This work proposes a simple and effective strategy for photon clustering, called regional photon clustering, to accelerate the global illumination updating of dynamic scenes. This method can cluster various numbers of...
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This work proposes a simple and effective strategy for photon clustering, called regional photon clustering, to accelerate the global illumination updating of dynamic scenes. This method can cluster various numbers of photons adaptively. The scenes in adjacent frames are similar, and so most photons have the same moving paths in adjacent frames. Therefore, most photons do not need to be shot again in the next frame. Regional photon clustering employs a quadtree structure to track the trajectory of dynamic objects to reduce the number of re-shot photons. Experimental results show that regional photon clustering reduces the number of re-shot photons, and accelerates the estimation of global illumination in dynamic scenes
This paper presents a new topological localization system for mobile robot navigation based on salient visual regions. These salient regions are obtained by computing the opponencies of color and texture among multi-s...
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ISBN:
(纸本)0769525210
This paper presents a new topological localization system for mobile robot navigation based on salient visual regions. These salient regions are obtained by computing the opponencies of color and texture among multi-scale image spaces. Then they are organized to construct the vertex of topological map using hidden Markov model. So localization problem can be transformed to the evaluation problem of HMM. In our system, the topological map of environment can be created online and the robot locates itself concurrently. Experiments show that higher ratio of vertex recognition, that is localization, is obtained. And our system can guarantee mobile robot navigation safely in unknown environments
This paper presents an interactive data broadcast algorithm for T-DMB/CDMA converged environment. The proposed algorithm improves responsiveness to user requests and resource efficiency by adapting to the various chan...
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This paper presents an interactive data broadcast algorithm for T-DMB/CDMA converged environment. The proposed algorithm improves responsiveness to user requests and resource efficiency by adapting to the various changes of user requests
In this paper, we explore the effect of musical context on audio onset detection using machine learning techniques. We extract the signal intensity and frequency energy of audio as the attributes of input instances fo...
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ISBN:
(纸本)0769527469;9780769527468
In this paper, we explore the effect of musical context on audio onset detection using machine learning techniques. We extract the signal intensity and frequency energy of audio as the attributes of input instances for the machine learning techniques. The audio is synthesized from MIDI files, providing exact information of onset events. We test three state-of-the-art machine learning algorithms, support vector machines (SVM), neural networks (NN), and Naive Bayes (NB) with Ada boosting, for learning and classifying audio onsets. We found that SVMs perform best in general, based on the average of training and 10-fold cross validation errors as the evaluation criterion. We then test the SVM and NN, the two best performing methods, on Bach's Prelude in C major BWV 943, transposed to different keys and time-stretched to various tempi. The error rates ranged from 23.91% (when training set key and tempo equals those of the test set) to 37.22% (when the key is off by four accidentals) and 37.91% (when tempo is 20 beats per minute faster). The results show that audio onset detection performs significantly better when the key and tempo attributes of the test and training sets concur, than when they are different, thus supporting the utility of tempo and key knowledge in designing onset detection systems, or in prescribing confidence statistics to onset detection outcomes
Most digital content and most digital libraries are mainly concerned with artefacts rather than the craft in making them or the skill in using these artefacts. The same concerns manifested in hospital and childcare st...
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Most digital content and most digital libraries are mainly concerned with artefacts rather than the craft in making them or the skill in using these artefacts. The same concerns manifested in hospital and childcare standard operation procedures (SOPs). The motivation for this project is based on several observations. First, information technology and digital libraries are convenient and efficient virtual environments for teaching and learning. In addition, they can be built to the Internet. Second, students in universities expect state-of-the art learning resources from the Web. Third, life-long learning is becoming increasingly important worldwide. Fourth, housewives who intend to be child caregivers will particularly benefit from E-learning materials. Finally, E-learning with interactive videos provides more learner satisfaction than non-interactive and traditional classroom learning. In this paper, an application of online learning in child caregiver training is presented with step-by-step interactive videos that can be used for education of child caregivers. Metadata compatible with the Dublin core are used for recording the individual steps of SOPs. By analyzing and comparing the test scores using t-test, it was found that the system provides a more effective method than the non-interactive or traditional classroom learning (p<0.05). Additionally, analysis of the questionnaires shows that interactive video learning provides more learner satisfaction with Cronbach α measure of 0.766. In conclusion, the system implements a website of childcare SOP and supports an interactive online learning environment for practicing childcare skills. In the future, large-scale investigation and evaluation with more learners will be done for exploring the drawbacks and advantages of interactive learning.
This paper presents an approach to resolve the problem of authoring and interchanging educational material, based on web services. Here we describe the ultimate goal, of reusing and interchanging freely adaptive eleam...
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To meet needs in cell and tissue engineering bioreactors are evolving to allow cells and tissues to be cultured under precisely defined physical and chemical conditions. Many cell-tissue types are now being cultured, ...
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To meet needs in cell and tissue engineering bioreactors are evolving to allow cells and tissues to be cultured under precisely defined physical and chemical conditions. Many cell-tissue types are now being cultured, and considered in this work are chondrocytes, vascular endothelial cells, and smooth muscle cells. The culture processes are dynamic and optimisation requires monitoring of key process variables. The chemical sensing in cell and tissue bioreactors described here has the long term aim of achieving automatic optimal control. Invasive and non-invasive electrochemical and optical systems are described for a wide range of target analytes (gases, ions, metabolites, hormones and proteins), but emphasis is on O 2 , pH, CO 2 and glucose. The sensing is performed with: (a) interrogation via the bioreactor wall; (b) probes placed within the cell culture chamber; (c) analysis within a shunt/sampling chamber. Analysis of culture medium is used for measurement of glucose and for proteins that are markers of cell biosynthetic behaviour. Optical absorbance and scatter of cells and tissues are also investigated for both chemical and structural analysis
In this paper active mode observability is addressed for a class of discrete-time linear systems that may switch in an unknown and unpredictable way among different modes taken from a finite set. The active mode obser...
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ISBN:
(纸本)1424401704;9781424401703
In this paper active mode observability is addressed for a class of discrete-time linear systems that may switch in an unknown and unpredictable way among different modes taken from a finite set. The active mode observation problem consists in determining control sequences (discerning control sequences) that allow to identify the switching sequence on the basis of the observations. The presence of unknown but bounded noises affecting both the system and measurement equations is taken into account. In particular, a general condition is derived that characterizes discerning controls in a finite-horizon setting. Such a result is extended to the infinite-horizon case in order to derive "persistently discerning" control sequences. Numerical examples are reported to clarify the approach
Using OFDM and space-time coding to achieve asynchronous cooperative diversity has been proposed by Mei et. al. and Shin et al, where orthogonal space-time block codes, Alamouti code in particular, were used at relay ...
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Using OFDM and space-time coding to achieve asynchronous cooperative diversity has been proposed by Mei et. al. and Shin et al, where orthogonal space-time block codes, Alamouti code in particular, were used at relay nodes. This proposed space-time coding can not achieve the multipath diversity when the channels from nodes to nodes are frequency selective fading. In this paper, we also consider asynchronous cooperative communications where the channels are assumed to be frequency-selective fading. We design high rate distributed space-frequency codes to achieve both full asynchronous cooperative diversity and multipath diversities.
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