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[Keyword] RP(993hit)

681-700hit(993hit)

  • A Random-Error-Resilient Collusion-Secure Fingerprinting Code, Randomized c-Secure CRT Code

    Hajime WATANABE  Takashi KITAGAWA  

     
    PAPER-Information Security

      Vol:
    E86-A No:10
      Page(s):
    2589-2595

    In digital content distribution systems, digital watermarking (fingerprinting) technique provides a good solution to avoid illegal copying and has been studied very actively. c-Secure CRT Code is one of the most practical ID coding schemes for such fingerprinting since it is secure against collusion attacks and also secure even though random errors are furthermore added. But its usefulness is decreased in the case that random errors are added because the code length will be longer. In this paper, a new collusion attack with addition of random errors is introduced and show that c-Secure CRT Code is not sufficiently secure against the attack at first. Next, we analyze the problem and propose a new ID coding scheme, Randomized c-Secure CRT Code which overcomes the problem. As a result, this new scheme improves the error tracing probabilities against the proposed attack drastically. This new scheme has the same code length, so this is one of the most responsible fingerprinting codes for content distribution systems.

  • Design Development of SPARC64 V Microprocessor

    Mariko SAKAMOTO  Akira KATSUNO  Aiichiro INOUE  Takeo ASAKAWA  Kuniki MORITA  Tsuyoshi MOTOKURUMADA  Yasunori KIMURA  

     
    INVITED PAPER

      Vol:
    E86-D No:10
      Page(s):
    1955-1965

    We developed a SPARC-V9 processor, the SPARC64 V. It has an operating frequency of 1.35 GHz and contains 191 million transistors fabricated using 0.13-µm CMOS technology with eight-layer copper metallization. SPECjbb2000 (CPU# 32) is 492683, highest on the market and 42% higher than the next highest system. SPEC CPU2000 performance is 858 for SPECint and 1228 for SPECfp. The processor is designed to provide the high system performance and high reliability required of enterprise server systems. It is also designed to address the performance requirements of high-performance computing. During our development of several generations of mainframe processors, we conducted many related experiments, and obtained enterprise server system (EPS) development skills, an understanding of EPS workload characteristics, and technology that provides high reliability, availability, and serviceability. We used those as bases of the new processor development. The approach quite effectively moves beyond differences between mainframe and SPARC systems. At the beginning of development and before the start of hardware design, we developed a software performance simulator so we could understand the performance impacts of created specifications, thereby enabling us to make appropriate decisions about hardware design. We took this approach to solve performance problems before tape-out and avoid spending additional time on design update and physical machine reconstruction. We were successful, completing the high-performance processor development on schedule and in a short time. This paper describes the SPARC64 V microprocessor and performance analyses for development of its design.

  • Passive Geiger Mode Operation of a Si Two-Photon Absorption Avalanche Photodiode and Its Temperature Dependence

    Toshiaki KAGAWA  Suguru ARAI  

     
    PAPER

      Vol:
    E86-C No:9
      Page(s):
    1796-1799

    Competition of two-photon and one-photon absorption in Si-APD was studied. Device should be cooled down in order to clearly observe two-photon absorption at low illumination intensity. Passive Geiger mode operation was studied to sensitively detect small number of carriers generated by two-photon absorption. The illumination intensity dependence of the photocurrent pulse count number is well explained by taking into account the two absorption mechanisms and a dead time period that depends on bias voltage.

  • Corpus Based Method of Transforming Nominalized Phrases into Clauses for Text Mining Application

    Akira TERADA  Takenobu TOKUNAGA  

     
    PAPER

      Vol:
    E86-D No:9
      Page(s):
    1736-1744

    Nominalization is a linguistic phenomenon in which events usually described in terms of clauses are expressed in the form of noun phrases. Extracting event structures is an important task in text mining applications. To achieve this goal, clauses are parsed and the argument structure of main verbs are extracted from the parsed results. This kind of preprocessing has been commonly done in the past research. In order to extract event structure from nominalized phrases as well, we need to establish a technique to transform nominalized phrases into clauses. In this paper, we propose a method to transform nominalized phrases into clauses by using corpus-based approach. The proposed method first enumerates possible predicate/argument structures by referring to a nominalized phrase (noun phrase) and makes their ranking based on the frequency of each argument in the corpus. The algorithm based on this method was evaluated using a corpus consisting of 24,626 aviation safety reports in English and it achieved a 78% accuracy in transformation. The algorithm was also evaluated by applying a text mining application to extract events and their cause-effect relations from the texts. This application produced an improvement in the text mining application's performance.

  • Grain Boundary Segregation of Non-magnetic Phases during Crystallization of Co-Based Glasses

    Tae Young BYUN  Yoong OH  Chong Seung YOON  Chang Kyung KIM  

     
    PAPER

      Vol:
    E86-C No:9
      Page(s):
    1830-1834

    The segregation of non-magnetic phases such as borosilicate and Cr was investigated by crystallization behavior during the surface and bulk crystallization of Co-based amorphous alloys. The concentration of metalloids (B and Si) determined the extent of grain boundary segregation of borosilicate glass during surface crystallization. During the bulk crystallization of (Co75Cr25)0.8Si5B15 amorphous alloy, solute rejection of Cr resulted in the nucleation of Cr-deficient ferromagnetic crystals and non-magnetic σ-phase was subsequently precipitated along the grain boundary. These results show that crystallization process, i.e. nucleation and growth can be controlled to optimize the microstructure to reduce media noises in Co-based recording media.

  • Effects of Grain Size and Orientation on Magnetic Properties of CoCrPt/Ti Films for Perpendicular Magnetic Recording

    Pyungwoo JANG  Sooyoul HONG  

     
    PAPER

      Vol:
    E86-C No:9
      Page(s):
    1841-1845

    Several 2 nm seed layers were sputtered to increase coercivity (Hc) and anisotropy (Ku) of CoCrPt/Ti perpendicular recording media. Among them 2 nm Ag seed layer was very effective to increase Hc of (Co78Cr22)100-xPtx/Ti (x = 14, 20). However, the effect was more pronounced when (Co78Cr22)100-xPtx/Ti became thinner. In addition α[=4π(dM/dH)Hc] decreased when the Ag layer was used. The film thickness below which the seed Ag layer was effective was reduced with decreasing Pt content. However, the Ag seed layer did not promote (0002) texture of Ti and CoCrPt layers. Domain size was reduced when the Ag seed layer was used. The effects of Ag seed layer are thought to be due to change of exchange constant of the grains, for which the grain boundary plays an important role. Effects of film thickness and Pt content can also be explained successfully by the variation of exchange constant due to grain boundary. Some experimental evidence as well as crude mode for exchange constant variation are given.

  • A Statistical Method for Acquiring Knowledge about the Abbreviation Possibility of Some of Multiple Adnominal Phrases

    Hiroyuki SAKAI  Shigeru MASUYAMA  

     
    PAPER

      Vol:
    E86-D No:9
      Page(s):
    1710-1718

    This paper proposes a statistical method of acquiring knowledge about the abbreviation possibility of some of multiple adnominal phrases. Our method calculates weight values of multiple adnominal phrases by mutual information based on the strength of relation between the adnominal phrases and modified nouns. Among adnominal phrases, those having relatively low weight values are deleted. The evaluation of our method by experiments shows that precision attains about 84.1% and recall attains about 59.2%, respectively.

  • A Multipurpose Image Watermarking Method for Copyright Notification and Protection

    Zhe-Ming LU  Hao-Tian WU  Dian-Guo XU  Sheng-He SUN  

     
    LETTER-Applications of Information Security Techniques

      Vol:
    E86-D No:9
      Page(s):
    1931-1933

    This paper presents an image watermarking method for two purposes: to notify the copyright owner with a visible watermark, and to protect the copyright with an invisible watermark. These two watermarks are embedded in different blocks with different methods. Simulation results show that the visible watermark is hard to remove and the invisible watermark is robust.

  • Reactive ECR-Sputter-Deposition of Ni-Zn Ferrite Thin-Films for Backlayer of PMR Media

    Hirofumi WADA  Setsuo YAMAMOTO  Hiroki KURISU  Mitsuru MATSUURA  

     
    PAPER

      Vol:
    E86-C No:9
      Page(s):
    1846-1850

    A reactive sputtering method using an Electron-Cyclotron-Resonance (ECR) microwave plasma was used to deposit Ni-Zn ferrite thin-films for a soft magnetic backlayer of Co-containing spinel ferrite thin-film perpendicular magnetic recording (PMR) media. The Ni-Zn spinel ferrite thin-films with a preferential orientation of (100) and a relatively low coercivity of 15 Oe were obtained at a high deposition rate of 14 nm/min and at a temperature below 200 degrees C. Although post-annealing treatment in air at 200 degrees C was effective to decrease the coercivity of the Ni-Zn ferrite thin-films, the saturation magnetization and initial permeability decreased and the surface smoothness was deteriorated simultaneously. The Ni-Zn ferrite thin-films prepared by ECR sputtering are promising as the backlayer of the perpendicular magnetic recording medium, but further improvement is required in terms of the soft magnetic properties, the grain size and the surface roughness.

  • Robustness of Morphological Filters

    Sari PELTONEN  Pauli KUOSMANEN  

     
    PAPER-Nonlinear Signal Processing and Coding

      Vol:
    E86-A No:9
      Page(s):
    2222-2228

    In this paper our recently introduced method called output distributional influence function (ODIF) is used for the evaluation of the robustness properties of the nonlinear filter class of morphological filters. Several examples of the ODIFs for the dilation, closing and clos-opening are given and explained carefully. For each of these morphological filters the effect of filter length is examined by using the ODIFs for the expectation and variance. The robustness properties of the filters are also compared to each other and the effect of the distribution of the contamination is investigated for the closing as an example of realistic filtering conditions.

  • Quasi-Static Read/Write Tester with Sliding Reciprocation for Perpendicular Magnetic Recording

    Takayuki KUSUMI  Kiyoshi YAMAKAWA  Naoki HONDA  Kazuhiro OUCHI  

     
    PAPER

      Vol:
    E86-C No:9
      Page(s):
    1868-1873

    To develop ultra high density magnetic recording systems, a quasi-static system with a reciprocating medium motion against a stand still head was developed for a read/write tester. Double-layered perpendicular recording media and merged GMR heads assembled on a conventional head-gimbal assembly (HGA) were applied to evaluate the read/write performances. A smooth sliding contact motion was achieved, however, the head-to-medium spacing was varied depending on the head motion direction. The spacing in the reverse running direction of the conventional head slider seems to be smaller than that of the flying height in a high-speed spin stand. A merged ring head was suitable for perpendicular magnetic recording in the case of the reverse direction sliding.

  • Ultra-High-Sensitivity New Super-HARP Pickup Tube and Its Camera

    Kenkichi TANIOKA  Tomoki MATSUBARA  Yuji OHKAWA  Kazuhiro MIYAKAWA  Shiro SUZUKI  Tamotsu TAKAHATA  Norifumi EGAMI  Koichi OGUSU  Akira KOBAYASHI  Tadaaki HIRAI  Toshiaki KAWAI  Masanori HOMBO  Tetsuo YOSHIDA  

     
    INVITED PAPER

      Vol:
    E86-C No:9
      Page(s):
    1790-1795

    We have developed an ultrahigh-sensitivity "New Super-HARP" handheld camera, which has a sensitivity that is about 100 times as great as that of a CCD camera. The sensitivity of TV cameras is determined by the performance of the imaging device. We developed the world's first imaging device that achieves high sensitivity and high picture quality by using the avalanche multiplication phenomenon in an amorphous selenium photoconductive target. This "Super-HARP" pickup tube, which has already been used in TV production, has a selenium target 8-µm thick. It is about 10 times as sensitive as CCDs. We have now developed a greatly improved version of the Super-HARP tube with a target 25-µm thick. This improved version, called the New Super-HARP pickup tube, is about 10 times as sensitive as the Super-HARP pickup tube. The New Super-HARP handheld camera equipped with the new tubes has a maximum sensitivity of 11 lx at F8. This camera is a powerful tool for reporting breaking news at night and other low-light conditions, the production of scientific programs, and numerous other applications.

  • Co-containing Spinel Ferrite Thin-Film Perpendicular Magnetic Recording Media with Mn-Zn Ferrite Backlayer

    Setsuo YAMAMOTO  Hirofumi KUNIKI  Hiroki KURISU  Mitsuru MATSUURA  

     
    PAPER

      Vol:
    E86-C No:9
      Page(s):
    1835-1840

    Co-containing ferrite thin-film/Mn-Zn ferrite thin-film double-layered perpendicular media were prepared using reactive ECR sputtering and magnetron sputtering methods, and their magnetic and structural properties and recording characteristics were studied. The Mn-Zn ferrite thin-film backlayer had saturation magnetization of 3.5 kG and coercivity of 60 Oe. Reproduced voltage for the Co-containing ferrite thin-film/Mn-Zn ferrite thin-film double-layered medium was about twice of that for the Co-containing ferrite single-layer medium.

  • Effects of Grain Size Distribution in Recording Layer on SNR and Thermal Stability in Double Layered Perpendicular Media

    Sung Chul LEE  Young Wook TAHK  Taek Dong LEE  

     
    PAPER

      Vol:
    E86-C No:9
      Page(s):
    1851-1855

    In this work, micromagnetic simulations of writing and reading processes in a perpendicular system including a single pole head and recording media with soft underlayer (SUL) have been performed. The noise contribution from the recording layer increased with increasing grain size distribution of the recording layer but that from soft underlayer remained almost a constant at a given linear density. Details of the noise from the soft underlayer will be discussed. Also thermal decay over a long time scale of the recorded bits was investigated by the Langevin equation and the time-temperature scaling method. It was found that at the linear density of 1058 kfci narrower grain size distribution in the recording layer even in the same average grain size is very important in the point of thermal decay than expectation.

  • User Reactions to Anthropomorphized Interfaces

    Tomoko KODA  

     
    PAPER

      Vol:
    E86-D No:8
      Page(s):
    1369-1377

    It is still an open question whether software agents should be personified in the interface. In order to study the effects of faces and facial expressions in the interface, a series of experiments was conducted to compare subjects' responses to and evaluation of different faces and facial expressions. The experimental results obtained demonstrate that: 1) personified interfaces help users engage in a task, and are well suited for an entertainment domain; 2) people's impressions of a face in a task are different from ones of the face in isolation. Perceived intelligence of a face is determined not by the agent's appearance but by its competence; 3) there is a dichotomy between user groups which have opposite opinions about personification. Thus, agent-based interfaces should be flexible to support the diversity of users' preferences and the nature of tasks.

  • Multiple Fingerprint Set Classification for Large-Scale Personal Identification

    Kaoru UCHIDA  

     
    PAPER-Image Processing, Image Pattern Recognition

      Vol:
    E86-D No:8
      Page(s):
    1426-1435

    The applications of biometrics in the real world include various types of large-scale "one-to-many" identification, which require high performance classification technology. This paper presents a system with a classification algorithm that integrates multiple features observed in a set of fingerprints and uses them, to pre-select candidates, for more efficient personal identification from a very large fingerprint enrollment database. The algorithm determines a fingerprint's pattern type by using both ridge structure analysis and direction-based neural networks. It measures such additional feature characteristics as core-delta distance and ridge counts in parallel, along with confidence indexes associated with each feature. The pre-selector then integrates the set of obtained features from multiple fingers, after weighting them according to each feature's inherent ability to contribute to the selection process and the expected errors in observations of that feature. The system calculates the similarity between pairs of sets on the basis of feature differences, statistically evaluates the conditional probability of each pair being a correct match, and selects most similar collection of candidates for detailed matching. Experimental results confirm that it achieves an effective pre-selecting capability of 0.2% average selection (false acceptance or penetration) rate with 2% selection error (false rejection) rate.

  • Fingerprint Restoration Using Digital Reaction-Diffusion System and Its Evaluation

    Koichi ITO  Takafumi AOKI  Tatsuo HIGUCHI  

     
    PAPER

      Vol:
    E86-A No:8
      Page(s):
    1916-1924

    This paper presents an algorithm for fingerprint image restoration using Digital Reaction-Diffusion System (DRDS). The DRDS is a model of a discrete-time discrete-space nonlinear reaction-diffusion dynamical system, which is useful for generating biological textures, patterns and structures. This paper focuses on the design of a fingerprint restoration algorithm that combines (i) a ridge orientation estimation technique using an iterative coarse-to-fine processing strategy and (ii) an adaptive DRDS having a capability of enhancing low-quality fingerprint images using the estimated ridge orientation. The phase-only image matching technique is employed for evaluating the similarity between an original fingerprint image and a restored image. The proposed algorithm may be useful for person identification applications using fingerprint images.

  • Wavelet Domain Half-Pixel Motion Compensation Using H-Transform

    Yih-Ching SU  Chu-Sing YANG  Chen-Wei LEE  Chun-Wei TSENG  Yao-Jei ZHENG  

     
    LETTER-Image Processing, Image Pattern Recognition

      Vol:
    E86-D No:7
      Page(s):
    1314-1317

    Adapting to the structure of 2-D H-Transform, this paper proposes a novel wavelet domain half-pixel motion compensation algorithm HMRME (Half-pixel Multi-Resolution Motion Estimation). The primary objective of this study is the reduction of the aliasing effect caused by the down-sampling in the wavelet transform under the complexity constraints. The conventional multi-resolution motion estimation scheme can be combined with the half-pixel interpolation method to generate a new high-performance wavelet video codec. The preliminary results show that the performance of HMRME rises above its counterparts, the Multi-Resolution Motion Estimation (MRME) and the Adaptive Multi-Resolution Motion Estimation (AMRME).

  • Full-Duplex Transmission Using 2-RF-Port Electroabsorption Transceiver with Photonic Up- and Downconversions for Millimeter-Wave Radio-on-Fiber System

    Kensuke IKEDA  Toshiaki KURI  Yoshiro TAKAHASHI  Ken-ichi KITAYAMA  

     
    PAPER-Photonic Links for Wireless Communications

      Vol:
    E86-C No:7
      Page(s):
    1138-1145

    Full-duplex transmission of 60.0 GHz and 59.6 GHz millimeter-wave (mm-wave) signals of 155.52-Mbit/s differential phase shift keying (DPSK) data, radio-on-fiber (ROF) signals over 25-km-long standard single-mode fibers (SMFs) is experimentally demonstrated for the first time using a single 2-RF-port electroabsorption transceiver (EAT). The simplification of base stations (BSs) is strongly required to realize cost-effective and high-reliability mm-wave wireless access. This single EAT detects a C-band ROF signal modulated by a mm-wave downlink signal and simultaneously modulates the L-band optical carrier by a mm-wave uplink signal. The BS mainly consists of the EAT, leading to a simple and low-cost BS. Optical pilot tones and optical bandpass filters are used for photonic downconversion and photonic upconversion, to convert frequencies between mm-wave signals and intermediate frequency (IF) signals in the optical domain. With the use of optical conversions, these signals have no significant fading problems. The simultaneous transmission of both up- and downlinks has been achieved with the BER of less than 10-9. Also the fading problems due to the fiber dispersion of photonic conversions are analyzed mathematically in this paper. The single-EAT BS will become a promising candidate for a ROF access system.

  • Nonlinear Scale Spaces by Iterated Filtering of Images

    Kiichi URAHAMA  Kohei INOUE  

     
    PAPER

      Vol:
    E86-D No:7
      Page(s):
    1191-1197

    Computation of scale space images requires numerical integration of partial differential equations, which demands large computational costs especially in nonlinear cases. In this paper, we present a computational scheme for nonlinear scale spaces based on iterated filtering of original images. This scheme is found to be a special case of numerical integration with a particularly adapted integration steplength. We show the stability of the iteration with local windows and that with global ones and analyze the deformation of edge waveforms in the filtering. Computational costs are evaluated experimentally for both local and global windows and finally we apply the nonlinear multi-scale smoothing to contrast enhancement of images.

681-700hit(993hit)