The adaptive bootstrap separator has been shown to perform better than the conventional decorrelation detector when used for synchronous code division multiple access (CDMA) channels, or with a one-shot matched filter...
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The adaptive bootstrap separator has been shown to perform better than the conventional decorrelation detector when used for synchronous code division multiple access (CDMA) channels, or with a one-shot matched filter bank for asynchronous channels when the cross-correlation of the partial sequences is nonsingular. In the later case, however, when the "partial cross-correlation" is singular, the separator weights fail to converge. We propose the use of a soft-limiting decision inst.ad of a hard limiter for controlling the adaptive weights of the separator. We show that the algorithm weights converge, provided that the limiting threshold is not zero or not very large. Due to analytical difficulties, the actual steady state weights are not found, but are shown to exist. Simulation results support these claims. The bit error rate (BER) performance of the adaptive soft limiter bootstrap separator are also found by simulation and compared to the performance of the conventional decorrelator that uses the pseudoinverse of the cross-correlation matrix.
We introduce a hypermedia-based distributed design image database system that can provide simple and flexible user access capabilities based on the "kansei" link method. As proof of this concept, we have dev...
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We introduce a hypermedia-based distributed design image database system that can provide simple and flexible user access capabilities based on the "kansei" link method. As proof of this concept, we have developed a prototype distributed multimedia information network incorporating the DHS model. Dubbed the Textile Design Image Database System (TDIDS), this database aids designers using apparel computer-aided design (CAD) systems in different locations, collaborating or working separately, in the design of clothes, including kimonos. Our purpose has been to create a database that will allow each designer to make the best use of his or her creativity and originality-his or her "style and sensitivity to beauty," or, in Japanese, kansei. In our hypermedia system, "metanodes" are defined as abstract nodes that are dynamically organized by multimedia objects, while "metalinks" are defined as flexible kansei links. Metanodes and metalinks are combined to organize a dynam ic hypermedia space from which users can easily retrieve desired design image objects by querying a knowledge agent. The knowledge agent, utilizing the knowledge base, creates links from kansei word objects provided by the user to suitable design image objects among those stored on multimedia databases distributed across the network. The knowledge agent also performs query conversion of individual users' subjective kansei (idiosyncratic, subjective use of kansei words) into objective kansei words using each user's own "user model," These objective kansei words are then converted to equivalent color values. Color value is the means by which all stored design images are characterized. This dynamic linking of kansei word objects to equivalent design images allows individual users' kansei to influence the retrieval process. The sophisticated and flexible CAD systems of the future will require multimedia database systems with cooperative supporting capabilities similar to our kansei system.
Over 25 implementations of different functional languages are benchmarked using the same program, a floating-point intensive application taken from molecular biology. The principal aspects studied are compile time and...
Over 25 implementations of different functional languages are benchmarked using the same program, a floating-point intensive application taken from molecular biology. The principal aspects studied are compile time and execution time for the various implementations that were benchmarked. An important consideration is how the program can be modified and tuned to obtain maximal performance on each language implementation. With few exceptions, the compilers take a significant amount of time to compile this program, though most compilers were faster than the then current GNU C compiler (GCC version 2.5.8). Compilers that generate C or Lisp are often slower than those that generate native code directly: the cost of compiling the intermediate form is normally a large fraction of the total compilation time. There is no clear distinction between the runtime performance of eager and lazy implementations when appropriate annotations are used: lazy implementations have clearly come of age when it comes to implementing largely strict applications, such as the Pseudoknot program. The speed of C can be approached by some implementations, but to achieve this performance, special measures such as strictness annotations are required by non-strict implementations. The benchmark results have to be interpreted with care. Firstly, a benchmark based on a single program cannot cover a wide spectrum of 'typical' applications. Secondly, the compilers vary in the kind and level of optimisations offered, so the effort required to obtain an optimal version of the program is similarly varied.
This paper describes a novel approach for nonorthogonal representation of signals using Gaussians and an extension of this method for Gabor representation of signals, based on the equivalence of Gabor expansion to Gau...
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This paper describes a novel approach for nonorthogonal representation of signals using Gaussians and an extension of this method for Gabor representation of signals, based on the equivalence of Gabor expansion to Gaussian expansion in the frequency domain. The Gaussian expansion scheme yields an efficient representation of signals for low number of bits per pixel and is better than the corresponding Discrete Cosine Transform (DCT) representation for very low bit rates, This advantage diminishes gracefully for higher bit rates where the residual approximation error signal to be represented is more random and less structured. It is proved in this paper that a finite number of Gaussians can theoretically approximate sinusoids in a bounded region with arbitrarily small error, and therefore any finite support L(2)(R) signal as well. Two methods for Gaussian representation of signals are outlined, The first, called the Max-Energy paradigm, involves successive extraction of the highest energy Gaussian that best ''fits'' the signal. The second is a parallel approach and uses an adaptive projection algorithm to first derive the Gaussian basis set to be used in parallel, and then optimizes the coefficients for minimum squared error.
Biotechnology is poised to have a major impact on the delivery of health care, through the development of new drugs and products for diagnosis and monitoring. It is providing and will continue to provide new and excit...
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Biotechnology is poised to have a major impact on the delivery of health care, through the development of new drugs and products for diagnosis and monitoring. It is providing and will continue to provide new and exciting research opportunities for Biomedical engineering. Biotechnology has grown into an important area in which many significant engineering and scientific challenges exist. Vital research in biotechnology is identified especially as they relate to areas in which biomedical engineers could contribute, i.e., in biosensing, control, signal analysis, and computer applications.< >
Discrete-event simulation is undergoing a revolution brought on, in part, by two related technological advances. The first advance is in large distributed computin g systems which are becoming more and more common. Di...
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In this paper, we consider the problem of solving a sparse system of linear equations using a new LU factorization based algorithm. The algorithm employs a new technique called two-sided factorization to produce the c...
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In this paper, we consider the problem of solving a sparse system of linear equations using a new LU factorization based algorithm. The algorithm employs a new technique called two-sided factorization to produce the complete solution by solving only one triangular system after the factorization phase against.the solution of two triangular systems in the existing LU factorization based methods. The effectiveness of the new algorithm in solving sparse linear systems on hypercubes is demonstrated using IEEE standard power system networks as benchmarks.
The paper presents a model for the fast fading first and second-order statistics (amplitude distribution, level crossing rate and average duration of fades) of the received signal in millimeter communications in an ur...
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The paper presents a model for the fast fading first and second-order statistics (amplitude distribution, level crossing rate and average duration of fades) of the received signal in millimeter communications in an urban environment. The model starts from physical considerations to infer the form of the functions representing the desired statistics. Their complete description requires the evaluation of a small number of parameters. Again from physical considerations it is determined how these parameters are related to the geometry of the operating environment in such a way that they can, for example, be computed with the help of computer graphics techniques. The model is then applied to the case of a long street, for which analytical results can be easily obtained. The results obtained from the model are compared with results obtained by simulation via ray tracing.
To successfully apply a multilayered perceptron neural network (NN) to pattern recognition, the feature vectors fed into the NN must contain rich representative information so that the NN is able to distinguish the pa...
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ISBN:
(纸本)0780325591
To successfully apply a multilayered perceptron neural network (NN) to pattern recognition, the feature vectors fed into the NN must contain rich representative information so that the NN is able to distinguish the patterns belonging to different classes. For optical character recognition (OCR), the feature vectors, hence, must be endowed with a distortion insensitive property. In the paper, the authors propose a 5-layer perceptron (3 hidden layers) for OCR. One hidden layer is dedicated to extract the so-called Gaussian-vector-field (GVF) feature, which is insensitive to patterns deformed in shapes, of input characters. The other two hidden layers perform hyperregion encoding and decoding functions. A traditional error-propagation learning algorithm is used to train the NN for classifying hand-written numeric characters. Simulation result shows that the MLP can tolerate a large degree of pattern distortion. Furthermore, the size of the MLP is quite small when compared with the other approaches.
An English to Indian languages machine aided translation system, named ANGLABHARTI, has been developed. It uses pattern directed approach using context free grammar like structures. A 'pseudo-target' is genera...
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An English to Indian languages machine aided translation system, named ANGLABHARTI, has been developed. It uses pattern directed approach using context free grammar like structures. A 'pseudo-target' is generated which is applicable to a group of Indian languages. Set of rules are acquired through corpus analysis to identify the plausible constituents with respect to which movement rules for the 'pseudo-target' are constructed. A number of semantic tags are used to resolve sense ambiguity in the source language. Alternative meanings for the unresolved ambiguities are retained in the pseudo target language code. A text generator module for each of the target languages transforms the pseudo target language to the target language. A corrector for ill-formed sentences is used for each of the target languages. Finally, a human-engineered post-editing package is used to make the final corrections. The post-editor needs to know only the target language. The strategy used in ANGLABHARTI lies in between the transfer and the interlingua approach. It is better than the transfer approach, as the translation is valid for a host of target language sentences, but falls short of genuine interlingua, in the sense that it ignores complete disambiguation/understanding of the text to be translated.
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