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One of the most significant cost factors in robotics applications is the design and development of real-time robot control software. Control theory helps when linear controllers have to be developed, but it doesn't sufficiently support the generation of non-linear controllers, although in many cases (such as in compliance control), nonlinear control is essential for achieving high performance. This paper discusses how Machine Learning has been applied to the design of (non-)linear controllers. Several alternative function approximators, including Multilayer Perceptrons (MLP), Radial Basis Function Networks (RBFNs), and Fuzzy Controllers are analyzed and compared, leading to the definition of two major families: Open Field Function Approximators and Locally Receptive Field Function Approximators. It is shown that RBFNs and Fuzzy Controllers bear strong similarities, and that both have a symbolic interpretation. This characteristic allows for applying both symbolic and statistic learning algorithms to synthesize the network layout from a set of examples and, possibly, some background knowledge. Three integrated learning algorithms, two of which are original, are described and evaluated on experimental test cases. The first test case is provided by a robot KUKA IR-361 engaged into the peg-into-hole task, whereas the second is represented by a classical prediction task on the Mackey-Glass time series. From the experimental comparison, it appears that both Fuzzy Controllers and RBFNs synthesised from examples are excellent approximators, and that, in practice, they can be even more accurate than MLPs.Institute for Real-Time Computer Systems & Robotics, University of KarlsruheDepartment of Mechanical Engineering, Division PMA, Katholieke Universiteit Leuven 相似文献
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This article describes a framework for the deep and dynamic integration of learning strategies. The framework is based on the idea that each single-strategy learning method is ultimately the result of certain elementary inferences (like deduction, analogy, abduction, generalization, specialization, abstraction, concretion, etc.). Consequently, instead of integrating learning strategies at a macro level, we propose to integrate the different inference types that generate individual learning strategies. The article presents a concept-learning and theory-revision method that was developed in this framework. It allows the system to learn from one or from several (positive and/or negative) examples, and to both generalize and specialize its knowledge base. The method integrates deeply and dynamically different learning strategies, depending on the relationship between the input information and the knowledge base. It also behaves as a single-strategy learning method whenever the applicability conditions of such a method are satisfied. 相似文献
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Learning Decision Lists 总被引:14,自引:21,他引:14
This paper introduces a new representation for Boolean functions, called decision lists, and shows that they are efficiently learnable from examples. More precisely, this result is established for k-;DL – the set of decision lists with conjunctive clauses of size k at each decision. Since k-DL properly includes other well-known techniques for representing Boolean functions such as k-CNF (formulae in conjunctive normal form with at most k literals per clause), k-DNF (formulae in disjunctive normal form with at most k literals per term), and decision trees of depth k, our result strictly increases the set of functions that are known to be polynomially learnable, in the sense of Valiant (1984). Our proof is constructive: we present an algorithm that can efficiently construct an element of k-DL consistent with a given set of examples, if one exists. 相似文献
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李琳 《数字社区&智能家居》2014,(1):115-119
增量式支持向量机学习算法是一种重要的在线学习方法。传统的单增量支持向量机学习算法使用一个数据样本更新支持向量机模型。在增加或删除的数据样本点较多时,这种模型更新模式耗时巨大,具体原因是每个被插入或删除的样本都要进行一次模型参数更新的判断。该文提出一种基于参数规划的多重增量式的支持向量机优化训练算法,使用该训练算法,多重的支持向量机的训练时间大为减少。在合成数据集及真实测试数据集上的实验结果显示,该文提出的方法可以大大降低多重支持向量机训练算法的计算复杂度并提高分类器的精度。 相似文献
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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
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Visual tracking can be treated as a parameter estimation problem that infers target states based on image observations from video sequences. A richer target representation may incur better chances of successful tracking in cluttered and dynamic environments, and thus enhance the robustness. Richer representations can be constructed by either specifying a detailed model of a single cue or combining a set of rough models of multiple cues. Both approaches increase the dimensionality of the state space, which results in a dramatic increase of computation. To investigate the integration of rough models from multiple cues and to explore computationally efficient algorithms, this paper formulates the problem of multiple cue integration and tracking in a probabilistic framework based on a factorized graphical model. Structured variational analysis of such a graphical model factorizes different modalities and suggests a co-inference process among these modalities. Based on the importance sampling technique, a sequential Monte Carlo algorithm is proposed to provide an efficient simulation and approximation of the co-inferencing of multiple cues. This algorithm runs in real-time at around 30 Hz. Our extensive experiments show that the proposed algorithm performs robustly in a large variety of tracking scenarios. The approach presented in this paper has the potential to solve other problems including sensor fusion problems. 相似文献
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刘利 《电脑与微电子技术》2013,(18):17-20
融合相关反馈和流形学习的图像检索方法.既可以解决基于内容图像检索的“语义鸿沟”问题.又可以解决因为用户反馈标记样例较少所导致的较难学习用户语义概念问题。深入研究近年来比较有代表性的方法,包括ARE和MMP,并在具体的系统中比较二者的性能;此外。进一步分析此类方法面临的挑战和实际应用时需迫切解决的问题。 相似文献
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刘晓秋 《电脑与微电子技术》2012,(15):45-47
现在高等学校的学生具有很强的社会的特点,现实性强,在具有众多学生的高等学校内要学生对学习有兴趣,这是一件难事。了解学生,让学生主动学习,靠教育工作者在办公室里是想不出好办法的,让学生参与教学活动,参与教学过程设计,这是提高学习兴趣,主动学习的唯一方法。 相似文献
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Robots have played an important role in the automation of computer aided manufacturing. The classical robot control implementation involves an expensive key step of model-based programming. An intuitive way to reduce this expensive exercise is to replace programming with machine learning of robot actions from demonstration where a (learner) robot learns an action by observing a demonstrator robot performing the same. To achieve this learning from demonstration (LFD) different machine learning techniques such as Artificial Neural Networks (ANN), Genetic Algorithms, Hidden Markov Models, Support Vector Machines, etc. can be used. This piece of work focuses exclusively on ANNs. Since ANNs have many standard architectural variations divided into two basic computational categories namely the recurrent networks and feed-forward networks, representative networks from each have been selected for study, i.e. Feed Forward Multilayer Perceptron (FF) network for feed-forward networks category and Elman (EL), and Nonlinear Autoregressive Exogenous Model (NARX) networks for the recurrent networks category. The main objective of this work is to identify the most suitable neural architecture for application of LFD in learning different robot actions. The sensor and actuator streams of demonstrated action are used as training data for ANN learning. Consequently, the learning capability is measured by comparing the error between demonstrator and corresponding learner streams. To achieve fairness in comparison three steps have been taken. First, Dynamic Time Warping is used to measure the error between demonstrator and learner streams, which gives resilience against translation in time. Second, comparison statistics are drawn between the best, instead of weight-equal, configurations of competing architectures so that learning capability of any architecture is not forced handicap. Third, each configuration's error is calculated as the average of ten trials of all possible learning sequences with random weight initialization so that the error value is independent of a particular sequence of learning or a particular set of initial weights. Six experiments are conducted to get a performance pattern of each architecture. In each experiment, a total of nine different robot actions were tested. Error statistics thus obtained have shown that NARX architecture is most suitable for this learning problem whereas Elman architecture has shown the worst suitability. Interestingly the computationally lesser MLP gives much lower and slightly higher error statistics compared to the computationally superior Elman and NARX neural architectures, respectively. 相似文献
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Unlike the traditional Multiple Kernel Learning (MKL) with the implicit kernels, Multiple Empirical Kernel Learning (MEKL) explicitly maps the original data space into multiple feature spaces via different empirical kernels. MEKL has been demonstrated to bring good classification performance and to be much easier in processing and analyzing the adaptability of kernels for the input space. In this paper, we incorporate the dynamic pairwise constraints into MEKL to propose a novel Multiple Empirical Kernel Learning with dynamic Pairwise Constraints method (MEKLPC). It is known that the pairwise constraint provides the relationship between two samples, which tells whether these samples belong to the same class or not. In the present work, we boost the original pairwise constraints and design the dynamic pairwise constraints which can pay more attention onto the boundary samples and thus to make the decision hyperplane more reasonable and accurate. Thus, the proposed MEKLPC not only inherits the advantages of the MEKL, but also owns multiple folds of prior information. Firstly, MEKLPC gets the side-information and boosts the classification performance significantly in each feature space. Here, the side-information is the dynamic pairwise constraints which are constructed by the samples near the decision boundary, i.e. the boundary samples. Secondly, in each mapped feature space, MEKLPC still measures the empirical risk and generalization risk. Lastly, different feature spaces mapped by multiple empirical kernels can agree to their outputs for the same input sample as much as possible. To the best of our knowledge, it is the first time to introduce the dynamic pairwise constraints into the MEKL framework in the present work. The experiments on a number of real-world data sets demonstrate the feasibility and effectiveness of MEKLPC. 相似文献
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This paper focuses on the creation and presentation of a user-friendly experience for developing computational models of human behavior. Although computational models of human behavior have enjoyed a rich history in cognitive psychology, they have lacked widespread impact, partly due to the technical knowledge and programming required in addition to the complexities of the modeling process. We describe a modeling tool called IBLTool that is a computational implementation of the Instance-based Learning Theory (IBLT). IBLT is a theory that represents how decisions are made from experience in dynamic tasks. The IBLTool makes IBLT usable and understandable to a wider community of cognitive and behavioral scientists. The tool uses graphical user interfaces that take a modeler step-by-step through several IBLT processes and help the modeler derive predictions of human behavior in a particular task. A task would connect and interact with the IBLTool and store the decision-making data while the tool collects statistical data from the execution of a model for the task. We explain the functioning of the IBLTool and demonstrate a concrete example of the design and execution of a model for the Iowa Gambling task. The example is intended to provide a concrete demonstration of the capabilities of the IBLTool. 相似文献
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This paper deals with a classification problem known as learning from label proportions. The provided dataset is composed of unlabeled instances and is divided into disjoint groups. General class information is given within the groups: the proportion of instances of the group that belong to each class.We have developed a method based on the Structural EM strategy that learns Bayesian network classifiers to deal with the exposed problem. Four versions of our proposal are evaluated on synthetic data, and compared with state-of-the-art approaches on real datasets from public repositories. The results obtained show a competitive behavior for the proposed algorithm. 相似文献
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Lyn Dawes 《Computers & Education》1999,33(4):1
The swift introduction of Information and Communications Technology (ICT) into schools is the aim of initiatives involving the teaching profession, parents and pupils, government and commercial interests. Teachers’ attempts to integrate ICT into their classroom practice may be affected by such factors as access to updated technology, appropriate training, and realistic time management. Nevertheless the British governments aim is that all teachers acquire network literacy by the year 2002. Using a linked group of schools, teachers’ opinions and ideas about ICT were gathered as the National Grid for Learning was introduced. Theories of learning as ‘community joining’ were applied in an analysis of the data to create an emerging model of teachers as users of ICT. This model was then used to help formulate the ICT Development Policy of a case study school. On the basis of this empirical evidence, some key factors enabling teachers to work towards network literacy and ‘Adept User’ status are discussed. In conclusion this paper suggests that successful implementation of ICT initiatives generating educationally effective practice is ultimately dependent on the professional development of teachers. 相似文献
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基于模型的强化学习通过学习一个环境模型和基于此模型的策略优化或规划,实现机器人更接近于人类的学习和交互方式.文中简述机器人学习问题的定义,介绍机器人学习中基于模型的强化学习方法,包括主流的模型学习及模型利用的方法.主流的模型学习方法具体介绍前向动力学模型、逆向动力学模型和隐式模型.模型利用的方法具体介绍基于模型的规划、... 相似文献
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《网络安全》教学中学生自主学习能力的培养 总被引:1,自引:0,他引:1
针对《网络安全》课程的特点,为了激发学生的学习兴趣和创新精神,根据教学实践经验提出了《网络安全》教学中培养学生自主学习能力的相关策略。实践证明,在教学过程中加强学生自主学习能力的培养能达到更好的教学效果。 相似文献
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We consider a variant of Gold’s learning paradigm where a learner receives as input n different languages (in the form of one text where all input languages are interleaved). Our goal is to explore the situation when a more “coarse” classification of input languages is possible, whereas more refined classification is not. More specifically, we answer the following question: under which conditions, a learner, being fed n different languages, can produce m grammars covering all input languages, but cannot produce k grammars covering input languages for any k>m. We also consider a variant of this task, where each of the output grammars may not cover more than r input languages. Our main results indicate that the major factor affecting classification capabilities is the difference n−m between the number n of input languages and the number m of output grammars. We also explore the relationship between classification capabilities for smaller and larger groups of input languages. For the variant of our model with the upper bound on the number of languages allowed to be represented by one output grammar, for classes consisting of disjoint languages, we found complete picture of relationship between classification capabilities for different parameters n (the number of input languages), m (number of output grammars), and r (bound on the number of languages represented by each output grammar). This picture includes a combinatorial characterization of classification capabilities for the parameters n,m,r of certain types. 相似文献
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A. Famili 《Journal of Intelligent and Robotic Systems》1990,3(2):117-130
This paper presents an overview of learning and decision-making in intelligent manufacturing systems. Machine learning techniques applicable to design and manufacturing are reviewed. Issues related to the role of learning in manufacturing decision-making and two related examples are discussed. The architecture, algorithm and implementation of the first prototype of IMAFO, an intelligent supervisory system, which has learning capabilities, are explained. 相似文献
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随着Moodle网络教学平台在国内的推广和普及,Moodlep平台在教学中的作用日益凸显。针对目前Moodle网络课程重视教学内容的呈现与讲解,轻学习环境与学习活动的设计等普遍存在的问题。深入研究Moodle平台的各功能模块,在Moodle中设计有效的学习活动,交互性的学习活动组织,以期更好地使用Moodle平台。 相似文献