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双问教学法在智慧课堂教学设计中的研究与应用 被引量:4
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作者 张立巍 《吉林化工学院学报》 CAS 2020年第4期1-8,76,共9页
智慧课堂是教育现代化背景下的新型课堂组织形式,必然要求新型教学方法与之相适应。双问教学法以成果导向理念、学习金字塔理论和教育现代化分层理论为指导,形成以学生为中心、以输出式学习为重心、以教育与信息化技术相结合为核心的教... 智慧课堂是教育现代化背景下的新型课堂组织形式,必然要求新型教学方法与之相适应。双问教学法以成果导向理念、学习金字塔理论和教育现代化分层理论为指导,形成以学生为中心、以输出式学习为重心、以教育与信息化技术相结合为核心的教学设计理念。在内容体系上,双问教学法与认知规律和人才培养目标三个维度相契合,以学生“2+2”个性化学习活动和师生“2+2”精准化学习活动助推智慧课堂的有效建立。设计案例和成绩对比法、AHP法、实证研究法对双问教学法的效果给出了佐证和正向评价,体现了该创新教学法的高度有效性。 展开更多
关键词 双问教学法 智慧课堂 一问知识 二问应用 认知规律
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Oscillatory Criteria for a Class of Boundary Value Problem of Nonlinear Hyperbolic Equations *L
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作者 王培光 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期20-24,共5页
Aim To study a class of boundary value problem of hyperbolic partial functional differential equations with continuous deviating arguments. Methods An averaging technique was used. The multi dimensional problem was... Aim To study a class of boundary value problem of hyperbolic partial functional differential equations with continuous deviating arguments. Methods An averaging technique was used. The multi dimensional problem was reduced to a one dimensional oscillation problem for ordinary differential equations or inequalities. Results and Conclusion The known results of oscillation of solutions for a class of boundary value problem of hyperbolic partial functional differential equations with discrete deviating arguments are generalized, and the oscillatory criteria of solutions for such equation with two kinds of boundary value conditions are obtained. 展开更多
关键词 continuous deviating arguments hyperbolic equation boundary value problem OSCILLATION
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小学高年级数学“问题式”自主双向探究
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作者 相莉 《数学学习与研究》 2019年第19期107-107,共1页
教师引导农村小学生主动、自主学习,把个人自学、小组交流、全班讨论、教师指点等有机地结合起来,改善教学方式,激发学生的学习热情,挖掘个体学习潜能,促使学生主动知识建构,在互补中共同提高的学习方式.
关键词 小组 双问 合作 探究 学习
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The Global Uniqueness of Solutions for a Class of Inverse Problem in 1-D Wave Equations of Hyperbolic Type 被引量:1
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作者 叶留青 司清亮 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期107-110,共4页
This paper has given the global uniquene ss theory of solutions for a class of inverse problem in 1_D Wave equation of hype rbolic type.
关键词 D Wave equations of hyperbolic inverse proble m global uniqueness
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22项双监管措施强化检修施工安全
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作者 孔洪伟 《石油化工建设》 2020年第2期79-82,共4页
以风险辨识为核心,以施工单位和业主单位之间双向安全监管为手段,在石油化工检维修项目施工策划阶段,实行双界面、双隔离、双确认、双培训、双面试、双协议、双审核、双交底、双辨识和双验收;在检维修项目施工过程中,实行两化、双确认... 以风险辨识为核心,以施工单位和业主单位之间双向安全监管为手段,在石油化工检维修项目施工策划阶段,实行双界面、双隔离、双确认、双培训、双面试、双协议、双审核、双交底、双辨识和双验收;在检维修项目施工过程中,实行两化、双确认、双错、双硬、双封闭、双检测、双监管、双监护、双保护、双核实、双应急和双问责,有效降低作业风险,保障检修工程安全。 展开更多
关键词 双隔离 双确认 双辨识 双检测 双问
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22项双监管措施强化检修施工安全
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作者 孔洪伟 《石油化工建设》 2019年第S01期48-50,共3页
以风险辨识为核心,以施工单位和业主单位之间双向安全监管为手段,在石油化工检维修项目施工策划阶段,实行双界面、双隔离、双确认、双培训、双面试、双协议、双审核、双交底、双辨识和双验收;在检维修项目施工过程中,实行两化、双确认... 以风险辨识为核心,以施工单位和业主单位之间双向安全监管为手段,在石油化工检维修项目施工策划阶段,实行双界面、双隔离、双确认、双培训、双面试、双协议、双审核、双交底、双辨识和双验收;在检维修项目施工过程中,实行两化、双确认、双错、双硬、双封闭、双检测、双监管、双监护、双保护、双核实、双应急和双问责,有效降低作业风险,保障检修工程安全。 展开更多
关键词 双隔离 双确认 双辨识 双检测 双问
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应用广泛的会议电视技术
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《国际广播电视技术》 1998年第5期58-58,57,共2页
关键词 会议电视技术 应用 双问 即时可视度交流
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Blow-up of Solution for a Nonlinear Hyperbolic Equation
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作者 陈翔英 刘维先 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期106-110,共5页
In this paper, the existence and uniqueness of the local generalized solution of the initial boundary value problem for a nonlinear hyperbolic equation are proved by the contraction mapping principle and the sufficien... In this paper, the existence and uniqueness of the local generalized solution of the initial boundary value problem for a nonlinear hyperbolic equation are proved by the contraction mapping principle and the sufficient conditions of blow_up of the solution in finite time are given. 展开更多
关键词 nonlinear hyperbolic equation initial boundary value problem local generalized solution blow_up of solution
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Existence and uniqueness of a class of double pyramidal central configurations in six-body problems 被引量:1
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作者 LIUXuefei 《Journal of Chongqing University》 CAS 2004年第1期97-101,共5页
Under the necessary conditions for a double pyramidal central configuration with a diamond base to exist in the real number space, the existence and uniqueness of such configurations were studied by employing combined... Under the necessary conditions for a double pyramidal central configuration with a diamond base to exist in the real number space, the existence and uniqueness of such configurations were studied by employing combinedly the algebraic method and numerical calculation. It is found that there exists a planar curl triangle region G in a square Q such that any point in G and given by the ratio of the two diagonal lengths of the diamond base and the ratio of one diagonal length of the base to the height of the double pyramid configuration determines a unique double pyramid central configuration, while all points in Q-G have no referance to any central configuration. 展开更多
关键词 body problem double pyramidal central configuration existence and uniqueness
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On the Singular Biharmonic Problems Involving Critical Sobolev Exponents
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作者 胡丽平 周世国 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第3期395-401,共7页
Abstract: Let Ω belong to R^N be a smooth bounded domain such that 0 ∈ Ω, N ≥ 5, 2^* :2N/N-4 is the critical Sobolev exponent, and f(x) is a given function. By using the variational methods, the paper proves ... Abstract: Let Ω belong to R^N be a smooth bounded domain such that 0 ∈ Ω, N ≥ 5, 2^* :2N/N-4 is the critical Sobolev exponent, and f(x) is a given function. By using the variational methods, the paper proves the existence of solutions for the singular critical in the homogeneous problem △^u-μ u/{x}^4=|μ|^2*-2u+f(x) with Dirichlet boundary condition on 偏dΩ under some assumptions on f(x) and μ. 展开更多
关键词 biharmonic equation critical Sobolev exponents COMPACTNESS variational methods
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Global Structure Stability of Riemann Solution of Quasilinear Hyperbolic System of Conservation Law in Presence of Boundary:Shocks and Contact Discontinuities
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作者 JIN Cui-Lian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1027-1032,共6页
In this paper, we investigate a class of mixed initial-boundary value problems for a kind of n × n quasilinear hyperbolic systems of conservation laws on the quarter plan. We show that the structure of the pieeew... In this paper, we investigate a class of mixed initial-boundary value problems for a kind of n × n quasilinear hyperbolic systems of conservation laws on the quarter plan. We show that the structure of the pieeewise C^1 solution u = u(t, x) of the problem, which can be regarded as a perturbation of the corresponding Riemann problem, is globally similar to that of the solution u = U(x/t) of the corresponding Riemann problem. The piecewise C^1 solution u = u(t, x) to this kind of problems is globally structure-stable if and only if it contains only non-degenerate shocks and contact discontinuities, but no rarefaction waves and other weak discontinuities. 展开更多
关键词 Riemann problem hyperbolic system conservation laws global structure stability
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Reconfiguration of Spacecraft Cluster Based on Distributed Local Information
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作者 YU Binggu WANG Shuquan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第4期704-712,共9页
The reconstruction of spacecraft cluster based on local information and distributed strategy is investigated.Each spacecraft is an intelligent individual that can detect information within a limited range and can dete... The reconstruction of spacecraft cluster based on local information and distributed strategy is investigated.Each spacecraft is an intelligent individual that can detect information within a limited range and can determine its behavior based on surrounding information.The objective of the cluster is to achieve the formation reconstruction with minimum fuel consumption.Based on the principle of dual pulse rendezvous maneuver,three target selection strategies are designed for collision avoidance.Strategy-1 determines the target point’s attribution according to the target’s distance when the target point conflicts and uses a unit pulse to avoid a collision.Strategy-2 changes the collision avoidance behavior.When two spacecraft meet more than once,the strategy switches the target points of the two spacecraft.In Strategy-3,the spacecraft closer to the target has higher priority in target allocation.Strategy-3 also switches the target points when two spacecraft encounter more than once.The three strategies for a given position,different completion times,and random position are compared.Numerical simulations show that all three strategies can accomplish the spacecraft cluster's reconfiguration under the specified requirements.Strategy-3 is better than Strategy-1 in all simulation cases in the sense of less fuel consumption with different completion times and given location,and it is more effective than Strategy-2 in most of the completion time.With a random initial position and given time,Strategy-3 is better than Strategy-1 in about 70%of the cases and more stable. 展开更多
关键词 spacecraft cluster formation reconstruction relative Lambert problem two-impulse rendezvous distributed maneuver
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Existence and uniqueness for a class of nine-bodies central configurations
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作者 刘学飞 《Journal of Chongqing University》 CAS 2006年第1期53-56,共4页
On some necessary conditions for double pyramidal central configurations with concave heptagon for any given ratio of masses, the existence and uniqueness of a class of double pyramidal central configurations with con... On some necessary conditions for double pyramidal central configurations with concave heptagon for any given ratio of masses, the existence and uniqueness of a class of double pyramidal central configurations with concave heptagon base for nine-body problems is proved in this paper, and the range of the ratio cr of the circularity radius of the heptagon to the half-height of the double pyramidal central configuration involved in this class configurations is obtained, which is in the interval (√3/3,1.099 600 679), and the configuration involved in the bodies with any σ∈ (√3/3, 1.099 600 679) can form a central configuration which is a uniquely central configuration is proved. 展开更多
关键词 nine-body problem existence and uniqueness concave heptagon base double pyramidal central configuration.
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Cauchy Problem for the Nonlinear Double Dispersive Wave Equation
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作者 郭基风 李红 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第3期415-425,共11页
This paper concerns with the Cauchy problem for the nonlinear double dispersive wave equation. By the priori estimates and the method in [9], It proves that the Cauchy problem admits a unique global classical solution... This paper concerns with the Cauchy problem for the nonlinear double dispersive wave equation. By the priori estimates and the method in [9], It proves that the Cauchy problem admits a unique global classical solution. And by the concave method, we give sufficient conditions on the blowup of the global solution for the Cauchy problem. 展开更多
关键词 Cauchy problem double dispersive wave equation global classical solution BLOWUP
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Regenerative Strategy for Sum-rate Enhancement in Bi-directional Three-node Cooperation
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作者 胡宁 《High Technology Letters》 EI CAS 2009年第2期151-154,共4页
In bi-directional three-node cooperation, one regenerative strategy with network coding and power optimization is proposed for system sum-rate under a total energy constraint. In this paper, the network coding and pow... In bi-directional three-node cooperation, one regenerative strategy with network coding and power optimization is proposed for system sum-rate under a total energy constraint. In this paper, the network coding and power optimization are applied to improve system sum-rate. But max-rain optimization problem in power allocation is a NP-hard problem. In high Signal-to-Noise Ratio regime, this NP-hard problem is transformed into constrained polynomial optimization problem, which can be computed in polynomial time. Although it is a suboptimal solution, numerical simulations show that this strategy enhances the system sum-rate up to 45% as compared to a traditional four-phase strategy, and up to 13% as compared to the three-phase strategy without power optimization. 展开更多
关键词 bi-directional cooperation network coding power optimization regenerative strategy max-min optimization
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Oscillation Criteria for Impulsive Hyperbolic Equations of Neutral Type
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作者 ZHU Xian-yang LI Yong-kun LU Ling-hong 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第2期176-184,共9页
Oscillation properties of the solutions of impulsive hyperbolic equations are investigated by the method of differential inequalities.
关键词 OSCILLATION hyperbolic equation IMPULSIVE boundary value problem
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Signal timing optimization model based on dual-ring phase scheme for roundabout 被引量:4
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作者 马万经 谢涵洲 +2 位作者 白玉 赵靖 杨晓光 《Journal of Central South University》 SCIE EI CAS 2013年第2期563-571,共9页
A signal optimization model for roundabout was control concept were used to eliminate the conflict points proposed based on dual-ring scheme and two stop lines for left turns and weaving sections at a roundabout. A cy... A signal optimization model for roundabout was control concept were used to eliminate the conflict points proposed based on dual-ring scheme and two stop lines for left turns and weaving sections at a roundabout. A cycle length minimization problem was considered to generate optimal signal timings for roundabout, and a set of constraints to ensure feasibility and safety of the resulting optimal signal settings were proposed. Extensive experimental analyses in comparison with signalized intersection reveal that the proposed model is quite promising for application in design of roundabout signals, and the minimum cycle length can decrease from 186 s to 79 s while the capacity increases from 8 682 pcu/h to 9 011 pcu/h under high demand scenario. Sensitivity analysis with respect to the system performance show that the lane assignment plan, number of circulatory lanes and left turn ratio are three critical factors which have dominate impacts on performance of signalized roundabout 展开更多
关键词 signalized roundabout dual-ring phase single timing optimization left-turn movement
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Existence and uniqueness for a class of double pyramidal central configurations with a concave pentagonal base
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作者 刘学飞 《Journal of Chongqing University》 CAS 2003年第1期28-30,共3页
Based on some necessary conditions for double pyramidal central configurations with a concave pentagonal base, for any given ratio of masses, the existence and uniqueness of a class of double pyramidal central configu... Based on some necessary conditions for double pyramidal central configurations with a concave pentagonal base, for any given ratio of masses, the existence and uniqueness of a class of double pyramidal central configurations with a concave pentagonal base in 7-body problems are proved and the range of the ratio between radius and half-height is obtained, within which the 7 bodies involved form a central configuration or form uniquely a central configuration. 展开更多
关键词 N-body problem existence and uniqueness concave pentagonal base double pyramidal central configuration
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Absorbing Boundary Conditions for Hyperbolic Systems
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作者 Matthias Ehrhardt 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2010年第3期295-337,共43页
This paper deals with absorbing boundary conditions for hyperbolic systems in one and two space dimensions.We prove the strict well-posedness of the resulting initial boundary value problem in 1D.Afterwards we establi... This paper deals with absorbing boundary conditions for hyperbolic systems in one and two space dimensions.We prove the strict well-posedness of the resulting initial boundary value problem in 1D.Afterwards we establish the GKS-stability of the corresponding Lax-Wendroff-type finite difference scheme.Hereby,we have to extend the classical proofs,since the(discretized) absorbing boundary conditions do not fit the standard form of boundary conditions for hyperbolic systems. 展开更多
关键词 Absorbing boundary conditions hyperbolic system Engquist and Majda approach strict well-posedness GKS-stability.
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A New Lie Algebra and Its Related Liouville Integrable Hierarchies
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作者 王惠 王新赠 +1 位作者 刘国栋 杨记明 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第9期407-411,共5页
A new Lie algebra G and its two types of loop algebras G1 and G2 are constructed. Basing on G1 and G2, two different isospectral problems are designed, furthermore, two Liouville integrable soliton hierarchies are obt... A new Lie algebra G and its two types of loop algebras G1 and G2 are constructed. Basing on G1 and G2, two different isospectral problems are designed, furthermore, two Liouville integrable soliton hierarchies are obtained respectively under the framework of zero curvature equation, which is derived from the compatibility of the isospectral problems expressed by Hirota operators. At the same time, we obtain the Hamiltonian structure of the first hierarchy and the bi-Hamiltonian structure of the second one with the help of the quadratic-form identity. 展开更多
关键词 Lie algebra Liouville integrable hierarchy Hirota operator Quadratic-form identity
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