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5021-5040hit(21534hit)

  • A Copyright- and Privacy-Protected Image Trading System Using Fingerprinting in Discrete Wavelet Domain with JPEG 2000

    Wannida SAE-TANG  Shenchuan LIU  Masaaki FUJIYOSHI  Hitoshi KIYA  

     
    PAPER

      Vol:
    E97-A No:11
      Page(s):
    2107-2113

    In this paper, a compression-friendly copyright- and privacy-protected image trading system is proposed. In the image trading system, the copyright of the image and the consumer's privacy is important. In addition, it should preserve existing image compression standards. In the proposed method, for privacy protection, the content provider (CP) multiplies random signs to the discrete wavelet transformed (DWTed) coefficients of an image to generate the visually encrypted image. The proposed visually protected images can be efficiently compressed by using JPEG 2000 which compresses the image in the DWTed domain as well. For copyright protection, the trusted third party (TTP) applies digital fingerprinting to the image in the encrypted domain. While in the conventional system, the amplitude-only image (AOI) which is the inversely transformed amplitude spectra of an image is used for privacy protection. Since, the AOI consists of real numbers, to store and transmit the AOI, it has to be quantized before compression. Therefore, quantization errors cannot be avoided in the conventional system. On the other hand, the proposed method applies the digital fingerprint in the DWTed domain, so clipping errors in decoding the image by the TTP is avoided. In addition, only a seed number which is input to a pseudo random number generator is shared between the CP and the consumer, whereas an extra image is shared in the conventional systems. Experimental results show that the proposed system is efficient in terms of privacy protection, compression performance, quality of fingerprinted images, and correct fingerprint extracting performance.

  • Distribution of Attention in Augmented Reality: Comparison between Binocular and Monocular Presentation Open Access

    Akihiko KITAMURA  Hiroshi NAITO  Takahiko KIMURA  Kazumitsu SHINOHARA  Takashi SASAKI  Haruhiko OKUMURA  

     
    INVITED PAPER

      Vol:
    E97-C No:11
      Page(s):
    1081-1088

    This study investigated the distribution of attention to frontal space in augmented reality (AR). We conducted two experiments to compare binocular and monocular observation when an AR image was presented. According to a previous study, when participants observed an AR image in monocular presentation, they perceived the AR image as more distant than in binocular vision. Therefore, we predicted that attention would need to be shifted between the AR image and the background in not the monocular observation but the binocular one. This would enable an observer to distribute his/her visual attention across a wider space in the monocular observation. In the experiments, participants performed two tasks concurrently to measure the size of the useful field of view (UFOV). One task was letter/number discrimination in which an AR image was presented in the central field of view (the central task). The other task was luminance change detection in which dots were presented in the peripheral field of view (the peripheral task). Depth difference existed between the AR image and the location of the peripheral task in Experiment 1 but not in Experiment 2. The results of Experiment 1 indicated that the UFOV became wider in the monocular observation than in the binocular observation. In Experiment 2, the size of the UFOV in the monocular observation was equivalent to that in the binocular observation. It becomes difficult for a participant to observe the stimuli on the background in the binocular observation when there is depth difference between the AR image and the background. These results indicate that the monocular presentation in AR is superior to binocular presentation, and even in the best condition for the binocular condition the monocular presentation is equivalent to the binocular presentation in terms of the UFOV.

  • Multicast Transmission Access Control Methods for Various Wireless LAN Applications

    Toshiyuki OGAWA  Takefumi HIRAGURI  Kentaro NISHIMORI  Hideaki YOSHINO  Kenya JIN'NO  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Vol:
    E97-B No:11
      Page(s):
    2534-2542

    In this paper, we propose an access control protocol method that maintains the communication quality of various applications and reduces packet loss of multicasts in wireless local area networks. Multicast transmission may facilitate effective bandwidth use because packets are simultaneously delivered to more than one mobile station by a single transmission. However, because multicast transmissions does not have a retransmission function, communication quality deteriorates because of packet collisions and interference waves from other systems. Moreover, although multicasts are not considered, the communication quality of each application is guaranteed by a priority control method known as enhanced distributed channel access in IEEE802.11e. The proposed method avoids both these issues. Specifically, because the proposed method first transmits the clear-to-send-to-self frame, the multicast packet avoids collision with the unicast packet. We validate the proposed method by computer simulation in an environment with traffic congestion and interference waves. The results show a reduction in multicast packet loss of approximately 20% and a higher multicast throughput improvement compared to conventional methods. Moreover, the proposed method can assure improve multicast communication quality without affecting other applications.

  • Interactive Evolutionary System for Synthesizing Facial Caricature with Non-planar Expression

    Tatsuya UGAI  Keita SATO  Kaoru ARAKAWA  Hiroshi HARASHIMA  

     
    PAPER

      Vol:
    E97-A No:11
      Page(s):
    2154-2160

    A method to synthesize facial caricatures with non-planar expression is proposed. Several methods have been already proposed to synthesize facial caricatures automatically, but they mainly synthesize plane facial caricatures which look somewhat monotonous. In order to generate expressive facial caricature, the image should be expressed in non-planar style, expressing the depth of the face by shading and highlighting. In this paper, a new method to express such non-planar effect in facial caricatures is proposed by blending the grayscale information of the real face image into the plane caricature. Some methods also have been proposed to generate non-planar facial caricature, but the proposed method can adjust the degree of non-planar expression by interactive evolutionary computing, so that the obtained expression is satisfied by the user based on his/her subjective criteria. Since the color of the face looks changed, when the grayscale information of the natural face image is mixed, the color information of the skin area are also set by interactive evolutionary computing. Experimental results show the high performance of the proposed method.

  • Network Virtualization Idealizations for Applications Open Access

    Glenn RICART  Akihiro NAKAO  

     
    INVITED PAPER

      Vol:
    E97-B No:11
      Page(s):
    2252-2258

    Due to limitations of today's widely-deployed commercial networks, some end-user applications are only possible through, or greatly improved by execution on virtualized networks that have been enhanced or idealized in a way which specifically supports the application. This paper describes US Ignite and the advantages provided to US Ignite end-user applications running on virtual networks which variously: (a) minimize latency, (b) minimize jitter, (c) minimize or eliminate packet drops, (d) optimize branch points for multicast packet duplication, (e) provide isolation for sensitive information flows, and/or (f) bundle network billing with application use. Examples of US Ignite applications in these categories are provided.

  • Adaptive Sensing Period Based Distributed Medium Access Control for Cognitive Radio Networks

    Su Min KIM  Junsu KIM  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E97-B No:11
      Page(s):
    2502-2511

    In this paper, we propose distributed medium access control (MAC) protocols based on an adaptive sensing period adjustment scheme for low-cost multiple secondary users in interweave-type cognitive radio (CR) networks. The proposed MAC protocols adjust the sensing period of each secondary user based on both primary sensing and secondary data channels in distributed manner. Then, the secondary user with the shortest sensing period accesses the medium using request-to-send (RTS) and clear-to-send (CTS) message exchange. Three components affect the length of each user's sensing period: sensing channel quality from the primary system, data channel quality to the secondary receiver, and collision probability among multiple secondary transmitters. We propose two sensing period adjustment (SPA) schemes to efficiently improve achievable rate considering the three components, which are logarithmic SPA (LSPA) and exponential SPA (ESPA). We evaluate the performance of the proposed schemes in terms of the achievable rate and other factors affecting it, such as collision probability, false alarm probability, and average sensing period.

  • Measurement of Length of a Single Tooth Using PCA-Signature and Bezier Curve

    Pramual CHOORAT  Werapon CHIRACHARIT  Kosin CHAMNONGTHAI  Takao ONOYE  

     
    PAPER

      Vol:
    E97-A No:11
      Page(s):
    2161-2169

    In developing an automatic system of a single tooth length measurement on x-ray image, since a tooth shape is assumed to be straight and curve, an algorithm which can accurately deal with straight and curve is required. This paper proposes an automatic algorithm for measuring the length of single straight and curve teeth. In the algorithm consisting of control point determination, curve fitting, and length measurement, PCA is employed to find the first and second principle axes as vertical and horizontal ones of the tooth, and two terminal points of vertical axis and the junction of those axes are determined as three first-order control points. Signature is then used to find a peak representing tooth root apex as the forth control point. Bezier curve, Euclidean distance, and perspective transform are finally applied with determined four control points in curve fitting and tooth length measurement. In the experiment, comparing with the conventional PCA-based method, the average mean square error (MSE) of the line points plotted by the expert is reduced from 7.548 pixels to 4.714 pixels for tooth image type-I, whereas the average MSE value is reduced from 7.713 pixels and 7.877 pixels to 4.809 pixels and 5.253 pixels for left side and right side of tooth image type-H, respectively.

  • New Families of p-Ary Sequences of Period $ rac{p^n-1}{2}$ with Low Maximum Correlation Magnitude

    Wijik LEE  Ji-Youp KIM  Jong-Seon NO  

     
    PAPER-Fundamental Theories for Communications

      Vol:
    E97-B No:11
      Page(s):
    2311-2315

    Let p be an odd prime such that p ≡ 3 mod 4 and n be an odd positive integer. In this paper, two new families of p-ary sequences of period $N = rac{p^n-1}{2}$ are constructed by two decimated p-ary m-sequences m(2t) and m(dt), where d=4 and d=(pn+1)/2=N+1. The upper bound on the magnitude of correlation values of two sequences in the family is derived by using Weil bound. Their upper bound is derived as $ rac{3}{sqrt{2}} sqrt{N+ rac{1}{2}}+ rac{1}{2}$ and the family size is 4N, which is four times the period of the sequence.

  • Self-Aligned Four-Terminal Planar Metal Double-Gate Low-Temperature Polycrystalline-Silicon Thin-Film Transistors for System-on-Glass Open Access

    Akito HARA  Shinya KAMO  Tadashi SATO  

     
    INVITED PAPER

      Vol:
    E97-C No:11
      Page(s):
    1048-1054

    Self-aligned four-terminal (4T) planar metal double-gate (DG) polycrystalline-silicon (poly-Si) thin-film transistors (TFTs) were fabricated on a glass substrate at a low temperature (LT), which is below $550^{circ}$C, to realize high performance and low power dissipation system-on-glass (SoG). The top gate (TG) and bottom gate (BG) were formed from tungsten (W); the BG was embedded in the glass substrate and the TG was fabricated by a self-alignment process using the BG as a photomask. This structure is called embedded metal double-gate (E-MeDG) in this paper. The poly-Si channel with lateral large grains was fabricated using a continuous-wave laser lateral crystallization (CLC). The self-aligned 4T E-MeDG LT poly-Si TFT, with a gate length of 5,$mu $m and TG and BG SiO$_2$ thicknesses of 50 and 100,nm, respectively, exhibited a subthreshold swing of 120,mV/dec and a threshold voltage ($mathrm{V}_{mathrm{th}}$) of $-$0.5,V in the connecting DG mode; i.e. when TG is connected to BG. In the TG operation at various BG control voltage, a threshold voltage modulation factor $(gamma = Delta mathrm{V}_{mathrm{th}}/Delta mathrm{V}_{mathrm{BG}})$ of 0.47 at negative BG control voltage and 0.60 at positive BG control voltage are demonstrated, which values are nearly equal to theoretical prediction of 0.40 and 0.75. Trend of subthreshold swing (s.s.) of TG operation under different BG control voltage are also consistent with theoretical prediction. In addition to TG operation, successful BG operation under various TG control voltages was confirmed. Field-effect mobility derived from g$_{mathrm{m}}$ also varied depending on control gate voltage. The high controllability of device parameter of individual LT poly-Si TFTs is caused by excellent crystalline quality of CLC poly-Si film and will enable us to the fabrication of high-speed and low power-dissipation SoG.

  • Distributed Mobility Management Scheme with Multiple LMAs in Proxy Mobile IPv6

    Won-Kyeong SEO  Jae-In CHOI  You-Ze CHO  

     
    PAPER-Network

      Vol:
    E97-B No:11
      Page(s):
    2327-2336

    The Internet Engineering Task Force (IETF) has been actively standardizing distributed mobility management (DMM) schemes with multiple Mobility Anchors (MAs). Yet, all existing schemes have limitations that preclude the efficient distribution of mobile data traffic, including single point failure problems, heavy tunneling overheads between MAs, and a restrictive traffic distribution for external nodes in a mobility domain. Therefore, this paper proposes an efficient mobility management scheme with a virtual Local Mobility Anchor (vLMA). While the vLMA is designed assuming multiple replicated LMAs for a PMIPv6 domain, it acts virtually as a single LMA for the internal and external nodes in the PMIPv6 domain. Furthermore, the vLMA distributes mobile data traffic using replicated LMAs, and routes packets via a replicated LMA on the optimal routing path. Performance evaluations confirm that the proposed scheme can distribute mobile data traffic more efficiently and reduce the end-to-end packet delay than the Distributed Local Mobility Anchor (DLMA) and the Proxy Mobile IPv6 (PMIPv6).

  • Energy-Efficient Rate Allocation for Multi-Homing Services in Heterogeneous Wireless Access Networks

    Hyeontaek OH  Joohyung LEE  Seong Gon CHOI  Jun Kyun CHOI  

     
    PAPER-Energy in Electronics Communications

      Vol:
    E97-B No:11
      Page(s):
    2316-2326

    Bandwidth aggregation (BAG) techniques have been researched for many years in an efforts to enhance throughput for multi-homed streaming service. However, despite of the considerable attention being devoted towards energy-efficient communications, the power efficiency for BAG has not been considered yet. To improve the power efficiency in multi-homed streaming service, this paper proposes Power Minimized Rate Allocation Scheme (PMRAS) with optimal rate allocation at each interface while guaranteeing an allowable packet loss rate. In developing PMRAS, we first formulate a power consumption model based on the network interface state (i.e. active and idle state). We adopt a Lagrangian algorithm to solve the convex optimization problem of power consumption. The performance results gained from a numerical analysis and simulations (NS-2) reveal that the proposed scheme offers superior performance over the existing rate allocation scheme for BAG with guaranteed required quality of service.

  • Signal Detection for EM-Based Iterative Receivers in MIMO-OFDM Mobile Communications

    Kazushi MURAOKA  Kazuhiko FUKAWA  Hiroshi SUZUKI  Satoshi SUYAMA  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E97-B No:11
      Page(s):
    2480-2490

    Joint signal detection and channel estimation based on the expectation-maximization (EM) algorithm has been investigated for multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) mobile communications over fast-fading channels. The previous work in [20] developed a channel estimation method suitable for the EM-based iterative receiver. However, it remained possible for unreliable received signals to be repetitively used during the iterative process. In order to improve the EM-based iterative receiver further, this paper proposes spatial removal from the perspective of a message-passing algorithm on factor graphs. The spatial removal performs the channel estimation of a targeted antenna by using detected signals that are obtained from the received signals of all antennas other than the targeted antenna. It can avoid the repetitive use of unreliable received signals for consecutive signal detection and channel estimation. Appropriate applications of the spatial removal are also discussed to exploit both the removal effect and the spatial diversity. Computer simulations under fast-fading conditions demonstrate that the appropriate applications of the spatial removal can improve the packet error rate (PER) of the EM-based receiver thanks to both the removal effect and the spatial diversity.

  • Spatial Division Transmission without Signal Processing for MIMO Detection Utilizing Two-Ray Fading

    Ken HIRAGA  Kazumitsu SAKAMOTO  Maki ARAI  Tomohiro SEKI  Tadao NAKAGAWA  Kazuhiro UEHARA  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E97-B No:11
      Page(s):
    2491-2501

    This paper presents a spatial division (SD) transmission method based on two-ray fading that dispenses with the high signal processing cost of multiple-input and multiple-output (MIMO) detection and antennas with narrow beamwidth. We show the optimum array geometries as functions of the transmission distance for providing a concrete array design method. Moreover, we clarify achievable channel capacity considering reflection coefficients that depend on the polarization, incident angle, and dielectric constant. When the ground surface is conductive, for two- and three-element arrays, channel capacity is doubled and tripled, respectively, over that of free space propagation. We also clarify the application limit of this method for a dielectric ground by analyzing the channel capacity's dependency on the dielectric constant. With this method, increased channel capacity by SD transmission can be obtained merely by placing antennas of wireless transceiver sets that have only SISO (single-input and single-output) capability in a two-ray propagation environment. By using formulations presented in this paper for the first time and adding discussions on the adoption of polarization multiplexing, we clarify antenna geometries of SD transmission systems using polarization multiplexing for up to six streams.

  • A Study on Minimization of Requisite Design Volume of Small Antennas Inside Handset Terminals

    Tuan Hung NGUYEN  Hiroshi SATO  Yoshio KOYANAGI  Hisashi MORISHITA  

     
    PAPER-Antennas and Propagation

      Vol:
    E97-B No:11
      Page(s):
    2395-2403

    This study presents a proposal for space-saving design of built-in antennas for handset terminals based on the concept of requisite design antenna volume. By investigating the relation between antenna input characteristic and electric near-field around the antenna element and surrounding components inside the terminal, and then evaluating the requisite design antenna volume, we propose the most effective deployment for both the antenna and surrounding components. The results show that our simple proposal can help reduced, by about 17% and 31.75%, the space that the antenna element actually requires at least for stable operation inside the terminal, in the single-band designs for the cellular 2GHz band (1920-2170MHz) and 800MHz band (830-880MHz), respectively. In the dual-band design, we verify that it can reduce, the antenna space by about 35.18%, and completely cover the two above cellular bands with good antenna performance.

  • Parameter Estimation Method Using Volterra Kernels for Nonlinear IIR Filters

    Kenta IWAI  Yoshinobu KAJIKAWA  

     
    PAPER-Digital Signal Processing

      Vol:
    E97-A No:11
      Page(s):
    2189-2199

    In this paper, we propose a parameter estimation method using Volterra kernels for the nonlinear IIR filters, which are used for the linearization of closed-box loudspeaker systems. The nonlinear IIR filter, which originates from a mirror filter, employs nonlinear parameters of the loudspeaker system. Hence, it is very important to realize an appropriate estimation method for the nonlinear parameters to increase the compensation ability of nonlinear distortions. However, it is difficult to obtain exact nonlinear parameters using the conventional parameter estimation method for nonlinear IIR filter, which uses the displacement characteristic of the diaphragm. The conventional method has two problems. First, it requires the displacement characteristic of the diaphragm but it is difficult to measure such tiny displacements. Moreover, a laser displacement gauge is required as an extra measurement instrument. Second, it has a limitation in the excitation signal used to measure the displacement of the diaphragm. On the other hand, in the proposed estimation method for nonlinear IIR filter, the parameters are updated using simulated annealing (SA) according to the cost function that represents the amount of compensation and these procedures are repeated until a given iteration count. The amount of compensation is calculated through computer simulation in which Volterra kernels of a target loudspeaker system is utilized as the loudspeaker model and then the loudspeaker model is compensated by the nonlinear IIR filter with the present parameters. Hence, the proposed method requires only an ordinary microphone and can utilize any excitation signal to estimate the nonlinear parameters. Some experimental results demonstrate that the proposed method can estimate the parameters more accurately than the conventional estimation method.

  • On the Security against Nonadaptive Chosen Ciphertext Attack and Key-Dependent Message Attack

    Jinyong CHANG  Rui XUE  

     
    LETTER-Cryptography and Information Security

      Vol:
    E97-A No:11
      Page(s):
    2267-2271

    In this letter, we formally present the definition of KDM-CCA1 security in public key setting, which falls in between the existing KDM-CPA and KDM-CCA2 security. We also prove that if a public key encryption scheme is CCA1 secure and has the properties of secret-key multiplication (or addition) homomorphism, and conditioned plaintext-restorability, then it is KDM-CCA1 secure w.r.t. two ensembles of functions that had been used in [15],[17], respectively. For concrete scheme, we show that the (tailored) Damgård's Elgamal scheme achieves this KDM-CCA1 security based on different assumptions.

  • Reusing EPR Pairs for Change of Receiver in Quantum Repeater

    Kenichiro FURUTA  

     
    LETTER-General Fundamentals and Boundaries

      Vol:
    E97-A No:11
      Page(s):
    2283-2286

    We focus on a characteristic which is specific to the quantum repeater protocol. In the quantum repeater protocol, quantum states which are generated by the protocol do not depend on receivers. Therefore, we can reuse EPR pairs which are generated before a change of a receiver for the quantum repeater protocol after the change. The purpose of reusing is advancing the finishing time of sharing EPR pairs, which is not equal to increasing the fidelity. In this paper, we construct concrete methods of reusing EPR pairs and analyze the effectiveness of reusing EPR pairs. Besides, we derive conditions in which reusing EPR pairs is effective.

  • Reducing Speech Noise for Patients with Dysarthria in Noisy Environments

    Woo KYEONG SEONG  Ji HUN PARK  Hong KOOK KIM  

     
    PAPER-Speech and Hearing

      Vol:
    E97-D No:11
      Page(s):
    2881-2887

    Dysarthric speech results from damage to the central nervous system involving the articulator, which can mainly be characterized by poor articulation due to irregular sub-glottal pressure, loudness bursts, phoneme elongation, and unexpected pauses during utterances. Since dysarthric speakers have physical disabilities due to the impairment of their nervous system, they cannot easily control electronic devices. For this reason, automatic speech recognition (ASR) can be a convenient interface for dysarthric speakers to control electronic devices. However, the performance of dysarthric ASR severely degrades when there is background noise. Thus, in this paper, we propose a noise reduction method that improves the performance of dysarthric ASR. The proposed method selectively applies either a Wiener filtering algorithm or a Kalman filtering algorithm according to the result of voiced or unvoiced classification. Then, the performance of the proposed method is compared to a conventional Wiener filtering method in terms of ASR accuracy.

  • Partial Volume Correction on ASL-MRI and Its Application on Alzheimer's Disease Diagnosis

    Wenji YANG  Wei HUANG  Shanxue CHEN  

     
    PAPER-Image Processing and Video Processing

      Vol:
    E97-D No:11
      Page(s):
    2912-2918

    Arterial spin labeling (ASL) is a non-invasive magnetic resonance imaging (MRI) method that can provide direct and quantitative measurements of cerebral blood flow (CBF) of scanned patients. ASL can be utilized as an imaging modality to detect Alzheimer's disease (AD), as brain atrophy of AD patients can be revealed by low CBF values in certain brain regions. However, partial volume effects (PVE), which is mainly caused by signal cross-contamination due to voxel heterogeneity and limited spatial resolution of ASL images, often prevents CBF in ASL from being precisely measured. In this study, a novel PVE correction method is proposed based on pixel-wise voxels in ASL images; it can well handle with the existing problems of blurring and loss of brain details in conventional PVE correction methods. Dozens of comparison experiments and statistical analysis also suggest that the proposed method is superior to other PVE correction methods in AD diagnosis based on real patients data.

  • Evaluation of Agile Software Develeopment Method for Carrier Cloud Service Platform Development

    Yoji YAMATO  Naoko SHIGEMATSU  Norihiro MIURA  

     
    LETTER-Software Engineering

      Pubricized:
    2014/08/19
      Vol:
    E97-D No:11
      Page(s):
    2959-2962

    In this paper, we evaluate a method of agile software development for carrier Cloud service platform development. It is generally said that agile software development is suitable for small-scale development, but we adopt it for the development which has more than 30 members. We attempted to enable automatic regression tests for each iteration when we adopted agile software development, so that we could start our Cloud service sufficiently fast. We compared and evaluated software reliability growth curves, regression test efforts and bug causes with waterfall development.

5021-5040hit(21534hit)