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[Keyword] ATI(18690hit)

9161-9180hit(18690hit)

  • RCS Prediction Method from One-Dimensional Intensity Data in Near-Field

    Yoshio INASAWA  Hiroaki MIYASHITA  Yoshihiko KONISHI  

     
    LETTER-Electromagnetic Theory

      Vol:
    E91-C No:7
      Page(s):
    1167-1170

    Radar Cross Section (RCS) can be obtained from near-field data by using near-field to far-field RCS transformation methods. Phase errors in near-field data cause the degradation of the prediction accuracy. In order to overcome the difficulty, we propose the far-field RCS prediction method from one-dimensional intensity data in near-field. The proposed method is derived by extending the phase retrieval method based on the Gerchberg-Saxton algorithm with the use of the relational expression between near-fields and scattering coefficients. The far-field RCS can be predicted from the intensity data of scattered fields measured at two different ranges. The far-field RCS predicted by the proposed method approximately coincides with the computed one. The proposed method also has significant advantages of simple and efficient algorithm. The proposed method is valuable from a practical point of view.

  • Study of Facial Features Combination Using a Novel Adaptive Fuzzy Integral Fusion Model

    M. Mahdi GHAZAEI ARDAKANI  Shahriar BARADARAN SHOKOUHI  

     
    PAPER

      Vol:
    E91-D No:7
      Page(s):
    1863-1870

    A new adaptive model based on fuzzy integrals has been presented and used for combining three well-known methods, Eigenface, Fisherface and SOMface, for face classification. After training the competence estimation functions, the adaptive mechanism enables our system the filtering of unsure judgments of classifiers for a specific input. Comparison with classical and non-adaptive approaches proves the superiority of this model. Also we examined how these features contribute to the combined result and whether they can together establish a more robust feature.

  • Fast Searching Algorithm for Vector Quantization Based on Subvector Technique

    ShanXue CHEN  FangWei LI  WeiLe ZHU  TianQi ZHANG  

     
    PAPER-Image Processing and Video Processing

      Vol:
    E91-D No:7
      Page(s):
    2035-2040

    A fast algorithm to speed up the search process of vector quantization encoding is presented. Using the sum and the partial norms of a vector, some eliminating inequalities are constructeded. First the inequality based on the sum is used for determining the bounds of searching candidate codeword. Then, using an inequality based on subvector norm and another inequality combining the partial distance with subvector norm, more unnecessary codewords are eliminated without the full distance calculation. The proposed algorithm can reject a lot of codewords, while introducing no extra distortion compared to the conventional full search algorithm. Experimental results show that the proposed algorithm outperforms the existing state-of-the-art search algorithms in reducing the computational complexity and the number of distortion calculation.

  • Real-Time Tracking Error Estimation for Augmented Reality for Registration with Linecode Markers

    Zhiqiang BIAN  Hirotake ISHII  Hiroshi SHIMODA  Masanori IZUMI  

     
    PAPER-Image Recognition, Computer Vision

      Vol:
    E91-D No:7
      Page(s):
    2041-2050

    Augmented reality tasks require a high-reliability tracking method. Large tracking error causes many problems during AR applications. Tracking error estimation should be integrated with them to improve the reliability of tracking methods. Although some tracking error estimation methods have been developed, they are not feasible to be integrated because of computational speed and accuracy. For this study, a tracking error estimation algorithm with screen error estimation based on the characteristic of linecode marker was applied. It can rapidly estimate tracking error. An evaluation experiment was conducted to compare the estimated tracking error and the actual measured tracking error. Results show that the algorithm is reliable and sufficiently fast to be used for real-time tracking error warning or tracking accuracy improvement methods.

  • A Novel Hardware Architecture of Intra-Predictor Generator for H.264/AVC Codec

    Sanghoon KWAK  Jinwook KIM  Dongsoo HAR  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E91-D No:7
      Page(s):
    2083-2086

    The intra-prediction unit is an essential part of H.264 codec, since it reduces the amount of data to be encoded by predicting pixel values (luminance and chrominance) from their neighboring blocks. A dedicated hardware implementation for the intra-prediction unit is required for real-time encoding and decoding of high resolution video data. To develop a cost-effective intra-prediction unit this paper proposes a novel architecture of intra-predictor generator, the core part of intra-prediction unit. The proposed intra-predictor generator enables the intra-prediction unit to achieve significant clock cycle reduction with approximately the same gate count, as compared to Huang's work [3].

  • Color Constancy Based on Effective Regions

    Rui LU  De XU  Xinbin YANG  Bing LI  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E91-D No:7
      Page(s):
    2091-2094

    None of the existing color constancy algorithms can be considered universal. Furthermore, they use all the image pixels, although actually not all of the pixels are effective in illumination estimation. Consequently, how to select a proper color constancy algorithm from existing algorithms and how to select effective(or useful) pixels from an image are two most important problems for natural images color constancy. In this paper, a novel Color Constancy method using Effective Regions (CCER) is proposed, which consists of the proper algorithm selection and effective regions selection. For a given image, the most proper algorithm is selected according to its Weilbull distribution while its effective regions are chosen based on image similarity. The experiments show promising results compared with the state-of-the-art methods.

  • Midpoint-Validation Method for Support Vector Machine Classification

    Hiroki TAMURA  Koichi TANNO  

     
    LETTER-Biocybernetics, Neurocomputing

      Vol:
    E91-D No:7
      Page(s):
    2095-2098

    In this paper, we propose a midpoint-validation method which improves the generalization of Support Vector Machine. The proposed method creates midpoint data, as well as a turning adjustment parameter of Support Vector Machine using midpoint data and previous training data. We compare its performance with the original Support Vector Machine, Multilayer Perceptron, Radial Basis Function Neural Network and also tested our proposed method on several benchmark problems. The results obtained from the simulation shows the effectiveness of the proposed method.

  • Development of Mentalizing and Communication: From Viewpoint of Developmental Cybernetics and Developmental Cognitive Neuroscience Open Access

    Shoji ITAKURA  

     
    INVITED PAPER

      Vol:
    E91-B No:7
      Page(s):
    2109-2117

    The ability to mentalize is essential for human socialization. Such ability is strongly related to communication. In this paper, I discuss the development of mentalizing and communication from the perspectives of a new idea, Developmental Cybernetics, and developmental cognitive neuroscience. Children only attributed intention to a robot when they saw it behaving as a human and displaying social signals such as eye gaze. The emergence of powerful new methods and tools, such as neuroimaging, now allows questions about mentalizing to resolved more directly than before.

  • Quantitative Characterization of Surface Amino Groups of Plasma-Polymerized Films Prepared from Nitrogen-Containing Monomers for Bioelectronic Applications

    Hitoshi MUGURUMA  

     
    PAPER-Organic Molecular Electronics

      Vol:
    E91-C No:6
      Page(s):
    963-967

    The surface amino groups of plasma-polymerized films prepared from various nitrogen-containing monomers were quantitatively characterized for bioelectronic and biomedical applications. X-ray photoelectron spectroscopy (XPS) measurements were conducted on two kinds of surfaces: pristine surfaces of plasma-polymerized film prepared using various nitrogen-containing monomers, and theirs surfaces whose amino groups had been derivatized by a primary-amine-selective reagent carrying an XPS label. The XPS data showed that the maximum surface density of amino groups for this film was 8.41013 cm-2. Amino groups constituted 14-64% of all surface nitrogen atoms (NH/N), depending on the monomer used.

  • A Two-Microphone Noise Reduction Method in Highly Non-stationary Multiple-Noise-Source Environments

    Junfeng LI  Masato AKAGI  Yoiti SUZUKI  

     
    PAPER

      Vol:
    E91-A No:6
      Page(s):
    1337-1346

    In this paper, we propose a two-microphone noise reduction method to deal with non-stationary interfering noises in multiple-noise-source environments in which the traditional two-microphone algorithms cannot function well. In the proposed algorithm, multiple interfering noise sources are regarded as one virtually integrated noise source in each subband, and the spectrum of the integrated noise is then estimated using its virtual direction of arrival. To do this, we suggest a direction finder for the integrated noise using only two microphones that performs well even in speech active periods. The noise spectrum estimate is further improved by integrating a single-channel noise estimation approach and then subtracted from that of the noisy signal, finally enhancing the desired target signal. The performance of the proposed algorithm is evaluated and compared with the traditional algorithms in various conditions. Experimental results demonstrate that the proposed algorithm outperforms the traditional algorithms in various conditions in terms of objective and subjective speech quality measures.

  • Mechanism of Perceptual Categorization in the Pre-Linguistic Period

    Tamami SUDO  Ken MOGI  

     
    PAPER-Human Information Processing

      Vol:
    E91-D No:6
      Page(s):
    1649-1655

    In this study, we conducted a series of experiments using stimuli characterized by various attributes in order to understand the categorization process in an infant's pre-linguistic development. The infants are able to assign the same label to members within the same category by focusing attention on specific features or functions common to the members. The ability to categorize is likely to play an essential role in an infant's overall cognitive development. Specifically, we investigated how the infants use different strategies in the process of linguistic categorization. In one strategy, members of a single category are derived from perceptual similarities within the most representative members, i.e., the prototypical members. Alternatively, each membership is established by referring to the linguistic labels for each category provided by the caretaker, in a symbol grounding process. We found that the infant is able to employ these strategies in a flexible manner in its development. We discuss the interplay between different cognitive strategies, including the prototype effects in the infant's cognitive development and the implications for cortical mechanism involved.

  • Control of Speed and Power in a Humanoid Robot Arm Using Pneumatic Actuators for Human-Robot Coexisting Environment

    Kiyoshi HOSHINO  

     
    PAPER-Interface Design

      Vol:
    E91-D No:6
      Page(s):
    1693-1699

    A new type of humanoid robot arm which can coexist and be interactive with human beings are looked for. For the purpose of implementation of human smooth and fast movement to a pneumatic robot, the author used a humanoid robot arm with pneumatic agonist-antagonist actuators as endoskeletons which has control mechanism in the stiffness of each joint, and the controllability was experimentally discussed. Using Kitamori 's method to experimentally decide the control gains and using I-PD controller, three joints of the humanoid robot arm were experimentally controlled. The damping control algorithm was also adopted to the wrist joint, to modify the speed in accordance with the power. The results showed that the controllability to step-wise input was less than one degree in error to follow the target angles, and the time constant was less than one second. The simultaneous input of command to three joints was brought about the overshoot of about ten percent increase in error. The humanoid robot arm can generate the calligraphic motions, moving quickly at some times but slowly at other times, or particularly softly on some occasions but stiffly on other occasions at high accuracy.

  • Selection of the BEM Order in the Estimation of the Doubly-Selective Channel

    Lidong WANG  Dongmin LIM  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E91-B No:6
      Page(s):
    2037-2040

    In this letter, we focus on the selection of the BEM order in the doubly-selective channel estimation. Based on the Jakes' channel model, we take into account the channel spectrum spread caused by observation window effects and the channel estimation error, and propose a method of selecting the optimal BEM order in the sense of minimum mean square error.

  • A Masking Model for Motion Sharpening Phenomenon in Video Sequences

    Akira FUJIBAYASHI  Choong Seng BOON  

     
    PAPER

      Vol:
    E91-A No:6
      Page(s):
    1408-1415

    In this paper, we show that motion sharpening phenomenon can be explained as a form of visual masking for a special case where a video sequence is composed of alternate frames with different level of sharpness. A frame of higher sharpness behaves to mask the ambiguity of a subsequent frame of lower sharpness and hence preserves the perceptive quality of the whole sequence. Borrowing the mechanism for visual masking, we formulated a quantitative model for deriving the minimum spatial frequency conditions which preserves the subjective quality of the frames being masked. The quantitative model takes into account three fundamental properties of the video signals, namely the size of motion, average luminance and the power of each frequency components. The psychophysical responses towards the changes of these properties are obtained through subjective assessment tests using video sequences of simple geometrical patterns. Subjective experiments on natural video sequences show that more than 75% of viewers could make no distinction between the original sequence and the one processed using the quantitative model.

  • Prototyping Tool for Web-Based Multiuser Online Role-Playing Game

    Shusuke OKAMOTO  Masaru KAMADA  Tatsuhiro YONEKURA  

     
    LETTER-Interface Design

      Vol:
    E91-D No:6
      Page(s):
    1700-1703

    This letter proposes a prototyping tool for Web-based Multiuser Online Role-Playing Game (MORPG). The design goal is to make this tool simple and powerful. The tool is comprised of a GUI editor, a translator and a runtime environment. The GUI editor is used to edit state-transition diagrams, each of which defines the behavior of the fictional characters. The state-transition diagrams are translated into C program codes, which plays the role of a game engine in RPG system. The runtime environment includes PHP, JavaScript with Ajax and HTML. So the prototype system can be played on the usual Web browser, such as Firefox, Safari and IE. On a click or key press by a player, the Web browser sends it to the Web server to reflect its consequence on the screens which other players are looking at. Prospected users of this tool include programming novices and schoolchildren. The knowledge or skill of any specific programming languages is not required to create state-transition diagrams. Its structure is not only suitable for the definition of a character behavior but also intuitive to help novices understand. Therefore, the users can easily create Web-based MORPG system with the tool.

  • Holistic Design in mm-Wave Silicon ICs

    Ali HAJIMIRI  

     
    INVITED PAPER

      Vol:
    E91-C No:6
      Page(s):
    817-828

    Millimeter-waves integrated circuits offer a unique opportunity for a holistic design approach encompassing RF, analog, and digital, as well as radiation and electromagnetics. The ability to deal with the complete system covering a broad range from the digital circuitry to on-chip antennas and everything in between offers unparalleled opportunities for completely new architectures and topologies, which were previously impossible due the traditional partitioning of various blocks in conventional design. This can open a plethora of new architectural and system level innovation within the integrated circuit platform. This paper reviews some of the challenges and opportunities for mm-wave ICs and presents several solutions to them.

  • A Low Distortion and Low Noise Differential Amplifier Suitable for 3G LTE Applications Using the Even- and Odd-Mode Impedance Differences of a Bias Circuit

    Toshifumi NAKATANI  Koichi OGAWA  

     
    PAPER

      Vol:
    E91-C No:6
      Page(s):
    844-853

    A low distortion and low noise differential amplifier using the difference between the even- and odd-mode impedances is proposed. In order to realize an amplifier with high OIP3 and low NF characteristics, the impedance of the bias circuit should be low (<300 Ω) at the difference frequency and high (>4 kΩ) at the carrier frequency. Although the frequency response of the bias circuit impedance can only meet these conditions with difficulty, owing to the 20 MHz Tx signal bandwidth for 3G LTE, the proposed amplifier can achieve the impedance difference using the properties of a differential configuration where the difference frequency signal is the even-mode and the carrier frequency is the odd-mode. It has been demonstrated that the NF of the proposed amplifier, which has been fabricated in 0.18 µm SiGe BiCMOS technology operating at 2.14 GHz, can be kept to 1.6 dB or less and an OIP3 of 9.0 dBm can be achieved, which is 3 dB higher than that of a conventional amplifier, in the condition where the power gain is greater than 18 dB.

  • Performance Comparison of Detection Methods for Combined STBC and SM Systems

    Xuan Nam TRAN  Huan Cong HO  Tadashi FUJINO  Yoshio KARASAWA  

     
    PAPER-Smart Antennas & MIMO

      Vol:
    E91-B No:6
      Page(s):
    1734-1742

    This paper considers detection schemes for the combined space-time block coding and spatial multiplexing (STBC-SM) transmission systems. We propose a symbol detection scheme which allows to extend the limit on the number of transmit antennas imposed by the previous group detection scheme. The proposed scheme allows to double multiplexing gain as well as provides better bit error rate (BER) performance over the group detection scheme. It is shown that the proposed QR-SIC (combined QR-decomposition and successive interference cancellation) symbol detector provides good trade-off between the BER and computational complexity performance and, thus, is the most suitable detector for the combined STBC-SM system.

  • A Method to Transform Rainfall Rate to Rain Attenuation and Its Application to 21 GHz Band Satellite Broadcasting

    Susumu NAKAZAWA  Shoji TANAKA  Kazuyoshi SHOGEN  

     
    PAPER-Propagation

      Vol:
    E91-B No:6
      Page(s):
    1806-1811

    Satellite broadcasting in the 21-GHz band is expected to transmit large-capacity signals such as ultrahigh-definition TV. However, this band suffers from large amounts of rain attenuation. In this regard, we have been studying rain fading mitigation techniques, in which the radiation power is increased locally in the area of heavy rainfall. To design such a satellite broadcasting system, it is necessary to evaluate service availability when using the locally increased beam technique. The rain attenuation data should be derived from the rainfall rate data. We developed a method to transform rainfall rate into rain attenuation in the 21 GHz band. Then, we performed a simulation that applied the method to the analysis of the service availability for an example phased array antenna configuration. The results confirmed the service availability increased with the locally increased beam technique.

  • Jigsaw-Puzzle-Like 3D Glyphs for Visualization of Grammatical Constraints

    Noritaka OSAWA  

     
    PAPER-Computer Graphics

      Vol:
    E91-D No:6
      Page(s):
    1804-1812

    Three-dimensional visualization using jigsaw-puzzle-like glyphs, or shapes, is proposed as a means of representing grammatical constraints in programming. The proposed visualization uses 3D glyphs such as convex, concave, and wireframe shapes. A semantic constraint, such as a type constraint in an assignment, is represented by an inclusive match between 3D glyphs. An application of the proposed visualization method to a subset of the Java programming language is demonstrated. An experimental evaluation showed that the 3D glyphs are easier to learn and enable users to more quickly understand their relationships than 2D glyphs and 1D symbol sequences.

9161-9180hit(18690hit)