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3961-3980hit(20498hit)

  • Using Received Signal Strength to Detect a Real Wake-Up Call for On-Demand WiFi Wake-Up

    Tomoyuki TANI  Hiroyuki YOMO  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Vol:
    E99-B No:7
      Page(s):
    1609-1618

    This paper considers on-demand WiFi wake-up where a wake-up receiver is installed into each WiFi device. The wake-up receiver detects a wake-up call by finding the predefined length of WiFi frames, which corresponds to a wake-up ID, through envelope detection with limited signal processing. Since each wake-up receiver continuously observes the WiFi channel, an adverse event of False Positive (FP), where a WiFi device is falsely turned on without actual wake-up calls, can occur when the length of non-wake-up, background data frames match with predefined length. In this paper, we suggest using the received signal strength (RSS) of WiFi frames to differentiate the real and false wake-up calls. The proposed scheme exploits the correlation among RSSs of WiFi frames received from a single station located in a fixed position. Using measured RSS data obtained under various settings and different degrees of mobility, we investigate not only the FP reduction rate but also its impact on the probability of detecting real wake-up calls. We also present experimental results obtained with our prototype in which the proposed scheme is implemented.

  • Analysis of Two- and Three-Dimensional Plasmonic Waveguide Band-Pass Filters Using the TRC-FDTD Method

    Jun SHIBAYAMA  Yusuke WADA  Junji YAMAUCHI  Hisamatsu NAKANO  

     
    BRIEF PAPER

      Vol:
    E99-C No:7
      Page(s):
    817-819

    Two plasmonic band-bass filters are analyzed: one is a grating-type filter and the other is a slit-type filter. The former shows a band-pass characteristic with a high transmission for a two-dimensional structure, while the latter exhibits a high transmission even for a three-dimensional structure with a thin metal layer.

  • Subblock-Level Matching Layout for Analog Block-Pair and Its Layout-Dependent Manufacturability Evaluation

    Takuya HIRATA  Ryuta NISHINO  Shigetoshi NAKATAKE  Masaya SHIMOYAMA  Masashi MIYAGAWA  Ryoichi MIYAUCHI  Koichi TANNO  Akihiro YAMADA  

     
    PAPER

      Vol:
    E99-A No:7
      Page(s):
    1381-1389

    This paper presents a layout-dependent manufacturability for analog integrated circuits. We focus on the relative variability of an input op-amp-pair used in an instrumentation amplifier (in-amp). We propose a subblock-level matching layout style such that subblocks of the op-amp-pair are superimposed aiming to suppress the relative variability dependent on the layout. We fabricate chips according to five superposed layout styles and evaluate the relative variability in terms of the DC-offset, so that we demonstrate the most effective layout style. Besides, we provide a manufacturability simulation methodology to evaluate the in-amp considering the relative variability of the op-amp-pair based on the measurement results. Comparing the simulation result and the performances of fabricated in-amps, we are convinced our methodology can evaluate the layout-dependency of the manufacturability by the simulation.

  • Hybrid MIC/CPU Parallel Implementation of MoM on MIC Cluster for Electromagnetic Problems Open Access

    Yan CHEN  Yu ZHANG  Guanghui ZHANG  Xunwang ZHAO  ShaoHua WU  Qing ZHANG  XiaoPeng YANG  

     
    INVITED PAPER

      Vol:
    E99-C No:7
      Page(s):
    735-743

    In this paper, a Many Integrated Core Architecture (MIC) accelerated parallel method of moment (MoM) algorithm is proposed to solve electromagnetic problems in practical applications, where MIC means a kind of coprocessor or accelerator in computer systems which is used to accelerate the computation performed by Central Processing Unit (CPU). Three critical points are introduced in this paper in detail. The first one is the design of the parallel framework, which ensures that the algorithm can run on distributed memory platform with multiple nodes. The hybrid Message Passing Interface (MPI) and Open Multi-Processing (OpenMP) programming model is designed to achieve the purposes. The second one is the out-of-core algorithm, which greatly breaks the restriction of MIC memory. The third one is the pipeline algorithm which overlaps the data movement with MIC computation. The pipeline algorithm successfully hides the communication and thus greatly enhances the performance of hybrid MIC/CPU MoM. Numerical result indicates that the proposed algorithm has good parallel efficiency and scalability, and twice faster performance when compared with the corresponding CPU algorithm.

  • The ASIC Implementation of SM3 Hash Algorithm for High Throughput

    Xiaojing DU  Shuguo LI  

     
    LETTER-Cryptography and Information Security

      Vol:
    E99-A No:7
      Page(s):
    1481-1487

    SM3 is a hash function standard defined by China. Unlike SHA-1 and SHA-2, it is hard for SM3 to speed up the throughput because it has more complicated compression function than other hash algorithm. In this paper, we propose a 4-round-in-1 structure to reduce the number of rounds, and a logical simplifying to move 3 adders and 3 XOR gates from critical path to the non-critical path. Based in SMIC 65nm CMOS technology, the throughput of SM3 can achieve 6.54Gbps which is higher than that of the reported designs.

  • Demonstration of SDN/OpenFlow-Based Path Control for Large-Scale Multi-Domain/Multi-Technology Optical Transport Networks

    Shan GAO  Xiaoyuan CAO  Takehiro SATO  Takaya MIYAZAWA  Sota YOSHIDA  Noboru YOSHIKANE  Takehiro TSURITANI  Hiroaki HARAI  Satoru OKAMOTO  Naoaki YAMANAKA  

     
    PAPER-Network

      Vol:
    E99-B No:7
      Page(s):
    1492-1500

    Software defined networking (SDN) and OpenFlow, which enables the abstraction of vendor/technology-specific attributes, improve the control and management flexibility of optical transport networks. In this paper, we present an interoperability demonstration of SDN/OpenFlow-based optical path control for multi-domain/multi-technology optical transport networks. We also summarize the abstraction approaches proposed for multi-technology network integration at SDN controllers.

  • PAC-k: A Parallel Aho-Corasick String Matching Approach on Graphic Processing Units Using Non-Overlapped Threads

    ThienLuan HO  Seung-Rohk OH  HyunJin KIM  

     
    PAPER-Network Management/Operation

      Vol:
    E99-B No:7
      Page(s):
    1523-1531

    A parallel Aho-Corasick (AC) approach, named PAC-k, is proposed for string matching in deep packet inspection (DPI). The proposed approach adopts graphic processing units (GPUs) to perform the string matching in parallel for high throughput. In parallel string matching, the boundary detection problem happens when a pattern is matched across chunks. The PAC-k approach solves the boundary detection problem because the number of characters to be scanned by a thread can reach the longest pattern length. An input string is divided into multiple sub-chunks with k characters. By adopting the new starting position in each sub-chunk for the failure transition, the required number of threads is reduced by a factor of k. Therefore, the overhead of terminating and reassigning threads is also decreased. In order to avoid the unnecessary overlapped scanning with multiple threads, a checking procedure is proposed that decides whether a new starting position is in the sub-chunk. In the experiments with target patterns from Snort and realistic input strings from DEFCON, throughputs are enhanced greatly compared to those of previous AC-based string matching approaches.

  • Fast Estimation of Field in the Shadow Zone for Finite Cylindrical Structures by Modified Edge Representation (MER) in Compact Range Communication

    Maifuz ALI  Makoto ANDO  

     
    PAPER-Antennas and Propagation

      Vol:
    E99-B No:7
      Page(s):
    1541-1549

    The 60 GHz band compact-range communication is very promising for short-time, short distance communication. Unfortunately, due to the short wavelengths in this frequency band the shadowing effects caused by human bodies, furniture, etc are severe and need to be modeled properly. The numerical methods like the finite-difference time-domain method (FDTD), the finite-element method (FEM), the method of moments (MoM) are unable to compute the field scattered by large objects due to their excessive time and memory requirements. Ray-based approaches like the geometrical theory of diffraction (GTD), uniform geometrical theory of diffraction (UTD), uniform asymptotic theory of diffraction (UAT) are effective and popular solutions but suffer from computation of corner-diffracted field, field at the caustics. Fresnel zone number (FZN) adopted modified edge representation (MER) equivalent edge current (EEC) is an accurate and fast high frequency diffraction technique which expresses the fields in terms of line integration. It adopts distances, rather than the angles used in GTD, UTD or UAT but still provides uniform and highly accurate fields everywhere including geometrical boundaries. Previous work verified this method for planar scatterers. In this work, FZN MER EEC is used to compute field distribution in the millimeter-wave compact range communication in the presence of three dimensional scatterers, where shadowing effects rather than multi-path dominate the radio environments. First, circular cylinder is disintegrated into rectangular plate and circular disks and then FZN MER is applied along with geodesic path loss. The dipole wave scattering from perfectly conducting circular cylinder is discussed as numerical examples.

  • Performance Analysis of DF Relaying Cooperative Systems

    Jingjing WANG  Lingwei XU  Xinli DONG  Xinjie WANG  Wei SHI  T. Aaron GULLIVER  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:7
      Page(s):
    1577-1583

    In this paper, the average symbol error probability (SEP) performance of decode-and-forward (DF) relaying mobile-to-mobile (M2M) systems with transmit antenna selection (TAS) over N-Nakagami fading channels is investigated. The moment generating function (MGF) method is used to derive exact SEP expressions, and the analysis is verified via simulation. The optimal power allocation problem is investigated. Performance results are presented which show that the fading coefficient, number of cascaded components, relative geometrical gain, number of antennas, and power allocation parameter have a significant effect on the SEP.

  • Power Aware Routing Protocols in Wireless Sensor Network

    Mohammed ALSULTAN  Kasim OZTOPRAK  Reza HASSANPOUR  

     
    PAPER-Network

      Vol:
    E99-B No:7
      Page(s):
    1481-1491

    Wireless Sensor Networks (WSNs) have gained importance with a rapid growth in their applications during the past decades. There has also been a rise in the need for energy-efficient and scalable routing along with the data aggregation protocols for the large scale deployments of sensor networks. The traditional routing algorithms suffer from drawbacks such as the presence of one hop long distance data transmissions, very large or very small clusters within a network at the same moment, over-accumulated energy consumption within the cluster-heads (CHs) etc. The lifetime of WSNs is also decreased due to these drawbacks. To overcome them, we have proposed a new method for the Multi-Hop, Far-Zone and Load-Balancing Hierarchical-Based Routing Algorithm for Wireless Sensor Network (MFLHA). Various improvements have been brought forward by MFLHA. The first contribution of the proposed method is the existence of a large probability for the nodes with higher energy to become the CH through the introduction of the energy decision condition and energy-weighted factor within the electing threshold of the CH. Secondly, MFLHA forms a Far-Zone, which is defined as a locus where the sensors can reach the CH with an energy less than a threshold. Finally, the energy consumption by CHs is reduced by the introduction of a minimum energy cost method called the Multi-Hop Inter-Cluster routing algorithm. Our experimental results indicate that MFLHA has the ability to balance the network energy consumption effectively as well as extend the lifetime of the networks. The proposed method outperforms the competitors especially in the middle range distances.

  • An Exact Algorithm for Oblivious Read-Twice Branching Program Satisfiability

    Kazuhisa SETO  Junichi TERUYAMA  

     
    PAPER

      Vol:
    E99-A No:6
      Page(s):
    1019-1024

    We propose an exact algorithm to determine the satisfiability of oblivious read-twice branching programs. Our algorithm runs in $2^{left(1 - Omega( rac{1}{log c}) ight)n}$ time for instances with n variables and cn nodes.

  • D-MENTOR Algorithm for OSPF Protocol under Delay Constrain Supporting Unicast and Multicast Traffic

    Annop MONSAKUL  

     
    PAPER

      Vol:
    E99-B No:6
      Page(s):
    1275-1281

    Designing a backbone IP network, especially to support both unicast and multicast traffic under delay constraints, is a difficult problem. Real network design must consider cost, performance and reliability. Therefore, a simulator can help a network designer to test the functionality of the network before the implementation. This paper proposes a heuristic design algorithm called D-MENTOR, and the algorithm was developed by programming based on Mesh Network Topological Optimization and Routing Version 2 (MENTOR-II) to integrate as a new module of DElite tool. The simulation results show that, in almost all test cases, the proposed algorithm yields lower installation cost.

  • Hybrid Retinal Image Registration Using Mutual Information and Salient Features

    Jaeyong JU  Murray LOEW  Bonhwa KU  Hanseok KO  

     
    LETTER-Biological Engineering

      Pubricized:
    2016/03/01
      Vol:
    E99-D No:6
      Page(s):
    1729-1732

    This paper presents a method for registering retinal images. Retinal image registration is crucial for the diagnoses and treatments of various eye conditions and diseases such as myopia and diabetic retinopathy. Retinal image registration is challenging because the images have non-uniform contrasts and intensity distributions, as well as having large homogeneous non-vascular regions. This paper provides a new retinal image registration method by effectively combining expectation maximization principal component analysis based mutual information (EMPCA-MI) with salient features. Experimental results show that our method is more efficient and robust than the conventional EMPCA-MI method.

  • Optimal Stabilizing Controller for the Region of Weak Attraction under the Influence of Disturbances

    Sasinee PRUEKPRASERT  Toshimitsu USHIO  

     
    PAPER-Formal Methods

      Pubricized:
    2016/05/02
      Vol:
    E99-D No:6
      Page(s):
    1428-1435

    This paper considers an optimal stabilization problem of quantitative discrete event systems (DESs) under the influence of disturbances. We model a DES by a deterministic weighted automaton. The control cost is concerned with the sum of the weights along the generated trajectories reaching the target state. The region of weak attraction is the set of states of the system such that all trajectories starting from them can be controlled to reach a specified set of target states and stay there indefinitely. An optimal stabilizing controller is a controller that drives the states in this region to the set of target states with minimum control cost and keeps them there. We consider two control objectives: to minimize the worst-case control cost (1) subject to all enabled trajectories and (2) subject to the enabled trajectories starting by controllable events. Moreover, we consider the disturbances which are uncontrollable events that rarely occur in the real system but may degrade the control performance when they occur. We propose a linearithmic time algorithm for the synthesis of an optimal stabilizing controller which is robust to disturbances.

  • Computational Complexity of Predicting Periodicity in the Models of Lorentz Lattice Gas Cellular Automata

    Takeo HAGIWARA  Tatsuie TSUKIJI  Zhi-Zhong CHEN  

     
    PAPER

      Vol:
    E99-A No:6
      Page(s):
    1034-1049

    Some diffusive and recurrence properties of Lorentz Lattice Gas Cellular Automata (LLGCA) have been expensively studied in terms of the densities of some of the left/right static/flipping mirrors/rotators. In this paper, for any combination S of these well known scatters, we study the computational complexity of the following problem which we call PERIODICITY on the S-model: given a finite configuration that distributes only those scatters in S, whether a particle visits the starting position periodically or not. Previously, the flipping mirror model and the occupied flipping rotator model have been shown unbounded, i.e. the process is always diffusive [17]. On the other hand, PERIODICITY is shown PSPACE-complete in the unoccupied flipping rotator model [21]. In this paper, we show that PERIODICITY is PSPACE-compete in any S-model that is neither occupied, unbounded, nor static. Particularly, we prove that PERIODICITY in any unoccupied and bounded model containing flipping mirror is PSPACE-complete.

  • Rate-Distortion Optimized Distributed Compressive Video Sensing

    Jin XU  Yuansong QIAO  Quan WEN  

     
    LETTER-Multimedia Environment Technology

      Vol:
    E99-A No:6
      Page(s):
    1272-1276

    Distributed compressive video sensing (DCVS) is an emerging low-complexity video coding framework which integrates the merits of distributed video coding (DVC) and compressive sensing (CS). In this paper, we propose a novel rate-distortion optimized DCVS codec, which takes advantage of a rate-distortion optimization (RDO) model based on the estimated correlation noise (CN) between a non-key frame and its side information (SI) to determine the optimal measurements allocation for the non-key frame. Because the actual CN can be more accurately recovered by our DCVS codec, it leads to more faithful reconstruction of the non-key frames by adding the recovered CN to the SI. The experimental results reveal that our DCVS codec significantly outperforms the legacy DCVS codecs in terms of both objective and subjective performance.

  • Food Image Recognition Using Covariance of Convolutional Layer Feature Maps

    Atsushi TATSUMA  Masaki AONO  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2016/02/23
      Vol:
    E99-D No:6
      Page(s):
    1711-1715

    Recent studies have obtained superior performance in image recognition tasks by using, as an image representation, the fully connected layer activations of Convolutional Neural Networks (CNN) trained with various kinds of images. However, the CNN representation is not very suitable for fine-grained image recognition tasks involving food image recognition. For improving performance of the CNN representation in food image recognition, we propose a novel image representation that is comprised of the covariances of convolutional layer feature maps. In the experiment on the ETHZ Food-101 dataset, our method achieved 58.65% averaged accuracy, which outperforms the previous methods such as the Bag-of-Visual-Words Histogram, the Improved Fisher Vector, and CNN-SVM.

  • Modified t-Distribution Evolutionary Algorithm for Dynamic Deployment of Wireless Sensor Networks

    Xiaolei LIU  Xiaosong ZHANG  Yiqi JIANG  Qingxin ZHU  

     
    PAPER-Artificial Intelligence, Data Mining

      Pubricized:
    2016/03/22
      Vol:
    E99-D No:6
      Page(s):
    1595-1602

    Optimizating the deployment of wireless sensor networks, which is one of the key issues in wireless sensor networks research, helps improve the coverage of the networks and the system reliability. In this paper, we propose an evolutionary algorithm based on modified t-distribution for the wireless sensor by introducing a deployment optimization operator and an intelligent allocation operator. A directed perturbation operator is applied to the algorithm to guide the evolution of the node deployment and to speed up the convergence. In addition, with a new geometric sensor detection model instead of the old probability model, the computing speed is increased by 20 times. The simulation results show that when this algorithm is utilized in the actual scene, it can get the minimum number of nodes and the optimal deployment quickly and effectively.Compared with the existing mainstream swarm intelligence algorithms, this method has satisfied the need for convergence speed and better coverage, which is closer to the theoretical coverage value.

  • Well-Shaped Microelectrode Array Structure for High-Density CMOS Amperometric Electrochemical Sensor Array

    Kiichi NIITSU  Tsuyoshi KUNO  Masayuki TAKIHI  Kazuo NAKAZATO  

     
    BRIEF PAPER

      Vol:
    E99-C No:6
      Page(s):
    663-666

    In this study, a well-shaped microelectrode array (MEA) for fabricating a high-density complementary metal-oxide semiconductor amperometric electrochemical sensor array was designed and verified. By integrating an auxiliary electrode with the well-shaped structure of the MEA, the footprint was reduced and high density and high resolution were also achieved. The results of three-dimensional electrochemical simulations confirmed the effectiveness of the proposed MEA structure and possibility of increasing the density to four times than that achieved by the conventional two-dimensional structure.

  • A 10-bit 20-MS/s Asynchronous SAR ADC with Meta-Stability Detector Using Replica Comparators

    Sang-Min PARK  Yeon-Ho JEONG  Yu-Jeong HWANG  Pil-Ho LEE  Yeong-Woong KIM  Jisu SON  Han-Yeol LEE  Young-Chan JANG  

     
    BRIEF PAPER

      Vol:
    E99-C No:6
      Page(s):
    651-654

    A 10-bit 20-MS/s asynchronous SAR ADC with a meta-stability detector using replica comparators is proposed. The proposed SAR ADC with the area of 0.093mm2 is implemented using a 130-nm CMOS process with a 1.2-V supply. The measured peak ENOBs for the full rail-to-rail differential input signal is 9.6bits.

3961-3980hit(20498hit)