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  • 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.

  • Part-Segment Features with Optimized Shape Priors for Articulated Pose Estimation

    Norimichi UKITA  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2015/10/14
      Vol:
    E99-D No:1
      Page(s):
    248-256

    We propose part-segment (PS) features for estimating an articulated pose in still images. The PS feature evaluates the image likelihood of each body part (e.g. head, torso, and arms) robustly to background clutter and nuisance textures on the body. While general gradient features (e.g. HOG) might include many nuisance responses, the PS feature represents only the region of the body part by iterative segmentation while updating the shape prior of each part. In contrast to similar segmentation features, part segmentation is improved by part-specific shape priors that are optimized by training images with fully-automatically obtained seeds. The shape priors are modeled efficiently based on clustering for fast extraction of PS features. The PS feature is fused complementarily with gradient features using discriminative training and adaptive weighting for robust and accurate evaluation of part similarity. Comparative experiments with public datasets demonstrate improvement in pose estimation by the PS features.

  • Dynamic Rendering Quality Scaling Based on Resolution Changes

    MinKyu KIM  SunHo KI  YoungDuke SEO  JinHong PARK  ChuShik JHON  

     
    LETTER-Computer Graphics

      Pubricized:
    2015/09/17
      Vol:
    E98-D No:12
      Page(s):
    2353-2357

    Recently in the mobile graphic industry, ultra-realistic visual qualities with 60fps and limited power budget for GPU have been required. For graphics-heavy applications that run at 30 fps, we easily observed very noticeable flickering artifacts. Further, the workload imposed by high resolutions at high frame rates directly decreases the battery life. Unlike the recent frame rate up sampling algorithms which remedy the flickering but cause inevitable significant overheads to reconstruct intermediate frames, we propose a dynamic rendering quality scaling (DRQS) that includes dynamic rendering based on resolution changes and quality scaling to increase the frame rate with negligible overhead using a transform matrix. Further DRQS reduces the workload up to 32% without human visual-perceptual changes for graphics-light applications.

  • On Finding Secure Domain Parameters Resistant to Cheon's Algorithm

    SeongHan SHIN  Kazukuni KOBARA  Hideki IMAI  

     
    PAPER-Cryptography and Information Security

      Vol:
    E98-A No:12
      Page(s):
    2456-2470

    In the literature, many cryptosystems have been proposed to be secure under the Strong Diffie-Hellman (SDH) and related problems. For example, there is a cryptosystem that is based on the SDH/related problem or allows the Diffie-Hellman oracle. If the cryptosystem employs general domain parameters, this leads to a significant security loss caused by Cheon's algorithm [14], [15]. However, all elliptic curve domain parameters explicitly recommended in the standards (e.g., ANSI X9.62/63 [1], [2], FIPS PUB 186-4 [43], SEC 2 [50], [51]) are susceptible to Cheon's algorithm [14], [15]. In this paper, we first prove that (q-1)(q+1) is always divisible by 24 for any prime order q>3. Based on this result and depending on small divisors d1,d2≤(log q)2, we classify primes q>3, such that both (q-1)/d1 and (q+1)/d2 are primes, into Perfect, Semiperfect, SEC1v2 and Acceptable. Then, we describe algorithmic procedures and show their simulation results of secure elliptic curve domain parameters over prime/character 2 finite fields resistant to Cheon's algorithm [14], [15]. Also, several examples of the secure elliptic curve domain parameters (including Perfect or Semiperfect prime q) are followed.

  • A Decoding Algorithm for Cyclic Codes over Symbol-Pair Read Channels

    Makoto TAKITA  Masanori HIROTOMO  Masakatu MORII  

     
    PAPER-Coding Theory

      Vol:
    E98-A No:12
      Page(s):
    2415-2422

    Cassuto and Blaum presented a new coding framework for channels whose outputs are overlapping pairs of symbols in storage applications. Such channels are called symbol-pair read channels. Pair distance and pair error are used in symbol-pair read channels. Yaakobi et al. proved a lower bound on the minimum pair distance of cyclic codes. Furthermore, they provided a decoding algorithm for correcting pair errors using a decoder for cyclic codes, and showed the number of pair errors that can be corrected by their algorithm. However, their algorithm cannot correct all pair error vectors within half of the minimum pair distance. In this paper, we propose an efficient decoding algorithm for cyclic codes over symbol-pair read channels. It is based on the relationship between pair errors and syndromes. In addition, we show that the proposed algorithm can correct more pair errors than Yaakobi's algorithm.

  • The Error Exponent of Zero-Rate Multiterminal Hypothesis Testing for Sources with Common Information

    Makoto UEDA  Shigeaki KUZUOKA  

     
    PAPER-Shannon Theory

      Vol:
    E98-A No:12
      Page(s):
    2384-2392

    The multiterminal hypothesis testing problem with zero-rate constraint is considered. For this problem, an upper bound on the optimal error exponent is given by Shalaby and Papamarcou, provided that the positivity condition holds. Our contribution is to prove that Shalaby and Papamarcou's upper bound is valid under a weaker condition: (i) two remote observations have a common random variable in the sense of Gácks and Körner, and (ii) when the value of the common random variable is fixed, the conditional distribution of remaining random variables satisfies the positivity condition. Moreover, a generalization of the main result is also given.

  • A Matching Pursuit Generalized Approximate Message Passing Algorithm

    Yongjie LUO  Qun WAN  Guan GUI  Fumiyuki ADACHI  

     
    LETTER-Numerical Analysis and Optimization

      Vol:
    E98-A No:12
      Page(s):
    2723-2727

    This paper proposes a novel matching pursuit generalized approximate message passing (MPGAMP) algorithm which explores the support of sparse representation coefficients step by step, and estimates the mean and variance of non-zero elements at each step based on a generalized-approximate-message-passing-like scheme. In contrast to the classic message passing based algorithms and matching pursuit based algorithms, our proposed algorithm saves a lot of intermediate process memory, and does not calculate the inverse matrix. Numerical experiments show that MPGAMP algorithm can recover a sparse signal from compressed sensing measurements very well, and maintain good performance even for non-zero mean projection matrix and strong correlated projection matrix.

  • Evaluation of the Bayes Code from Viewpoints of the Distribution of Its Codeword Lengths

    Shota SAITO  Nozomi MIYA  Toshiyasu MATSUSHIMA  

     
    PAPER-Source Coding

      Vol:
    E98-A No:12
      Page(s):
    2407-2414

    This paper considers universal lossless variable-length source coding problem and investigates the Bayes code from viewpoints of the distribution of its codeword lengths. First, we show that the codeword lengths of the Bayes code satisfy the asymptotic normality. This study can be seen as the investigation on the asymptotic shape of the distribution of codeword lengths. Second, we show that the codeword lengths of the Bayes code satisfy the law of the iterated logarithm. This study can be seen as the investigation on the asymptotic end points of the distribution of codeword lengths. Moreover, the overflow probability, which represents the bottom of the distribution of codeword lengths, is studied for the Bayes code. We derive upper and lower bounds of the infimum of a threshold on the overflow probability under the condition that the overflow probability does not exceed ε∈(0,1). We also analyze the necessary and sufficient condition on a threshold for the overflow probability of the Bayes code to approach zero asymptotically.

  • Rapid Converging M-Max Partial Update Least Mean Square Algorithms with New Variable Step-Size Methods

    Jin LI-YOU  Ying-Ren CHIEN  Yu TSAO  

     
    PAPER-Digital Signal Processing

      Vol:
    E98-A No:12
      Page(s):
    2650-2657

    Determining an effective way to reduce computation complexity is an essential task for adaptive echo cancellation applications. Recently, a family of partial update (PU) adaptive algorithms has been proposed to effectively reduce computational complexity. However, because a PU algorithm updates only a portion of the weights of the adaptive filters, the rate of convergence is reduced. To address this issue, this paper proposes an enhanced switching-based variable step-size (ES-VSS) approach to the M-max PU least mean square (LMS) algorithm. The step-size is determined by the correlation between the error signals and their noise-free versions. Noise-free error signals are approximated according to the level of convergence achieved during the adaptation process. The approximation of the noise-free error signals switches among four modes, such that the resulting step-size is as close to its optimal value as possible. Simulation results show that when only a half of all taps are updated in a single iteration, the proposed method significantly enhances the convergence rate of the M-max PU LMS algorithm.

  • Signal Propagation Delay Model in Vertically Stacked Chips

    Nanako NIIOKA  Masayuki WATANABE  Masa-aki FUKASE  Masashi IMAI  Atsushi KUROKAWA  

     
    PAPER-Device and Circuit Modeling and Analysis

      Vol:
    E98-A No:12
      Page(s):
    2614-2624

    To design high quality three-dimensional integrated circuits (3-D ICs), the effect of process and design parameters on delay must be adequately understood. This paper presents an electrical circuit model of an entire structure in through silicon via (TSV) based 3-D ICs with a new equation for on-chip interconnect capacitance and then proposes an effective model for evaluating signal propagation delay in vertically stacked chips. All electrical parameter values can be calculated by the closed-form equations without a field solver. The delay model is constructed with the first- or second-order function of each parameter to the delay obtained from a typical structure. The results obtained by on-chip interconnect capacitance equations and delay model are in excellent agreement with those by a field solver and circuit simulator, respectively. We also show that the model is very useful for evaluating effects of the process and design parameters on vertical signal propagation delay such as the sensitivity and variability analysis.

  • Moiré Reduction Using Inflection Point and Color Variation in Digital Camera of No Optical Low Pass Filter

    Dae-Chul KIM  Wang-Jun KYUNG  Ho-Gun HA  Yeong-Ho HA  

     
    PAPER-Image Processing and Video Processing

      Pubricized:
    2015/09/10
      Vol:
    E98-D No:12
      Page(s):
    2290-2298

    The role of an optical low-pass filter (OLPF) in a digital still camera is to remove the high spatial frequencies that cause aliasing, thereby enhancing the image quality. However, this also causes some loss of detail. Yet, when an image is captured without the OLPF, moiré generally appears in the high spatial frequency region of the image. Accordingly, this paper presents a moiré reduction method that allows omission of the OLPF. Since most digital still cameras use a CCD or a CMOS with a Bayer pattern, moiré patterns and color artifacts are simultaneously induced by aliasing at high spatial frequencies. Therefore, in this study, moiré reduction is performed in both the luminance channel to remove the moiré patterns and the color channel to reduce color smearing. To detect the moiré patterns, the spatial frequency response (SFR) of the camera is first analyzed. The moiré regions are identified using patterns related to the SFR of the camera and then analyzed in the frequency domain. The moiré patterns are reduced by removing their frequency components, represented by the inflection point between the high-frequency and DC components in the moiré region. To reduce the color smearing, color changing regions are detected using the color variation ratios for the RGB channels and then corrected by multiplying with the average surrounding colors. Experiments confirm that the proposed method is able to reduce the moiré in both the luminance and color channels, while also preserving the detail.

  • Performance Enhancement of Cross-Talk Canceller for Four-Speaker System by Selective Speaker Operation

    Su-Jin CHOI  Jeong-Yong BOO  Ki-Jun KIM  Hochong PARK  

     
    LETTER-Speech and Hearing

      Pubricized:
    2015/08/25
      Vol:
    E98-D No:12
      Page(s):
    2341-2344

    We propose a method of enhancing the performance of a cross-talk canceller for a four-speaker system with respect to sweet spot size and ringing effect. For the large sweet spot of a cross-talk canceller, the speaker layout needs to be symmetrical to the listener's position. In addition, a ringing effect of the cross-talk canceller is reduced when many speakers are located close to each other. Based on these properties, the proposed method first selects the two speakers in a four-speaker system that are most symmetrical to the target listener's position and then adds the remaining speakers between these two to the final selection. By operating only these selected speakers, the proposed method enlarges the sweet spot size and reduces the ringing effect. We conducted objective and subjective evaluations and verified that the proposed method improves the performance of the cross-talk canceller compared to the conventional method.

  • Survivability Analysis of VM-Based Intrusion Tolerant Systems

    Junjun ZHENG  Hiroyuki OKAMURA  Tadashi DOHI  

     
    PAPER-Network

      Pubricized:
    2015/09/15
      Vol:
    E98-D No:12
      Page(s):
    2082-2090

    Survivability is the capability of a system to provide its services in a timely manner even after intrusion and compromise occur. In this paper, we focus on the quantitative analysis of survivability of virtual machine (VM) based intrusion tolerant system in the presence of Byzantine failures due to malicious attacks. Intrusion tolerant system has the ability of a system to continuously provide correct services even if the system is intruded. This paper introduces a scheme of the intrusion tolerant system with virtualization, and derives the success probability for one request by a Markov chain under the environment where VMs have been intruded due to a security hole by malicious attacks. Finally, in numerical experiments, we evaluate the performance of VM-based intrusion tolerant system from the viewpoint of survivability.

  • GA-MAP: An Error Tolerant Address Mapping Method in Data Center Networks Based on Improved Genetic Algorithm

    Gang DENG  Hong WANG  Zhenghu GONG  Lin CHEN  Xu ZHOU  

     
    PAPER-Network

      Pubricized:
    2015/09/15
      Vol:
    E98-D No:12
      Page(s):
    2071-2081

    Address configuration is a key problem in data center networks. The core issue of automatic address configuration is assigning logical addresses to the physical network according to a blueprint, namely logical-to-device ID mapping, which can be formulated as a graph isomorphic problem and is hard. Recently years, some work has been proposed for this problem, such as DAC and ETAC. DAC adopts a sub-graph isomorphic algorithm. By leveraging the structure characteristic of data center network, DAC can finish the mapping process quickly when there is no malfunction. However, in the presence of any malfunctions, DAC need human effort to correct these malfunctions and thus is time-consuming. ETAC improves on DAC and can finish mapping even in the presence of malfunctions. However, ETAC also suffers from some robustness and efficiency problems. In this paper, we present GA-MAP, a data center networks address mapping algorithm based on genetic algorithm. By intelligently leveraging the structure characteristic of data center networks and the global search characteristic of genetic algorithm, GA-MAP can solve the address mapping problem quickly. Moreover, GA-MAP can even finish address mapping when physical network involved in malfunctions, making it more robust than ETAC. We evaluate GA-MAP via extensive simulation in several of aspects, including computation time, error-tolerance, convergence characteristic and the influence of population size. The simulation results demonstrate that GA-MAP is effective for data center addresses mapping.

  • Development and Evaluation of Near Real-Time Automated System for Measuring Consumption of Seasonings

    Kazuaki NAKAMURA  Takuya FUNATOMI  Atsushi HASHIMOTO  Mayumi UEDA  Michihiko MINOH  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2015/09/07
      Vol:
    E98-D No:12
      Page(s):
    2229-2241

    The amount of seasonings used during food preparation is quite important information for modern people to enable them to cook delicious dishes as well as to take care for their health. In this paper, we propose a near real-time automated system for measuring and recording the amount of seasonings used during food preparation. Our proposed system is equipped with two devices: electronic scales and a camera. Seasoning bottles are basically placed on the electronic scales in the proposed system, and the scales continually measure the total weight of the bottles placed on them. When a chef uses a certain seasoning, he/she first picks up the bottle containing it from the scales, then adds the seasoning to a dish, and then returns the bottle to the scales. In this process, the chef's picking and returning actions are monitored by the camera. The consumed amount of each seasoning is calculated as the difference in weight between before and after it is used. We evaluated the performance of the proposed system with experiments in 301 trials in actual food preparation performed by seven participants. The results revealed that our system successfully measured the consumption of seasonings in 60.1% of all the trials.

  • Modeling and Testing of Network Protocols with Parallel State Machines

    Xia YIN  Jiangyuan YAO  Zhiliang WANG  Xingang SHI  Jun BI  Jianping WU  

     
    PAPER-Network

      Pubricized:
    2015/09/15
      Vol:
    E98-D No:12
      Page(s):
    2091-2104

    The researches on model-based testing mainly focus on the models with single component, such as FSM and EFSM. For the network protocols which have multiple components communicating with messages, CFSM is a widely accepted solution. But in some network protocols, parallel and data-shared components maybe exist in the same network entity. It is infeasible to precisely specify such protocol by existing models. In this paper we present a new model, Parallel Parameterized Extended Finite State Machine (PaP-EFSM). A protocol system can be modeled with a group of PaP-EFSMs. The PaP-EFSMs work in parallel and they can read external variables form each other. We present a 2-stage test generation approach for our new models. Firstly, we generate test sequences for internal variables of each machine. They may be non-executable due to external variables. Secondly, we process the external variables. We make the sequences for internal variables executable and generate more test sequences for external variables. For validation, we apply this method to the conformance testing of real-life protocols. The devices from different vendors are tested and implementation faults are exposed.

  • 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.

  • A Length Matching Routing Algorithm for Set-Pair Routing Problem

    Yuta NAKATANI  Atsushi TAKAHASHI  

     
    PAPER-Physical Level Design

      Vol:
    E98-A No:12
      Page(s):
    2565-2571

    In the routing design of interposer and etc., the combination of a pin pair to be connected by wire is often flexible, and the reductions of the total wire length and the length difference are pursued to keep the circuit performance. Even though the total wire length can be minimized by finding a minimum cost maximum flow in set pair routing problems, the length difference is often large, and the reduction of it is not easy. In this paper, an algorithm that reduces the length difference while keeping the total wire length small is proposed. In the proposed algorithm, an initial routing first obtained by a minimum cost maximum flow. Then it is modified to reduce the maximum length while keeping the minimum total wire length, and a connection of the minimum length is detoured to reduce the length difference. The effectiveness of the proposed algorithm is confirmed by experiments.

  • Design of CSD Coefficient FIR Filters Using PSO with Penalty Function

    Kazuki SAITO  Kenji SUYAMA  

     
    PAPER-Digital Signal Processing

      Vol:
    E98-A No:12
      Page(s):
    2625-2632

    In this paper, we propose a method for designing finite impulse response (FIR) filters with canonic signed digit (CSD) coefficients using particle swarm optimization (PSO). In such a design problem, a large number of local minimums appear in an evaluation function for the optimization. An updating procedure of PSO tends to stagnate around such local minimums and thus indicates a premature convergence property. Therefore, a new framework for avoiding such a situation is proposed, in which the evaluation function is modified around the stagnation point. Several design examples are shown to present the effectiveness of the proposed method.

  • Reduced-Reference Image Quality Assessment Based on Discrete Cosine Transform Entropy

    Yazhong ZHANG  Jinjian WU  Guangming SHI  Xuemei XIE  Yi NIU  Chunxiao FAN  

     
    PAPER-Digital Signal Processing

      Vol:
    E98-A No:12
      Page(s):
    2642-2649

    Reduced-reference (RR) image quality assessment (IQA) algorithm aims to automatically evaluate the distorted image quality with partial reference data. The goal of RR IQA metric is to achieve higher quality prediction accuracy using less reference information. In this paper, we introduce a new RR IQA metric by quantifying the difference of discrete cosine transform (DCT) entropy features between the reference and distorted images. Neurophysiological evidences indicate that the human visual system presents different sensitivities to different frequency bands. Moreover, distortions on different bands result in individual quality degradations. Therefore, we suggest to calculate the information degradation on each band separately for quality assessment. The information degradations are firstly measured by the entropy difference of reorganized DCT coefficients. Then, the entropy differences on all bands are pooled to obtain the quality score. Experimental results on LIVE, CSIQ, TID2008, Toyama and IVC databases show that the proposed method performs highly consistent with human perception with limited reference data (8 values).

4301-4320hit(20498hit)