algorithm design usually has two ways to approach, deducing from a theory or inducing from practice. Many of algorithms for image processing were induced from practice. This paper will show how anew algorithm for medi...
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(纸本)1932415432
algorithm design usually has two ways to approach, deducing from a theory or inducing from practice. Many of algorithms for image processing were induced from practice. This paper will show how anew algorithm for medical image processing could be induced in a Matlab environment[1]. As an example, a new segmentation approach based on image algebraic operations for cryosection image background removing has been designed, implemented and tested by Matlab in a short time, which has showed that the Matlab Image Processing Toolbox from Math Works is an effective and easy been mastered tool for image processing algorithm design.
As an important variant of the Burrows-Wheeler Transform (BWT), the Sort Transform (ST) can speed up the transformation by sorting only a portion of the matrix. However, because the currently known inverse ST algorith...
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As an important variant of the Burrows-Wheeler Transform (BWT), the Sort Transform (ST) can speed up the transformation by sorting only a portion of the matrix. However, because the currently known inverse ST algorithms need to retrieve the complete k-order contexts and use hash tables, they are less efficient than the inverse BWT. In this paper, we propose three fast and memory-efficient inverse ST algorithms. The first algorithm uses two auxiliary vectors to replace the hash tables. The algorithm achieves O(kN) time and space complexities for a text of N characters under the context order k. The second uses two additional compact "alternate vectors" to further eliminate the need to restore all of the k-order contexts and achieve O(N) space complexity. Moreover, the third uses a "doubling technique" to further reduce the time complexity to O(N log2 k). The hallmark of these three algorithms is that they can invert the ST in a manner similar to inverting BWT in that they all make use of precalculated auxiliary mapping vectors and require no hash tables. These unifying algorithms can also better explain the connection between the BWT and the ST: Not only can their forward components be performed by the same algorithm framework, but their respective inverse components can also be efficiently conducted by the unifying algorithm framework proposed in the present work.
Collaborative filtering is one of the most widely adopted and successful recommendation approaches. Unlike approaches based on intrinsic consumer and product characteristics, CF characterizes consumers and products im...
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Collaborative filtering is one of the most widely adopted and successful recommendation approaches. Unlike approaches based on intrinsic consumer and product characteristics, CF characterizes consumers and products implicitly by their previous interactions. The simplest example is to recommend the most popular products to all consumers. Researchers are advancing CF technologies in such areas as algorithm design, human- computer interaction design, consumer incentive analysis, and privacy protection.
Symmetry is an obvious phenomenon in two-way communications. in this paper, we present an adaptive nonparametric method that can be used for anomaly detection in symmetric network traffic. Two important features are e...
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Symmetry is an obvious phenomenon in two-way communications. in this paper, we present an adaptive nonparametric method that can be used for anomaly detection in symmetric network traffic. Two important features are emphasized in this method: (i) automatic adjustment of the detection threshold according to the traffic conditions;and (ii) timely detection of the end of an anomalous event. Source-end defense against SYN flooding attacks is used to illustrate the efficacy of this method. Experiments on real traffic traces show that this method has high detection accuracy and low detection delays, and excels at detecting low intensity attacks. (c) 2007 Elsevier Ltd. All rights reserved.
An improved algorithm design methodology of vehicle airbag deployment decision is proposed in this paper. Firstly, the vehicle impact severity is analyzed to get four characteristic factors utilized as fuzzy inputs. F...
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An improved algorithm design methodology of vehicle airbag deployment decision is proposed in this paper. Firstly, the vehicle impact severity is analyzed to get four characteristic factors utilized as fuzzy inputs. From these four characteristics factors, the 'two stage fuzzy algorithm' is developed and used as the airbag deployment algorithm for identifying the vehicle impact severity. Finally, the adaptive-network-based fuzzy inference system (ANFIS) is used to train the suitable fuzzy membership functions and fuzzy rules based on crash data for improving the performance of the 'two stage fuzzy algorithm'. Simulation results for different vehicle crash data demonstrate the validity and effectiveness of the proposed design methodology. (C) 2007 Elsevier B.V. All rights reserved.
Given a sequence of n real numbers and an integer parameter k, the problem studied in this paper is to compute k subsequences of consecutive elements with the sums of their elements being the largest, the second large...
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Given a sequence of n real numbers and an integer parameter k, the problem studied in this paper is to compute k subsequences of consecutive elements with the sums of their elements being the largest, the second largest, and the kth largest among all possible range sums of the input sequence. For any value of k, 1 <= k <= n (n + 1)/2, we design a fast algorithm that takes O (n + k log n) time in the worst case to compute and rank all such subsequences. We also prove that our algorithm is optimal for k = O (n) by providing a matching lower bound. Moreover, our algorithm is an improvement over the previous results on the maximum sum subsequences problem (where only the subsequences are requested and no ordering with respect to their relative sums will be determined). Furthermore, given the fact that we have computed the fth largest sums, our algorithm retrieves the (l + 1)th largest sum in O (log n) time, after O (n) time of preprocessing. (c) 2007 Elsevier B.V. All rights reserved.
The hydraulic spline algorithm generates irregular 2D channel grids from highly accurate cross-sectional survey data at any desired resolution, facilitating its integration with high-density light detection and rangin...
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The hydraulic spline algorithm generates irregular 2D channel grids from highly accurate cross-sectional survey data at any desired resolution, facilitating its integration with high-density light detection and ranging (lidar) data.
In this article, we describe a multiagent application that configures Semantic Web services following a design problem solving method. For that, a propose-and-revise strategy was modeled and implemented in OWL-S. The ...
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In this article, we describe a multiagent application that configures Semantic Web services following a design problem solving method. For that, a propose-and-revise strategy was modeled and implemented in OWL-S. The other contribution of this method is the extension of OWL-S for recording the service execution flow followed by the agent. The trace of the agent's reasoning is stored in node sets represented in a proof markup language, which make up a framework for explanations on the Web. The proposed approach is shown to be useful in the context of e-business where the workflow definition of services is automatically performed by the agents in order to configure a computer from a customer order.
In this paper, we address an optimization problem that arises in the context of cache placement in sensor networks. In particular, we consider the cache placement problem where the goal is to determine a set of nodes ...
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In this paper, we address an optimization problem that arises in the context of cache placement in sensor networks. In particular, we consider the cache placement problem where the goal is to determine a set of nodes in the network to cache/store the given data item, such that the overall communication cost incurred in accessing the item is minimized, under the constraint that the total communication cost in updating the selected caches is less than a given constant. In our network model, there is a single server (containing the original copy of the data item) and multiple client nodes (that wish to access the data item). For various settings of the problem, we design optimal, near-optimal, heuristic-based, and distributed algorithms, and evaluate their performance through simulations on randomly generated sensor networks. (C) 2006 Published by Elsevier B.V.
We theoretically propose a procedure based on a cascading genetic algorithm for the design of aperiodically quasi-phase-matched gratings for frequency conversion of optical ultrafast pulses during difference-frequency...
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We theoretically propose a procedure based on a cascading genetic algorithm for the design of aperiodically quasi-phase-matched gratings for frequency conversion of optical ultrafast pulses during difference-frequency generation. By designing the sequence of a domain inversion grating, different wavelengths at the output idler pulse almost have the same phase response, so femtosecond laser pulses at wavelength 800 nm can be shifted to other wavelengths without group-velocity mismatch. (C) 2007 Optical Society of America.
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