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  • Research on the Switch Migration Strategy Based on Global Optimization Open Access

    Xiao’an BAO  Shifan ZHOU  Biao WU  Xiaomei TU  Yuting JIN  Qingqi ZHANG  Na ZHANG  

     
    PAPER-Information Network

      Pubricized:
    2024/03/25
      Vol:
    E107-D No:7
      Page(s):
    825-834

    With the popularization of software defined networks, switch migration as an important network management strategy has attracted increasing attention. Most existing switch migration strategies only consider local conditions and simple load thresholds, without fully considering the overall optimization and dynamics of the network. Therefore, this article proposes a switch migration algorithm based on global optimization. This algorithm adds a load prediction module to the migration model, determines the migration controller, and uses an improved whale optimization algorithm to determine the target controller and its surrounding controller set. Based on the load status of the controller and the traffic priority of the switch to be migrated, the optimal migration switch set is determined. The experimental results show that compared to existing schemes, the algorithm proposed in this paper improves the average flow processing efficiency by 15% to 40%, reduces switch migration times, and enhances the security of the controller.

  • A Multiobjective Approach for Side-Channel Based Hardware Trojan Detection Using Power Traces Open Access

    Priyadharshini MOHANRAJ  Saravanan PARAMASIVAM  

     
    PAPER-Cryptography and Information Security

      Pubricized:
    2023/08/23
      Vol:
    E107-A No:5
      Page(s):
    825-835

    The detection of hardware trojans has been extensively studied in the past. In this article, we propose a side-channel analysis technique that uses a wrapper-based feature selection technique for hardware trojan detection. The whale optimization algorithm is modified to carefully extract the best feature subset. The aim of the proposed technique is multiobjective: improve the accuracy and minimize the number of features. The power consumption traces measured from AES-128 trojan circuits are used as features in this experiment. The stabilizing property of the feature selection method helps to bring a mutual trade-off between the precision and recall parameters thereby minimizing the number of false negatives. The proposed hardware trojan detection scheme produces a maximum of 10.3% improvement in accuracy and reduction up to a single feature by employing the modified whale optimization technique. Thus the evaluation results conducted on various trust-hub cryptographic benchmark circuits prove to be efficient from the existing state-of-art methods.

  • Persymmetric Structured Covariance Matrix Estimation Based on Whitening for Airborne STAP

    Quanxin MA  Xiaolin DU  Jianbo LI  Yang JING  Yuqing CHANG  

     
    LETTER-Digital Signal Processing

      Pubricized:
    2022/12/27
      Vol:
    E106-A No:7
      Page(s):
    1002-1006

    The estimation problem of structured clutter covariance matrix (CCM) in space-time adaptive processing (STAP) for airborne radar systems is studied in this letter. By employing the prior knowledge and the persymmetric covariance structure, a new estimation algorithm is proposed based on the whitening ability of the covariance matrix. The proposed algorithm is robust to prior knowledge of different accuracy, and can whiten the observed interference data to obtain the optimal solution. In addition, the extended factored approach (EFA) is used in the optimization for dimensionality reduction, which reduces the computational burden. Simulation results show that the proposed algorithm can effectively improve STAP performance even under the condition of some errors in prior knowledge.

  • Ultra-Low-Latency 8K-Video-Transmission System Utilizing Whitebox Transponder with Disaggregation Configuration

    Yasuhiro MOCHIDA  Daisuke SHIRAI  Koichi TAKASUGI  

     
    PAPER

      Pubricized:
    2022/12/16
      Vol:
    E106-C No:6
      Page(s):
    321-330

    The demand for low-latency transmission of large-capacity video, such as 4K and 8K, is increasing for various applications such as live-broadcast program production, sports viewing, and medical care. In the broadcast industry, low-latency video transmission is required in remote production, an emerging workflow for outside broadcasting. For ideal remote production, long-distance transmission of uncompressed 8K60p video signals, ultra-low latency less than 16.7 ms, and PTP synchronization through network are required; however, no existing video-transmission system fully satisfy these requirements. We focused on optical transport technologies capable of long-distance and large-capacity communication, which were previously used only in telecommunication-carrier networks. To fully utilize optical transport technologies, we propose the first-ever video-transmission system architecture capable of sending and receiving uncompressed 8K video directly through large-capacity optical paths. A transmission timing control in seamless protection switching is also proposed to improve the tolerance to network impairment. As a means of implementation, we focused on whitebox transponder, an emerging type of optical transponder with a disaggregation configuration. The disaggregation configuration enables flexible configuration changes, additional implementations, and cost reduction by separating various functions of optical transponders and controlling them with a standardized interface. We implemented the ultra-low-latency video-transmission system utilizing whitebox transponder Galileo. We developed a hardware plug-in unit for video transmission (VideoPIU), and software to control the VideoPIU. In the video-transmission experiments with 120-km optical fiber, we confirmed that it was capable of transmitting uncompressed 8K60p video stably in 1.3 ms latency and highly accurate PTP synchronization through the optical network, which was required in the ideal remote production. In addition, the application to immersive sports viewing is also presented. Consequently, excellent potential to support the unprecedented applications is demonstrated.

  • The Effectiveness of Data Augmentation for Mature White Blood Cell Image Classification in Deep Learning — Selection of an Optimal Technique for Hematological Morphology Recognition —

    Hiroyuki NOZAKA  Kosuke KAMATA  Kazufumi YAMAGATA  

     
    PAPER-Smart Healthcare

      Pubricized:
    2022/11/22
      Vol:
    E106-D No:5
      Page(s):
    707-714

    The data augmentation method is known as a helpful technique to generate a dataset with a large number of images from one with a small number of images for supervised training in deep learning. However, a low validity augmentation method for image recognition was reported in a recent study on artificial intelligence (AI). This study aimed to clarify the optimal data augmentation method in deep learning model generation for the recognition of white blood cells (WBCs). Study Design: We conducted three different data augmentation methods (rotation, scaling, and distortion) on original WBC images, with each AI model for WBC recognition generated by supervised training. The subjects of the clinical assessment were 51 healthy persons. Thin-layer blood smears were prepared from peripheral blood and subjected to May-Grünwald-Giemsa staining. Results: The only significantly effective technique among the AI models for WBC recognition was data augmentation with rotation. By contrast, the effectiveness of both image distortion and image scaling was poor, and improved accuracy was limited to a specific WBC subcategory. Conclusion: Although data augmentation methods are often used for achieving high accuracy in AI generation with supervised training, we consider that it is necessary to select the optimal data augmentation method for medical AI generation based on the characteristics of medical images.

  • 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.

  • Fast Neighborhood Rendezvous

    Ryota EGUCHI  Naoki KITAMURA  Taisuke IZUMI  

     
    PAPER-Fundamentals of Information Systems

      Pubricized:
    2021/12/17
      Vol:
    E105-D No:3
      Page(s):
    597-610

    In the rendezvous problem, two computing entities (called agents) located at different vertices in a graph have to meet at the same vertex. In this paper, we consider the synchronous neighborhood rendezvous problem, where the agents are initially located at two adjacent vertices. While this problem can be trivially solved in O(Δ) rounds (Δ is the maximum degree of the graph), it is highly challenging to reveal whether that problem can be solved in o(Δ) rounds, even assuming the rich computational capability of agents. The only known result is that the time complexity of O($O(sqrt{n})$) rounds is achievable if the graph is complete and agents are probabilistic, asymmetric, and can use whiteboards placed at vertices. Our main contribution is to clarify the situation (with respect to computational models and graph classes) admitting such a sublinear-time rendezvous algorithm. More precisely, we present two algorithms achieving fast rendezvous additionally assuming bounded minimum degree, unique vertex identifier, accessibility to neighborhood IDs, and randomization. The first algorithm runs within $ ilde{O}(sqrt{nDelta/delta} + n/delta)$ rounds for graphs of the minimum degree larger than $sqrt{n}$, where n is the number of vertices in the graph, and δ is the minimum degree of the graph. The second algorithm assumes that the largest vertex ID is O(n), and achieves $ ilde{O}left( rac{n}{sqrt{delta}} ight)$-round time complexity without using whiteboards. These algorithms attain o(Δ)-round complexity in the case of $delta = {omega}(sqrt{n} log n)$ and δ=ω(n2/3log4/3n) respectively. We also prove that four unconventional assumptions of our algorithm, bounded minimum degree, accessibility to neighborhood IDs, initial distance one, and randomization are all inherently necessary for attaining fast rendezvous. That is, one can obtain the Ω(n)-round lower bound if either one of them is removed.

  • A Modified Whale Optimization Algorithm for Pattern Synthesis of Linear Antenna Array

    Wentao FENG  Dexiu HU  

     
    LETTER-Numerical Analysis and Optimization

      Pubricized:
    2020/11/09
      Vol:
    E104-A No:5
      Page(s):
    818-822

    A modified whale optimization algorithm (MWOA) with dynamic leader selection mechanism and novel population updating procedure is introduced for pattern synthesis of linear antenna array. The current best solution is dynamic changed for each whale agent to overcome premature with local optima in iteration. A hybrid crossover operator is embedded in original algorithm to improve the convergence accuracy of solution. Moreover, the flow of population updating is optimized to balance the exploitation and exploration ability. The modified algorithm is tested on a 28 elements uniform linear antenna array to reduce its side lobe lever and null depth lever. The simulation results show that MWOA algorithm can improve the performance of WOA obviously compared with other algorithms.

  • Different Antenna Interleaved Allocation with Full and Divided WHT/DFT Spreading for HTRCI-MIMO/OFDM

    Yuta IDA  Takahiro MATSUMOTO  Shinya MATSUFUJI  

     
    PAPER-Wireless Communication Technologies

      Pubricized:
    2020/06/08
      Vol:
    E103-B No:12
      Page(s):
    1438-1446

    The spreading technique can improve system performance since it mitigates the influence of deeply faded subcarrier channels. Proposals for implementing orthogonal frequency division multiplexing (OFDM) systems include frequency symbol spreading (FSS) based on the Walsh-Hadamard transform (WHT) and the discrete Fourier transform (DFT). In a single carrier frequency division multiplexing (SC-FDMA), good performance is obtained by the interleaved subcarrier allocation. Moreover, in a multiple-input multiple-output (MIMO), interleaving the operation of the different transmit antennas is also effective. By combining these techniques, in this paper, we propose the different antenna interleaved allocation with the full and divided WHT/DFT spreading for a high time resolution carrier interferometry (HTRCI) MIMO-OFDM.

  • White-Box Implementation of the Identity-Based Signature Scheme in the IEEE P1363 Standard for Public Key Cryptography

    Yudi ZHANG  Debiao HE  Xinyi HUANG  Ding WANG  Kim-Kwang Raymond CHOO  Jing WANG  

     
    INVITED PAPER

      Pubricized:
    2019/09/27
      Vol:
    E103-D No:2
      Page(s):
    188-195

    Unlike black-box cryptography, an adversary in a white-box security model has full access to the implementation of the cryptographic algorithm. Thus, white-box implementation of cryptographic algorithms is more practical. Nevertheless, in recent years, there is no white-box implementation for public key cryptography. In this paper, we propose the first white-box implementation of the identity-based signature scheme in the IEEE P1363 standard. Our main idea is to hide the private key to multiple lookup tables, so that the private key cannot be leaked during the algorithm executed in the untrusted environment. We prove its security in both black-box and white-box models. We also evaluate the performance of our white-box implementations, in order to demonstrate utility for real-world applications.

  • Using Deep CNN with Data Permutation Scheme for Classification of Alzheimer's Disease in Structural Magnetic Resonance Imaging (sMRI)

    Bumshik LEE  Waqas ELLAHI  Jae Young CHOI  

     
    PAPER-Biological Engineering

      Pubricized:
    2019/04/17
      Vol:
    E102-D No:7
      Page(s):
    1384-1395

    In this paper, we propose a novel framework for structural magnetic resonance image (sMRI) classification of Alzheimer's disease (AD) with data combination, outlier removal, and entropy-based data selection using AlexNet. In order to overcome problems of conventional classical machine learning methods, the AlexNet classifier, with a deep learning architecture, was employed for training and classification. A data permutation scheme including slice integration, outlier removal, and entropy-based sMRI slice selection is proposed to utilize the benefits of AlexNet. Experimental results show that the proposed framework can effectively utilize the AlexNet with the proposed data permutation scheme by significantly improving overall classification accuracies for AD classification. The proposed method achieves 95.35% and 98.74% classification accuracies on the OASIS and ADNI datasets, respectively, for the binary classification of AD and Normal Control (NC), and also achieves 98.06% accuracy for the ternary classification of AD, NC, and Mild Cognitive Impairment (MCI) on the ADNI dataset. The proposed method can attain significantly improved accuracy of up to 18.15%, compared to previously developed methods.

  • Modification of Velvet Noise for Speech Waveform Generation by Using Vocoder-Based Speech Synthesizer Open Access

    Masanori MORISE  

     
    LETTER-Speech and Hearing

      Pubricized:
    2018/12/05
      Vol:
    E102-D No:3
      Page(s):
    663-665

    This paper introduces a new noise generation algorithm for vocoder-based speech waveform generation. White noise is generally used for generating an aperiodic component. Since short-term white noise includes a zero-frequency component (ZFC) and inaudible components below 20 Hz, they are reduced in advance when synthesizing. We propose a new noise generation algorithm based on that for velvet noise to overcome the problem. The objective evaluation demonstrated that the proposed algorithm can reduce the unwanted components.

  • A Property of a Class of Gaussian Periods and Its Application

    Yuhua SUN  Qiang WANG  Qiuyan WANG  Tongjiang YAN  

     
    PAPER-Communication Theory and Signals

      Vol:
    E101-A No:12
      Page(s):
    2344-2351

    In the past two decades, many generalized cyclotomic sequences have been constructed and they have been used in cryptography and communication systems for their high linear complexity and low autocorrelation. But there are a few of papers focusing on the 2-adic complexities of such sequences. In this paper, we first give a property of a class of Gaussian periods based on Whiteman's generalized cyclotomic classes of order 4. Then, as an application of this property, we study the 2-adic complexity of a class of Whiteman's generalized cyclotomic sequences constructed from two distinct primes p and q. We prove that the 2-adic complexity of this class of sequences of period pq is lower bounded by pq-p-q-1. This lower bound is at least greater than one half of its period and thus it shows that this class of sequences can resist against the rational approximation algorithm (RAA) attack.

  • Design and Analysis of First-Order Steerable Nonorthogonal Differential Microphone Arrays

    Qiang YU  Xiaoguang WU  Yaping BAO  

     
    LETTER-Engineering Acoustics

      Vol:
    E101-A No:10
      Page(s):
    1687-1692

    Differential microphone arrays have been widely used in hands-free communication systems because of their frequency-invariant beampatterns, high directivity factors and small apertures. Considering the position of acoustic source always moving within a certain range in real application, this letter proposes an approach to construct the steerable first-order differential beampattern by using four omnidirectional microphones arranged in a non-orthogonal circular geometry. The theoretical analysis and simulation results show beampattern constructed via this method achieves the same direction factor (DF) as traditional DMAs and higher white noise gain (WNG) within a certain angular range. The simulation results also show the proposed method applies to processing speech signal. In experiments, we show the effectiveness and small computation amount of the proposed method.

  • Experimental Tests of a Prototype of IMU-Based Closed-Loop Fuzzy Control System for Mobile FES Cycling with Pedaling Wheelchair

    Takashi WATANABE  Takumi TADANO  

     
    PAPER-Rehabilitation Engineering and Assistive Technology

      Pubricized:
    2018/03/30
      Vol:
    E101-D No:7
      Page(s):
    1906-1914

    Rehabilitation training with pedaling wheelchair in combination with functional electrical stimulation (FES) can be effective for decreasing the risk of falling significantly. Automatic adjustment of cycling speed and making a turn without standstill has been desired for practical applications of the training with mobile FES cycling. This study aimed at developing closed-loop control system of cycling speed with the pedaling wheelchair. Considering clinical practical use with no requirement of extensive modifications of the wheelchair, measurement method of cycling speed with inertial motion measurement units (IMUs) was introduced, and fuzzy controller for adjusting stimulation intensity to regulate cycling speed was designed. The developed prototype of closed-loop FES control system achieved appropriately cycling speed for the different target speeds in most of control trials with neurologically intact subjects. In addition, all the control trials of low speed cycling including U-turn achieved maintaining the target speed without standstill. Cycling distance and cycling time increased with the closed-loop control of low cycling speed compensating decreasing of cycling speed caused by muscle fatigue. From these results, the developed closed-loop fuzzy FES control system was suggested to work reliably in mobile FES cycling.

  • BER Performance of SS System Using a Huffman Sequence against CW Jamming

    Takahiro MATSUMOTO  Hideyuki TORII  Yuta IDA  Shinya MATSUFUJI  

     
    PAPER

      Vol:
    E101-A No:1
      Page(s):
    167-175

    In this paper, we theoretically analyse the influence of intersymbol interference (ISI) and continuous wave interference (CWI) on the bit error rate (BER) performance of the spread spectrum (SS) system using a real-valued Huffman sequence under the additive white Gaussian noise (AWGN) environment. The aperiodic correlation function of the Huffman sequence has zero sidelobes except the shift-end values at the left and right ends of shift. The system can give the unified communication and ranging system because the output of a matched filter (MF) is the ideal impulse by generating transmitted signal of the bit duration T=NTc, N=2n, n=1,2,… from the sequence of length M=2kN+1, k=0,1,…, where Tc is the chip duration and N is the spreading factor. As a result, the BER performance of the system is improved with decrease in the absolute value of the shift-end value, and is not influenced by ISI if the shift-end value is almost zero-value. In addition, the BER performance of the system of the bit duration T=NTc with CWI is improved with increase in the sequence length M=2kN+1, and the system can decrease the influence of CWI.

  • A White-Box Cryptographic Implementation for Protecting against Power Analysis

    Seungkwang LEE  

     
    LETTER-Information Network

      Pubricized:
    2017/10/19
      Vol:
    E101-D No:1
      Page(s):
    249-252

    Encoded lookup tables used in white-box cryptography are known to be vulnerable to power analysis due to the imbalanced encoding. This means that the countermeasures against white-box attacks can not even defend against gray-box attacks. For this reason, those who want to defend against power analysis through the white-box cryptographic implementation need to find other ways. In this paper, we propose a method to defend power analysis without resolving the problematic encoding problem. Compared with the existing white-box cryptography techniques, the proposed method has twice the size of the lookup table and nearly the same amount of computation.

  • Improved Sphere Bound on the MLD Performance of Binary Linear Block Codes via Voronoi Region

    Jia LIU  Meilin HE  Jun CHENG  

     
    PAPER-Coding Theory and Techniques

      Vol:
    E100-A No:12
      Page(s):
    2572-2577

    In this paper, the Voronoi region of the transmitted codeword is employed to improve the sphere bound on the maximum-likelihood decoding (MLD) performance of binary linear block codes over additive white Gaussian noise (AWGN) channels. We obtain the improved sphere bounds both on the frame-error probability and the bit-error probability. With the framework of the sphere bound proposed by Kasami et al., we derive the conditional decoding error probability on the spheres by defining a subset of the Voronoi region of the transmitted codeword, since the Voronoi regions of a binary linear block code govern the decoding error probability analysis over AWGN channels. The proposed bound improves the sphere bound by Kasami et al. and the sphere bound by Herzberg and Poltyrev. The computational complexity of the proposed bound is similar to that of the sphere bound by Kasami et al.

  • A Minimalist's Reversible While Language

    Robert GLÜCK  Tetsuo YOKOYAMA  

     
    PAPER-Software System

      Pubricized:
    2017/02/06
      Vol:
    E100-D No:5
      Page(s):
    1026-1034

    The paper presents a small reversible language R-CORE, a structured imperative programming language with symbolic tree-structured data (S-expressions). The language is reduced to the core of a reversible language, with a single command for reversibly updating the store, a single reversible control-flow operator, a limited number of variables, and data with a single atom and a single constructor. Despite its extreme simplicity, the language is reversibly universal, which means that it is as powerful as any reversible language can be, while it is linear-time self-interpretable, and it allows reversible programming with dynamic data structures. The four-line program inverter for R-CORE is among the shortest existing program inverters, which demonstrates the conciseness of the language. The translator to R-CORE, which is used to show the formal properties of the language, is clean and modular, and it may serve as a model for related reversible translation problems. The goal is to provide a language that is sufficiently concise for theoretical investigations. Owing to its simplicity, the language may also be used for educational purposes.

  • Driver Behavior Assessment in Case of Critical Driving Situations

    Oussama DERBEL  René LANDRY, Jr.  

     
    PAPER

      Vol:
    E100-A No:2
      Page(s):
    491-498

    Driver behavior assessment is a hard task since it involves distinctive interconnected factors of different types. Especially in case of insurance applications, a trade-off between application cost and data accuracy remains a challenge. Data uncertainty and noises make smart-phone or low-cost sensor platforms unreliable. In order to deal with such problems, this paper proposes the combination between the Belief and Fuzzy theories with a two-level fusion based architecture. It enables the propagation of information errors from the lower to the higher level of fusion using the belief and/or the plausibility functions at the decision step. The new developed risk models of the Driver and Environment are based on the accident statistics analysis regarding each significant driving risk parameter. The developed Vehicle risk models are based on the longitudinal and lateral accelerations (G-G diagram) and the velocity to qualify the driving behavior in case of critical events (e.g. Zig-Zag scenario). In case of over-speed and/or accident scenario, the risk is evaluated using our new developed Fuzzy Inference System model based on the Equivalent Energy Speed (EES). The proposed approach and risk models are illustrated by two examples of driving scenarios using the CarSim vehicle simulator. Results have shown the validity of the developed risk models and the coherence with the a-priori risk assessment.

1-20hit(129hit)