Data Grids seek to harness geographically distributed resources for large-scale data-intensive problems. Such problems, involving loosely coupled jobs and large data-sets, are found in fields like high-energy physics,...
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We propose a new scheme based on wavelet transform to extract skeleton of ribbon-like shapes. The development of the method depending on a new wavelet function which is designed specifically for computing the medial a...
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ISBN:
(纸本)9812389784
We propose a new scheme based on wavelet transform to extract skeleton of ribbon-like shapes. The development of the method depending on a new wavelet function which is designed specifically for computing the medial axis of ribbon-like objects and it yields certain desirable properties that make the resulting object skeleton robust against variations in grey level, variation in slope of the edge, as well as independent of the width of the ribbon object and efficient computation of the medial axis. A set of modified technique for primary wavelet skeleton based on multiscale corner detection by using wavelet transform 3 are developed.
A recent study by Graham and Takis Metaxas [Graham, L., & Takis Metaxas, P. (2002). Of course it is true, I read it on the Internet . Unpublished manuscript, Wellesley College, MA] suggests that many college stude...
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A Query by Humming system allows the user to find a song by humming part of the tune. No musical training is needed. Previous query by humming systems have not provided satisfactory results for various reasons. Some s...
ISBN:
(纸本)9781581136340
A Query by Humming system allows the user to find a song by humming part of the tune. No musical training is needed. Previous query by humming systems have not provided satisfactory results for various reasons. Some systems have low retrieval precision because they rely on melodic contour information from the hum tune, which in turn relies on the error-prone note segmentation process. Some systems yield better precision when matching the melody directly from audio, but they are slow because of their extensive use of Dynamic Time Warping (DTW). Our approach improves both the retrieval precision and speed compared to previous approaches. We treat music as a time series and exploit and improve well-developed techniques from time series databases to index the music for fast similarity queries. We improve on existing DTW indexes technique by introducing the concept of envelope transforms, which gives a general guideline for extending existing dimensionality reduction methods to DTW indexes. The net result is high scalability. We confirm our claims through extensive experiments.
Fuzzy variable is a function from a possibility space to the real line. In this paper, two classes of fuzzy programming problems with fuzzy variable coefficients are presented. The first one is called primal fuzzy pro...
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Fuzzy variable is a function from a possibility space to the real line. In this paper, two classes of fuzzy programming problems with fuzzy variable coefficients are presented. The first one is called primal fuzzy programming problem whose objective is a chance function defined by possibility measure, while the second one is called inverse fuzzy programming problem whose objective is a critical value function. Generally, the difficulties of solving the two fuzzy programming problems are different. Thus, to solve the problems effectively, we prove two main results which show solving one of the problems is equivalent to solving its counterpart.
Most database management systems maintain statistics on the underlying relation. One of the important statistics is that of the "hot items" in the relation: those that appear many times (most frequently, or ...
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Most database management systems maintain statistics on the underlying relation. One of the important statistics is that of the "hot items" in the relation: those that appear many times (most frequently, or more than some threshold). For example, end-biased histograms keep the hot items as part of the histogram and are used in selectivity estimation. Hot items are used as simple outliers in data mining, and in anomaly detection in networking applications. We present a new algorithm for dynamically determining the hot items at any time in the relation that is undergoing deletion operations as well as inserts. Our algorithm maintains a small space data structure that monitors the transactions on the relation, and when required, quickly outputs all hot items, without rescanning the relation in the database. With user-specified probability, it is able to report all hot items. Our algorithm relies on the idea of "group testing", is simple to implement, and has provable quality, space and time guarantees. Previously known algorithms for this problem that make similar quality and performance guarantees can not handle deletions, and those that handle deletions can not make similar guarantees without rescanning the database. Our experiments with real and synthetic data shows that our algorithm is remarkably accurate in dynamically tracking the hot items independent of the rate of insertions and deletions.
Fuzzy random variable has been defined in several ways in literature. This paper presents a new definition of fuzzy random variable, and gives a novel definition of scalar expected value operator for fuzzy random vari...
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Fuzzy random variable has been defined in several ways in literature. This paper presents a new definition of fuzzy random variable, and gives a novel definition of scalar expected value operator for fuzzy random variables. Some properties concerning the measurability of fuzzy random variable are also discussed. In addition, the concept of independent and identically distributed fuzzy random variables is introduced. Finally, a type of law of large numbers is proved.
The MPI Standard supports derived datatypes, which allow users to describe noncontiguous memory layout and communicate noncontiguous data with a single communication function. This feature enables an MPI implementatio...
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Human perception is a complex nonlinear dynamics. On the one hand it is periodic dynamics and on the other hand it is chaotic. Thus, we wish to propose a hybrid - the spatial chaotic dynamics for the associative recal...
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Human perception is a complex nonlinear dynamics. On the one hand it is periodic dynamics and on the other hand it is chaotic. Thus, we wish to propose a hybrid - the spatial chaotic dynamics for the associative recall to retrieve patterns, similar to Walter Freeman's discovery, and the fixed point dynamics for memory storage, similar to Hopfield and Grossberg's discoveries. In this model, each neuron in the network could be a chaotic map, whose phase space is divided into two states: one is periodic dynamic state with period-V, which is used to represent a V-value retrieved pattern;another is chaotic dynamic state. Firstly, patterns are stored in the memory by fixed point learning algorithm. In the retrieving process, all neurons are initially set in the chaotic region. Due to the ergodicity property of chaos, each neuron will approximate the periodic points covered by the chaotic attractor at same instants. When this occurs, the control is activated to drive the dynamic of each neuron to their corresponding stable periodic point. computer simulations confirm the theoretical prediction.
Although the classical B-tree and its derivatives are space efficient data structures for small string documents, they require many structures and an excessive amount of pointer manipulations for efficiently processin...
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Although the classical B-tree and its derivatives are space efficient data structures for small string documents, they require many structures and an excessive amount of pointer manipulations for efficiently processing and searching large documents. In this paper, we propose a new and conceptually powerful data structure, called multidimensional suffix arrays (MSA), for string search. This data structure combines the features of suffix arrays and multilevel structures into a new approach which is very amenable to implementation on both conventional and clustered computers. Algorithms for searching, updating, reorganizing, and distributing multidimensional suffix arrays are discussed. Moreover, MSA achieve a significant improvement over string B-trees.
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