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Conference on Detection and Sensing of Mines, Explosive Objects, and Obscured Targets XVI

作者： Nasif, Ahmed O. Mark, Brian L. Hintz, Kenneth J. George Mason Univ Dept Elect & Comp Engn Fairfax VA 22030 USA

ISBN: (纸本)9780819485915

Syntactic landmine detection has been proposed to detect and classify non-metallic landmines using ground penetrating radar (GPR). In this approach, the GPR return is processed to extract characteristic binary strings for landmine and clutter discrimination. In our previous work, we discussed the preprocessing methodology by which the amplitude information of the GPR A-scan signal can be effectively converted into binary strings, which identify the impedance discontinuities in the signal. In this work, we study the statistical properties of the binary string space. In particular, we develop a Markov chain model to characterize the observed bit sequence of the binary strings. The state is defined as the number of consecutive zeros between two ones in the binarized A-scans. Since the strings are highly sparse (the number of zeros is much greater than the number of ones), defining the state this way leads to fewer number of states compared to the case where each bit is defined as a state. The number of total states is further reduced by quantizing the number of consecutive zeros. In order to identify the correct order of the Markov model, the mean square difference (MSD) between the transition matrices of mine strings and non-mine strings is calculated up to order four using training data. The results show that order one or two maximizes this MSD. The specification of the transition probabilities of the chain can be used to compute the likelihood of any given string. Such a model can be used to identify characteristic landmine strings during the training phase. These developments on modeling and characterizing the string statistics can potentially be part of a real-time landmine detection algorithm that identifies landmine and clutter in an adaptive fashion.

关键词： Landmine detection Ground penetrating radar Syntactic pattern recognition binary string Markov chain

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Quadratic Conditional Lower Bounds for string Problems and Dynamic TimeWarping 56

Quadratic Conditional Lower Bounds for String Problems and D...

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56th IEEE Annual Symposium on Foundations of Computer Science (FOCS)

作者： Bringmann, Karl Kuennemann, Marvin Swiss Fed Inst Technol Inst Theoret Comp Sci Zurich Switzerland Max Planck Inst Informat Saarbrucken Germany Saarbrucken Grad Sch Comp Saarbrucken Germany

ISBN: (纸本)9781467381918

Classic similarity measures of strings are longest common subsequence and Levenshtein distance (i.e., the classic edit distance). A classic similarity measure of curves is dynamic time warping. These measures can be computed by simple O(n(2)) dynamic programming algorithms, and despite much effort no algorithms with significantly better running time are known. We prove that, even restricted to binary strings or one-dimensional curves, respectively, these measures do not have strongly subquadratic time algorithms, i.e., no algorithms with running time O(n(2-epsilon)) for any epsilon > 0, unless the Strong Exponential Time Hypothesis fails. We generalize the result to edit distance for arbitrary fixed costs of the four operations (deletion in one of the two strings, matching, substitution), by identifying trivial cases that can be solved in constant time, and proving quadratic-time hardness on binary strings for all other cost choices. This improves and generalizes the known hardness result for Levenshtein distance [Backurs, Indyk STOC' 15] by the restriction to binary strings and the generalization to arbitrary costs, and adds important problems to a recent line of research showing conditional lower bounds for a growing number of quadratic time problems. As our main technical contribution, we introduce a framework for proving quadratic-time hardness of similarity measures. To apply the framework it suffices to construct a single gadget, which encapsulates all the expressive power necessary to emulate a reduction from satisfiability. Finally, we prove quadratic-time hardness for longest palindromic subsequence and longest tandem subsequence via reductions from longest common subsequence, showing that conditional lower bounds based on the Strong Exponential Time Hypothesis also apply to string problems that are not necessarily similarity measures.

关键词： Approximation algorithms Computer science Current measurement Dynamic programming Heuristic algorithms Time measurement binary string time measurement Electric current measurement Current measuring computer science Heuristic algorithms dynamic programming Approximation algorithms dynamic time warping similar measure Cosmic strings Levenshtein distance Lower bound Runtime Conditional

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Repairing the crossover rate in adaptive differential evolution

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APPLIED SOFT COMPUTING 2014年第0期15卷 149-168页

作者： Gong, Wenyin Cai, Zhihua Wang, Yang China Univ Geosci Sch Comp Sci Wuhan 430074 Peoples R China

Differential evolution (DE) is a simple yet powerful evolutionary algorithm (EA) for global numerical optimization. However, its performance is significantly influenced by its parameters. Parameter adaptation has been proven to be an efficient way for the enhancement of the performance of the DE algorithm. Based on the analysis of the behavior of the crossover in DE, we find that the trial vector is directly related to its binary string, but not directly related to the crossover rate. Based on this inspiration, in this paper, we propose a crossover rate repair technique for the adaptive DE algorithms that are based on successful parameters. The crossover rate in DE is repaired by its corresponding binary string, i.e. by using the average number of components taken from the mutant. The average value of the binary string is used to replace the original crossover rate. To verify the effectiveness of the proposed technique, it is combined with an adaptive DE variant, JADE, which is a highly competitive DE variant. Experiments have been conducted on 25 functions presented in CEC-2005 competition. The results indicate that our proposed crossover rate technique is able to enhance the performance of JADE. In addition, compared with other DE variants and state-of-the-art EAs, the improved JADE method obtains better, or at least comparable, results in terms of the quality of final solutions and the convergence rate. (C) 2013 Elsevier B.V. All rights reserved.

关键词： Differential evolution Parameter adaptation Crossover rate repair binary string Numerical optimization

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BWDO algorithm and its application in antenna array and pixelated metasurface synthesis

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IET MICROWAVES ANTENNAS & PROPAGATION 2019年第9期13卷 1263-1270页

作者： Ranjan, Prakash Mahto, Santosh Kumar Choubey, Arvind Natl Inst Technol Jamshedpur Dept Elect & Commun Engn Jamshedpur Bihar India NIT Jamshedpur Dept Elect & Commun Engn Indian Inst Informat Technol Ranchi Jamshedpur Bihar India

This article introduces a novel, binary version of wind driven optimisation (WDO) called binary WDO (BWDO), which can be specifically used for solving binary valued problems such as antenna array and metasurface synthesis. Validation of proposed algorithm is done with standard benchmark functions. To demonstrate the efficiency of BWDO, examples of thinned antenna array and metasurface synthesis are considered. Thinned antenna array problem is solved by formulating single and multi-objective optimisation problems which achieve minimum SLL of -22.30 dB and -20.28 dB respectively, as compared to -13.2 dB by periodic array. Further, the proposed BWDO algorithm is interface with Ansys-HFSS and three design examples of metasurfaces such as MPA and AMC are further considered to exemplify the proficiency of BWDO. Simulation of optimised MPA exhibits five discrete bands of high absorptions at 8.7, 9.7, 14.6, 15.3 and 16.5 GHz with simulation reflection co-efficient value of -11.46, -10.00, -12.17, -16.19 and -20.58 dB which is less than -10 dB reflection under normal incidence of wave. Synthesised single and dual band AMC has in-phase reflection bandwidth of 0.58 and 0.34, 0.16 GHz at central frequency of 5.21 and 5.07, 6.49 GHz respectively. The measured results almost matched with the respective simulated results with slight variation due to fabrication tolerance.

关键词： optimisation antenna arrays frequency selective surfaces conductors (electric) antenna radiation patterns electromagnetic wave reflection electromagnetic wave absorption metamaterial antennas synthesised metasurfaces BWDO algorithm metasurface synthesis binary version wind driven optimisation binary-valued problems standard benchmark functions multiobjective optimisation problems minimum side-lobe level periodic array frequency selective surface human experience standard WDO algorithm electromagnetic problems binary string artificial magnetic conductor reflection coefficient value trial-and-error technology single objective optimisation problems antenna array problem frequency 0 16 GHz frequency 8 7 GHz frequency 6 49 GHz frequency 9 7 GHz frequency 14 6 GHz frequency 15 3 GHz frequency 16 5 GHz frequency 0 58 GHz frequency 0 34 GHz frequency 5 21 GHz frequency 5 07 GHz

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THEORETICAL COMPUTER SCIENCE 2016年 638卷 76-90页

作者： Apostolico, Alberto Guerra, Concettina Landau, Gad M. Pizzi, Cinzia Georgia Inst Technol Coll Comp 801 Atlantic Dr Atlanta GA 30318 USA CNR Ist Anal Sistemi & Informat Rome Italy Univ Haifa Dept Comp Sci IL-31905 Haifa Israel NYU MetroTech Ctr 6 NYU Polytech Sch Engn Dept Comp Sci & Engn Brooklyn NY 11201 USA Univ Padua Dipartimento Ingn Informaz Via Gradenigo 6-A I-30131 Padua Italy

A growing number of measures of sequence similarity are being based on some underlying notion of relative compressibility. Within this paradigm, similar sequences are expected to share a large number of common substrings, or subsequences, or more complex patterns or motifs, and so on. In this paper, measures of sequence similarity are introduced and studied in which patterns in a pair are considered similar if they coincide up to a preset number of mismatches, that is, within a bounded Hamming distance. It is shown here that for some such measures bounds are achievable that are slightly better than O(n(2)). Preliminary experiments demonstrate the potential applicability to phylogeny and classification of these similarity measures. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Pattern matching string comparison Alignment free distances binary string Longest common substring Mismatches

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Anomaly detection in ECG based on trend symbolic aggregate approximation

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MATHEMATICAL BIOSCIENCES AND ENGINEERING 2019年第4期16卷 2154-2167页

作者： Zhang, Chunkai Chen, Yingyang Yin, Ao Wang, Xuan Harbin Inst Technol Dept Comp Sci & Technol Shenzhen Peoples R China

ECG anomaly detection is a necessary approach to detect disease Electrocardiography(ECG) signals before the detail diagnosis process in medical field to gauge the health of the human heart. Nowadays, there are many anomaly detection methods for ECG detection including supervised learning and unsupervised learning. For supervised learning, it requires the knowledge of expert and different types of Arrhythmia data for training. However, since the anomalies are less and unknown in many cases which are difficult to distinguish and be labeled, unsupervised methods are more suitable to detect the ECG anomalies. Furthermore, the existing unsupervised learning studies do not take ECG shape into account where different diseases have different shapes. In this paper, a novel simple trend aggregate approximation method is proposed, the relative binary trend representation are used to record the shape feature in original time series and to detect the anomaly heart signals by similarity comparison. We use the ECG dataset in UCR Time Series Classification Archive to obtain ECG time series data and the experiment results are assessed by means of sensitivity, specificity, false alarm rate measures which is robust and promising with high accuracy.

关键词： similarity measurement trend distance electrocardiography anomaly detection binary string

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Automated type synthesis of planar mechanisms using numeric optimization with genetic algorithms

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JOURNAL OF MECHANICAL DESIGN 2005年第5期127卷 910-916页

作者： Liu, Y McPhee, J Univ Waterloo Dept Syst Design Engn Waterloo ON N2L 3G1 Canada

This paper presents a novel method for the automated type synthesis of planar mechanisms and multibody systems. The method explicitly includes topology as a design variable in an optimization framework based on a genetic algorithm (GA). Each binary string genome of the GA represents the concatenation of the upper-right triangular portion of the link adjacency matrix of a mechanism. Different topologies can be explored by the GA by applying genetic operators to the genomes. The evolutionary process is not dependent on the results obtained from enumeration. Two examples of topology-based optimization show the applicability of this method to mechanism type synthesis problems. This method is distinct from others in the literature in that it represents the first fully automated algorithm for solving a general type synthesis problem with the help of a numeric optimizer.

关键词： Genetic Algorithm (GA) binary string Planar topology Genome Genetic Operator bar linkage Gallium design variable synthesis Automation

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A linear-time normalization of one-dimensional quadtrees

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IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 1998年第3期E81D卷 271-277页

作者： Ito, A Inoue, K Wang, Y Yamaguchi Univ Fac Engn Ube Yamaguchi 7558611 Japan

Given a binary picture represented by a region quadtree, it is desirable to identify the amount of (rightward and downward) shifts of the foreground components such that it gives the minimum number of nodes of its quadtree. This problem is called "quadtree normalization." For this problem, it is unknown whether there exists a linear time algorithm with respect to the size of given images (i.e., the number of pixels). In this study, we investigate the "one-dimensional version" of the quadtree normalization problem, i.e., given a binary string represented by a regional binary tree, the task is to identify the amount of (rightward) shift of the foreground components such that it gives the minimum number of nodes of its binary tree. We show that there exists a linear time algorithm for this version.

关键词： quadtree normalization binary string linear time

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EXTRACTING BIOMETRIC binary stringS WITH MINIMAL AREA UNDER THE FRR CURVE FOR THE HAMMING DISTANCE CLASSIFIER

EXTRACTING BIOMETRIC BINARY STRINGS WITH MINIMAL AREA UNDER ...

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European signal processing conference

作者： Chun Chen Raymond Veldhuis Signals and Systems Group Electrical Engineering University of Twente P.O. Box 217 7500AE Enschede The Netherlands

ISBN: (纸本)9781617388767

Quantizing real-valued templates into binary strings is a fundamental step in biometric compression and template protection. In this paper, we introduce the area under the FRR curve optimize bit allocation (AUF-OBA) principle. Given the bit error probability, AUF-OBA assigns the numbers of quantization bits to every feature, in such way that the analytical area under the false rejection rate (FRR) curve for a Hamming distance classifier (HDC) is minimized. Experiments on the FRGC face database yield good performances.

关键词： fast retransmit and recovery binary string Quantization binary Hamming distance Road

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A New Substring Searching Algorithm

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IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 2014年第7期E97D卷 1893-1896页

作者： Zhao, Xiao Li, Sihui Yang, Yun Chao, Yuyan He, Lifeng Shaanxi Univ Sci & Technol Coll Elect & Informat Engn Artificial Intelligence Inst Xian 710021 Shaanxi Peoples R China Nagoya Sangyo Univ Grad Sch Environm Management Owariasahi 4888711 Japan Aichi Prefectural Univ Grad Sch Informat Sci & Technol Nagakute Aichi 4801198 Japan

This paper proposes a new algorithm for substring searching. Our algorithm is an improvement on the famous BM algorithm. When a mismatch happens while searching a substring (pattern), the BM algorithm will use two strategies to calculate shifting distances of the substring respectively and selects the larger one. In comparison, our algorithm uses each of the two strategies for their most suitable cases separately without a selection operation. Experimental results demonstrated that our algorithm is more efficient than the BM algorithm and the Quick Search algorithm, especially for binary strings and DNA strings.

关键词： substring searching pattern matching binary string DNA matching

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