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111.
Special education and mathematics education are becoming increasingly intertwined in inclusive classrooms. However, research and practice in these two fields are not always aligned. We discuss, in the context of extant research on pedagogical theory, concepts of access, and the findings of an exploratory study, how these two education sub-fields view teacher expertise. Teacher educators (from math and special education) were asked to rank the importance of different types of expertise for effectively posing purposeful mathematical questions. The groups differed significantly in their rankings of the importance of knowing individual students and general teaching experience. There were also notable differences between the groups’ rankings of the importance of knowing the needs of students with disabilities and mathematical content knowledge. The possible reasons for this are discussed, along with suggestions for improving professional collaboration. 相似文献
112.
梁方程时间依赖全局吸引子的存在性 总被引:1,自引:1,他引:0
研究了梁方程时间依赖吸引子的存在性,在非线性项f满足临界增长条件时,基于时间依赖全局吸引子的存在性定理,应用先验估计和算子分解方法验证了系数参数与时间t有关时,梁方程对应的过程族{U(t,τ)}的渐近紧性,从而得到梁方程时间依赖全局吸引子的存在性及正则性. 相似文献
113.
个性化试题推荐、试题难度预测、学习者建模等教育数据挖掘任务需要使用到学生作答数据资源及试题知识点标注,现阶段的试题数据都是由人工标注知识点。因此,利用机器学习方法自动标注试题知识点是一项迫切的需求。针对海量试题资源情况下的试题知识点自动标注问题,本文提出了一种基于集成学习的试题多知识点标注方法。首先,形式化定义了试题知识点标注问题,并借助教材目录和领域知识构建知识点的知识图谱作为类别标签。其次,采用基于集成学习的方法训练多个支持向量机作为基分类器,筛选出表现优异的基分类器进行集成,构建出试题多知识点标注模型。最后,以某在线教育平台数据库中的高中数学试题为实验数据集,应用所提方法预测试题考察的知识点,取得了较好的效果。 相似文献
114.
From the fundamental parts of PLS‐DA, Fisher's canonical discriminant analysis (FCDA) and Powered PLS (PPLS), we develop the concept of powered PLS for classification problems (PPLS‐DA). By taking advantage of a sequence of data reducing linear transformations (consistent with the computation of ordinary PLS‐DA components), PPLS‐DA computes each component from the transformed data by maximization of a parameterized Rayleigh quotient associated with FCDA. Models found by the powered PLS methodology can contribute to reveal the relevance of particular predictors and often requires fewer and simpler components than their ordinary PLS counterparts. From the possibility of imposing restrictions on the powers available for optimization we obtain an explorative approach to predictive modeling not available to the traditional PLS methods. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
115.
Eusthathios Giannakoulias Theodossios Zachariades 《The Journal of Mathematical Behavior》2010,29(3):160-168
This study investigates teachers’ argumentation aiming to convince students about the invalidity of their mathematical claims in the context of calculus. 18 secondary school mathematics teachers were given three hypothetical scenarios of a student's proof that included an invalid algebraic claim. The teachers were asked to identify possible mistakes and explain how they would refute the student's invalid claims. Two of them were also interviewed. The data were analysed in terms of the content and structure of argumentation and the types of counterexamples the teachers generated. The findings show that teachers used two main approaches to refute students’ invalid claims, the use of theory and the use of counterexamples. The role of these approaches in the argumentation process was analysed by Toulmin's model and three types of reasoning emerged that indicate the structure of argumentation in the case of refutation. Concerning the counterexamples, the study shows that few teachers use them in their argumentation and in general they underestimate their value as a proof method. 相似文献
116.
将范例推理技术应用于问卷设计知识重用过程中,提出了基于范例推理的问卷设计知识重用系统的应用框架,研究了问卷设计CBR系统中的一些关键技术:范例的表示、范例组织、范例检索算法、范例修正优化和重用、范例学习等.范例检索采用KNN法与遗传禁忌算法相结合的混合检索机制,通过建立GA适应度函数模型以及选择、禁忌交叉、禁忌变异算子等自动确定权重.我们组织和建立了初步的范例知识库,进行了相关实验.结果表明,融合遗传算法的范例检索方法可较大程度上缩短设计时间、提高问卷设计效率和质量,并有效地支持问卷设计的知识重用和知识管理创新. 相似文献
117.
一种改进的图像快速去雾新方法 总被引:3,自引:0,他引:3
为提高雾霭天降质图像的清晰度和色彩保真度,基于暗原色先验提出了一种改进的图像快速去雾方法.针对原方法运算时间过长的问题,在保证去雾效果的前提下,利用快速双边滤波方法代替软件抠图修复透过率图,大幅度地降低了计算量和复杂度,处理时间仅为原方法的5%,满足了一般工程上的实时性要求.针对去雾处理后的图像亮度降低、颜色较实际场景偏暗的问题,提出了一种简单有效的图像对比度和亮度增强的方法,自适应地增强了图像的亮度,并对局部由于雾浓度过高而造成不清晰的区域,进行了对比度修正.结果表明,该方法能够快速有效地复原出雾天场景的对比度和真实色彩,在一定程度上保证了户外成像系统在恶劣天气下工作的稳定性和可靠性. 相似文献
118.
T. Stevens X. Liu Z. Aguirre-Munoz 《International Journal of Mathematical Education in Science & Technology》2013,44(7):984-995
In this paper, we explore a novel approach for assessing the impact of a professional development programme on classroom practice of in-service middle school mathematics teachers. The particular focus of this study is the assessment of the impact on teachers’ employment of strategies used in the classroom to foster the mathematical habits of mind and mathematical self-efficacy of their students. We describe the creation and testing of a student survey designed to assess teacher classroom practice based primarily on students’ ratings of teacher practices. 相似文献
119.
We present a method of imposing constraints in extracting formal concepts (equivalently, closed itemsets or fixpoints of Galois connections) from a binary relation. The constraints are represented by closure operators and their purpose is to mimic background knowledge a user may have of the data. The idea is to consider and extract only these itemsets that are compatible with the background knowledge. As a result, the method extracts less clusters, those that are interesting from the user point of view, in a shorter time. The method makes it also possible to extract minimal bases of attribute dependencies in the input data that are compatible with the background knowledge. We provide examples of several particular types of constraints including those that appeared in the literature in the past and present algorithms to compute the constrained formal concepts and attribute implications. 相似文献
120.
Wenjiang J. Fu 《Journal of computational and graphical statistics》2013,22(3):397-416
Abstract Bridge regression, a special family of penalized regressions of a penalty function Σ|βj|γ with γ ≤ 1, considered. A general approach to solve for the bridge estimator is developed. A new algorithm for the lasso (γ = 1) is obtained by studying the structure of the bridge estimators. The shrinkage parameter γ and the tuning parameter λ are selected via generalized cross-validation (GCV). Comparison between the bridge model (γ ≤ 1) and several other shrinkage models, namely the ordinary least squares regression (λ = 0), the lasso (γ = 1) and ridge regression (γ = 2), is made through a simulation study. It is shown that the bridge regression performs well compared to the lasso and ridge regression. These methods are demonstrated through an analysis of a prostate cancer data. Some computational advantages and limitations are discussed. 相似文献