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10321-10340hit(20498hit)

  • A New Meta-Criterion for Regularized Subspace Information Criterion

    Yasushi HIDAKA  Masashi SUGIYAMA  

     
    PAPER-Pattern Recognition

      Vol:
    E90-D No:11
      Page(s):
    1779-1786

    In order to obtain better generalization performance in supervised learning, model parameters should be determined appropriately, i.e., they should be determined so that the generalization error is minimized. However, since the generalization error is inaccessible in practice, the model parameters are usually determined so that an estimator of the generalization error is minimized. The regularized subspace information criterion (RSIC) is such a generalization error estimator for model selection. RSIC includes an additional regularization parameter and it should be determined appropriately for better model selection. A meta-criterion for determining the regularization parameter has also been proposed and shown to be useful in practice. In this paper, we show that there are several drawbacks in the existing meta-criterion and give an alternative meta-criterion that can solve the problems. Through simulations, we show that the use of the new meta-criterion further improves the model selection performance.

  • 3D Keyframe Animation Watermarking Based on Orientation Interpolator

    Suk-Hwan LEE  Ki-Ryong KWON  

     
    PAPER-Application Information Security

      Vol:
    E90-D No:11
      Page(s):
    1751-1761

    This paper presents 3D keyframe animation watermarking using orientation interpolators. 3D keyframe animation consists of a number of transform nodes, including a geometrical node from the initial model and several interpolator nodes that represent object movement. Therefore, the proposed algorithm randomly selects transform nodes with orientation interpolator nodes, then resamples the quaternion components to maintain a uniform key time. Thereafter, watermark bits are embedded into quaternion components with large rotation angles. Experimental results verify the robustness of the proposed algorithm to geometrical and timeline attacks, along with the subjective and objective quality of its invisibility.

  • A Static Bug Detector for Uninitialized Field References in Java Programs

    Sunae SEO  Youil KIM  Hyun-Goo KANG  Taisook HAN  

     
    PAPER-Software Engineering

      Vol:
    E90-D No:10
      Page(s):
    1663-1671

    Correctness of Java programs is important because they are executed in distributed computing environments. The object initialization scheme in the Java programming language is complicated, and this complexity may lead to undesirable semantic bugs. Various tools have been developed for detecting program patterns that might cause errors during program execution. However, current tools cannot identify code patterns in which an uninitialized field is accessed when an object is initialized. We refer to such erroneous patterns as uninitialized field references. In this paper, we propose a static pattern detection algorithm for identifying uninitialized field references. We design a sound analysis for this problem and implement an analyzer using the Soot framework. In addition, we apply our algorithm to some real Java applications. From the experiments, we identify 12 suspicious field references in the applications, and among those we find two suspected errors by manual inspection.

  • An Intrablog-Based Informal Communication Encouraging System that Seamlessly Links On-Line Communications to Off-Line Ones

    Yoshihito CHIBA  Kazushi NISHIMOTO  

     
    PAPER

      Vol:
    E90-D No:10
      Page(s):
    1501-1508

    In this paper, we propose an intrablog-based informal communication encouraging system named "Attractiblog." It has been pointed out that daily informal communications at a shared public space play very important role in information sharing in an organization. However, in most cases, the communications are often mere chats. To make the communications more informative, it is necessary to feed some common and beneficial topics there. Attractiblog is a system that extracts some articles posted in an intrablog considering who are in the shared space, and show them on a large-sized display that is located in the space. Thus, Attractiblog attempts to seamlessly link on-line communications to off-line communications. We conducted user studies and confirmed that Attractiblog can achieve a natural correspondence between topics in face-to-face informal communications and issues related to the activities of an organization as given in its intrablog.

  • On Reachability Analysis of Multi Agent Nets

    Toshiyuki MIYAMOTO  Masaki SAKAMOTO  Sadatoshi KUMAGAI  

     
    LETTER-Systems Theory and Control

      Vol:
    E90-A No:10
      Page(s):
    2257-2260

    Petri nets are known as a modeling language for concurrent and distributed systems. In recent years, various object-oriented Petri nets were proposed, and we are proposing a kind of object-oriented Petri nets, called multi agent nets (MANs). In this letter, we consider the reachability analysis of MANs. We propose an algorithm for generating an abstract state space of a multi agent net, and report results of computational experiments.

  • A Hierarchical Service Management System for MPLS Network Services

    Kenji KUMAKI  Ikuo NAKAGAWA  Kenichi NAGAMI  Tomohiko OGISHI  Shigehiro ANO  

     
    PAPER

      Vol:
    E90-B No:10
      Page(s):
    2764-2771

    This paper proposes a hierarchical service management system for MPLS network services. Traditionally, general management systems which have been deployed in some service providers control MPLS LSPs (e.g. RSVP-TE, LDP) and services (e.g. L2VPN, L3VPN and IP) separately. If a fault occurs in an MPLS network, the dedicated management system for MPLS LSPs can detect the fault and recognize the state of MPLS LSPs. However, it cannot detect the extent of the impact due to the fault in each service. Furthermore, its own inability to identify the affected customer means it takes some time to identify the affected customers, cooperating manually with the dedicated management system for services. Therefore, this paper proposes a new automatic correlation between MPLS LSPs and each service. In particular, this paper proposes a new algorithm for a correlation between RSVP-TE LSPs and L3VPN services. Simulations are conducted to evaluate the capacity on a correlation table and the performance searching on a correlation table, and results show this system is very scalable within real MPLS production networks. This system, with the automatic correlation, could be sufficiently deployed in real MPLS production networks.

  • Evaluation of Reliable Multicast Applications for Large-Scale Contents Delivery

    Teruji SHIROSHITA  Shingo KINOSHITA  Takahiko NAGATA  Tetsuo SANO  Yukihiro NAKAMURA  

     
    PAPER

      Vol:
    E90-B No:10
      Page(s):
    2738-2745

    Reliable Multicast has been applied to large-scale contents delivery systems for distributing digital contents to a large number of users without data loss. Reliable contents distribution is indispensable for software updates and management data sharing in actual delivery services. This paper evaluates the implementation and performance of RMTP; a reliable multicast protocol for bulk-data transfer, through the developments of contents delivery systems. Software configuration is also examined including operation functions such as delivery scheduling. Furthermore, applicability of reliable multicast to emerging broadband networks is also discussed based on the experimentation results. Through the deployment of the protocol and the software, performance estimation has played a key role for constructing the delivery systems as well as for designing the communication protocol.

  • Improving Search Performance: A Lesson Learned from Evaluating Search Engines Using Thai Queries

    Shisanu TONGCHIM  Virach SORNLERTLAMVANICH  Hitoshi ISAHARA  

     
    PAPER

      Vol:
    E90-D No:10
      Page(s):
    1557-1564

    This study initiates a systematic evaluation of web search engine performance using queries written in Thai. Statistical testing indicates that there are some significant differences in the performance of search engines. In addition to compare the search performance, an analysis of the returned results is carried out. The analysis of the returned results shows that the majority of returned results are unique to a particular search engine and each system provides quite different results. This encourages the use of metasearch techniques to combine the search results in order to improve the performance and reliability in finding relevant documents. We examine several metasearch models based on the Borda count and Condorcet voting schemes. We also propose the use of Evolutionary Programming (EP) to optimize weight vectors used by the voting algorithms. The results show that the use of metasearch approaches produces superior performance compared to any single search engine on Thai queries.

  • Automatic Extraction of the Fine Category of Person Named Entities from Text Corpora

    Tri-Thanh NGUYEN  Akira SHIMAZU  

     
    PAPER

      Vol:
    E90-D No:10
      Page(s):
    1542-1549

    Named entities play an important role in many Natural Language Processing applications. Currently, most named entity recognition systems rely on a small set of general named entity (NE) types. Though some efforts have been proposed to expand the hierarchy of NE types, there are still a fixed number of NE types. In real applications, such as question answering or semantic search systems, users may be interested in more diverse specific NE types. This paper proposes a method to extract categories of person named entities from text documents. Based on Dual Iterative Pattern Relation Extraction method, we develop a more suitable model for solving our problem, and explore the generation of different pattern types. A method for validating whether a category is valid or not is proposed to improve the performance, and experiments on Wall Street Journal corpus give promising results.

  • Replicator Dynamics with Government's Intervention by Collection and Reallocation of Payoffs

    Takafumi KANAZAWA  Toshimitsu USHIO  Hayato GOTO  

     
    PAPER-Nonlinear Phenomena and Analysis

      Vol:
    E90-A No:10
      Page(s):
    2170-2177

    In a community which consists of a large number of people interacting with each other, social dilemma is an important problem. This problem occurs when the payoff of each person conflicts with the total payoff of the community which he/she belongs to. Evolutionary game theory has been used as a powerful mathematical framework to analyze such a social problem. Recently, the authors have proposed replicator dynamics with reallocation of payoffs. In this model, the government is willing to lead the population to a desirable goal state by using collections and reallocations of payoffs. In this paper, we investigate this model, and show conditions for the goal state to be a locally or a globally asymptotically stable equilibrium point, respectively. We also propose a government's strategy depends on population states which can stabilize the goal state globally.

  • An Image-Moment Sensor with Variable-Length Pipeline Structure

    Atsushi IWASHITA  Takashi KOMURO  Masatoshi ISHIKAWA  

     
    PAPER-Image Sensor/Vision Chip

      Vol:
    E90-C No:10
      Page(s):
    1876-1883

    A 128128 pixel functional image sensor was implemented. The sensor was able to capture images at 1,000 frame/s and extract the sizes and positions of 10 objects/frame when clocked at 8 MHz. The size of each pixel was 18 µm18 µm and the fill factor was 28%. The chip, 3.24 mm3.48 mm in size, was implemented with a 0.35 µm CMOS sensor process; the power consumption was 29.7 mW at 8 MHz.

  • A Voltage Scalable Advanced DFM RAM with Accelerated Screening for Low Power SoC Platform

    Hiroki SHIMANO  Fukashi MORISHITA  Katsumi DOSAKA  Kazutami ARIMOTO  

     
    PAPER-Next-Generation Memory for SoC

      Vol:
    E90-C No:10
      Page(s):
    1927-1935

    The advanced-DFM (Design For Manufacturability) RAM provides the solution for the limitation of SRAM voltage scaling down and the countermeasure of the process fluctuations. The characteristics of this RAM are the voltage scalability (@0.6 V operation) with wide operating margin and the reliability of long data retention time. The memory cell consists of 2 Cell/bit with the complementary dynamic memory operation and has the 1 Cell/bit test mode for the accelerated screening against the marginal cells. The GND bitline pre-charge sensing scheme and SSW (Sense Synchronized Write) peripheral circuit technologies are also adopted for the low voltage and DFV (Dynamic Frequency and Voltage) controllable SoC which will be strongly required from the many kinds of applications. This RAM supports the DFM functions with both good cell/bit for advanced process technologies and the voltage scalable SoC memory platform.

  • Modified Printed Folded λ/2 Dipole Antenna for DVB Applications

    Chia-Mei PENG  I-Fong CHEN  Ching-Wen HSUE  

     
    LETTER-Antennas and Propagation

      Vol:
    E90-B No:10
      Page(s):
    2991-2994

    In this letter, we present a modified printed folded λ/2 dipole antenna design for Digital Video Broadcasting (DVB) applications in UHF band (470-862 MHz). The arms of dipole are meandered to yield an asymmetrical structure. Wideband operation is obtained by increasing dipole-area. The impedance matching of the dipole structure is obtained by inserting some slots on the dipole-arms. This antenna combines omni-directional radiation pattern and wide bandwidth in an easy-to-fabricate structure. The experimental results of the constructed prototype are presented.

  • A Low Profile Folded Inverted-L Antenna for T-DMB/UHF Handset Application

    Seung Gil JEON  Won Sub KIM  Jae Hoon CHOI  

     
    LETTER-Antennas and Propagation

      Vol:
    E90-B No:10
      Page(s):
    2995-2998

    A novel low profile and dual-band antenna for terrestrial digital multimedia broadcasting (T-DMB) and ultra high frequency (UHF) applications is proposed in this paper. The proposed antenna consists of a folded inverted-L antenna and two open stubs. The designed low profile antenna occupies an antenna volume of 1484911 mm3. The length of the folded radiating element is about 0.09λ at the resonant frequency of T-DMB application (180-210 MHz). The parasitic open stubs are utilized to obtain the wide bandwidth (50%) for UHF application (470-740 MHz). The maximum gains at the frequencies of T-DMB and DTV applications were -5 and +5 dBi, respectively. The radiation patterns are near omni-directional at frequency of interest.

  • A Visual Inpainting Method Based on the Compressed Domain

    Yi-Wei JIANG  De XU  Moon-Ho LEE  Cong-Yan LANG  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E90-D No:10
      Page(s):
    1716-1719

    Visual inpainting is an interpolation problem that restores an image or a frame with missing or damaged parts. Over the past decades, a number of computable models of visual inpainting have been developed, but most of these models are based on the pixel domain. Little theoretical and computational work of visual inpainting is based on the compressed domain. In this paper, a visual inpainting model in the discrete cosine transform (DCT) domain is proposed. DCT coefficients of the non-inpainting blocks are utilized to get block features, and those block features are propagated to the inpainting region iteratively. The experimental results with I frames of MPEG4 are presented to demonstrate the efficiency and accuracy of the proposed algorithm.

  • Modeling and Simulation of ΔΣ Fractional-N PLL Frequency Synthesizer in Verilog-AMS

    Zhipeng YE  Wenbin CHEN  Michael Peter KENNEDY  

     
    PAPER-Nonlinear Circuits

      Vol:
    E90-A No:10
      Page(s):
    2141-2147

    A Verilog-AMS model of a fractional-N frequency synthesizer is presented that is capable of predicting spurious tones as well as noise and jitter performance. The model is based on a voltage-domain behavioral simulation. Simulation efficiency is improved by merging the voltage controlled oscillator (VCO) and the frequency divider. Due to the benefits of Verilog-AMS, the ΔΣ modulator which is incorporated in the synthesizer is modeled in a fully digital way. This makes it accurate enough to evaluate how the performance of the frequency synthesizer is affected by cyclic behavior in the ΔΣ modulator. The spur-minimizing effect of an odd initial condition on the first accumulator of the ΔΣ modulator is verified. Sequence length control and its effect on the fractional-N frequency synthesizer are also discussed. The simulated results are in agreement with prior published data on fractional-N synthesizers and with new measurement results.

  • Logic and Analog Test Schemes for a Single-Chip Pixel-Parallel Fingerprint Identification LSI

    Satoshi SHIGEMATSU  Hiroki MORIMURA  Toshishige SHIMAMURA  Takahiro HATANO  Namiko IKEDA  Yukio OKAZAKI  Katsuyuki MACHIDA  Mamoru NAKANISHI  

     
    PAPER-Image Sensor/Vision Chip

      Vol:
    E90-C No:10
      Page(s):
    1892-1899

    This paper describes logic and analog test schemes that improve the testability of a pixel-parallel fingerprint identification circuit. The pixel contains a processing circuit and a capacitive fingerprint sensor circuit. For the logic test, we propose a test method using a pseudo scan circuit to check the processing circuits of all pixels simultaneously. In the analog test, the sensor circuit employs dummy capacitance to mimic the state of a finger touching the chip. This enables an evaluation of the sensitivity of all sensor circuits on logical LSI tester without touching the chip with a finger. To check the effectiveness of the schemes, we applied them to a pixel array in a fingerprint identification LSI. The pseudo scan circuit achieved a 100% failure-detection rate for the processing circuit. The analog test determines that the sensitivities of the sensor circuit in all pixels are in the proper range. The results of the tests confirmed that the proposed schemes can completely detect defects in the circuits. Thus, the schemes will pave the way to logic and analog tests of chips integrating highly functional devices stacked on a LSI.

  • Fuzzy Tracker with Self-Tuning PID and Identifier Design Using Conditional-LMI and Improved Random Optimal Algorithm

    Zhi-Ren TSAI  Jiing-Dong HWANG  Yau-Zen CHANG  

     
    PAPER-Systems and Control

      Vol:
    E90-A No:10
      Page(s):
    2280-2289

    This study introduces the fuzzy Lyapunov function to the fuzzy PID control systems, modified fuzzy systems, with an optimized robust tracking performance. We propose a compound search strategy called conditional linear matrix inequality (CLMI) approach which was composed of the proposed improved random optimal algorithm (IROA) concatenated with the simplex method to solve the linear matrix inequality (LMI) problem. If solutions of a specific system exist, the scheme finds more than one solutions at a time, and these fixed potential solutions and variable PID gains are ready for tracking performance optimization. The effectiveness of the proposed control scheme is demonstrated by the numerical example of a cart-pole system.

  • An Inhibitory Neural-Network Circuit Exhibiting Noise Shaping with Subthreshold MOS Neuron Circuits

    Akira UTAGAWA  Tetsuya ASAI  Tetsuya HIROSE  Yoshihito AMEMIYA  

     
    PAPER-Neuron and Neural Networks

      Vol:
    E90-A No:10
      Page(s):
    2108-2115

    We designed subthreshold analog MOS circuits implementing an inhibitory network model that performs noise-shaping pulse-density modulation (PDM) with noisy neural elements, with the aim of developing a possible ultralow-power one-bit analog-to-digital converter. The static and dynamic noises given to the proposed circuits were obtained from device mismatches of current sources (transistors) and externally applied random spike currents, respectively. Through circuit simulations we confirmed that the circuit exhibited noise-shaping properties, and signal-to-noise ratio (SNR) of the network was improved by 7.9 dB compared with that of the uncoupled network as a result of noise shaping.

  • Basic Characteristics and Learning Potential of a Digital Spiking Neuron

    Hiroyuki TORIKAI  

     
    PAPER-Neuron and Neural Networks

      Vol:
    E90-A No:10
      Page(s):
    2093-2100

    The digital spiking neuron (DSN) consists of digital state cells and behaves like a simplified neuron model. By adjusting wirings among the cells, the DSN can generate spike-trains with various characteristics. In this paper we present a theorem that clarifies basic relations between change of wirings and change of characteristics of the spike-train. Also, in order to explore learning potential of the DSN, we propose a learning algorithm for generating spike-trains that are suited to an application example. We then show significances and basic roles of the presented theorem in the learning dynamics.

10321-10340hit(20498hit)