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101.
以适应性学习为基础,提出了在自适应性学习(Adaptive Learning)中如何将案例教学(Case-based Learning)融入其中,在学习中如何对学习进行评价,并根据评价为学习者提供与其相适应的案例,让学习者在情境中学习,使得学习更加高效可行。 相似文献
102.
网络教学系统已经逐渐成为新世纪教育教学发展的一种趋势,各高校在今后的教育教学中会更深入、广泛地应用。本文以我院网络教学平台为例,对网络教学平台的应用及管理情况进行探讨。 相似文献
103.
Jian Liu Lockhart T.E. Jones M. Martin T. 《Automation Science and Engineering, IEEE Transactions on》2008,5(4):696-702
A clear association has been demonstrated between gait stability and falls in the elderly. Integration of wearable computing and human dynamic stability measures into home automation systems may help differentiate fall-prone individuals in a residential environment. The objective of the current study was to evaluate the capability of a pair of electronic textile (e-textile) pants system to assess local dynamic stability and to differentiate motion-impaired elderly from their healthy counterparts. A pair of e-textile pants comprised of numerous e-TAGs at locations corresponding to lower extremity joints was developed to collect acceleration, angular velocity and piezoelectric data. Four motion-impaired elderly together with nine healthy individuals (both young and old) participated in treadmill walking with a motion capture system simultaneously collecting kinematic data. Local dynamic stability, characterized by maximum Lyapunov exponent, was computed based on vertical acceleration and angular velocity at lower extremity joints for the measurements from both e-textile and motion capture systems. Results indicated that the motion-impaired elderly had significantly higher maximum Lyapunov exponents (computed from vertical acceleration data) than healthy individuals at the right ankle and hip joints. In addition, maximum Lyapunov exponents assessed by the motion capture system were found to be significantly higher than those assessed by the e-textile system. Despite the difference between these measurement techniques, attaching accelerometers at the ankle and hip joints was shown to be an effective sensor configuration. It was concluded that the e-textile pants system, via dynamic stability assessment, has the potential to identify motion-impaired elderly. 相似文献
104.
我试图通过解读修辞学的发展历程,探究符号学发展的必然性,由本不存在修辞,到需要修辞,再到修辞的消亡的逻辑关系,联想到设计符号学的发展历程竟与其如此惊人的相似,由仅追求原始功能,到添加装饰满足非本质的需求,继而又摒弃装饰成分,聚焦其本质所在的现代设计,就像我在文章开头说的乙杂邢薜姆绞奖硐治尴蘧褪敲烙是象征的精髓一样,以最简洁的形式传达了最准确的信息,是设计符号学的核心所在。 相似文献
105.
106.
利用计算机进行设计各种字形修饰效果一直是计算机图形学的重要内容之一.本文给出了在轮廓字表面上构造网格点,基于这些网格点进行Delaunay三角剖分,并转换为3-4网格,最后在网格上实现编织带修饰效果的具体实现方法.其中3-4网格由良构的四边形单元和少量辅助三角形单元构成,在其上实现了较好的编织带修饰的效果. 相似文献
107.
Yan R Zhang J Yang J Hauptmann AG 《IEEE transactions on pattern analysis and machine intelligence》2006,28(4):578-593
To deal with the problem of insufficient labeled data in video object classification, one solution is to utilize additional pairwise constraints that indicate the relationship between two examples, i.e., whether these examples belong to the same class or not. In this paper, we propose a discriminative learning approach which can incorporate pairwise constraints into a conventional margin-based learning framework. Different from previous work that usually attempts to learn better distance metrics or estimate the underlying data distribution, the proposed approach can directly model the decision boundary and, thus, require fewer model assumptions. Moreover, the proposed approach can handle both labeled data and pairwise constraints in a unified framework. In this work, we investigate two families of pairwise loss functions, namely, convex and nonconvex pairwise loss functions, and then derive three pairwise learning algorithms by plugging in the hinge loss and the logistic loss functions. The proposed learning algorithms were evaluated using a people identification task on two surveillance video data sets. The experiments demonstrated that the proposed pairwise learning algorithms considerably outperform the baseline classifiers using only labeled data and two other pairwise learning algorithms with the same amount of pairwise constraints. 相似文献
108.
Zhijun Chao Yugeng Xi 《Automatic Control, IEEE Transactions on》2001,46(11):1794-1797
In this paper, the control structures and control technologies in decentralized discrete event control system are investigated. It shows that if the control structures on two local systems are standard and locally definable, so is the product control structure. Furthermore, a control technology associated with the product control structure is also given 相似文献
109.
110.
介绍了世界内陆核电发展概况,分析了中国内陆核电发展的必要性,从水资源安全、核辐射安全和公众环境安全角度分别论述了AP1000核电技术对内陆核电的适应性。 相似文献