The search functionality is under construction.
The search functionality is under construction.

Keyword Search Result

[Keyword] metric(675hit)

141-160hit(675hit)

  • Construction of odd-Variable Rotation Symmetric Boolean Functions with Maximum Algebraic Immunity

    Shaojing FU  Jiao DU  Longjiang QU  Chao LI  

     
    LETTER-Cryptography and Information Security

      Vol:
    E99-A No:4
      Page(s):
    853-855

    Rotation symmetric Boolean functions (RSBFs) that are invariant under circular translation of indices have been used as components of different cryptosystems. In this paper, odd-variable balanced RSBFs with maximum algebraic immunity (AI) are investigated. We provide a construction of n-variable (n=2k+1 odd and n ≥ 13) RSBFs with maximum AI and nonlinearity ≥ 2n-1-¥binom{n-1}{k}+2k+2k-2-k, which have nonlinearities significantly higher than the previous nonlinearity of RSBFs with maximum AI.

  • Fast Mode Decision Technique for HEVC Intra Prediction Based on Reliability Metric for Motion Vectors

    Chihiro TSUTAKE  Yutaka NAKANO  Toshiyuki YOSHIDA  

     
    PAPER-Image Processing and Video Processing

      Pubricized:
    2016/01/21
      Vol:
    E99-D No:4
      Page(s):
    1193-1201

    This paper proposes a fast mode decision technique for intra prediction of High Efficiency Video Coding (HEVC) based on a reliability metric for motion vectors (RMMV). Since such a decision problem can be regarded as a kind of pattern classification, an efficient classifier is required for the reduction of computation complexity. This paper employs the RMMV as a classifier because the RMMV can efficiently categorize image blocks into flat(uniform), active, and edge blocks, and can estimate the direction of an edge block as well. A local search for angular modes is introduced to further speed up the decision process. An experiment shows the advantage of our technique over other techniques.

  • Defending DDoS Attacks in Software-Defined Networking Based on Legitimate Source and Destination IP Address Database

    Xiulei WANG  Ming CHEN  Changyou XING  Tingting ZHANG  

     
    PAPER-Network security

      Pubricized:
    2016/01/13
      Vol:
    E99-D No:4
      Page(s):
    850-859

    The availability is an important issue of software-defined networking (SDN). In this paper, the experiments based on a SDN testbed showed that the resource utilization of the data plane and control plane changed drastically when DDoS attacks happened. This is mainly because the DDoS attacks send a large number of fake flows to network in a short time. Based on the observation and analysis, a DDoS defense mechanism based on legitimate source and destination IP address database is proposed in this paper. Firstly, each flow is abstracted as a source-destination IP address pair and a legitimate source-destination IP address pair database (LSDIAD) is established by historical normal traffic trace. Then the proportion of new source-destination IP address pair in the traffic per unit time is cumulated by non-parametric cumulative sum (CUSUM) algorithm to detect the DDoS attacks quickly and accurately. Based on the alarm from the non-parametric CUSUM, the attack flows will be filtered and redirected to a middle box network for deep analysis via south-bound API of SDN. An on-line updating policy is adopted to keep the LSDIAD timely and accurate. This mechanism is mainly implemented in the controller and the simulation results show that this mechanism can achieve a good performance in protecting SDN from DDoS attacks.

  • Efficient Geometric Routing in Large-Scale Complex Networks with Low-Cost Node Design

    Sahel SAHHAF  Wouter TAVERNIER  Didier COLLE  Mario PICKAVET  Piet DEMEESTER  

     
    PAPER-Network

      Vol:
    E99-B No:3
      Page(s):
    666-674

    The growth of the size of the routing tables limits the scalability of the conventional IP routing. As scalable routing schemes for large-scale networks are highly demanded, this paper proposes and evaluates an efficient geometric routing scheme and related low-cost node design applicable to large-scale networks. The approach guarantees that greedy forwarding on derived coordinates will result in successful packet delivery to every destination in the network by relying on coordinates deduced from a spanning tree of the network. The efficiency of the proposed scheme is measured in terms of routing quality (stretch) and size of the coordinates. The cost of the proposed router is quantified in terms of area complexity of the hardware design and all the evaluations involve comparison with a state-of-the-art approach with virtual coordinates in the hyperbolic plane. Extensive simulations assess the proposal in large topologies consisting of up to 100K nodes. Experiments show that the scheme has stretch properties comparable to geometric routing in the hyperbolic plane, while enabling a more efficient hardware design, and scaling considerably better in terms of storage requirements for coordinate representation. These attractive properties make the scheme promising for routing in large networks.

  • Protein Fold Classification Using Large Margin Combination of Distance Metrics

    Chendra Hadi SURYANTO  Kazuhiro FUKUI  Hideitsu HINO  

     
    PAPER-Pattern Recognition

      Pubricized:
    2015/12/14
      Vol:
    E99-D No:3
      Page(s):
    714-723

    Many methods have been proposed for measuring the structural similarity between two protein folds. However, it is difficult to select one best method from them for the classification task, as each method has its own strength and weakness. Intuitively, combining multiple methods is one solution to get the optimal classification results. In this paper, by generalizing the concept of the large margin nearest neighbor (LMNN), a method for combining multiple distance metrics from different types of protein structure comparison methods for protein fold classification task is proposed. While LMNN is limited to Mahalanobis-based distance metric learning from a set of feature vectors of training data, the proposed method learns an optimal combination of metrics from a set of distance metrics by minimizing the distances between intra-class data and enlarging the distances of different classes' data. The main advantage of the proposed method is the capability in finding an optimal weight coefficient for combination of many metrics, possibly including poor metrics, avoiding the difficulties in selecting which metrics to be included for the combination. The effectiveness of the proposed method is demonstrated on classification experiments using two public protein datasets, namely, Ding Dubchak dataset and ENZYMES dataset.

  • Analysis of Oversampling Effect on Selected Mapping Scheme Using CORR Metric

    Jun-Young WOO  Kee-Hoon KIM  Kang-Seok LEE  Jong-Seon NO  Dong-Joon SHIN  

     
    PAPER-Transmission Systems and Transmission Equipment for Communications

      Vol:
    E99-B No:2
      Page(s):
    364-369

    It is known that in the selected mapping (SLM) scheme for orthogonal frequency division multiplexing (OFDM), correlation (CORR) metric outperforms the peak-to-average power ratio (PAPR) metric in terms of bit error rate (BER) performance. It is also well known that four times oversampling is used for estimating the PAPR performance of continuous OFDM signal. In this paper, the oversampling effect of OFDM signal is analyzed when CORR metric is used for the SLM scheme in the presence of nonlinear high power amplifier. An analysis based on the correlation coefficients of the oversampled OFDM signals shows that CORR metric of two times oversampling in the SLM scheme is good enough to achieve the same BER performance as four times and 16 times oversampling cases. Simulation results confirm that for the SLM scheme using CORR metric, the BER performance for two times oversampling case is almost the same as that for four and 16 times oversampling cases.

  • Estimation of Interpersonal Relationships in Movies

    Yuta OHWATARI  Takahiro KAWAMURA  Yuichi SEI  Yasuyuki TAHARA  Akihiko OHSUGA  

     
    PAPER

      Pubricized:
    2015/11/05
      Vol:
    E99-D No:1
      Page(s):
    128-137

    In many movies, social conditions and awareness of the issues of the times are depicted in any form. Even if fantasy and science fiction are works far from reality, the character relationship does mirror the real world. Therefore, we try to understand social conditions of the real world by analyzing the movie. As a way to analyze the movies, we propose a method of estimating interpersonal relationships of the characters, using a machine learning technique called Markov Logic Network (MLN) from movie script databases on the Web. The MLN is a probabilistic logic network that can describe the relationships between characters, which are not necessarily satisfied on every line. In experiments, we confirmed that our proposed method can estimate favors between the characters in a movie with F-measure of 58.7%. Finally, by comparing the relationships with social indicators, we discussed the relevance of the movies to the real world.

  • Towards Position-Aware Symbol-Based Searches on Encrypted Data from Symmetric Predicate Encryption Schemes

    Fu-Kuo TSENG  Rong-Jaye CHEN  

     
    LETTER-Cryptography and Information Security

      Vol:
    E99-A No:1
      Page(s):
    426-428

    Symmetric predicate encryption schemes support a rich class of predicates over keyword ciphertexts while preserving both keyword privacy and predicate privacy. Most of these schemes treat each keyword as the smallest unit to be processed in the generation of ciphertexts and predicate tokens. To extend the class of predicates, we treat each symbol of a keyword as the smallest unit to be processed. In this letter, we propose a novel encoding to construct a symmetric inner-product encryption scheme for position-aware symbol-based predicates. The resulting scheme can be applied to a number of secure filtering and online storage services.

  • Unitary Transform-Based Template Protection and Its Application to l2-norm Minimization Problems

    Ibuki NAKAMURA  Yoshihide TONOMURA  Hitoshi KIYA  

     
    PAPER

      Pubricized:
    2015/10/21
      Vol:
    E99-D No:1
      Page(s):
    60-68

    We focus on the feature transform approach as one methodology for biometric template protection, where the template consists of the features extracted from the biometric trait. This study considers some properties of the unitary (including orthogonal) transform-based template protection in particular. It is known that the Euclidean distance between the templates protected by a unitary transform is the same as that between original (non-protected) ones as a property. In this study, moreover, it is shown that it provides the same results in l2-norm minimization problems as those of original templates. This means that there is no degradation of recognition performance in authentication systems using l2-norm minimization. Therefore, the protected templates can be reissued multiple times without original templates. In addition, a DFT-based template protection scheme is proposed as an unitary transform-based one. The proposed scheme enables to efficiently generate protected templates by the FFT, in addition to the useful properties. It is also applied to face recognition experiments to evaluate the effectiveness.

  • Amplified Redox Sensor for Highly Sensitive Chemical Analysis

    Sou TAKAHASHI  Masato FUTAGAWA  Makoto ISHIDA  Kazuaki SAWADA  

     
    PAPER-Electronic Circuits

      Vol:
    E99-C No:1
      Page(s):
    95-99

    Because redox sensors can detect multi-ions and the concentration within a single sensing area using current and potential signals, they have been studied for chemical analysis applications. A small sensing area and a low concentration measurement typically reduce the output current of a redox sensor. Therefore, we previously fabricated the Amplified Redox Sensor, which has a working electrode combined with a bipolar transistor to amplify a small current signal. However, the current gain of the bipolar transistor had been changed by the redox current because the redox current flows in the base terminal of the bipolar transistor. In this study, we propose a new measurement method in which an offset current is inserted along with the redox current in the base terminal. The proposed measurement method can detect potassium ferricyanide (K3[Fe (CN)6]) concentrations as low as 1μM using the Square Wave Voltammetry method.

  • Digital Halftoning through Approximate Optimization of Scale-Related Perceived Error Metric

    Zifen HE  Yinhui ZHANG  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2015/10/20
      Vol:
    E99-D No:1
      Page(s):
    305-308

    This work presents an approximate global optimization method for image halftone by fusing multi-scale information of the tree model. We employ Gaussian mixture model and hidden Markov tree to characterized the intra-scale clustering and inter-scale persistence properties of the detailed coefficients, respectively. The model of multiscale perceived error metric and the theory of scale-related perceived error metric are used to fuse the statistical distribution of the error metric of the scale of clustering and cross-scale persistence. An Energy function is then generated. Through energy minimization via graph cuts, we gain the halftone image. In the related experiment, we demonstrate the superior performance of this new algorithm when compared with several algorithms and quantitative evaluation.

  • Practical Forgeries and Distinguishers against PAES

    Jérémy JEAN  Ivica NIKOLIC  Yu SASAKI  Lei WANG  

     
    PAPER

      Vol:
    E99-A No:1
      Page(s):
    39-48

    We present two practical attacks on the CAESAR candidate PAES. The first attack is a universal forgery for any plaintext with at least 240 bytes. It works for the nonce-repeating variant of PAES and in a nutshell it is a state recovery based on solving differential equations for the S-Box leaked through the ciphertext that arise when the plaintext has a certain difference. We show that to produce the forgery based on this method the attacker needs only 211 time and data. The second attack is a distinguisher for 264 out of 2128 keys that requires negligible complexity and only one pair of known plaintext-ciphertext. The attack is based on the lack of constants in the initialization of the PAES which allows to exploit the symmetric properties of the keyless AES round. Both of our attacks contradict the security goals of PAES.

  • Rate-Distortion Performance of Convolutional Codes for Binary Symmetric Source

    Yohei ONISHI  Hidaka KINUGASA  Takashi MURAKI  Motohiko ISAKA  

     
    LETTER-Coding Theory

      Vol:
    E98-A No:12
      Page(s):
    2480-2482

    We present numerical results on the rate-distortion performance of convolutional coding for the binary symmetric source, and show how convolutional codes approach the rate-distortion bound by increasing the trellis states.

  • Supervised SOM Based ATR Method with Circular Polarization Basis of Full Polarimetric Data

    Shouhei OHNO  Shouhei KIDERA  Tetsuo KIRIMOTO  

     
    PAPER-Sensing

      Vol:
    E98-B No:12
      Page(s):
    2520-2527

    Satellite-borne or aircraft-borne synthetic aperture radar (SAR) is useful for high resolution imaging analysis for terrain surface monitoring or surveillance, particularly in optically harsh environments. For surveillance application, there are various approaches for automatic target recognition (ATR) of SAR images aiming at monitoring unidentified ships or aircraft. In addition, various types of analyses for full polarimetric data have been developed recently because it can provide significant information to identify structure of targets, such as vegetation, urban, sea surface areas. ATR generally consists of two processes, one is target feature extraction including target area determination, and the other is classification. In this paper, we propose novel methods for these two processes that suit full polarimetric exploitation. As the target area extraction method, we introduce a peak signal-to noise ratio (PSNR) based synthesis with full polarimetric SAR images. As the classification method, the circular polarization basis conversion is adopted to improve the robustness especially to variation of target rotation angles. Experiments on a 1/100 scale model of X-band SAR, demonstrate that our proposed method significantly improves the accuracy of target area extraction and classification, even in noisy or target rotating situations.

  • Lines of Comments as a Noteworthy Metric for Analyzing Fault-Proneness in Methods

    Hirohisa AMAN  Sousuke AMASAKI  Takashi SASAKI  Minoru KAWAHARA  

     
    PAPER-Software Engineering

      Pubricized:
    2015/09/04
      Vol:
    E98-D No:12
      Page(s):
    2218-2228

    This paper focuses on the power of comments to predict fault-prone programs. In general, comments along with executable statements enhance the understandability of programs. However, comments may also be used to mask the lack of readability in the program, therefore well-written comments are referred to as “deodorant to mask code smells” in the field of code refactoring. This paper conducts an empirical analysis to examine whether Lines of Comments (LCM) written inside a method's body is a noteworthy metric for analyzing fault-proneness in Java methods. The empirical results show the following two findings: (1) more-commented methods (the methods having more comments than the amount estimated by size and complexity of the methods) are about 1.6 - 2.8 times more likely to be faulty than the others, and (2) LCM can be a useful factor in fault-prone method prediction models along with the method size and the method complexity.

  • Almost Sure Convergence Coding Theorems of One-Shot and Multi-Shot Tunstall Codes for Stationary Memoryless Sources

    Mitsuharu ARIMURA  

     
    PAPER-Source Coding

      Vol:
    E98-A No:12
      Page(s):
    2393-2406

    Almost sure convergence coding theorems of one-shot and multi-shot Tunstall codes are proved for stationary memoryless sources. Coding theorem of one-shot Tunstall code is proved in the case that the leaf count of Tunstall tree increases. On the other hand, coding theorem is proved for multi-shot Tunstall code with increasing parsing count, under the assumption that the Tunstall tree grows as the parsing proceeds. In this result, it is clarified that the theorem for the one-shot Tunstall code is not a corollary of the theorem for the multi-shot Tunstall code. In the case of the multi-shot Tunstall code, it can be regarded that the coding theorem is proved for the sequential algorithm such that parsing and coding are processed repeatedly. Cartesian concatenation of trees and geometric mean of the leaf counts of trees are newly introduced, which play crucial roles in the analyses of multi-shot Tunstall code.

  • Unsupervised Weight Parameter Estimation for Exponential Mixture Distribution Based on Symmetric Kullback-Leibler Divergence

    Masato UCHIDA  

     
    LETTER-Information Theory

      Vol:
    E98-A No:11
      Page(s):
    2349-2353

    When there are multiple component predictors, it is promising to integrate them into one predictor for advanced reasoning. If each component predictor is given as a stochastic model in the form of probability distribution, an exponential mixture of the component probability distributions provides a good way to integrate them. However, weight parameters used in the exponential mixture model are difficult to estimate if there is no training samples for performance evaluation. As a suboptimal way to solve this problem, weight parameters may be estimated so that the exponential mixture model should be a balance point that is defined as an equilibrium point with respect to the distance from/to all component probability distributions. In this paper, we propose a weight parameter estimation method that represents this concept using a symmetric Kullback-Leibler divergence and generalize this method.

  • Biometric Identification Using JPEG2000 Compressed ECG Signals

    Hung-Tsai WU  Yi-Ting WU  Wen-Whei CHANG  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2015/06/24
      Vol:
    E98-D No:10
      Page(s):
    1829-1837

    In wireless telecardiology applications, electrocardiogram (ECG) signals are often represented in compressed format for efficient transmission and storage purposes. Incorporation of compressed ECG based biometric enables faster person identification as it by-passes the full decompression. This study presents a new method to combine ECG biometrics with data compression within a common JPEG2000 framework. To this end, an ECG signal is considered as an image and the JPEG2000 standard is applied for data compression. Features relating to ECG morphology and heartbeat intervals are computed directly from the compressed ECG. Different classification approaches are used for person identification. Experiments on standard ECG databases demonstrate the validity of the proposed system for biometric identification with high accuracies on both healthy and diseased subjects.

  • Software Reliability Assessment via Non-Parametric Maximum Likelihood Estimation

    Yasuhiro SAITO  Tadashi DOHI  

     
    PAPER

      Vol:
    E98-A No:10
      Page(s):
    2042-2050

    In this paper we consider two non-parametric estimation methods for software reliability assessment without specifying the fault-detection time distribution, where the underlying stochastic process to describe software fault-counts in the system testing is given by a non-homogeneous Poisson process. The resulting data-driven methodologies can give the useful probabilistic information on the software reliability assessment under the incomplete knowledge on fault-detection time distribution. Throughout examples with real software fault data, it is shown that the proposed methods provide more accurate estimation results than the common parametric approach.

  • Software Reliability Modeling Based on Burr XII Distributions

    Takahiro IMANAKA  Tadashi DOHI  

     
    LETTER

      Vol:
    E98-A No:10
      Page(s):
    2091-2095

    In this letter we develop a software reliability modeling framework by introducing the Burr XII distributions to software fault-detection time. An extension to deal with software metrics data characterizing the product size, program complexity or testing expenditure is also proposed. Finally, we investigate the goodness-of-fit performance and compare our new models with the existing ones through real data analyses.

141-160hit(675hit)