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[Keyword] TE(21534hit)

12241-12260hit(21534hit)

  • Tangible Media Control System for Intuitive Interactions with Multimedia Contents

    Sejin OH  Woontack WOO  

     
    PAPER

      Vol:
    E89-D No:1
      Page(s):
    53-61

    In this paper, we present the Tangible Media Control System (TMCS), which allows users to manipulate media contents through physical objects in an intuitive way. Currently, most people access digital media contents by exploiting GUI. However, it only provides limited manipulation of the contents. The proposed system, instead of a mouse and a keyboard, adopts two types of tangible objects, i.e. a RFID-enabled object and a tracker-embedded object. The TMCS enables users to easily access and control digital media contents through tangible objects. In addition, it supports an interactive media controller which can be used to synthesize media contents according to users' taste. It also offers personalized contents, which suits users' preferences, by exploiting context such as the users' profile and situational information. Accordingly, the TMCS demonstrates that tangible interfaces with context can provide more effective interfaces to satisfy users' demands. Therefore, the proposed system can be applied to various interactive applications such as multimedia education, entertainment, multimedia editor, etc.

  • Polarimetric Scattering Analysis for a Finite Dihedral Corner Reflector

    Kei HAYASHI  Ryoichi SATO  Yoshio YAMAGUCHI  Hiroyoshi YAMADA  

     
    PAPER-Sensing

      Vol:
    E89-B No:1
      Page(s):
    191-195

    This paper examines polarimetric scattering characteristics caused by a dihedral corner reflector of finite size. The dihedral corner reflector is a basic model of double-bounce structure in urban area. The detailed scattering information serves the interpretation of Polarimetric Synthetic Aperture Radar (POLSAR) data analysis. The Finite-Difference Time-Domain (FDTD) method is utilized for the scattering calculation because of its simplicity and flexibility in the target shape modeling. This paper points out that there exists a stable double-bounce squint angle region both for perfect electric conductor (PEC) and dielectric corner reflectors. Beyond this stable squint angular region, the scattering characteristics become completely different from the assumed response. A criterion on the double-bounce scattering is proposed based on the physical optics (PO) approximation. The detailed analyses on the polarimetric index (co-polarization ratio) with respect to squint angle and an experimental result measured in an anechoic chamber are shown.

  • A Construction of Public-Key Cryptosystem Using Algebraic Coding on the Basis of Superimposition and Randomness

    Masao KASAHARA  

     
    PAPER-Public Key Cryptography

      Vol:
    E89-A No:1
      Page(s):
    47-54

    In this paper, we present a new class of public-key cryptosystem (PKC) using algebraic coding on the basis of superimposition and randomness. The proposed PKC is featured by a generator matrix, in a characteristic form, where the generator matrix of an algebraic code is repeatedly used along with the generator matrix of a random code, as sub-matrices. This generator matrix, in the characteristic form, will be referred to as K-matrix. We show that the K-matrix yields the following advantages compared with the conventional schemes: (i) It realizes an abundant supply of PKCs, yielding more secure PKCs, (ii) It realizes a short public key.

  • A Design Method of Parallel Fast RLS Second-Order Adaptive Volterra Filter

    Xueqin ZHAO  Jianming LU  Takashi YAHAGI  

     
    LETTER-Nonlinear Problems

      Vol:
    E89-A No:1
      Page(s):
    328-333

    The adaptive Volterra filter (AVF) is attractive in adaptive filtering applications because its expansion is a linear combination of the input and output signals. However, the formidable computational work of AVF is prohibitive for practical applications. In this letter, we present a parallel fast recursive least squares (RLS) second-order adaptive Volterra filter (PAVF) to reduce computational load. Our discussion is based on the approach of the fast RLS AVF [3], by which the computational complexity has been reduced to O(N3) multiplications per time instant, where O(·) denotes "order of," and N is the filter length. Proposed PAVF consists of several subfilters partitioned from the conventional AVF, with parallel implementation, the computational work can be reduced effectively. Several simulation results are presented to validate the proposed method.

  • Plaintext Simulatability

    Eiichiro FUJISAKI  

     
    PAPER-Public Key Cryptography

      Vol:
    E89-A No:1
      Page(s):
    55-65

    We propose a new security class, called plaintext simulatability, defined over the public-key encryption schemes. The notion of plaintext simulatability (denoted PS) is similar to the notion of plaintext awareness (denoted PA) defined in [3], but it is "properly" a weaker security class for public-key encryption. It is known that PA implies the class of CCA2-secure encryption (denoted IND-CCA2) but not vice versa. In most cases, PA is "unnecessarily" strong--In such cases, PA is only used to study that the public-key encryption scheme involved meets IND-CCA2, because it looks much easier to treat the membership of PA than to do "directly" the membership of IND-CCA2. We show that PS also implies IND-CCA2, while preserving such a technical advantage as well as PA. We present two novel CCA2-secure public-key encryption schemes, which should have been provided with more complicated security analyses. One is a random-oracle version of Dolev-Dwork-Naor's encryption scheme [8],[9]. Unlike the original scheme, this construction is efficient. The other is a public-key encryption scheme based on a strong pseudo-random permutation family [16] which provides the optimal ciphertext lengths for verifying the validity of ciphertexts, i.e., (ciphertext size) = (message size) + (randomness size). According to [19], such a construction remains open. Both schemes meet PS but not PA.

  • A Shape Resolution Control of Textured Object Applying Tolerance Caused by Movement

    Daisuke WAKATSUKI  Ikuo ISHII  Akira TAKAHASHI  

     
    PAPER

      Vol:
    E89-D No:1
      Page(s):
    28-36

    We propose a shape resolution control method applying a tolerance caused by movement to object's shape and texture in order to represent efficiently a textured object that has a detailed structure. It is generally difficult to perceive the error of shape or texture of the object that is moving. Our method applies this error as a tolerance. The efficient object's representation is realized by the shape resolution control that tolerates errors of contour shape and textured surface by the tolerance caused by movement and reduces object's data. It was shown better experimental results of processing time and of the quality of images in comparison with other methods. Thus, it was proved that the method applying the tolerance caused by movement to the object's shape and texture is effective in the representation of textured object that has a detailed structure.

  • Limiting the Holding Time Considering Emergency Calls in Mobile Cellular Phone Systems during Disasters

    Kazunori OKADA  

     
    PAPER-Network

      Vol:
    E89-B No:1
      Page(s):
    57-65

    During devastating natural disasters, numerous people want to make calls to check on their families and friends in the stricken areas, but many call attempts on mobile cellular systems are blocked due to limited radio frequency resources. To reduce call blocking and enable as many people as possible to access mobile cellular systems, placing a limit on the holding time for each call has been studied [1],[2]. However, during a catastrophe, emergency calls, e.g., calls to fire, ambulance, or police services are also highly likely to increase and it is important that the holding time for these calls is not limited. A method of limiting call holding time to make provision for emergency calls while considering the needs of ordinary callers is proposed. In this method, called the HTL-E method, all calls are classified as emergency calls or other according to the numbers that are dialed or the terminal numbers that are given in advance to the particular terminals making emergency calls, and only the holding time of other calls is limited. The performance characteristics of the HTL-E method were evaluated using computer simulations. The results showed that it reduced the rates of blocking and forced call termination at handover considerably, without reducing the holding time for emergency calls. The blocking rate was almost equal for emergency and other calls. In addition, the HTL-E method handles fluctuations in the demand for emergency calls flexibly. A simple method of estimating the holding-time limit for other calls, which reduces the blocking rate for emergency and other calls to the normal rate for periods of increased call demand is also presented. The calculated results produced by this method agreed well with the simulation results.

  • Simple Power Analysis on Fast Modular Reduction with Generalized Mersenne Prime for Elliptic Curve Cryptosystems

    Yasuyuki SAKAI  Kouichi SAKURAI  

     
    LETTER-Side Channel Analysis

      Vol:
    E89-A No:1
      Page(s):
    231-237

    We discuss side channel leakage from modular reduction for NIST recommended domain parameters. FIPS 186-2 has 5 recommended prime fields. These primes have a special form which is referred to as generalized Mersenne prime. These special form primes facilitate especially efficient implementation. A typical implementation of efficient modular reduction with such primes includes conditional reduction. A conditional reduction in modular reduction can constitute an information channel on the secret exponent. Several researchers have produced unified code for elliptic point addition and doubling in order to avoid a simple power analysis (SPA). However, Walter showed that SPA still be possible if Montgomery multiplication with conditional reduction is implemented within the unified code. In this paper we show SPA on the modular reduction with NIST recommended primes, combining with the unified code for elliptic point operations. As Walter stated, our results also indicate that even if the unified codes are implemented for elliptic point operations, underlying field operations should be implemented in constant time. The unified approach in itself can not be a countermeasure for side channel attacks.

  • A Fast and Accurate Algorithm for Matching Images Using Hilbert Scanning Distance with Threshold Elimination Function

    Li TIAN  Sei-ichiro KAMATA  Kazuyuki TSUNEYOSHI  Haijiang TANG  

     
    PAPER-Pattern Recognition

      Vol:
    E89-D No:1
      Page(s):
    290-297

    To find the best transformation between a "model" point set and an "image" point set is the main purpose of point pattern matching. The similarity measure plays a pivotal role and is used to determine the degree of resemblance between two objects. Although some well-known Hausdorff distance measures work well for this task, they are very computationally expensive and suffer from the noise points. In this paper, we propose a novel similarity measure using the Hilbert curve named Hilbert scanning distance (HSD) to resolve the problems. This method computes the distance measure in the one-dimensional (1-D) sequence instead of in the two-dimensional (2-D) space, which greatly reduces the computational complexity. By applying a threshold elimination function, large distance values caused by noise and position errors (e.g. those that occur with feature or edge extraction) are removed. The proposed algorithm has been applied to the task of matching edge maps with noise. The experimental results show that HSD can provide sufficient information for image matching within low computational complexity. We believe this sets a new direction for the research of point pattern recognition.

  • Computer-Aided Diagnosis of Intracranial Aneurysms in MRA Images with Case-Based Reasoning

    Syoji KOBASHI  Katsuya KONDO  Yutaka HATA  

     
    PAPER-Biological Engineering

      Vol:
    E89-D No:1
      Page(s):
    340-350

    Finding intracranial aneurysms plays a key role in preventing serious cerebral diseases such as subarachnoid hemorrhage. For detection of aneurysms, magnetic resonance angiography (MRA) can provide detailed images of arteries non-invasively. However, because over 100 MRA images per subject are required to cover the entire cerebrum, image diagnosis using MRA is very time-consuming and labor-intensive. This article presents a computer-aided diagnosis (CAD) system for finding aneurysms with MRA images. The principal components are identification of aneurysm candidates (= ROIs; regions of interest) from MRA images and estimation of a fuzzy degree for each aneurysm candidate based on a case-based reasoning (CBR). The fuzzy degree indicates whether a candidate is true aneurysm. Our system presents users with a limited number of ROIs that have been sorted in order of fuzzy degree. Thus, this system can decrease the time and the labor required for detecting aneurysms. Experimental results using phantoms indicate that the system can detect all aneurysms at branches of arteries and all saccular aneurysms produced by dilation of a straight artery in 1 direction perpendicular to the principal axis. In a clinical evaluation, performance in finding aneurysms and estimating the fuzzy degree was examined by applying the system to 16 subjects with a total of 19 aneurysms. The experimental results indicate that this CAD system detected all aneurysms except a fusiform aneurysm, and gave high fuzzy degrees and high priorities for the detected aneurysms.

  • Theme Assignment for Sentences Based on Head-Driven Patterns

    Bo-Yeong KANG  Sung-Hyon MYAENG  

     
    LETTER-Natural Language Processing

      Vol:
    E89-D No:1
      Page(s):
    377-380

    Since sentences are the basic propositional units of text, knowing their themes should help in completing various tasks such as automatic summarization requiring the knowledge about the semantic content of text. Despite the importance of determining the theme of a sentence, however, few studies have investigated the problem of automatically assigning a theme to a sentence. In this paper, we examine the notion of sentence theme and propose an automatic scheme where head-driven patterns are used for theme assignment. We tested our scheme with sentences in encyclopedia articles and obtained a promising result of 98.96% in F-score for training data and 88.57% for testing data, which outperform the baseline using all but the head-driven patterns.

  • Investigation on 10 m Semi Anechoic Chamber by Using Grid-Ferrite and Open-Top Hollow Pyramidal EM Wave Absorber

    Hiroshi KURIHARA  Toshifumi SAITO  Yoshikazu SUZUKI  Kouji NAGATA  Masaharu ADACHI  

     
    PAPER

      Vol:
    E89-C No:1
      Page(s):
    16-23

    This paper investigates the 10 m semi anechoic chamber using a new type hybrid EM wave absorber consisted of the grid-ferrite and the open-top hollow pyramidal EM wave absorber. We designed a new type hybrid EM wave absorber, which length could be slightly realized 65 cm. The 10 m semi anechoic chamber was constructed in the size of L21.5 mW13.5 mH8.9 m as the result of the ray-tracing simulation using this absorber. Then, the site attenuation in the constructed anechoic chamber was measured by using the broadband calculable dipole antennas. As the result, the maximum deviations between the measured site attenuation and theoretical calculated one were obtained within 3.6 dB in the frequency range of 30 MHz to 300 MHz. It was confirmed the validity of a new type hybrid EM wave absorber. Moreover, it was confirmed that the measured results agree with the ray-tracing simulation results, in which the differences are about 1.5 dB.

  • Full-Text and Structural Indexing of XML Documents on B+-Tree

    Toshiyuki SHIMIZU  Masatoshi YOSHIKAWA  

     
    PAPER-Contents Technology and Web Information Systems

      Vol:
    E89-D No:1
      Page(s):
    237-247

    XML query processing is one of the most active areas of database research. Although the main focus of past research has been the processing of structural XML queries, there are growing demands for a full-text search for XML documents. In this paper, we propose XICS (XML Indices for Content and Structural search), which aims at high-speed processing of both full-text and structural queries in XML documents. An important design principle of our indices is the use of a B+-tree. To represent the structural information of XML trees, each node in the XML tree is labeled with an identifier. The identifier contains an integer number representing the path information from the root node. XICS consist of two types of indices, the COB-tree (COntent B+-tree) and the STB-tree (STructure B+-tree). The search keys of the COB-tree are a pair of text fragments in the XML document and the identifiers of the leaf nodes that contain the text, whereas the search keys of the STB-tree are the node identifiers. By using a node identifier in the search keys, we can retrieve only the entries that match the path information in the query. The STB-tree can filter nodes using structural conditions in queries, while the COB-tree can filter nodes using text conditions. We have implemented a COB-tree and an STB-tree using GiST and examined index size and query processing time. Our experimental results show the efficiency of XICS in query processing.

  • A Novel Test-Bed for Immersive and Interactive Broadcasting Production Using Augmented Reality and Haptics

    Seungjun KIM  Jongeun CHA  Jongphil KIM  Jeha RYU  Seongeun EOM  Nitaigour P. MAHALIK  Byungha AHN  

     
    LETTER

      Vol:
    E89-D No:1
      Page(s):
    106-110

    In this paper, we demonstrate an immersive and interactive broadcasting production system with a new haptically enhanced multimedia broadcasting chain. The system adapts Augmented Reality (AR) techniques, which merges captured videos and virtual 3D media seamlessly through multimedia streaming technology, and haptic interaction technology in near real-time. In this system, viewers at the haptic multimedia client can interact with AR broadcasting production transmitted via communication network. We demonstrate two test applications, which show that the addition of AR- and haptic-interaction to the conventional audio-visual contents can improve immersiveness and interactivity of viewers with rich contents service.

  • Wearable Telepresence System Based on Multimodal Communication for Effective Teleoperation with a Humanoid

    Yong-Ho SEO  Hun-Young PARK  Taewoo HAN  Hyun Seung YANG  

     
    PAPER

      Vol:
    E89-D No:1
      Page(s):
    11-19

    This paper presents a new type of wearable teleoperation system that can be applied to the control of a humanoid robot. The proposed system has self-contained computing hardware with a stereo head-mounted display, a microphone, a set of headphones, and a wireless LAN. It also has a mechanism that tracks arm and head motion by using several types of sensors that detect the motion data of an operator, along with a simple force reflection mechanism that uses vibration motors at appropriate joints. For remote tasks, we use intelligent self-sensory feedback and autonomous behavior, such as automatic grasping and obstacle avoidance in a slave robot, and we feed the information back to an operator through a multimodal communication channel. Through this teleoperation system, we successfully demonstrate several teleoperative tasks, including object manipulation and mobile platform control of a humanoid robot.

  • Analysis of Absorbing Characteristics of One-Layer EM-Absorber Using CIP Method

    Shinya WATANABE  Youichi KAKUTA  Osamu HASHIMOTO  

     
    PAPER

      Vol:
    E89-C No:1
      Page(s):
    51-60

    In this paper, Constrained Interpolation Profile (CIP) method is applied to Maxwell's equation including complex permittivity and permeability and the validity of CIP method applied to the equation is confirmed compared with the FDTD method. And the dependency on CFL (Courant-Friedrich-Lewy) condition, cell size and estimates of , and of the absorbing characteristics of one-layer EM-absorber are calculated using CIP method and compared with that by FDTD method. As a result, it is confirmed that the characteristics obtained by CIP method is different from that by FDTD method.

  • A Synchronization and Cell Searching Technique Using Pilot Tones for OFDM Cellular Systems

    Dong Han KIM  Kwang Soon KIM  Jae Young AHN  Yong Soo CHO  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E89-B No:1
      Page(s):
    235-238

    In this letter, a pilot structure and an efficient algorithm for downlink synchronization and cell searching in OFDM-based cellular systems are proposed. The pilots, randomly allocated in the frequency domain, allow us to minimize inter-cell interference (ICI) as well as to increase cell searching capability, estimation range of integer carrier frequency offset (CFO), and estimation accuracy of symbol timing offset (STO). The proposed low-complexity joint algorithm for integer CFO estimation, cell searching, and downlink detection is robust to ICI, multipath channel, STO and fine CFO.

  • Adaptive Search Range Decision and Early Termination for Multiple Reference Frame Motion Estimation for H.264

    Gwo-Long LI  Mei-Juan CHEN  

     
    LETTER-Multimedia Systems for Communications" Multimedia Systems for Communications

      Vol:
    E89-B No:1
      Page(s):
    250-253

    The newest video coding standard called H.264 provides considerable performance improvement over a wide range of bit rates and video resolutions compared to previous standards. However, these features result in an extraordinary increase in encoder complexity, mainly regarding to mode decision and multiple reference frame motion estimation (ME). This letter presents two algorithms to reduce the computational complexity caused by motion estimation. The adaptive search range decision method determines the search range size according to the motion vector predictor dynamically and the early termination scheme defines a criterion to early terminate the search processing for multiple reference frames. Experimental results show that the proposed algorithms provide significant improvement of coding speed with negligible objective quality degradation compared to the fast motion estimation algorithms adopted by reference software.

  • A Reliable New 2-Stage Distributed Interactive TGS System Based on GIS Database and Augmented Reality

    Seungjun KIM  Hojung KIM  Seongeun EOM  Nitaigour P. MAHALIK  Byungha AHN  

     
    LETTER

      Vol:
    E89-D No:1
      Page(s):
    98-105

    Most of the traveller guidance services (TGS) are based on GPS technology and generally concerned with the position data mapping on the simplified 2D electronic map in order to provide macro level service facility such as drive direction notifications. Digital GIS based GPS entails in situ intuitive visualization. The visually enhanced TGS can improve the global and local awareness of unknown areas. In this paper, we propose a reliable new TGS system that provides 3D street as well as pin-pointed destination information in two stages of its interactive services; web-based and AR-based. The web server generates a guiding path on 2D digital map and displays 3D car-driving animation along the path. And, the AR-based service is embedded so that users can interactively obtain the detailed micro-level information of a specific section in the area with their fingertips. The implementation is based on autoformation of on-line GIS data structures from the available priori. For the verification, a 54 road network is selected as a test area. In the service demonstration, we show the effective awareness of street environments and the usefulness of this new TGS system.

  • Suppression Effect by Conducting Plate under Ground Plane for Emission from Printed Circuit Board

    Teruo TOBANA  Takayuki SASAMORI  Kohshi ABE  

     
    PAPER

      Vol:
    E89-C No:1
      Page(s):
    38-43

    For emission from a printed circuit board (PCB) by the common-mode current, the suppression method based on the image theory by placing a conducting plate under the PCB is presented. In order to evaluate the suppression effect by this method the radiation power from the PCB is calculated by using FDTD method. The numerical results show that placing the conducting plate suppresses the emission by the common-mode current. Especially, using the conducting plate bent the sides, it is possible to suppress the emission by the small conducting plate. Further, the experimental results of a radiation power and a maximum electric field intensity show the validity of the numerical results.

12241-12260hit(21534hit)