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[Keyword] POS(1110hit)

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  • Crystallization and Conductivity of ReO3 Thin Films Prepared by 90Off-Axis RF Magnetron Sputtering Method

    Nobuyuki IWATA  Kumiko FUKAI  Hiroshi YAMAMOTO  

     
    PAPER

      Vol:
    E87-C No:2
      Page(s):
    223-226

    We investigated growth conditions of the ReO3 thin films, as a first step of establishment of artificial superconducting multi-layer with the infinite layer cuprate and ReO3. The layers of ReO3 were expected to work as a charge reservoir block. The films were deposited from a Re metal target by off-axis reactive sputtering. Conductive and preferentially (100) oriented ReO3 thin films were obtained by in-situ post-annealing. The lowest resistivity was 4.4 10-5 ohmcm at room temperature.

  • Low Temperature Deposition of Indium Tin Oxide Thin Films by Low Voltage Sputtering in Various Rare Gases

    Yoichi HOSHI  Hidehiko SHIMIZU  

     
    PAPER

      Vol:
    E87-C No:2
      Page(s):
    212-217

    Indium tin oxide (ITO) films were deposited at a temperature below 50 by a low-voltage sputtering system. The sputtering voltage was fixed at 100 V and Ar, Kr, and Xe were used as the sputtering gases. Compared with the sputtering in Ar gas, the sputtering in Kr or Xe gas caused a significant suppression of crystallization of the deposited film and resulted in the formation of amorphous films. These films had much lower resistivities than the films deposited using Ar gas, since the Hall mobility of the films had a larger value. Typical Hall mobility and carrier density are 50 cm2/Vsec, and 51020 cm-3, respectively. This improvement was attributable to the reduction of high-energy particle bombardment to the film surface in the sputtering. These films are stable at a temperature below 150, and crystallization occurs at a temperature above 150.

  • Self-Nonself Recognition Algorithm Based on Positive and Negative Selection

    Kwee-Bo SIM  Dong-Wook LEE  

     
    LETTER-Applications of Information Security Techniques

      Vol:
    E87-D No:2
      Page(s):
    481-486

    In this paper, we propose a self-nonself recognition algorithm based on positive and negative selection used in the developing process of T cells. The anomaly detection algorithm based on negative selection is a representative model among self-recognition method and it has been applied to computer immune systems in recent years. In biological immune systems, T cells are produced through both positive and negative selection. Positive selection is the process used to determine a MHC receptor that recognizes self-molecules. Negative selection is the process used to determine an antigen receptor that recognizes antigens, or nonself cells. In this paper, we propose a self-recognition algorithm based on the positive selection and also propose a fusion algorithm based on both positive and negative selection. To verify the effectiveness of the proposed system, we show simulation results for detecting some infected data obtained from cell changes and string changes in the self-file.

  • A Self-Stabilizing Distributed Algorithm for the Steiner Tree Problem

    Sayaka KAMEI  Hirotsugu KAKUGAWA  

     
    PAPER

      Vol:
    E87-D No:2
      Page(s):
    299-307

    Self-stabilization is a theoretical framework of non-masking fault-tolerant distributed algorithms. In this paper, we investigate the Steiner tree problem in distributed systems, and propose a self-stabilizing heuristic solution to the problem. Our algorithm is constructed by four layered modules (sub-algorithms): construction of a shortest path forest, transformation of the network, construction of a minimum spanning tree, and pruning unnecessary links and processes. Competitiveness is 2(1-1/l), where l is the number of leaves of optimal solution.

  • Two Step POS Selection for SVM Based Text Categorization

    Takeshi MASUYAMA  Hiroshi NAKAGAWA  

     
    PAPER

      Vol:
    E87-D No:2
      Page(s):
    373-379

    Although many researchers have verified the superiority of Support Vector Machine (SVM) on text categorization tasks, some recent papers have reported much lower performance of SVM based text categorization methods when focusing on all types of parts of speech (POS) as input words and treating large numbers of training documents. This was caused by the overfitting problem that SVM sometimes selected unsuitable support vectors for each category in the training set. To avoid the overfitting problem, we propose a two step text categorization method with a variable cascaded feature selection (VCFS) using SVM. VCFS method selects a pair of the best number of words and the best POS combination for each category at each step of the cascade. We made use of the difference of words with the highest mutual information for each category on each POS combination. Through the experiments, we confirmed the validation of VCFS method compared with other SVM based text categorization methods, since our results showed that the macro-averaged F1 measure (64.8%) of VCFS method was significantly better than any reported F1 measures, though the micro-averaged F1 measure (85.4%) of VCFS method was similar to them.

  • Analog Circuit Design via Geometric Programming

    Maria del Mar HERSHENSON  

     
    INVITED PAPER

      Vol:
    E87-A No:2
      Page(s):
    298-310

    In this paper we describe a method for the automated design of analog circuits. The method simultaneously sizes the different components (transistors, capacitors, etc.) in a pre-defined circuit topology and places them according to a pre-defined slicing tree. The method is based on formulating the circuit physical and electrical behavior in a special convex form. More specifically, we cast the design problem as a geometric program, a special type of convex optimization problem. Therefore, all design constraints are formulated as posynomial inequality or monomial equality constraints. Very efficient numerical algorithms are then used to solve the resulting geometric program and to create the design that meets the desired specifications. The formulation is hierarchical and modular, allowing easy topology re-use and process porting. The synthesis method is fast, and determines the globally optimal design; in particular the final solution is completely independent of the starting point, and infeasible specifications are unambiguously detected. After a brief overview of current analog design automation solutions, we describe our method and provide some design examples for op-amps and analog-to-digital converters.

  • A Transformer between a Thin Post-Wall Waveguide and a Standard Metal Waveguide via a Dielectric Substrate Insertion with Slits Etched on It

    Takafumi KAI  Jiro HIROKAWA  Makoto ANDO  

     
    LETTER-Antennas and Propagation

      Vol:
    E87-B No:1
      Page(s):
    200-203

    This letter proposes a millimeter-wave band transformer to connect a standard waveguide to a very thin post-wall waveguide. The post-wall waveguide height is the same as a microstrip or coplanar line. A dielectric substrate with slits etched on both edges is inserted in the standard waveguide for matching. A 22 GHz transformer gives 3.6% bandwidth for a 0.5 mm-height post-wall waveguide. The effects of various mechanical misalignments upon the frequency characteristics of the reflection are also estimated by analysis and measurements.

  • Effect of Purge Time on the Properties of HfO2 Films Prepared by Atomic Layer Deposition

    Takaaki KAWAHARA  Kazuyoshi TORII  

     
    PAPER

      Vol:
    E87-C No:1
      Page(s):
    2-8

    The process mapping of the ALD process of HfO2 using HfCl4 and H2O is reported. A thickness uniformity better than 3% was achieved over a 300 mm-wafer at a deposition rate of 0.52 Å/cycle. Usually, H2O purge period is set less than 10 sec to obtain reasonable throughput; however, the amounts of residual impurities (Cl, H) found to be in the order of sub%, and these impurities are piled up near the HfO2/Si interface. In order to reduce the piled up impurities, we proposed a 2-step deposition in which purge period for initial 10-20 cycles was set to be 90 sec and that for remaining cycles was usual value of 7.5 sec. The leakage current is reduced to 1/10 by using this 2-step deposition.

  • Decomposition Approach of Banker's Algorithm: Design and Concurrency Analysis

    Hoon OH  

     
    PAPER-Software Systems

      Vol:
    E87-D No:1
      Page(s):
    183-195

    Concurrency in the computing systems using a deadlock avoidance strategy varies largely according to the way that resource usage plan of process is used in testing the possibility of deadlocks. If a detailed resource usage plan of process is to be taken into account, the deadlock avoidance problem is known to be NP-complete. A decomposition model to manage resources is proposed, where process is logically partitioned into a number of segments each of which uses at least one resource. It is shown that one of our deadlock avoidance algorithms achieves the best concurrency among the polynomial-bounded algorithms. We also present a heuristic algorithm that achieves concurrency close to the optimal one. Finally, we analyze concurrency of various algorithms.

  • Human Spine Posture Estimation from 2D Frontal and Lateral Views Using 3D Physically Accurate Spine Model

    Daisuke FURUKAWA  Kensaku MORI  Takayuki KITASAKA  Yasuhito SUENAGA  Kenji MASE  Tomoichi TAKAHASHI  

     
    PAPER-ME and Human Body

      Vol:
    E87-D No:1
      Page(s):
    146-154

    This paper proposes the design of a physically accurate spine model and its application to estimate three dimensional spine posture from the frontal and lateral views of a human body taken by two conventional video cameras. The accurate spine model proposed here is composed of rigid body parts approximating vertebral bodies and elastic body parts representing intervertebral disks. In the estimation process, we obtain neck and waist positions by fitting the Connected Vertebra Spheres Model to frontal and lateral silhouette images. Then the virtual forces acting on the top and the bottom vertebrae of the accurate spine model are computed based on the obtained neck and waist positions. The accurate model is deformed by the virtual forces, the gravitational force, and the forces of repulsion. The model thus deformed is regarded as the current posture. According to the preliminary experiments based on one real MR image data set of only one subject person, we confirmed that our proposed deformation method estimates the positions of the vertebrae within positional shifts of 3.2 6.8 mm. 3D posture of the spine could be estimated reasonably by applying the estimation method to actual human images taken by video cameras.

  • Constrained Location Algorithm Using TDOA Measurements

    Hing Cheung SO  Shun Ping HUI  

     
    LETTER-Digital Signal Processing

      Vol:
    E86-A No:12
      Page(s):
    3291-3293

    One conventional technique for source localization is to utilize the time-difference-of-arrival (TDOA) measurements of a signal received at spatially separated sensors. A simple TDOA-based location algorithm that combines the advantages of two efficient positioning methods is developed. It is demonstrated that the proposed approach can give optimum performance in geolocation via satellites at different noise conditions.

  • A Row-Parallel Position Detector for High-Speed 3-D Camera Based on Light-Section Method

    Yusuke OIKE  Makoto IKEDA  Kunihiro ASADA  

     
    PAPER-Electronic Circuits

      Vol:
    E86-C No:11
      Page(s):
    2320-2328

    A high-speed 3-D camera has a future possibility of wide variety of application fields such as quick inspection of industrial components, observation of motion/destruction of a target object, and fast collision prevention. In this paper, a row-parallel position detector for a high-speed 3-D camera based on a light-section method is presented. In our row-parallel search method, the positions of activated pixels are quickly detected by a row-parallel search circuit in pixel and a row-parallel address acquisition of O(log N) cycles in N-pixel horizontal resolution. The architecture keeps high-speed position detection in high pixel resolution. We have designed and fabricated the prototype position sensor with a 12816 pixel array in 0.35 µm CMOS process. The measurement results show it achieves quick activated-position acquisition of 450 ns for "beyond-real-time" 3-D imaging and visual feedback. The high-speed position detection of the scanning sheet beam is demonstrated.

  • A Design Method of an SPR System for Stabilization of a Crane without Velocity Measurement

    Young I. SON  Hyungbo SHIM  Kab-Il KIM  

     
    LETTER-Systems and Control

      Vol:
    E86-A No:11
      Page(s):
    2894-2896

    In order to stabilize a convey-crane with only cart position measurement, this paper designs an additional dynamics with which the parallel-connected system is feedback passive. Since the crane system can be stabilized with a proportional-derivative (PD) law, the additional system is constructed by using the PD gains, and the closed-loop system exhibits almost same performances with the PD law. With the proposed control law, the transfer function of the additional system has the form of sH(s) with a strictly positive real (SPR) H(s).

  • OC-48c High-Speed Network PCI Card: Implementation and Evaluation

    Kenji SHIMIZU  Tsuyoshi OGURA  Tetsuo KAWANO  Hiroyuki KIMIYAMA  Mitsuru MARUYAMA  

     
    PAPER

      Vol:
    E86-D No:11
      Page(s):
    2380-2389

    We have developed an OC-48c (2.4 Gbps) PCI-compliant network interface card and drivers with the aim of evaluating the effectiveness of our proposed link layer protocol MAPOS. In this paper, we study the effectiveness of MAPOS particularly from the viewpoint of the influence of packet sizes up to the 64-kbyte jumbo MTU size and the effectiveness of our new implementation of the non-interrupt-driven sending process and interrupt batching receiving process deployed to improve the throughput in short-packet transmissions. Our main findings are as follows; Enlarging the packet size up to 64-kbyte MTU improves the performance in transmission. OC-48c wire speed is achieved with packet sizes larger than 16 kbytes. Implementation of the non-interrupt-driven sending process and the interrupt batching receiving process improves the performance of short-packet transmission. In particular, the transmission throughput is improved by 50% when 64-byte short packets are used. The maximum loss-free receive rate is also raised by 50% when 4-kbyte packets arrive. With a high-performance CPU, the data-transfer speed of the DMA controller for jumbo packets cannot keep up with the packet-queueing speed of the CPU. Our proposed procedure for adaptive algorithm switching method can resolve this problem. The maximum TCP throughput observed in our measurement using the latest PCs and MAPOS OC-48c PCI card was 2342.5 Mbps. This throughput represents the highest performance in a legacy-PCI-based system according to the results database of the benchmarking software.

  • Normalizing Syntactic Structures Using Part-of-Speech Tags and Binary Rules

    Seongyong KIM  Kong-Joo LEE  Key-Sun CHOI  

     
    PAPER

      Vol:
    E86-D No:10
      Page(s):
    2049-2056

    We propose a normalization scheme of syntactic structures using a binary phrase structure grammar with composite labels. The normalization adopts binary rules so that the dependency between two sub-trees can be represented in the label of the tree. The label of a tree is composed of two attributes, each of which is extracted from each sub-tree, so that it can represent the compositional information of the tree. The composite label is generated from part-of-speech tags using an automatic labelling algorithm. Since the proposed normalization scheme is binary and uses only part-of-speech information, it can readily be used to compare the results of different syntactic analyses independently of their syntactic description and can be applied to other languages as well. It can also be used for syntactic analysis, which performs higher than the previous syntactic description for Korean corpus. We implement a tool that transforms a syntactic description into normalized one based on this proposed scheme. It can help construct a unified syntactic corpus and extract syntactic information from various types of syntactic corpus in a uniform way.

  • A New Modulation Technique Based on Pulse Position Modulation and Code Shift Keying

    Fumie ONO  Hiromasa HABUCHI  

     
    PAPER-Communication Systems

      Vol:
    E86-A No:10
      Page(s):
    2483-2491

    A Time Hopping Pulse Spacing Modulation (TH-PSM) system, which combines the pulse position modulation system with code shift keying, is proposed. The following performances are analyzed; (1) data transmission rate, (2) error rate in a single-user case, (3) error rate in a multi-user case, and (4) spectral efficiency. Consequently, the data transmission rate of the proposed system is higher than that of the conventional Spread Spectrum Pulse Position Modulation (SS-PPM) system. The proposed system can improve the probability of block error by increasing the number of information bits per spreading code. Moreover, the spectral efficiency of the proposed system is higher than that of the conventional system. The proposed system is more attractive than the conventional SS-PPM system for optical communications, power-line communications, and UWB communications.

  • Total Cost-Aware Proxy Caching with Cooperative Removal Policy

    Tian-Cheng HU  Yasushi IKEDA  Minoru NAKAZAWA  Shimmi HATTORI  

     
    PAPER-Network

      Vol:
    E86-B No:10
      Page(s):
    3050-3062

    Proxy caches have been used for a very long time to enhance the performance of web access. Along with the recent development of CDN (Content Distribution Network), the web proxy caching has also been adopted in many main techniques. This paper presents a new viewpoint on the possible improvement to the cooperative proxy caching, which can reduce outbound traffic and therefore ideally result in better response time. We take notice to the regional total cost of cache objects for optimizing content distribution. By contrast to the regular removal policies based on single proxy server, we prefer to evaluate a retrieved web object based on the metrics gathered from multiply proxy caches regionally. We particularly introduce a concept called post-removal analysis, which is used in measuring the value of the removed objects. Finally, we use the real proxy cache Squid to implement our proposal and modify the well-known cache benchmarking tool Web Polygraph to test this cooperative prototype. The test results prove that the proposed scheme can bring noticeable improvement on the performance of proxy caching.

  • In-Situ Technology for Evaluating the Stability of a Slider in 2 Dimensions

    Wei ZHANG  Bo LIU  

     
    PAPER

      Vol:
    E86-C No:9
      Page(s):
    1874-1878

    As head-disk spacing is reduced, the effects caused by inter-molecular level interactions between head-slider and disk media are becoming a severe stability concern of head-slider's positioning in both flying height and track following directions. Therefore, there is a need to explore simple but effective methods for characterizing two dimensional (2D) stability. Ideally methods should be easy to implement in both the laboratory and in the quality control of disk drive and component manufacturing. A reading process based in-situ method is explored in this work. The method is simple and can effectively reveal the 2D stability of the head-slider in both laboratory and manufacturing environments. The results obtained also suggest that the observable sway mode vibration of the suspension can be excited earlier than the air-bearing vibration mode, when the flying height is reduced.

  • A Multipurpose Image Watermarking Method for Copyright Notification and Protection

    Zhe-Ming LU  Hao-Tian WU  Dian-Guo XU  Sheng-He SUN  

     
    LETTER-Applications of Information Security Techniques

      Vol:
    E86-D No:9
      Page(s):
    1931-1933

    This paper presents an image watermarking method for two purposes: to notify the copyright owner with a visible watermark, and to protect the copyright with an invisible watermark. These two watermarks are embedded in different blocks with different methods. Simulation results show that the visible watermark is hard to remove and the invisible watermark is robust.

  • Balanced Bowtie Decomposition of Complete Multigraphs

    Kazuhiko USHIO  Hideaki FUJIMOTO  

     
    PAPER-Graphs and Networks

      Vol:
    E86-A No:9
      Page(s):
    2360-2365

    We show that the necessary and sufficient condition for the existence of a balanced bowtie decomposition of the complete multigraph λKn is n 5 and λ(n-1) 0 (mod 12). Decomposition algorithms are also given.

821-840hit(1110hit)