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7961-7980hit(21534hit)

  • Anomaly Detection in Electronic Shelf Label Systems

    Yulia PONOMARCHUK  Dae-Wha SEO  

     
    LETTER-Network

      Vol:
    E94-B No:1
      Page(s):
    315-318

    This paper proposes a lightweight, fast and efficient method for the detection of jamming attacks, interference, and other anomalies in electronic shelf label (ESL) systems and wireless sensor networks (WSNs) with periodic data transmission. The proposed method is based on the thresholding technique, which is applied to selected parameters of traffic and allows discrimination of random failures from anomalies and intrusions. It does not require the installation of additional hardware and does not create extra communication costs; its computational requirements are negligible, since it is based on statistical methods. Herein recommendations are provided for choosing a thresholds type. Extensive simulations, made by Castalia simulator for WSNs, show that the proposed method has superior accuracy compared to existing algorithms.

  • Autonomous Community Construction and Reconstruction Technology for Emergency Management

    Fan WEI  Xiaodong LU  Kinji MORI  

     
    PAPER-Community

      Vol:
    E94-B No:1
      Page(s):
    10-17

    Wireless Sensor Network(WSN) is widely used in Emergency Management System(EMS) to assure high safety. Real-timely transmitting emergency information in dynamically changing environment should be assured in mission critical district. Conventional methods based on static situations and centralized approaches can not satisfy this requirement. In this paper, to assure real-time property, autonomous community construction technology is proposed to set special area called community which includes a special passage composed of several routers for emergency information's transmission and routers around this passage in one hop range. Emergency information's transmission is protected by routers around this passage from interference of other sensing information's transmission in and outside community. Moreover, autonomous community reconstruction technology is proposed to guarantee real-time property at failure conditions. In this technology, community members autonomously cooperate and coordinate with each other to setup a bypass in community for transmitting emergency information if fault happens. Evaluation results indicate effectiveness of proposed technology.

  • A Hierarchical Geographical Routing with Alternative Paths Using Autonomous Clustering for Mobile Ad Hoc Networks

    Hiroshi NAKAGAWA  Satoshi TESHIMA  Tomoyuki OHTA  Yoshiaki KAKUDA  

     
    PAPER-Assurance

      Vol:
    E94-B No:1
      Page(s):
    37-44

    Recently in ad hoc networks, routing schemes using location information which is provided by GPS (Global Position System) have been proposed. However, many routing schemes using location information assume that a source node has already known the location information of the destination node and they do not adapt to large ad hoc networks. On another front, the autonomous clustering scheme has been proposed to construct the hierarchical structure in ad hoc networks and adapt to large ad hoc networks. However, even when the hierarchical structure is introduced, there is some problem. The data delivery ratio becomes lower as the node speed becomes higher, and clusterheads have much overhead in the hierarchical routing scheme based on the autonomous clustering scheme. In order to cope with these problems, this paper proposes a new Hierarchical Geographical Routing with Alternative Paths (Hi-GRAP) using the autonomous clustering scheme and shows the effectiveness of the proposed hierarchical geographical routing in comparison with GPSR, Hi-AODV and AODV through simulation experiments with respect to the amount of control packets and the data delivery ratio.

  • On Generalized Cyclotomic Sequence of Order d and Period pq

    Zheng YANG  Pinhui KE  

     
    LETTER-Cryptography and Information Security

      Vol:
    E94-A No:1
      Page(s):
    443-447

    In this letter, we generalize the binary sequence introduced by Li et al. in [S. Q. Li et al., On the randomness generalized cyclotomic sequences of order two and length pq, IEICE Trans. Fund, vol. E90-A, no.9, pp.2037-2041, 2007] to sequence over arbitrary prime fields. Furthermore, the auto-correlation distribution and linear complexity of the proposed sequence are presented.

  • Efficient and Secure Authenticated Key Exchange Protocols in the eCK Model

    Jooyoung LEE  Je Hong PARK  

     
    PAPER-Secure Protocol

      Vol:
    E94-A No:1
      Page(s):
    129-138

    In this paper, we propose two authenticated key exchange(AKE) protocols and prove their security in the extended Canetti-Krawczyk model. The first protocol, called NAXOS+, is obtained by slightly modifying the NAXOS protocol proposed by LaMacchia, Lauter and Mityagin [15]. We prove its security under the Computational Diffie-Hellman (CDH) assumption by using the trapdoor test introduced in [6]. To the authors' knowledge, this is the first AKE protocol which is secure under the CDH assumption in the eCK model. The second protocol, called NETS, enjoys a simple and tight security reduction compared to existing schemes including HMQV and CMQV without using the Forking Lemma. Since each session of the NETS protocol requires only three exponentiations per party, its efficiency is also comparable to MQV, HMQV and CMQV.

  • A Domain Partition Model Approach to the Online Fault Recovery of FPGA-Based Reconfigurable Systems

    Lihong SHANG  Mi ZHOU  Yu HU  Erfu YANG  

     
    PAPER-Nonlinear Problems

      Vol:
    E94-A No:1
      Page(s):
    290-299

    Field programmable gate arrays (FPGAs) are widely used in reliability-critical systems due to their reconfiguration ability. However, with the shrinking device feature size and increasing die area, nowadays FPGAs can be deeply affected by the errors induced by electromigration and radiation. To improve the reliability of FPGA-based reconfigurable systems, a permanent fault recovery approach using a domain partition model is proposed in this paper. In the proposed approach, the fault-tolerant FPGA recovery from faults is realized by reloading a proper configuration from a pool of multiple alternative configurations with overlaps. The overlaps are presented as a set of vectors in the domain partition model. To enhance the reliability, a technical procedure is also presented in which the set of vectors are heuristically filtered so that the corresponding small overlaps can be merged into big ones. Experimental results are provided to demonstrate the effectiveness of the proposed approach through applying it to several benchmark circuits. Compared with previous approaches, the proposed approach increased MTTF by up to 18.87%.

  • Autonomous Decentralized Community Wireless Sensor Network Architecture to Achieve Timely Connection for Online Expansion

    Md. Emdadul HAQUE  Shoichi MURAKAMI  Xiaodong LU  Kinji MORI  

     
    PAPER-Community

      Vol:
    E94-B No:1
      Page(s):
    2-9

    Wireless sensor networks represent a new data collection paradigm in which expandability plays an important role. In a practical monitoring environment, for example, food factory monitoring system, sensor relocations and reorganizations are necessary with reorganization of production lines and starting of new production lines. These relocations sometime make congestion in some area of the network. In this dynamic changing environment online expansion is a challenging problem for resource constraint network. This paper proposes a two-tier autonomous decentralized community architecture for wireless sensor network to solve the problem. The first layer consists of sensors and second layer consists of routers. In the architecture routers make community (a group of nodes mutually cooperate for a common goal is a community). The goal of this paper is to introduce the concept of sharing information among routers of the community to decrease sensor connection time for the network especially for the dynamic changing environment. Results show that our proposed technologies can reduce sensor connection time to achieve online expansion.

  • Mobile Terminal Substitution of Vehicular Collision Avoidance Support System (VCASS) for Non-VCASS Vehicles: S-VCASS

    Tomotaka WADA  Shinji NAKAI  Tetsuya MARUOKA  Haokun WANG  Hiromi OKADA  

     
    PAPER-Intelligent Transport System

      Vol:
    E94-A No:1
      Page(s):
    410-419

    In this paper, we develop a VCASS substitution system (S-VCASS) using a personal mobile terminal in order to improve the effectiveness of VCASS in an environment comprising both VCASS and non-VCASS vehicles. We propose three new pedestrian state judgment algorithms that can be implemented on a personal mobile terminal for inter-vehicle communications. We evaluate the performances of the three proposed algorithms with real vehicles. Finally, we show that the proposed algorithms can recognize vehicles without VCASS.

  • Cyclic Vector Multiplication Algorithm and Existence Probability of Gauss Period Normal Basis

    Kenta NEKADO  Yasuyuki NOGAMI  Hidehiro KATO  Yoshitaka MORIKAWA  

     
    PAPER-Mathematics

      Vol:
    E94-A No:1
      Page(s):
    172-179

    Recently, pairing-based cryptographic application sch-emes have attracted much attentions. In order to make the schemes more efficient, not only pairing algorithm but also arithmetic operations in extension field need to be efficient. For this purpose, the authors have proposed a series of cyclic vector multiplication algorithms (CVMAs) corresponding to the adopted bases such as type-I optimal normal basis (ONB). Note here that every basis adapted for the conventional CVMAs are just special classes of Gauss period normal bases (GNBs). In general, GNB is characterized with a certain positive integer h in addition to characteristic p and extension degree m, namely type-⟨h.m⟩ GNB in extension field Fpm. The parameter h needs to satisfy some conditions and such a positive integer h infinitely exists. From the viewpoint of the calculation cost of CVMA, it is preferred to be small. Thus, the minimal one denoted by hmin will be adapted. This paper focuses on two remaining problems: 1) CVMA has not been expanded for general GNBs yet and 2) the minimal hmin sometimes becomes large and it causes an inefficient case. First, this paper expands CVMA for general GNBs. It will improve some critical cases with large hmin reported in the conventional works. After that, this paper shows a theorem that, for a fixed prime number r, other prime numbers modulo r uniformly distribute between 1 to r-1. Then, based on this theorem, the existence probability of type-⟨hmin,m⟩ GNB in Fpm and also the expected value of hmin are explicitly given.

  • Toward Digital Watermarking for Cryptographic Data

    Maki YOSHIDA  Toru FUJIWARA  

     
    LETTER

      Vol:
    E94-A No:1
      Page(s):
    270-272

    This paper introduces a novel type of digital watermarking, which is mainly designed for embededing information into cryptographic data such as keys, ciphertexts, and signatures. We focus on a mathematical structure of the recent major cryptosystems called pairing-based schemes. We present a detection-type watermarking scheme by which a watermark is visible by anyone but unremovable without secret trapdoor. The important feature is that both correctness and security of cryptographic data remain satisfied even if the trapdoor is published.

  • Propagation Analysis of Electromagnetic Waves in 700 MHz Band at Intersection for Inter-Vehicle Communications Using the FDTD Method

    Kenji TAGUCHI  Tatsuya KASHIWA  Kohzoh OHSHIMA  Takeshi KAWAMURA  

     
    PAPER-Radiation and Propagation

      Vol:
    E94-C No:1
      Page(s):
    18-23

    Inter-vehicle communication (IVC) system using 700 MHz band to prevent car crashes has been proposed recently. In this paper, we first apply the FDTD method to the analyses of propagation characteristics at an intersection for IVC. We investigate the propagation characteristics considering the electrical conductivities, thickness and windows of building wall and pedestrians. As a result, it is shown that the electrical conductivities and thickness of building wall have a slight influence. In contrast, windows and pedestrians have a great influence on the propagation characteristics. Furthermore, the azimuth delay profiles are obtained by using the MUSIC algorithm.

  • Scalable Backup Configurations Creation for IP Fast Reroute

    Shohei KAMAMURA  Takashi MIYAMURA  Yoshihiko UEMATSU  Kohei SHIOMOTO  

     
    PAPER-Internet

      Vol:
    E94-B No:1
      Page(s):
    109-117

    IP Fast Reroute techniques have been proposed to achieve fast failure recovery, just a few milliseconds. The basic idea of IP Fast Reroute is to reduce recovery time by precomputing backup routes. The multiple routing configurations (MRC) algorithm was proposed to implement IP Fast Reroute. MRC prepares backup configurations, which are used for finding a detour route after a failure. However, this algorithm establishes too many backup configurations to recover from failures. We propose a new backup configuration computation algorithm that creates the fewest possible configurations. The basic idea is to construct a spanning tree that excludes failure links in each backup configuration. We show that the effectiveness of our algorithm is especially high in large-scale power-law networks.

  • A Reference Programming Model for Building Context-Aware Application

    Junbin ZHANG  Yong QI  Di HOU  Ming LI  

     
    PAPER-Information Network

      Vol:
    E94-D No:1
      Page(s):
    114-126

    Context-aware applications are a key aspect of pervasive computing. The core issue of context-aware application development is how to make the application behave suitably according to the changing context without coupling such context dependencies in the program. Several programming paradigms and languages have been proposed to facilitate the development, but they are either lack of sufficient flexibility or somewhat complex for programming and deploying. A reference programming model is proposed in this paper to make up inadequacy of those approaches. In the model, virtual tables constructed by system and maintained by space manager connect knowledge of both developer and space manager while separating dependency between context and application logic from base program. Hierarchy and architecture of the model are presented, and implementation suggestions are also discussed. Validation and evaluation show that the programming model is lightweight and easy to be implemented and deployed. Moreover, the model brings better flexibility for developing context-aware applications.

  • Analysis Method of Ground Wave Propagation over Land-to-Sea Mixed-Path by Using Helmholtz-Kirchhoff Integral Theorem

    Toru KAWANO  Keiji GOTO  Toyohiko ISHIHARA  

     
    PAPER-Radiation and Propagation

      Vol:
    E94-C No:1
      Page(s):
    10-17

    In this paper, we have derived a novel integral representation for the ground wave propagation over land-to-sea mixed-paths by applying the Helmholtz-Kirchhoff integral theorem. By using the method of stationary phase applicable uniformly as the stationary phase point approaches the endpoint of the integral, we have derived the asymptotic solution for the scattered fields consisting of the first-order and the second-order diffraction terms. We show that the asymptotic solution thus derived agrees with the asymptotic solution derived by applying the aperture field method (AFM) and the method of stationary phase. We have confirmed the validity and the utility of the novel integral representation and its asymptotic solution by comparing with the widely used mixed-path theorem and the experimental measurement performed in Kanto area and Tokyo bay.

  • Improving the Performance of the Hough Detector in Search Radars

    Ali MOQISEH  Mahdi HADAVI  Mohammad M. NAYEBI  

     
    PAPER-Sensing

      Vol:
    E94-B No:1
      Page(s):
    273-281

    In this paper, the inherent problem of the Hough transform when applied to search radars is considered. This problem makes the detection probability of a target depend on the length of the target line in the data space in addition to the received SNR from it. It is shown that this problem results in a non-uniform distribution of noise power in the parameter space. In other words, noise power in some regions of the parameter space is greater than in others. Therefore, the detection probability of the targets covered by these regions will decrease. Our solution is to modify the Hough detector to remove the problem. This modification uses non-uniform quantization in the parameter space based on the Maximum Entropy Quantization method. The details of implementing the modified Hough detector in a search radar are presented according to this quantization method. Then, it is shown that by using this method the detection performance of the target will not depend on its length in the data space. The performance of the modified Hough detector is also compared with the standard Hough detector by considering their probability of detection and probability of false alarm. This comparison shows the performance improvement of the modified detector.

  • A Center-Feed Linear Array of Reflection-Canceling Slot Pairs on Post-Wall Waveguide

    Jae-Ho LEE  Jiro HIROKAWA  Makoto ANDO  

     
    LETTER-Antennas and Propagation

      Vol:
    E94-B No:1
      Page(s):
    326-329

    Post-wall waveguide with a linear array of reflection-canceling slot pairs and center-feed is designed to cancel the frequency dependent tilting of the main beam and enhance the bandwidth of the antenna boresight gain. The array is fed at the center of the waveguide from the backside; the length of the radiating waveguide is halved and the long line effect in traveling wave operation is suppressed. Authors establish the array design procedure in separate steps to reduce the computational load in the iterative optimization by using Ansoft HFSS simulator. A center-feed linear array as well as an end-feed equivalent with uniform excitation is designed for 25.6 GHz operation and measured. The measured performances confirm the design and the advantage of the centre-feed; a frequency independent boresight beam is observed and the frequency bandwidth for 3 dB gain reduction is enhanced by 1.5 times compared to the end-feed array.

  • Performance Analysis of Persistent Scheduling for VoIP Services in Mobile WiMAX Systems

    Jaewoo SO  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E94-B No:1
      Page(s):
    175-182

    Broadcasting information to users about new resource assignments generates a substantial mapping overhead. The mapping overhead influences the system throughput and, in particular, seriously affects the performance of voice-over-Internet protocol (VoIP) services. Persistent scheduling was introduced to reduce the mapping overhead. However, up to now no studies have mathematically analyzed the performance of the persistent scheduling. This paper develops analytical and simulation models and evaluates the performance of the persistent scheduling for VoIP services in mobile WiMAX systems.

  • F-Scan: A DFT Method for Functional Scan at RTL

    Marie Engelene J. OBIEN  Satoshi OHTAKE  Hideo FUJIWARA  

     
    PAPER-Information Network

      Vol:
    E94-D No:1
      Page(s):
    104-113

    Due to the difficulty of test pattern generation for sequential circuits, several design-for-testability (DFT) approaches have been proposed. An improvement to these current approaches is needed to cater to the requirements of today's more complicated chips. This paper introduces a new DFT method applicable to high-level description of circuits, which optimally utilizes existing functional elements and paths for test. This technique, called F-scan, effectively reduces the hardware overhead due to test without compromising fault coverage. Test application time is also kept at the minimum. The comparison of F-scan with the performance of gate-level full scan design is shown through the experimental results.

  • Security of Cryptosystems Using Merkle-Damgård in the Random Oracle Model

    Yusuke NAITO  Kazuki YONEYAMA  Lei WANG  Kazuo OHTA  

     
    PAPER-Public Key Cryptography

      Vol:
    E94-A No:1
      Page(s):
    57-70

    Since the Merkle-Damgård hash function (denoted by MDFH) that uses a fixed input length random oracle as a compression function is not indifferentiable from a random oracle (denoted by RO) due to the extension attack, there is no guarantee for the security of cryptosystems, which are secure in the RO model, when RO is instantiated with MDHF. This fact motivates us to establish a criteria methodology for confirming cryptosystems security when RO is instantiated with MDHF. In this paper, we confirm cryptosystems security by using the following approach: 1.Find a weakened random oracle (denoted by WRO) which leaks values needed to realize the extension attack. 2.Prove that MDHF is indifferentiable from WRO. 3.Prove cryptosystems security in the WRO model. The indifferentiability framework of Maurer, Renner and Holenstein guarantees that we can securely use the cryptosystem when WRO is instantiated with MDHF. Thus we concentrate on such finding WRO. We propose Traceable Random Oracle (denoted by TRO) which leaks values enough to permit the extension attack. By using TRO, we can easily confirm the security of OAEP encryption scheme and variants of OAEP encryption scheme. However, there are several practical cryptosystems whose security cannot be confirmed by TRO (e.g. RSA-KEM). This is because TRO leaks values that are irrelevant to the extension attack. Therefore, we propose another WRO, Extension Attack Simulatable Random Oracle (denoted by ERO), which leaks just the value needed for the extension attack. Fortunately, ERO is necessary and sufficient to confirm the security of cryptosystems under MDHF. This means that the security of any cryptosystem under MDHF is equivalent to that under the ERO model. We prove that RSA-KEM is secure in the ERO model.

  • A Low-Power Mixed-Architecture ADC with Time-Interleaved Correlated Double Sampling Technique and Power-Efficient Back-End Stages

    Jin-Fu LIN  Soon-Jyh CHANG  

     
    PAPER-Electronic Circuits

      Vol:
    E94-C No:1
      Page(s):
    89-101

    In this paper, two techniques for implementing a low-power pipelined analog-to-digital converter (ADC) are proposed. First, the time-interleaved correlated double sampling (CDS) technique is proposed to compensate the finite gain error of operational amplifiers in switched-capacitor circuits without a half-rate front-end sample-and-hold amplifier (SHA). Therefore, low-gain amplifiers and the SHA-less architecture can be used to effectively reduce power consumption of a pipelined ADC. Second, the back-end pipelined stages of a pipelined ADC are implemented using a low-power time-interleaved successive approximation (SA) ADC rather than operational amplifiers to further reduce the power consumption of the proposed pipelined ADC. A 9-bit, 100-MS/s hybrid pipelined-SA ADC is implemented in the TSMC 0.13 µm triple-well 1P8M CMOS process. The ADC achieves a spurious free dynamic range (SFDR) of 62.15 dB and a signal-to-noise distortion ratio (SNDR) of 50.85-dB for 2-MHz input frequency at a 100-MS/s sampling rate. The power consumption is 21.2 mW from a 1.2 V supply. The core area of the ADC is 1.6 mm2.

7961-7980hit(21534hit)