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  • Discriminating Unknown Objects from Known Objects Using Image and Speech Information

    Yuko OZASA  Mikio NAKANO  Yasuo ARIKI  Naoto IWAHASHI  

     
    PAPER-Multimedia Pattern Processing

      Pubricized:
    2014/12/16
      Vol:
    E98-D No:3
      Page(s):
    704-711

    This paper deals with a problem where a robot identifies an object that a human asks it to bring by voice when there is a set of objects that the human and the robot can see. When the robot knows the requested object, it must identify the object and when it does not know the object, it must say it does not. This paper presents a new method for discriminating unknown objects from known objects using object images and human speech. It uses a confidence measure that integrates image recognition confidences and speech recognition confidences based on logistic regression.

  • Split-Jaccard Distance of Hierarchical Decompositions for Software Architecture

    Ki-Seong LEE  Byung-Woo HONG  Youngmin KIM  Jaeyeop AHN  Chan-Gun LEE  

     
    LETTER-Software Engineering

      Pubricized:
    2014/11/20
      Vol:
    E98-D No:3
      Page(s):
    712-716

    Most previous approaches on comparing the results for software architecture recovery are designed to handle only flat decompositions. In this paper, we propose a novel distance called Split-Jaccard Distance of Hierarchical Decompositions. It extends the Jaccard coefficient and incorporates the concept of the splits of leaves in a hierarchical decomposition. We analyze the proposed distance and derive its properties, including the lower-bound and the metric space.

  • Virtual Network Embedding across Multiple Domains with Secure Multi-Party Computation

    Toru MANO  Takeru INOUE  Kimihiro MIZUTANI  Osamu AKASHI  

     
    PAPER-Network

      Vol:
    E98-B No:3
      Page(s):
    437-448

    Network virtualization is one of the promising technologies that can increase flexibility, diversity, and manageability of networks. Building optimal virtual networks across multiple domains is getting much attention, but existing studies were based on an unrealistic assumption, that is, providers' private information can be disclosed; as is well known, providers never actually do that. In this paper, we propose a new method that solves this multi-domain problem without revealing providers' private information. Our method uses an advanced secure computation technique called multi-party computation (MPC). Although MPC enables existing unsecured methods to optimize virtual networks securely, it requires very large time to finish the optimization due to the MPC's complex distributed protocols. Our method, in contrast, is designed to involve only a small number of MPC operations to find the optimal solution, and it allows providers to execute a large part of the optimization process independently without heavy distributed protocols. Evaluation results show that our method is faster than an existing method enhanced with MPC by several orders of magnitude. We also unveil that our method has the same level of embedding cost.

  • Multidimensional QoE Estimation of Multi-View Video and Audio (MVV-A) IP Transmission

    Toshiro NUNOME  Shuji TASAKA  

     
    PAPER-Multimedia Systems for Communications

      Vol:
    E98-B No:3
      Page(s):
    515-524

    In this paper, we propose a framework for the real-time estimation of a multidimensional QoE of Multi-View Video and Audio (MVV-A) IP transmission. The framework utilizes linear multiple regression analysis with application-level and transport-level QoS parameters which can be measured in real time. In order to cope with a variety of MVV-A usage-situations, we introduce the concept of usage-situation type for grouping usage-situations with similar features to apply a representative regression line. We deal with two contents, two camera arrangements, and two user interfaces for viewpoint change as representative examples of the usage-situations. We assess multidimensional QoE of MVV-A with various types of average load, playout buffering time, and delay in the network. We then conduct the multiple regression analysis for the multidimensional QoE values represented by a psychological scale. From the comparison of measured values and estimated ones, we notice that real-time estimation of QoE is feasible in MVV-A IP transmission.

  • Development of Microwave Kinetic Inductance Detector for Cosmological Observations Open Access

    Kenichi KARATSU  Satoru MIMA  Shugo OGURI  Jihoon CHOI  R. M. THUSHARA DAMAYANTHI  Agnes DOMINJON  Noboru FURUKAWA  Hirokazu ISHINO  Hikaru ISHITSUKA  Atsuko KIBAYASHI  Yoshiaki KIBE  Hitoshi KIUCHI  Kensuke KOGA  Masato NARUSE  Tom NITTA  Takashi NOGUCHI  Takashi OKADA  Chiko OTANI  Shigeyuki SEKIGUCHI  Yutaro SEKIMOTO  Masakazu SEKINE  Shibo SHU  Osamu TAJIMA  Kenta TAKAHASHI  Nozomu TOMITA  Hiroki WATANABE  Mitsuhiro YOSHIDA  

     
    INVITED PAPER

      Vol:
    E98-C No:3
      Page(s):
    207-218

    A precise measurement of Cosmic Microwave Background (CMB) provides us rich information about the universe. In particular, its asymmetric polarization patterns, $B$-modes, are smoking gun signature of inflationary universe. Magnitude of the $B$-modes is order of 10,nK. Its measurement requires a high sensitive millimeter-wave telescope with a large number of superconducting detectors on its focal plane. Microwave Kinetic Inductance Detector (MKID) is appropriate detector for this purpose. MKID camera has been developed in cooperation of National Astronomical Observatory of Japan (NAOJ), Institute of Physical and Chemical Research (RIKEN), High Energy Accelerator Research Organization (KEK), and Okayama University. Our developments of MKID include: fabrication of high-quality superconducting film; optical components for a camera use; and readout electronics. For performance evaluation of total integrated system of our MKID camera, a calibration system was also developed. The system was incorporated in a 0.1 K dilution refrigerator with modulated polarization source. These developed technologies are applicable to other types of detectors.

  • Response of a Superconducting Transition-Edge Sensor Microcalorimeter with a Mushroom-shaped Absorber to L X-rays Emitted by Transuranium Elements Open Access

    Keisuke MAEHATA  Makoto MAEDA  Naoko IYOMOTO  Kenji ISHIBASHI  Keisuke NAKAMURA  Katsunori AOKI  Koji TAKASAKI  Kazuhisa MITSUDA  Keiichi TANAKA  

     
    INVITED PAPER

      Vol:
    E98-C No:3
      Page(s):
    178-185

    A four-pixel-array superconducting transition-edge sensor (TES) microcalorimeter with a mushroom-shaped absorber was fabricated for the energy dispersive spectroscopy performed on a transmission electron microscope. The TES consists of a bilayer of Au/Ti with either a 50-nm or 120-nm thickness. The absorber of 5.0,$mu$m thick is made from a Au layer and its stem is deposited in the center of the TES surface. A Ta$_{2}$O$_{5}$ insulating layer of 100-nm thickness is inserted between the overhang region of the absorber and the TES surface. A selected pixel of the TES microcalorimeter was operated for the detection of Np L X-rays emitted from an $^{241}$Am source. A response of the TES microcalorimeter to L X-rays was obtained by analyzing detection signal pulses with using the optimal filter method. An energy resolution was obtained to be 33,eV of the full width at half maximum value at 17.751,keV of Np L$_{eta 1}$ considering its natural width of 13.4,eV. Response to L X-rays emitted from a mixture source of $^{238}$Pu, $^{239}$Pu and $^{241}$Am was obtained by operating the selected pixel of the TES microcalorimeter. Major L X-ray peaks of progeny elements of $alpha$ decay of Pu and Am isotopes were clearly identified in the obtained energy spectrum. The experimental results demonstrated the separation of $^{241}$Am and plutonium isotopes by L X-ray spectroscopy.

  • FOREWORD Open Access

    Hisato IWAI  

     
    FOREWORD

      Vol:
    E98-B No:3
      Page(s):
    387-387
  • Cramer-Rao Bounds for Compressive Frequency Estimation

    Xushan CHEN  Xiongwei ZHANG  Jibin YANG  Meng SUN  Weiwei YANG  

     
    LETTER-Digital Signal Processing

      Vol:
    E98-A No:3
      Page(s):
    874-877

    Compressive sensing (CS) exploits the sparsity or compressibility of signals to recover themselves from a small set of nonadaptive, linear measurements. The number of measurements is much smaller than Nyquist-rate, thus signal recovery is achieved at relatively expense. Thus, many signal processing problems which do not require exact signal recovery have attracted considerable attention recently. In this paper, we establish a framework for parameter estimation of a signal corrupted by additive colored Gaussian noise (ACGN) based on compressive measurements. We also derive the Cramer-Rao lower bound (CRB) for the frequency estimation problems in compressive domain and prove some useful properties of the CRB under different compressive measurements. Finally, we show that the theoretical conclusions are along with experimental results.

  • Blind Carrier Frequency Offset Estimation Based on Weighted Subspace Projection Approach for Interleaved OFDMA Uplink

    Ann-Chen CHANG  Chih-Chang SHEN  

     
    LETTER-Digital Signal Processing

      Vol:
    E98-A No:3
      Page(s):
    878-880

    This letter deals with the carrier frequency offsets (CFO) estimation problem for orthogonal frequency division multiple access (OFDMA) uplink systems. Combined with centro-symmetric (CS) trimmed autocorrelation matrix and weighting subspace projection, the proposed estimator has better estimate performance than MVDR, MUSIC, CS-MUSIC, and ESPRIT estimators, especially in relatively less of OFDMA blocks and low SNR situations. Simulation results are presented to verify the efficiency of the proposed estimator.

  • A Receive Beamforming Technique for a Mobile Station with Multiple Antenna Arrays in Mm-Wave Cellular Communications

    Rothna PEC  Joo Hyung CHOI  Yong Soo CHO  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E98-B No:3
      Page(s):
    456-466

    In this paper, two receive beamforming techniques (Method 1 and Method 2) are proposed for a mobile station (MS) with multiple antenna arrays in an OFDM-based millimeter-wave (mm-wave) cellular communication system. Since the MS in mm-wave cellular communication requires fast processing due to its frequent movement and rotation, a receive beamforming technique with reduced computation complexity and processing time is proposed in Method 2. Of particular interest, estimation techniques for 2-dimensional (2D) direction-of-arrivals (DoAs) corresponding to each cell ID are proposed for uniform circular arrays (UCAs) and uniform rectangular arrays (URAs). Also, a cell selection technique for MSs with multiple antenna arrays is described that use the candidate cell IDs and parameters estimated for all antenna arrays to provide combining gain in addition to array gain in multipath channels. The proposed beamforming techniques are evaluated by computer simulation using a simple model of amm-wave cellular communication system with 3-dimensional spatial channel model (3D SCM).

  • No-Reference Blur Strength Estimation Based on Spectral Analysis of Blurred Images

    Hanhoon PARK  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2014/12/19
      Vol:
    E98-D No:3
      Page(s):
    728-732

    In this letter, we propose a new no-reference blur estimation method in the frequency domain. It is based on computing the cumulative distribution function (CDF) of the Fourier transform spectrum of the blurred image and analyzing the relationship between its shape and the blur strength. From the analysis, we propose and evaluate six curve-shaped analytic metrics for estimating blur strength. Also, we employ an SVM-based learning scheme to improve the accuracy and robustness of the proposed metrics. In our experiments on Gaussian blurred images, one of the six metrics outperformed the others and the standard deviation values between 0 and 6 could be estimated with an estimation error of 0.31 on average.

  • Power Allocation for Two-Way OFDM-Based Spectrum Sharing Cognitive Radio Networks

    Ding XU  Qun LI  

     
    LETTER-Communication Theory and Signals

      Vol:
    E98-A No:3
      Page(s):
    918-922

    This paper studies the problem of power allocation for a two-way orthogonal frequency division multiplexing (OFDM) based cognitive radio (CR) network to maximize the ergodic capacities of the secondary users (SUs). Under the assumption that the SUs know the channel state information (CSI) of the interference links between the SUs and the primary user (PU) perfectly, the optimal power allocation algorithm under the interference and transmit power constraints is derived. In addition, we further assume that the SUs only know the channel distribution information (CDI) of the interference links and propose a heuristic algorithm under the interference outage and transmit power constraints based on Gaussian approximation. It is shown that the ergodic capacity with CDI is not degraded compared to that with perfect CSI under tight transmit power constraint. Moreover, it is shown that the interference outage constraint is satisfied even for very small number of subcarriers if an interference power margin is adopted for Gaussian approximation.

  • Multiple Impossible Differential Cryptanalysis on Reduced FOX

    Xinran LI  Fang-Wei FU  Xuan GUANG  

     
    LETTER-Cryptography and Information Security

      Vol:
    E98-A No:3
      Page(s):
    906-911

    FOX is a family of block ciphers published in 2004 and is famous for its provable security to cryptanalysis. In this paper, we present multiple 4-round impossible differentials and several new results of impossible differential attacks on 5,6,7-round FOX64 and 5-round FOX128 with the multiple differentials and the new early abort technique which shall reduce the data complexity and the time complexity respectively. In terms of the data complexity and the time complexity, our results are better than any of the previously known attacks.

  • Measurement of the Linewidth of a Frequency-tunable Laser Used in Optical Coherence Tomography

    Yoshifumi TAKASAKI  Keiji KURODA  Yuzo YOSHIKUNI  

     
    BRIEF PAPER-Optoelectronics

      Vol:
    E98-C No:3
      Page(s):
    275-278

    Optical coherence tomography using a tunable single-mode laser is investigated to clarify the effects of long coherence length and step-wise frequency changes.

  • On Hue-Preserving Saturation Enhancement in Color Image Enhancement

    Kohei INOUE  Kenji HARA  Kiichi URAHAMA  

     
    LETTER-Image

      Vol:
    E98-A No:3
      Page(s):
    927-931

    Recently, hue-preserving color image enhancement methods have been proposed by several researchers. However, the theoretical comparison of the performance of their methods has not been conducted yet. In this paper, we propose a hue-preserving saturation maximization method, and show a relationship of the saturation of enhanced colors by related methods. We also demonstrate the correctness of the relationship experimentally.

  • Post-Challenge Leakage Resilient Public-Key Cryptosystem in Split State Model

    Eiichiro FUJISAKI  Akinori KAWACHI  Ryo NISHIMAKI  Keisuke TANAKA  Kenji YASUNAGA  

     
    PAPER-Cryptography and Information Security

      Vol:
    E98-A No:3
      Page(s):
    853-862

    Leakage resilient cryptography is often considered in the presence of a very strong leakage oracle: An adversary may submit arbitrary efficiently computable function f to the leakage oracle to receive f(x), where x denotes the entire secret that a party possesses. This model is somewhat too strong in the setting of public-key encryption (PKE). It is known that no secret-key leakage resilient PKE scheme exists if the adversary may have access to the secret-key leakage oracle to receive only one bit after it was given the challenge ciphertext. Similarly, there exists no sender-randomness leakage resilient PKE scheme if one-bit leakage occurs after the target public key was given to the adversary. At TCC 2011, Halevi and Lin have broken the barrier of after-the-fact leakage, by proposing the so-called split state model, where a secret key of a party is explicitly divided into at least two pieces, and the adversary may have not access to the entire secret at once, but each divided pieces, one by one. In the split-state model, they have constructed post-challenge secret-key leakage resilient CPA secure PKEs from hash proof systems, but the construction of CCA secure post-challenge secret-key leakage PKE has remained open. They have also remained open to construct sender-randomness leakage PKE in the split state model. This paper provides a solution to the open issues. We also note that the proposal of Halevi and Lin is post-challenge secret-key leakage CPA secure against a single challenge ciphertext; not against multiple challenges. We present an efficient generic construction that converts any CCA secure PKE scheme into a multiple-challenge CCA secure PKE that simultaneously tolerates post-challenge secret-key and sender-randomness leakage in the split state model, without any additional assumption. In addition, our leakage amount of the resulting schemes is the same as that of Halevi and Lin CPA PKE, i.e., (1/2+γ)l/2 where l denotes the length of the entire secret (key or randomness) and γ denotes a universal (possitive) constant less than 1/2. Our conversion is generic and available for many other public-key primitives. For instance, it can convert any identity-based encryption (IBE) scheme to a post-challenge master-key leakage and sender-randomness leakage secure IBE.

  • A Practical Two-Step Friction Determination for Motion Control Using LuGre Model

    In Hyuk KIM  Young Ik SON  

     
    LETTER-Systems and Control

      Vol:
    E98-A No:3
      Page(s):
    890-893

    In order to improve the motion control performance, a new friction determination method, using the LuGre model, is proposed. The model parameters are determined by performing two-step closed-loop experiments using a proportional-integral observer (PIO). The PIO is also used to develop a robust motion controller to deal with additional uncertainties including the effect of the inaccurate estimation of the friction. The experimental results reveal improved performance compared to that of a single-PIO-based controller.

  • The Case for Network Coding for Collective Communication on HPC Interconnection Networks Open Access

    Ahmed SHALABY  Ikki FUJIWARA  Michihiro KOIBUCHI  

     
    PAPER-Information Network

      Pubricized:
    2014/12/11
      Vol:
    E98-D No:3
      Page(s):
    661-670

    Recently network bandwidth becomes a performance concern particularly for collective communication since bisection bandwidths of supercomputers become far less than their full bisection bandwidths. In this context we propose the use of a network coding technique to reduce the number of unicasts and the size of data transferred in latency-sensitive collective communications in supercomputers. Our proposed network coding scheme has a hierarchical multicasting structure with intra-group and inter-group unicasts. Quantitative analysis show that the aggregate path hop counts by our hierarchical network coding decrease as much as 94% when compared to conventional unicast-based multicasts. We validate these results by cycle-accurate network simulations. In 1,024-switch networks, the network reduces the execution time of collective communications as much as 70%. We also show that our hierarchical network coding is beneficial for any packet size.

  • Protection of On-chip Memory Systems against Multiple Cell Upsets Using Double-adjacent Error Correction Codes

    Hoyoon JUN  Yongsurk LEE  

     
    PAPER-Integrated Electronics

      Vol:
    E98-C No:3
      Page(s):
    267-274

    As semiconductor devices scale into deep sub-micron regime, the reliability issue due to radiation-induced soft errors increases in on-chip memory systems. Neutron-induced soft errors transiently upset adjacent information of multiple cells in these systems. Although single error correction and double error detection (SEC--DED) codes have been employed to protect on-chip memories from soft errors, they are not sufficient against multiple cell upsets (MCUs). SEC--DED and double adjacent error correction (SEC--DED--DAEC) codes have recently been proposed to address this problem. However, these codes do not the resolve mis-correction of double non-adjacent errors because syndromes for double non-adjacent errors are equal to that of double adjacent errors. The occurrence of this mis-correction in region of critical memory section such as operating systems may lead to system malfunction. To eliminate mis-correction, the syndrome spaces for double adjacent and double non-adjacent errors are not shared using the matrix with reversed colexicographic order. The proposed codes are implemented using hardware description language and synthesized using 32 nm technology library. The results show that there is no mis-correction in the proposed codes. In addition, the performance enhancement of the decoder is approximately 51.9% compared to double error correction codes for on-chip memories. The proposed SEC--DED--DAEC codes is suitable for protecting on-chip memory applications from MCUs-type soft errors.

  • Superconducting On-Chip Spectrometery for Millimeter-submillimeter Wave Astronomy Open Access

    Akira ENDO  

     
    INVITED PAPER

      Vol:
    E98-C No:3
      Page(s):
    219-226

    Since the birth of astrophysics, astronomers have been using free-space optics to analyze light falling on Earth. In the future however, thanks to the advances in photonics and nanoscience/nanotechnology, much of the manipulation of light might be carried out using not optics but confined waveguides, or circuits, on a chip. This new generation of instruments will be not only extremely compact, but also powerful in performance because the integration enables a greater degree of multiplexing. The benefit is especially profound for space- or air-borne observatories, where size, weight, and mechanical reliability are of top priority. Recently, several groups around the world are trying to integrate ultra-wideband (UWB), low-resolution spectrometers for millimeter-submillimeter waves onto microchips, using superconducting microelectronics. The scope of this Paper is to provide a general introduction and a review of the state-of-the-art of this rapidly advancing field.

8921-8940hit(42807hit)