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941-960hit(16314hit)

  • Patent One-Stop Service Business Model Based on Scientific and Technological Resource Bundle

    Fanying ZHENG  Yangjian JI  Fu GU  Xinjian GU  Jin ZHANG  

     
    PAPER

      Pubricized:
    2021/04/26
      Vol:
    E104-D No:8
      Page(s):
    1281-1291

    To address slow response and scattered resources in patent service, this paper proposes a one-stop service business model based on scientific and technological resource bundle. The proposed one-step model is composed of a project model, a resource bundle model and a service product model through Web Service integration. This paper describes the patent resource bundle model from the aspects of content and context, and designs the configuration of patent service products and patent resource bundle. The model is then applied to the patent service of the Yangtze River Delta urban agglomeration in China, and the monthly agent volume increased by 38.8%, and the average response time decreased by 14.3%. Besides, it is conducive to improve user satisfaction and resource sharing efficiency of urban agglomeration.

  • Improvement of CT Reconstruction Using Scattered X-Rays

    Shota ITO  Naohiro TODA  

     
    PAPER-Biological Engineering

      Pubricized:
    2021/05/06
      Vol:
    E104-D No:8
      Page(s):
    1378-1385

    A neural network that outputs reconstructed images based on projection data containing scattered X-rays is presented, and the proposed scheme exhibits better accuracy than conventional computed tomography (CT), in which the scatter information is removed. In medical X-ray CT, it is a common practice to remove scattered X-rays using a collimator placed in front of the detector. In this study, the scattered X-rays were assumed to have useful information, and a method was devised to utilize this information effectively using a neural network. Therefore, we generated 70,000 projection data by Monte Carlo simulations using a cube comprising 216 (6 × 6 × 6) smaller cubes having random density parameters as the target object. For each projection simulation, the densities of the smaller cubes were reset to different values, and detectors were deployed around the target object to capture the scattered X-rays from all directions. Then, a neural network was trained using these projection data to output the densities of the smaller cubes. We confirmed through numerical evaluations that the neural-network approach that utilized scattered X-rays reconstructed images with higher accuracy than did the conventional method, in which the scattered X-rays were removed. The results of this study suggest that utilizing the scattered X-ray information can help significantly reduce patient dosing during imaging.

  • DCUIP Poisoning Attack in Intel x86 Processors

    Youngjoo SHIN  

     
    LETTER-Dependable Computing

      Pubricized:
    2021/05/13
      Vol:
    E104-D No:8
      Page(s):
    1386-1390

    Cache prefetching technique brings huge benefits to performance improvement, but it comes at the cost of microarchitectural security in processors. In this letter, we deep dive into internal workings of a DCUIP prefetcher, which is one of prefetchers equipped in Intel processors. We discover that a DCUIP table is shared among different execution contexts in hyperthreading-enabled processors, which leads to another microarchitectural vulnerability. By exploiting the vulnerability, we propose a DCUIP poisoning attack. We demonstrate an AES encryption key can be extracted from an AES-NI implementation by mounting the proposed attack.

  • A Two-Stage Attention Based Modality Fusion Framework for Multi-Modal Speech Emotion Recognition

    Dongni HU  Chengxin CHEN  Pengyuan ZHANG  Junfeng LI  Yonghong YAN  Qingwei ZHAO  

     
    LETTER-Human-computer Interaction

      Pubricized:
    2021/04/30
      Vol:
    E104-D No:8
      Page(s):
    1391-1394

    Recently, automated recognition and analysis of human emotion has attracted increasing attention from multidisciplinary communities. However, it is challenging to utilize the emotional information simultaneously from multiple modalities. Previous studies have explored different fusion methods, but they mainly focused on either inter-modality interaction or intra-modality interaction. In this letter, we propose a novel two-stage fusion strategy named modality attention flow (MAF) to model the intra- and inter-modality interactions simultaneously in a unified end-to-end framework. Experimental results show that the proposed approach outperforms the widely used late fusion methods, and achieves even better performance when the number of stacked MAF blocks increases.

  • Unified Likelihood Ratio Estimation for High- to Zero-Frequency N-Grams

    Masato KIKUCHI  Kento KAWAKAMI  Kazuho WATANABE  Mitsuo YOSHIDA  Kyoji UMEMURA  

     
    PAPER-Mathematical Systems Science

      Pubricized:
    2021/02/08
      Vol:
    E104-A No:8
      Page(s):
    1059-1074

    Likelihood ratios (LRs), which are commonly used for probabilistic data processing, are often estimated based on the frequency counts of individual elements obtained from samples. In natural language processing, an element can be a continuous sequence of N items, called an N-gram, in which each item is a word, letter, etc. In this paper, we attempt to estimate LRs based on N-gram frequency information. A naive estimation approach that uses only N-gram frequencies is sensitive to low-frequency (rare) N-grams and not applicable to zero-frequency (unobserved) N-grams; these are known as the low- and zero-frequency problems, respectively. To address these problems, we propose a method for decomposing N-grams into item units and then applying their frequencies along with the original N-gram frequencies. Our method can obtain the estimates of unobserved N-grams by using the unit frequencies. Although using only unit frequencies ignores dependencies between items, our method takes advantage of the fact that certain items often co-occur in practice and therefore maintains their dependencies by using the relevant N-gram frequencies. We also introduce a regularization to achieve robust estimation for rare N-grams. Our experimental results demonstrate that our method is effective at solving both problems and can effectively control dependencies.

  • An Algebraic Approach to Verifying Galois-Field Arithmetic Circuits with Multiple-Valued Characteristics

    Akira ITO  Rei UENO  Naofumi HOMMA  

     
    PAPER-Logic Design

      Pubricized:
    2021/04/28
      Vol:
    E104-D No:8
      Page(s):
    1083-1091

    This study presents a formal verification method for Galois-field (GF) arithmetic circuits with the characteristics of more than two values. The proposed method formally verifies the correctness of circuit functionality (i.e., the input-output relations given as GF-polynomials) by checking the equivalence between a specification and a gate-level netlist. We represent a netlist using simultaneous algebraic equations and solve them based on a novel polynomial reduction method that can be efficiently applied to arithmetic over extension fields $mathbb{F}_{p^m}$, where the characteristic p is larger than two. By using the reverse topological term order to derive the Gröbner basis, our method can complete the verification, even when a target circuit includes bugs. In addition, we introduce an extension of the Galois-Field binary moment diagrams to perform the polynomial reductions faster. Our experimental results show that the proposed method can efficiently verify practical $mathbb{F}_{p^m}$ arithmetic circuits, including those used in modern cryptography. Moreover, we demonstrate that the extended polynomial reduction technique can enable verification that is up to approximately five times faster than the original one.

  • Minimax Design of Sparse IIR Filters Using Sparse Linear Programming Open Access

    Masayoshi NAKAMOTO  Naoyuki AIKAWA  

     
    PAPER-Digital Signal Processing

      Pubricized:
    2021/02/15
      Vol:
    E104-A No:8
      Page(s):
    1006-1018

    Recent trends in designing filters involve development of sparse filters with coefficients that not only have real but also zero values. These sparse filters can achieve a high performance through optimizing the selection of the zero coefficients and computing the real (non-zero) coefficients. Designing an infinite impulse response (IIR) sparse filter is more challenging than designing a finite impulse response (FIR) sparse filter. Therefore, studies on the design of IIR sparse filters have been rare. In this study, we consider IIR filters whose coefficients involve zero value, called sparse IIR filter. First, we formulate the design problem as a linear programing problem without imposing any stability condition. Subsequently, we reformulate the design problem by altering the error function and prepare several possible denominator polynomials with stable poles. Finally, by incorporating these methods into successive thinning algorithms, we develop a new design algorithm for the filters. To demonstrate the effectiveness of the proposed method, its performance is compared with that of other existing methods.

  • Generation of Large-Amplitude Pulses through the Pulse Shortening Superposed in Series-Connected Tunnel-Diode Transmission Line

    Koichi NARAHARA  

     
    BRIEF PAPER-Electronic Circuits

      Pubricized:
    2021/02/08
      Vol:
    E104-C No:8
      Page(s):
    394-397

    A scheme is proposed for generation of large-amplitude short pulses using a transmission line with regularly spaced series-connected tunnel diodes (TDs). In the case where the loaded TD is unique, it is established that the leading edge of the inputted pulse moves slower than the trailing edge, when the pulse amplitude exceeds the peak voltage of the loaded TD; therefore, the pulse width is autonomously reduced through propagation in the line. In this study, we find that this property is true even when the several series-connected TDs are loaded periodically. By these mechanisms, the TD line succeeds in generating large and short pulses. Herein, we clarify the design criteria of the TD line, together with both numerical and experimental validation.

  • Transmission Loss of Optical Fibers; Achievements in Half a Century Open Access

    Hiroo KANAMORI  

     
    INVITED PAPER-Optical Fiber for Communications

      Pubricized:
    2021/02/15
      Vol:
    E104-B No:8
      Page(s):
    922-933

    This paper reviews the evolutionary process that reduced the transmission loss of silica optical fibers from the report of 20dB/km by Corning in 1970 to the current record-low loss. At an early stage, the main effort was to remove impurities especially hydroxy groups for fibers with GeO2-SiO2 core, resulting in the loss of 0.20dB/km in 1980. In order to suppress Rayleigh scattering due to composition fluctuation, pure-silica-core fibers were developed, and the loss of 0.154dB/km was achieved in 1986. As the residual main factor of the loss, Rayleigh scattering due to density fluctuation was actively investigated by utilizing IR and Raman spectroscopy in the 1990s and early 2000s. Now, ultra-low-loss fibers with the loss of 0.150dB/km are commercially available in trans-oceanic submarine cable systems.

  • Extended-Domain Golomb Code and Symmetry of Relative Redundancy

    Ryosuke SUGIURA  Yutaka KAMAMOTO  Takehiro MORIYA  

     
    PAPER-Coding Theory

      Pubricized:
    2021/02/08
      Vol:
    E104-A No:8
      Page(s):
    1033-1042

    This paper presents extended-domain Golomb (XDG) code, an extension of Golomb code for sparse geometric sources as well as a generalization of extended-domain Golomb-Rice (XDGR) code, based on the idea of almost instantaneous fixed-to-variable length (AIFV) codes. Showing that the XDGR encoding can be interpreted as extended usage of the code proposed in the previous works, this paper discusses the following two facts: The proposed XDG code can be constructed as an AIFV code relating to Golomb code as XDGR code does to Rice code; XDG and Golomb codes are symmetric in the sense of relative redundancy. The proposed XDG code can be efficiently used for losslessly compressing geometric sources too sparse for the conventional Golomb and Rice codes. According to the symmetry, its relative redundancy is guaranteed to be as low as Golomb code compressing non-sparse geometric sources. Awing to this fact, the parameter of the proposed XDG code, which is more finely tunable than the conventional XDGR code, can be optimized for given inputs using the conventional techniques. Therefore, it is expected to be more useful for many coding applications that deal with geometric sources at low bit rates.

  • Video Inpainting by Frame Alignment with Deformable Convolution

    Yusuke HARA  Xueting WANG  Toshihiko YAMASAKI  

     
    PAPER-Image Processing and Video Processing

      Pubricized:
    2021/04/22
      Vol:
    E104-D No:8
      Page(s):
    1349-1358

    Video inpainting is a task of filling missing regions in videos. In this task, it is important to efficiently use information from other frames and generate plausible results with sufficient temporal consistency. In this paper, we present a video inpainting method jointly using affine transformation and deformable convolutions for frame alignment. The former is responsible for frame-scale rough alignment and the latter performs pixel-level fine alignment. Our model does not depend on 3D convolutions, which limits the temporal window, or troublesome flow estimation. The proposed method achieves improved object removal results and better PSNR and SSIM values compared with previous learning-based methods.

  • Performance Evaluation of Online Machine Learning Models Based on Cyclic Dynamic and Feature-Adaptive Time Series

    Ahmed Salih AL-KHALEEFA  Rosilah HASSAN  Mohd Riduan AHMAD  Faizan QAMAR  Zheng WEN  Azana Hafizah MOHD AMAN  Keping YU  

     
    PAPER

      Pubricized:
    2021/05/14
      Vol:
    E104-D No:8
      Page(s):
    1172-1184

    Machine learning is becoming an attractive topic for researchers and industrial firms in the area of computational intelligence because of its proven effectiveness and performance in resolving real-world problems. However, some challenges such as precise search, intelligent discovery and intelligent learning need to be addressed and solved. One most important challenge is the non-steady performance of various machine learning models during online learning and operation. Online learning is the ability of a machine-learning model to modernize information without retraining the scheme when new information is available. To address this challenge, we evaluate and analyze four widely used online machine learning models: Online Sequential Extreme Learning Machine (OSELM), Feature Adaptive OSELM (FA-OSELM), Knowledge Preserving OSELM (KP-OSELM), and Infinite Term Memory OSELM (ITM-OSELM). Specifically, we provide a testbed for the models by building a framework and configuring various evaluation scenarios given different factors in the topological and mathematical aspects of the models. Furthermore, we generate different characteristics of the time series to be learned. Results prove the real impact of the tested parameters and scenarios on the models. In terms of accuracy, KP-OSELM and ITM-OSELM are superior to OSELM and FA-OSELM. With regard to time efficiency related to the percentage of decreases in active features, ITM-OSELM is superior to KP-OSELM.

  • A Novel Multi-AP Diversity for Highly Reliable Transmissions in Wireless LANs

    Toshihisa NABETANI  Masahiro SEKIYA  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Pubricized:
    2021/01/08
      Vol:
    E104-B No:7
      Page(s):
    913-921

    With the development of the IEEE 802.11 standard for wireless LANs, there has been an enormous increase in the usage of wireless LANs in factories, plants, and other industrial environments. In industrial applications, wireless LAN systems require high reliability for stable real-time communications. In this paper, we propose a multi-access-point (AP) diversity method that contributes to the realization of robust data transmissions toward realization of ultra-reliable low-latency communications (URLLC) in wireless LANs. The proposed method can obtain a diversity effect of multipaths with independent transmission errors and collisions without modification of the IEEE 802.11 standard or increasing overhead of communication resources. We evaluate the effects of the proposed method by numerical analysis, develop a prototype to demonstrate its feasibility, and perform experiments using the prototype in a factory wireless environment. These numerical evaluations and experiments show that the proposed method increases reliability and decreases transmission delay.

  • Correlation of Centralities: A Study through Distinct Graph Robustness

    Xin-Ling GUO  Zhe-Ming LU  Yi-Jia ZHANG  

     
    LETTER-Artificial Intelligence, Data Mining

      Pubricized:
    2021/04/05
      Vol:
    E104-D No:7
      Page(s):
    1054-1057

    Robustness of complex networks is an essential subject for improving their performance when vertices or links are removed due to potential threats. In recent years, significant advancements have been achieved in this field by many researchers. In this paper we show an overview from a novel statistic perspective. We present a brief review about complex networks at first including 2 primary network models, 12 popular attack strategies and the most convincing network robustness metrics. Then, we focus on the correlations of 12 attack strategies with each other, and the difference of the correlations from one network model to the other. We are also curious about the robustness of networks when vertices are removed according to different attack strategies and the difference of robustness from one network model to the other. Our aim is to observe the correlation mechanism of centralities for distinct network models, and compare the network robustness when different centralities are applied as attacking directors to distinct network models. What inspires us is that maybe we can find a paradigm that combines several high-destructive attack strategies to find the optimal strategy based on the deep learning framework.

  • Graph Laplacian-Based Sequential Smooth Estimator for Three-Dimensional RSS Map

    Takahiro MATSUDA  Fumie ONO  Shinsuke HARA  

     
    PAPER

      Pubricized:
    2021/01/08
      Vol:
    E104-B No:7
      Page(s):
    738-748

    In wireless links between ground stations and UAVs (Unmanned Aerial Vehicles), wireless signals may be attenuated by obstructions such as buildings. A three-dimensional RSS (Received Signal Strength) map (3D-RSS map), which represents a set of RSSs at various reception points in a three-dimensional area, is a promising geographical database that can be used to design reliable ground-to-air wireless links. The construction of a 3D-RSS map requires higher computational complexity, especially for a large 3D area. In order to sequentially estimate a 3D-RSS map from partial observations of RSS values in the 3D area, we propose a graph Laplacian-based sequential smooth estimator. In the proposed estimator, the 3D area is divided into voxels, and a UAV observes the RSS values at the voxels along a predetermined path. By considering the voxels as vertices in an undirected graph, a measurement graph is dynamically constructed using vertices from which recent observations were obtained and their neighboring vertices, and the 3D-RSS map is sequentially estimated by performing graph Laplacian regularized least square estimation.

  • Complete l-Diversity Grouping Algorithm for Multiple Sensitive Attributes and Its Applications

    Yuelei XIAO  Shuang HUANG  

     
    LETTER-Cryptography and Information Security

      Pubricized:
    2021/01/12
      Vol:
    E104-A No:7
      Page(s):
    984-990

    For the first stage of the multi-sensitive bucketization (MSB) method, the l-diversity grouping for multiple sensitive attributes is incomplete, causing more information loss. To solve this problem, we give the definitions of the l-diversity avoidance set for multiple sensitive attributes and the avoiding of a multiple dimensional bucket, and propose a complete l-diversity grouping (CLDG) algorithm for multiple sensitive attributes. Then, we improve the first stages of the MSB algorithms by applying the CLDG algorithm to them. The experimental results show that the grouping ratio of the improved first stages of the MSB algorithms is significantly higher than that of the original first stages of the MSB algorithms, decreasing the information loss of the published microdata.

  • Novel Threshold Circuit Technique and Its Performance Analysis on Nanowatt Vibration Sensing Circuits for Millimeter-Sized Wireless Sensor Nodes

    Toshishige SHIMAMURA  Hiroki MORIMURA  

     
    PAPER

      Pubricized:
    2021/01/13
      Vol:
    E104-C No:7
      Page(s):
    272-279

    A new threshold circuit technique is proposed for a vibration sensing circuit that operates at a nanowatt power level. The sensing circuits that use sample-and-hold require a clock signal, and they consume power to generate a signal. In the use of a Schmitt trigger circuit that does not use a clock signal, a sink current flows when thresholding the analog signal output. The requirements for millimeter-sized wireless sensor nodes are an average power on the order of a nanowatt and a signal transition time of less than 1 ms. To meet these requirements, our circuit limits the sink current with a nanoampere-level current source. The chattering caused by current limiting is suppressed by feeding back the change in output voltage to the limiting current. The increase in the signal transition time that is caused by current limiting is reduced by accelerating the discharge of the load capacitance. For a test chip fabricated in the 0.35-µm CMOS process, the proposed threshold circuits operate without chattering and the average powers are 0.7-3 nW. The signal transition times are estimated in a circuit simulation to be 65-97 µs. The proposed circuit has 1/150th the power-delay product with no time interval of the sensing operation under the condition that the time interval is 1s. These results indicate that, the proposed threshold circuits are suitable for vibration sensing in millimeter-sized wireless sensor nodes.

  • Parameters Estimation of Impulse Noise for Channel Coded Systems over Fading Channels

    Chun-Yin CHEN  Mao-Ching CHIU  

     
    PAPER-Wireless Communication Technologies

      Pubricized:
    2021/01/18
      Vol:
    E104-B No:7
      Page(s):
    903-912

    In this paper, we propose a robust parameters estimation algorithm for channel coded systems based on the low-density parity-check (LDPC) code over fading channels with impulse noise. The estimated parameters are then used to generate bit log-likelihood ratios (LLRs) for a soft-inputLDPC decoder. The expectation-maximization (EM) algorithm is used to estimate the parameters, including the channel gain and the parameters of the Bernoulli-Gaussian (B-G) impulse noise model. The parameters can be estimated accurately and the average number of iterations of the proposed algorithm is acceptable. Simulation results show that over a wide range of impulse noise power, the proposed algorithm approaches the optimal performance under different Rician channel factors and even under Middleton class-A (M-CA) impulse noise models.

  • Room Temperature Atomic Layer Deposition of Nano Crystalline ZnO and Its Application for Flexible Electronics

    Kazuki YOSHIDA  Kentaro SAITO  Keito SOGAI  Masanori MIURA  Kensaku KANOMATA  Bashir AHMMAD  Shigeru KUBOTA  Fumihiko HIROSE  

     
    PAPER-Electronic Materials

      Pubricized:
    2020/11/26
      Vol:
    E104-C No:7
      Page(s):
    363-369

    Nano crystalline zinc oxide (ZnO) is deposited by room temperature atomic layer deposition (RT-ALD) using dimethylzinc and a plasma excited humidified Ar without thermal treatments. The TEM observation indicated that the deposited ZnO films were crystallized with grain sizes of ∼20 nm on Si in the course of the RT-ALD process. The crystalline ZnO exhibited semiconducting characteristics in a thin film transistor, where the field-effect mobility was recorded at 1.29×10-3cm2/V·s. It is confirmed that the RT deposited ZnO film has an anticorrosion to hot water. The water vapor transmission rate of 8.4×10-3g·m-2·day-1 was measured from a 20 nm thick ZnO capped 40 nm thick Al2O3 on a polyethylene naphthalate film. In this paper, we discuss the crystallization of ZnO in the RT ALD process and its applicability to flexible electronics.

  • Feedback Path-Tracking Pre-Inverse Type Active Noise Control

    Keisuke OKANO  Naoto SASAOKA  Yoshio ITOH  

     
    PAPER-Digital Signal Processing

      Pubricized:
    2020/12/28
      Vol:
    E104-A No:7
      Page(s):
    954-961

    We propose online feedback path modeling with a pre-inverse type active noise control (PIANC) system to track the fluctuation stably in the feedback path. The conventional active noise control (ANC) system with online feedback path modeling (FBPM) filter bases filtered-x least mean square (FxLMS) algorithm. In the FxLMS algorithm, the error of FBPM influences a control filter, which generates an anti-noise, and secondary path modeling (SPM) filter. The control filter diverges when the error is too large. Therefore, it is difficult for the FxLMS algorithm to track the feedback path without divergence. On the other hand, the proposed approach converges stably because the FBPM filter's error does not influence a control filter on the PIANC system. Thus, the proposed method can reduce noise while tracking the feedback path. This paper verified the effectiveness of the proposed method by convergence analysis, computer simulation, and implementation of a digital signal processor.

941-960hit(16314hit)