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[Keyword] OMP(3945hit)

1701-1720hit(3945hit)

  • Novel Fiber Jacket Removing System by a CO2 Laser for Compact Packaging of Optical Components

    Keisuke IKUSHIMA  Ryou SOUGEN  Osanori KOYAMA  Makoto YAMADA  Yutaka KATSUYAMA  

     
    LETTER-Optical Fiber for Communications

      Vol:
    E93-B No:1
      Page(s):
    158-161

    A novel fiber jacket removing system by a CO2 laser has been proposed to realize compact packaging of optical components. It has been clarified experimentally that excess-fiber-free MT connectorization is possible for 4-fiber ribbon.

  • Reduction of Test Data Volume and Improvement of Diagnosability Using Hybrid Compression

    Anis UZZAMAN  Brion KELLER  Brian FOUTZ  Sandeep BHATIA  Thomas BARTENSTEIN  Masayuki ARAI  Kazuhiko IWASAKI  

     
    PAPER

      Vol:
    E93-D No:1
      Page(s):
    17-23

    This paper describes a simple means to enable direct diagnosis by bypassing MISRs on a small set of tests (MISR-bypass test mode) while achieving ultimate output compression using MISRs for the majority of tests (MISR-enabled test mode.) By combining two compression schemes, XOR and MISRs in the same device, it becomes possible to have high compression and still support compression mode volume diagnostics. In our experiment, the MISR-bypass test was first executed and at 10% of the total test set the MISR-enabled test was performed. The results show that compared with MISR+XOR-based compression the proposed technique provides better volume diagnosis with slightly small (0.71 X to 0.97 X) compaction ratio. The scan cycles are about the same as the MISR-enabled mode. A possible application to partial good chips is also shown.

  • Activating Humans with Humor -- A Dialogue System That Users Want to Interact with

    Pawel DYBALA  Michal PTASZYNSKI  Rafal RZEPKA  Kenji ARAKI  

     
    PAPER-Spoken Dialogue System

      Vol:
    E92-D No:12
      Page(s):
    2394-2401

    The topic of Human Computer Interaction (HCI) has been gathering more and more scientific attention of late. A very important, but often undervalued area in this field is human engagement. That is, a person's commitment to take part in and continue the interaction. In this paper we describe work on a humor-equipped casual conversational system (chatterbot) and investigate the effect of humor on a user's engagement in the conversation. A group of users was made to converse with two systems: one with and one without humor. The chat logs were then analyzed using an emotive analysis system to check user reactions and attitudes towards each system. Results were projected on Russell 's two-dimensional emotiveness space to evaluate the positivity/negativity and activation/deactivation of these emotions. This analysis indicated emotions elicited by the humor-equipped system were more positively active and less negatively active than by the system without humor. The implications of results and relation between them and user engagement in the conversation are discussed. We also propose a distinction between positive and negative engagement.

  • Evaluation of Effective Conductivity of Copper-Clad Dielectric Laminate Substrates in Millimeter-Wave Bands Using Whispering Gallery Mode Resonators

    Thi Huong TRAN  Yuanfeng SHE  Jiro HIROKAWA  Kimio SAKURAI  Yoshinori KOGAMI  Makoto ANDO  

     
    PAPER-Electronic Materials

      Vol:
    E92-C No:12
      Page(s):
    1504-1511

    This paper presents a measurement method for determining effective conductivity of copper-clad dielectric laminate substrates in the millimeter-wave region. The conductivity is indirectly evaluated from measured resonant frequencies and unloaded Q values of a number of Whispering Gallery modes excited in a circular disk sample, which consists of a copper-clad dielectric substrate with a large diameter of 20-30 wavelengths. We can, therefore, obtain easily the frequency dependence of the effective conductivity of the sample under test in a wide range of frequency at once. Almost identical conductivity is predicted for two kinds of WG resonators (the copper-clad type and the sandwich type) with different field distribution; it is self-consistent and provides the important foundation for the method if not for the alternative method at this moment. We measure three kinds of copper foils in 55-65 GHz band, where the conductivity of electrodeposited copper foil is smaller than that of rolled copper foil and shiny-both-sides copper foil. The measured conductivity for the electrodeposited copper foil decreases with an increase in the frequency. The transmission losses measured for microstrip lines which are fabricated from these substrates are accurately predicted with the conductivity evaluated by this method.

  • Low-Voltage Process-Compensated VCO with On-Chip Process Monitoring and Body-Biasing Circuit Techniques

    Ken UENO  Tetsuya HIROSE  Tetsuya ASAI  Yoshihito AMEMIYA  

     
    LETTER-Device and Circuit Modeling and Analysis

      Vol:
    E92-A No:12
      Page(s):
    3079-3081

    A voltage-controlled oscillator (VCO) tolerant to process variations at lower supply voltage was proposed. The circuit consists of an on-chip threshold-voltage-monitoring circuit, a current-source circuit, a body- biasing control circuit, and the delay cells of the VCO. Because variations in low-voltage VCO frequency are mainly determined by that of the current in delay cells, a current-compensation technique was adopted by using an on-chip threshold-voltage-monitoring circuit and body-biasing circuit techniques. Monte Carlo SPICE simulations demonstrated that variations in the oscillation frequency by using the proposed techniques were able to be suppressed about 65% at a 1-V supply voltage, compared to frequencies with and without the techniques.

  • Influence of PH3 Preflow Time on Initial Growth of GaP on Si Substrates by Metalorganic Vapor Phase Epitaxy

    Yasushi TAKANO  Takuya OKAMOTO  Tatsuya TAKAGI  Shunro FUKE  

     
    PAPER-Nanomaterials and Nanostructures

      Vol:
    E92-C No:12
      Page(s):
    1443-1448

    Initial growth of GaP on Si substrates using metalorganic vapor phase epitaxy was studied. Si substrates were exposed to PH3 preflow for 15 s or 120 s at 830 after they were preheated at 925. Atomic force microscopy (AFM) revealed that the Si surface after preflow for 120 s was much rougher than that after preflow for 15 s. After 1.5 nm GaP deposition on the Si substrates at 830, GaP islands nucleated more uniformly on the Si substrate after preflow for 15 s than on the substrate after preflow for 120 s. After 3 nm GaP deposition, layer structures were observed on a fraction of Si surface after preflow for 15 s. Island-like structures remained on the Si surface after preflow for 120 s. After 6 nm GaP deposition, the continuity of GaP layers improved on both substrates. However, AFM shows pits that penetrated a Si substrate with preflow for 120 s. Transmission electron microscopy of a GaP layer on the Si substrate after preflow for 120 s revealed that V-shaped pits penetrated the Si substrate. The preflow for a long time roughened the Si surface, which facilitated the pit formation during GaP growth in addition to degrading the surface morphology of GaP at the initial growth stage. Even after 50 nm GaP deposition, pits with a density on the order of 107 cm-2 remained in the sample. A 50-nm-thick flat GaP surface without pits was achieved for the sample with PH3 preflow for 15 s. The PH3 short preflow is necessary to produce a flat GaP surface on a Si substrate.

  • Burst Error Recovery Method for LZSS Coding

    Masato KITAKAMI  Teruki KAWASAKI  

     
    PAPER-Dependable Computing

      Vol:
    E92-D No:12
      Page(s):
    2439-2444

    Since the compressed data, which are frequently used in computer systems and communication systems, are very sensitive to errors, several error recovery methods for data compression have been proposed. Error recovery method for LZ77 coding, one of the most popular universal data compression methods, has been proposed. This cannot be applied to LZSS coding, a variation of LZ77 coding, because its compressed data consist of variable-length codewords. This paper proposes a burst error recovery method for LZSS coding. The error sensitive part of the compressed data are encoded by unary coding and moved to the beginning of the compressed data. After these data, a synchronization sequence is inserted. By searching the synchronization sequence, errors in the error sensitive part are detected. The errors are recovered by using a copy of the part. Computer simulation says that the compression ratio of the proposed method is almost equal to that of LZ77 coding and that it has very high error recovery capability.

  • A Study of Inherent Pen Input Modalities for Precision Parameter Manipulations during Trajectory Tasks

    Yizhong XIN  Xiangshi REN  

     
    PAPER-Human-computer Interaction

      Vol:
    E92-D No:12
      Page(s):
    2454-2461

    Adjustment of a certain parameter in the course of performing a trajectory task such as drawing or gesturing is a common manipulation in pen-based interaction. Since pen tip information is confined to x-y coordinate data, such concurrent parameter adjustment is not easily accomplished in devices using only a pen tip. This paper comparatively investigates the performance of inherent pen input modalities (Pressure, Tilt, Azimuth, and Rolling) and Key Pressing with the non-preferred hand used for precision parameter manipulation during pen sliding actions. We elaborate our experimental design framework here and conduct experimentation to evaluate the effect of the five techniques. Results show that Pressure enabled the fastest performance along with the lowest error rate, while Azimuth exhibited the worst performance. Tilt showed slightly faster performance and achieved a lower error rate than Rolling. However, Rolling achieved the most significant learning effect on Selection Time and was favored over Tilt in subjective evaluations. Our experimental results afford a general understanding of the performance of inherent pen input modalities in the course of a trajectory task in HCI (human computer interaction).

  • CrossOverlayDesktop: Dynamic Overlay of Desktop Graphics between Co-located Computers for Multi-User Interaction

    Daisuke IWAI  Kosuke SATO  

     
    PAPER-Human-computer Interaction

      Vol:
    E92-D No:12
      Page(s):
    2445-2453

    This paper presents an intuitive interaction technique for data exchange between multiple co-located devices. In the proposed system, CrossOverlayDesktop, desktop graphics of the devices are graphically overlaid with each other (i.e., alpha-blended). Users can exchange file data by the usual drag-and-drop manipulation through an overlaid area. The overlaid area is determined by the physical six degrees of freedom (6-DOF) correlation of the devices and thus changes according to users' direct movements of the devices. Because familiar operations such as drag-and-drop can be applied to file exchange between multiple devices, seamless, consistent, and thus intuitive multi-user collaboration is realized. Furthermore, dynamic overlay of desktop graphics allows users to intuitively establish communication, identify connected devices, and perform access control. For access control of the data, users can protect their own data by simply dragging them out of the overlaid area, because only the overlaid area becomes a public space. Several proof-of-concept experiments and evaluations were conducted. Results show the effectiveness of the proposed interaction technique.

  • Objective Evaluation of Components of Colour Distortions due to Image Compression

    Amal PUNCHIHEWA  Jonathan ARMSTRONG  Seiichiro HANGAI  Takayuki HAMAMOTO  

     
    PAPER-Evaluation

      Vol:
    E92-A No:12
      Page(s):
    3307-3312

    This paper presents a novel approach of analysing colour bleeding caused by image compression. This is achieved by isolating two components of colour bleeding, and evaluating these components separately. Although these specific components of colour bleeding have not been studied with great detail in the past, with the use of a synthetic test pattern -- similar to the colour bars used to test analogue television transmissions -- we have successfully isolated, and evaluated: "colour blur" and "colour ringing," as two separate components of colour bleeding artefact. We have also developed metrics for these artefacts, and tested these derived metrics in a series of trials aimed to test the colour reproduction performance of a JPEG codec, and a JPEG2000 codec -- both implemented by the developer IrfanView. The algorithms developed to measure these artefact metrics proved to be effective tools for evaluating and benchmarking the performance of similar codecs, or different implementations of the same codecs.

  • Performance Analysis of Complex CDMA Using Complex Chaotic Spreading Sequence with Constant Power

    Ryo TAKAHASHI  Ken UMENO  

     
    LETTER-Nonlinear Problems

      Vol:
    E92-A No:12
      Page(s):
    3394-3397

    A performance of the complex chaotic spreading sequences with constant power is investigated in a chip-synchronous complex CDMA with a complex scrambling. We estimate a signal-to-interference ratio (SIR) and a bit error rate (BER). An exact invariant measure of the complex chaotic spreading sequence can be obtained. Therefore, the SIR can be calculated analytically. The result can be used as one of the criteria for evaluating the performance of the complex CDMA using the chaotic spreading sequences.

  • A Novel Composite Right/Left-Handed Rectangular Waveguide with Tilted Corrugations and Its Application to Millimeter-Wave Frequency-Scanning Antenna

    Toru IWASAKI  Hirokazu KAMODA  Takao KUKI  

     
    PAPER-Antennas and Propagation

      Vol:
    E92-B No:12
      Page(s):
    3843-3849

    A novel structure for a composite right/left-handed (CRLH) corrugated waveguide in the millimeter-wave band is proposed. The CRLH waveguide is composed of a rectangular waveguide with tilted corrugations on its bottom broad wall. By operating above and below the cutoff frequency of the dominant mode of the rectangular waveguide, the CRLH waveguide provides, respectively, an inherent series inductance and shunt capacitance, and an inherent shunt inductance. Moreover, the tilted corrugations provide a series inductance and a series capacitance, which can support CRLH propagation. A frequency-scanning antenna using this CRLH waveguide is also studied numerically and experimentally. The results demonstrate that the antenna can provide backward-to-forward beam scanning, including the broadside direction. A scanning angle from -9.9 to +2.2 is achieved within a 1.8-GHz frequency range in the 60-GHz band.

  • Hash Functions and Information Theoretic Security

    Nasour BAGHERI  Lars R. KNUDSEN  Majid NADERI  Sφren S. THOMSEN  

     
    LETTER-Cryptography and Information Security

      Vol:
    E92-A No:12
      Page(s):
    3401-3403

    Information theoretic security is an important security notion in cryptography as it provides a true lower bound for attack complexities. However, in practice attacks often have a higher cost than the information theoretic bound. In this paper we study the relationship between information theoretic attack costs and real costs. We show that in the information theoretic model, many well-known and commonly used hash functions such as MD5 and SHA-256 fail to be preimage resistant.

  • Compact Rat-Race Hybrid Coupler Using Slow Wave and Left-Handed Transmission Lines

    Tack-Gyu KIM  Bomson LEE  

     
    BRIEF PAPER-Microwaves, Millimeter-Waves

      Vol:
    E92-C No:12
      Page(s):
    1535-1537

    Based on provided convenient design equations for slow wave transmission lines and metamaterial line, a very compact rat-race hybrid coupler is proposed using three slow wave lines and one metamaterial line. At the design frequency of 2 GHz, the size of the proposed coupler is 2.3 cm2.7 cm, which is a 74% reduction compared with the conventional one. Despite the considerable size reduction, the theoretical bandwidths based on | S11|, | S31|, ∠ S21-∠ S31, and ∠ S24-∠ S34, have been improved by 9%, 7%, 31%, and 59%, respectively. The measured performances are in reasonable agreement with the theoretical ones.

  • Heuristic Instruction Scheduling Algorithm Using Available Distance for Partial Forwarding Processor

    Takuji HIEDA  Hiroaki TANAKA  Keishi SAKANUSHI  Yoshinori TAKEUCHI  Masaharu IMAI  

     
    PAPER-Embedded, Real-Time and Reconfigurable Systems

      Vol:
    E92-A No:12
      Page(s):
    3258-3267

    Partial forwarding is a design method to place forwarding paths on a part of processor pipeline. Hardware cost of processor can be reduced without performance loss by partial forwarding. However, compiler with the instruction scheduler which considers partial forwarding structure of the target processor is required since conventional scheduling algorithm cannot make the most of partial forwarding structure. In this paper, we propose a heuristic instruction scheduling method for processors with partial forwarding structure. The proposed algorithm uses available distance to schedule instructions which are suitable for the target partial forwarding processor. Experimental results show that the proposed method generates near-optimal solutions in practical time and some of the optimized codes for partial forwarding processor run in the shortest time among the target processors. It also shows that the proposed method is superior to hazard detection unit.

  • X-Handling for Current X-Tolerant Compactors with More Unknowns and Maximal Compaction

    Youhua SHI  Nozomu TOGAWA  Masao YANAGISAWA  Tatsuo OHTSUKI  

     
    PAPER-Logic Synthesis, Test and Verfication

      Vol:
    E92-A No:12
      Page(s):
    3119-3127

    This paper presents a novel X-handling technique, which removes the effect of unknowns on compacted test response with maximal compaction ratio. The proposed method combines with the current X-tolerant compactors and inserts masking cells on scan paths to selectively mask X's. By doing this, the number of unknown responses in each scan-out cycle could be reduced to a reasonable level such that the target X-tolerant compactor would tolerate with guaranteed possible error detection. It guarantees no test loss due to the effect of X's, and achieves the maximal compaction that the target response compactor could provide as well. Moreover, because the masking cells are only inserted on the scan paths, it has no performance degradation of the designs. Experimental results demonstrate the effectiveness of the proposed method.

  • Computational Complexity of Liveness Problem of Normal Petri Net

    Atsushi OHTA  Kohkichi TSUJI  

     
    PAPER

      Vol:
    E92-A No:11
      Page(s):
    2717-2722

    Petri net is a powerful modeling tool for concurrent systems. Liveness, which is a problem to verify there exists no local deadlock, is one of the most important properties of Petri net to analyze. Computational complexity of liveness of a general Petri net is deterministic exponential space. Liveness is studied for subclasses of Petri nets to obtain necessary and sufficient conditions that need less computational cost. These are mainly done using a subset of places called siphons. CS-property, which denotes that every siphon has token(s) in every reachable marking, in one of key properties in liveness analysis. On the other hand, normal Petri net is a subclass of Petri net whose reachability set can be effectively calculated. This paper studies computational complexity of liveness problem of normal Petri nets. First, it is shown that liveness of a normal Petri net is equivalent to cs-property. Then we show this problem is co-NP complete by deriving a nondeterministic algorithm for non-liveness which is similar to the algorithm for liveness suggested by Howell et al. Lastly, we study structural feature of bounded Petri net where liveness and cs-property are equivalent. From this consideration, liveness problem of bounded normal Petri net is shown to be deterministic polynomial time complexity.

  • Shift-Invariant Sparse Image Representations Using Tree-Structured Dictionaries

    Makoto NAKASHIZUKA  Hidenari NISHIURA  Youji IIGUNI  

     
    PAPER-Image Processing

      Vol:
    E92-A No:11
      Page(s):
    2809-2818

    In this study, we introduce shift-invariant sparse image representations using tree-structured dictionaries. Sparse coding is a generative signal model that approximates signals by the linear combinations of atoms in a dictionary. Since a sparsity penalty is introduced during signal approximation and dictionary learning, the dictionary represents the primal structures of the signals. Under the shift-invariance constraint, the dictionary comprises translated structuring elements (SEs). The computational cost and number of atoms in the dictionary increase along with the increasing number of SEs. In this paper, we propose an algorithm for shift-invariant sparse image representation, in which SEs are learnt with a tree-structured approach. By using a tree-structured dictionary, we can reduce the computational cost of the image decomposition to the logarithmic order of the number of SEs. We also present the results of our experiments on the SE learning and the use of our algorithm in image recovery applications.

  • Improvement of Mode Distribution in a Triangular Prism Reverberation Chamber by QRS Diffuser

    Eugene RHEE  Joong-Geun RHEE  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Vol:
    E92-B No:11
      Page(s):
    3478-3483

    This paper presents the field uniformity characteristics in a triangular prism reverberation chamber that can be substituted for an open area test site or an anechoic chamber to measure electromagnetic interference. To improve size problems of a stirrer that is an official unit to generate a uniform field in the reverberation chamber, we suggest a diffuser of Quadratic Residue Sequence method. To validate the substitution of a diffuser for a stirrer, a diffuser is designed for 1-3 GHz, and three types of equilateral triangular prism reverberation chambers are modeled. Afterwards, the field distributions in these three reverberation chambers are both simulated and tested. Using XFDTD 6.2 of finite difference time domain method, field deviations of each structure are simulated and compared to each other. An evaluation of field uniformity is done by cumulative probability distribution which is specified in the IEC 61000-4-21. The result shows that the field uniformity in the chamber is within 6 dB tolerance and also within 3 dB standard deviation, which means a diffuser can satisfy the requirement of international standards.

  • Modular Conformance Testing and Assume-Guarantee Verification for Evolving Component-Based Software

    Ngoc Hung PHAM  Toshiaki AOKI  Takuya KATAYAMA  

     
    PAPER

      Vol:
    E92-A No:11
      Page(s):
    2772-2780

    This paper proposes a framework for modular verification of evolving component-based software. This framework includes two stages: modular conformance testing for updating inaccurate models of the evolved components and modular verification for evolving component-based software. When a component is evolved after adapting some refinements, the proposed framework focuses on this component and its model in order to update the model and recheck the whole evolved system. The framework also reuses the previous verification results and the previous models of the evolved components to reduce the number of steps required in the model update and modular verification processes. An implementation and some experimental results are presented.

1701-1720hit(3945hit)