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4161-4180hit(16314hit)

  • QoS Analysis for Service Composition by Human and Web Services Open Access

    Donghui LIN  Toru ISHIDA  Yohei MURAKAMI  Masahiro TANAKA  

     
    PAPER

      Vol:
    E97-D No:4
      Page(s):
    762-769

    The availability of more and more Web services provides great varieties for users to design service processes. However, there are situations that services or service processes cannot meet users' requirements in functional QoS dimensions (e.g., translation quality in a machine translation service). In those cases, composing Web services and human tasks is expected to be a possible alternative solution. However, analysis of such practical efforts were rarely reported in previous researches, most of which focus on the technology of embedding human tasks in software environments. Therefore, this study aims at analyzing the effects of composing Web services and human activities using a case study in the domain of language service with large scale experiments. From the experiments and analysis, we find out that (1) service implementation variety can be greatly increased by composing Web services and human activities for satisfying users' QoS requirements; (2) functional QoS of a Web service can be significantly improved by inducing human activities with limited cost and execution time provided certain quality of human activities; and (3) multiple QoS attributes of a composite service are affected in different ways with different quality of human activities.

  • Microphone Classification Using Canonical Correlation Analysis

    Jongwon SEOK  Keunsung BAE  

     
    LETTER-Multimedia Environment Technology

      Vol:
    E97-A No:4
      Page(s):
    1024-1026

    Canonical correlation analysis (CCA) is applied to extract features for microphone classification. We utilized the coherence between near-silence regions. Experimental results show the promise of canonical correlation features for microphone classification.

  • An Efficient Beamforming Algorithm for Large-Scale Phased Arrays with Lossy Digital Phase Shifters

    Shunji TANAKA  Tomohiko MITANI  Yoshio EBIHARA  

     
    PAPER-Antennas and Propagation

      Vol:
    E97-B No:4
      Page(s):
    783-790

    An efficient beamforming algorithm for large-scale phased arrays with lossy digital phase shifters is presented. This problem, which arises in microwave power transmission from solar power satellites, is to maximize the array gain in a desired direction with the gain loss of the phase shifters taken into account. In this paper the problem is first formulated as a discrete optimization problem, which is then decomposed into element-wise subproblems by the real rotation theorem. Based on this approach, a polynomial-time algorithm to solve the problem numerically is constructed and its effectiveness is verified by numerical simulations.

  • Mapping Articulatory-Features to Vocal-Tract Parameters for Voice Conversion

    Narpendyah Wisjnu ARIWARDHANI  Masashi KIMURA  Yurie IRIBE  Kouichi KATSURADA  Tsuneo NITTA  

     
    PAPER-Speech and Hearing

      Vol:
    E97-D No:4
      Page(s):
    911-918

    In this paper, we propose voice conversion (VC) based on articulatory features (AF) to vocal-tract parameters (VTP) mapping. An artificial neural network (ANN) is applied to map AF to VTP and to convert a speaker's voice to a target-speaker's voice. The proposed system is not only text-independent VC, in which it does not need parallel utterances between source and target-speakers, but can also be used for an arbitrary source-speaker. This means that our approach does not require source-speaker data to build the VC model. We are also focusing on a small number of target-speaker training data. For comparison, a baseline system based on Gaussian mixture model (GMM) approach is conducted. The experimental results for a small number of training data show that the converted voice of our approach is intelligible and has speaker individuality of the target-speaker.

  • Facial Expression Recognition Based on Facial Region Segmentation and Modal Value Approach

    Gibran BENITEZ-GARCIA  Gabriel SANCHEZ-PEREZ  Hector PEREZ-MEANA  Keita TAKAHASHI  Masahide KANEKO  

     
    PAPER-Image Recognition, Computer Vision

      Vol:
    E97-D No:4
      Page(s):
    928-935

    This paper presents a facial expression recognition algorithm based on segmentation of a face image into four facial regions (eyes-eyebrows, forehead, mouth and nose). In order to unify the different results obtained from facial region combinations, a modal value approach that employs the most frequent decision of the classifiers is proposed. The robustness of the algorithm is also evaluated under partial occlusion, using four different types of occlusion (half left/right, eyes and mouth occlusion). The proposed method employs sub-block eigenphases algorithm that uses the phase spectrum and principal component analysis (PCA) for feature vector estimation which is fed to a support vector machine (SVM) for classification. Experimental results show that using modal value approach improves the average recognition rate achieving more than 90% and the performance can be kept high even in the case of partial occlusion by excluding occluded parts in the feature extraction process.

  • Parameterized Multisurface Fitting for Multi-Frame Superresolution

    Hongliang XU  Fei ZHOU  Fan YANG  Qingmin LIAO  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E97-D No:4
      Page(s):
    1001-1003

    We propose a parameterized multisurface fitting method for multi-frame super-resolution (SR) processing. A parameter assumed for the unknown high-resolution (HR) pixel is used for multisurface fitting. Each surface fitted at each low-resolution (LR) pixel is an expression of the parameter. Final SR result is obtained by fusing the sampling values from these surfaces in the maximum a posteriori fashion. Experimental results demonstrate the superiority of the proposed method.

  • Predicting Political Orientation of News Articles Based on User Behavior Analysis in Social Network Open Access

    Jun-Gil KIM  Kyung-Soon LEE  

     
    PAPER

      Vol:
    E97-D No:4
      Page(s):
    685-693

    News articles usually represent a biased viewpoint on contentious issues, potentially causing social problems. To mitigate this media bias, we propose a novel framework for predicting orientation of a news article by analyzing social user behaviors in Twitter. Highly active users tend to have consistent behavior patterns in social network by retweeting behavior among users with the same viewpoints for contentious issues. The bias ratio of highly active users is measured to predict orientation of users. Then political orientation of a news article is predicted based on the bias ratio of users, mutual retweeting and opinion analysis of tweet documents. The analysis of user behavior shows that users with the value of 1 in bias ratio are 88.82%. It indicates that most of users have distinctive orientation. Our prediction method based on orientation of users achieved 88.6% performance in accuracy. Experimental results show significant improvements over the SVM classification. These results show that proposed detection method is effective in social network.

  • A Framework to Integrate Public Information into Runtime Safety Analysis for Critical Systems

    Guoqi LI  

     
    LETTER-Dependable Computing

      Vol:
    E97-D No:4
      Page(s):
    981-983

    The large and complicated safety-critical systems today need to keep changing to accommodate ever-changing objectives and environments. Accordingly, runtime analysis for safe reconfiguration or evaluation is currently a hot topic in the field, whereas information acquisition of external environment is crucial for runtime safety analysis. With the rapid development of web services, mobile networks and ubiquitous computing, abundant realtime information of environment is available on the Internet. To integrate these public information into runtime safety analysis of critical systems, this paper brings forward a framework, which could be implemented with open source and cross platform modules and encouragingly, applicable to various safety-critical systems.

  • A Secure and Efficient Certificateless Aggregate Signature Scheme

    He LIU  Mangui LIANG  Haoliang SUN  

     
    LETTER-Cryptography and Information Security

      Vol:
    E97-A No:4
      Page(s):
    991-995

    In this letter, we propose a new secure and efficient certificateless aggregate signature scheme which has the advantages of both certificateless public key cryptosystem and aggregate signature. Based on the computational Diffie-Hellman problem, our scheme can be proven existentially unforgeable against adaptive chosen-message attacks. Most importantly, our scheme requires short group elements for aggregate signature and constant pairing computations for aggregate verification, which leads to high efficiency due to no relations with the number of signers.

  • Negative Surveys with Randomized Response Techniques for Privacy-Aware Participatory Sensing

    Shunsuke AOKI  Kaoru SEZAKI  

     
    PAPER-Network

      Vol:
    E97-B No:4
      Page(s):
    721-729

    Participatory sensing is an emerging system that allows the increasing number of smartphone users to share effectively the minute statistical information collected by themselves. This system relies on participants' active contribution including intentional input data. However, a number of privacy concerns will hinder the spread of participatory sensing applications. It is difficult for resource-constrained mobile phones to rely on complicated encryption schemes. We should prepare a privacy-preserving participatory sensing scheme with low computation complexity. Moreover, an environment that can reassure participants and encourage their participation in participatory sensing is strongly required because the quality of the statistical data is dependent on the active contribution of general users. In this article, we present MNS-RRT algorithms, which is the combination of negative surveys and randomized response techniques, for preserving privacy in participatory sensing, with high levels of data integrity. By using our method, participatory sensing applications can deal with a data having two selections in a dimension. We evaluated how this scheme can preserve the privacy while ensuring data integrity.

  • Compressive Sensing of Audio Signal via Structured Shrinkage Operators

    Sumxin JIANG  Rendong YING  Peilin LIU  Zhenqi LU  Zenghui ZHANG  

     
    PAPER-Digital Signal Processing

      Vol:
    E97-A No:4
      Page(s):
    923-930

    This paper describes a new method for lossy audio signal compression via compressive sensing (CS). In this method, a structured shrinkage operator is employed to decompose the audio signal into three layers, with two sparse layers, tonal and transient, and additive noise, and then, both the tonal and transient layers are compressed using CS. Since the shrinkage operator is able to take into account the structure information of the coefficients in the transform domain, it is able to achieve a better sparse approximation of the audio signal than traditional methods do. In addition, we propose a sparsity allocation algorithm, which adjusts the sparsity between the two layers, thus improving the performance of CS. Experimental results demonstrated that the new method provided a better compression performance than conventional methods did.

  • An Automated Segmentation Algorithm for CT Volumes of Livers with Atypical Shapes and Large Pathological Lesions

    Shun UMETSU  Akinobu SHIMIZU  Hidefumi WATANABE  Hidefumi KOBATAKE  Shigeru NAWANO  

     
    PAPER-Biological Engineering

      Vol:
    E97-D No:4
      Page(s):
    951-963

    This paper presents a novel liver segmentation algorithm that achieves higher performance than conventional algorithms in the segmentation of cases with unusual liver shapes and/or large liver lesions. An L1 norm was introduced to the mean squared difference to find the most relevant cases with an input case from a training dataset. A patient-specific probabilistic atlas was generated from the retrieved cases to compensate for livers with unusual shapes, which accounts for liver shape more specifically than a conventional probabilistic atlas that is averaged over a number of training cases. To make the above process robust against large pathological lesions, we incorporated a novel term based on a set of “lesion bases” proposed in this study that account for the differences from normal liver parenchyma. Subsequently, the patient-specific probabilistic atlas was forwarded to a graph-cuts-based fine segmentation step, in which a penalty function was computed from the probabilistic atlas. A leave-one-out test using clinical abdominal CT volumes was conducted to validate the performance, and proved that the proposed segmentation algorithm with the proposed patient-specific atlas reinforced by the lesion bases outperformed the conventional algorithm with a statistically significant difference.

  • Some Results on Generalized Quasi-Cyclic Codes over $mathbb{F}_q+umathbb{F}_q$

    Jian GAO  Fang-Wei FU  Linzhi SHEN  Wenli REN  

     
    LETTER-Coding Theory

      Vol:
    E97-A No:4
      Page(s):
    1005-1011

    Generalized quasi-cyclic (GQC) codes with arbitrary lengths over the ring $mathbb{F}_{q}+umathbb{F}_{q}$, where u2=0, q=pn, n a positive integer and p a prime number, are investigated. By the Chinese Remainder Theorem, structural properties and the decomposition of GQC codes are given. For 1-generator GQC codes, minimum generating sets and lower bounds on the minimum distance are given.

  • Asymptotic Marginal Likelihood on Linear Dynamical Systems

    Takuto NAITO  Keisuke YAMAZAKI  

     
    PAPER-Artificial Intelligence, Data Mining

      Vol:
    E97-D No:4
      Page(s):
    884-892

    Linear dynamical systems are basic state space models literally dealing with underlying system dynamics on the basis of linear state space equations. When the model is employed for time-series data analysis, the system identification, which detects the dimension of hidden state variables, is one of the most important tasks. Recently, it has been found that the model has singularities in the parameter space, which implies that analysis for adverse effects of the singularities is necessary for precise identification. However, the singularities in the models have not been thoroughly studied. There is a previous work, which dealt with the simplest case; the hidden state and the observation variables are both one dimensional. The present paper extends the setting to general dimensions and more rigorously reveals the structure of singularities. The results provide the asymptotic forms of the generalization error and the marginal likelihood, which are often used as criteria for the system identification.

  • Joint CPFSK Modulation and Physical-Layer Network Coding in Two-Way Relay Channels

    Nan SHA  Yuanyuan GAO  Xiaoxin YI  Wenlong LI  Weiwei YANG  

     
    LETTER-Communication Theory and Signals

      Vol:
    E97-A No:4
      Page(s):
    1021-1023

    A joint continuous phase frequency shift keying (CPFSK) modulation and physical-layer network coding (PNC), i.e., CPFSK-PNC, is proposed for two-way relay channels (TWRCs). This letter discusses the signal detection of the CPFSK-PNC scheme with emphasis on the maximum-likelihood sequence detection (MLSD) algorithm for the relay receiver. The end-to-end error performance of the proposed CPFSK-PNC scheme is evaluated through simulations.

  • Computationally Efficient Estimation of Squared-Loss Mutual Information with Multiplicative Kernel Models

    Tomoya SAKAI  Masashi SUGIYAMA  

     
    LETTER-Fundamentals of Information Systems

      Vol:
    E97-D No:4
      Page(s):
    968-971

    Squared-loss mutual information (SMI) is a robust measure of the statistical dependence between random variables. The sample-based SMI approximator called least-squares mutual information (LSMI) was demonstrated to be useful in performing various machine learning tasks such as dimension reduction, clustering, and causal inference. The original LSMI approximates the pointwise mutual information by using the kernel model, which is a linear combination of kernel basis functions located on paired data samples. Although LSMI was proved to achieve the optimal approximation accuracy asymptotically, its approximation capability is limited when the sample size is small due to an insufficient number of kernel basis functions. Increasing the number of kernel basis functions can mitigate this weakness, but a naive implementation of this idea significantly increases the computation costs. In this article, we show that the computational complexity of LSMI with the multiplicative kernel model, which locates kernel basis functions on unpaired data samples and thus the number of kernel basis functions is the sample size squared, is the same as that for the plain kernel model. We experimentally demonstrate that LSMI with the multiplicative kernel model is more accurate than that with plain kernel models in small sample cases, with only mild increase in computation time.

  • Single-Grain Si Thin-Film Transistors for Monolithic 3D-ICs and Flexible Electronics Open Access

    Ryoichi ISHIHARA  Jin ZHANG  Miki TRIFUNOVIC  Jaber DERAKHSHANDEH  Negin GOLSHANI  Daniel M. R. TAJARI MOFRAD  Tao CHEN  Kees BEENAKKER  Tatsuya SHIMODA  

     
    INVITED PAPER

      Vol:
    E97-C No:4
      Page(s):
    227-237

    We review our recent achievements in monolithic 3D-ICs and flexible electronics based on single-grain Si TFTs that are fabricated inside a single-grain with a low-temperature process. Based on pulsed-laser crystallization and submicron sized cavities made in the substrate, amorphous-Si precursor film was converted into poly-Si having grains that are formed on predetermined positions. Using the method called µ-Czochralski process and LPCVD a-Si precursor film, two layers of the SG Si TFT layers with the grains having a diameter of 6µm were vertically stacked with a maximum process temperature of 550°C. Mobility for electrons and holes were 600cm2/Vs and 200cm2/Vs, respectively. As a demonstration of monolithic 3D-ICs, the two SG-TFT layers were successfully implemented into CMOS inverter, 3D 6T-SRAM and single-grain lateral PIN photo-diode with in-pixel amplifier. The SG Si TFTs were applied to flexible electronics. In this case, the a-Si precursor was prepared by doctor-blade coating of liquid-Si based on pure cyclopentasilane (CPS) on a polyimide (PI) substrate with maximum process temperature of 350°C. The µ-Czochralski process provided location-controlled Si grains with a diameter of 3µm and mobilities of 460 and 121cm2/Vs for electrons and holes, respectively, were obtained. The devices on PI were transferred to a plastic foil which can operate with a bending diameter of 6mm. Those results indicate that the SG TFTs are attractive for their use in both monolithic 3D-ICs and flexible electronics.

  • Sentiment Classification in Under-Resourced Languages Using Graph-Based Semi-Supervised Learning Methods Open Access

    Yong REN  Nobuhiro KAJI  Naoki YOSHINAGA  Masaru KITSUREGAWA  

     
    PAPER

      Vol:
    E97-D No:4
      Page(s):
    790-797

    In sentiment classification, conventional supervised approaches heavily rely on a large amount of linguistic resources, which are costly to obtain for under-resourced languages. To overcome this scarce resource problem, there exist several methods that exploit graph-based semi-supervised learning (SSL). However, fundamental issues such as controlling label propagation, choosing the initial seeds, selecting edges have barely been studied. Our evaluation on three real datasets demonstrates that manipulating the label propagating behavior and choosing labeled seeds appropriately play a critical role in adopting graph-based SSL approaches for this task.

  • A Two-Stage Classifier That Identifies Charge and Punishment under Criminal Law of Civil Law System

    Sotarat THAMMABOOSADEE  Bunthit WATANAPA  Jonathan H. CHAN  Udom SILPARCHA  

     
    PAPER-Artificial Intelligence, Data Mining

      Vol:
    E97-D No:4
      Page(s):
    864-875

    A two-stage classifier is proposed that identifies criminal charges and a range of punishments given a set of case facts and attributes. Our supervised-learning model focuses only on the offences against life and body section of the criminal law code of Thailand. The first stage identifies a set of diagnostic issues from the case facts using a set of artificial neural networks (ANNs) modularized in hierarchical order. The second stage extracts a set of legal elements from the diagnostic issues by employing a set of C4.5 decision tree classifiers. These linked modular networks of ANNs and decision trees form an effective system in terms of determining power and the ability to trace or infer the relevant legal reasoning behind the determination. Isolated and system-integrated experiments are conducted to measure the performance of the proposed system. The overall accuracy of the integrated system can exceed 90%. An actual case is also demonstrated to show the effectiveness of the proposed system.

  • Finding Small Fundamental Instantons of LDPC Codes by Path Extension

    Junjun GUO  Jianjun MU  Xiaopeng JIAO  Guiping LI  

     
    LETTER-Coding Theory

      Vol:
    E97-A No:4
      Page(s):
    1001-1004

    In this letter, we present a new scheme to find small fundamental instantons (SFIs) of regular low-density parity-check (LDPC) codes for the linear programming (LP) decoding over the binary symmetric channel (BSC). Based on the fact that each instanton-induced graph (IIG) contains at least one short cycle, we determine potential instantons by constructing possible IIGs which contain short cycles and additional paths connected to the cycles. Then we identify actual instantons from potential ones under the LP decoding. Simulation results on some typical LDPC codes show that our scheme is effective, and more instantons can be obtained by the proposed scheme when compared with the existing instanton search method.

4161-4180hit(16314hit)