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[Keyword] CTI(8214hit)

241-260hit(8214hit)

  • Security Evaluation of Initialization Phases and Round Functions of Rocca and AEGIS

    Nobuyuki TAKEUCHI  Kosei SAKAMOTO  Takanori ISOBE  

     
    PAPER

      Pubricized:
    2022/11/09
      Vol:
    E106-A No:3
      Page(s):
    253-262

    Authenticated-Encryption with Associated-Data (AEAD) plays an important role in guaranteeing confidentiality, integrity, and authenticity in network communications. To meet the requirements of high-performance applications, several AEADs make use of AES New Instructions (AES-NI), which can conduct operations of AES encryption and decryption dramatically fast by hardware accelerations. At SAC 2013, Wu and Preneel proposed an AES-based AEAD scheme called AEGIS-128/128L/256, to achieve high-speed software implementation. At FSE 2016, Jean and Nikolić generalized the construction of AEGIS and proposed more efficient round functions. At ToSC 2021, Sakamoto et al. further improved the constructions of Jean and Nikolić, and proposed an AEAD scheme called Rocca for beyond 5G. In this study, we first evaluate the security of the initialization phases of Rocca and AEGIS family against differential and integral attacks using MILP (Mixed Integer Linear Programming) tools. Specifically, according to the evaluation based on the lower bounds for the number of active S-boxes, the initialization phases of AEGIS-128/128L/256 are secure against differential attacks after 4/3/6 rounds, respectively. Regarding integral attacks, we present the integral distinguisher on 6 rounds and 6/5/7 rounds in the initialization phases of Rocca and AEGIS-128/128L/256, respectively. Besides, we evaluate the round function of Rocca and those of Jean and Nikolić as cryptographic permutations against differential, impossible differential, and integral attacks. Our results indicate that, for differential attacks, the growth rate of increasing the number of active S-boxes in Rocca is faster than those of Jean and Nikolić. For impossible differential and integral attacks, we show that the round function of Rocca achieves the sufficient level of the security against these attacks in smaller number of rounds than those of Jean and Nikolić.

  • On the Limitations of Computational Fuzzy Extractors

    Kenji YASUNAGA  Kosuke YUZAWA  

     
    LETTER

      Pubricized:
    2022/08/10
      Vol:
    E106-A No:3
      Page(s):
    350-354

    We present a negative result of fuzzy extractors with computational security. Specifically, we show that, under a computational condition, a computational fuzzy extractor implies the existence of an information-theoretic fuzzy extractor with slightly weaker parameters. Our result implies that to circumvent the limitations of information-theoretic fuzzy extractors, we need to employ computational fuzzy extractors that are not invertible by non-lossy functions.

  • Multi Deletion/Substitution/Erasure Error-Correcting Codes for Information in Array Design

    Manabu HAGIWARA  

     
    PAPER-Coding Theory and Techniques

      Pubricized:
    2022/09/21
      Vol:
    E106-A No:3
      Page(s):
    368-374

    This paper considers error-correction for information in array design, i.e., two-dimensional design such as QR-codes. The error model is multi deletion/substitution/erasure errors. Code construction for the errors and an application of the code are provided. The decoding technique uses an error-locator for deletion codes.

  • Asymptotic Evaluation of Classification in the Presence of Label Noise

    Goki YASUDA  Tota SUKO  Manabu KOBAYASHI  Toshiyasu MATSUSHIMA  

     
    PAPER-Learning

      Pubricized:
    2022/08/26
      Vol:
    E106-A No:3
      Page(s):
    422-430

    In a practical classification problem, there are cases where incorrect labels are included in training data due to label noise. We introduce a classification method in the presence of label noise that idealizes a classification method based on the expectation-maximization (EM) algorithm, and evaluate its performance theoretically. Its performance is asymptotically evaluated by assessing the risk function defined as the Kullback-Leibler divergence between predictive distribution and true distribution. The result of this performance evaluation enables a theoretical evaluation of the most successful performance that the EM-based classification method may achieve.

  • Enumeration of Both-Ends-Fixed k-Ary Necklaces and Its Applications

    Hiroshi FUJISAKI  

     
    PAPER-Fundamentals of Information Theory

      Pubricized:
    2022/08/23
      Vol:
    E106-A No:3
      Page(s):
    431-439

    We consider both-ends-fixed k-ary necklaces and enumerate all such necklaces of length n from the viewpoints of symbolic dynamics and β-expansions, where n and k(≥ 2) are natural numbers and β(> 1) is a real number. Recently, Sawada et al. proposed an efficient construction of k-ary de Bruijn sequence of length kn, which for each n ≥ 1, requires O(n) space but generates a single k-ary de Bruijn sequence of length kn in O(1)-amortized time per bit. Based on the enumeration of both-ends-fixed k-ary necklaces of length n, we evaluate auto-correlation values of the k-ary de Bruijn sequences of length kn constructed by Sawada et al. We also estimate the asymptotic behaviour of the obtained auto-correlation values as n tends to infinity.

  • New Performance Evaluation Method for Data Embedding Techniques for Printed Images Using Mobile Devices Based on a GAN

    Masahiro YASUDA  Soh YOSHIDA  Mitsuji MUNEYASU  

     
    LETTER

      Pubricized:
    2022/08/23
      Vol:
    E106-A No:3
      Page(s):
    481-485

    Methods that embed data into printed images and retrieve data from printed images captured using the camera of a mobile device have been proposed. Evaluating these methods requires printing and capturing actual embedded images, which is burdensome. In this paper, we propose a method for reducing the workload for evaluating the performance of data embedding algorithms by simulating the degradation caused by printing and capturing images using generative adversarial networks. The proposed method can represent various captured conditions. Experimental results demonstrate that the proposed method achieves the same accuracy as detecting embedded data under actual conditions.

  • Analytical Minimization of L2-Sensitivity for All-Pass Fractional Delay Digital Filters with Normalized Lattice Structure

    Shunsuke KOSHITA  

     
    LETTER

      Pubricized:
    2022/08/24
      Vol:
    E106-A No:3
      Page(s):
    486-489

    This letter theoretically analyzes and minimizes the L2-sensitivity for all-pass fractional delay digital filters of which structure is given by the normalized lattice structure. The L2-sensitivity is well known as one of the useful evaluation functions for measuring the performance degradation caused by quantizing filter coefficients into finite number of bits. This letter deals with two cases: L2-sensitivity minimization problem with scaling constraint, and the one without scaling constraint. It is proved that, in both of these two cases, any all-pass fractional delay digital filter with the normalized lattice structure becomes an optimal structure that analytically minimizes the L2-sensitivity.

  • Vulnerability Estimation of DNN Model Parameters with Few Fault Injections

    Yangchao ZHANG  Hiroaki ITSUJI  Takumi UEZONO  Tadanobu TOBA  Masanori HASHIMOTO  

     
    PAPER

      Pubricized:
    2022/11/09
      Vol:
    E106-A No:3
      Page(s):
    523-531

    The reliability of deep neural networks (DNN) against hardware errors is essential as DNNs are increasingly employed in safety-critical applications such as automatic driving. Transient errors in memory, such as radiation-induced soft error, may propagate through the inference computation, resulting in unexpected output, which can adversely trigger catastrophic system failures. As a first step to tackle this problem, this paper proposes constructing a vulnerability model (VM) with a small number of fault injections to identify vulnerable model parameters in DNN. We reduce the number of bit locations for fault injection significantly and develop a flow to incrementally collect the training data, i.e., the fault injection results, for VM accuracy improvement. We enumerate key features (KF) that characterize the vulnerability of the parameters and use KF and the collected training data to construct VM. Experimental results show that VM can estimate vulnerabilities of all DNN model parameters only with 1/3490 computations compared with traditional fault injection-based vulnerability estimation.

  • An Accuracy Reconfigurable Vector Accelerator based on Approximate Logarithmic Multipliers for Energy-Efficient Computing

    Lingxiao HOU  Yutaka MASUDA  Tohru ISHIHARA  

     
    PAPER

      Pubricized:
    2022/09/02
      Vol:
    E106-A No:3
      Page(s):
    532-541

    The approximate logarithmic multiplier proposed by Mitchell provides an efficient alternative for processing dense multiplication or multiply-accumulate operations in applications such as image processing and real-time robotics. It offers the advantages of small area, high energy efficiency and is suitable for applications that do not necessarily achieve high accuracy. However, its maximum error of 11.1% makes it challenging to deploy in applications requiring relatively high accuracy. This paper proposes a novel operand decomposition method (OD) that decomposes one multiplication into the sum of multiple approximate logarithmic multiplications to widely reduce Mitchell multiplier errors while taking full advantage of its area savings. Based on the proposed OD method, this paper also proposes an accuracy reconfigurable multiply-accumulate (MAC) unit that provides multiple reconfigurable accuracies with high parallelism. Compared to a MAC unit consisting of accurate multipliers, the area is significantly reduced to less than half, improving the hardware parallelism while satisfying the required accuracy for various scenarios. The experimental results show the excellent applicability of our proposed MAC unit in image smoothing and robot localization and mapping application. We have also designed a prototype processor that integrates the minimum functionality of this MAC unit as a vector accelerator and have implemented a software-level accuracy reconfiguration in the form of an instruction set extension. We experimentally confirmed the correct operation of the proposed vector accelerator, which provides the different degrees of accuracy and parallelism at the software level.

  • On the Number of Affine Equivalence Classes of Vectorial Boolean Functions and q-Ary Functions

    Shihao LU  Haibin KAN  Jie PENG  Chenmiao SHI  

     
    PAPER-Cryptography and Information Security

      Pubricized:
    2022/08/24
      Vol:
    E106-A No:3
      Page(s):
    600-605

    Vectorial Boolean functions play an important role in cryptography, sequences and coding theory. Both affine equivalence and EA-equivalence are well known equivalence relations between vectorial Boolean functions. In this paper, we give an exact formula for the number of affine equivalence classes, and an asymptotic formula for the number of EA-equivalence classes of vectorial Boolean functions.

  • Double-Directional Time-Spatial Measurement Method Using Synthetic Aperture Antenna

    Kazuma TOMIMOTO  Ryo YAMAGUCHI  Takeshi FUKUSAKO  

     
    PAPER-Antennas and Propagation

      Pubricized:
    2022/09/21
      Vol:
    E106-B No:3
      Page(s):
    250-259

    The 5th-generation mobile communication uses multi-element array antennas in not only base stations but also mobile terminals. In order to design multi-element array antennas efficiently, it is important to acquire the characteristics of the direction of arrival (DOA) and direction of departure (DOD), and a highly accurate and simple measurement method is required. This paper proposes a highly accurate and simple method to measure DOA and DOD by applying synthetic aperture (SA) processed at both Rx and Tx sides. It is also shown that the addition of beam scanning to the proposed method can reduce the measurement time while maintaining the peak detection resolution. Moreover, experiments in an anechoic chamber and a shielded room using actual wave sources confirm that DOA and DOD can be detected with high accuracy.

  • iMon: Network Function Virtualisation Monitoring Based on a Unique Agent

    Cong ZHOU  Jing TAO  Baosheng WANG  Na ZHAO  

     
    PAPER-Network

      Pubricized:
    2022/09/21
      Vol:
    E106-B No:3
      Page(s):
    230-240

    As a key technology of 5G, NFV has attracted much attention. In addition, monitoring plays an important role, and can be widely used for virtual network function placement and resource optimisation. The existing monitoring methods focus on the monitoring load without considering they own resources needed. This raises a unique challenge: jointly optimising the NFV monitoring systems and minimising their monitoring load at runtime. The objective is to enhance the gain in real-time monitoring metrics at minimum monitoring costs. In this context, we propose a novel NFV monitoring solution, namely, iMon (Monitoring by inferring), that jointly optimises the monitoring process and reduces resource consumption. We formalise the monitoring process into a multitarget regression problem and propose three regression models. These models are implemented by a deep neural network, and an experimental platform is built to prove their availability and effectiveness. Finally, experiments also show that monitoring resource requirements are reduced, and the monitoring load is just 0.6% of that of the monitoring tool cAdvisor on our dataset.

  • A Novel Unambiguous Acquisition Algorithm Based on Segmentation Reconstruction for BOC(n,n) Signal Open Access

    Yuanfa JI  Sisi SONG  Xiyan SUN  Ning GUO  Youming LI  

     
    PAPER-Navigation, Guidance and Control Systems

      Pubricized:
    2022/08/26
      Vol:
    E106-B No:3
      Page(s):
    287-295

    In order to improve the frequency band utilization and avoid mutual interference between signals, the BD3 satellite signals adopt Binary Offset Carrier (BOC) modulation. On one hand, BOC modulation has a narrow main peak width and strong anti-interference ability; on the other hand, the phenomenon of false acquisition locking caused by the multi-peak characteristic of BOC modulation itself needs to be resolved. In this context, this paper proposes a new BOC(n,n) unambiguous acquisition algorithm based on segmentation reconstruction. The algorithm is based on splitting the local BOC signal into four parts in each subcarrier period. The branch signal and the received signal are correlated with the received signal to generate four branch correlation signals. After a series of combined reconstructions, the final signal detection function completely eliminates secondary peaks. A simulation shows that the algorithm can completely eliminate the sub-peak interference for the BOC signals modulated by subcarriers with different phase. The characteristics of narrow correlation peak are retained. Experiments show that the proposed algorithm has superior performance in detection probability and peak-to-average ratio.

  • Theoretical and Experimental Analysis of the Spurious Modes and Quality Factors for Dual-Mode AlN Lamb-Wave Resonators

    Haiyan SUN  Xingyu WANG  Zheng ZHU  Jicong ZHAO  

     
    PAPER-Ultrasonic Electronics

      Pubricized:
    2022/08/10
      Vol:
    E106-C No:3
      Page(s):
    76-83

    In this paper, the spurious modes and quality-factor (Q) values of the one-port dual-mode AlN lamb-wave resonators at 500-1000 MHz were studied by theoretical analysis and experimental verification. Through finite element analysis, we found that optimizing the width of the lateral reflection boundary at both ends of the resonator to reach the quarter wavelength (λ/4), which can improve its spectral purity and shift its resonant frequency. The designed resonators were micro-fabricated by using lithography processes on a 6-inch wafer. The measured results show that the spurious mode can be converted and dissipated, splitting into several longitudinal modes by optimizing the width of the lateral reflection boundary, which are consistent well with the theoretical analysis. Similarly, optimizing the interdigital transducer (IDT) width and number of IDT fingers can also suppress the resonator's spurious modes. In addition, it is found that there is no significant difference in the Qs value for the two modes of the dual-mode resonator with the narrow anchor and full anchor. The acoustic wave leaked from the anchor into the substrate produces a small displacement, and the energy is limited in the resonator. Compared to the resonator with Au IDTs, the resonator with Al IDTs can achieve a higher Q value due to its lower thermo-elastic damping loss. The measured results show the optimized dual-mode lamb-wave resonator can obtain Qs value of 2946.3 and 2881.4 at 730.6 MHz and 859.5 MHz, Qp values of 632.5 and 1407.6, effective electromechanical coupling coefficient (k2eff) of 0.73% and 0.11% respectively, and has excellent spectral purity simultaneously.

  • An Interactive and Reductive Graph Processing Library for Edge Computing in Smart Society

    Jun ZHOU  Masaaki KONDO  

     
    PAPER

      Pubricized:
    2022/11/07
      Vol:
    E106-D No:3
      Page(s):
    319-327

    Due to the limitations of cloud computing on latency, bandwidth and data confidentiality, edge computing has emerged as a novel location-aware paradigm to provide them with more processing capacity to improve the computing performance and quality of service (QoS) in several typical domains of human activity in smart society, such as social networks, medical diagnosis, telecommunications, recommendation systems, internal threat detection, transports, Internet of Things (IoT), etc. These application domains often handle a vast collection of entities with various relationships, which can be naturally represented by the graph data structure. Graph processing is a powerful tool to model and optimize complex problems in which the graph-based data is involved. In view of the relatively insufficient resource provisioning of the portable terminals, in this paper, for the first time to our knowledge, we propose an interactive and reductive graph processing library (GPL) for edge computing in smart society at low overhead. Experimental evaluation is conducted to indicate that the proposed GPL is more user-friendly and highly competitive compared with other established systems, such as igraph, NetworKit and NetworkX, based on different graph datasets over a variety of popular algorithms.

  • Split and Eliminate: A Region-Based Segmentation for Hardware Trojan Detection

    Ann Jelyn TIEMPO  Yong-Jin JEONG  

     
    PAPER-Dependable Computing

      Pubricized:
    2022/12/09
      Vol:
    E106-D No:3
      Page(s):
    349-356

    Using third-party intellectual properties (3PIP) has been a norm in IC design development process to meet the time-to-market demand and at the same time minimizing the cost. But this flow introduces a threat, such as hardware trojan, which may compromise the security and trustworthiness of underlying hardware, like disclosing confidential information, impeding normal execution and even permanent damage to the system. In years, different detections methods are explored, from just identifying if the circuit is infected with hardware trojan using conventional methods to applying machine learning where it identifies which nets are most likely are hardware trojans. But the performance is not satisfactory in terms of maximizing the detection rate and minimizing the false positive rate. In this paper, a new hardware trojan detection approach is proposed where gate-level netlist is segmented into regions first before analyzing which nets might be hardware trojans. The segmentation process depends on the nets' connectivity, more specifically by looking on each fanout points. Then, further analysis takes place by means of computing the structural similarity of each segmented region and differentiate hardware trojan nets from normal nets. Experimental results show 100% detection of hardware trojan nets inserted on each benchmark circuits and an overall average of 1.38% of false positive rates which resulted to a higher accuracy with an average of 99.31%.

  • Acoustic HMMs to Detect Abnormal Respiration with Limited Training Data

    Masaru YAMASHITA  

     
    PAPER-Pattern Recognition

      Pubricized:
    2022/12/19
      Vol:
    E106-D No:3
      Page(s):
    374-380

    In many situations, abnormal sounds, called adventitious sounds, are included with the lung sounds of a subject suffering from pulmonary diseases. Thus, a method to automatically detect abnormal sounds in auscultation was proposed. The acoustic features of normal lung sounds for control subjects and abnormal lung sounds for patients are expressed using hidden markov models (HMMs) to distinguish between normal and abnormal lung sounds. Furthermore, abnormal sounds were detected in a noisy environment, including heart sounds, using a heart-sound model. However, the F1-score obtained in detecting abnormal respiration was low (0.8493). Moreover, the duration and acoustic properties of segments of respiratory, heart, and adventitious sounds varied. In our previous method, the appropriate HMMs for the heart and adventitious sound segments were constructed. Although the properties of the types of adventitious sounds varied, an appropriate topology for each type was not considered. In this study, appropriate HMMs for the segments of each type of adventitious sound and other segments were constructed. The F1-score was increased (0.8726) by selecting a suitable topology for each segment. The results demonstrate the effectiveness of the proposed method.

  • Learning Multi-Level Features for Improved 3D Reconstruction

    Fairuz SAFWAN MAHAD  Masakazu IWAMURA  Koichi KISE  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2022/12/08
      Vol:
    E106-D No:3
      Page(s):
    381-390

    3D reconstruction methods using neural networks are popular and have been studied extensively. However, the resulting models typically lack detail, reducing the quality of the 3D reconstruction. This is because the network is not designed to capture the fine details of the object. Therefore, in this paper, we propose two networks designed to capture both the coarse and fine details of the object to improve the reconstruction of the detailed parts of the object. To accomplish this, we design two networks. The first network uses a multi-scale architecture with skip connections to associate and merge features from other levels. For the second network, we design a multi-branch deep generative network that separately learns the local features, generic features, and the intermediate features through three different tailored components. In both network architectures, the principle entails allowing the network to learn features at different levels that can reconstruct the fine parts and the overall shape of the reconstructed 3D model. We show that both of our methods outperformed state-of-the-art approaches.

  • Object-ABN: Learning to Generate Sharp Attention Maps for Action Recognition

    Tomoya NITTA  Tsubasa HIRAKAWA  Hironobu FUJIYOSHI  Toru TAMAKI  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2022/12/14
      Vol:
    E106-D No:3
      Page(s):
    391-400

    In this paper we propose an extension of the Attention Branch Network (ABN) by using instance segmentation for generating sharper attention maps for action recognition. Methods for visual explanation such as Grad-CAM usually generate blurry maps which are not intuitive for humans to understand, particularly in recognizing actions of people in videos. Our proposed method, Object-ABN, tackles this issue by introducing a new mask loss that makes the generated attention maps close to the instance segmentation result. Further the Prototype Conformity (PC) loss and multiple attention maps are introduced to enhance the sharpness of the maps and improve the performance of classification. Experimental results with UCF101 and SSv2 shows that the generated maps by the proposed method are much clearer qualitatively and quantitatively than those of the original ABN.

  • DFAM-DETR: Deformable Feature Based Attention Mechanism DETR on Slender Object Detection

    Feng WEN  Mei WANG  Xiaojie HU  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2022/12/09
      Vol:
    E106-D No:3
      Page(s):
    401-409

    Object detection is one of the most important aspects of computer vision, and the use of CNNs for object detection has yielded substantial results in a variety of fields. However, due to the fixed sampling in standard convolution layers, it restricts receptive fields to fixed locations and limits CNNs in geometric transformations. This leads to poor performance of CNNs for slender object detection. In order to achieve better slender object detection accuracy and efficiency, this proposed detector DFAM-DETR not only can adjust the sampling points adaptively, but also enhance the ability to focus on slender object features and extract essential information from global to local on the image through an attention mechanism. This study uses slender objects images from MS-COCO dataset. The experimental results show that DFAM-DETR achieves excellent detection performance on slender objects compared to CNN and transformer-based detectors.

241-260hit(8214hit)