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Higher-order effects on self-similar parabolic pulse in the microstructured fibre amplifier 被引量:1
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作者 刘伟慈 徐文成 +3 位作者 冯杰 陈伟成 李书贤 刘颂豪 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期1025-1028,共4页
By considering higher-order effects, the properties of self-similar parabolic pulses propagating in the microstructured fibre amplifier with a normal group-velocity dispersion have been investigated. The numerical res... By considering higher-order effects, the properties of self-similar parabolic pulses propagating in the microstructured fibre amplifier with a normal group-velocity dispersion have been investigated. The numerical results indicate that the higher-order effects can badly distort self-similar parabolic pulse shape and optical spectrum, and at the same time the peak shift and oscillation appear, while the pulse still reveals highly linear chirp but grows into asymmetry. The influence of different higher-order effects on self-similar parabolic pulse propagation has been analysed. It shows that the self-steepening plays a more important role. We can manipulate the geometrical parameters of the microstructured fibre amplifier to gain a suitable dispersion and nonlinearity coefficient which will keep high-quality self-similar parabolic pulse propagation. These results are significant for the further study of self-similar parabolic pulse propagation. 展开更多
关键词 self-similar parabolic pulse microstructured fibre amplifier higher-order dispersion nonlinear effect
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Higher Order Multipole Potentials and Electrostatic Screening Effects on Cohesive Energy and Bulk Modulus of Metallic Nanoparticles
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作者 T.Barakat 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第12期1125-1129,共5页
Higher order rnultipole potentials and electrostatic screening effects are introduced to incorporate the dan gling bonds on the surface of a metallic nanopaticle and to modify the coulornb like potential energy terms,... Higher order rnultipole potentials and electrostatic screening effects are introduced to incorporate the dan gling bonds on the surface of a metallic nanopaticle and to modify the coulornb like potential energy terms, respectively. The total interaction energy function for any rnetallic nanoparticle is represented in terms of two- and three-body potentials. The two-body part is described by dipole-dipole interaction potential, and in the three-body part, triple-dipole (DDD) and dipole-dipole-quadrupole (DDQ) terrns are included. The size-dependent cohesive energy and bulk modulus are observed to decrease with decreasing sizes, a result which is in good agreement with the experimental values of Mo and W nanoparticles. 展开更多
关键词 higher order multipole potentials electrostatic screening effect size-dependent cohesive energy size-dependent bulk modulus metallic nanoparticles
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General Solutions of a Higher Order Impulsive Fractional Differential Equation Involving the Riemann-Liouville Fractional Derivatives 被引量:1
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作者 Yuji LIU 《Journal of Mathematical Research with Applications》 CSCD 2020年第2期140-164,共25页
We give general solutions(the explicit solutions) of a class of multi-term impulsive fractional differential equations involving the Riemann-Liouville fractional derivatives. This paper contributes within the domain o... We give general solutions(the explicit solutions) of a class of multi-term impulsive fractional differential equations involving the Riemann-Liouville fractional derivatives. This paper contributes within the domain of impulsive fractional differential equations. The author strongly believes that the article will highly be appreciated by the researchers working in the field of fractional calculus and on fractional differential models. 展开更多
关键词 higher order FRACTIONAL differential equation PIECEWISE continuous solution RiemannLiouville FRACTIONAL DERIVATIVE IMPULSE effect
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Charged Randall-Sundrum Braneworld Type Ⅱ with Higher Order Curvature Corrections from Superstring Arguments and Dominated by Quintessence
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作者 EL-NABULSI Ahmad Rami 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期869-881,共13页
We discuss a new class of RSII braneworld cosmology exhibiting accelerated expansion and dominated by quintessence. It is explicitly demonstrated that the universe expansion history (transition from inflation to dece... We discuss a new class of RSII braneworld cosmology exhibiting accelerated expansion and dominated by quintessence. It is explicitly demonstrated that the universe expansion history (transition from inflation to deceleration epoch to acceleration and effective quintessence era) may naturally occur in such unified theory for some classes of inverse scalar potentials. Besides a decaying effective cosmological constant, the model incorporates an increasing black hole mass, an increasing Maxwellian electrical charge with cosmic time and a time-dependent brahe tension. The cosmological model exhibits several features of cosmological and astrophysical interest for both the early and late universe consistent with recent observations, in particular the ones concerned with the gravitational constants, black holes masses and charges and variation of the gauge coupling parameters with cosmic time. One interesting mark of the constructed model concerns the fact that a black hole mass surrounded by quintessence energy may increase with time even if the horizon disappears. 展开更多
关键词 brane world RSII cosmology higher order curvature corrections black hole black strings effective cosmological constant Maxwellian charge QUINTESSENCE accelerated expansion
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Disorder induced phase transition in magnetic higher-order topological insulator: A machine learning study
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作者 Zixian Su Yanzhuo Kang +2 位作者 Bofeng Zhang Zhiqiang Zhang Hua Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第11期308-315,共8页
Previous studies presented the phase diagram induced by the disorder existing separately either in the higher-order topological states or in the topological trivial states, respectively. However, the influence of diso... Previous studies presented the phase diagram induced by the disorder existing separately either in the higher-order topological states or in the topological trivial states, respectively. However, the influence of disorder on the system with the coexistence of the higher-order topological states and other traditional topological states has not been investigated. In this paper, we investigate the disorder induced phase transition in the magnetic higher-order topological insulator. By using the convolutional neural network and non-commutative geometry methods, two independent phase diagrams are calculated.With the comparison between these two diagrams, a topological transition from the normal insulator to the Chern insulator is confirmed. Furthermore, the network based on eigenstate wavefunction studies also presents a transition between the higher-order topological insulator and the Chern insulator. 展开更多
关键词 DISorder effects CONVOLUTION neural network higher-order TOPOLOGICAL STATES
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Differential Quadrature Method for Bending Problem of Plates with Transverse Shear Effects 被引量:4
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作者 李晶晶 程昌钧 《Journal of Shanghai University(English Edition)》 CAS 2003年第3期228-233,共6页
A differential quadrature (DQ) method for orthotropic plates was proposed based on Reddy' s theory of plates with the effects of the higher-order transverse shear deformations. Wang-Bert's DQ approach was also... A differential quadrature (DQ) method for orthotropic plates was proposed based on Reddy' s theory of plates with the effects of the higher-order transverse shear deformations. Wang-Bert's DQ approach was also further extended to handle the boundary conditions of plates. The computational convergence was studied, and the numerical results were obtained for different grid spacings and compared with the existing results. The results show that the DQ method is fairly reliable and effective. 展开更多
关键词 differential quadrature method higher-order transverse shear deformation effect of grid spacing numerical convergence.
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High-Order BAM, Its Modifications and Performance Analyses
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作者 郑建立 陈松灿 《Journal of China Textile University(English Edition)》 EI CAS 1998年第4期27-30,共4页
Based on Tai’ s high - order bidirectional associative memory ( HOBAM) and Stmposon’ s intraconnected BAM (IBAM) , two Improved models are first presented and discussed in this paper. The improved models not only re... Based on Tai’ s high - order bidirectional associative memory ( HOBAM) and Stmposon’ s intraconnected BAM (IBAM) , two Improved models are first presented and discussed in this paper. The improved models not only retain the advantages of both HOBAM and ISAM but overcome the shortcomings of Kosko’ s BAM also. Secondly their recall stabilities in synchronous and asyn-chronous update modes have been proven by defining corresponding energy functions which decrease as the re-call process proceeds such that the systems can ensure all the training pattern pairs to become local minima of the energy surfaces. Finally with signal - to - noise ratio (SNR) approach, we show that their storage capacities and error correction capabilities are better than that of the HOBAM. 展开更多
关键词 BIDIRECTIONAL ASSOCIATIVE memory ( BAM ) higher - order stability capacity SNR intraconnection neu-ral network
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Dynamics of Controllable Optical Rogue Waves in Presence of Quintic Nonlinearity and Nonlinear Dispersion Effects
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作者 马笑霄 赵立臣 +2 位作者 刘冲 杨战营 杨文力 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第11期701-706,共6页
We analytically study optical rogue waves in the presence of quintic nonlinearity and nonlinear dispersion effects. Dynamics of the rogue waves are investigated through the precise expressions of their peak, valley, t... We analytically study optical rogue waves in the presence of quintic nonlinearity and nonlinear dispersion effects. Dynamics of the rogue waves are investigated through the precise expressions of their peak, valley, trajectory,and width. Based on this, the properties of a few specific rogue waves are demonstrated in detail, and the dynamical evolution of rogue waves can be well controlled under different nonlinearity management. It shows that the peak reaches its maximum and the valley becomes minimized when the width evolves to the minimum value. Moreover, we find that the higher-order effects here achieve balance due to the integrability, and they only influence the rogue waves' trajectory. 展开更多
关键词 rogue WAVES DYNAMICS PROPERTY higher-order effects NONLINEARITY management
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Photon higher-order squeezing effects of the q analogue of a single-mode field interacting with a -type three-level atom
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作者 张慧慧 申华军 +1 位作者 周静涛 刘新宇 《Chinese Physics C》 SCIE CAS CSCD 2009年第8期622-625,共4页
The nonlinear theory of interaction between the q analogue of a single-mode field and a Ξ-type threelevel atom has been established. And the formal solution of the Schrodinger equation in the representation and its a... The nonlinear theory of interaction between the q analogue of a single-mode field and a Ξ-type threelevel atom has been established. And the formal solution of the Schrodinger equation in the representation and its average number are obtained. Then, the photon squeezing effects are studied through numerical calculation. The results show that the q deformation nonlinear action has a lot of influence on the quantum coherence and quantum properties. When q approaches 1, the theory reduces to the common linear theory. 展开更多
关键词 quantum optics quantum properties q deformation higher-order squeezing effects
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两模光场与原子相互作用中光场周期性和频效应-理想Kerr介质腔中非关联双模相干态光场与V型三能级原子相互作用系统中光场的不等阶和压缩效应 被引量:3
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作者 赖振讲 侯洵 +2 位作者 杨志勇 白晋涛 孙中禹 《光子学报》 EI CAS CSCD 北大核心 2002年第12期1425-1429,共5页
利用多模压缩态理论 ,通过数值计算研究了高QKerr介质腔中非关联双模相干态光场与V型三能级原子相互作用系统中双模光场的不等幂次高次和压缩效应 ,分别绘出了两模光场第一模i次方第二模j次方不等幂次和压缩度的第一正交分量 (Sh1 ij) ... 利用多模压缩态理论 ,通过数值计算研究了高QKerr介质腔中非关联双模相干态光场与V型三能级原子相互作用系统中双模光场的不等幂次高次和压缩效应 ,分别绘出了两模光场第一模i次方第二模j次方不等幂次和压缩度的第一正交分量 (Sh1 ij) ,第二正交分量(Sh2 ij)的时间演化曲线 结果表明 :1 )Kerr介质的存在和嵌放在介质中的V型三能级原子是产生双模光场不等阶和压缩效应的物质条件 ,二者缺一不可 2 )腔中光场和原子发生光子交换是导致双模光场不等幂次和压缩效应的微观机制 3)在不考虑坐标度的情况下 ,不同条件下的时间演化曲线呈现非常相似的“崩坍 -复原 -凹谷”式结构 ,且复原区的波型振荡次数及凹谷区的振荡下降和振荡上升型式一样 4)在 χ以及〈n1 〉 ,〈n2 〉不变的条件下 ,不等幂次高次和压缩度时间演化曲线的崩坍 -复原 -凹谷式结构的持续时间随压缩阶次的升高而缩短 ,压缩度随压缩阶数的升高而迅速下降 5 )在平均光子不变 (即〈n1 〉 ,〈n2 〉恒定 ) ,但Kerr介质不同 (即 χ变化 )的条件下 ,不等幂次高次和压缩度曲线的周期随Kerr介质的三阶非线性极化系数 χ的增加而缩短 ,幅度则不受Kerr介质的三阶非线性极化系数变化的影响 6)不等幂次高次和压缩效应的持续时间等强烈地依赖于Kerr介质的? 展开更多
关键词 相互作用 光场周期性和频效应 高Q KERR介质腔 非关联双模相干态光场 Ⅴ型三能级原子 不等幂次高次和压缩效应 不等害虫次高次和压缩度 量子光学
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有限维希尔伯特空间偶奇q-相干态的高阶反聚束效应(英文) 被引量:1
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作者 张勇 王维玺 《量子光学学报》 CSCD 2000年第4期144-148,共5页
构造了有限维希尔伯特空间偶奇q-相干态,并通过数值计算研究了它们的高阶反聚束效应,分析了空间维数和形变参数q对反聚京效应的影响。
关键词 偶奇q-相干态 高阶反聚束效应 量子光学
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使用智能工具会对学生高阶思维产生影响吗——基于35项实验与准实验的元分析
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作者 姚颖 胡凡刚 卜可可 《现代基础教育研究》 2026年第1期43-50,共8页
在人工智能技术迅速发展的背景下,高阶思维已成为教育改革的重要目标,然而智能工具促进高阶思维的效果仍存争议。文章采用元分析方法整合35项实验与准实验研究,结果表明,智能工具对学生高阶思维具有显著正向作用,且效应量达到较高水平... 在人工智能技术迅速发展的背景下,高阶思维已成为教育改革的重要目标,然而智能工具促进高阶思维的效果仍存争议。文章采用元分析方法整合35项实验与准实验研究,结果表明,智能工具对学生高阶思维具有显著正向作用,且效应量达到较高水平。性别、学段、实验周期、学科与工具类型等因素与干预效果密切相关。据此提出开展差异化智能应用、合理安排使用周期、加强学科融合并精准匹配工具功能等建议,为智能时代高阶思维教学提供实证依据。 展开更多
关键词 智能工具 高阶思维 元分析 教育应用 调节效应
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SU(2)q-奇偶相干叠加态的高阶压缩效应和高阶反聚束效应
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作者 张慧慧 白鲜萍 +2 位作者 王维玺 李瑞芳 张艳霞 《内蒙古大学学报(自然科学版)》 CAS CSCD 北大核心 2003年第4期385-389,共5页
运用q代数进一步计算了在SU(2)q-奇偶相干叠加态下的高阶期望值,通过理论计算与实验研究了其非经典效应.发现其二阶压缩效应无论q取什么值都存在;其高阶反聚束效应由于形变参数的影响具有更加丰富的结构.
关键词 高阶压缩效应 高阶反聚束效应 高阶期望值
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增强型整体-局部高阶理论四边形单元层合板自由边分析 被引量:1
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作者 徐铮 吴振 《沈阳航空航天大学学报》 2013年第3期55-60,共6页
基于增强型整体-局部高阶理论,构造了四节点四边形单元并分析复合材料自由边拉伸问题。本理论预先满足层合板面内位移和层间应力连续条件及层合板上下自由表面条件,未知变量个数不依赖于层合板的层数。精化四节点四边形单元满足单元间C... 基于增强型整体-局部高阶理论,构造了四节点四边形单元并分析复合材料自由边拉伸问题。本理论预先满足层合板面内位移和层间应力连续条件及层合板上下自由表面条件,未知变量个数不依赖于层合板的层数。精化四节点四边形单元满足单元间C1弱连续性条件。数值结果表明,基于增强型整体-局部高阶理论构造的四边形单元能够精确分析自由边拉伸问题。层间横向剪切应力能够直接从本构方程中计算得出,而横向法应力则需在一个单元内使用局部三维平衡方程。 展开更多
关键词 复合材料层合板 自由边效应 增强型整体-局部高阶理论 精化四边形单元 层间应力
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生成式人工智能赋能大学生高阶思维能力培养的途径与效果
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作者 张伟平 刘欣欣 《当代教育理论与实践》 2025年第6期49-55,共7页
数智时代背景下,生成式人工智能(GAI)为数智人才培养带来了新机遇与新挑战。基于学术界已有研究,采用文献综述法,从途径与效果两方面分析生成式人工智能赋能下的大学生高阶思维能力培养。研究发现:生成式人工智能主要通过原生对话和技... 数智时代背景下,生成式人工智能(GAI)为数智人才培养带来了新机遇与新挑战。基于学术界已有研究,采用文献综述法,从途径与效果两方面分析生成式人工智能赋能下的大学生高阶思维能力培养。研究发现:生成式人工智能主要通过原生对话和技术融合两个途径赋能大学生高阶思维能力培养。学术界实证研究表明:生成式人工智能能够显著提高大学生高阶思维能力,如批判性思维能力、问题解决能力、创造性思维能力等。 展开更多
关键词 生成式人工智能 高阶思维能力 途径 效果
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融合高阶网络与功能共振的危险品道路运输事故关键因素耦合
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作者 任翠萍 李晓飞 谢逢洁 《公路交通科技》 北大核心 2025年第12期24-36,共13页
[目标]关键因素辨识是遏制事故的重要途径,对事故的发生起着决定性作用;而关键因素间的耦合作用在加剧事故发展的同时,对事故的演化及后果起到重要作用。为精准辨识关键因素并定量表征关键因素间的耦合作用关系,以危险品道路运输事故为... [目标]关键因素辨识是遏制事故的重要途径,对事故的发生起着决定性作用;而关键因素间的耦合作用在加剧事故发展的同时,对事故的演化及后果起到重要作用。为精准辨识关键因素并定量表征关键因素间的耦合作用关系,以危险品道路运输事故为研究对象,提出了融合高阶网络(HON)与功能共振分析法(FRAM)的关键因素耦合作用分析方法。[方法]首先,基于事故致因高阶网络中的重叠社团划分提取事故关键节点及其作用关系网络,构建关键节点间的HON-FRAM模型。然后,定量分析节点间性能变化和潜在耦合关系,以识别易受耦合变异影响的链路及交互作用机理。最后,以2017至2021年中国发生的危险品道路运输事故为例进行实证分析。[结果]危险品道路运输系统中存在10条高耦合功能失效和断裂链路,其中人因功能和车辆功能是易产生失效链条的重要致因功能。操作不当是最易导致事故发生的人为致因,碰撞和翻车是最易引发二次事故的高耦合初始事故类型节点,罐体破损是事故演化的重要中转节点。[结论]所建立模型有效模拟危险品道路运输事故中关键因素间的交互作用机理,识别了关键致因及其高耦合链路。 展开更多
关键词 智能交通 耦合作用 高阶网络 功能共振分析法 危险品 道路运输事故
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圆形夹芯结构空心梁弯曲与自由振动分析
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作者 吴晓 肖珍 明勇 《中南大学学报(自然科学版)》 北大核心 2025年第5期1839-1850,共12页
为解决圆形夹芯结构空心梁弯曲挠度及自振基频的求解问题。基于高阶剪切变形理论,根据圆形夹芯结构空心梁几何方程、静力平衡方程以及边界条件推导了梁挠曲线通用方程,得出了均布载荷作用下两端简支、一端简支一端固支、两端固支、悬臂... 为解决圆形夹芯结构空心梁弯曲挠度及自振基频的求解问题。基于高阶剪切变形理论,根据圆形夹芯结构空心梁几何方程、静力平衡方程以及边界条件推导了梁挠曲线通用方程,得出了均布载荷作用下两端简支、一端简支一端固支、两端固支、悬臂这4种约束条件下的挠曲线方程。利用Galerkin原理,推导了这4种约束条件下的圆形夹芯结构空心梁自振基频表达式。运用相关算例讨论了高阶剪切变形理论求解圆形夹芯结构空心梁挠度和自振基频的计算精度,并分析了剪切变形和转动惯量的影响。研究结果表明:高阶剪切变形理论计算结果与有限元法计算结果基本一致,说明本方法在求解圆形夹芯结构空心梁弯曲和自由振动时具有较高的计算精度;随着跨径比的减小,剪切变形对圆形夹芯结构空心梁挠度和自振基频的影响均呈增大的趋势;在不同约束条件下,其影响效应也不一致。相对于剪切变形的影响,转动惯量对圆形夹芯结构空心梁自振基频的影响可忽略不计,但当跨径比小于或等于5时,应考虑转动惯量的影响。研究结果为求解夹芯空心梁挠度和自振基频问题提供了一种更为简便的方法,便于程式化和推广应用。 展开更多
关键词 圆形夹芯结构空心梁 弯曲挠度 自振基频 高阶剪切 剪切效应 转动惯量
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教育数字化转型中智能技术对教学效果的影响研究
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作者 霍庆路 《中国科技纵横》 2025年第7期144-146,共3页
教育数字化转型是利用先进数字化技术推动教育主体转变业务模式、组织架构、文化内涵的一系列变革性措施,旨在持续优化教育组织构想,为教育增添更具差异性的价值。本文通过文献分析和案例研究,探讨智能技术对教学效果的影响。研究结果表... 教育数字化转型是利用先进数字化技术推动教育主体转变业务模式、组织架构、文化内涵的一系列变革性措施,旨在持续优化教育组织构想,为教育增添更具差异性的价值。本文通过文献分析和案例研究,探讨智能技术对教学效果的影响。研究结果表明,智能技术在提高学习效率、促进个性化学习和增强学习互动性方面具有显著优势。 展开更多
关键词 教育数字化转型 智能技术 教学效果 个性化学习 高阶思维
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深度学习视角下的数学课程有效教学策略探微
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作者 常雪茹 《成才之路》 2025年第12期97-100,共4页
深度学习视角下的数学课程有效教学,具有学习方式的自主性、学习内容的梯级性、学习成果的真实性、学习评价的多维性等特点,以解决复杂问题为出发点,以核心素养为架构,以培养高阶思维为核心,有利于提升学生综合能力,促进学生全面发展。... 深度学习视角下的数学课程有效教学,具有学习方式的自主性、学习内容的梯级性、学习成果的真实性、学习评价的多维性等特点,以解决复杂问题为出发点,以核心素养为架构,以培养高阶思维为核心,有利于提升学生综合能力,促进学生全面发展。深度学习视角下的数学课程有效教学要创设教学情境、引发认知冲突,融入趣味元素、丰富数学感知,组织实验探究、培养高阶思维,通过迁移应用、促进知识内化,多元评价、推动反思与创新。 展开更多
关键词 深度学习 小学数学 有效性 教学策略 高阶思维 知识内化
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