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1381-1400hit(16314hit)

  • Combining Parallel Adaptive Filtering and Wavelet Threshold Denoising for Photoplethysmography-Based Pulse Rate Monitoring during Intensive Physical Exercise

    Chunting WAN  Dongyi CHEN  Juan YANG  Miao HUANG  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2019/12/03
      Vol:
    E103-D No:3
      Page(s):
    612-620

    Real-time pulse rate (PR) monitoring based on photoplethysmography (PPG) has been drawn much attention in recent years. However, PPG signal detected under movement is easily affected by random noises, especially motion artifacts (MA), affecting the accuracy of PR estimation. In this paper, a parallel method structure is proposed, which effectively combines wavelet threshold denoising with recursive least squares (RLS) adaptive filtering to remove interference signals, and uses spectral peak tracking algorithm to estimate real-time PR. Furthermore, we propose a parallel structure RLS adaptive filtering to increase the amplitude of spectral peak associated with PR for PR estimation. This method is evaluated by using the PPG datasets of the 2015 IEEE Signal Processing Cup. Experimental results on the 12 training datasets during subjects' walking or running show that the average absolute error (AAE) is 1.08 beats per minute (BPM) and standard deviation (SD) is 1.45 BPM. In addition, the AAE of PR on the 10 testing datasets during subjects' fast running accompanied with wrist movements can reach 2.90 BPM. Furthermore, the results indicate that the proposed approach keeps high estimation accuracy of PPG signal even with strong MA.

  • Joint Angle, Velocity, and Range Estimation Using 2D MUSIC and Successive Interference Cancellation in FMCW MIMO Radar System

    Jonghyeok LEE  Sunghyun HWANG  Sungjin YOU  Woo-Jin BYUN  Jaehyun PARK  

     
    PAPER-Sensing

      Pubricized:
    2019/09/11
      Vol:
    E103-B No:3
      Page(s):
    283-290

    To estimate angle, velocity, and range information of multiple targets jointly in FMCW MIMO radar, two-dimensional (2D) MUSIC with matched filtering and FFT algorithm is proposed. By reformulating the received FMCW signal of the colocated MIMO radar, we exploit 2D MUSIC to estimate the angle and Doppler frequency of multiple targets. Then by using a matched filter together with the estimated angle and Doppler frequency and FFT operation, the range of the target is estimated. To effectively estimate the parameters of multiple targets with large distance differences, we also propose a successive interference cancellation method that uses the orthogonal projection. That is, rather than estimating the multiple target parameters simultaneously using 2D MUSIC, we estimate the target parameters sequentially, in which the parameters of the target having strongest reflected power are estimated first and then, their effect on the received signal is canceled out by using the orthogonal projection. Simulations verify the performance of the proposed algorithm.

  • Simulated Annealing Method for Relaxed Optimal Rule Ordering

    Takashi HARADA  Ken TANAKA  Kenji MIKAWA  

     
    PAPER

      Pubricized:
    2019/12/20
      Vol:
    E103-D No:3
      Page(s):
    509-515

    Recent years have witnessed a rapid increase in cyber-attacks through unauthorized accesses and DDoS attacks. Since packet classification is a fundamental technique to prevent such illegal communications, it has gained considerable attention. Packet classification is achieved with a linear search on a classification rule list that represents the packet classification policy. As such, a large number of rules can result in serious communication latency. To decrease this latency, the problem is formalized as optimal rule ordering (ORO). In most cases, this problem aims to find the order of rules that minimizes latency while satisfying the dependency relation of the rules, where rules ri and rj are dependent if there is a packet that matches both ri and rj and their actions applied to packets are different. However, there is a case in which although the ordering violates the dependency relation, the ordering satisfies the packet classification policy. Since such an ordering can decrease the latency compared to an ordering under the constraint of the dependency relation, we have introduced a new model, called relaxed optimal rule ordering (RORO). In general, it is difficult to determine whether an ordering satisfies the classification policy, even when it violates the dependency relation, because this problem contains unsatisfiability. However, using a zero-suppressed binary decision diagram (ZDD), we can determine it in a reasonable amount of time. In this paper, we present a simulated annealing method for RORO which interchanges rules by determining whether rules ri and rj can be interchanged in terms of policy violation using the ZDD. The experimental results show that our method decreases latency more than other heuristics.

  • Generative Moment Matching Network-Based Neural Double-Tracking for Synthesized and Natural Singing Voices

    Hiroki TAMARU  Yuki SAITO  Shinnosuke TAKAMICHI  Tomoki KORIYAMA  Hiroshi SARUWATARI  

     
    PAPER-Speech and Hearing

      Pubricized:
    2019/12/23
      Vol:
    E103-D No:3
      Page(s):
    639-647

    This paper proposes a generative moment matching network (GMMN)-based post-filtering method for providing inter-utterance pitch variation to singing voices and discusses its application to our developed mixing method called neural double-tracking (NDT). When a human singer sings and records the same song twice, there is a difference between the two recordings. The difference, which is called inter-utterance variation, enriches the performer's musical expression and the audience's experience. For example, it makes every concert special because it never recurs in exactly the same manner. Inter-utterance variation enables a mixing method called double-tracking (DT). With DT, the same phrase is recorded twice, then the two recordings are mixed to give richness to singing voices. However, in synthesized singing voices, which are commonly used to create music, there is no inter-utterance variation because the synthesis process is deterministic. There is also no inter-utterance variation when only one voice is recorded. Although there is a signal processing-based method called artificial DT (ADT) to layer singing voices, the signal processing results in unnatural sound artifacts. To solve these problems, we propose a post-filtering method for randomly modulating synthesized or natural singing voices as if the singer sang again. The post-filter built with our method models the inter-utterance pitch variation of human singing voices using a conditional GMMN. Evaluation results indicate that 1) the proposed method provides perceptible and natural inter-utterance variation to synthesized singing voices and that 2) our NDT exhibits higher double-trackedness than ADT when applied to both synthesized and natural singing voices.

  • Software-Based Time-Aware Shaper for Time-Sensitive Networks Open Access

    Yasin OGE  Yuta KOBAYASHI  Takahiro YAMAURA  Tomonori MAEGAWA  

     
    PAPER-Network

      Pubricized:
    2019/09/09
      Vol:
    E103-B No:3
      Page(s):
    167-180

    This paper presents the design, implementation, and evaluation of a time-aware shaper, which is a traffic shaper specifically designed for IEEE 802.1Qbv-compliant time-sensitive networks. The proposed design adopts a software-based approach rather than using a dedicated custom logic chip such as an ASIC or FPGA. In particular, the proposed approach includes a run-time scheduler and a network interface card (NIC) that supports a time-based transmission scheme (i.e., launch-time feature). The run-time scheduler prefetches information (i.e., gate control entry) ahead of time from a given gate control list. With the prefetched information, the scheduler determines a launch time for each frame, and the NIC controls the time at which the transmission of each frame is started in a highly punctual manner. Evaluation results show that the proposed shaper triggers transmission of multiple time-sensitive streams at their intended timings in accordance with a given gate control list, even in the presence of high-bandwidth background traffic. Furthermore, we compare the timing accuracy of frame transmission with and without use of the launch-time feature of the NIC. Results indicate that the proposed shaper significantly reduces jitter of time-sensitive streams (to less than 0.1 µs) unlike a baseline implementation that does not use the launch-time feature.

  • Local Memory Mapping of Multicore Processors on an Automatic Parallelizing Compiler

    Yoshitake OKI  Yuto ABE  Kazuki YAMAMOTO  Kohei YAMAMOTO  Tomoya SHIRAKAWA  Akimasa YOSHIDA  Keiji KIMURA  Hironori KASAHARA  

     
    PAPER

      Vol:
    E103-C No:3
      Page(s):
    98-109

    Utilization of local memory from real-time embedded systems to high performance systems with multi-core processors has become an important factor for satisfying hard deadline constraints. However, challenges lie in the area of efficiently managing the memory hierarchy, such as decomposing large data into small blocks to fit onto local memory and transferring blocks for reuse and replacement. To address this issue, this paper presents a compiler optimization method that automatically manage local memory of multi-core processors. The method selects and maps multi-dimensional data onto software specified memory blocks called Adjustable Blocks. These blocks are hierarchically divisible with varying sizes defined by the features of the input application. Moreover, the method introduces mapping structures called Template Arrays to maintain the indices of the decomposed multi-dimensional data. The proposed work is implemented on the OSCAR automatic parallelizing compiler and evaluations were performed on the Renesas RP2 8-core processor. Experimental results from NAS Parallel Benchmark, SPEC benchmark, and multimedia applications show the effectiveness of the method, obtaining maximum speed-ups of 20.44 with 8 cores utilizing local memory from single core sequential versions that use off-chip memory.

  • BER due to Intersymbol Interference in Maximal-Ratio Combining Reception Analyzed Based on Equivalent Transmission-Path Model

    Yoshio KARASAWA  

     
    PAPER-Antennas and Propagation

      Pubricized:
    2019/09/06
      Vol:
    E103-B No:3
      Page(s):
    229-239

    The equivalent transmission-path model is a propagation-oriented channel model for predicting the bit error rate due to intersymbol interference in single-input single-output systems. We extend this model to develop a new calculation scheme for maximal-ratio combining diversity reception in single-input multiple-output configurations. A key part of the study is to derive a general formula expressing the joint probability density function of the amplitude ratio and phase difference of the two-path model. In this derivation, we mainly take a theoretical approach with the aid of Monte Carlo simulation. Then, very high-accuracy estimation of the average bit error rate due to intersymbol interference (ISI) for CQPSK calculated based on the model is confirmed by computer simulation. Finally, we propose a very simple calculation formula for the prediction of the BER due to ISI that is commonly applicable to various modulation/demodulation schemes, such as CQPSK, DQPSK, 16QAM, and CBPSK in maximal-ratio combining diversity reception.

  • Superpixel Segmentation Based on Global Similarity and Contour Region Transform

    Bing LUO  Junkai XIONG  Li XU  Zheng PEI  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2019/12/03
      Vol:
    E103-D No:3
      Page(s):
    716-719

    This letter proposes a new superpixel segmentation algorithm based on global similarity and contour region transformation. The basic idea is that pixels surrounded by the same contour are more likely to belong to the same object region, which could be easily clustered into the same superpixel. To this end, we use contour scanning to estimate the global similarity between pixels and corresponded centers. In addition, we introduce pixel's gradient information of contour transform map to enhance the pixel's global similarity to overcome the missing contours in blurred region. Benefited from our global similarity, the proposed method could adherent with blurred and low contrast boundaries. A large number of experiments on BSDS500 and VOC2012 datasets show that the proposed algorithm performs better than traditional SLIC.

  • Combining CNN and Broad Learning for Music Classification

    Huan TANG  Ning CHEN  

     
    PAPER-Music Information Processing

      Pubricized:
    2019/12/05
      Vol:
    E103-D No:3
      Page(s):
    695-701

    Music classification has been inspired by the remarkable success of deep learning. To enhance efficiency and ensure high performance at the same time, a hybrid architecture that combines deep learning and Broad Learning (BL) is proposed for music classification tasks. At the feature extraction stage, the Random CNN (RCNN) is adopted to analyze the Mel-spectrogram of the input music sound. Compared with conventional CNN, RCNN has more flexible structure to adapt to the variance contained in different types of music. At the prediction stage, the BL technique is introduced to enhance the prediction accuracy and reduce the training time as well. Experimental results on three benchmark datasets (GTZAN, Ballroom, and Emotion) demonstrate that: i) The proposed scheme achieves higher classification accuracy than the deep learning based one, which combines CNN and LSTM, on all three benchmark datasets. ii) Both RCNN and BL contribute to the performance improvement of the proposed scheme. iii) The introduction of BL also helps to enhance the prediction efficiency of the proposed scheme.

  • On Performance of Deep Learning for Harmonic Spur Cancellation in OFDM Systems

    Ziming HE  

     
    LETTER-Mobile Information Network and Personal Communications

      Vol:
    E103-A No:2
      Page(s):
    576-579

    In this letter, the performance of a state-of-the-art deep learning (DL) algorithm in [5] is analyzed and evaluated for orthogonal frequency-division multiplexing (OFDM) receivers, in the presence of harmonic spur interference. Moreover, a novel spur cancellation receiver structure and algorithm are proposed to enhance the traditional OFDM receivers, and serve as a performance benchmark for the DL algorithm. It is found that the DL algorithm outperforms the traditional algorithm and is much more robust to spur carrier frequency offset.

  • Template-Based Monte-Carlo Test-Suite Generation for Large and Complex Simulink Models Open Access

    Takashi TOMITA  Daisuke ISHII  Toru MURAKAMI  Shigeki TAKEUCHI  Toshiaki AOKI  

     
    PAPER

      Vol:
    E103-A No:2
      Page(s):
    451-461

    MATLAB/Simulink is the de facto standard tool for the model-based development (MBD) of control software for automotive systems. A Simulink model developed in MBD for real automotive systems involves complex computation as well as tens of thousands of blocks. In this paper, we focus on decision coverage (DC), condition coverage (CC) and modified condition/decision coverage (MC/DC) criteria, and propose a Monte-Carlo test suite generation method for large and complex Simulink models. In the method, a candidate test case is generated by assigning random values to the parameters of signal templates with specific waveforms. We try to find contributable candidates in a plausible and understandable search space, specified by a set of templates. We implemented the method as a tool, and our experimental evaluation showed that the tool was able to generate test suites for industrial implementation models with higher coverages and shorter execution times than Simulink Design Verifier. Additionally, the tool includes a fast coverage measurement engine, which demonstrated better performance than Simulink Coverage in our experiments.

  • Joint Energy-Efficiency and Throughput Optimization with Admission Control and Resource Allocation in Cognitive Radio Networks

    Jain-Shing LIU  Chun-Hung LIN  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Pubricized:
    2019/07/26
      Vol:
    E103-B No:2
      Page(s):
    139-147

    In this work, we address a joint energy efficiency (EE) and throughput optimization problem in interweave cognitive radio networks (CRNs) subject to scheduling, power, and stability constraints, which could be solved through traffic admission control, channel allocation, and power allocation. Specifically, the joint objective is to concurrently optimize the system EE and the throughput of secondary user (SU), while satisfying the minimum throughput requirement of primary user (PU), the throughput constraint of SU, and the scheduling and power control constraints that must be considered. To achieve these goals, our algorithm independently and simultaneously makes control decisions on admission and transmission to maximize a joint utility of EE and throughput under time-varying conditions of channel and traffic without a priori knowledge. Specially, the proposed scheduling algorithm has polynomial time efficiency, and the power control algorithms as well as the admission control algorithm involved are simply threshold-based and thus very computationally efficient. Finally, numerical analyses show that our proposals achieve both system stability and optimal utility.

  • An Energy-Efficient Task Scheduling for Near Real-Time Systems on Heterogeneous Multicore Processors

    Takashi NAKADA  Hiroyuki YANAGIHASHI  Kunimaro IMAI  Hiroshi UEKI  Takashi TSUCHIYA  Masanori HAYASHIKOSHI  Hiroshi NAKAMURA  

     
    PAPER-Software System

      Pubricized:
    2019/11/01
      Vol:
    E103-D No:2
      Page(s):
    329-338

    Near real-time periodic tasks, which are popular in multimedia streaming applications, have deadline periods that are longer than the input intervals thanks to buffering. For such applications, the conventional frame-based schedulings cannot realize the optimal scheduling due to their shortsighted deadline assumptions. To realize globally energy-efficient executions of these applications, we propose a novel task scheduling algorithm, which takes advantage of the long deadline period. We confirm our approach can take advantage of the longer deadline period and reduce the average power consumption by up to 18%.

  • Sign Reversal Channel Switching Method in Space-Time Block Code for OFDM Systems

    Hyeok Koo JUNG  

     
    LETTER-Communication Theory and Signals

      Vol:
    E103-A No:2
      Page(s):
    567-570

    This paper proposes a simple source data exchange method for channel switching in space-time block code. If one transmits source data on another antenna, then the receiver should change combining method in order to adapt it. No one except knowing the channel switching sequence can decode the received data correctly. In case of exchanging data for channel switching, four orthogonal frequency division multiplexing symbols are exchanged according to a format of space-time block code. In this paper, I proposes two simple sign exchanges without exchanging four orthogonal-frequency division multiplexing symbols which occurs a different combining and channel switching method in the receiver.

  • Software Process Capability Self-Assessment Support System Based on Task and Work Product Characteristics: A Case Study of ISO/IEC 29110 Standard

    Apinporn METHAWACHANANONT  Marut BURANARACH  Pakaimart AMSURIYA  Sompol CHAIMONGKHON  Kamthorn KRAIRAKSA  Thepchai SUPNITHI  

     
    PAPER-Software Engineering

      Pubricized:
    2019/10/17
      Vol:
    E103-D No:2
      Page(s):
    339-347

    A key driver of software business growth in developing countries is the survival of software small and medium-sized enterprises (SMEs). Quality of products is a critical factor that can indicate the future of the business by building customer confidence. Software development agencies need to be aware of meeting international standards in software development process. In practice, consultants and assessors are usually employed as the primary solution, which can impact the budget in case of small businesses. Self-assessment tools for software development process can potentially reduce time and cost of formal assessment for software SMEs. However, the existing support methods and tools are largely insufficient in terms of process coverage and semi-automated evaluation. This paper proposes to apply a knowledge-based approach in development of a self-assessment and gap analysis support system for the ISO/IEC 29110 standard. The approach has an advantage that insights from domain experts and the standard are captured in the knowledge base in form of decision tables that can be flexibly managed. Our knowledge base is unique in that task lists and work products defined in the standard are broken down into task and work product characteristics, respectively. Their relation provides the links between Task List and Work Product which make users more understand and influence self-assessment. A prototype support system was developed to assess the level of software development capability of the agencies based on the ISO/IEC 29110 standard. A preliminary evaluation study showed that the system can improve performance of users who are inexperienced in applying ISO/IEC 29110 standard in terms of task coverage and user's time and effort compared to the traditional self-assessment method.

  • CLAP: Classification of Android PUAs by Similarity of DNS Queries

    Mitsuhiro HATADA  Tatsuya MORI  

     
    PAPER-Network Security

      Pubricized:
    2019/11/11
      Vol:
    E103-D No:2
      Page(s):
    265-275

    This work develops a system called CLAP that detects and classifies “potentially unwanted applications” (PUAs) such as adware or remote monitoring tools. Our approach leverages DNS queries made by apps. Using a large sample of Android apps from third-party marketplaces, we first reveal that DNS queries can provide useful information for detection and classification of PUAs. We then show that existing DNS blacklists are limited when performing these tasks. Finally, we demonstrate that the CLAP system performs with high accuracy.

  • A Family of New 16-QAM Golay Complementary Sequences without Higher PEP Upper Bounds

    Fanxin ZENG  Xiping HE  Guixin XUAN  Zhenyu ZHANG  Yanni PENG  Li YAN  

     
    LETTER-Information Theory

      Vol:
    E103-A No:2
      Page(s):
    547-552

    In an OFDM communication system using quadrature amplitude modulation (QAM) signals, peak envelope powers (PEPs) of the transmitted signals can be well controlled by using QAM Golay complementary sequence pairs (CSPs). In this letter, by making use of a new construction, a family of new 16-QAM Golay CSPs of length N=2m (integer m≥2) with binary inputs is presented, and all the resultant pairs have the PEP upper bound 2N. However, in the existing such pairs from other references their PEP upper bounds can arrive at 3.6N when the worst case happens. In this sense, novel pairs are good candidates for OFDM applications.

  • Rust Detection of Steel Structure via One-Class Classification and L2 Sparse Representation with Decision Fusion

    Guizhong ZHANG  Baoxian WANG  Zhaobo YAN  Yiqiang LI  Huaizhi YANG  

     
    LETTER-Artificial Intelligence, Data Mining

      Pubricized:
    2019/11/11
      Vol:
    E103-D No:2
      Page(s):
    450-453

    In this work, we present one novel rust detection method based upon one-class classification and L2 sparse representation (SR) with decision fusion. Firstly, a new color contrast descriptor is proposed for extracting the rust features of steel structure images. Considering that the patterns of rust features are more simplified than those of non-rust ones, one-class support vector machine (SVM) classifier and L2 SR classifier are designed with these rust image features, respectively. After that, a multiplicative fusion rule is advocated for combining the one-class SVM and L2 SR modules, thereby achieving more accurate rust detecting results. In the experiments, we conduct numerous experiments, and when compared with other developed rust detectors, the presented method can offer better rust detecting performances.

  • Architecture and Design of Coarse/Fine Hybrid Granular Routing Optical Networks Open Access

    Yusaku ITO  Yojiro MORI  Hiroshi HASEGAWA  Ken-ichi SATO  

     
    PAPER-Fiber-Optic Transmission for Communications

      Pubricized:
    2019/07/26
      Vol:
    E103-B No:2
      Page(s):
    118-129

    A novel coarse and fine hybrid granular routing network architecture is proposed. Virtual direct links (VDLs) defined by the coarse granular routing to bridge distant node pairs, and routing via VDL mitigate the spectrum narrowing caused by optical filtering at wavelength-selective switches in ROADM (Reconfigurable Optical Add/Drop Multiplexing) nodes. The impairment mitigation yields denser channel accommodation in the frequency domain, which substantially increases fiber spectral efficiency. The proposed network simultaneously utilizes fine granular optical path level routing so that optical paths can be effectively accommodated in VDLs. The newly developed network design algorithm presented in this paper effectively implements routing and spectrum assignment to paths in addition to optimizing VDL establishment and path accommodation to VDLs. The effectiveness of the proposed architecture is demonstrated through both numerical and experimental evaluations; the number of fibers necessary in a network, and the spectrum bandwidth and hop count product are, respectively, reduced by up to 18% and increased by up to 111%.

  • Recurrent Neural Network Compression Based on Low-Rank Tensor Representation

    Andros TJANDRA  Sakriani SAKTI  Satoshi NAKAMURA  

     
    PAPER-Music Information Processing

      Pubricized:
    2019/10/17
      Vol:
    E103-D No:2
      Page(s):
    435-449

    Recurrent Neural Network (RNN) has achieved many state-of-the-art performances on various complex tasks related to the temporal and sequential data. But most of these RNNs require much computational power and a huge number of parameters for both training and inference stage. Several tensor decomposition methods are included such as CANDECOMP/PARAFAC (CP), Tucker decomposition and Tensor Train (TT) to re-parameterize the Gated Recurrent Unit (GRU) RNN. First, we evaluate all tensor-based RNNs performance on sequence modeling tasks with a various number of parameters. Based on our experiment results, TT-GRU achieved the best results in a various number of parameters compared to other decomposition methods. Later, we evaluate our proposed TT-GRU with speech recognition task. We compressed the bidirectional GRU layers inside DeepSpeech2 architecture. Based on our experiment result, our proposed TT-format GRU are able to preserve the performance while reducing the number of GRU parameters significantly compared to the uncompressed GRU.

1381-1400hit(16314hit)