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Toward a sustainable growth path in Arab economies:an extension of classical growth model
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作者 Amjad Taha Mucahit Aydin +2 位作者 Taiwo Temitope Lasisi Festus Victor Bekun Narayan Sethi 《Financial Innovation》 2023年第1期621-644,共24页
Background/Objectives:Many economies are on the trajectory of alternative growth drivers other than conventional capital and labor.Access to credit facilities is a pertinent indicator of economic growth.In line with t... Background/Objectives:Many economies are on the trajectory of alternative growth drivers other than conventional capital and labor.Access to credit facilities is a pertinent indicator of economic growth.In line with the United Nations Sustainable Development Goals(UNSDGs-8)agenda,the national goal for sustainable development for most economies and Arab economies is no exception.Therefore,the current study adopts a traditional growth model by exploring the relationship between gross domestic product(GDP)per capita,credit for private sectors,ratio of exports,real GDP,and per labor force participants for selected Arab economies annually from 2001 to 2020.Research design:This study leverages the Fourier Kwiatkowski–Phillips–Schmidt–Shin(KPSS)unit root test and second-generation panel econometrics as estimation techniques,such as Westerlund and Edgerton panel cointegration test,and the use of two estimators,namely the augmented mean group(AMG)and common correlated error mean group(CCEMG),to obtain robust results.Findings:Empirical findings from Westerlund and Edgerton panel cointegration tests validate the long-run equilibrium relationship among the outlined variables.Further empirical results indicate that the share of exports is negatively significant with economic growth in countries such as Kuwait,Lebanon,Tunisia,and Jordan.Additionally,savings and labor force participation have a positive relationship with economic growth in individual countries such as Algeria and Bahrain.As per the panel,there is no significant relationship between labor force participation and economic growth.This indicates that the skilled labor force enhanced economic growth.Conclusions:These findings come with inherent far-reaching policy suggestions for economies and panels.Further details on country-specific policy actions are presented in the concluding section. 展开更多
关键词 Arab economies classical growth model Panel econometrics SDG Savings-investment
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics classical Physics Computer 3D model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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GLOBAL EXISTENCE OF CLASSICAL SOLUTION FOR A VISCOUS LIQUID-GAS TWO-PHASE MODEL WITH MASS-DEPENDENT VISCOSITY AND VACUUM 被引量:2
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作者 王振 张卉 《Acta Mathematica Scientia》 SCIE CSCD 2014年第1期39-52,共14页
In this work, we obtain the global existence and uniqueness of classical solu-tions to a viscous liquid-gas two-phase model with mass-dependent viscosity and vacuum in one dimension, where the initial vacuum is allowe... In this work, we obtain the global existence and uniqueness of classical solu-tions to a viscous liquid-gas two-phase model with mass-dependent viscosity and vacuum in one dimension, where the initial vacuum is allowed. We get the upper and lower bounds of gas and liquid masses n and m by the continuity methods which we use to study the compressible Navier-Stokes equations. 展开更多
关键词 viscous liquid-gas two-phase model global classical solution VACUUM mass-dependent viscosity
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Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology
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作者 Sara Benchikh Noureddine Mebarki Dalel Aberkane 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期144-148,共5页
Dynamical behaviors and stability properties of a flat space Friedmann-Robertson-Walker universe filled with pressureless dark matter and viscous dark energy are studied in the context of standard classical and loop q... Dynamical behaviors and stability properties of a flat space Friedmann-Robertson-Walker universe filled with pressureless dark matter and viscous dark energy are studied in the context of standard classical and loop quantum cosmology. Assuming that the dark energy has a constant bulk viscosity, it is found that the bulk viscosity effects influence only the quintessence model case leading to the existence of a viscous late time attractor solution of de- Sitter type, whereas the quantum geometry effects influence the phantom model case where the big rip singularity is removed. Moreover, our results of the Hubble parameter as a function of the redshift are in good agreement with the more recent data. 展开更多
关键词 of on in Dynamical Study of a Constant Viscous Dark Energy model in classical and Loop Quantum Cosmology is that for been FRW
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A Novel Classical Model of the Free Electron
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作者 Arlen Young 《Journal of Modern Physics》 CAS 2022年第7期1117-1127,共11页
Previous models of the free electron using classical physics equations have predicted attributes that are inconsistent with the experimentally observed attributes. For example, the magnetic moment has been calculated ... Previous models of the free electron using classical physics equations have predicted attributes that are inconsistent with the experimentally observed attributes. For example, the magnetic moment has been calculated for the observed spinning electric charge. For the calculated moment to equal the observed moment, the electron would either have to spin at two hundred times the speed of light or have a charge radius two hundred times greater than the classical radius. A similar inconsistency results when the mass derived from the spin angular momentum is compared with the observed mass. A classical model is herein proposed which eliminates the magnetic moment inconsistency and also predicts the radius of the electron. The novel feature of the model is the replacement of a single charge with two opposite charges, one on the outer surface of the electron and the other at the center. 展开更多
关键词 classical Electron model Free Electron Electron Structure Electron Charge Electron Radius Electron Spin Electron Shape Electron Compressibility
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Electron Shape Calculated for the Dual-Charge Dual-Mass Model
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作者 Arlen Young 《Journal of Modern Physics》 CAS 2023年第3期198-207,共10页
A model for the internal structure of the electron using classical physics equations has been previously published by the author. The model employs both positive and negative charges and positive and negative masses. ... A model for the internal structure of the electron using classical physics equations has been previously published by the author. The model employs both positive and negative charges and positive and negative masses. The internal attributes of the electron structure were calculated for both ring and spherical shapes. Further examination of the model reveals an instability for the ring shape. The spherical shape appears to be stable, but relies on tensile or compressive forces of the electron material for stability. The model is modified in this document to eliminate the dependency on material forces. Uniform stability is provided solely by balancing electrical and centrifugal forces. This stability is achieved by slightly elongating the sphere along the spin axis to create a prolate ellipsoid. The semi-major axis of the ellipsoid is the spin axis of the electron, and is calculated to be 1.20% longer than the semi-minor axis, which is the radius of the equator. Although the shape deviates slightly from a perfect sphere, the electric dipole moment is zero. In the author’s previously published document, the attributes of the internal components of the electron, such as charge and mass, were calculated and expressed as ratios to the classically measured values for the composite electron. It is interesting to note that all of these ratios are nearly the same as the inverse of the Fine Structure Constant, with differences of less than 15%. The electron model assumed that the outer surface charge was fixed and uniform. By allowing the charge to be mobile and the shape to have a particular ellipticity, it is shown that the calculated charge and mass ratios for the model can be exactly equal to the Fine Structure Constant and the Constant plus one. The electron radius predicted by the model is 15% greater than the Classical Electron Radius. 展开更多
关键词 Electron Shape classical Electron model Dual-Charge Dual-Mass model Electron Radius Negative Mass Electron Mass Inconsistency Electron Charge Inconsistency Fine Structure Constant
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Rating Score Data Analysis by Classical Test Theory and Many-Facet Rasch Model
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作者 Tsai-Wei Huang Gwo-Jen Guo +1 位作者 William Loadman Fang-Mei Law 《Psychology Research》 2014年第3期222-231,共10页
关键词 h模型 多层面 数据分析 评价 测验 可靠性参数 教育评估 试题难度
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Hypersphere World-Universe Model. Tribute to Classical Physics 被引量:6
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第3期441-470,共30页
This manuscript summarizes the results of Classical Physics before Quantum Mechanics and Hypotheses proposed by classical physicists from the 17th until the beginning of 21st century. We then proceed to unify these re... This manuscript summarizes the results of Classical Physics before Quantum Mechanics and Hypotheses proposed by classical physicists from the 17th until the beginning of 21st century. We then proceed to unify these results into a single coherent picture in frames of the developed Hypersphere World-Universe Model (WUM). The Model proposes 5 types of Dark Matter particles and predicts their masses;models the origin, evolution, and structure of the World and Macroobjects;provides a mathematical framework that ties together a number of Fundamental constants and allows for direct calculation of their values. 展开更多
关键词 classical Physics HYPERSPHERE World-Universe model Medium of the World Dark Matter Particles Gravitoelectromagnetism COSMIC NEUTRINO Background Macroobjects Structure Emergent Phenomena Q-Dependent COSMOLOGICAL Parameters
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Advances in Deep-Learning-based Precipitation Nowcasting Techniques
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作者 ZHENG Qun LIU Qi +1 位作者 LAO Ping LU Zhen-ci 《Journal of Tropical Meteorology》 SCIE 2024年第3期337-350,共14页
Precipitation nowcasting,as a crucial component of weather forecasting,focuses on predicting very short-range precipitation,typically within six hours.This approach relies heavily on real-time observations rather than... Precipitation nowcasting,as a crucial component of weather forecasting,focuses on predicting very short-range precipitation,typically within six hours.This approach relies heavily on real-time observations rather than numerical weather models.The core concept involves the spatio-temporal extrapolation of current precipitation fields derived from ground radar echoes and/or satellite images,which was generally actualized by employing computer image or vision techniques.Recently,with stirring breakthroughs in artificial intelligence(AI)techniques,deep learning(DL)methods have been used as the basis for developing novel approaches to precipitation nowcasting.Notable progress has been obtained in recent years,manifesting the strong potential of DL-based nowcasting models for their advantages in both prediction accuracy and computational cost.This paper provides an overview of these precipitation nowcasting approaches,from which two stages along the advancing in this field emerge.Classic models that were established on an elementary neural network dominated in the first stage,while large meteorological models that were based on complex network architectures prevailed in the second.In particular,the nowcasting accuracy of such data-driven models has been greatly increased by imposing suitable physical constraints.The integration of AI models and physical models seems to be a promising way to improve precipitation nowcasting techniques further. 展开更多
关键词 precipitation nowcasting deep learning neural network classic model large model
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温经汤对大鼠子宫内膜异位症SPARC介导的上皮-间质转化的影响
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作者 庄梦斐 李盼盼 +8 位作者 丁楠 施佑瑾 朱琳 曹阳 谭丽 黄圣惠 杭斐 张婷婷 孙兆贵 《上海中医药杂志》 CSCD 2024年第4期9-18,共10页
目的探讨温经汤对子宫内膜异位症(EMT)大鼠模型富含半胱氨酸的酸性分泌蛋白(SPARC)介导的上皮-间质转化的影响。方法采用手术自体移植子宫内膜块法建立EMT大鼠模型,将建模成功的40只大鼠随机分为模型组(给予质量分数为0.9%的氯化钠溶液1... 目的探讨温经汤对子宫内膜异位症(EMT)大鼠模型富含半胱氨酸的酸性分泌蛋白(SPARC)介导的上皮-间质转化的影响。方法采用手术自体移植子宫内膜块法建立EMT大鼠模型,将建模成功的40只大鼠随机分为模型组(给予质量分数为0.9%的氯化钠溶液10 mL/kg)、孕三烯酮组(给予孕三烯酮溶液0.5 mg/kg)以及温经汤低、中、高剂量组(分别给予温经汤免煎颗粒剂8.19 g/kg、16.38 g/kg、32.76 g/kg),每组各8只,另取7只未手术大鼠作为正常对照组(给予质量分数为0.9%的氯化钠溶液10 mL/kg)。所有大鼠均连续灌胃给药3周后进行取材。腹主动脉取血,采用酶联免疫吸附试验(ELISA)法检测血清中SPARC水平。电子游标卡尺测量异位病灶体积,计算生长抑制率。取下异位病灶组织(正常对照组取下双侧子宫组织)采用免疫组织化学法检测内膜组织中SPARC、锌指转录因子(Snail)、E-钙黏蛋白(E-cadherin)和波形蛋白(Vimentin)的表达,采用Western blot法和RT-qPCR法测定内膜组织中上述因子的蛋白和mRNA相对表达量。结果各治疗组异位病灶的生长抑制率与模型组比较差异均有统计学意义(P<0.05)。与正常对照组比较,模型组血清中SPARC水平显著升高(P<0.05),各治疗组血清中SPARC水平均明显低于模型组(P<0.05)。模型组异位内膜中SPARC、Snail、Vimentin呈高表达,E-cadherin呈低表达,经温经汤治疗后,异位内膜中SPARC、Snail、Vimentin的阳性表达减少,E-cadherin的阳性表达增加。温经汤中、高剂量组和孕三烯酮组异位内膜中SPARC、Snail、Vimentin的蛋白相对表达量均明显低于模型组(P<0.05),E-cadherin的蛋白相对表达量显著高于模型组(P<0.05)。温经汤高剂量组和孕三烯酮组异位内膜中Snail、Vimentin mRNA相对表达量均较模型组显著降低(P<0.05),E-cadherin mRNA相对表达量明显高于模型组(P<0.05)。结论温经汤可以降低EMT大鼠模型血清中SPARC水平,下调异位内膜中SPARC、Snail、Vimentin蛋白和mRNA表达,升高异位内膜中E-cadherin蛋白和mRNA表达,通过调控SPARC介导的上皮-间质转化,从而抑制异位内膜病灶的生长。 展开更多
关键词 子宫内膜异位症 温经汤 上皮-间质转化 大鼠模型 经典名方 中药研究
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Thermodynamic Consistency of Plate and Shell Mathematical Models in the Context of Classical and Non-Classical Continuum Mechanics and a Thermodynamically Consistent New Thermoelastic Formulation 被引量:3
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作者 Karan S. Surana Sri Sai Charan Mathi 《American Journal of Computational Mathematics》 2020年第2期167-220,共54页
Inclusion of dissipation and memory mechanisms, non-classical elasticity and thermal effects in the currently used plate/shell mathematical models require that we establish if these mathematical models can be derived ... Inclusion of dissipation and memory mechanisms, non-classical elasticity and thermal effects in the currently used plate/shell mathematical models require that we establish if these mathematical models can be derived using the conservation and balance laws of continuum mechanics in conjunction with the corresponding kinematic assumptions. This is referred to as thermodynamic consistency of the mathematical models. Thermodynamic consistency ensures thermodynamic equilibrium during the evolution of the deformation. When the mathematical models are thermodynamically consistent, the second law of thermodynamics facilitates consistent derivations of constitutive theories in the presence of dissipation and memory mechanisms. This is the main motivation for the work presented in this paper. In the currently used mathematical models for plates/shells based on the assumed kinematic relations, energy functional is constructed over the volume consisting of kinetic energy, strain energy and the potential energy of the loads. The Euler’s equations derived from the first variation of the energy functional for arbitrary length when set to zero yield the mathematical model(s) for the deforming plates/shells. Alternatively, principle of virtual work can also be used to derive the same mathematical model(s). For linear elastic reversible deformation physics with small deformation and small strain, these two approaches, based on energy functional and the principle of virtual work, yield the same mathematical models. These mathematical models hold for reversible mechanical deformation. In this paper, we examine whether the currently used plate/shell mathematical models with the corresponding kinematic assumptions can be derived using the conservation and balance laws of classical or non-classical continuum mechanics. The mathematical models based on Kirchhoff hypothesis (classical plate theory, CPT) and first order shear deformation theory (FSDT) that are representative of most mathematical models for plates/shells are investigated in this paper for their thermodynamic consistency. This is followed by the details of a general and higher order thermodynamically consistent plate/shell thermoelastic mathematical model that is free of a priori consideration of kinematic assumptions and remains valid for very thin as well as thick plates/shells with comprehensive nonlinear constitutive theories based on integrity. Model problem studies are presented for small deformation behavior of linear elastic plates in the absence of thermal effects and the results are compared with CPT and FSDT mathematical models. 展开更多
关键词 Plate and Shell Mathematical models Energy Functional Thermodynamic Consistency classical Continuum Mechanics Non-classical Continuum Mechanics Internal Rotations Cosserat Rotations Principle of Virtual Work
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传统文化视野下经典-科研-临床一体化的针灸推拿学研究生培养模式探索
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作者 李慧璟 刘雪莹 +3 位作者 李兆霖 刘京丽 张童 解相蕊 《中国中医药现代远程教育》 2024年第20期44-47,共4页
随着中医学各专业研究生招生规模的扩大,研究生培养模式的更新成为中医药人才培养的关键。根据当前国情,各中医院校对中医学研究生的培养更为重视。针灸推拿学研究生是中医药专业的重要力量,因此优化其培养模式、改变复合型针灸推拿学... 随着中医学各专业研究生招生规模的扩大,研究生培养模式的更新成为中医药人才培养的关键。根据当前国情,各中医院校对中医学研究生的培养更为重视。针灸推拿学研究生是中医药专业的重要力量,因此优化其培养模式、改变复合型针灸推拿学专业人才的教育模式势在必行。文章从重视针灸推拿学经典理论、加强科研能力培养、提高临床医疗技能三方面出发,主要介绍以经典-科研-临床为核心的针灸推拿学研究生的培养模式,以更好地培养其中医思维、科研能力及临床技能。 展开更多
关键词 针灸推拿学研究生 培养模式 经典理论 科研
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构建“理实融合”双轨制教学模式——以刑法学经典阅读实践为切入点
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作者 黄明儒 成波 《法学教育研究》 2024年第1期155-172,共18页
刑法学经典阅读的探索与实践,是符合德法兼修的卓越法治人才培养目标的教改尝试。从阅读书目选取到指导阅读、专题研讨、总结点评、创新研究等阶段的具体运用,形成了构建生成性教学、拓展课程方式、打造“师生共同体”等可迁移性经验,... 刑法学经典阅读的探索与实践,是符合德法兼修的卓越法治人才培养目标的教改尝试。从阅读书目选取到指导阅读、专题研讨、总结点评、创新研究等阶段的具体运用,形成了构建生成性教学、拓展课程方式、打造“师生共同体”等可迁移性经验,通过在教学实践中强化学生的“问题意识”、增强教师启发能力、构建长效评价体系三方面发力,以进一步提升教学效果,对于构建“理实融合”双轨制教学模式具有天然优势和价值,这种模式建构有助于法学教育卓越法治人才培养。 展开更多
关键词 “理实融合”双轨制 课程教学模式 经典阅读 卓越法治人才
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利用钒同位素来确定月球形成物质的比例
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作者 石震 戚玉菡 +1 位作者 黄方 丁昕 《高校地质学报》 CAS CSCD 北大核心 2024年第3期371-378,共8页
经典碰撞模型是目前解释月球形成过程的最广为接受的假说,其要求一个约火星大小的撞击体Theia与吸积最后阶段的原始地球相撞,且月球主要来自撞击体Theia。然而关于撞击体对于月球质量贡献的百分比仍缺乏精确的制约。该研究采用地幔橄榄... 经典碰撞模型是目前解释月球形成过程的最广为接受的假说,其要求一个约火星大小的撞击体Theia与吸积最后阶段的原始地球相撞,且月球主要来自撞击体Theia。然而关于撞击体对于月球质量贡献的百分比仍缺乏精确的制约。该研究采用地幔橄榄岩和科马提岩的高精度测量数据,用于重新评估硅酸盐全地球(BSE)的V同位素组成,相比之前的研究,新的数据表明δ^(51)V_(BSE)=-0.91‰±0.02‰(2SE,n=18)。将其重新代入到地月双组分混合模型中,考虑了一个包含撞击前(原地球、Theia)和撞击后(地球、月球、逸出物质)成分的系统,得出现今月球中Theia的质量分数的最佳估计为M_(Theia)=0.8*M_(Mars)时的73%到M_(Theia)=0.45*M_(Earth)时的83%。这与先前的研究相比,降低了对Theia在月球形成中的贡献度约5%。这一结果为经典碰撞模型提供了更可靠的参数,有助于深化对月球形成过程的理解。 展开更多
关键词 经典碰撞模型 硅酸盐全地球 月球 钒同位素
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简版健康素养量表的开发:基于经典测量理论和项目反应理论 被引量:1
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作者 孙小楠 陈珂 +5 位作者 武运筹 汤靖琪 王飞 孙昕霙 贺苗 吴一波 《中国全科医学》 CAS 北大核心 2024年第23期2931-2940,共10页
背景健康素养与健康状况密切相关,目前国内研究多倾向于运用多维度、多条目的健康素养测评工具,尚缺少简便且有效的健康素养测评工具。目的简化健康素养量表并在中国人群中进行心理测量学检验。方法从“中国家庭健康指数调查(2021年)”... 背景健康素养与健康状况密切相关,目前国内研究多倾向于运用多维度、多条目的健康素养测评工具,尚缺少简便且有效的健康素养测评工具。目的简化健康素养量表并在中国人群中进行心理测量学检验。方法从“中国家庭健康指数调查(2021年)”数据中选择18岁及以上人群作为本研究的调查对象,依据纳入与排除标准,最终纳入7449份数据,并随机分为2个样本集,其中样本集1共3680份,样本集2共3769份。对调查对象进行一般资料问卷、12条目健康素养量表(HLS-SF12)、领悟社会支持量表(PSSS)、家庭健康量表(FHS-SF)调查。应用经典测量理论以及项目反应理论中的Mokken模型对HLS-SF12原条目进行筛选,并对精简后的量表进行信效度等验证性分析。结果使用经典测量理论和Mokken模型分别简化出1个9条目版本的量表(HLS-SF9)和1个4条目版本的量表(HLS-SF4)。HLS-SF9与HLS-SF4均无天花板效应、地板效应,二者的Cronbach'sα系数分别为0.913和0.842,折半信度分别为0.871和0.815。HLS-SF4经探索性因子分析提取出1个公因子,累积方差贡献率为67.813%,各条目的因子载荷量均>0.81。HLS-SF9经验证性因子分析结果显示χ^(2)/df=10.844、拟合优度指数(GFI)=0.985、调整拟合优度指数(AGFI)=0.971、规范拟合指数(NFI)=0.986、比较拟合指数(CFI)=0.987和近似误差均方根(RMSEA)=0.051。相关性分析结果显示,HLS-SF9、HLS-SF4与PSSS呈正相关(r=0.367、0.292,P<0.001),与FHS-SF呈正相关(r=0.340、0.237,P<0.001)。HLS-SF9对HLS-SF12的效标效度的一致性水平(ICC)(95%CI)为0.989(0.988~0.999),HLS-SF4效标效度的ICC(95%CI)为0.892(0.886~0.899)。结论简化后的健康素养量表具有良好的信效度,是能够快速测评中国人群健康素养的有效工具,研究者可根据研究精度(HLS-SF9)或测评时间(HLS-SF4)的需求采取针对性选择。 展开更多
关键词 健康素养 条目筛选 经典测量理论 Mokken模型 12条目健康素养量表
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基于DenseNet的经典-量子混合分类模型
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作者 翟飞宇 马汉达 《计算机应用》 CSCD 北大核心 2024年第6期1905-1910,共6页
现有的图像分类模型越来越复杂,计算时所需的硬件资源和计算时间不断增加。针对该问题提出一种基于DenseNet的经典-量子混合分类模型(CQDenseNet模型)。首先,使用一个可在噪声中尺度量子(NISQ)设备上运行的变分量子电路(VQC)作为分类器... 现有的图像分类模型越来越复杂,计算时所需的硬件资源和计算时间不断增加。针对该问题提出一种基于DenseNet的经典-量子混合分类模型(CQDenseNet模型)。首先,使用一个可在噪声中尺度量子(NISQ)设备上运行的变分量子电路(VQC)作为分类器,替换DenseNet全连接层;其次,使用迁移学习,利用在ImageNet数据集上预先训练好的DenseNet模型作为CQDenseNet的预训练模型;最后,将CQDenseNet模型在中草药分类数据集和CIFAR-100数据集上与基准模型AlexNet、GoogLeNet、VGG19、ResNet和DenseNet-169进行对比。实验结果表明,CQDenseNet模型比所有基准模型中表现最好的基准模型:准确率分别提高了2.2、7.4个百分点,精确率分别提高了2.2、7.3个百分点,召回率分别提高了2.2、7.1个百分点,F1值分别提高了2.3、6.4个百分点,说明了经典-量子混合模型的性能优于经典模型。 展开更多
关键词 DenseNet 经典-量子混合模型 图像分类 迁移学习 变分量子电路
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近Bohr速度129Xeq+离子入射Ta靶发射近红外光谱线
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作者 王益军 张颖 +9 位作者 张小安 周贤明 梅策香 梁昌慧 曾利霞 李耀宗 柳钰 向前兰 孟惠 张艳宁 《原子与分子物理学报》 北大核心 2024年第6期84-91,共8页
用动能一定的高电荷态^(129)Xe^(q+)(17≤q≤27)离子,分别入射洁净的Ta靶表面,测量中性化的激发态Xe原子从组态5p^(5)(^(2)P°_(3/2))nl退激到组态5p^(5)(^(2)P°_(3/2))ml’过程中辐射的近红外光谱线.实验结果表明:多激发态的... 用动能一定的高电荷态^(129)Xe^(q+)(17≤q≤27)离子,分别入射洁净的Ta靶表面,测量中性化的激发态Xe原子从组态5p^(5)(^(2)P°_(3/2))nl退激到组态5p^(5)(^(2)P°_(3/2))ml’过程中辐射的近红外光谱线.实验结果表明:多激发态的空心原子退激发射其特征光谱线,部分典型的跃迁按照阶梯方式退激.Xe原子发射的谱线的单粒子荧光产额和激发的Ta原子发射谱线的单粒子荧光产额随入射离子电荷态的增加而增加,其增加的趋势与入射离子携带的势能随电荷态增加的趋势一致.证明在近Bohr速度的能区,经典过垒模型是成立的. 展开更多
关键词 玻尔速度 高电荷态离子 经典过垒模型 近红外光谱线 空心原子
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古典家具复杂三维曲面数据测量与模型重建研究
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作者 董磊 张磊 +1 位作者 许帅康 张荣强 《家具与室内装饰》 北大核心 2024年第8期65-71,共7页
本文旨在对古典家具全息三维信息进行数字化保护,以仿古典家具的陈列台座作为逆向建模案例,分析了逆向工程的特点、流程及关键环节,采用三维激光扫描设备对仿古典家具的表面三维数据进行非接触测量,采用逆向工程软件Geomagic Studio对... 本文旨在对古典家具全息三维信息进行数字化保护,以仿古典家具的陈列台座作为逆向建模案例,分析了逆向工程的特点、流程及关键环节,采用三维激光扫描设备对仿古典家具的表面三维数据进行非接触测量,采用逆向工程软件Geomagic Studio对测量数据进行处理,得到较完整的多边形数据模型;以NURBS曲面重建思想应用Solid Works软件进行实体重建,得到参数化实体结构装配模型,经测定,三维模型的尺寸和装配精度均符合样品原型,有利于对古典家具全息三维信息的数字化保护。 展开更多
关键词 计算机辅助设计 逆向工程 曲面测量 模型重建 古典家具
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AIGC驱动古籍自动摘要研究:从自然语言理解到生成
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作者 吴娜 刘畅 +1 位作者 刘江峰 王东波 《图书馆论坛》 CSSCI 北大核心 2024年第9期111-123,共13页
作为自然语言处理中的关键任务,旨在压缩长文本信息、解决文本信息过载问题。文章以《二十四史》中的人物列传语料为例,从抽取式和生成式方法出发,探索AIGC技术驱动下古籍文本自动摘要应用的可行路径,为古籍资源的创造性转化和创新性发... 作为自然语言处理中的关键任务,旨在压缩长文本信息、解决文本信息过载问题。文章以《二十四史》中的人物列传语料为例,从抽取式和生成式方法出发,探索AIGC技术驱动下古籍文本自动摘要应用的可行路径,为古籍资源的创造性转化和创新性发展提供参考,助力数字人文理念下的古籍内容价值实现。首先基于GujiBERT、SikuBERT、BERT-ancient-Chinese模型进行语义表征,并使用LexRank算法进行重要性排序以抽取摘要。然后利用GPT-3.5-turbo、GPT-4和ChatGLM3模型生成摘要,并构建ChatGLM3和GPT-3.5-turbo微调模型。最后采用信息覆盖率和信息多样性指标对抽取式摘要结果进行评测,采用rouge和mauve指标对生成式摘要结果进行评测。研究表明:SikuBERT在抽取式摘要任务中对古文的语义表征能力和理解能力较强;通用大语言模型在古籍领域的自动摘要能力各有特色,但主旨提炼能力有所欠缺;通过小样本数据集微调GPT-3.5-turbo和ChatGLM3模型能有效提升模型的摘要生成能力。 展开更多
关键词 古籍价值再造 自动摘要 SikuBERT 大语言模型
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单原子Cu催化剂还原燃煤烟气中NO的微观机理研究
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作者 李响 安治全 +1 位作者 朱亚明 王焕然 《煤质技术》 2024年第5期11-17,共7页
单原子催化剂具有高原子利用率与高催化活性并已广泛应用于CO氧化、CO_(2)还原等领域,对单原子Cu催化剂在催化还原NO领域的微观机理研究有助于开发还原氮氧化物的新型单原子催化剂。阐述量子化学计算参数与模型构建,剖析基于Eley-Rideal... 单原子催化剂具有高原子利用率与高催化活性并已广泛应用于CO氧化、CO_(2)还原等领域,对单原子Cu催化剂在催化还原NO领域的微观机理研究有助于开发还原氮氧化物的新型单原子催化剂。阐述量子化学计算参数与模型构建,剖析基于Eley-Rideal(E-R)、Langmuir-Hinshelwood(L-H)吸附机理下的NO还原反应路径及N_(2)O还原反应路径,并对NO还原反应动力学进行分析,以密度泛函理论、经典过渡态理论为依据,探究石墨烯量子点担载单原子Cu催化剂(Cu/G)催化还原燃煤烟气中NO的微观反应机理。结果表明,Cu/G非均相还原NO包括N_(2)O的形成与N_(2)的形成2个阶段。由能垒角度分析,在E-R作用机制下,NO依次被还原生成N_(2)O和N_(2)的控速步骤能垒值为74.5 kJ/mol,小于L-H作用机制控诉步骤能垒值。由动力学角度分析,反应温度的升高提升了NO还原反应的速率。反应过程中活性氧的转移导致石墨烯量子点的消耗,随着活性氧转移速率的减弱,最终导致催化剂失活。单原子Cu催化剂催化还原NO的能垒值较金属Cu团簇能垒值有所降低,说明金属分散性对催化剂的活性产生直接影响,也证明单原子催化在还原NO领域具有潜在的前景。 展开更多
关键词 微观机理 密度泛函理论 单原子催化剂 氮氧化物 经典过渡态理论 模型结构 还原反应路径
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