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Impurity-induced local modes in one-dimensional dusty plasma chains
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作者 任永超 王欣上 王晓钢 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期321-326,共6页
The effects of impurity on eigenmodes in one-dimensional dusty plasma lattices are studied. It is found that local modes can be excited besides lattice waves, due to the existence of an impurity particle. The dispersi... The effects of impurity on eigenmodes in one-dimensional dusty plasma lattices are studied. It is found that local modes can be excited besides lattice waves, due to the existence of an impurity particle. The dispersion relations of the modes are derived accordingly. Properties of the lattice and local modes are also analyzed and discussed, particularly for their symmetric features and conditions of the mode excitation. 展开更多
关键词 IMPURITY local mode dusty plasma
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Solitons and intrinsic localized modes in a one-dimensional antiferromagnetic chain 被引量:3
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作者 李德俊 米贤武 +1 位作者 邓科 唐翌 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第1期39-44,共6页
By use of the Hartree approximation and the method of multiple scales, we investigate quantum solitons and intrinsic localized modes in a one-dimensional antiferromagnetic chain. It is shown that there exist solitons ... By use of the Hartree approximation and the method of multiple scales, we investigate quantum solitons and intrinsic localized modes in a one-dimensional antiferromagnetic chain. It is shown that there exist solitons of two different quantum frequency bands: i.e., magnetic optical solitons and acoustic solitons. At the boundary of the Brillouin zone, these solitons becornc quantum intrinsic localized modes: their quantum eigenfrequencics are below the bottom of the harmonic optical frequency band and above the top of the harmonic acoustic frequency band. 展开更多
关键词 antiferromagnetic chain Hartree approximation quantum soliton quantum intrinsic localized mode
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Research on mode localization of reticulated shell structures 被引量:4
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作者 Yan Weiming Wang Zhuo He Haoxiang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2011年第1期75-84,共10页
Reticulated shell structures (RSSs) are characterized as cyclically periodic structures. Mistuning of RSSs will induce structural mode localization. Mode localization has the following two features: some modal vect... Reticulated shell structures (RSSs) are characterized as cyclically periodic structures. Mistuning of RSSs will induce structural mode localization. Mode localization has the following two features: some modal vectors of the structure change remarkably when the values of its physical parameters (mass or stiffness) have a slight change; and the vibration of some modes is mainly restricted in some local areas of the structure. In this paper, two quantitative assessment indexes are introduced that correspond to these two features. The first feature is studied through a numerical example of a RSS, and its induced causes are analyzed by using the perturbation theory. The analysis showed that internally, mode localization is closely related to structural frequencies and externally, slight changes of the physical parameters of the structure cause instability to the RSS. A scaled model experiment to examine mode localization was carried out on a Kiewit single-layer spherical RSS, and both features of mode localization are studied. Eight tests that measured the changes of the physical parameters were carried out in the experiment. Since many modes make their contribution in structural dynamic response, six strong vibration modes were tested at random in the experimental analysis. The change and localization of the six modes are analyzed for each test. The results show that slight changes to the physical parameters are likely to induce remarkable changes and localization of some modal vectors in the RSSs. 展开更多
关键词 reticulated shell structure mistuning mode localization perturbation theory seismic performance analysis damage identification
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Bright and dark small amplitude nonlinear localized modes in a quantum one-dimensional Klein-Gordon chain 被引量:1
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作者 刘洋 唐翌 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第10期3841-3846,共6页
By means of the Glauber's coherent state method combined with multiple-scale method, this paper investigates the localized modes in a quantum one-dimensional Klein-Gordon chain and finds that the equation of motion o... By means of the Glauber's coherent state method combined with multiple-scale method, this paper investigates the localized modes in a quantum one-dimensional Klein-Gordon chain and finds that the equation of motion of annihilation operator is reduced to the nonlinear Schroedinger equation. Interestingly, the model can support both bright and dark small amplitude travelling and non-travelling nonlinear localized modes in different parameter spaces. 展开更多
关键词 nonlinear localized modes coherent state Klein-Gordon chain
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Quantum Solitons and Localized Modes in a One-Dimensional Lattice Chain with Nonlinear Substrate Potential 被引量:1
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作者 LI De-Jun MI Xian-Wu +1 位作者 DENG Ke TANG Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期869-872,共4页
In the classical lattice theory, solitons and localized modes can exist in many one-dimensional nonlinear lattice chains, however, in the quantum lattice theory, whether quantum solitons and localized modes can exist ... In the classical lattice theory, solitons and localized modes can exist in many one-dimensional nonlinear lattice chains, however, in the quantum lattice theory, whether quantum solitons and localized modes can exist or not in the one-dimensional lattice chains is an interesting problem. By using the number state method and the Hartree approximation combined with the method of multiple scales, we investigate quantum solirons and localized modes in a one-dimensional lattice chain with the nonlinear substrate potential. It is shown that quantum solitons do exist in this nonlinear lattice chain, and at the boundary of the phonon Brillouin zone, quantum solitons become quantum localized modes, phonons are pinned to the lattice of the vicinity at the central position j = j0. 展开更多
关键词 number state method Hartree approximation quantum envelope soliton quantum localized mode
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Multi-mode process monitoring based on a novel weighted local standardization strategy and support vector data description 被引量:7
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作者 赵付洲 宋冰 侍洪波 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第11期2896-2905,共10页
There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because the... There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because their presumptions are that sampled-data should obey the single Gaussian distribution or non-Gaussian distribution. In order to solve these problems, a novel weighted local standardization(WLS) strategy is proposed to standardize the multimodal data, which can eliminate the multi-mode characteristics of the collected data, and normalize them into unimodal data distribution. After detailed analysis of the raised data preprocessing strategy, a new algorithm using WLS strategy with support vector data description(SVDD) is put forward to apply for multi-mode monitoring process. Unlike the strategy of building multiple local models, the developed method only contains a model without the prior knowledge of multi-mode process. To demonstrate the proposed method's validity, it is applied to a numerical example and a Tennessee Eastman(TE) process. Finally, the simulation results show that the WLS strategy is very effective to standardize multimodal data, and the WLS-SVDD monitoring method has great advantages over the traditional SVDD and PCA combined with a local standardization strategy(LNS-PCA) in multi-mode process monitoring. 展开更多
关键词 multiple operating modes weighted local standardization support vector data description multi-mode monitoring
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Intrinsic Localized Modes in an Order-parameter-preserving Antiferromagnet
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作者 Wuming LIU+ Shaoyun FU Benlian ZHOU, International Centre for Materials Physics, Institute of Metal Research, Academia Sinica, Shenyang, 110015, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1993年第2期148-152,共5页
Intrinsic localized modes in an order-parameter-preserving antiferromagnet are investigated with employing the Dyson-Maleev transformation and the coherent-state ansatz. These modes which be- low the magnon frequency ... Intrinsic localized modes in an order-parameter-preserving antiferromagnet are investigated with employing the Dyson-Maleev transformation and the coherent-state ansatz. These modes which be- low the magnon frequency band correspond to a local large-angle, low-frequency precessional mo- tion of spins, quantum states of which are characterized by the indefiniteness of the number of rele- vant magnons. 展开更多
关键词 intrinsic localized mode ANTIFERROMAGNET MAGNON
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Estimation of tungsten production from the upper divertor in EAST during edge localized modes
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作者 Jing Ou Nong Xiang +3 位作者 Zong-Zheng Men Ling Zhang Ji-Chan Xu Wei Gao 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期223-230,共8页
During edge localized modes(ELMs), the sheath evolution in front of the Experimental Advanced Superconducting Tokamak(EAST) upper divertor is studied to estimate the sputtered tungsten(W) atoms from the divertor targe... During edge localized modes(ELMs), the sheath evolution in front of the Experimental Advanced Superconducting Tokamak(EAST) upper divertor is studied to estimate the sputtered tungsten(W) atoms from the divertor target. A large potential drop across the sheath is formed during ELMs by compared with inter-ELMs, and the maximum of sheath potential drop can exceed one thousand of e V in current EAST operation. Due to the enhancement of the sheath potential drop during ELMs, the W physical sputtering yield from the deuterium(D) ions and the impurity ions on the upper divertor target is found to be significant. It is established that the sputtered W yield during ELMs is at least higher by an order of magnitude than inter-ELMs, and D ions and carbon(C) ions are the main ions governing the W production for the current H-mode with ELMs discharges. With increase in the pedestal electron temperature, the maximum of the D and C ion impact energy during ELMs shows a nearly linear increase, and the D ions have sufficient impact energy to cause the strong W physical sputtering. As a consequence, the D ions may dominate the sputtered W flux from the divertor target when the C concentration is controlled less than one percent for the higher heating power H-mode with ELM discharges in near future. 展开更多
关键词 SHEATH edge localized modes impact energy
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Relationship between the Local Vibration Mode Characteristics and the Charge State of Carbon Acceptor in GaAs
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作者 杨瑞霞 李光平 +1 位作者 王琴 何秀坤 《Rare Metals》 SCIE EI CAS CSCD 1992年第3期207-211,共5页
The local vibration mode(LVM)of carbon acceptor in GaAs is studied by measuring directly the change in LVM absorption with a NIC-170 SX FT-IR spectrometer.The change in the charge state of carbon acceptor and the temp... The local vibration mode(LVM)of carbon acceptor in GaAs is studied by measuring directly the change in LVM absorption with a NIC-170 SX FT-IR spectrometer.The change in the charge state of carbon acceptor and the temperature dependence of the LVM absorption were investigated also.The contents of the impurities other than carbon were estimated by secondary ion mass spectrometry.It is observed that the frequency,the spectral form and the integrated absorption of the LVM are not affected by the change in charge state of car- bon acceptor. 展开更多
关键词 local vibration mode GAAS Charge state Carbon acceptor ABSORPTION
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Sideband Absorption and its Effects on Temperature Dependence of Local Vibrational Mode Main Absorption Band for Carbon Acceptor in Gallium Arsenide
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作者 杨瑞霞 李光平 《Rare Metals》 SCIE EI CAS CSCD 1999年第4期305-310,共6页
The local vibrational mode (LVM) optical absorption band of carbon acceptor was investigated carefully. Because of the appearance of a sideband on the low energy side of the LVM main absorption band, it is found that ... The local vibrational mode (LVM) optical absorption band of carbon acceptor was investigated carefully. Because of the appearance of a sideband on the low energy side of the LVM main absorption band, it is found that the measured value of the integrated area for the main absorption band is sensitive to the choice of integration baseline wavenumber range (BWR). This is the main cause that the experimental results from different investigators show a wide spread for the temperature dependence of the integrated area. The origin of the sideband is also discussed. 展开更多
关键词 carbon acceptor local vibrational mode excited state
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A GEOMETRIC THEORY IN INVESTIGATION ON MODE LOCALIZATION AND FREQUENCY LOCI VEERING PHENOMENA
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作者 Liu, JK Zhao, LC Fang, T 《Acta Mechanica Solida Sinica》 SCIE EI 1995年第4期349-355,共7页
According to the mapping theory in complex plane, the geometric features of eigen frequency loci of systems undergoing free vibrations are investigated. It is concluded that the phenomena of curve coalescence and veer... According to the mapping theory in complex plane, the geometric features of eigen frequency loci of systems undergoing free vibrations are investigated. It is concluded that the phenomena of curve coalescence and veering can be described in a unified manner from the singularities of mapping from the complex parameter plane onto the complex frequency plane. The formation of a branch point in the parameter Space is the foundation of explaining localization and veering phenomena. By the use of condensation to reduce the dimension of a system, the scope of application of the geometric theory is widely expanded. The theory is applied to examples to verify the validity of the proposed approach. The present work is an improvement and extension of recent work by M. S. Traintafyllou et al.. 展开更多
关键词 complex plane mapping mode localization frequency loci veering CONDENSATION
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Study on local mode vibrations of molecular vibrational excitation states in CH_4,SiH_4 and GeH_4 with quasiclassical trajectory method
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作者 杨忠志 李慎敏 唐敖庆 《Science China Chemistry》 SCIE EI CAS 1995年第8期912-919,共8页
By using the quasiclassical trajectory method,changes of normal and local mode vibrational excitation energies with time are investigated for XH_4 (X=C,Si,Ge) molecules.The results demonstrate that in a CH_4 molecule ... By using the quasiclassical trajectory method,changes of normal and local mode vibrational excitation energies with time are investigated for XH_4 (X=C,Si,Ge) molecules.The results demonstrate that in a CH_4 molecule the coupling between C—H stretching vibration and H—C—H bending vibration is relative- ly large so that the energy transfer is fast;while in SiH_4 or GeH_4 molecules this coupling is relatively small and thus an obvious energy relaxation is observed.This implies that there exists approximate local mode vibrations for certain vibrational excitation states. 展开更多
关键词 quasiclassical TRAJECTORY METHOD local mode NORMAL mode
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Anomalous intensities of local mode vibrational absorption of germane and a new theoretical explanation
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作者 廖结楼 朱清时 《Science China Chemistry》 SCIE EI CAS 1998年第2期202-206,共5页
The (4000), (3100) and (5000) local mode vibrational bands of germane were recorded with high resolution spectroscopy. The anomalous relative intensities of these bands were found and explained with a bond bond coupli... The (4000), (3100) and (5000) local mode vibrational bands of germane were recorded with high resolution spectroscopy. The anomalous relative intensities of these bands were found and explained with a bond bond coupling dipole moment model. The calculated results, which were also compared with those from the former theoretical model, agree well with the experimental data. 展开更多
关键词 local mode VIBRATIONAL intensity high resolution spectroscopy BOND BOND coupling dipole model.
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Analysis on the Development Trend of Contemporary Local Governance Mode from the perspective of Economic Policy and Environmental Capacity Optimization
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作者 Qimei Wang 《International Journal of Technology Management》 2016年第9期50-52,共3页
As the basic level of national governance, local governance is deeply influenced by administrative tradition, political system and economic development level of a country. With more than thirty years of reform and ope... As the basic level of national governance, local governance is deeply influenced by administrative tradition, political system and economic development level of a country. With more than thirty years of reform and opening up, the pattern of local governance has become diversified. The diversity of governance model cannot be managed in the same way, however, it cannot affect the government’s ability to play the initiative role of governance. We need to innovate and improve the existing local governance models. 展开更多
关键词 Development Trend Economic Policy Environmental Capacity Optimization Contemporary local Governance mode.
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Conditional Diagnosability of the Locally Twisted Cubes under the PMC Model 被引量:4
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作者 Ruitao Feng Genqing Bian Xinke Wang 《Communications and Network》 2011年第4期220-224,共5页
In a multiprocessor systems, it is important to local and to replace the faulty processors to maintain systempsilas high reliability. The fault diagnosis, which is the process of identifying fault processors in a mult... In a multiprocessor systems, it is important to local and to replace the faulty processors to maintain systempsilas high reliability. The fault diagnosis, which is the process of identifying fault processors in a multiprocessor system through testing. The conditional diagnosis requires that for each processor u in a system, all the processors that are directly connected to u do not fail at the same time. In this paper, we study the conditional diagnosability of the n-dimensional locally twisted cubes. After showing some properties of the locally twisted cubes, we prove that it under the PMC model is 4n – 7 for n ≥ 5. 展开更多
关键词 localLY TWISTED CUBES DIAGNOSABILITY CONDITIONAL DIAGNOSABILITY PMC mode
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Mode Localization in Modular Trussed Structures and Subjected to Slightly Disordered Loading
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作者 Reyolando Manoel Lopes Rebello da Fonseca Brasil 《材料科学与工程(中英文B版)》 2013年第3期177-182,共6页
关键词 桁架结构 模块化 本地化 装载模式 振动模式 几何刚度矩阵 光耦合 结构组成
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Discrete modulational instability and bright localized spin wave modes in easy-axis weak ferromagnetic spin chains involving the next-nearest-neighbor coupling
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作者 Jiayu Xie Zhihao Deng +1 位作者 Xia Chang Bing Tang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期449-458,共10页
We report a theoretical work on the properties of modulational instability and bright type nonlinear localized modes in one-dimensional easy-axis weak ferromagnetic spin lattices involving next-nearest-neighbor coupli... We report a theoretical work on the properties of modulational instability and bright type nonlinear localized modes in one-dimensional easy-axis weak ferromagnetic spin lattices involving next-nearest-neighbor couplings.With a linear stability analysis, we calculate the growth rates of the modulational instability, and plot the instability regions.When the strength of the next-nearest-neighbor coupling is large enough, two new asymmetric modulational instability regions appear near the boundary of the first Brillouin zone.Furthermore, analytical forms of the bright nonlinear localized modes are constructed by means of a quasi-discreteness approach.The influence of the next-nearest-neighbor coupling on the Brillouin zone center mode and boundary mode are discussed.In particular, we discover a reversal phenomenon of the propagation direction of the Brillouin zone boundary mode. 展开更多
关键词 modulational instability analysis intrinsic localIZED SPIN-WAVE modeS weak FERROMAGNETS NEXT-NEAREST-NEIGHBOR couplings
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基于Local-BGM法的冷涡暴雨集合预报试验及评估检验
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作者 张海鹏 智协飞 +3 位作者 李昊 黎振宇 张志强 黄晶 《气象科学》 北大核心 2023年第1期36-45,共10页
基于传统增长模繁殖法(Breeding Growing Mode,BGM)和局地增长模繁殖法(Local Breeding Growing Mode,Local-BGM)生成初始扰动成员,对一次冷涡暴雨过程进行集合预报试验,从多方面比较两种方案的预报效果,并且在邻域概率法(Neighborhood ... 基于传统增长模繁殖法(Breeding Growing Mode,BGM)和局地增长模繁殖法(Local Breeding Growing Mode,Local-BGM)生成初始扰动成员,对一次冷涡暴雨过程进行集合预报试验,从多方面比较两种方案的预报效果,并且在邻域概率法(Neighborhood Probability,NP)中引入时间邻域,评估概率预报结果。结果表明,引入局地化思想的Local-BGM方案能够生成比传统BGM方案更合理的初始扰动,具有很明显的局地特征。对于扰动变量的预报,Local-BGM方案在均方根误差和离散度等方面均表现更好,同时能够提高各量级降水的预报技巧。邻域集合概率法能够综合各个集合成员预报的降水信息得到优于集合平均的概率预报,分数技巧评分更高。并且在考虑时间不确定性后,无论是控制预报、集合平均还是邻域集合概率法,分数技巧评分均有很大改善,并且降水阈值越大改善效果越明显,能够为极端强降水天气提供较为客观的概率预报信息。 展开更多
关键词 集合预报 局地增长模繁殖法 降水预报 邻域概率法 分数技巧评分
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斜拉桥面内振动的理论建模与特征值分析
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作者 王连华 谢学鑫 +1 位作者 彭剑 张晓宇 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第7期39-49,共11页
本文建立了斜拉桥的精细化面内动力学模型,并开展了相应的自振特性分析.首先利用Hamilton变分原理推导了斜拉桥的运动方程,利用边界条件确定了斜拉桥线性化模型的频率方程.然后以双塔三跨斜拉桥为例开展数值分析,通过对比有限元结果验... 本文建立了斜拉桥的精细化面内动力学模型,并开展了相应的自振特性分析.首先利用Hamilton变分原理推导了斜拉桥的运动方程,利用边界条件确定了斜拉桥线性化模型的频率方程.然后以双塔三跨斜拉桥为例开展数值分析,通过对比有限元结果验证了数值方法的正确性.同时引入局部化因子定量说明斜拉桥固有模态的特性.最后讨论了不同结构参数、索梁相互作用和结构体系对斜拉桥自振特性的影响.结果表明当系统的固有频率接近纯索频率时,斜拉桥的固有模态将呈现局部特性.同时索梁相互作用明显影响低阶非局部模态,相反可以忽略对高阶固有频率的影响. 展开更多
关键词 斜拉桥 索梁相互作用 Hamilton变分原理 固有频率 局部模态
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师范专业认证背景下地方综合性高校地理科学专业人才培养模式构建──以宁波大学为例 被引量:2
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作者 曹罗丹 王一帆 李加林 《宁波教育学院学报》 2024年第1期90-94,共5页
师范专业认证是衡量高校师范素质教育的一个重要指标,对指导地方综合性大学教师教育专业的人才培养具有重要意义。立足师范认证的核心理念,结合宁波大学地理科学(师范)的专业现状,提出“1234”新课程体系人才培养模式。并在此基础上,对... 师范专业认证是衡量高校师范素质教育的一个重要指标,对指导地方综合性大学教师教育专业的人才培养具有重要意义。立足师范认证的核心理念,结合宁波大学地理科学(师范)的专业现状,提出“1234”新课程体系人才培养模式。并在此基础上,对通识课程、专业课程、教师教育课程、综合实践课程等教育平台的建设和改革进行了探讨:以区域综合为特点,打造通识课程平台;以学生兴趣为导向,搭造专业课程平台;以师范性为中心,打造教师教育课程中心;以实践教学资源为依托,搭建综合实践课程平台。通过构建一套完整的评价与持续改进体系,以期为师范认证背景下的专业建设和人才培养提供参考。 展开更多
关键词 师范专业认证 地理科学 地方高校 人才培养模式
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