,0.3](flat prior),we perform joint analyses of Planck+JWST and Planck+BAO+JWST,and obtain improved constraints∑m_(ν)<0.196 eV and ∑m_(ν)+<0.111 eV at 95% confidence level,*** on the above assumptions,the inverted mass ordering,which implies ∑m_(ν)≥0.1 eV,is excluded by Planck+BAO+JWST at 92.7% confidence level.

关键词： (cosmology:)cosmological parameters galaxies:abundances galaxies:formation neutrinos

Public transport inclusion and active aging: A systematic review on elderly mobility

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 312-347页

作者： Na Zhang qi Yang School of Humanities Chang'an UniversityXi'an 710064China School of Transportation Engineering Chang'an UniversityXi'an 710064China School of Economics and Management Chang'an UniversityXi'an 710064China

Global aging has brought attention to addressing the elderly mobility dilemma,and a commitment to address inclusive transport in *** inclusion for older adults aims at establishing an age-friendly transport *** a direct policy goal and promoting active aging as an indirect social goal,to help older populations gain access to transport and social *** on the analysis of scientific knowledge mapping over the past 30 years,this study visualizes the hotspots and trends in elderly mobility *** a qualitative analysis of 138 papers,this paper reviews the theoretical foundations for transport inclusion and three themes of elderly mobility research,proposes a framework for public transport(PT)inclusion research as well as future research *** study suggests that transport inclusion can help enhance elderly health,social participation,and subjective *** can improve their travel opportunities for active aging in four ways:opportunity accessibility,physical accessibility,age-friendly informationalization,and cost *** research should pay attention to examining the mechanism of perceived transport inclusion on active aging,expanding the multilevel research space of the capability approach(CA),and exploring the subjectiveobjective integrated research model for PT *** research contributes to the overall knowledge of the theoretical and empirical researches on PT inclusion for the elderly and promotes the integrated application of interdisciplinary knowledge in the field.

关键词： Transportation engineering Elderly mobility Transport-related social exclusion Transport inclusion Active aging