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1601-1620hit(21534hit)

  • Deep Learning Approaches for Pathological Voice Detection Using Heterogeneous Parameters

    JiYeoun LEE  Hee-Jin CHOI  

     
    LETTER-Speech and Hearing

      Pubricized:
    2020/05/14
      Vol:
    E103-D No:8
      Page(s):
    1920-1923

    We propose a deep learning-based model for classifying pathological voices using a convolutional neural network and a feedforward neural network. The model uses combinations of heterogeneous parameters, including mel-frequency cepstral coefficients, linear predictive cepstral coefficients and higher-order statistics. We validate the accuracy of this model using the Massachusetts Eye and Ear Infirmary (MEEI) voice disorder database and the Saarbruecken Voice Database (SVD). Our model achieved an accuracy of 99.3% for MEEI and 75.18% for SVD. This model achieved an accuracy that is 7.18% higher than that of competitive models in previous studies.

  • A Reactive Reporting Scheme for Distributed Sensing in Multi-Band Wireless LAN System

    Rui TENG  Kazuto YANO  Yoshinori SUZUKI  

     
    PAPER-Wireless Communication Technologies

      Pubricized:
    2020/02/18
      Vol:
    E103-B No:8
      Page(s):
    860-871

    A multi-band wireless local area network (WLAN) enables flexible use of multiple frequency bands. To efficiently monitor radio resources in multi-band WLANs, a distributed-sensing system that employs a number of stations (STAs) is considered to alleviate sensing constraints at access points (APs). This paper examines the distributed sensing that expands the sensing coverage area and monitors multiple object channels by employing STA-based sensing. To avoid issuing unnecessary reports, each STA autonomously judges whether it should make a report by comparing the importance of its own sensing result and that of the overheard report. We address how to efficiently collect the necessary sensing information from a large number of STAs. We propose a reactive reporting scheme that is highly scalable by the number of STAs to collect such sensing results as the channel occupancy ratio. Evaluation results show that the proposed scheme keeps the number of reports low even if the number of STAs increases. Our proposed sensing scheme provides large sensing coverage.

  • Interference Management Using Beamforming Techniques for Line-of-Sight Femtocell Networks

    Khalid Sheikhidris MOHAMED  Mohamad Yusoff ALIAS  Mardeni ROSLEE  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Pubricized:
    2020/01/24
      Vol:
    E103-B No:8
      Page(s):
    881-887

    Femtocell structures can offer better voice and data exchange in cellular networks. However, interference in such networks poses a major challenge in the practical development of cellular communication. To tackle this issue, an advanced interference mitigation scheme for Line-Of-Sight (LOS) femtocell networks in indoor environments is proposed in this paper. Using a femtocell management system (FMS) that controls all femtocells in a service area, the aggressor femtocells are identified and then the transmitted beam patterns are adjusted using the linear array antenna equipped in each femtocell to mitigate the interference contribution to the neighbouring femtocells. Prior to that, the affected users are switched to the femtocells that provide better throughput levels to avoid increasing the outage probability. This paper considers different femtocell deployment indexes to verify and justifies the feasibility of the findings in different density areas. Relative to fixed and adaptive power control schemes, the proposed scheme achieves approximately 5% spectral efficiency (SE) improvement, about 10% outage probability reduction, and about 7% Mbps average user throughput improvement.

  • Lattice-Based Cryptanalysis of RSA with Implicitly Related Keys

    Mengce ZHENG  Noboru KUNIHIRO  Honggang HU  

     
    PAPER-Cryptography and Information Security

      Vol:
    E103-A No:8
      Page(s):
    959-968

    We address the security issue of RSA with implicitly related keys in this paper. Informally, we investigate under what condition is it possible to efficiently factorize RSA moduli in polynomial time given implicit relation of the related private keys that certain portions of bit pattern are the same. We formulate concrete attack scenarios and propose lattice-based cryptanalysis by using lattice reduction algorithms. A subtle lattice technique is adapted to represent an unknown private key with the help of known implicit relation. We analyze a simple case when given two RSA instances with the known amount of shared most significant bits (MSBs) and least significant bits (LSBs) of the private keys. We further extend to a generic lattice-based attack for given more RSA instances with implicitly related keys. Our theoretical results indicate that RSA with implicitly related keys is more insecure and better asymptotic results can be achieved as the number of RSA instances increases. Furthermore, we conduct numerical experiments to verify the validity of the proposed attacks.

  • Model Checking of Automotive Control Software: An Industrial Approach

    Masahiro MATSUBARA  Tatsuhiro TSUCHIYA  

     
    PAPER-Formal Approaches

      Pubricized:
    2020/03/30
      Vol:
    E103-D No:8
      Page(s):
    1794-1805

    In automotive control systems, the potential risks of software defects have been increasing due to growing software complexity driven by advances in electric-electronic control. Some kind of defects such as race conditions can rarely be detected by testing or simulations because these defects manifest themselves only in some rare executions. Model checking, which employs an exhaustive state-space exploration, is effective for detecting such defects. This paper reports our approach to applying model checking techniques to real-world automotive control programs. It is impossible to directly model check such programs because of their large size and high complexity; thus, it is necessary to derive, from the program under verification, a model that is amenable to model checking. Our approach uses the SPIN model checker as well as in-house tools that facilitate this process. One of the key features implemented in these tools is boundary-adjustable program slicing, which allows the user to specify and extract part of the source code that is relevant to the verification problem of interest. The conversion from extracted code into Promela, SPIN's input language, is performed using one of the tools in a semi-automatic manner. This approach has been used for several years in practice and found to be useful even when the code size of the software exceeds 400 KLOC.

  • Low Complexity Statistic Computation for Energy Detection Based Spectrum Sensing with Multiple Antennas

    Shusuke NARIEDA  Hiroshi NARUSE  

     
    PAPER-Communication Theory and Signals

      Vol:
    E103-A No:8
      Page(s):
    969-977

    This paper presents a novel statistic computation technique for energy detection-based spectrum sensing with multiple antennas. The presented technique computes the statistic for signal detection after combining all the signals. Because the computation of the statistic for all the received signals is not required, the presented technique reduces the computational complexity. Furthermore, the absolute value of all the received signals are combined to prevent the attenuation of the combined signals. Because the statistic computations are not required for all the received signals, the reduction of the computational complexity for signal detection can be expected. Furthermore, the presented technique does not need to choose anything, such as the binary phase rotator in the conventional technique, and therefore, the performance degradation due to wrong choices can be avoided. Numerical examples indicate that the spectrum sensing performances of the presented technique are almost the same as those of conventional techniques despite the complexity of the presented technique being less than that of the conventional techniques.

  • Spectrum Sensing with Selection Diversity Combining in Cognitive Radio

    Shusuke NARIEDA  Hiromichi OGASAWARA  Hiroshi NARUSE  

     
    PAPER-Communication Theory and Signals

      Vol:
    E103-A No:8
      Page(s):
    978-986

    This paper presents a novel spectrum sensing technique based on selection diversity combining in cognitive radio networks. In general, a selection diversity combining scheme requires a period to select an optimal element, and spectrum sensing requires a period to detect a target signal. We consider that both these periods are required for the spectrum sensing based on selection diversity combining. However, conventional techniques do not consider both the periods. Furthermore, spending a large amount of time in selection and signal detection increases their accuracy. Because the required period for spectrum sensing based on selection diversity combining is the summation of both the periods, their lengths should be considered while developing selection diversity combining based spectrum sensing for a constant period. In reference to this, we discuss the spectrum sensing technique based on selection diversity combining. Numerical examples are shown to validate the effectiveness of the presented design techniques.

  • Improvement of Pressure Control Skill with Knife Device for Paper-Cutting

    Takafumi HIGASHI  Hideaki KANAI  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2020/04/22
      Vol:
    E103-D No:8
      Page(s):
    1856-1864

    In this paper, we propose an interactive system for controlling the pressure while cutting paper with a knife. The purpose is to improve the cutting skill of novices learning the art of paper-cutting. Our system supports skill improvement for novices by measuring and evaluating their cutting pressure in real-time. In this study, we use a knife with a blade attached to a stylus with a pressure sensor, which can measure the pressure, coordinates, and cutting time. We have developed a similar support system using a stylus and a tablet device. This system allows the user to experience the pressure of experts through tracing. Paper-cutting is created by cutting paper with a knife. The practice system in this paper provides practice in an environment more akin to the production of paper cutting. In the first experiment, we observed differences in cutting ability by comparing cutting pressures between novices and experts. As a result, we confirmed that novices cut paper at a higher pressure than experts. We developed a practice system that guides the novices on controlling the pressure by providing information on the cutting pressure values of experts. This system shows the difference in pressure between novices and experts using a synchronous display of color and sound. Using these functions, novices learn to adjust their cutting pressure according to that of experts. Determining the right cutting pressure is a critical skill in the art of paper-cutting, and we aim to improve the same with our system. In the second experiment, we tested the effect of the practice system on the knife device. We compared the changes in cutting pressure with and without our system, the practice methods used in the workshop, and the previously developed stylus-based support system. As a result, we confirmed that practicing with the knife device had a better effect on the novice's skill in controlling cutting pressure than other practice methods.

  • A Novel Multi-Satellite Multi-Beam System with Single Frequency Reuse Applying MIMO

    Daisuke GOTO  Fumihiro YAMASHITA  

     
    PAPER-Antennas and Propagation

      Pubricized:
    2020/02/03
      Vol:
    E103-B No:8
      Page(s):
    842-851

    This paper introduces a new multi-satellite multi-beam system with single frequency reuse; it uses the MIMO (Multi Input Multi Output) technique to improve the frequency efficiency as the satellite communication band is limited. MIMO is the one of the most important approaches to improve the spectral efficiency in support of broadband communications. Since it is difficult to achieve high spectral efficiency by simply combining conventional MIMO satellite techniques, i.e. combining a multi-beam system with single frequency reuse with a multiple satellite system, this paper proposes transmitter pre-coding and receiver equalization techniques to enhance the channel capacity even under time/frequency asynchronous conditions. A channel capacity comparison shows that the proposed system is superior to conventional alternatives.

  • Highly Reliable Silica-LiNbO3 Hybrid Modulator Using Heterogeneous Material Integration Technology Open Access

    Atsushi ARATAKE  Ken TSUZUKI  Motohaya ISHII  Takashi SAIDA  Takashi GOH  Yoshiyuki DOI  Hiroshi YAMAZAKI  Takao FUKUMITSU  Takashi YAMADA  Shinji MINO  

     
    PAPER-Optoelectronics

      Pubricized:
    2020/02/13
      Vol:
    E103-C No:8
      Page(s):
    353-361

    Silica-LiNbO3 (LN) hybrid modulators have a hybrid configuration of versatile passive silica-based planar lightwave circuits (PLCs) and simple LN phase modulators arrays. By combining the advantages the two components, these hybrid modulators offer large-scale, highly-functionality modulators with low losses for advanced modulation formats. However, the reliability evaluation necessary to implement them in real transmissions has not been reported yet. In terms of reliability characteristics, there are issues originating from the difference in thermal expansion coefficients between silica PLC and LN. To resolve these issues, we propose design guidelines for hybrid modulators to mitigate the degradation induced by the thermal expansion difference. We fabricated several tens of silica-LN dual polarization quadrature phase shift keying (DP-QPSK) modulators based on the design guidelines and evaluated their reliability. The experiment results show that the modules have no degradation after a reliability test based on GR-468, which confirms the validity of the design guidelines for highly reliable silica-LN hybrid modulators. We can apply the guidelines for hybrid modules that realize heterogeneous device integration using materials with different coefficients of thermal expansion.

  • In-GPU Cache for Acceleration of Anomaly Detection in Blockchain

    Shin MORISHIMA  Hiroki MATSUTANI  

     
    PAPER-Computer System

      Pubricized:
    2020/04/28
      Vol:
    E103-D No:8
      Page(s):
    1814-1824

    Blockchain is a distributed ledger system composed of a P2P network and is used for a wide range of applications, such as international remittance, inter-individual transactions, and asset conservation. In Blockchain systems, tamper resistance is enhanced by the property of transaction that cannot be changed or deleted by everyone including the creator of the transaction. However, this property also becomes a problem that unintended transaction created by miss operation or secret key theft cannot be corrected later. Due to this problem, once an illegal transaction such as theft occurs, the damage will expand. To suppress the damage, we need countermeasures, such as detecting illegal transaction at high speed and correcting the transaction before approval. However, anomaly detection in the Blockchain at high speed is computationally heavy, because we need to repeat the detection process using various feature quantities and the feature extractions become overhead. In this paper, to accelerate anomaly detection, we propose to cache transaction information necessary for extracting feature in GPU device memory and perform both feature extraction and anomaly detection in the GPU. We also propose a conditional feature extraction method to reduce computation cost of anomaly detection. We employ anomaly detection using K-means algorithm based on the conditional features. When the number of users is one million and the number of transactions is 100 millions, our proposed method achieves 8.6 times faster than CPU processing method and 2.6 times faster than GPU processing method that does not perform feature extraction on the GPU. In addition, the conditional feature extraction method achieves 1.7 times faster than the unconditional method when the number of users satisfying a given condition is 200 thousands out of one million.

  • Knowledge Integration by Probabilistic Argumentation

    Saung Hnin Pwint OO  Nguyen Duy HUNG  Thanaruk THEERAMUNKONG  

     
    PAPER-Artificial Intelligence, Data Mining

      Pubricized:
    2020/05/01
      Vol:
    E103-D No:8
      Page(s):
    1843-1855

    While existing inference engines solved real world problems using probabilistic knowledge representation, one challenging task is to efficiently utilize the representation under a situation of uncertainty during conflict resolution. This paper presents a new approach to straightforwardly combine a rule-based system (RB) with a probabilistic graphical inference framework, i.e., naïve Bayesian network (BN), towards probabilistic argumentation via a so-called probabilistic assumption-based argumentation (PABA) framework. A rule-based system (RB) formalizes its rules into defeasible logic under the assumption-based argumentation (ABA) framework while the Bayesian network (BN) provides probabilistic reasoning. By knowledge integration, while the former provides a solid testbed for inference, the latter helps the former to solve persistent conflicts by setting an acceptance threshold. By experiments, effectiveness of this approach on conflict resolution is shown via an example of liver disorder diagnosis.

  • Machine Learning-Based Approach for Depression Detection in Twitter Using Content and Activity Features

    Hatoon S. ALSAGRI  Mourad YKHLEF  

     
    PAPER-Data Engineering, Web Information Systems

      Pubricized:
    2020/04/24
      Vol:
    E103-D No:8
      Page(s):
    1825-1832

    Social media channels, such as Facebook, Twitter, and Instagram, have altered our world forever. People are now increasingly connected than ever and reveal a sort of digital persona. Although social media certainly has several remarkable features, the demerits are undeniable as well. Recent studies have indicated a correlation between high usage of social media sites and increased depression. The present study aims to exploit machine learning techniques for detecting a probable depressed Twitter user based on both, his/her network behavior and tweets. For this purpose, we trained and tested classifiers to distinguish whether a user is depressed or not using features extracted from his/her activities in the network and tweets. The results showed that the more features are used, the higher are the accuracy and F-measure scores in detecting depressed users. This method is a data-driven, predictive approach for early detection of depression or other mental illnesses. This study's main contribution is the exploration part of the features and its impact on detecting the depression level.

  • An Attention-Based GRU Network for Anomaly Detection from System Logs

    Yixi XIE  Lixin JI  Xiaotao CHENG  

     
    LETTER-Information Network

      Pubricized:
    2020/05/01
      Vol:
    E103-D No:8
      Page(s):
    1916-1919

    System logs record system states and significant events at various critical points to help debug performance issues and failures. Therefore, the rapid and accurate detection of the system log is crucial to the security and stability of the system. In this paper, proposed is a novel attention-based neural network model, which would learn log patterns from normal execution. Concretely, our model adopts a GRU module with attention mechanism to extract the comprehensive and intricate correlations and patterns embedded in a sequence of log entries. Experimental results demonstrate that our proposed approach is effective and achieve better performance than conventional methods.

  • Development of a Low Frequency Electric Field Probe Integrating Data Acquisition and Storage

    Zhongyuan ZHOU  Mingjie SHENG  Peng LI  Peng HU  Qi ZHOU  

     
    PAPER-Electromagnetic Theory

      Pubricized:
    2020/02/27
      Vol:
    E103-C No:8
      Page(s):
    345-352

    A low frequency electric field probe that integrates data acquisition and storage is developed in this paper. An electric small monopole antenna printed on the circuit board is used as the receiving antenna; the rear end of the monopole antenna is connected to the integral circuit to achieve the flat frequency response; the logarithmic detection method is applied to obtain a high measurement dynamic range. In addition, a Microprogrammed Control Unit is set inside to realize data acquisition and storage. The size of the probe developed is not exceeding 20 mm × 20 mm × 30 mm. The field strength 0.2 V/m ~ 261 V/m can be measured in the frequency range of 500 Hz ~ 10 MHz, achieving a dynamic range over 62 dB. It is suitable for low frequency electric field strength measurement and shielding effectiveness test of small shield.

  • H-TLA: Hybrid-Based and Two-Level Addressing Architecture for IoT Devices and Services

    Sangwon SEO  Sangbae YUN  Jaehong KIM  Inkyo KIM  Seongwook JIN  Seungryoul MAENG  

     
    LETTER-Computer System

      Pubricized:
    2020/05/14
      Vol:
    E103-D No:8
      Page(s):
    1911-1915

    An increasing number of IoT devices are being introduced to the market in many industries, and the number of devices is expected to exceed billions in the near future. With this trend, many researchers have proposed new architectures to manage IoT devices, but the proposed architecture requires a huge memory footprint and computation overheads to look-up billions of devices. This paper proposes a hybrid hashing architecture called H- TLA to solve the problem from an architectural point of view, instead of modifying a hashing algorithm or designing a new one. We implemented a prototype system that shows about a 30% increase in performance while conserving uniformity. Therefore, we show an efficient architecture-level approach for addressing billions of devices.

  • Improving Faster R-CNN Framework for Multiscale Chinese Character Detection and Localization

    Minseong KIM  Hyun-Chul CHOI  

     
    LETTER-Pattern Recognition

      Pubricized:
    2020/04/06
      Vol:
    E103-D No:7
      Page(s):
    1777-1781

    Faster R-CNN uses a region proposal network which consists of a single scale convolution filter and fully connected networks to localize detected regions. However, using a single scale filter is not enough to detect full regions of characters. In this letter, we propose a simple but effective way, i.e., utilizing variously sized convolution filters, to accurately detect Chinese characters of multiple scales in documents. We experimentally verified that our method improved IoU by 4% and detection rate by 3% than the previous single scale Faster R-CNN method.

  • Intrusion Detection System Using Deep Learning and Its Application to Wi-Fi Network

    Kwangjo KIM  

     
    INVITED PAPER

      Pubricized:
    2020/03/31
      Vol:
    E103-D No:7
      Page(s):
    1433-1447

    Deep learning is gaining more and more lots of attractions and better performance in implementing the Intrusion Detection System (IDS), especially for feature learning. This paper presents the state-of-the-art advances and challenges in IDS using deep learning models, which have been achieved the big performance enhancements in the field of computer vision, natural language processing, and image/audio processing than the traditional methods. After providing a systematic and methodical description of the latest developments in deep learning from the points of the deployed architectures and techniques, we suggest the pros-and-cons of all the deep learning-based IDS, and discuss the importance of deep learning models as feature learning approach. For this, the author has suggested the concept of the Deep-Feature Extraction and Selection (D-FES). By combining the stacked feature extraction and the weighted feature selection for D-FES, our experiment was verified to get the best performance of detection rate, 99.918% and false alarm rate, 0.012% to detect the impersonation attacks in Wi-Fi network which can be achieved better than the previous publications. Summary and further challenges are suggested as a concluding remark.

  • S-Parameter Analysis for Balanced and Unbalanced Modes Corresponding Dissipated Power of a Small Antenna

    Takashi YANAGI  Yasuhiro NISHIOKA  Toru FUKASAWA  Naofumi YONEDA  Hiroaki MIYASHITA  

     
    PAPER-Antennas and Propagation

      Pubricized:
    2020/01/15
      Vol:
    E103-B No:7
      Page(s):
    780-786

    In this paper, an analysis method for calculating balanced and unbalanced modes of a small antenna is summarized. Modal condactances which relate dissipated power of the antenna are directly obtained from standard S-parameters that we can measure by a 2-port network analyzer. We demonstrate the validity and effectiveness of the proposed method by simulation and measurement for a dipole antenna with unbalaned feed. The ratio of unbalanced-mode power to the total power (unbalanced-mode power ratio) calculated by the proposed method agrees precisely with that yielded by the conventional method using measured radiation patterns. Furthermore, we analyze a small loop antenna with unbalanced feed by the proposed method and show that the self-balancing characteristic appears when the loop is set in resonant state by loading capacitances or the whole length of the loop is less than 1/20th the wavelength.

  • DomainScouter: Analyzing the Risks of Deceptive Internationalized Domain Names

    Daiki CHIBA  Ayako AKIYAMA HASEGAWA  Takashi KOIDE  Yuta SAWABE  Shigeki GOTO  Mitsuaki AKIYAMA  

     
    PAPER-Network and System Security

      Pubricized:
    2020/03/19
      Vol:
    E103-D No:7
      Page(s):
    1493-1511

    Internationalized domain names (IDNs) are abused to create domain names that are visually similar to those of legitimate/popular brands. In this work, we systematize such domain names, which we call deceptive IDNs, and analyze the risks associated with them. In particular, we propose a new system called DomainScouter to detect various deceptive IDNs and calculate a deceptive IDN score, a new metric indicating the number of users that are likely to be misled by a deceptive IDN. We perform a comprehensive measurement study on the identified deceptive IDNs using over 4.4 million registered IDNs under 570 top-level domains (TLDs). The measurement results demonstrate that there are many previously unexplored deceptive IDNs targeting non-English brands or combining other domain squatting methods. Furthermore, we conduct online surveys to examine and highlight vulnerabilities in user perceptions when encountering such IDNs. Finally, we discuss the practical countermeasures that stakeholders can take against deceptive IDNs.

1601-1620hit(21534hit)