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[Keyword] REST(332hit)

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  • Selective Coding Scheme for Reconstructing an Interest Region with High Quality

    Jong-Bae LEE  Seong-Dae KIM  

     
    PAPER-Image Theory

      Vol:
    E81-A No:1
      Page(s):
    183-191

    In the circumstances we want to deal with, transmission channel is limited and global motion can happen by camera movement, and also there exists a region-of-interest (ROI) which is more important than background. So very low bit rate coding algorithm is required and processing of global motion must be considered. Also ROI must be reconstructed with required quality after decoding because of its importance. But the existing methods such as H. 261, H. 263 are not suitable for such situations because they do not compensate global motion, which needs large amount of transmission bits in motion information and degrades image quality. And also they can not reconstruct ROI's with high quality because they do not consider the fact that ROI's are more important than background. So a new coding scheme is proposed that describes a method for encoding image sequences distinguishing bits between ROI and background. Simulations show that the suggested algorithm performs well especially in the circumstances where background changes and the area of ROI is small enough compared with that of background.

  • Blind Deconvolution Based on Genetic Algorithms

    Yen-Wei CHEN  Zensho NAKAO  Kouichi ARAKAKI  Shinichi TAMURA  

     
    LETTER-Neural Networks

      Vol:
    E80-A No:12
      Page(s):
    2603-2607

    A genetic algorithm is presented for the blind-deconvolution problem of image restoration without any a priori information about object image or blurring function. The restoration problem is modeled as an optimization problem, whose cost function is to be minimized based on mechanics of natural selection and natural genetics. The applicability of GA for blind-deconvolution problem was demonstrated.

  • On Restoration of Overlapping Images

    Hideyuki IMAI  Yasuhisa NAKATA  Masaaki MIYAKOSHI  

     
    PAPER-Image Processing,Computer Graphics and Pattern Recognition

      Vol:
    E80-D No:12
      Page(s):
    1190-1194

    We consider the situation that plural degraded images are obtained. When no prior knowledge about original images are known, these images are individually restored by an optimum restoration filter, for example, by Wiener Filter or by Projection Filter. If correlations between original images are obtained, some restoration filters based on Wiener Filter or Projection Filter are proposed. In this paper, we deal with the case that some pixels or some parts of original images overlap, and propose a restoration method using a formulae for overlapping. The method is based on Partial Projection Filter. Moreover, we confirm an efficacy of the proposed method by numerical examples.

  • The Family of Parametric Projection Filters and Its Properties for Perturbation

    Hideyuki IMAI  Akira TANAKA  Masaaki MIYAKOSHI  

     
    PAPER-Image Processing,Computer Graphics and Pattern Recognition

      Vol:
    E80-D No:8
      Page(s):
    788-794

    A lot of optimum filters have been proposed for an image restoration problem. Parametric filter, such as Parametric Wiener Filter, Parametric Projection Filter, or Parametric Partial Projection Filter, is often used because it requires to calculate a generalized inverse of one operator. These optimum filters are formed by a degradation operator, a covariance operator of noise, and one of original images. In practice, these operators are estimated based on empirical knowledge. Unfortunately, it happens that such operators differ from the true ones. In this paper, we show the unified formulae of inducing them to clarify their common properties. Moreover, we investigate their properties for perturbation of a degradation operator, a covariance operator of noise, and one of original images. Some numerical examples follow to confirm that our description is valid.

  • Parameter Estimation and Restoration for Motion Blurred Images

    Qiang LI  Yasuo YOSHIDA  

     
    PAPER

      Vol:
    E80-A No:8
      Page(s):
    1430-1437

    The parameter estimation problem of point spread function is one of the most challenging and important task for image restoration. A new method for the parameter estimation in the case of motion blur is presented here. It is based on the principle that the power spectrum of the motion blurred image contains periodical minima relevant directly to the motion derection and length. Though the principle is very simple and effective in certain cases, the direct use of it may lead to poor performance an the signal-to-noise ratio (SNR) gets lower. To improve the estimation accuracy, by analyzing image noise effect on the detection of the minima, we propose a method to greatly reduce spectral noise, and give the lowest allowed SNR at which the minima may still be identified reliably. We also estimate the power spectrum of the original image, which is a must for the Wiener restoration filter, from the noisy blurred image based on a noncasual autoregressive model. Once above parameters are decided, the Wiener filter is used to restore the noisy blurred image. Our method is very practical; no parameter needs to be known a priori, or to be adjusted manually to fit into various application problems. The proposed method is finally applied to systhesized and real motion blurred images to demonstrate its effectiveness.

  • Histogram Matching by Moment Normalization

    Wen-Hao WANG  Yung-Chang CHEN  

     
    LETTER-Image Processing,Computer Graphics and Pattern Recognition

      Vol:
    E80-D No:7
      Page(s):
    746-750

    A moment-based method is proposed to estimate the illumination change between two images containing affinetransformed objects. The change is linearly modeled with parameters to be estimated by histograms due to its invariance of translation, rotation, and scaling. The parameters can be correctly estimated for an appropriate illumination change by normalizing the moments of the histograms.

  • Distributed-Controlled Multiple-Ring Networks with Classified Path Restoration

    Masahito TOMIZAWA  Shinji MATSUOKA  Yoshihiko UEMATSU  

     
    PAPER-Communication Networks and Services

      Vol:
    E80-B No:7
      Page(s):
    1000-1007

    This paper provides an architectural study of optical multiple-ring trunk-transmission networks using high-speed Time Division Multiplexing (TDM), and proposes two algorithms for distributed control environments. We propose a path-setup algorithm that uses Token protocol over Section Overhead (SOH) bytes, by which network-nodes communicate with each other to reserve bandwidth. A classified path restoration algorithm is also proposed that offers 3 path classes in terms of restoration performance. Class A paths, the most reliable, never lose any bit even against unpredictable disasters. They are realized by path-duplication at the source node, route diversity,and hitless switching at the destination node. Class B paths are restored by re-routing, where the original path-setup algorithm is reused. Class C paths are the most economical because a failed path is restored by maintenance action.

  • Fast Failure Restoration Algorithm with Reduced Messages Based on Flooding Mechanism

    Komwut WIPUSITWARAKUN  Hideki TODE  Hiromasa IKEDA  

     
    PAPER-Communication Networks and Services

      Vol:
    E80-B No:4
      Page(s):
    564-572

    A highly reliable network which can restore itself from network failures is one important concept for the future high capacity broadband network. In such self-healing network, flooding based failure-restoration algorithm is used to locate new routes and then to reroute failure traffic to that routes automatically when network failures such as link or node failures occur. Since the speed of this algorithm is degraded by the large amount of restoration messages produced by the process, such large volume messages should be reduced. In this paper, the scheme will be proposed, which reduces the large volume messages and efficiently selects alternative routes. In this scheme, the Message Wall will be used to filter useless restoration messages at the tandem nodes and Multi-Message Selecting method will be used to rapidly select a group of link-disjointed alternative routes from the feasible ones in each Flooding Wave sequence. The simulation results show that restoration messages are dramatically reduced and adequate alternative routes can be quickly found out.

  • Parallel Algorithms for Maximal Linear Forests

    Ryuhei UEHARA  Zhi-Zhong CHEN  

     
    PAPER

      Vol:
    E80-A No:4
      Page(s):
    627-634

    The maximal linear forest problem is to find, given a graph G = (V, E), a maximal subset of V that induces a linear forest. Three parallel algorithms for this problem are presented. The first one is randomized and runs in O(log n) expected time using n2 processors on a CRCW PRAM. The second one is deterministic and runs in O(log 2n) timeusing n4 processors on an EREW PRAM. The last one is deterministic and runs in O(log 5n) time using n3 processors on an EREW PRAM. The results put the problem in the class NC.

  • Optimization of Facility Planning and Circuit Routing for Survivable Transport NetworksAn Approach Based on Genetic Algorithm and Incremental Assignment

    Hajime NAKAMURA  Toshikane ODA  

     
    PAPER-Network planning techniques

      Vol:
    E80-B No:2
      Page(s):
    240-251

    This paper is concerned with two important planning problems for transport network planning; circuit routing problems and facility planning problems. We treated these optimization problems by taking into account survivability requirements. In the circuit routing problem tackled in this paper, therefore, optimization of circuit restoration plans, namely allocation of spare capacity for assumed failure scenarios is considered together with optimization of circuit routing in a no failure case. In the facility planning problems, failure scenarios of new facilities whose installation is yet to be determined are considered. In this paper, we present a formulation of these two optimization problems, and give 1) optimization algorithms based on the IA (Increment Assignment) method for routing problems and 2) optimization algorithms based on a combination of the GA (Genetic Algorithm) and the IA method for facility planning problems. The IA based routing algorithm can cope flexibly with various constraints on practical network operations and is applicable to large-scale complicated network models without causing a rapid increase in computation time. The GA based facility planning algorithm includes the IA based algorithm as a function for evaluating objective function values. Taking advantage of the important features of the IA based algorithm, we propose an acceleration technique for the GA based facility planning algorithm. In this paper, several numerical examples are provided and the effectiveness of the proposed algorithms is numerically evaluated.

  • Sorting on a2-D Multistage Architecture with Nearest-Neighbour Interconnection of Switches

    Josef GIGLMAYR  

     
    PAPER-Switching and Communication Processing

      Vol:
    E79-B No:12
      Page(s):
    1839-1851

    The polymer matrix for the number of N in-puts/outputs, N stages and 2x2-switches is denoted as the 1-D Spanke-Benes (SB) network. Throughout the paper, the 1-D SB-network, which equals the diamond cellular array, is extended to arbitrary dimensions by a mathematical transformation (a 1-D network provides the interconnection of 1-D data). This transformation determines the multistage architecture completely by providing size, location, geometry and wiring of the switches as well as it preserves properties of the networks, e.g., the capability of sorting. The SB-networks of dimension 3 are analysed and sorting is applied.

  • Some Properties of Deterministic Restricted One-Counter Automata

    Ken HIGUCHI  Mitsuo WAKATSUKI  Etsuji TOMITA  

     
    PAPER-Automata,Languages and Theory of Computing

      Vol:
    E79-D No:7
      Page(s):
    914-924

    A deterministic pushdown automaton (dpda) having just one stack symbol is called a deterministic restricted one-counter automaton (droca). A deterministic one-counter automaton (doca) is a dpda having only one stack symbol, with the exception of a bottom-of-stack market. The class of languages accepted by droca's is a proper subclass of the class of languages accepted by doca's. Valiant has shown that the regularity problem for doca's is decidable in a single exponential worst-case time complexity. In this paper, we prove that the class of languages accepted by droca's which accept by final state is incomparable with the class of languages accepted by droca's which accept by empty stack (strict droca's), and that the intersection of them is equal to the class of strict regular languages. In addition, we present a new direct branching algorithm for checking the regularity for not only a strict droca but also a real-time droca which accepts by final state. Then we show that the worst-case time complexity of our algorithm is polynomial in the size of each droca.

  • Image Restoration by Spatial Clustering

    Hiroto SHINGAI  Hiroyuki MATSUNAGA  Kiichi URAHAMA  

     
    LETTER-Image Processing,Computer Graphics and Pattern Recognition

      Vol:
    E79-D No:7
      Page(s):
    1000-1003

    A method based on clustering is presented for restoring and segmenting gray scale images. An optimum clustering obtained by a gradient method gives an image with gray scale values which vary smoothly in each segmented region. The method is also applied to restoration from sparsely sampled data.

  • Performance of Restricted Connective Semi-Random Network

    Shigeki SHIOKAWA  Iwao SASASE  

     
    PAPER-Communication Networks and Services

      Vol:
    E79-B No:6
      Page(s):
    826-835

    One of the important properties of multihop network is the mean internodal distance to evaluate the transmission delay, and the connective semi-random network achieves smaller mean internodal distance than other networks. However, the results are shown only by computer simulation and no theoretical analysis is investigated. Moreover, the network connective probability of the connective semi-random network is relatively small. In this paper, we propose the restricted connective semi-random network whose network connective probability is larger than that of the conventional connective semi-random network. And we theoretically analyze the mean internodal distance and the network connective probability of these two networks. It is shown that if the restriction is loose, the mean internodal distance of our model is almost the same as that of the conventional model, whereas the network connective probability of our model is larger than that of the conventional model. Moreover, the theoretical analyzed results of the mean internodal distance agree well with the simulated results in the conventional model and our model with small restriction.

  • Semiconductor Lightning Surge Protection Devices for Telecommunication Equipment

    Hidetaka SATOH  Yoshio SHIMODA  

     
    PAPER

      Vol:
    E79-B No:4
      Page(s):
    534-539

    Lightning surge protection semiconductor devices have been developed for subscriber telecommunication equipment that utilize transient thermal and low energy dissipation designs to improve surge-handling capability. A fabricated eight-cell device based on transient thermal design and a four-cell device with a thin substrate based on low energy dissipation design have a 1.83 and 1.80 times higher surge-handling capability, respectively, than a conventional device for lightning surge current waveforms of (1.5/30) µs.

  • Partially Supervised Learning for Nearest Neighbor Classifiers

    Hiroyuki MATSUNAGA  Kiichi URAHAMA  

     
    PAPER-Image Processing,Computer Graphics and Pattern Recognition

      Vol:
    E79-D No:2
      Page(s):
    130-135

    A learning algorithm is presented for nearest neighbor pattern classifiers for the cases where mixed supervised and unsupervised training data are given. The classification rule includes rejection of outlier patterns and fuzzy classification. This partially supervised learning problem is formulated as a multiobjective program which reduces to purely super-vised case when all training data are supervised or to the other extreme of fully unsupervised one when all data are unsupervised. The learning, i. e. the solution process of this program is performed with a gradient method for searching a saddle point of the Lagrange function of the program.

  • A Strategy for Forgetting Cases by Restricting Memory

    Hiroyoshi WATANABE  Kenzo OKUDA  Shozo FUJIWARA  

     
    LETTER-Artificial Intelligence and Cognitive Science

      Vol:
    E78-D No:10
      Page(s):
    1324-1326

    We present basic strategies for memory-restricted forgetting mechanisms of cases and propose a forgetting strategy which is a combination of the basic strategies. The effectivness of the proposed strategy for improving the performance of case-based reasoning systems is demonstrated through simulations in the electric power systems.

  • A Polynomial-Time Algorithm for Checking the Inclusion for Real-Time Deterministic Restricted One-Counter Automata Which Accept by Final State

    Ken HIGUCHI  Mitsuo WAKATSUKI  Etsuji TOMITA  

     
    PAPER-Automata, Languages and Theory of Computing

      Vol:
    E78-D No:8
      Page(s):
    939-950

    A deterministic pushdown automaton (dpda) having just one stack symbol is called a deterministic restricted one-counter automaton (droca). A deterministic one-counter automaton (doca) is a dpda having only one stack symbol, with the exception of a bottom-of-stack marker. The class of languages accepted by droca's which accept by final state is a proper subclass of the class of languages accepted by doca's. Valiant has proved the decidability of the equivalence problem for doca's and the undecidability of the inclusion problem for doca's. Hence the decidability of the equivalence problem for droca's is obvious. In this paper, we evaluate the upper bound of the length of the shortest input string (witness) that disproves the inclusion for a pair of real-time droca's which accept by final state, and present a new direct branching algorithm for checking the inclusion for a pair of languages accepted by these droca's. Then we show that the worst-case time complexity of our algorithm is polynomial in the size of these droca's.

  • Network Restoration Algorithm for Multimedia Communication Services and Its Performance Characteristics

    Mitsuhiro AZUMA  Yasuki FUJII  Yasuyuki SATO  Takafumi CHUJO  Koso MURAKAMI  

     
    PAPER

      Vol:
    E78-B No:7
      Page(s):
    987-994

    Multimedia communication services are being made available with the advent of broadband optical fiber networks. As many different services will be accommodated in such networks, network survivability has been recognized to be a crucial concern. In this paper, we propose a new restoration algorithm for ATM networks providing multimedia services. Our proposed restoration algorithm adopts the message bundling scheme of the Multi-Destination Flooding (MDF) algorithm which was previously proposed for STM-based networks to handle catastrophic failures such as multiple link and node failures. Virtual Paths (VP) with the same communication speed are bundled and Operation Administration and Maintenance (OAM) cells are used for communication of restoration messages. In addition, the following modifications are made on the original MDF to improve restoration performance. The pre-cancellation scheme is adopted to arbitrate reservation contention to realize high restoration ratio. The dual queue scheme is applied to avoid congestion of restoration messages. Moreover, the connection control scheme for VPI connections is proposed to prevent alternative routes from being misconnected. This paper describes the design concept of our restoration algorithm, processes in each restoration phase, and the performance evaluation by computer simulation.

  • A Synthesis of a Forest-Type Optimal File Transfer on a File Transmission Net with Source Vertices

    Yoshihiro KANEKO  Koichi SUZUKI  Shoji SHINODA  Kazuo HORIUCHI  

     
    PAPER

      Vol:
    E78-A No:6
      Page(s):
    671-679

    A problem of synthesizing an optimal file transfer on a file transmission net N is to consider how to distribute, with a minimum total cost, copies of a file J with some information from source vertex set S to all vertices of N by the respective vertices' copy demand numbers. The case of |S| =1 has been studied so far. This paper deals with N such that |S|1, where a forest-type file transfer is defined. This paper proposes a polynomial time algorithm to synthesize an optimal forest-type file transfer on such N satisfying SM U, where M and U are mother vertex set and positive demand vertex set of N, respectively.

301-320hit(332hit)