The search functionality is under construction.
The search functionality is under construction.

Keyword Search Result

[Keyword] TE(21534hit)

13381-13400hit(21534hit)

  • Improving Parsing Performance Using Corpus-Based Temporal Expression Analysis

    Juntae YOON  Seonho KIM  Hae-Chang RIM  

     
    LETTER-Natural Language Processing

      Vol:
    E87-D No:12
      Page(s):
    2898-2902

    This paper presents a method for improving the performance of syntactic analysis by using accurate temporal expression processing. Temporal expression causes parsing errors due to its syntactic duality, but its resolution is not trivial since the syntactic role of temporal expression is understandable in the context. In our work, syntactic functions of temporal words are decisively identified based on local contexts of individual temporal words acquired from a large corpus, which are represented by a finite state method. Experimental results show how the proposed method, incorporated with parsing, improves the accuracy and efficiency of the syntactic analysis.

  • A High Efficiency Adapter with Novel Current Driven Synchronous Rectifier

    Junming ZHANG  Xiaogao XIE  Dezhi JIAO  Zhaoming QIAN  

     
    PAPER-Power System Architecture

      Vol:
    E87-B No:12
      Page(s):
    3471-3477

    This paper presents a novel current driving method for the synchronous rectifier (SR) in a Flyback topology. Compared to the previous proposed Current Driven Synchronous Rectifier (CDSR), the proposed CDSR features simple structure, low power loss and good performance. The proposed SR driving method is implemented in a 64 W Flyback converter with universal input, and efficiency as high as 92.5% is achieved at low input (90 V ac) and full load condition.

  • A Selective Scan Chain Reconfiguration through Run-Length Coding for Test Data Compression and Scan Power Reduction

    Youhua SHI  Shinji KIMURA  Masao YANAGISAWA  Tatsuo OHTSUKI  

     
    PAPER-Test

      Vol:
    E87-A No:12
      Page(s):
    3208-3215

    Test data volume and power consumption for scan-based designs are two major concerns in system-on-a-chip testing. However, test set compaction by filling the don't-cares will invariably increase the scan-in power dissipation for scan testing, then the goals of test data reduction and low-power scan testing appear to be conflicted. Therefore, in this paper we present a selective scan chain reconfiguration method for test data compression and scan-in power reduction. The proposed method analyzes the compatibility of the internal scan cells for a given test set and then divides the scan cells into compatible classes. After the scan chain reconfiguration a dictionary is built to indicate the run-length of each compatible class and only the scan-in data for each class should be transferred from the ATE to the CUT so as to reduce test data volume. Experimental results for the larger ISCAS'89 benchmarks show that the proposed approach overcomes the limitations of traditional run-length coding techniques, and leads to highly reduced test data volume with significant power savings during scan testing in all cases.

  • User Preference Mining through Hybrid Collaborative Filtering and Content-Based Filtering in Recommendation System

    Kyung-Yong JUNG  Jung-Hyun LEE  

     
    PAPER-Artificial Intelligence and Cognitive Science

      Vol:
    E87-D No:12
      Page(s):
    2781-2790

    The growth of the Internet has resulted in an increasing need for personalized information systems. The paper describes an autonomous agent, the Web Robot Agent or WebBot, which integrates with the web and acts as a personal recommendation system that cooperates with the user in order to identify interesting pages. The Apriori algorithm extracts the characteristics of the web pages in the form of association words that are semantically related and mines a bag of association words. Using hybrid components from collaborative filtering and content-based filtering, this hybrid recommendation system can overcome the shortcomings associated with traditional recommendation systems. In this paper, we present an improved recommendation system, which uses the user preference mining through hybrid 2-way filtering. The proposed method was tested on a database, and its effectiveness compared with existent methods was proven in on-line experiments.

  • Hybrid Hierarchical Overlay Routing (Hyho): Towards Minimal Overlay Dilation

    Noriyuki TAKAHASHI  Jonathan M. SMITH  

     
    PAPER-Protocols, Applications and Services

      Vol:
    E87-D No:12
      Page(s):
    2586-2593

    Many P2P lookup services based on distributed hash tables (DHT) have appeared recently. These schemes are built upon overlay networks and ignore distance to the target resources. As a result, P2P lookups often suffer from unnecessarily long routes in the underlay network, which we call overlay dilation. This paper proposes a new scheme for resource routing, called hybrid hierarchical overlay routing, dubbed Hyho. We introduce distance-weighted Bloom filters (dwBFs) as a concise representation of routing information for scattered resources in overlay networks. To further reduce the size of Bloom filters, so that they are linear in the number of distinct resources, Hyho splits overlay networks in accordance with DHT, where each subnetwork has a smaller set of resources and spans the entire network thinly. As a result, Hyho constructs a hierarchical overlay network and routes requests accordingly. Simulation results show that Hyho can reduce overlay dilation to one half that yielded by the Chord lookup service.

  • Network of Plant Remote Monitoring System Using UDP/IP for Wind-Farms

    Haruhi ETO  Hirofumi MATSUO  Fujio KUROKAWA  

     
    PAPER-Power System Architecture

      Vol:
    E87-B No:12
      Page(s):
    3457-3464

    Wind power generation occupies an important position as a new non-fossil energy in recent years, and the plant scale has been rapidly expanding as wind-farm. Since they are often built in topographically inconvenient places, the remote monitoring system has been required. Ethernet had been said to be unsuitable to the industrial network, it is one of the strong options because of its low cost and easiness to apply. In this case, it is important to secure the throughput enough for updating the data of numerous wind turbines within a fixed time. In order to achieve this, we adopted User Datagram Protocol/Internet Protocol (UDP/IP) and the multi-thread method to make the overhead of software small as possible. This paper presents the scheme of powerful network using Ethernet with multi-thread and multi-cast. The relation between the number of threads and total throughputs of network is clarified. The design procedure to derive the optimum number of threads is shown. And it is demonstrated that this scheme provide the local network of wind-farm with sufficient performance.

  • Traffic Data Analysis Based on Extreme Value Theory and Its Applications to Predicting Unknown Serious Deterioration

    Masato UCHIDA  

     
    PAPER-Traffic Measurement and Analysis

      Vol:
    E87-D No:12
      Page(s):
    2654-2664

    It is important to predict serious deterioration of telecommunication quality. This paper investigates predicting such serious events by analyzing only a "short" period (i.e., a "small" amount) of teletraffic data. To achieve this end, this paper presents a method for analyzing the tail distributions of teletraffic state variables, because tail distributions are suitable for representing serious events. This method is based on Extreme Value Theory (EVT), which provides a firm theoretical foundation for the analysis. To be more precise, in this paper, we use throughput data measured on an actual network during daily busy hours for 15 minutes, and use its first 10 seconds (known data) to analyze the tail distribution. Then, we evaluate how well the obtained tail distribution can predict the tail distribution of the remaining 890 seconds (unknown data). The results indicate that the obtained tail distribution based on EVT by analyzing the small amount of known data can predict the tail distribution of unknown data much better than methods based on empirical or log-normal distributions. Furthermore, we apply the obtained tail distribution to predict the peak throughput in unknown data. The results of this paper enable us to predict serious deterioration events with lower measurement cost.

  • A High Time-Resolution Traffic Monitoring System

    Takahiro MUROOKA  Masashi HASHIMOTO  Toshiaki MIYAZAKI  

     
    PAPER-Traffic Measurement and Analysis

      Vol:
    E87-D No:12
      Page(s):
    2618-2626

    This innovative traffic-monitoring-system makes it possible to observe data-communication traffic on an oscilloscope-style display. It provides an efficient way of evaluating streaming-data quality. The monitoring system has a high time-resolution traffic value sampling function and a real-time data representation/recording mechanism that operate in synchrony. The user can directly evaluate the traffic shape with the monitoring system. In this paper, after describing the concept of the traffic monitoring system, we will describe a prototype built with programmable network equipment called A-BOX. We will then review a performance evaluation and other experimental results to prove that our monitoring system is suitable for video streaming.

  • Flexible Transmission Line Using High Permittivity LSE-NRD Guide at 60 GHz

    Futoshi KUROKI  Akira MIYAMAE  Tsukasa YONEYAMA  

     
    LETTER-Microwaves, Millimeter-Waves

      Vol:
    E87-C No:12
      Page(s):
    2195-2197

    A flexible transmission line, consisting of a thin ceramic-compounding Teflon strip, was devised by using a high permittivity LSE-NRD guide. This transmission line has the advantage of changeable shape. Low-loss performance was confirmed by measuring the transmission loss of the 180 degree bend and the S-shaped curve in the 60 GHz frequency band.

  • Theoretical Analysis of Relationships between Resonator Coupling Coefficient and Phase Noise in Microwave Negative-Resistance Oscillators

    Ken'ichi HOSOYA  Shin'ichi TANAKA  Kazuhiko HONJO  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E87-C No:12
      Page(s):
    2132-2142

    A new analytical approach which reveals relationships between resonator parameters (unloaded Q-factor, coupling coefficient, and loaded Q-factor) and phase noise in microwave negative-resistance oscillators is presented. On the basis of Kurokawa's theory, this approach derives analytical expressions for the phase noise as a function of the resonator parameters (with particular emphasis on the coupling coefficient). Two types of negative-resistance oscillators--classified according to the manner in which the resonator is used in a circuit--are analyzed. These analyses use realistic circuit configurations and design procedures. The passive network connecting the active device and the resonator, which is shown to have important effects on the above-mentioned relationship, is taken into account. Validity of the new approach is verified through harmonic-balance simulations. The presented analytical approach can provide useful guidelines for choosing the resonator parameters, especially the value of the coupling coefficient, when designing microwave negative-resistance oscillators.

  • Phonology and Morphology Modeling in a Very Large Vocabulary Hungarian Dictation System

    Mate SZARVAS  Sadaoki FURUI  

     
    PAPER-Speech and Hearing

      Vol:
    E87-D No:12
      Page(s):
    2791-2801

    This article introduces a novel approach to model phonology and morphosyntax in morpheme unit-based speech recognizers. The proposed methods are evaluated on a Hungarian newspaper dictation task that requires modeling over 1 million different word forms. The architecture of the recognition system is based on the weighted finite-state transducer (WFST) paradigm. The vocabulary units used in the system are morpheme-based in order to provide sufficient coverage of the large number of word-forms resulting from affixation and compounding. Besides the basic pronunciation model and the morpheme N-gram language model we evaluate a novel phonology model and the novel stochastic morphosyntactic language model (SMLM). Thanks to the flexible transducer-based architecture of the system, these new components are integrated seamlessly with the basic modules with no need to modify the decoder itself. We compare the phoneme, morpheme, and word error-rates as well as the sizes of the recognition networks in two configurations. In one configuration we use only the N-gram model while in the other we use the combined model. The proposed stochastic morphosyntactic language model decreases the morpheme error rate by between 1.7 and 7.2% relatively when compared to the baseline trigram system. The proposed phonology model reduced the error rate by 8.32%. The morpheme error-rate of the best configuration is 18% and the best word error-rate is 22.3%.

  • The Layered Receiver Employing Whitening Process for Multiple Space-Time Codes in Fast Flat Fading Channels

    Eun Jeong YIM  Dong Ku KIM  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E87-B No:12
      Page(s):
    3787-3790

    The multiple space-time trellis codes (M-STTC) structure is one of the Multiple Input Multiple output (MIMO) schemes providing high transmission rate and diversity and coding gain without bandwidth expansion. In this paper, an M-STTC system is proposed wherein the transmitter employs a multiple space-time TCM for the fast fading channel and the receiver has a decoding order block, several whitening processors, STTC decoders, and interference cancellers. The proposed layered receiver adopts a whitening process instead of a minimum mean squared error (MMSE) estimator, which is widely used in the BLAST type receiver. An optimum decoding order scheme is also planned since it gives at least a 2 dB gain in the proposed system in the fast flat Rayleigh fading channel of fd Tc = 1/3 at the FER of 10-2. For an M-STTC system employing two STTCs with four transmit and receive antennas, the layered receiver with whitening process obtains a 5 dB gain over the coded layered space-time processing in the fast flat Rayleigh fading channel at the FER of 10-2.

  • Stub Loaded Dual-Frequency Microstrip Antenna for 2 GHz and 5 GHz Use

    Shunsuke SAITO  Hiroyuki ARAI  

     
    PAPER-Antennas and Propagation

      Vol:
    E87-B No:12
      Page(s):
    3747-3752

    This paper presents a dual-frequency microstrip antenna for both 2 GHz and 5 GHz for a dual-band receiver. For a simple structure and low cost design, the microstrip feed circuit is designed on the same substrate as the antenna elements. Each antenna element is directly fed by the microstrip line, and the open stubs are loaded on the feed line of 2 GHz to suppress the higher order mode resonances between 2 GHz and 5 GHz. The feed line length of each antenna is adjusted so as to change it to the open condition at the other element frequency at the feed point. In addition, we propose the antenna structure in which two antenna elements for 2 GHz are split and placed at either sides of the 5 GHz antenna to coincide with the center positions of each antenna element. We investigate the proposed antenna by calculations and measurements to show the combiner free design for the dual band antenna.

  • Distributed QoS Control Based on Fairness of Quality for Video Streaming

    Kentaro OGAWA  Aki KOBAYASHI  Katsunori YAMAOKA  Yoshinori SAKAI  

     
    PAPER-Multimedia Systems for Communications" Multimedia Systems for Communications

      Vol:
    E87-B No:12
      Page(s):
    3766-3773

    In this paper, we propose an autonomously distributed QoS control method for MPEG video streaming in a wide area network. The capacity of the links and the characteristics of video streams change dynamically. However, managing the condition of all the links and streams in the network is difficult. In the proposed method, the routers in the network monitor the conditions of the links and streams locally and control the transmission rate of the stream server. Picture-quality oriented fairness is achieved by reducing the transmission rate of the streams with the higher PSNR in the bottleneck link. The computer simulation results show that the proposed method can be applied to a wide area network.

  • Progressive Coding of Binary Voxel Models Based on Pattern Code Representation

    Bong Gyun ROH  Chang-Su KIM  Sang-Uk LEE  

     
    PAPER-Digital Signal Processing

      Vol:
    E87-A No:12
      Page(s):
    3334-3342

    In this paper, we propose a progressive encoding algorithm for binary voxel models, which represent 3D object shapes. For progressive transmission, multi-resolution models are generated by decimating an input voxel model. Then, each resolution model is encoded by employing the pattern code representation(PCR). In PCR, the voxel model is represented with a series of pattern codes. The pattern of a voxel informs of the local shape of the model around that voxel. PCR can achieve a coding gain, since the pattern codes are highly correlated. In the multi-resolution framework, the coding gain can be further improved by exploiting the decimation constraints from the lower resolution models. Furthermore, the shell classification scheme is proposed to reduce the number of pattern codes to represent the whole voxel model. Simulation results show that the proposed algorithm provides about 1.1-1.3 times higher coding gain than the conventional PCR algorithm.

  • Abstraction and Optimization of Consistent Floorplanning with Pillar Block Constraints

    Ning FU  Shigetoshi NAKATAKE  Yasuhiro TAKASHIMA  Yoji KAJITANI  

     
    PAPER-Floorplan

      Vol:
    E87-A No:12
      Page(s):
    3224-3232

    The success in topdown design of recent huge system LSIs is in a seamless transfer of the information resulted from the high level design to the lower level of floorplanning. For the purpose, we introduce a new concept abstract floorplan which is included in the output of high level design. From the abstract floorplan, the pillar blocks are derived which are critical sets of blocks that are expected to determine the width and height of the chip, named the frame. Since the frame and pillar blocks are obtained in the high level stage, they are useful to keep the consistency in the low level physical design if we apply optimization regarding them as constraints. Experiments to MCNC benchmarks showed that abstract floorplanning by pillar blocks output a placement faithful to the one physically optimized block placement with respect to the chip area and the wire-length.

  • Experiment and Simulation of Step-Index Optical Fiber Temperature Sensor Using Two Modes

    Manabu YOSHIKAWA  Shouhei MASAGO  

     
    LETTER-Optoelectronics

      Vol:
    E87-C No:12
      Page(s):
    2193-2194

    Phase performance in a temperature sensor using a conventional single-mode step-index fiber is studied. Two modes are excited in a so called single-mode fiber when the wavelength of a laser source is shorter than the one suggested by the specification of a fiber. The phase shift due to the temperature change of a step-index fiber is analyzed. The intensity fluctuation by the interference of two modes is observed in the experiment and estimated in the computer simulation.

  • Dual-Mode Ring Bandpass Filter Using Defected Ground Structure with a Wider Stopband

    Ru Yuan YANG  Min Hung WENG  Hung Wei WU  Tsung Hui HUANG  Han-Ding HSUEH  Mau-Phon HOUNG  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E87-C No:12
      Page(s):
    2150-2157

    This paper proposes a novel dual-mode ring bandpass filter (BPF) using defect ground structure (DGS). The proposed filter provides wide stopband characteristic resulted from the bandgap characteristic of DGS for suppressing spurious response of the dual-mode ring BPF. The H shaped DGS cell is modeled as a parallel LC resonator and the equivalent circuit parameters are extracted. The relationship between bandgap characteristic and design parameters of DGS dimension is discussed and the bandgap characteristic of DGS on the filter performance is also investigated. The novel proposed filter has the frequency characteristics with a central frequency f0 = 7.7 GHz, a 3-dB bandwidth of 4.5% and wider stopband from 9 to 15.5 GHz at the level of -35 GHz. Measured results of experimental filter has good agreement with the theoretical simulation results.

  • Effect of Purge Gas on the Reliability of a 266 nm Continuous-Wave Solid-State Laser

    Hiroyuki WADA  Michio OKA  Koichi TATSUKI  Masaki SAITO  Shigeo KUBOTA  

     
    LETTER-Lasers, Quantum Electronics

      Vol:
    E87-C No:12
      Page(s):
    2186-2188

    The reliability of a 266 nm cw (continuous-wave) solid-state laser under the influence of purge gas was considered. Scatterers on a mirror during long-term operation were ammonium sulfate (NH4SO4). The synthesis of ammonium sulfate was related to the amount of water in the purge gas. UV power decreased by scatterers when the purge was not conducted.

  • An Embedded Processor Core for Consumer Appliances with 2.8GFLOPS and 36 M Polygons/s FPU

    Fumio ARAKAWA  Motokazu OZAWA  Osamu NISHII  Toshihiro HATTORI  Takeshi YOSHINAGA  Tomoichi HAYASHI  Yoshikazu KIYOSHIGE  Takashi OKADA  Masakazu NISHIBORI  Tomoyuki KODAMA  Tatsuya KAMEI  Makoto ISHIKAWA  

     
    PAPER-System Level Design

      Vol:
    E87-A No:12
      Page(s):
    3068-3074

    A SuperHTM embedded processor core implemented in a 130-nm CMOS process running at 400 MHz achieved 720 MIPS and 2.8 GFLOPS at a power of 250 mW in worst-case conditions. It has a dual-issue seven-stage pipeline architecture but maintains the 1.8 MIPS/MHz of the previous five-stage processor. The processor meets the requirements of a wide range of applications, and is suitable for digital appliances aimed at the consumer market, such as cellular phones, digital still/video cameras, and car navigation systems.

13381-13400hit(21534hit)