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[Keyword] EMP(607hit)

541-560hit(607hit)

  • On-Line Fault Diagnosis by Using Fuzzy Cognitive Map

    Keesang LEE  Sungho KIM  Masatoshi SAKAWA  

     
    PAPER-Reliability and Fault Analysis

      Vol:
    E79-A No:6
      Page(s):
    921-927

    A system based on application of Fuzzy Cognitive Map (FCM) to perform on-line fault diagnosis is presented. The diagnostic part of the system is composed of two diagnostic schemes. The first one (basic diagnostic algorithm) can be considered as a simple transition of Shiozaki's signed directed graph approach to FCM framework. The second one is an extended version of the basic diagnostic algorithm where an important concept, the temporal associative memories (TAM) recall of FCM, is adopted. In on-line application, self-generated fault FCM model generates predicted pattern sequence through the TAM recall process, which is compared with observed pattern sequence to declare the origin of fault. As the resultant diagnosis scheme takes short computation time, it can be used for on-line fault diagnosis of large and complex processes, and even for incipient fault diagnosis. In practical case, since real observed pattern sequence may be different from predicted one through the TAM recall owing to propagation delay between process variables, the time indexed fault FCM model incorporating delay time is proposed. The utility of the proposed system is illustrated in fault diagnosis of a tank-pipe system.

  • Automatic Hardware Synthesis of Multimedia Synchronizers from High-Level Specifications

    Kshirasagar NAIK  

     
    PAPER

      Vol:
    E79-D No:6
      Page(s):
    743-751

    In this paper, we show that by suitably selecting a notation to construct synchronization requirement specifications (SRS) for multimedia presentation we can express the timing characteristics at an abstract level, verify the specification, and obtain a hardware implementation through a sequence of transformations of the specification. First, we introduce the notion of a well-formed SRS and its hardware model. Second, we model an SRS as a timed Petri net and interpret the transitions of the net as hardware signals. To obtain logic functions from the SRS, we simplify the net and obtain a signal transition graph satisfying the unique state coding property. Finally, we show how to obtain a logic-level design of synchronizers.

  • Visualization of Temporal and Spatial Information in Natural Language Descriptions

    Hiromi BABA  Tsukasa NOMA  Naoyuki OKADA  

     
    PAPER-Image Processing,Computer Graphics and Pattern Recognition

      Vol:
    E79-D No:5
      Page(s):
    591-599

    This paper discusses visualization of temporal and spatial information in natural language descriptions (NLDs), focusing on the translation process of intermediate representations of NLDs to proper scenarios" and environments" for animations. First, the intermediate representations are shown according to the idea of actors. Actors and non-actors are represented as primitives of objects, whereas actions as those of events. Temporal and spatial constraints by a given NLD text are imposed upon the primitives. Then, the representations containing unknown temporal or spatial parameters --time and coordinates-- are translated into evaluation functions, where the unlikelihood of the deviations from the predicted temporal or spatial relations are estimated. Particularly, the functions concerning actor's movements contain both temporal and spatial parameters. Next, the sum of all the evaluation functions is minimized by a nonlinear optimization method. Thus, the most proper actors' time-table, or scenario, and non-actors' location-table, or environment, for visualization are obtained. Implementation and experiments show that both temporal and spatial information in NLDs are well connected through actors' movements for visualization.

  • Note Symbol Extraction for Printed Piano Scores Using Neural Networks*

    Hidetoshi MIYAO  Yasuaki NAKANO  

     
    PAPER-Document Recognition and Analysis

      Vol:
    E79-D No:5
      Page(s):
    548-554

    In the traditional note symbol extraction processes, extracted candidates of note elements were identified using complex if-then rules based on the note formation rules and they needed subtle adjustment of parameters through many experiments. The purpose of our system is to avoid the tedious tasks and to present an accurate and high-speed extraction of note heads, stems and flags according to the following procedure. (1) We extract head and flag candidates based on the stem positions. (2) To identify heads and flags from the candidates, we use a couple of three-layer neural networks. To make the networks learn, we give the position informations and reliability factors of candidates to the input units. (3) With the weights learned by the net, the head and flag candidates are recognized. As an experimental result, we obtained a high extraction rate of more than 99% for thirteen printed piano scores on A4 sheet which have various difficulties. Using a workstation (SPARC Station 10), it took about 90 seconds to do on the average. It means that our system can analyze piano scores 5 times or more as fast as the manual work. Therefore, our system can execute the task without the traditional tedious works, and can recognize them quickly and accurately.

  • Spatially and Temporally Joint Transmitter-Receiver Using an Adaptive Array Antenna

    Naoto ISHII  Ryuji KOHNO  

     
    PAPER-Modulation, Demodulation

      Vol:
    E79-B No:3
      Page(s):
    361-367

    Several papers have been shown equalization in the reception side. However, equalization in transmission side that is partial response signaling (PRS) or precoding is also possible in a two-way interactive communication such as time or frequency division duplex (TDD of FDD). This paper proposes and investigates a system which includes a transmission equalization and reception equalization based on an array antenna. This system is the extension in spatial and temporal domains. The channel capacity can be improved in the super channel which includes the transmitter and receiver array antenna.

  • Quantitative Evaluation of TMJ Sound by Frequency Analysis

    Hiroshi SHIGA  Yoshinori KOBAYASHI  

     
    LETTER

      Vol:
    E78-A No:12
      Page(s):
    1683-1688

    In order to evaluate quantitatively TMJ sound, TMJ sound in normal subject group, CMD patient group A with palpable sounds unknown to them, CMD patient group B with palpable sounds known to them, and CMD patient group C with audible sounds were detected by a contact microphone, and frequency analysis of the power spectra was performed. The power spectra of TMJ sound of normal subject group and patient group A showed patterns with frequency values below 100 Hz, whereas the power spectra of patient groups B and C showed distinctively different patterns with peaks of frequency component exceeding 100 Hz. As regards the cumulative frequency value, the patterns for each group clearly differed from those of other groups; in particular the 80% cumulative frequency value showed the greatest difference. From these results, it is assumed that the 80% cumulative frequency value can be used as an effective indicator for quantitative evaluation of TMJ sound.

  • Three-Level Broad-Edge Template Matching and Its Application to Real-Time Vision System

    Kazuhiko SUMI  Manabu HASHIMOTO  Haruhisa OKUDA  Shin'ichi KURODA  

     
    PAPER

      Vol:
    E78-D No:12
      Page(s):
    1526-1532

    This paper presents a new internal image representation, in which the scene is encoded into a three-intensity-level image. This representation is generated by Laplacian-Gaussian filtering followed by dual-thresholding. We refer to this imege as three-level broad-edge representation. It supresses the high frequency noise and shading in the image and encodes the sign of relative intensity of a pixel compared with surrounding region. Image model search based on cross correlation using this representation is as reliable as the one based on gray normalized correlation, while it reduces the computational cost by 50 times. We examined the reliability and realtime performance of this method when it is applied to an industrial object recognition task. Our prototype system achieves 3232 image model search from the 128128 pixel area in 2 milli-seconds with a 9 MHz pixel clock image processor. This speed is fast enough for searching and tracking a single object at video frame rate.

  • A Statically Typed, Temporal Object-Oriented Database Technology

    Suad ALAGI  

     
    PAPER-Model

      Vol:
    E78-D No:11
      Page(s):
    1469-1476

    A typed, object-oriented database technology, equipped with appropriate declarative, temporal logic based executable constraints, is presented. The underlying object-oriented database type system is based on advanced features such as subtype, parametric and F-bounded polymorphism. A particularly distinctive feature of the type system is its associated type-safe reflection technology, which provides the flexibility required by database operators without sacrificing type safety. Strongly, and even statically typed, executable class specifications of a variety of standard database abstractions, both application-oriented and system-oriented, are presented in the paper, in order to demonstrate strate the applicability of the paradigm. The temporal logic basis of the constraint language has an execution model, as well as the minimal model semantics, and it allows complex, temporal behavioral patterns to be expressed. It is based on three tomporal operators: always, next time and some time, and rules that determine how these operators may be applied in temporal Horn clauses. Because of the object-oriented nature of the paradigm, the logic basis is also equipped with the equality predicate The proposed technology is intended to provide major advantages not only in managing appropriately complex application environments with temporal constraints, but also in providing more efficient (because of static type checking) and reliable database management systems. It offers the advantages of non-procedural data languages and the richness of a temporal object-oriented paradigm. It also leads to a powerful prototyping tool for structural and behavioral testing of complex, strongly typed object-oriented systems, prior to major procedural implementation efforts.

  • An Object-Oriented Approach to Temporal Multimedia Data Modeling

    Yoshifumi MASUNAGA  

     
    PAPER-Model

      Vol:
    E78-D No:11
      Page(s):
    1477-1487

    This paper discusses an object-oriented approach to temporal multimedia data modeling in OMEGA; a multimedia database management under development at the University of Library and Information Science. An object-orientated approach is necessary to integrate various types of heterogeneous multimedia data, but it has become clear that current object-oriented data models are not sufficient to represent multimedia data, particularly when they are temporal. For instance, the current object-oriented data models cannot describe objects whose attribute values change time-dependently. Also, they cannot represent temporal relationships among temporal multimedia objects. We characterize temporal objects as instances of a subclass of class TimeInterval with the temporal attributes and the temporal relationships. This temporal multimedia data model is designed upward compatible with the ODMG-93 standard object model. To organize a temporal multimedia database, a five temporal axes model for representing temporal multimedia objects is also introduced. The five temporal axes--an absolute, an internal, a quasi-, a physical, and a presentation time axis--are necessary to describe time-dependent properties of multimedia objects in modeling, implementing and use. A concrete example of this organization method is also illustrated.

  • A Neural Net Classifier for Multi-Temporal LANDSAT TM Images

    Sei-ichiro KAMATA  Eiji KAWAGUCHI  

     
    PAPER-Image Processing, Computer Graphics and Pattern Recognition

      Vol:
    E78-D No:10
      Page(s):
    1295-1300

    The classification of remotely sensed multispectral data using classical statistical methods has been worked on for several decades. Recently there have been many new developments in neural network (NN) research, and many new applications have been studied. It is well known that NN approaches have the ability to classify without assuming a distribution. We have proposed an NN model to combine the spectral and spacial information of a LANDSAT TM image. In this paper, we apply the NN approach with a normalization method to classify multi-temporal LANDSAT TM images in order to investigate the robustness of our approach. From our experiments, we have confirmed that our approach is more effective for the classification of multi-temporal data than the original NN approach and maximum likelihood approach.

  • A 15-Gbit/s Si-Bipolar Gate Array

    Ryuusuke KAWANO  Minoru TOGASHI  Chikara YAMAGUCHI  Yoshiji KOBAYASHI  Masao SUZUKI  

     
    PAPER

      Vol:
    E78-C No:9
      Page(s):
    1203-1209

    We have developed a 15-Gbit/s 96-gate Si-bipolar gate array using 0.5-µm Si-bipolar technology, a sophisticated internal cell design, an I/O buffer design suitable for high-speed operation and high-frequency package technology. The decision circuit and 4 : 1 multiplexer fabricated on the gate array operate up to 15-Gbit/s and above 10-Gbit/s respectively. The data input sensitivity and the phase margin of the decision circuit are 53 mVpp and 288 at 10-Gbit/s operation. This gate array promises to be useful in shortening the development period and lowering cost of 10-Gbit/s class IC's.

  • Detection and Tracking of Facial Features by Using Edge Pixel Counting and Deformable Circular Template Matching

    Liyanage C. DE SILVA  Kiyoharu AIZAWA  Mitsutoshi HATORI  

     
    PAPER-Image Processing, Computer Graphics and Pattern Recognition

      Vol:
    E78-D No:9
      Page(s):
    1195-1207

    In this paper face feature detection and tracking are discussed, using methods called edge pixel counting and deformable circular template matching. Instead of utilizing color or gray scale information of the facial image, the proposed edge pixel counting method utilizes the edge information to estimate the face feature positions such as eyes, nose and mouth, using a variable size face feature template, the initial size of which is predetermined by using a facial image database. The method is robust in the sense that the detection is possible with facial images with different skin color and different facial orientations. Subsequently, by using a deformable circular template matching two iris positions of the face are determined and are used in the edge pixel counting, to track the features in the next frame. Although feature tracking using gray scale template matching often fails when inter frame correlation around the feature areas are very low due to facial expression change (such as, talking, smiling, eye blinking etc.), feature tracking using edge pixel counting can track facial features reliably. Some experimental results are shown to demonstrate the effectiveness of the proposed method.

  • Influence of Films' Thickness and Air Gaps in Surface Impedance Measurements of High Temperature Super-conductors Using the Dielectric Resonator Technique

    Janina CEREMUGA  Jerzy KRUPKA  Richard GEYER  Józef MODELSKI  

     
    PAPER

      Vol:
    E78-C No:8
      Page(s):
    1106-1110

    The dielectric resonator technique is commonly used for microwave surface resistance measurements of High Temperature superconducting (HTS) films. Thickness of super-conductors and its impact on measurement results has not been taken into consideration so far. A theoretical mode-matched solution analysis of a TE011 10 GHz sapphire resonator was performed. The results of this analysis demonstrate that the thickness of the films under test can significantly affect the resonant frequencies (fres) and quality factor Q of the resonant system, particularly when the thickness is less than three times the penetration depth (λ) of the films at the operating temperature. In such cases the microwave properties of the substrate affect fres and Q. For HTS films' thickness relatively small as compared to λ, measured quality factors and resonant frequency may also be affected by substrate thickness and the conductivity of the backing plates of the system. The presence of air gaps between the sapphire and the HTS films does not significantly influence surface resistance measurements. However they can markedly affect the surface reactance from which the penetration depth is calculated.

  • Spatial and Temporal Equalization Based on an Adaptive Tapped-Delay-Line Array Antenna

    Naoto ISHII  Ryuji KOHNO  

     
    PAPER

      Vol:
    E78-B No:8
      Page(s):
    1162-1169

    This paper describes a spatial and temporal multipath channel model which is useful in array antenna environments for mobile radio communications. From this model, a no distortion criterion, that is an extension of the Nyquist criterion, is derived for equalization in both spatial and temporal domains. An adaptive tapped-delay-line (TDL) array antenna is used as a tool for equalization in both spatial and temporal domains. Several criterion for such spatial and temporal equalization such as ZF (Zero Forcing) and MSE (Mean Square Error), are available to update the weights and tap coefficients. In this paper, we discuss the optimum weights based on the ZF criterion in both spatial and temporal domains. Since the ZF criterion satisfies the Nyquist criterion in case of noise free, this paper applies the ZF criterion for the spatial and temporal equalization as a simple case. The Z transform is applied to represent the spatial and temporal model of the multipath channel and to derive the optimal weights of the TDL array antenna. However, in some cases the optimal antenna weights cannot be decided uniquely. Therefore, the effect on the equalization errors due to a finite number of antenna elements and tap coefficients can be shown numerically by computer simulations.

  • Multifrequency Microwave Radiometry for Non-Invasive Thermometry Using a New Temperature Profile Model Function

    Hiroyuki OHBA  Masahiro KINOMURA  Michimasa ITO  Toshifumi SUGIURA  Shizuo MIZUSHINA  

     
    PAPER

      Vol:
    E78-C No:8
      Page(s):
    1071-1081

    Multifrequency microwave radiometry has been investigated for non-invasive measurement of temperatures in a human body. In this paper, we propose a new temperature profile model function, which is based on thermo-physiological considerations, for use in model fitting method of retrieving a temperature profile from a set of multifrequency radiometric data. The microwave radiometric technique using the new model function was tested by numerical simulations against animal experiment and clinical data reported elsewhere. The results show that the microwave radiometric technique can be used effectively to measure temperature profiles in tissues over a depth range from 0 to about 4.5 cm.

  • Temporal Verification of Real-Time Systems

    Sérgio V. CAMPOS  Edmund M. CLARKE  Wilfredo MARRERO  Marius MINEA  Hiromi HIRAISHI  

     
    PAPER

      Vol:
    E78-D No:7
      Page(s):
    796-801

    This paper presents a general method for computing quantitative information about finite-state real-time systems. We have developed algorithms that compute exact bounds on the delay between two specified events and on the number of occurrences of an event in a given interval. This technique allows us to determine performance measures such as schedulability, response time, and system load. Our algorithms produce more detailed information than traditional methods. This information leads to a better understanding of system behavior, in addition to determining its correctness. The algorithms presented in this paper are efficiently implemented using binary decision diagrams and have been incorporated into the SMV symbolic model checker. Using this method, we have verified a model of an aircraft control system with 1015 states. The results obtained demonstrate that our method can be successfully applied in the verification of real-time system designs.

  • Duration Modeling with Decreased Intra-Group Temporal Variation for HMM-Based Phoneme Recognition

    Nobuaki MINEMATSU  Keikichi HIROSE  

     
    PAPER

      Vol:
    E78-D No:6
      Page(s):
    654-661

    A new clustering method was proposed to increase the effect of duration modeling on the HMM-based phoneme recognition. A precise observation on the temporal correspondences between a phoneme HMM with output probabilities by single Gaussian modeling and its training data indicated that there were two extreme cases, one with several types of correspondences in a phoneme class completely different from each other, and the other with only one type of correspondence. Although duration modeling was commonly used to incorporate the temporal information in the HMMs, a good modeling could not be obtained for the former case. Further observation for phoneme HMMs with output probabilities by Gaussian mixture modeling also showed that some HMMs still had multiple temporal correspondences, though the number of such phonemes was reduced as compared to the case of single Gaussian modeling. An appropriate duration modeling cannot be obtained for these phoneme HMMs by the conventional methods, where the duration distribution for each HMM state is represented by a distribution function. In order to cope with the problem, a new method was proposed which was based on the clustering of phoneme classes with plural types of temporal correspondences into sub-classes. The clustering was conducted so as to reduce the variations of the temporal correspondences in sub-classes. After the clustering, an HMM was constructed for each sub-class. Using the proposed method, speaker dependent recognition experiments were performed for phonemes segmented from isolated words. A few-percent increase was realized in the recognition rate, which was not obtained by another method based on the duration modeling with a Gaussian mixture.

  • A Scheme for Word Detection in Continuous Speech Using Likelihood Scores of Segments Modified by Their Context Within a Word

    Sumio OHNO  Keikichi HIROSE  Hiroya FUJISAKI  

     
    PAPER

      Vol:
    E78-D No:6
      Page(s):
    725-731

    In conventional word-spotting methods for automatic recognition of continuous speech, individual frames or segments of the input speech are assigned labels and local likelihood scores solely on the basis of their own acoustic characteristics. On the other hand, experiments on human speech perception conducted by the present authors and others show that human perception of words in connected speech is based, not only on the acoustic characteristics of individual segments, but also on the acoustic and linguistic contexts in which these segments occurs. In other words, individual segments are not correctly perceive by humans unless they are accompanied by their context. These findings on the process of human speech perception have to be applied in automatic speech recognition in order to improve the performance. From this point of view, the present paper proposes a new scheme for detecting words in continuous speech based on template matching where the likelihood of each segment of a word is determined not only by its own characteristics but also by the likelihood of its context within the framework of a word. This is accomplished by modifying the likelihood score of each segment by the likelihood score of its phonetic context, the latter representing the degree of similarity of the context to that of a candidate word in the lexicon. Higher enhancement is given to the segmental likelihood score if the likelihood score of its context is higher. The advantage of the proposed scheme over conventional schemes is demonstrated by an experiment on constructing a word lattice using connected speech of Japanese uttered by a male speaker. The result indicates that the scheme is especially effective in giving correct recognition in cases where there are two or more candidate words which are almost equal in raw segmental likelihood scores.

  • Recent Trends in Medical Microwave Radiometry

    Shizuo MIZUSHINA  Hiroyuki OHBA  Katsumi ABE  Shinya MIZOSHIRI  Toshifumi SUGIURA  

     
    INVITED PAPER

      Vol:
    E78-B No:6
      Page(s):
    789-798

    Microwave radiometry has been investigated for non-invasive measurement of temperature in human body. Recent trends are to explore the capability of retrieving a temperature profile or map from a set of brightness temperatures measured by a multifrequency radiometer operating in a 1-6GHz range. The retrieval of temperature from the multifrequency measurement data is formulated as an inverse problem in which the number of independent measurement or data is limited (7) and the data suffer from considerably large random fluctuations. The standard deviation of the data fluctuation is given by the brightness temperature resolution of the instrument (0.04-0.1K). Solutions are prone to instabilities and large errors unless proper solution methods are used. Solution methods developed during the last few years are reviewed: singular system analysis, bio-heat transfer solution matched with radiometric data, and model-fitting combined with Monte Carlo technique. Typical results obtained by these methods are presented to indicate a crosssection of the present-state-of-the-development in the field. This review concludes with discussions on the radiometric weighting function which connects physical temperatures in object to the brightness temperature. Three-dimensional weighting functions derived by the modal analysis and the FDTD method for a rectangular waveguide antenna coupled to a four layered lossy medium are discussed. Development of temperature retrieval procedures incorporating the 3-D weighting functions is an important and challenging task for future work in this field.

  • Electromagnetic Near Fields of Rectangular Waveguide Antennas in Contact with Biological Objects Obtained by the FD-TD Method

    Katsumi ABE  Shinya MIZOSHIRI  Toshifumi SUGIURA  Shizuo MIZUSHINA  

     
    LETTER

      Vol:
    E78-B No:6
      Page(s):
    866-870

    Multifrequency microwave radiometry for non-invasive measurement of temperature in biological objects has been investigated in our laboratory. An open-ended rectangular waveguide filled with a dielectric has been used as a contact-type antenna of a radiometer operating over a 1-4GHz range. In the radiometric measurement, the radiometer measures the thermal radiation emitted by the object via the antenna as the brightness temperature. The brightness temperature is related to the physical temperatures in the object through the radiometric weighting function. By virtue of the reciprocity of antenna, the weighting function can be derived from the field distribution induced in the object by the same antenna when it is operated in the active mode. In this paper, the FD-TD method is used to analyze the problem of coupling between the rectangular waveguide antenna and a biological object. The objects studied in this paper are a homogeneous and a four-layered lossy media. Working frequency is 1.2GHz, which is the center frequency of the lowest-frequency band of our radiometer. Numerical results are presented in the form of SAR patterns. It is found that the SAR patterns tend to spread out in the lateral directions in the bolus, skin and fat layers due to the diffraction which becomes stronger at lower frequencies. Results also suggest that the lateral spreading can be controlled to a certain extent by choosing the size elf antenna flange properly.

541-560hit(607hit)