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[Keyword] CTI(8214hit)

3041-3060hit(8214hit)

  • Reduction Processing of the Position Estimation Error Using Transmitted Directivity Information

    Hiroyuki HATANO  Tomoharu MIZUTANI  Yoshihiko KUWAHARA  

     
    PAPER-ITS

      Vol:
    E95-A No:1
      Page(s):
    286-295

    We consider the position estimation system for targets which exist in near wide area. The system has multiple sensors and estimates the position with multiple receivers. In the past, if receivers were arranged on a straight line, the large position error in the same direction of the line is generated. In order to reduce the error, we propose a novel estimation algorithm using transmitter's directivity information. Our system use directional emission made by an array of antennas in a transmitter. In this paper, the error characteristic which should be solved is introduced firstly. After that, our algorithm is presented. Finally the performance of the error reduction is shown by computer simulations. And we also confirm the reduction by experimental trials. The results indicate good reduction of the error.

  • A Uniform Asymptotic Solution for Reflection and Beam Shift of a Gaussian Beam at a Plane Dielectric Interface

    Dinh Trong QUANG  Keiji GOTO  Toru KAWANO  Toyohiko ISHIHARA  

     
    PAPER-Scattering and Diffraction

      Vol:
    E95-C No:1
      Page(s):
    16-26

    The problem of a Gaussian beam that is incident on a plane dielectric interface from a denser dielectric medium to a rarer one and is reflected at the interface has been important research subjects studied by many researchers. In this paper, we have obtained a novel uniform asymptotic solution for reflection and beam shift of the Gaussian beam that is incident on the interface from the denser medium. The uniform asymptotic solution consists of the geometrically reflected beam, the lateral beam if any, and the newly derived transition beam which plays an important role in the transition region near the critical angle of the total reflection. We have confirmed the validity of the uniform asymptotic solution by comparing with the reference solution obtained numerically from the integral representation. We have shown that, in addition to the Goos-Hanchen shift and the angular shift, the Gaussian beam is shifted to either direction by the interference of the geometrically reflected beam and the lateral beam near the critical angle of the total reflection.

  • Iterative Multi-Track ITI Canceller for Nonbinary-LDPC-Coded Two-Dimensional Magnetic Recording

    Masaaki FUJII  

     
    PAPER-Storage Technology

      Vol:
    E95-C No:1
      Page(s):
    163-171

    An iterative inter-track interference (ITI) cancelling scheme is described for multi-track signal detection in nonbinary (NB)-LDPC-coded two-dimensional magnetic recording. The multi-track iterative ITI canceller that we propose consists of multi-track soft interference cancellers (SICs), two-dimensional partial response (TDPR) filters, noise-predictive max-log-MAP detectors, and an NB-LDPC decoder. TDPR filters using an ITI-suppressing tap-weight vector mitigate ITI in the first iteration. Multi-track SICs and TDPR filters adjusted to the residual two-dimensional ISI signals efficiently detect multi-track signals in the latter iterations. The simulation results demonstrated that our proposed iterative multi-track ITI canceller achieves frame error rates close to those obtained in a non-ITI case in media-noise-dominant environments when the both-side off-track ratio is up to 50%.

  • A Fault-Tolerant Architecture with Error Correcting Code for the Instruction-Level Temporal Redundancy

    Chao YAN  Hongjun DAI  Tianzhou CHEN  

     
    PAPER-Trust

      Vol:
    E95-D No:1
      Page(s):
    38-45

    Soft error has become an increasingly significant concern in modern micro-processor design, it is reported that the instruction-level temporal redundancy in out-of-order cores suffers an performance degradation up to 45%. In this work, we propose a fault tolerant architecture with fast error correcting codes (such as the two-dimensional code) based on double execution. Experimental results show that our scheme can gain back IPC loss between 9.1% and 10.2%, with an average around 9.2% compared with the conventional double execution architecture.

  • A Fast Sub-Volume Search Method for Human Action Detection

    Ping GUO  Zhenjiang MIAO  Xiao-Ping ZHANG  Zhe WANG  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E95-D No:1
      Page(s):
    285-288

    This paper discusses the task of human action detection. It requires not only classifying what type the action of interest is, but also finding actions' spatial-temporal locations in a video. The novelty of this paper lies on two significant aspects. One is to introduce a new graph based representation for the search space in a video. The other is to propose a novel sub-volume search method by Minimum Cycle detection. The proposed method has a low computation complexity while maintaining a high action detection accuracy. It is evaluated on two challenging datasets which are captured in cluttered backgrounds. The proposed approach outperforms other state-of-the-art methods in most situations in terms of both Precision-Recall values and running speeds.

  • Security of Sequential Multiple Encryption

    Atsushi FUJIOKA  Yoshiaki OKAMOTO  Taiichi SAITO  

     
    PAPER-Public Key Cryptography

      Vol:
    E95-A No:1
      Page(s):
    57-69

    This paper analyzes security of sequential multiple encryptions based on asymmetric key encryptions, and shows that a sequential construction of secure multiple encryptions exists. The sequential multiple encryption scheme can be proved to be indistinguishable against chosen ciphertext attacks for multiple encryptions (IND-ME-CCA), where the adversary can access to the decryption oracle of the multiple encryption, even when all the underlying encryptions of the multiple encryption are indistinguishable against chosen plaintext attacks (IND-CPA). We provide an extended security notion of sequential multiple encryptions, in which the adversary is allowed to access decryption oracles of the underlying encryptions in addition to the multiple encryption, and show that our constructed scheme satisfies the security notion when all the underlying encryptions are indistinguishable against chosen ciphertext attacks (IND-CCA).

  • Preimage and Second-Preimage Attacks on PGV Hashing Modes of Round-Reduced ARIA, Camellia, and Serpent

    Deukjo HONG  Bonwook KOO  Dong-Chan KIM  

     
    PAPER-Cryptography and Information Security

      Vol:
    E95-A No:1
      Page(s):
    372-380

    We present pseudo-preimage attacks on Davis-Meyer mode of reduced rounds of the block ciphers ARIA, Camellia, and Serpent by using Sasaki's framework. They yield preimage or second-preimage attacks on PGV hashing modes. We develop proper initial structures for applying meet-in-the-middle techniques to the block ciphers, by considering their diffusion layers, and propose a method to find matching-check equations for indirect partial matching technique with a binary matrix. These works enable us to attack 5 rounds of ARIA, 7 rounds of Camellia, and 4 rounds of Serpent faster than brute force attack.

  • A Configurable On-Chip Glitchy-Clock Generator for Fault Injection Experiments

    Sho ENDO  Takeshi SUGAWARA  Naofumi HOMMA  Takafumi AOKI  Akashi SATOH  

     
    LETTER

      Vol:
    E95-A No:1
      Page(s):
    263-266

    This paper presents a glitchy-clock generator integrated in FPGA for evaluating fault injection attacks and their countermeasures on cryptographic modules. The proposed generator exploits clock management capabilities, which are common in modern FPGAs, to generate clock signal with temporal voltage spike. The shape and timing of the glitchy-clock cycle are configurable at run time. The proposed generator can be embedded in a single FPGA without any external instrument (e.g., a pulse generator and a variable power supply). Such integration enables reliable and reproducible fault injection experiments. In this paper, we examine the characteristics of the proposed generator through experiments on Side-channel Attack Standard Evaluation Board (SASEBO). The result shows that the timing of the glitches can be controlled at the step of about 0.17 ns. We also demonstrate its application to the safe-error attack against an RSA processor.

  • A Multiband Monopole Antenna with Modified Fractal Loop Parasitic for DCS 1800, WLAN, WiMAX and IMT Advanced Systems

    Chatree MAHATTHANAJATUPHAT  Norakamon WONGSIN  Prayoot AKKARAEKTHALIN  

     
    PAPER-Antennas

      Vol:
    E95-B No:1
      Page(s):
    27-33

    A multiband monopole antenna with modified fractal loop parasitic is presented. Especially, bow-tie stubs and a modified fractal loop are attached to the sides and bottom of a strip line monopole antenna, respectively, in order to generate the multi-resonant frequencies for the applications of wireless communication systems. The characteristics of the presented antenna have been examined by using the simulation software. The comparison between the simulated and measured results confirms the good agreement. The results show good multiband operation with 10 dB impedance bandwidths of 15.55%, 8.75%, and 31.94% at the resonant frequencies of 1.8 GHz, 2.4 GHz, and 3.6 GHz, respectively, which cover the operating band applications of DCS 1800, WLAN (IEEE802.11 b/g), WiMAX, and IMT advanced system (4G mobile communication system).

  • High Frequency Ray-Mode Coupling Analysis of Plane Wave Diffraction by a Wide and Thick Slit on a Conducting Screen

    Hiroshi SHIRAI  Ryoichi SATO  

     
    PAPER-Scattering and Diffraction

      Vol:
    E95-C No:1
      Page(s):
    10-15

    Diffraction field by a wide and thick slit on a conducting screen has been analyzed. High frequency ray-mode coupling analysis has been utilized, and the total diffracted or radiated field in each region is considered as a summation of successive modal radiation contribution due to the original modal excitation by the incident plane wave. Our derived results are compared with those obtained by other solutions, and good agreement has been observed, and the validity of our formulation is confirmed.

  • A Class of 1-Resilient Functions in Odd Variables with High Nonlinearity and Suboptimal Algebraic Immunity

    Yusong DU  Fangguo ZHANG  

     
    LETTER-Cryptography and Information Security

      Vol:
    E95-A No:1
      Page(s):
    417-420

    Based on Tu-Deng's conjecture and the Tu-Deng function, in 2010, X. Tang et al. proposed a class of Boolean functions in even variables with optimal algebraic degree, very high nonlinearity and optimal algebraic immunity. In this corresponding, we consider the concatenation of Tang's function and another Boolean function, and study its cryptographic properties. With this idea, we propose a class of 1-resilient Boolean functions in odd variables with optimal algebraic degree, good nonlinearity and suboptimal algebraic immunity based on Tu-Deng's conjecture.

  • Noise Canceling Balun-LNA with Enhanced IIP2 and IIP3 for Digital TV Applications

    Saeed SAEEDI  Mojtaba ATARODI  

     
    PAPER-Integrated Electronics

      Vol:
    E95-C No:1
      Page(s):
    146-154

    An inductorless low noise amplifier (LNA) with active balun for digital TV (DTV) applications is presented. The LNA exploits a noise cancellation technique which allows for simultaneous wide-band impedance matching and low noise design. The matching and amplifier stages in the LNA topology perform single-ended to differential signal conversion with balanced output. The second and third-order nonlinearity of the individual amplifiers as well as the distortion caused by the interaction between the stages are suppressed to achieve high IIP2 and IIP3. A method for intrinsic cancellation of the second-order interaction is employed to reduce the dependence of the IIP3 on the frequency spacing between the interfering signals in the two-tone test of DTV tuners. Fabricated in a 0.18 µm CMOS technology, the LNA core size is 0.21 mm2. Measurements show that the LNA IIP3 and IIP2 are +12 dBm and +21 dBm, respectively. The IIP3 variation is less than 5 dB in the 10 MHz to 200 MHz frequency spacing range. A voltage gain of 14.5 dB and a noise figure below 4 dB are achieved in a frequency range from 100 MHz to 1 GHz. The LNA consumes 11 mA from a 1.8 V supply voltage.

  • Software Protection Combined with Tamper-Proof Device

    Kazuhide FUKUSHIMA  Shinsaku KIYOMOTO  Yutaka MIYAKE  

     
    PAPER-Software Protection

      Vol:
    E95-A No:1
      Page(s):
    213-222

    Establishment of a practical software protection method is a major issue in software distribution. There are several approaches to the issue; however, no practical, secure method for mobile phone applications has been proposed. In this paper, we propose a new software protection scheme combined with a tamper-proof device (TPD) in order to achieve computational security against illegal analysis and copying of the target program. Our scheme achieves a reasonable level of security for encoding the data and variables in a program. The program on a mobile phone deals only with encoded data that is difficult to compromise, and the TPD plays a role of decoding execution results. We implemented the proposed scheme on a 3G mobile phone and a user identification module (UIM). An analysis and copying of the protected program impose exponential computation complexities under our attack model.

  • TE Plane Wave Reflection and Transmission from a Two-Dimensional Random Slab – Slanted Fluctuation –

    Yasuhiko TAMURA  

     
    PAPER-Random Media and Rough Surfaces

      Vol:
    E95-C No:1
      Page(s):
    36-43

    This paper deals with reflection and transmission of a TE plane wave from a two-dimensional random slab with slanted fluctuation by means of the stochastic functional approach. Such slanted fluctuation of the random slab is written by a homogeneous random field having a power spectrum with a rotation angle. By starting with the previous paper [IEICE Trans. Electron., Vol. E92-C, no.1, pp.77–84, January 2009], any statistical quantities are immediately obtained even for slanted fluctuation cases. The first-order incoherent scattering cross section is numerically calculated and illustrated in figures. It is then newly found that shift and separation phenomena of the leading or enhanced peaks at four characteristic scattering angles take place in the transmission and reflection sides, respectively.

  • Design and Fabrication of PTFE-Filled Waveguide Components by SR Direct Etching

    Mitsuyoshi KISHIHARA  Hiroaki IKEUCHI  Yuichi UTSUMI  Tadashi KAWAI  Isao OHTA  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E95-C No:1
      Page(s):
    122-129

    The metallic waveguide is one of many effective media for millimeter- and submillimeter-waves because of the advantage of its low-loss nature. This paper describes the fabrication method of PTFE-filled waveguide components with the use of the SR (synchrotron radiation) direct etching process of PTFE, sputter deposition of metal, and electroplating. PTFE is known as a difficult material to process with high precision. However, it has been reported that PTFE microstructures can be fabricated by the direct exposure to SR. First, an iris-coupled waveguide BPF with 5-stage Chebyshev response is designed and fabricated for the Q-band. It is demonstrated that the present process is applicable for the fabrication of the practical components inclusive of narrow patterns. Then, a cruciform 3 dB coupler with air-filled posts is designed and fabricated for the Q-band. Directivity and matched state of the coupler can be realized by “holes” in the dielectric material. The measurement results are also shown.

  • Collision Resistance of Hash Functions in a Weak Ideal Cipher Model

    Shoichi HIROSE  Hidenori KUWAKADO  

     
    LETTER

      Vol:
    E95-A No:1
      Page(s):
    252-255

    This article discusses the provable security of block-cipher-based hash functions. It introduces a new model called a weak ideal cipher model. In this model, an adversary is allowed to make key-disclosure queries to the oracle as well as encryption and decryption queries. A key-disclosure query is a pair of a plaintext and a ciphertext, and the reply is a corresponding key. Thus, in this model, a block cipher is random but completely insecure as a block cipher. It is shown that collision resistant hash functions can be constructed even in this weak model.

  • Pre-Compensation Clutter Range-Dependence STAP Algorithm for Forward-Looking Airborne Radar Utilizing Knowledge-Aided Subspace Projection

    Teng LONG  Yongxu LIU  Xiaopeng YANG  

     
    PAPER-Radars

      Vol:
    E95-B No:1
      Page(s):
    97-105

    The range-dependence of clutter spectrum for forward-looking airborne radar strongly affects the accuracy of the estimation of clutter covariance matrix at the range under test, which results in poor clutter suppression performance if the conventional space-time adaptive processing (STAP) algorithms were applied, especially in the short range cells. Therefore, a new STAP algorithm with clutter spectrum compensation by utilizing knowledge-aided subspace projection is proposed to suppress clutter for forward-looking airborne radar in this paper. In the proposed method, the clutter covariance matrix of the range under test is firstly constructed based on the prior knowledge of antenna array configuration, and then by decomposing the corresponding space-time covariance matrix to calculate the clutter subspace projection matrix which is applied to transform the secondary range samples so that the compensation of clutter spectrum for forward-looking airborne radar is accomplished. After that the conventional STAP algorithm can be applied to suppress clutter in the range under test. The proposed method is compared with the sample matrix inversion (SMI) and the Doppler Warping (DW) methods. The simulation results show that the proposed STAP method can effectively compensate the clutter spectrum and mitigate the range-dependence significantly.

  • FDTD Analysis of Radio Wave Propagation at Intersection Surrounded by Concrete Block Walls in Residential Area for Inter-Vehicle Communications Using 720 MHz Band

    Kenji TAGUCHI  Suguru IMAI  Tatsuya KASHIWA  Kohzoh OHSHIMA  Takeshi KAWAMURA  

     
    PAPER-Numerical Techniques

      Vol:
    E95-C No:1
      Page(s):
    79-85

    An inter-vehicle communication system for the 720 MHz band that is designed to prevent car crashes at intersections has recently been proposed in Japan. This paper presents an analysis of the propagation characteristics of an intersection surrounded by concrete block walls in a residential area. The propagation characteristics were analyzed for the first time using the finite-difference time-domain (FDTD) method. We investigated the influence of wall thickness and source locations on the propagation characteristics. The results of our investigation showed that the most commonly used wall thickness and source locations do not strongly affect propagation loss. Furthermore, we analyzed the power delay profile and delay spread by taking into consideration the structure of the concrete block walls.

  • Method of Image Green's Function in Grating Theory

    Junichi NAKAYAMA  Yasuhiko TAMURA  

     
    BRIEF PAPER-Periodic Structures

      Vol:
    E95-C No:1
      Page(s):
    93-96

    This paper deals with the diffraction of a transverse magnetic (TM) plane wave by a perfectly conductive periodic surface by an integral method. However, it is known that a conventional integral method does not work for a critical angle of incidence, because of divergence of a periodic Green's function (integral kernel). To overcome such a divergence difficulty, we introduce an image Green's function which is physically defined as a field radiated from an infinite phased array of dipoles. By use of the image Green's function, it is newly shown that the diffracted field is represented as a sum of radiation from the periodic surface and its image surface. Then, this paper obtains a new image integral equation for the basic surface current, which is solved numerically. A numerical result is illustrated for a very rough sinusoidal surface. Then, it is concluded that the method of image Green's function works practically even at a critical angle of incidence.

  • Combinatorial Auction-Based Marketplace Mechanism for Cloud Service Reservation

    Ikki FUJIWARA  Kento AIDA  Isao ONO  

     
    PAPER-Computer System

      Vol:
    E95-D No:1
      Page(s):
    192-204

    This paper proposes a combinatorial auction-based marketplace mechanism for cloud computing services, which allows users to reserve arbitrary combination of services at requested timeslots, prices and quality of service. The proposed mechanism helps enterprise users build workflow applications in a cloud computing environment, specifically on the platform-as-a-service, where the users need to compose multiple types of services at different timeslots. The proposed marketplace mechanism consists of a forward market for an advance reservation and a spot market for immediate allocation of services. Each market employs mixed integer programming to enforce a Pareto optimum allocation with maximized social economic welfare, as well as double-sided auction design to encourage both users and providers to compete for buying and selling the services. The evaluation results show that (1) the proposed forward/combinatorial mechanism outperforms other non-combinatorial and/or non-reservation (spot) mechanisms in both user-centric rationality and global efficiency, and (2) running both a forward market and a spot market improves utilization without disturbing advance reservations depending on the provider's policy.

3041-3060hit(8214hit)