The search functionality is under construction.
The search functionality is under construction.

Keyword Search Result

[Keyword] (42807hit)

4781-4800hit(42807hit)

  • Wideband Waveguide Short-Slot 2-Plane Coupler Using Frequency Shift of Propagating Modes

    Dong-Hun KIM  Jiro HIROKAWA  Makoto ANDO  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E101-C No:10
      Page(s):
    815-821

    A wideband design of the waveguide short-slot 2-plane coupler with 2×2 input/output ports is designed, fabricated, and evaluated. Using coupling coefficients of complementary propagating modes which are TE11, TE21, and TE30 modes, the flatness of the output amplitudes of 2-plane coupler is improved. The coupler operates from 4.96GHz to 5.27GHz (bandwidth 6.1%) which is wider than the former coupler without considering the complementary propagating mode from 5.04GHz to 5.17GHz (bandwidth 2.5%).

  • Improving Distantly Supervised Relation Extraction by Knowledge Base-Driven Zero Subject Resolution

    Eun-kyung KIM  Key-Sun CHOI  

     
    LETTER-Natural Language Processing

      Pubricized:
    2018/07/11
      Vol:
    E101-D No:10
      Page(s):
    2551-2558

    This paper introduces a technique for automatically generating potential training data from sentences in which entity pairs are not apparently presented in a relation extraction. Most previous works on relation extraction by distant supervision ignored cases in which a relationship may be expressed via null-subjects or anaphora. However, natural language text basically has a network structure that is composed of several sentences. If they are closely related, this is not expressed explicitly in the text, which can make relation extraction difficult. This paper describes a new model that augments a paragraph with a “salient entity” that is determined without parsing. The entity can create additional tuple extraction environments as potential subjects in paragraphs. Including the salient entity as part of the sentential input may allow the proposed method to identify relationships that conventional methods cannot identify. This method also has promising potential applicability to languages for which advanced natural language processing tools are lacking.

  • Improvement of Isolation Characteristics of Multi-Way Power Divider Using TE10-TEp0 Mode Transducer

    Mitsuyoshi KISHIHARA  Isao OHTA  

     
    BRIEF PAPER-Microwaves, Millimeter-Waves

      Vol:
    E101-C No:10
      Page(s):
    831-835

    Recently, a multi-way TE10 mode power divider based on the TE10-TEp0 mode transducers consisting of a linearly arranged single-mode waveguide (SMWG) and an over-moded waveguide (OMWG) has been reported. However, the multi-way power divider based on the present mode transducer results in poor isolation and output matching characteristics. In this paper, an improvement of the isolation and the output matching characteristics is attempted by inserting the resistive sheets in the OMWG. It is shown that the isolation characteristics of about 20 dB are achieved by adjusting the dimensions of the resistive sheets. The validity of the design results is confirmed by an experiment.

  • Dynamic Fixed-Point Design of Neuromorphic Computing Systems

    Yongshin KANG  Jaeyong CHUNG  

     
    BRIEF PAPER-Microwaves, Millimeter-Waves

      Vol:
    E101-C No:10
      Page(s):
    840-844

    Practical deep neural networks have a number of weight parameters, and the dynamic fixed-point formats have been used to represent them efficiently. The dynamic fixed-point representations share an scaling factor among a group of numbers, and the weights in a layer have been formed into such a group. In this paper, we first explore a design space for dynamic fixed-point neuromorphic computing systems and show that it is indispensable to have a small group size in neuromorphic architectures, because it is appropriate to group the weights associated with a neuron into a group. We then presents a dynamic fixed-point representation designed for neuromorphic computing systems. Our experimental results show that the proposed representation reduces the required weight bitwidth by about 4 bits compared to the conventional fixed-point format.

  • Spectrum-Based Fault Localization Using Fault Triggering Model to Refine Fault Ranking List

    Yong WANG  Zhiqiu HUANG  Rongcun WANG  Qiao YU  

     
    PAPER-Software Engineering

      Pubricized:
    2018/07/04
      Vol:
    E101-D No:10
      Page(s):
    2436-2446

    Spectrum-based fault localization (SFL) is a lightweight approach, which aims at helping debuggers to identity root causes of failures by measuring suspiciousness for each program component being a fault, and generate a hypothetical fault ranking list. Although SFL techniques have been shown to be effective, the fault component in a buggy program cannot always be ranked at the top due to its complex fault triggering models. However, it is extremely difficult to model the complex triggering models for all buggy programs. To solve this issue, we propose two simple fault triggering models (RIPRα and RIPRβ), and a refinement technique to improve fault absolute ranking based on the two fault triggering models, through ruling out some higher ranked components according to its fault triggering model. Intuitively, our approach is effective if a fault component was ranked within top k in the two fault ranking lists outputted by the two fault localization strategies. Experimental results show that our approach can significantly improve the fault absolute ranking in the three cases.

  • Improving Per-Node Computing Efficiency by an Adaptive Lock-Free Scheduling Model

    Zhishuo ZHENG  Deyu QI  Naqin ZHOU  Xinyang WANG  Mincong YU  

     
    PAPER-Fundamentals of Information Systems

      Pubricized:
    2018/07/06
      Vol:
    E101-D No:10
      Page(s):
    2423-2435

    Job scheduling on many-core computers with tens or even hundreds of processing cores is one of the key technologies in High Performance Computing (HPC) systems. Despite many scheduling algorithms have been proposed, scheduling remains a challenge for executing highly effective jobs that are assigned in a single computing node with diverse scheduling objectives. On the other hand, the increasing scale and the need for rapid response to changing requirements are hard to meet with existing scheduling models in an HPC node. To address these issues, we propose a novel adaptive scheduling model that is applied to a single node with a many-core processor; this model solves the problems of scheduling efficiency and scalability through an adaptive optimistic control mechanism. This mechanism exposes information such that all the cores are provided with jobs and the tools necessary to take advantage of that information and thus compete for resources in an uncoordinated manner. At the same time, the mechanism is equipped with adaptive control, allowing it to adjust the number of running tools dynamically when frequent conflict happens. We justify this scheduling model and present the simulation results for synthetic and real-world HPC workloads, in which we compare our proposed model with two widely used scheduling models, i.e. multi-path monolithic and two-level scheduling. The proposed approach outperforms the other models in scheduling efficiency and scalability. Our results demonstrate that the adaptive optimistic control affords significant improvements for HPC workloads in the parallelism of the node-level scheduling model and performance.

  • Uncertain Rule Based Method for Determining Data Currency

    Mohan LI  Jianzhong LI  Siyao CHENG  Yanbin SUN  

     
    PAPER-Data Engineering, Web Information Systems

      Pubricized:
    2018/07/10
      Vol:
    E101-D No:10
      Page(s):
    2447-2457

    Currency is one of the important measurements of data quality. The main purpose of the study on data currency is to determine whether a given data item is up-to-date. Though there are already several works on determining data currency, all the proposed methods have limitations. Some works require timestamps of data items that are not always available, and others are based on certain currency rules that can only decide relevant currency and cannot express uncertain semantics. To overcome the limitations of the previous methods, this paper introduces a new approach for determining data currency based on uncertain currency rules. First, a class of uncertain currency rules is provided to infer the possible valid time for a given data item, and then based on the rules, data currency is formally defined. After that, a polynomial time algorithm for evaluating data currency is given based on the uncertain currency rules. Using real-life data sets, the effectiveness and efficiency of the proposed method are experimentally verified.

  • Individuality-Preserving Gait Pattern Prediction Based on Gait Feature Transitions

    Tsuyoshi HIGASHIGUCHI  Norimichi UKITA  Masayuki KANBARA  Norihiro HAGITA  

     
    PAPER-Pattern Recognition

      Pubricized:
    2018/07/20
      Vol:
    E101-D No:10
      Page(s):
    2501-2508

    This paper proposes a method for predicting individuality-preserving gait patterns. Physical rehabilitation can be performed using visual and/or physical instructions by physiotherapists or exoskeletal robots. However, a template-based rehabilitation may produce discomfort and pain in a patient because of deviations from the natural gait of each patient. Our work addresses this problem by predicting an individuality-preserving gait pattern for each patient. In this prediction, the transition of the gait patterns is modeled by associating the sequence of a 3D skeleton in gait with its continuous-value gait features (e.g., walking speed or step width). In the space of the prediction model, the arrangement of the gait patterns are optimized so that (1) similar gait patterns are close to each other and (2) the gait feature changes smoothly between neighboring gait patterns. This model allows to predict individuality-preserving gait patterns of each patient even if his/her various gait patterns are not available for prediction. The effectiveness of the proposed method is demonstrated quantitatively. with two datasets.

  • RbWL: Recency-Based Static Wear Leveling for Lifetime Extension and Overhead Reduction in NAND Flash Memory Systems

    Sang-Ho HWANG  Jong Wook KWAK  

     
    LETTER-Software System

      Pubricized:
    2018/07/09
      Vol:
    E101-D No:10
      Page(s):
    2518-2522

    In this letter, we propose a static wear leveling technique, called Recency-based Wear Leveling (RbWL). The basic idea of RbWL is to execute static wear leveling at minimum levels, because the frequent migrations of cold data by static wear leveling cause significant overhead in a NAND flash memory system. RbWL adjusts the execution frequency according to a threshold value that reflects the lifetime difference of the hot/cold blocks and the total lifetime of the NAND flash memory system. The evaluation results show that RbWL improves the lifetime of NAND flash memory systems by 52%, and it also reduces the overhead of wear leveling from 8% to 42% and from 13% to 51%, in terms of the number of erase operations and the number of page migrations of valid pages, respectively, compared with other algorithms.

  • Twofold Correlation Filtering for Tracking Integration

    Wei WANG  Weiguang LI  Zhaoming CHEN  Mingquan SHI  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2018/07/10
      Vol:
    E101-D No:10
      Page(s):
    2547-2550

    In general, effective integrating the advantages of different trackers can achieve unified performance promotion. In this work, we study the integration of multiple correlation filter (CF) trackers; propose a novel but simple tracking integration method that combines different trackers in filter level. Due to the variety of their correlation filter and features, there is no comparability between different CF tracking results for tracking integration. To tackle this, we propose twofold CF to unify these various response maps so that the results of different tracking algorithms can be compared, so as to boost the tracking performance like ensemble learning. Experiment of two CF methods integration on the data sets OTB demonstrates that the proposed method is effective and promising.

  • Design of Capacitive Coupler in Underwater Wireless Power Transfer Focusing on kQ Product

    Masaya TAMURA  Yasumasa NAKA  Kousuke MURAI  

     
    PAPER

      Vol:
    E101-C No:10
      Page(s):
    759-766

    This paper presents the design of a capacitive coupler for underwater wireless power transfer (U-WPT) focusing on kQ product. Power transfer efficiency hinges on the coupling coefficient k between the couplers and Q-factor of water calculated from the complex permittivity. High efficiency can be achieved by handling k and the Q-factor effectively. First, the pivotal elements on k are derived from the equivalent circuit of the coupler. Next, the frequency characteristic of the Q-factor in tap water is calculated from the measured results. Then, the design parameters in which kQ product has the maximal values are determined. Finally, it is demonstrated that the efficiency of U-WPT with the capacitive coupling designed by our method achieves approximately 80%.

  • Low Bit-Rate Compression Image Restoration through Subspace Joint Regression Learning

    Zongliang GAN  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2018/06/28
      Vol:
    E101-D No:10
      Page(s):
    2539-2542

    In this letter, an effective low bit-rate image restoration method is proposed, in which image denoising and subspace regression learning are combined. The proposed framework has two parts: image main structure estimation by classical NLM denoising and texture component prediction by subspace joint regression learning. The local regression function are learned from denoised patch to original patch in each subspace, where the corresponding compression image patches are employed to generate anchoring points by the dictionary learning approach. Moreover, we extent Extreme Support Vector Regression (ESVR) as multi-variable nonlinear regression to get more robustness results. Experimental results demonstrate the proposed method achieves favorable performance compared with other leading methods.

  • TDOA Estimation Algorithm Based on Generalized Cyclic Correntropy in Impulsive Noise and Cochannel Interference

    Xing CHEN  Tianshuang QIU  Cheng LIU  Jitong MA  

     
    PAPER-Digital Signal Processing

      Vol:
    E101-A No:10
      Page(s):
    1625-1630

    This paper mainly discusses the time-difference-of-arrival (TDOA) estimation problem of digital modulation signal under impulsive noise and cochannel interference environment. Since the conventional TDOA estimation algorithms based on the second-order cyclic statistics degenerate severely in impulsive noise and the TDOA estimation algorithms based on correntropy are out of work in cochannel interference, a novel signal-selective algorithm based on the generalized cyclic correntropy is proposed, which can suppress both impulsive noise and cochannel interference. Theoretical derivation and simulation results demonstrate the effectiveness and robustness of the proposed algorithm.

  • Numerical Simulation of Single-Electron Tunneling in Random Arrays of Small Tunnel Junctions Formed by Percolation of Conductive Nanoparticles

    Yoshinao MIZUGAKI  Hiroshi SHIMADA  Ayumi HIRANO-IWATA  Fumihiko HIROSE  

     
    BRIEF PAPER-Microwaves, Millimeter-Waves

      Vol:
    E101-C No:10
      Page(s):
    836-839

    We numerically simulated electrical properties, i.e., the resistance and Coulomb blockade threshold, of randomly-placed conductive nanoparticles. In simulation, tunnel junctions were assumed to be formed between neighboring particle-particle and particle-electrode connections. On a plane of triangle 100×100 grids, three electrodes, the drain, source, and gate, were defined. After random placements of conductive particles, the connection between the drain and source electrodes were evaluated with keeping the gate electrode disconnected. The resistance was obtained by use of a SPICE-like simulator, whereas the Coulomb blockade threshold was determined from the current-voltage characteristics simulated using a Monte-Carlo simulator. Strong linear correlation between the resistance and threshold voltage was confirmed, which agreed with results for uniform one-dimensional arrays.

  • Recovery Performance of IHT and HTP Algorithms under General Perturbations

    Xiaobo ZHANG  Wenbo XU  Yupeng CUI  Jiaru LIN  

     
    LETTER-Digital Signal Processing

      Vol:
    E101-A No:10
      Page(s):
    1698-1702

    In compressed sensing, most previous researches have studied the recovery performance of a sparse signal x based on the acquired model y=Φx+n, where n denotes the noise vector. There are also related studies for general perturbation environment, i.e., y=(Φ+E)x+n, where E is the measurement perturbation. IHT and HTP algorithms are the classical algorithms for sparse signal reconstruction in compressed sensing. Under the general perturbations, this paper derive the required sufficient conditions and the error bounds of IHT and HTP algorithms.

  • Finding Important People in a Video Using Deep Neural Networks with Conditional Random Fields

    Mayu OTANI  Atsushi NISHIDA  Yuta NAKASHIMA  Tomokazu SATO  Naokazu YOKOYA  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2018/07/20
      Vol:
    E101-D No:10
      Page(s):
    2509-2517

    Finding important regions is essential for applications, such as content-aware video compression and video retargeting to automatically crop a region in a video for small screens. Since people are one of main subjects when taking a video, some methods for finding important regions use a visual attention model based on face/pedestrian detection to incorporate the knowledge that people are important. However, such methods usually do not distinguish important people from passers-by and bystanders, which results in false positives. In this paper, we propose a deep neural network (DNN)-based method, which classifies a person into important or unimportant, given a video containing multiple people in a single frame and captured with a hand-held camera. Intuitively, important/unimportant labels are highly correlated given that corresponding people's spatial motions are similar. Based on this assumption, we propose to boost the performance of our important/unimportant classification by using conditional random fields (CRFs) built upon the DNN, which can be trained in an end-to-end manner. Our experimental results show that our method successfully classifies important people and the use of a DNN with CRFs improves the accuracy.

  • Quadruped Locomotion Patterns Generated by Desymmetrization of Symmetric Central Pattern Generator Hardware Network

    Naruki SASAGAWA  Kentaro TANI  Takashi IMAMURA  Yoshinobu MAEDA  

     
    PAPER-Nonlinear Problems

      Vol:
    E101-A No:10
      Page(s):
    1658-1667

    Reproducing quadruped locomotion from an engineering viewpoint is important not only to control robot locomotion but also to clarify the nonlinear mechanism for switching between locomotion patterns. In this paper, we reproduced a quadruped locomotion pattern, gallop, using a central pattern generator (CPG) hardware network based on the abelian group Z4×Z2, originally proposed by Golubitsky et al. We have already used the network to generate three locomotion patterns, walk, trot, and bound, by controlling the voltage, EMLR, inputted to all CPGs which acts as a signal from the midbrain locomotor region (MLR). In order to generate the gallop and canter patterns, we first analyzed the network symmetry using group theory. Based on the results of the group theory analysis, we desymmetrized the contralateral couplings of the CPG network using a new parameter in addition to EMLR, because, whereas the walk, trot, and bound patterns were able to be generated from the spatio-temporal symmetry of the product group Z4×Z2, the gallop and canter patterns were not. As a result, using a constant element $hat{kappa}$ on Z2, the gallop and canter locomotion patterns were generated by the network on ${f Z}_4+hat{kappa}{f Z}_4$, and actually in this paper, the gallop locomotion pattern was generated on the actual circuit.

  • FOREWORD Open Access

    Naoki SHINOHARA  

     
    FOREWORD

      Vol:
    E101-C No:10
      Page(s):
    718-718
  • MinDoS: A Priority-Based SDN Safe-Guard Architecture for DoS Attacks

    Tao WANG  Hongchang CHEN  Chao QI  

     
    PAPER-Information Network

      Pubricized:
    2018/05/02
      Vol:
    E101-D No:10
      Page(s):
    2458-2464

    Software-defined networking (SDN) has rapidly emerged as a promising new technology for future networks and gained considerable attention from both academia and industry. However, due to the separation between the control plane and the data plane, the SDN controller can easily become the target of denial-of service (DoS) attacks. To mitigate DoS attacks in OpenFlow networks, our solution, MinDoS, contains two key techniques/modules: the simplified DoS detection module and the priority manager. The proposed architecture sends requests into multiple buffer queues with different priorities and then schedules the processing of these flow requests to ensure better controller protection. The results show that MinDoS is effective and adds only minor overhead to the entire SDN/OpenFlow infrastructure.

  • DCD-Based Branch and Bound Detector with Reduced Complexity for MIMO Systems

    Zhi QUAN  Ting TIAN  

     
    PAPER-Wireless Communication Technologies

      Pubricized:
    2018/04/09
      Vol:
    E101-B No:10
      Page(s):
    2230-2238

    In many communications applications, maximum-likelihood decoding reduces to solving an integer least-squares problem, which is NP-hard in the worst case. It has recently been shown that over a wide range of dimensions and SNRs, the branch and bound (BB) algorithm can be used to find the exact solution with an expected complexity that is roughly cubic in the dimension of the problem. However, the computational complexity becomes prohibitive if the SNR is too low and/or the dimension of the problem is too large. The dichotomous coordinate descent (DCD) algorithm provides low complexity, but its detection performance is not as good as that of the BB detector. Two methods are developed to bound the optimal detector cost to reduce the complexity of BB in this paper. These methods are DCD-based detectors for MIMO and multiuser detection in the scenario of a large number of transmitting antennas/users. First, a combined detection technique based on the BB and DCD algorithms is proposed. The technique maintains the advantages of both algorithms and achieves a good trade-off between performance and complexity compared to using only the BB or DCD algorithm. Second, since the first feasible solution obtained from the BB search is the solution of the decorrelating decision feedback (DF) method and because DCD results in better accuracy than the decorrelating DF solution, we propose that the first feasible solution of the BB algorithm be obtained by the box-constrained DCD algorithm rather than the decorrelating DF detector. This method improves the precision of the initial solution and identifies more branches that can be eliminated from the search tree. The results show that the DCD-based BB detector provides optimal detection with reduced worst-case complexity compared to that of the decorrelating DF-based BB detector.

4781-4800hit(42807hit)