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1561-1580hit(42807hit)

  • High Accuracy Test Techniques with Fine Pattern Generator and Ramp Test Circuit for CMOS Image Sensor

    Fukashi MORISHITA  Wataru SAITO  Norihito KATO  Yoichi IIZUKA  Masao ITO  

     
    PAPER

      Pubricized:
    2022/01/14
      Vol:
    E105-C No:7
      Page(s):
    316-323

    This paper proposes novel test techniques for high accuracy measurement of ADCs and a ramp generator on a CMOS image sensor (CIS) chip. The test circuit for the ADCs has a dual path and has an ability of multi-functional fine pattern generator that can define any input for each column to evaluate CIS specific characteristics electrically. The test circuit for the ramp generator can realize an on-chip current cell test and reject the current cell failure within 1LSB accuracy. We fabricated the test sensor using 55nm CIS process and measured the IP characteristics. Measured results show INL of 14.6LSB, crosstalk of 14.9LSB and column interference noise of 5.4LSB. These measured results agree with the designed values. By using this technique, we confirmed the accurate ADC measurement can be realized without being affected by the ambiguity of the optical input.

  • Joint Wideband Spectrum and DOA Estimation with Compressed Sampling Based on L-Shaped Co-Prime Array

    Wanghan LV  Lihong HU  Weijun ZENG  Huali WANG  Zhangkai LUO  

     
    PAPER-Analog Signal Processing

      Pubricized:
    2022/01/21
      Vol:
    E105-A No:7
      Page(s):
    1028-1037

    As known to us all, L-shaped co-prime array (LCA) is a recently introduced two-dimensional (2-D) sparse array structure, which is extended from linear co-prime array (CA). Such sparse array geometry can be used for 2-D parameters estimation with higher degrees-of-freedom (DOF). However, in the scenario where several narrowband transmissions spread over a wide spectrum, existing technique based on LCA with Nyquist sampling may encounter a bottleneck for both analog and digital processing. To alleviate the burden of high-rate Nyquist sampling, a method of joint wideband spectrum and direction-of-arrival (DOA) estimation with compressed sampling based on LCA, which is recognized as LCA-based modulated wideband converter (MWC), is presented in this work. First, the received signal along each antenna is mixed to basebands, low-pass filtered and down-sampled to get the compressed sampling data. Then by constructing the virtual received data of 2-D difference coarray, we estimate the wideband spectrum and DOA jointly using two recovery methods where the first is a joint ESPRIT method and the other is a joint CS method. Numerical simulations illustrate the validity of the proposed LCA based MWC system and show the superiority.

  • Parameter Selection for Radar Systems in Roadside Units

    Chia-Hsing YANG  Ming-Chun LEE  Ta-Sung LEE  Hsiu-Chi CHANG  

     
    PAPER-Sensing

      Pubricized:
    2022/01/13
      Vol:
    E105-B No:7
      Page(s):
    885-892

    Intelligent transportation systems (ITSs) have been extensively studied in recent years to improve the safety and efficiency of transportation. The use of a radar system to enable the ITSs monitor the environment is robust to weather conditions and is less invasive to user privacy. Moreover, equipping the roadside units (RSUs) with radar modules has been deemed an economical and efficient option for ITS operators. However, because the detection and tracking parameters can significantly influence the radar system performance and the best parameters for different scenarios are different, the selection of appropriate parameters for the radar systems is critical. In this study, we investigated radar parameter selection and consequently proposes a parameter selection approach capable of automatically choosing the appropriate detection and tracking parameters for radar systems. The experimental results indicate that the proposed method realizes appropriate selection of parameters, thereby significantly improving the detection and tracking performance of radar systems.

  • Industry 4.0 Based Business Process Re-Engineering Framework for Manufacturing Industry Setup Incorporating Evolutionary Multi-Objective Optimization

    Anum TARIQ  Shoab AHMED KHAN  

     
    PAPER-Software Engineering

      Pubricized:
    2022/04/08
      Vol:
    E105-D No:7
      Page(s):
    1283-1295

    Manufacturers are coping with increasing pressures in quality, cost and efficiency as more and more industries are moving from traditional setup to industry 4.0 based digitally transformed setup due to its numerous playbacks. Within the manufacturing domain organizational structures and processes are complex, therefore adopting industry 4.0 and finding an optimized re-engineered business process is difficult without using a systematic methodology. Authors have developed Business Process Re-engineering (BPR) and Business Process Optimization (BPO) methods but no consolidated methodology have been seen in the literature that is based on industry 4.0 and incorporates both the BPR and BPO. We have presented a consolidated and systematic re-engineering and optimization framework for a manufacturing industry setup. The proposed framework performs Evolutionary Multi-Objective Combinatorial Optimization using Multi-Objective Genetic Algorithm (MOGA). An example process from an aircraft manufacturing factory has been optimized and re-engineered with available set of technologies from industry 4.0 based on the criteria of lower cost, reduced processing time and reduced error rate. At the end to validate the proposed framework Business Process Model and Notation (BPMN) is used for simulations and perform comparison between AS-IS and TO-BE processes as it is widely used standard for business process specification. The proposed framework will be used in converting an industry from traditional setup to industry 4.0 resulting in cost reduction, increased performance and quality.

  • Channel Arrangement Design in Lumped Amplified WDM Transmission over NZ-DSF Link with Nonlinearity Mitigation Using Optical Phase Conjugation Open Access

    Shimpei SHIMIZU  Takayuki KOBAYASHI  Takeshi UMEKI  Takushi KAZAMA  Koji ENBUTSU  Ryoichi KASAHARA  Yutaka MIYAMOTO  

     
    PAPER-Fiber-Optic Transmission for Communications

      Pubricized:
    2022/01/17
      Vol:
    E105-B No:7
      Page(s):
    805-813

    Optical phase conjugation (OPC) is an all-optical signal processing technique for mitigating fiber nonlinearity and is promising for building cost-efficient fiber networks with few optic-electric-optic conversions and long amplification spacing. In lumped amplified systems, OPC has a little nonlinearity mitigation efficiency for nonlinear distortion induced by cross-phase modulation (XPM) due to the asymmetry of power and chromatic dispersion (CD) maps during propagation in transmission fiber. In addition, the walk-off of XPM-induced noise becomes small due to the CD compensation effect of OPC, so the deterministic nonlinear distortion increases. Therefore, lumped amplified transmission systems with OPC are more sensitive to channel spacing than conventional systems. In this paper, we show the channel spacing dependence of NZ-DSF transmission using amplification repeater with OPC. Numerical simulations show comprehensive characteristics between channel spacing and CD in a 100-Gbps/λ WDM signal. An experimental verification using periodically poled LiNbO3-based OPC is also performed. These results suggest that channel spacing design is more important in OPC-assisted systems than in conventional dispersion-unmanaged systems.

  • Synchronous Sharing of Lecture Slides and Photo Messaging during Real-Time Online Classes

    Haeyoung LEE  

     
    LETTER-Educational Technology

      Pubricized:
    2022/04/21
      Vol:
    E105-D No:7
      Page(s):
    1348-1351

    This letter presents an innovative solution for real-time interaction during online classes. Synchronous sharing enables instructors to provide real-time feedback to students. This encourages students to stay focused and feel engaged during class. Consequently, students evaluated anonymously that this solution significantly enhanced their learning experience during real-time online classes.

  • A Framework for Synchronous Remote Online Exams

    Haeyoung LEE  

     
    LETTER-Educational Technology

      Pubricized:
    2022/04/22
      Vol:
    E105-D No:7
      Page(s):
    1343-1347

    This letter presents a new framework for synchronous remote online exams. This framework proposes new monitoring of notebooks in remote locations and limited messaging only enabled between students and their instructor during online exams. This framework was evaluated by students as highly effective in minimizing cheating during online exams.

  • Measurement and Ray Tracing Simulation with Urban Microcell Environments at 28GHz Band

    Hirokazu YAMAKURA  Gilbert SIY CHING  Yukiko KISHIKI  Noboru SEKINO  Ichiro OSHIMA  Tetsuro IMAI  

     
    PAPER-Propagation

      Pubricized:
    2021/12/03
      Vol:
    E105-B No:6
      Page(s):
    748-756

    In this study, we investigate outdoor propagation measurements performed in an industrial park environment at 28.3GHz band. The propagation characteristics were evaluated with the measurement result regarding the path loss characteristics. Ray tracing simulation was also studied and compared with the measurement data to evaluate the quantitative accuracy of ray tracing in millimeter-wave band wireless propagations. Ray tracing, whose accuracy was evaluated based on a comparison with the measurement results, can aid in the theoretical design of the coverage area and deterministic channel modeling.

  • Millimeter Wave SIW Cavity-Fed Filtenna Arrays for 5G Wireless Applications Open Access

    Rong LU  Chao YU  Wei HONG  

     
    INVITED PAPER

      Pubricized:
    2021/12/03
      Vol:
    E105-B No:6
      Page(s):
    707-714

    In this paper, millimeter wave (mmWave) filtenna arrays for 5G applications are proposed. Two kinds of 2-element subarrays are designed for horizontal and vertical polarizations. Each subarray consists of three substrate integrated waveguide (SIW) cavities and two sets of stacked patches. Fully-shielded combined eighth-mode SIW (FSD-CEMSIW) cavities are used in the filtenna design. This cavity not only works as the first-stage resonator but also as the power divider for the subarray. As a result, a four-order bandpass filtering response is achieved. Filtenna arrays were fabricated and measured for demonstration. The impedance bandwidths of these subarrays cover 24-30GHz, including the 5G mmWave bands (n257, n258, and n261) with measured average gains of 8.2dBi and more than 22dB out-of-band suppression. The proposed antennas can be good candidates for 5G mmWave communication to reduce the system complexity and potential cost of the mmWave front-ends.

  • Saliency Detection via Absorbing Markov Chain with Multi-Level Cues

    Pengfei LV  Xiaosheng YU  Jianning CHI  Chengdong WU  

     
    LETTER-Image

      Pubricized:
    2021/12/07
      Vol:
    E105-A No:6
      Page(s):
    1010-1014

    A robust saliency detection approach for images with a complex background is proposed. The absorbing Markov chain integrating low-level, mid-level and high-level cues dynamically evolves by using the similarity between pixels to detect saliency objects. The experimental results show that the proposed algorithm has advantages in saliency detection, especially for images with a chaotic background or low contrast.

  • FOREWORD Open Access

    Satoshi KOHJIRO  

     
    FOREWORD

      Vol:
    E105-C No:6
      Page(s):
    244-244
  • A Binary Translator to Accelerate Development of Deep Learning Processing Library for AArch64 CPU Open Access

    Kentaro KAWAKAMI  Kouji KURIHARA  Masafumi YAMAZAKI  Takumi HONDA  Naoto FUKUMOTO  

     
    PAPER

      Pubricized:
    2021/12/03
      Vol:
    E105-C No:6
      Page(s):
    222-231

    To accelerate deep learning (DL) processes on the supercomputer Fugaku, the authors have ported and optimized oneDNN for Fugaku's CPU, the Fujitsu A64FX. oneDNN is an open-source DL processing library developed by Intel for the x86_64 architecture. The A64FX CPU is based on the Armv8-A architecture. oneDNN dynamically creates the execution code for the computation kernels, which are implemented at the granularity of x86_64 instructions using Xbyak, the Just-In-Time (JIT) assembler for x86_64 architecture. To port oneDNN to A64FX, it must be rewritten into Armv8-A instructions using Xbyak_aarch64, the JIT assembler for the Armv8-A architecture. This is challenging because the number of steps to be rewritten exceeds several tens of thousands of lines. This study presents the Xbyak_translator_aarch64. Xbyak_translator_aarch64 is a binary translator that at runtime converts dynamically produced executable codes for the x86_64 architecture into executable codes for the Armv8-A architecture. Xbyak_translator_aarch64 eliminates the need to rewrite the source code for porting oneDNN to A64FX and allows us to port oneDNN to A64FX quickly.

  • Spatial-Temporal Regularized Correlation Filter with Precise State Estimation for Visual Tracking

    Zhaoqian TANG  Kaoru ARAKAWA  

     
    PAPER-Digital Signal Processing

      Pubricized:
    2021/12/15
      Vol:
    E105-A No:6
      Page(s):
    914-922

    Recently, the performances of discriminative correlation filter (CF) trackers are getting better and better in visual tracking. In this paper, we propose spatial-temporal regularization with precise state estimation based on discriminative correlation filter (STPSE) in order to achieve more significant tracking performance. First, we consider the continuous change of the object state, using the information from the previous two filters for training the correlation filter model. Here, we train the correlation filter model with the hand-crafted features. Second, we introduce update control in which average peak-to-correlation energy (APCE) and the distance between the object locations obtained by HOG features and hand-crafted features are utilized to detect abnormality of the state around the object. APCE and the distance indicate the reliability of the filter response, thus if abnormality is detected, the proposed method does not update the scale and the object location estimated by the filter response. In the experiment, our tracker (STPSE) achieves significant and real-time performance with only CPU for the challenging benchmark sequence (OTB2013, OTB2015, and TC128).

  • Complex Frequency Domain Analysis of Memristor Based on Volterra Series Open Access

    Qinghua WANG  Shiying JIA  

     
    PAPER-Circuit Theory

      Pubricized:
    2021/12/17
      Vol:
    E105-A No:6
      Page(s):
    923-929

    At present, the application of different types of memristors in electronics is being deeply studied. Given the nonlinearity characterizing memristors, a circuit with memristors cannot be treated by classical circuit analysis. In this paper, memristor is equivalent to a nonlinear dynamic system composed of linear dynamic system and nonlinear static system by Volterra series. The nonlinear transfer function of memristor is derived. In the complex frequency domain, the n-order complex frequency response of memristor is established by multiple Laplace transform, and the response of MLC parallel circuit is taken as an example to verify. Theoretical analysis shows that the complex frequency domain analysis method of memristor transforms the problem of solving nonlinear circuit in time domain into n times complex frequency domain analysis of linear circuit, which provides an idea for nonlinear dynamic system analysis.

  • An Improved Adaptive Algorithm for Locating Faulty Interactions in Combinatorial Testing Open Access

    Qianqian YANG  Xiao-Nan LU  

     
    PAPER-Algorithms and Data Structures

      Pubricized:
    2021/11/29
      Vol:
    E105-A No:6
      Page(s):
    930-942

    Combinatorial testing is an effective testing technique for detecting faults in a software or hardware system with multiple factors using combinatorial methods. By performing a test, which is an assignment of possible values to all the factors, and verifying whether the system functions as expected (pass) or not (fail), the presence of faults can be detected. The failures of the tests are possibly caused by combinations of multiple factors assigned with specific values, called faulty interactions. Martínez et al. [1] proposed the first deterministic adaptive algorithm for discovering faulty interactions involving at most two factors where each factor has two values, for which graph representations are adopted. In this paper, we improve Martínez et al.'s algorithm by an adaptive algorithmic approach for discovering faulty interactions in the so-called “non-2-locatable” graphs. We show that, for any system where each “non-2-locatable factor-component” involves two faulty interactions (for example, a system having at most two faulty interactions), our improved algorithm efficiently discovers all the faulty interactions with an extremely low mistaken probability caused by the random selection process in Martínez et al.'s algorithm. The effectiveness of our improved algorithm are revealed by both theoretical discussions and experimental evaluations.

  • Number of Failed Components in Consecutive-k-out-of-n:G Systems and Their Applications in Optimization Problems

    Lei ZHOU  Hisashi YAMAMOTO  

     
    PAPER-Reliability, Maintainability and Safety Analysis

      Pubricized:
    2021/12/16
      Vol:
    E105-A No:6
      Page(s):
    943-951

    In this paper, we study the number of failed components in a consecutive-k-out-of-n:G system. The distributions and expected values of the number of failed components when system is failed or working at a particular time t are evaluated. We also apply them to the optimization problems concerned with the optimal number of components and the optimal replacement time. Finally, we present the illustrative examples for the expected number of failed components and give the numerical results for the optimization problems.

  • Vulnerability — Information Leakage of Reused Secret Key in NewHope

    Routo TERADA  Reynaldo CACERES VILLENA  

     
    PAPER-Cryptography and Information Security

      Pubricized:
    2021/12/06
      Vol:
    E105-A No:6
      Page(s):
    952-964

    The NIST post-quantum project intends to standardize cryptographic systems that are secure against attacks by both quantum and classical computers. One of these cryptographic systems is NewHope that is a RING-LWE based key exchange scheme. The NewHope Key Encapsulation Method (KEM) allows to establish an encapsulated (secret) key shared by two participants. This scheme defines a private key that is used to encipher a random shared secret and the private key enables the deciphering. This paper presents Fault Information Leakage attacks, using conventional personal computers, if the attacked participant, say Bob, reuses his public key. This assumption is not so strong since reusing the pair (secret, public) keys saves Bob's device computing cost when the public global parameter is not changed. With our result we can conclude that, to prevent leakage, Bob should not reuse his NewHope secret and public keys because Bob's secret key can be retrieved with only 2 communications. We also found that Bob's secret keys can be retrieved for NewHopeToy2, NewHopeToy1 and NewHopeLudicrous with 1, 2, and 3 communications, respectively.

  • A Cost-Sensitive Golden Chip-Free Hardware Trojan Detection Using Principal Component Analysis and Naïve Bayes Classification Algorithm

    Yanjiang LIU  Xianzhao XIA  Jingxin ZHONG  Pengfei GUO  Chunsheng ZHU  Zibin DAI  

     
    PAPER-Cryptography and Information Security

      Pubricized:
    2021/12/03
      Vol:
    E105-A No:6
      Page(s):
    965-974

    Side-channel analysis is one of the most investigated hardware Trojan detection approaches. However, nearly all the side-channel analysis approaches require golden chips for reference, which are hard to obtain actually. Besides, majority of existing Trojan detection algorithms focus on the data similarity and ignore the Trojan misclassification during the detection. In this paper, we propose a cost-sensitive golden chip-free hardware Trojan detection framework, which aims to minimize the probability of Trojan misclassification during the detection. The post-layout simulation data of voltage variations at different process corners is utilized as a golden reference. Further, a classification algorithm based on the combination of principal component analysis and Naïve bayes is exploited to identify the existence of hardware Trojan with a minimum misclassification risk. Experimental results on ASIC demonstrate that the proposed approach improves the detection accuracy ratio compared with the three detection algorithms and distinguishes the Trojan with only 0.27% area occupies even under ±15% process variations.

  • Variable Tap-Length Algorithm Based on a Mixed Error Cost Function

    Yufei HAN  Yibo LI  Yao LI  

     
    LETTER-Digital Signal Processing

      Pubricized:
    2021/12/17
      Vol:
    E105-A No:6
      Page(s):
    1006-1009

    Numerous variable tap-length algorithms can be found in some literature and few strategies are derived from a basic theoretical formula. Thus, some algorithms lack of theoretical depth and their performance are unstable. In view of this point, the novel variable tap-length algorithm which is based on the mixed error cost function is presented in this letter. By analyzing the mixed expectation of the prior and the posterior error, the novel variable tap-length strategy is derived. The proposed algorithm has a more valid proximity to the optimal tap-length and a good convergence ability by the performance analysis. It can solve many deficiencies comprising large fluctuations of the tap-length, the high complexity and the weak steady-state ability. Simulation results demonstrate that the proposed algorithm equips good performance.

  • Rain Attenuation Characteristics due to Typhoon Wind Velocities in Satellite Communications Open Access

    Yasuyuki MAEKAWA  Yoshiaki SHIBAGAKI  

     
    PAPER-Propagation

      Pubricized:
    2021/12/03
      Vol:
    E105-B No:6
      Page(s):
    757-765

    Rain attenuation characteristics due to typhoon passage are discussed using the Ku-band BS satellite signal observations conducted by Osaka Electro-Communication University in Neayagawa from 1988 to 2019. The degree of hourly rain attenuation due to rainfall rate is largely enhanced as typhoon passes the east side of the station, while it becomes smaller in the case of west side passage. Compared to hourly ground wind velocities of nearby AMeDAS, the equivalent path lengths of rain attenuation become larger as the wind directions approach the same angle to the satellite, while they become smaller as the wind directions approach the opposite angle to the satellite. The increase and decrease of the equivalent path lengths are confirmed in other Ku-band and Ka-band satellite paths with different azimuth angles, such as CS, SKP, and SBC. Modified equivalent path lengths calculated by a simple propagation path model including horizontal wind speeds along the same direction to the satellite agree well with the equivalent path lengths observed by each satellite. The equivalent path lengths are, for the first time, proved to be largely affected by the direction of typhoon passage and the horizontal wind velocities.

1561-1580hit(42807hit)