In this paper we use mutual information to study the distribution in time and frequency of information relevant for phonetic classification. A large database of hand-labeled fluent speech is used to (a) compute the mu...
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In this paper we use mutual information to study the distribution in time and frequency of information relevant for phonetic classification. A large database of hand-labeled fluent speech is used to (a) compute the mutual information between phoneme labels and a point of logarithmic energy in the time-frequency plane and (b) compute the joint mutual information between phoneme labels and two points of logarithmic energy in the time-frequency plane.
We explore the intricacies of the duality of data hiding and data compression to help develop optimal data hiding techniques for images, that can reasonably resist lossy compression. The problem of efficient data hidi...
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We explore the intricacies of the duality of data hiding and data compression to help develop optimal data hiding techniques for images, that can reasonably resist lossy compression. The problem of efficient data hiding is split into two sub-problems-one of maximizing the resource-which is the permitted distortion of images, and the other of efficient use of the resource by means of sophisticated signaling techniques. Various options for the solutions of the former problem are proposed and their advantages and disadvantages explored. An optimal data hiding scheme making "good" use of the resource, using sophisticated signaling techniques is proposed.
Teletraffic modelling of users is crucial for cellular system layout and planning, and to evaluate tradeoffs in system design issues. In order to be useful, the model should capture mobility under the most generalized...
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Teletraffic modelling of users is crucial for cellular system layout and planning, and to evaluate tradeoffs in system design issues. In order to be useful, the model should capture mobility under the most generalized conditions. We develop models that incorporate general mobility patterns that are induced by the cell topography (e.g., road layout, street orientation, density of intersections). In particular, we study the effect of the different mobility patterns on the handoff probability. The mobility patterns are induced by common terrains such as random, Manhattan, circular and highway. The results suggest that we may be able to estimate the handoff probabilities from a knowledge of the cell terrain, the mobile trajectory, and the vehicular movements in a cellular network, and thus may serve as a useful guide for cellular network engineering.
This colloquium is organized in honor of Dr Harlan *** (1919-1996), and is intended to celebrate his legacy in the theory and practice of software engineering.
ISBN:
(纸本)9781581130744
This colloquium is organized in honor of Dr Harlan *** (1919-1996), and is intended to celebrate his legacy in the theory and practice of software engineering.
A new neural network-based fault classification strategy for hard multiple faults in analog circuits is proposed. The magnitude of the harmonics of the Fourier components of the circuit response at different test node...
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A new neural network-based fault classification strategy for hard multiple faults in analog circuits is proposed. The magnitude of the harmonics of the Fourier components of the circuit response at different test nodes due to a sinusoidal input signal are first measured or simulated. A selection criterion for determining the best components that describe the circuit behaviour under fault-free (nominal) and fault situations is presented. An algorithm that estimates the overlap between different faults in the measurement space is also introduced. The learning vector quantization neural network is then effectively trained to classify circuit faults. Performance measures reveal very high classification accuracy in both training and testing stages. Two different examples, which demonstrate the proposed strategy, are described.
We present a new scalable architecture for the realization of fully programmable rank order filters (ROF), based on Capacitive Threshold Logic (CTL) gates. Variants of ROFs, especially median filters, are widely used ...
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ISBN:
(纸本)0780356322
We present a new scalable architecture for the realization of fully programmable rank order filters (ROF), based on Capacitive Threshold Logic (CTL) gates. Variants of ROFs, especially median filters, are widely used in digital signal and image/video processing and image enhancement. The CTL-based realization of the majority gates used in the ROF architecture allows the filter rank and the window size to be user-programmable, using a much smaller silicon area, compared to conventional realizations of digital median filters. The proposed filter architecture is completely modular and scalable, and the circuit complexity grows only linearly with maximum window size and with word length. Detailed post-layout simulations of the ROF prototype circuit indicate that the new architecture can accommodate sampling clock rates of up to 50 MHz, corresponding to an effective data processing rate of 800 Mb/s for a filter with window size 63 and word length of 16 bits.
Knowledge management is one of the most important goals of any organization. Therefore, several automatic tools are used for that purpose, e.g. Knowledge Based Systems (KBS), Experts Systems, Data Mining Applications ...
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Knowledge management is one of the most important goals of any organization. Therefore, several automatic tools are used for that purpose, e.g. Knowledge Based Systems (KBS), Experts Systems, Data Mining Applications and computer Aided Decision Systems. The validation and verification (V&V) process is fundamental in order to ensure the quality of used knowledge. The usage of automatic verification tools can be a reliable, inexpensive and reusable way to overcome the constant growth of the Knowledge Bases, the shortening of development times and the costs of Validation, specially field tests. This paper addresses the verification of Knowledge Based Systems, focussing on VERITAS, a verification tool initially developed to verify a KBS used to assist operators of Portuguese Transmission Control Centers in incident analysis and power restoration VERITAS performs knowledge base structural analysis allowing the detection of knowledge anomalies.
A key problem of finding the most complete and useful theory of consciousness may revolve around how to empirically determine different styles or states of consciousness and how to incorporate these within a single pa...
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A key problem of finding the most complete and useful theory of consciousness may revolve around how to empirically determine different styles or states of consciousness and how to incorporate these within a single paradigm. This was our motivation to start examination of EEG correlates of some activities or substates of consciousness which occur spontaneously or are induced artificially. Our investigations demonstrated more or less characteristic features in 25 subjects practicing the transcendental meditation program (increased β power in prefrontal region, increased θ power in left frontal and right temporal regions, increased α power in both temporal regions, and correlation between increased α power and decreased correlation dimension), 6 subjects with 4 types of spiritual music provided to induce musicogenic states (with significant changes in only 3 cases out of 24, where increased θ and α power was observed in only those subjects who have described their musical experiences as very pleasant), 28 subjects of relaxation induced by microwave resonance therapy applied to corresponding acupuncture points (with slightly decreased EEG power in all frequency bands, especially in the left central region, which can be ascribed to higher activation of the stimulated left circulatory part of the acupuncture system;it should be also noted that persons not previously subjected to this treatment responded stronger, presumably as a consequence of the more imbalanced acupuncture system), 5 healer/healee, noncontact interactions (with increase in the maximum mean coherence of their EEG patterns in the α band observed only in short 4 s time intervals), and 30 subjects for monitoring alertness/drowsiness level (with implemented automatic procedure of the neural network classifier to assess the correlation between EEG power spectrum fluctuations related to changes of vigilance level, demonstrating linear separability of the states of alert wakefulness and drowsy wakefulness, all
Balanced-realizations are attractive for adaptive filtering, due to their minimum parameter sensitivity and due to their usefulness in model-reduction problems. A balanced-realization based adaptive IIR filtering algo...
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Balanced-realizations are attractive for adaptive filtering, due to their minimum parameter sensitivity and due to their usefulness in model-reduction problems. A balanced-realization based adaptive IIR filtering algorithm is presented. The proposed algorithm uses a stochastic-gradient based search technique to minimize the output error. The algorithm inherently guarantees that the adaptive filter will always remain stable, which obviates the need for the usual stability check after adaptation. Since the algorithm minimizes the output error, the resulting estimates are unbiased. We try to avoid possible convergence to local minima of the output-error surface by using "good" initial estimates, as obtained from equation-error based adaptive filters. Simulation results show that the proposed algorithm converges to the global minimum of the output-error surface.
This article presents the results of a fixed millimeter-wave short-hop radio wave propagation study at 38 GHz. A wideband measurement campaign was performed using three cross-campus radio links from April to August 19...
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This article presents the results of a fixed millimeter-wave short-hop radio wave propagation study at 38 GHz. A wideband measurement campaign was performed using three cross-campus radio links from April to August 1998 at Virginia Tech. 73,963 power delay profiles (PDPs) were recorded during different weather events such as clear sky, rain, and hail. Rain/hail attenuation, short-term signal variation, and multipath statistics were studied. The measured rain attenuation (in excess of free space) slightly exceeds the Crane (see Electromagnetic Wave Propagation Through Rain. New York: John Wiley and Sons, 1996) model prediction. Short-term variation of received signal strength during rain follows a Rician distribution with a K factor inversely proportional to the rain rate. The wideband measurements indicate that multipath can occur due to foliage and reflections from wet surfaces during rain.
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