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[Keyword] CTI(8214hit)

3721-3740hit(8214hit)

  • Assigning Polarity to Causal Information in Financial Articles on Business Performance of Companies

    Hiroyuki SAKAI  Shigeru MASUYAMA  

     
    PAPER-Document Analysis

      Vol:
    E92-D No:12
      Page(s):
    2341-2350

    We propose a method of assigning polarity to causal information extracted from Japanese financial articles concerning business performance of companies. Our method assigns polarity (positive or negative) to causal information in accordance with business performance, e.g. "zidousya no uriage ga koutyou: (Sales of cars are good)" (The polarity positive is assigned in this example). We may use causal expressions assigned polarity by our method, e.g., to analyze content of articles concerning business performance circumstantially. First, our method classifies articles concerning business performance into positive articles and negative articles. Using them, our method assigns polarity (positive or negative) to causal information extracted from the set of articles concerning business performance. Although our method needs training dataset for classifying articles concerning business performance into positive and negative ones, our method does not need a training dataset for assigning polarity to causal information. Hence, even if causal information not appearing in the training dataset for classifying articles concerning business performance into positive and negative ones exist, our method is able to assign it polarity by using statistical information of this classified sets of articles. We evaluated our method and confirmed that it attained 74.4% precision and 50.4% recall of assigning polarity positive, and 76.8% precision and 61.5% recall of assigning polarity negative, respectively.

  • Boundary Implications for Stability Analysis of a Class of Uncertain Linear Time-Delay Systems by the Lambert W Function

    Hiroshi SHINOZAKI  Takehiro MORI  

     
    PAPER-Systems and Control

      Vol:
    E92-A No:12
      Page(s):
    3376-3380

    The purpose of the paper is to show that boundary implication results hold for complex-valued uncertain linear time-delay systems. The results are derived by the Lambert W function and yield tractable robust stability criteria for simultaneously triangularizable linear time-delay systems. The setting is similar to a recently reported extreme-point result, but the assumed uncertainty sets can be much more free in shape.

  • Comparison and Evaluation of Ship Detection and Identification Algorithms Using Small Boats and ALOS-PALSAR

    Seong-In HWANG  Haipeng WANG  Kazuo OUCHI  

     
    PAPER-Sensing

      Vol:
    E92-B No:12
      Page(s):
    3883-3892

    The final goal of the present project is to develop a ship detection and identification system by integrating spaceborne synthetic aperture radar (SAR), ground-based maritime radar and automatic identification system (AIS); and this article presents the results of the first phase experiments and current status toward achieving this goal. The data acquired by the Phased Array L-band SAR (PALSAR) on board of the Advanced Land Observing Satellite (ALOS) were used as SAR data, and X-band maritime radar including AIS were used as a ground-based system. The work is divided into two experimental phases. The first phase is to examine the ability of PALSAR to detect ships whose sizes are comparable with the SAR resolution cells, and the second is to incorporate the PALSAR data with those acquired by the ground-based radar with AIS. For the experiments in the first phase, we deployed three small fishing boats whose lengths ranged from approximately 8 m to 15 m in the Tosa Bay in Kochi, Japan in 2006. The experiments were carried out for four observation PALSAR modes: FBS (Fine Beam Single) 34.3, FBS 21.5, FBD (Fine Beam Double) 41.5, and PLR (PoLaRimetric) 20.5, where the numbers in each modes represent the off-nadir angles. For extracting the boats from the PALSAR images, five algorithms were considered, including amplitude-based, CFAR (Constant False Alarm Rate), MLCC (Multi-Look Cross-Correlation), CCF (Cross-Correlation Function) of HH- and HV-polarization amplitudes, and polarimetric analyses. This paper summarizes the results of the first phase experiments; the summary of the integrated system in the second phase will be reported in the near future.

  • Multicast Routing and Wavelength Assignment with Shared Protection in Multi-Fiber WDM Mesh Networks: Optimal and Heuristic Solutions

    Kampol WORADIT  Matthieu GUYOT  Pisit VANICHCHANUNT  Poompat SAENGUDOMLERT  Lunchakorn WUTTISITTIKULKIJ  

     
    PAPER-Fundamental Theories for Communications

      Vol:
    E92-B No:11
      Page(s):
    3401-3409

    While the problem of multicast routing and wavelength assignment (MC-RWA) in optical wavelength division multiplexing (WDM) networks has been investigated, relatively few researchers have considered network survivability for multicasting. This paper provides an optimization framework to solve the MC-RWA problem in a multi-fiber WDM network that can recover from a single-link failure with shared protection. Using the light-tree (LT) concept to support multicast sessions, we consider two protection strategies that try to reduce service disruptions after a link failure. The first strategy, called light-tree reconfiguration (LTR) protection, computes a new multicast LT for each session affected by the failure. The second strategy, called optical branch reconfiguration (OBR) protection, tries to restore a logical connection between two adjacent multicast members disconnected by the failure. To solve the MC-RWA problem optimally, we propose an integer linear programming (ILP) formulation that minimizes the total number of fibers required for both working and backup traffic. The ILP formulation takes into account joint routing of working and backup traffic, the wavelength continuity constraint, and the limited splitting degree of multicast-capable optical cross-connects (MC-OXCs). After showing some numerical results for optimal solutions, we propose heuristic algorithms that reduce the computational complexity and make the problem solvable for large networks. Numerical results suggest that the proposed heuristic yields efficient solutions compared to optimal solutions obtained from exact optimization.

  • Performance of Alamouti's OSTBC with Channel Estimation

    Shuichi OHNO  

     
    PAPER-Communication Theory and Systems

      Vol:
    E92-A No:11
      Page(s):
    2844-2850

    Alamouti's orthogonal space-time block code (OSTBC) is a simple yet important technique to take advantage of transmit diversity to mitigate fading channel effects. In this paper, we analyze the effects of time-selective channels and channel estimation errors on the bit error rate (BER) performance of Alamouti's OSTBC. We develop an analytical expression of the BER performance for the linear decoding with minimum mean squared error (MMSE) channel estimates in place of the true channel. Based on the expression, we derive a BER performance limit in decision-directed mode where the channel is tracked with Kalman filtering. Numerical examples are provided to validate our analysis and to see the impact of time-selective fading and channel estimation errors on the BER performance.

  • Energy-Efficient Pre-Execution Techniques in Two-Step Physical Register Deallocation

    Kazunaga HYODO  Kengo IWAMOTO  Hideki ANDO  

     
    PAPER-Computer Systems

      Vol:
    E92-D No:11
      Page(s):
    2186-2195

    Instruction pre-execution is an effective way to prefetch data. We previously proposed an instruction pre-execution scheme, which we call two-step physical register deallocation (TSD). The TSD realizes pre-execution by exploiting the difference between the amount of instruction-level parallelism available with an unlimited number of physical registers and that available with an actual number of physical registers. Although previous TSD study has successfully improved performance, it still has an inefficient energy consumption. This is because attempts are made for instructions to be pre-executed as much as possible, independently of whether or not they can significantly contribute to load latency reduction, allowing for maximal performance improvement. This paper presents a scheme that improves the energy efficiency of the TSD by pre-executing only those instructions that have great benefit. Our evaluation results using the SPECfp2000 benchmark show that our scheme reduces the dynamic pre-executed instruction count by 76%, compared with the original scheme. This reduction saves 7% energy consumption of the execution core with 2% overhead. Performance degrades by 2%, compared with that of the original scheme, but is still 15% higher than that of the normal processor without the TSD.

  • Comparison of Friction Characteristics on TN and VA Mode Alignment Films with Friction Force Microscopy Open Access

    Musun KWAK  Hanrok CHUNG  Hyukmin KWON  Jehyun KIM  Daekyung HAN  Yoonseon YI  Sangmun LEE  Chulgu LEE  Sooyoul CHA  

     
    INVITED PAPER

      Vol:
    E92-C No:11
      Page(s):
    1366-1370

    Using frictional force microscopy (FFM), the friction surface characteristics were compared between twisted nematic (TN) mode and vertical alignment (VA) mode alignment films (AFs). The friction asymmetry was detected depending on temperature conditions on TN mode AF, but not on VA mode AF. The difference between two modes was explained by leaning intermolecular repulsion caused by the pre-tilt angle uniformity and the density of side chain. No level difference according to temperature conditions appeared when the pre-tilt angle were measured after liquid crystal (LC) injection.

  • Error Probability of MRC in Frequency Selective Nakagami Fading in the Presence of CCI and ACI

    Mohammad Azizur RAHMAN  Chin-Sean SUM  Ryuhei FUNADA  Shigenobu SASAKI  Tuncer BAYKAS  Junyi WANG  Hiroshi HARADA  Shuzo KATO  

     
    PAPER

      Vol:
    E92-A No:11
      Page(s):
    2679-2687

    An exact expression of error rate is developed for maximal ratio combining (MRC) in an independent but not necessarily identically distributed frequency selective Nakagami fading channel taking into account inter-symbol, co-channel and adjacent channel interferences (ISI, CCI and ACI respectively). The characteristic function (CF) method is adopted. While accurate analysis of MRC performance cannot be seen in frequency selective channel taking ISI (and CCI) into account, such analysis for ACI has not been addressed yet. The general analysis presented in this paper solves a problem of past and present interest, which has so far been studied either approximately or in simulations. The exact method presented also lets us obtain an approximate error rate expression based on Gaussian approximation (GA) of the interferences. It is shown, especially while the channel is lightly faded, has fewer multipath components and a decaying delay profile, the GA may be substantially inaccurate at high signal-to-noise ratio. However, the exact results also reveal an important finding that there is a range of parameters where the simpler GA is reasonably accurate and hence, we don't have to go for more involved exact expression.

  • Effects of Annealing on Rubbed Polyimide Surface Studiedby Grazing-Incidence X-Ray Diffraction

    Ichiro HIROSAWA  Tomoyuki KOGANEZAWA  Hidenori ISHII  Takahiro SAKAI  

     
    PAPER

      Vol:
    E92-C No:11
      Page(s):
    1376-1381

    We investigated effect of annealing after rubbing by grazing incidence X-ray diffraction, since annealing process is performed in the actual process of liquid crystal display (LCD) fabrication. It was found that rubbed surface polymers were highly crystallized by annealing at 250 after rubbing, and that the crystallization of surface polymers by annealing occurred in the aligned polymer region induced by rubbing. Crystallization of surface polymers by annealing increasingly occurred as increasing of rubbing strength. Thus, it is considered that annealing process after rubbing should also play an important role to control liquid crystal alignment in LCD.

  • Characterization of Liquid Crystal Alignment on Rubbed Polyimide Film by Grazing-Incidence X-Ray Diffraction Open Access

    Tomoyuki KOGANEZAWA  Ichiro HIROSAWA  Hidenori ISHII  Takahiro SAKAI  

     
    INVITED PAPER

      Vol:
    E92-C No:11
      Page(s):
    1371-1375

    We developed a new method for characterizing molecular distribution in very thin liquid crystal layer (5-40 nm) evaporated onto rubbed polyimide film used by grazing-incidence X-ray diffraction (GIXD). The diffraction peaks corresponding to intermolecular correlation perpendicular to longitudinal axis of liquid crystal molecule and the clear anisotropic distribution of liquid crystal molecules in a thin layer were successfully observed. We found that in the vicinity of the alignment film, the intermolecular spacing correlation perpendicular to longitudinal axis of the 5CB molecule was expanded by the alignment film, and that the ordering of the 5CB was not so high. As the distance from the alignment film the spacing came close to the intrinsic intermolecular spacing.

  • Model Checking of Real-Time Properties of Resource-Bound Process Algebra

    Junkil PARK  Jungjae LEE  Jin-Young CHOI  Insup LEE  

     
    PAPER

      Vol:
    E92-A No:11
      Page(s):
    2781-2789

    The algebra of communicating shared resources (ACSR) is a timed process algebra which extends classical process algebras with the notion of a resource. In analyzing ACSR models, the existing techniques such as bisimulation checking and Hennessy-Milner Logic (HML) model checking are very important in theory of ACSR, but they are difficult to use for large complex system models in practice. In this paper, we suggest a framework to verify ACSR models against their requirements described in an expressive timed temporal logic. We demonstrate the usefulness of our approach with a real world case study.

  • Reading Technique of 2.45 GHz Band Small RFID Tags with an Adapter

    Peng WANG  Hiroyuki KOGA  Sho YAMADA  Shigeki OBOTE  Kenichi KAGOSHIMA  Kenji ARAKI  

     
    PAPER-Communication Theory and Systems

      Vol:
    E92-A No:11
      Page(s):
    2851-2857

    A 2.45-GHz-band small passive radio-frequency identification (RFID) tag consists of a small loop antenna and chip, and its size is several millimeters. Because of the tag's poor impedance-matching characteristic and radiation efficiency, an ordinary reader has difficulty reading it. We propose a new technique for reading the tag that involves installing a square half-wavelength meander-line conductor on the reader as an adapter and placing the adapter in the vicinity of the tag, and verify the effectiveness of the technique by simulation and experiment. Moreover, characteristics of simultaneous read of the small RFID tags by the proposed reading technique are revealed by simulation and experimental results.

  • 2D Log-Gabor Wavelet Based Action Recognition

    Ning LI  De XU  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E92-D No:11
      Page(s):
    2275-2278

    The frequency response of log-Gabor function matches well the frequency response of primate visual neurons. In this letter, motion-salient regions are extracted based on the 2D log-Gabor wavelet transform of the spatio-temporal form of actions. A supervised classification technique is then used to classify the actions. The proposed method is robust to the irregular segmentation of actors. Moreover, the 2D log-Gabor wavelet permits more compact representation of actions than the recent neurobiological models using Gabor wavelet.

  • Automatic Molar Extraction from Dental Panoramic Radiographs for Forensic Personal Identification

    Febriliyan SAMOPA  Akira ASANO  Akira TAGUCHI  

     
    LETTER-Biological Engineering

      Vol:
    E92-D No:11
      Page(s):
    2287-2290

    Measurement of an individual molar provides rich information for forensic personal identification. We propose a computer-based system for extracting an individual molar from dental panoramic radiographs. A molar is obtained by extracting the region-of-interest, separating the maxilla and mandible, and extracting the boundaries between teeth. The proposed system is almost fully automatic; all that the user has to do is clicking three points on the boundary between the maxilla and the mandible.

  • Performance Comparison between Two- and Three-Phase Coded Bi-directional Relaying Protocols

    Jung-Bin KIM  Dongwoo KIM  

     
    LETTER-Broadcast Systems

      Vol:
    E92-B No:11
      Page(s):
    3564-3567

    Recently proposed coded bi-directional relaying protocols increase the spectral efficiency by using network codes, which rely on joint packet encoding and exploitation of previously transmitted and stored information. In this letter, we derive the cumulative density function (CDF) and the probability density function (PDF) of received signal-to-noise ratios (SNRs) for two-phase and three-phase bi-directional coded relaying protocols, respectively, over Rayleigh fading channels. Using these results, we compare the outage performances as well as the average capacities of the protocols. From the numerical observations, we can see that the two-phase protocol has better link-level performances than the three-phase protocol when required data rate is greater than 2 for outate performance and transmit SNR at each node is greater than 18 dB for average capacity, respectively. Otherwise, the three-phase protocol performs better.

  • Basic Design of Video Communication System Enabling Usersto Move Around in Shared Space

    Keiji HIRATA  Yasunori HARADA  Toshihiro TAKADA  Naomi YAMASHITA  Shigemi AOYAGI  Yoshinari SHIRAI  Katsuhiko KAJI  Junji YAMATO  Kenji NAKAZAWA  

     
    PAPER

      Vol:
    E92-C No:11
      Page(s):
    1387-1395

    We propose a 2D display and camera arrangement for video communication systems that supports both spatial information between distant sites and user mobility. The implementation of this arrangement is called the "surrounding back screen method." The method enables users to freely come from and go into other users' spaces and provides every user with the direct pointing capability, since there is no apparent spatial barrier separating users, unlike the case of conventional video communication systems. In this paper, we introduce two properties ("sharedness" and "exclusiveness") and three parameters (a distance and two angles) to represent the geometrical relationship between two users. These properties and parameters are used to classify the shared spaces created by a video communication system and to investigate the surrounding back screen method. Furthermore, to demonstrate and explore our surrounding back screen method, we have developed a prototype system, called t-Room. Taking into account practical situations, we studied a practical case where two t-Rooms with different layouts are connected.

  • A Path Selection Technique Considering Time Difference of Arrival in Two-Hop Relay Systems

    Kyung-Soo WOO  Chang-Hwan PARK  Hyun-Il YOO  Jaekwon KIM  Seung-Hee HAN  Yong-Soo CHO  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E92-B No:11
      Page(s):
    3533-3536

    In this letter, the effect of the time difference of arrival (TDoA) on synchronous types or asynchronous types of OFDMA-based multi-hop relay (MR) systems is investigated. Signal-to-interference plus noise ratios (SINRs) for downlinks and uplinks are defined to measure the degree of interference due to TDoA in asymmetric MR systems. A path selection technique based on the SINR is then proposed to determine the optimal paths for the uplink and downlink independently. It is shown that asymmetric routing can improve the performance of OFDMA-based MR systems when the proposed technique is applied to the path selection of the uplink taking into account the effect of the TDoA.

  • A Hybrid Technique for Thickness-Map Visualization of the Hip Cartilages in MRI

    Mahdieh KHANMOHAMMADI  Reza AGHAIEZADEH ZOROOFI  Takashi NISHII  Hisashi TANAKA  Yoshinobu SATO  

     
    PAPER-Biological Engineering

      Vol:
    E92-D No:11
      Page(s):
    2253-2263

    Quantification of the hip cartilages is clinically important. In this study, we propose an automatic technique for segmentation and visualization of the acetabular and femoral head cartilages based on clinically obtained multi-slice T1-weighted MR data and a hybrid approach. We follow a knowledge based approach by employing several features such as the anatomical shapes of the hip femoral and acetabular cartilages and corresponding image intensities. We estimate the center of the femoral head by a Hough transform and then automatically select the volume of interest. We then automatically segment the hip bones by a self-adaptive vector quantization technique. Next, we localize the articular central line by a modified canny edge detector based on the first and second derivative filters along the radial lines originated from the femoral head center and anatomical constraint. We then roughly segment the acetabular and femoral head cartilages using derivative images obtained in the previous step and a top-hat filter. Final masks of the acetabular and femoral head cartilages are automatically performed by employing the rough results, the estimated articular center line and the anatomical knowledge. Next, we generate a thickness map for each cartilage in the radial direction based on a Euclidian distance. Three dimensional pelvic bones, acetabular and femoral cartilages and corresponding thicknesses are overlaid and visualized. The techniques have been implemented in C++ and MATLAB environment. We have evaluated and clarified the usefulness of the proposed techniques in the presence of 40 clinical hips multi-slice MR images.

  • Modeling the Saturation Effects for Narrowband Active Noise Control Systems

    Fu-Kun CHEN  Chih-Wei CHEN  

     
    LETTER-Digital Signal Processing

      Vol:
    E92-A No:11
      Page(s):
    2922-2926

    Based on the theoretical analysis of literature, saturation in measured signal of active noise control (ANC) systems will degrade the convergence speed. However, the experiments show that the saturated input signal can speed up the convergence of the narrow-band ANC systems. This paper intends to remodel the saturation effects for feedforward and feedback ANC systems. Combining the action of analog-to-digital converters (ADC), the mathematical expression and block diagrams are proposed to model the saturation effects in the practical ANC systems. The derivation and simulation results show that since the saturation is able to amplify the principle component of signal, the convergence would be speeded up.

  • Dynamic Load Balancing Method Based on Congestion Prediction for IP/LEO Satellite Networks

    Daigo KUDOH  Kenichi KASHIBUCHI  Hiroki NISHIYAMA  Nei KATO  

     
    PAPER

      Vol:
    E92-B No:11
      Page(s):
    3326-3334

    In Low Earth Orbit (LEO) satellite networks, the user distributions are unbalanced due to the geography and the population dispersion. As a result, some satellites have few traffic loads, while others have heavy traffic loads which often lead to congestion events. In this paper, we propose a novel load balancing method based on congestion prediction. In the proposed method, each satellite detects areas where congestion often occurs and conveys their positions to its adjacent satellites. In those areas, the concerned satellites perform load balancing algorithms to prevent congestion. The performance of the proposed method is evaluated through a number of simulations. The simulation results demonstrate that the proposed scheme improves packet drop rate, end-to-end delay, and throughput.

3721-3740hit(8214hit)