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[Keyword] IPS(84hit)

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  • U-Net Architecture for Ancient Handwritten Chinese Character Detection in Han Dynasty Wooden Slips

    Hojun SHIMOYAMA  Soh YOSHIDA  Takao FUJITA  Mitsuji MUNEYASU  

     
    PAPER-Image

      Pubricized:
    2023/05/15
      Vol:
    E106-A No:11
      Page(s):
    1406-1415

    Recent character detectors have been modeled using deep neural networks and have achieved high performance in various tasks, such as text detection in natural scenes and character detection in historical documents. However, existing methods cannot achieve high detection accuracy for wooden slips because of their multi-scale character sizes and aspect ratios, high character density, and close character-to-character distance. In this study, we propose a new U-Net-based character detection and localization framework that learns character regions and boundaries between characters. The proposed method enhances the learning performance of character regions by simultaneously learning the vertical and horizontal boundaries between characters. Furthermore, by adding simple and low-cost post-processing using the learned regions of character boundaries, it is possible to more accurately detect the location of a group of characters in a close neighborhood. In this study, we construct a wooden slip dataset. Experiments demonstrated that the proposed method outperformed existing character detection methods, including state-of-the-art character detection methods for historical documents.

  • A Compression Router for Low-Latency Network-on-Chip

    Naoya NIWA  Yoshiya SHIKAMA  Hideharu AMANO  Michihiro KOIBUCHI  

     
    PAPER-Computer System

      Pubricized:
    2022/11/08
      Vol:
    E106-D No:2
      Page(s):
    170-180

    Network-on-Chips (NoCs) are important components for scalable many-core processors. Because the performance of parallel applications is usually sensitive to the latency of NoCs, reducing it is a primary requirement. In this study, a compression router that hides the (de)compression-operation delay is proposed. The compression router (de)compresses the contents of the incoming packet before the switch arbitration is completed, thus shortening the packet length without latency penalty and reducing the network injection-and-ejection latency. Evaluation results show that the compression router improves up to 33% of the parallel application performance (conjugate gradients (CG), fast Fourier transform (FT), integer sort (IS), and traveling salesman problem (TSP)) and 63% of the effective network throughput by 1.8 compression ratio on NoC. The cost is an increase in router area and its energy consumption by 0.22mm2 and 1.6 times compared to the conventional virtual-channel router. Another finding is that off-loading the decompressor onto a network interface decreases the compression-router area by 57% at the expense of the moderate increase in communication latency.

  • An SDN-Based Moving Target Defense as a Countermeasure to Prevent Network Scans Open Access

    Shoya CHIBA  Luis GUILLEN  Satoru IZUMI  Toru ABE  Takuo SUGANUMA  

     
    PAPER

      Pubricized:
    2022/05/27
      Vol:
    E105-B No:11
      Page(s):
    1400-1407

    This paper proposes a Software-Defined Network (SDN)-based Moving Target Defense (MTD) to protect the network from potential scans in a compromised network. As a unique feature, contrary to traditional MTDs, the proposed MTD can work alongside other tools and countermeasures already deployed in the network (e.g., Intrusion Protection and Detection Systems) without affecting its behavior. Through extensive evaluation, we showed the effectiveness of the proposed mechanism compared to existing solutions in preventing scans of different rates without affecting the network and controller performance.

  • DORR: A DOR-Based Non-Blocking Optical Router for 3D Photonic Network-on-Chips

    Meaad FADHEL  Huaxi GU  Wenting WEI  

     
    PAPER-Computer System

      Pubricized:
    2021/01/27
      Vol:
    E104-D No:5
      Page(s):
    688-696

    Recently, researchers paid more attention on designing optical routers, since they are essential building blocks of all photonic interconnection architectures. Thus, improving them could lead to a spontaneous improvement in the overall performance of the network. Optical routers suffer from the dilemma of increased insertion loss and crosstalk, which upraises the power consumed as the network scales. In this paper, we propose a new 7×7 non-blocking optical router based on the Dimension Order Routing (DOR) algorithm. Moreover, we develop a method that can ensure the least number of MicroRing Resonators (MRRs) in an optical router. Therefore, by reducing these optical devices, the optical router proposed can decrease the crosstalk and insertion loss of the network. This optical router is evaluated and compared to Ye's router and the optimized crossbar for 3D Mesh network that uses XYZ routing algorithm. Unlike many other proposed routers, this paper evaluates optical routers not only from router level prospective yet also consider the overall network level condition. The appraisals show that our optical router can reduce the worst-case network insertion loss by almost 8.7%, 46.39%, 39.3%, and 41.4% compared to Ye's router, optimized crossbar, optimized universal OR, and Optimized VOTEX, respectively. Moreover, it decreases the Optical Signal-to-Noise Ratio (OSNR) worst-case by almost 27.92%, 88%, 77%, and 69.6% compared to Ye's router, optimized crossbar, optimized universal OR, and Optimized VOTEX, respectively. It also reduces the power consumption by 3.22%, 23.99%, 19.12%, and 20.18% compared to Ye's router, optimized crossbar, optimized universal OR, and Optimized VOTEX, respectively.

  • Analysis of Pulse Responses by Dispersion Medium with Periodically Conducting Strips

    Ryosuke OZAKI  Tomohiro KAGAWA  Tsuneki YAMASAKI  

     
    BRIEF PAPER

      Pubricized:
    2020/05/14
      Vol:
    E103-C No:11
      Page(s):
    613-616

    In this paper, we analyzed the pulse responses of dispersion medium with periodically conducting strips by using a fast inversion Laplace transform (FILT) method combined with point matching method (PMM) for both the TM and TE cases. Specifically, we investigated the influence of the width and number of the conducting strips on the pulse response and distribution of the electric field.

  • Passage of Faulty Nodes: A Novel Approach for Fault-Tolerant Routing on NoCs

    Yota KUROKAWA  Masaru FUKUSHI  

     
    PAPER

      Vol:
    E102-A No:12
      Page(s):
    1702-1710

    This paper addresses the problem of developing an efficient fault-tolerant routing method for 2D mesh Network-on-Chips (NoCs) to realize dependable and high performance many core systems. Existing fault-tolerant routing methods have two critical problems of high communication latency and low node utilization. Unlike almost all existing methods where packets always detour faulty nodes, we propose a novel and unique approach that packets can pass through faulty nodes. For this approach, we enhance the common NoC architecture by adding switches and links around each node and propose a fault-tolerant routing method with no virtual channels based on the well-known simple XY routing method. Simulation results show that the proposed method reduces average communication latency by about 97.1% compared with the existing method, without sacrificing fault-free nodes.

  • Multi-Service Oriented Stream Data Synchronization Scheme for Multicore Cipher Chips

    Li LI  Fenghua LI  Guozhen SHI  

     
    PAPER

      Vol:
    E102-A No:1
      Page(s):
    48-55

    In cloud computing environments, data processing systems with strong and stochastic stream data processing capabilities are highly desired by multi-service oriented computing-intensive applications. The independeny of different business data streams makes these services very suitable for parallel processing with the aid of multicore processors. Furthermore, for the random crossing of data streams between different services, data synchronization is required. Aiming at the stochastic cross service stream, we propose a hardware synchronization mechanism based on index tables. By using a specifically designed hardware synchronization circuit, we can record the business index number (BIN) of the input and output data flow of the processing unit. By doing so, we can not only obtain the flow control of the job package accessing the processing units, but also guarantee that the work of the processing units is single and continuous. This approach overcomes the high complexity and low reliability of the programming in the software synchronization. As demonstrated by numerical experiment results, the proposed scheme can ensure the validity of the cross service stream, and its processing speed is better than that of the lock-based synchronization scheme. This scheme is applied to a cryptographic server and accelerates the processing speed of the cryptographic service.

  • Scattering of Electromagnetic Waves by Inhomogeneous Dielectric Gratings Loaded with Conducting Strips — Matrix Formulation of Point Matching Method — Open Access

    Tsuneki YAMASAKI  

     
    PAPER

      Vol:
    E102-C No:1
      Page(s):
    3-11

    We have proposed a new method for the scattering of electromagnetic waves by inhomogeneous dielectric gratings loaded with parallel perfectly conducting strips using the combination of improved Fourier series expansion method and point matching method. Numerical results aregiven for the transmission and scattering characteristics for TE and TM cases.

  • A Mechanism of Short-Term Image-Sticking Phenomenon Caused by Flexoelectric Effect in IPS LCD Open Access

    Daisuke INOUE  Tomomi MIYAKE  Mitsuhiro SUGIMOTO  

     
    INVITED PAPER

      Vol:
    E101-C No:11
      Page(s):
    846-850

    We propose a novel mechanism of short-term image-sticking phenomenon in in-plane switching liquid crystal displays (IPS LCDs) that is related to ionic relaxation generated by a vertical electric field caused by a flexoelectric effect. We discuss the differences between electric fields caused by the flexoelectric effect and those caused by DC bias voltage.

  • Network Congestion Minimization Models Based on Robust Optimization

    Bimal CHANDRA DAS  Satoshi TAKAHASHI  Eiji OKI  Masakazu MURAMATSU  

     
    PAPER-Network

      Pubricized:
    2017/09/14
      Vol:
    E101-B No:3
      Page(s):
    772-784

    This paper introduces robust optimization models for minimization of the network congestion ratio that can handle the fluctuation in traffic demands between nodes. The simplest and widely used model to minimize the congestion ratio, called the pipe model, is based on precisely specified traffic demands. However, in practice, network operators are often unable to estimate exact traffic demands as they can fluctuate due to unpredictable factors. To overcome this weakness, we apply robust optimization to the problem of minimizing the network congestion ratio. First, we review existing models as robust counterparts of certain uncertainty sets. Then we consider robust optimization assuming ellipsoidal uncertainty sets, and derive a tractable optimization problem in the form of second-order cone programming (SOCP). Furthermore, we take uncertainty sets to be the intersection of ellipsoid and polyhedral sets, and considering the mirror subproblems inherent in the models, obtain tractable optimization problems, again in SOCP form. Compared to the previous model that assumes an error interval on each coordinate, our models have the advantage of being able to cope with the total amount of errors by setting a parameter that determines the volume of the ellipsoid. We perform numerical experiments to compare our SOCP models with the existing models which are formulated as linear programming problems. The results demonstrate the relevance of our models in terms of congestion ratio and computation time.

  • Mobility Control of TIPS-Pentacene Thin Films Prepared by Blade-Coating Method

    Ryo YAMAMICHI  Takaaki MANAKA  Dai TAGUCHI  Mitsumasa IWAMOTO  

     
    BRIEF PAPER

      Vol:
    E100-C No:2
      Page(s):
    130-132

    Carrier transport characteristics of TIPS-pentacene single crystalline film were controlled by changing the deposition condition of the blade-coating method. Anisotropic carrier transport in the single crystalline grain was visualized by means of the time-resolved microscopic optical second harmonic generation (TRM-SHG) measurement. Slow deposition yields the film with high mobility and large transport anisotropy. For molecular crystals, intermolecular interaction can be modified easily by changing the process condition.

  • HISTORY: An Efficient and Robust Algorithm for Noisy 1-Bit Compressed Sensing

    Biao SUN  Hui FENG  Xinxin XU  

     
    PAPER-Fundamentals of Information Systems

      Pubricized:
    2016/07/06
      Vol:
    E99-D No:10
      Page(s):
    2566-2573

    We consider the problem of sparse signal recovery from 1-bit measurements. Due to the noise present in the acquisition and transmission process, some quantized bits may be flipped to their opposite states. These sign flips may result in severe performance degradation. In this study, a novel algorithm, termed HISTORY, is proposed. It consists of Hamming support detection and coefficients recovery. The HISTORY algorithm has high recovery accuracy and is robust to strong measurement noise. Numerical results are provided to demonstrate the effectiveness and superiority of the proposed algorithm.

  • Effect of Contact Lubricant on Contact Resistance Characteristics — Contact Resistance of Lubricated Surface and Observation of Lubricant Molecules —

    Terutaka TAMAI  Masahiro YAMAKAWA  Yuta NAKAMURA  

     
    PAPER

      Vol:
    E99-C No:9
      Page(s):
    985-991

    The electrical lubricants have been accepted to reduce friction of contacts and to prevent degradation of contact resistance. However, as the lubricant has an electrical insulation property it seems that application to contact surface is unsuitable for contact resistance. These mechanisms in contact interfaces have not fully understood. In this paper, relationships between contact resistance and contact load were examined with both clean and lubricated surfaces. Orientation of the lubricant molecules was observed by high magnification images of STM and AFM. There was no difference in contact resistance characteristics for both clean and lubricated surfaces in spite of lubricants thickness. The molecules were orientated perpendicular to the surface. This fact turns over an established theory of adsorption of non-polar lubricant to surface.

  • Multi-Voltage Variable Pipeline Routers with the Same Clock Frequency for Low-Power Network-on-Chips Systems

    Akram BEN AHMED  Hiroki MATSUTANI  Michihiro KOIBUCHI  Kimiyoshi USAMI  Hideharu AMANO  

     
    PAPER

      Vol:
    E99-C No:8
      Page(s):
    909-917

    In this paper, the Multi-voltage (multi-Vdd) variable pipeline router is proposed to reduce the power consumption of Network-on-Chips (NoCs) designed for Chip Multi-processors (CMPs). The multi-Vdd variable pipeline router adjusts its pipeline depth (i.e., communication latency) and supply voltage level in response to the applied workload. Unlike Dynamic Voltage and Frequency Scaling (DVFS) routers, the operating frequency remains the same for all routers throughout the CMP; thus, omitting the need to synchronize neighboring routers working at different frequencies. Two types of router architectures are presented: a Coarse-Grained Variable Pipeline (CG-VP) router that changes the voltage supplied to the entire router, and a Fine-Grained Variable Pipeline (FG-VP) router that uses a finer power partition. The evaluation results showed that the CG-VP and FG-VP routers achieve a 22.9% and 35.3% power reduction on average with 14% and 23% area overhead in comparison with a baseline router without variable pipelines, respectively. Thanks to the adopted look-ahead mechanism to switch the supply voltage, the performance overhead is only 4.4%.

  • A Full-Flexibility-Guaranteed Pin-Count Reduction Design for General-Purpose Digital Microfluidic Biochips

    Trung Anh DINH  Shigeru YAMASHITA  Tsung-Yi HO  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E99-A No:2
      Page(s):
    570-578

    Different from application-specific digital microfluidic biochips, a general-purpose design has several advantages such as dynamic reconfigurability, and fast on-line evaluation for real-time applications. To achieve such superiority, this design typically activates each electrode in the chip using an individual control pin. However, as the design complexity increases substantially, an order-of-magnitude increase in the number of control pins will significantly affect the manufacturing cost. To tackle this problem, several methods adopting a pin-sharing mechanism for general-purpose designs have been proposed. Nevertheless, these approaches sacrifice the flexibility of droplet movement, and result in an increase of bioassay completion time. In this paper, we present a novel pin-count reduction design methodology for general-purpose microfluidic biochips. Distinguished from previous approaches, the proposed methodology not only reduces the number of control pins significantly but also guarantees the full flexibility of droplet movement to ensure the minimal bioassay completion time.

  • Flexible In-Plane-Switching Liquid Crystal Display Using Stretched Polycarbonate Substrates with Optical Positive A-Plate

    Akihito SATO  Takahiro ISHINABE  Hideo FUJIKAKE  

     
    BRIEF PAPER

      Vol:
    E98-C No:11
      Page(s):
    1039-1042

    Optical compensation of flexible in-plane switching (IPS) mode liquid crystal display (LCD) using polycarbonate substrate with uniaxial optical anisotropy was achieved for wide viewing angle. We theoretically clarified that the slow axis of plastic substrate must be parallel to the absorption axis of polarizer and alignment direction of IPS mode LC. We successfully suppressed a light leakage in the dark state in a wide viewing angle range by fabricated device using uniaxial polycarbonate substrates. These results show that it is possible to realize a high quality flexible LCD using plastic substrates.

  • Millimeter-Wave Ellipsometry Using Interface-Planarization Prism

    Hiroshi YAMAMOTO  Hiroshi ITO  

     
    PAPER-MWP Sensing Technique

      Vol:
    E98-C No:8
      Page(s):
    873-877

    The use of an interface-planarization (IP) prism in millimeter-wave ellipsometry is proposed to achieve reproducible measurements of soft, protean, and non-flat samples. The complex relative dielectric constants of a slice of bovine tissue were successfully measured at frequencies from 90 to 140 GHz using the IP prism to confirm its applicability. The use of the IP prism was found to be advantageous for protecting the sample surface from the desiccation during the measurements.

  • Recommender System Using Implicit Social Information

    Yusheng LI  Meina SONG  Haihong E  

     
    PAPER-Data Engineering, Web Information Systems

      Pubricized:
    2014/10/29
      Vol:
    E98-D No:2
      Page(s):
    346-354

    Social recommendation systems that make use of the user's social information have recently attracted considerable attention. These recommendation approaches partly solve cold-start and data sparsity problems and significantly improve the performance of recommendation systems. The essence of social recommendation methods is to utilize the user's explicit social connections to improve recommendation results. However, this information is not always available in real-world recommender systems. In this paper, a solution to this problem of explicit social information unavailability is proposed. The existing user-item rating matrix is used to compute implicit social information, and then an ISRec (implicit social recommendation algorithm) which integrates this implicit social information and the user-item rating matrix for social recommendation is introduced. Experimental results show that our method performs much better than state-of-the-art approaches; moreover, complexity analysis indicates that our approach can be applied to very large datasets because it scales linearly with respect to the number of observations in the matrices.

  • Fabrication of Step-Edge Vertical-Channel Organic Transistors by Selective Electro-Spray Deposition

    Hiroshi YAMAUCHI  Shigekazu KUNIYOSHI  Masatoshi SAKAI  Kazuhiro KUDO  

     
    PAPER

      Vol:
    E98-C No:2
      Page(s):
    80-85

    Step-edge vertical channel organic field-effect transistors (SVC-OFETs) with a very short channel have been fabricated by a novel selective electrospray deposition (SESD) method. We propose the SESD method for the fabrication of SVC-OFETs based on a 6,13-bis(triisopropyl-silylethynyl) pentacene (TIPS-pentacene) semiconductor layer formed by SESD. In the SESD method, an electric field is applied between the nozzle and selective patterned electrodes on a substrate. We demonstrated that the solution accumulates on the selected electrode pattern by controlling the voltage applied to the electrode.

  • Usefulness of Transmission Ellipsometric Method for Evaluation of Electro-optic Materials

    Toshiki YAMADA  Akira OTOMO  

     
    BRIEF PAPER

      Vol:
    E98-C No:2
      Page(s):
    143-146

    A transmission ellipsometric method without an aperture was recently developed to characterize the electro-optic (EO) performance of EO polymers. The method permits much simpler optical setup compared to the reflection method, and allows easy performance of the incident angle dependence measurements using a conventional glass substrate and uncollimated beam. This paper shows the usefulness of this method for a simple and reliable evaluation of the EO coefficient both for organic and inorganic EO materials, as well as analysis for uniaxial anisotropic materials.

1-20hit(84hit)