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[Keyword] SCE(344hit)

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  • Routing, Modulation Level, Spectrum and Transceiver Assignment in Elastic Optical Networks

    Mingcong YANG  Kai GUO  Yongbing ZHANG  Yusheng JI  

     
    PAPER-Fiber-Optic Transmission for Communications

      Pubricized:
    2017/11/20
      Vol:
    E101-B No:5
      Page(s):
    1197-1209

    The elastic optical network (EON) is a promising new optical technology that uses spectrum resources much more efficiently than does traditional wavelength division multiplexing (WDM). This paper focuses on the routing, modulation level, spectrum and transceiver allocation (RMSTA) problems of the EON. In contrast to previous works that consider only the routing and spectrum allocation (RSA) or routing, modulation level and spectrum allocation (RMSA) problems, we additionally consider the transceiver allocation problem. Because transceivers can be used to regenerate signals (by connecting two transceivers back-to-back) along a transmission path, different regeneration sites on a transmission path result in different spectrum and transceiver usage. Thus, the RMSTA problem is both more complex and more challenging than are the RSA and RMSA problems. To address this problem, we first propose an integer linear programming (ILP) model whose objective is to optimize the balance between spectrum usage and transceiver usage by tuning a weighting coefficient to minimize the cost of network operations. Then, we propose a novel virtual network-based heuristic algorithm to solve the problem and present the results of experiments on representative network topologies. The results verify that, compared to previous works, the proposed algorithm can significantly reduce both resource consumption and time complexity.

  • Detecting TV Program Highlight Scenes Using Twitter Data Classified by Twitter User Behavior and Evaluating It to Soccer Game TV Programs

    Tessai HAYAMA  

     
    PAPER-Datamining Technologies

      Pubricized:
    2018/01/19
      Vol:
    E101-D No:4
      Page(s):
    917-924

    This paper presents a novel TV event detection method for automatically generating TV program digests by using Twitter data. Previous studies of TV program digest generation based on Twitter data have developed TV event detection methods that analyze the frequency time series of tweets that users made while watching a given TV program; however, in most of the previous studies, differences in how Twitter is used, e.g., sharing information versus conversing, have not been taken into consideration. Since these different types of Twitter data are lumped together into one category, it is difficult to detect highlight scenes of TV programs and correctly extract their content from the Twitter data. Therefore, this paper presents a highlight scene detection method to automatically generate TV program digests for TV programs based on Twitter data classified by Twitter user behavior. To confirm the effectiveness of the proposed method, experiments using 49 soccer game TV programs were conducted.

  • Harvest-Then-Transceive: Throughput Maximization in Full-Duplex Wireless-Powered Communication Networks

    KyungRak LEE  SungRyung CHO  JaeWon LEE  Inwhee JOE  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Pubricized:
    2017/09/29
      Vol:
    E101-B No:4
      Page(s):
    1128-1141

    This paper proposes the mesh-topology based wireless-powered communication network (MT-WPCN), which consists of a hybrid-access point (H-AP) and nodes. The H-AP broadcasts energy to all nodes by wireless, and the nodes harvest the energy and then communicate with other nodes including the H-AP. For the communication in the MT-WPCN, we propose the harvest-then-transceive protocol to ensure that the nodes can harvest energy from the H-AP and transmit information selectively to the H-AP or other nodes, which is not supported in most protocols proposed for the conventional WPCN. In the proposed protocol, we consider that the energy harvesting can be interrupted at nodes, since the nodes cannot harvest energy during transmission or reception. We also consider that the harvested energy is consumed by the reception of information from other nodes. In addition, the energy reservation model is required to guarantee the QoS, which reserves the infimum energy to receive information reliably by the transmission power control. Under these considerations, first, we design the half harvest-then-transceive protocol, which indicates that a node transmits information only to other nodes which do not transmit information yet, for investing the effect of the energy harvesting interruption. Secondly, we also design the full harvest-then-transceive protocol for the information exchange among nodes and compatibility with the conventional star-topology based WPCN, which indicates that a node can transmit information to any network unit, i.e., the H-AP and all nodes. We study the sum-throughput maximization in the MT-WPCN based on the half and full harvest-then-transceive protocols, respectively. Furthermore, the amount of harvested energy is analytically compared according to the energy harvesting interruption in the protocols. Simulation results show that the proposed MT-WPCN outperforms the conventional star-topology based WPCN in terms of the sum-throughput maximization, when wireless information transmission among nodes occurs frequently.

  • Using Hierarchical Scenarios to Predict the Reliability of Component-Based Software

    Chunyan HOU  Jinsong WANG  Chen CHEN  

     
    PAPER-Software Engineering

      Pubricized:
    2017/11/07
      Vol:
    E101-D No:2
      Page(s):
    405-414

    System scenarios that derived from system design specification play an important role in the reliability engineering of component-based software systems. Several scenario-based approaches have been proposed to predict the reliability of a system at the design time, most of them adopt flat construction of scenarios, which doesn't conform to software design specifications and is subject to introduce state space explosion problem in the large systems. This paper identifies various challenges related to scenario modeling at the early design stages based on software architecture specification. A novel scenario-based reliability modeling and prediction approach is introduced. The approach adopts hierarchical scenario specification to model software reliability to avoid state space explosion and reduce computational complexity. Finally, the evaluation experiment shows the potential of the approach.

  • Maximum Volume Constrained Graph Nonnegative Matrix Factorization for Facial Expression Recognition

    Viet-Hang DUONG  Manh-Quan BUI  Jian-Jiun DING  Bach-Tung PHAM  Pham The BAO  Jia-Ching WANG  

     
    LETTER-Image

      Vol:
    E100-A No:12
      Page(s):
    3081-3085

    In this work, two new proposed NMF models are developed for facial expression recognition. They are called maximum volume constrained nonnegative matrix factorization (MV_NMF) and maximum volume constrained graph nonnegative matrix factorization (MV_GNMF). They achieve sparseness from a larger simplicial cone constraint and the extracted features preserve the topological structure of the original images.

  • A CMOS Broadband Transceiver with On-Chip Antenna Array and Built-In Pulse-Delay Calibration for Millimeter-Wave Imaging Applications

    Nguyen NGOC MAI-KHANH  Kunihiro ASADA  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E100-C No:12
      Page(s):
    1078-1086

    A fully integrated CMOS pulse transceiver with digital beam-formability for mm-wave active imaging is presented. The on-chip pulse transmitter of the transceiver includes an eight-element antenna array connected to eight pulse transmitters and a built-in relative pulse delay calibration system. The receiver employs a non-coherent detection method by using a FET direct-power detection circuit integrated with an antenna. The receiver dipole-patch antenna derives from the transmitter antenna but is modified with an on-chip DC-bias tail by shorting two arms of the dipole. The bandwidth of the receiver antenna with the DC-bias tail is designed to achieve 50.4-GHz in simulation and to cover the bandwidth of transmitter antennas. The output of the receiver antenna is connected to a resistive self-mixer followed by an on-chip low pass filter and then an amplifier stage. The built-in relative pulse delay calibration system is used to align the pulse delays of each transmitter array elements for the purpose of controlling the beam steering towards imaging objects. Both transmitter and receiver chips are fabricated in a 65-nm CMOS technology process. Measured pulse waveform of the receiver after relatively aligning all Tx's pulses is 0.91 mV (peak-peak) and 3-ns duration with a distance of 25mm between Rx and Tx. Beam steering angles are achieved in measurement by changing the digital delay code of antenna elements. Experimental results show that the proposed on-chip transceiver has an ability of digital transmitted-pulse calibration, controlling of beam-steeting, and pulse detection for active imaging applications.

  • A Novel Discriminative Feature Extraction for Acoustic Scene Classification Using RNN Based Source Separation

    Seongkyu MUN  Suwon SHON  Wooil KIM  David K. HAN  Hanseok KO  

     
    LETTER-Artificial Intelligence, Data Mining

      Pubricized:
    2017/09/14
      Vol:
    E100-D No:12
      Page(s):
    3041-3044

    Various types of classifiers and feature extraction methods for acoustic scene classification have been recently proposed in the IEEE Detection and Classification of Acoustic Scenes and Events (DCASE) 2016 Challenge Task 1. The results of the final evaluation, however, have shown that even top 10 ranked teams, showed extremely low accuracy performance in particular class pairs with similar sounds. Due to such sound classes being difficult to distinguish even by human ears, the conventional deep learning based feature extraction methods, as used by most DCASE participating teams, are considered facing performance limitations. To address the low performance problem in similar class pair cases, this letter proposes to employ a recurrent neural network (RNN) based source separation for each class prior to the classification step. Based on the fact that the system can effectively extract trained sound components using the RNN structure, the mid-layer of the RNN can be considered to capture discriminative information of the trained class. Therefore, this letter proposes to use this mid-layer information as novel discriminative features. The proposed feature shows an average classification rate improvement of 2.3% compared to the conventional method, which uses additional classifiers for the similar class pair issue.

  • A New Approach of Matrix Factorization on Complex Domain for Data Representation

    Viet-Hang DUONG  Manh-Quan BUI  Jian-Jiun DING  Yuan-Shan LEE  Bach-Tung PHAM  Pham The BAO  Jia-Ching WANG  

     
    LETTER-Pattern Recognition

      Pubricized:
    2017/09/15
      Vol:
    E100-D No:12
      Page(s):
    3059-3063

    This work presents a new approach which derives a learned data representation method through matrix factorization on the complex domain. In particular, we introduce an encoding matrix-a new representation of data-that satisfies the simplicial constraint of the projective basis matrix on the field of complex numbers. A complex optimization framework is provided. It employs the gradient descent method and computes the derivative of the cost function based on Wirtinger's calculus.

  • Enhanced Depiction of High Dynamic Images Using Tone Mapping Operator and Chromatic Adaptation Transform

    Ho-Hyoung CHOI  Byoung-Ju YUN  

     
    BRIEF PAPER

      Vol:
    E100-C No:11
      Page(s):
    1031-1034

    The problem of reproducing high dynamic range (HDR) images on devices with a restricted dynamic range has gained a lot of interest in the computer graphics community. Various approaches to this issue exist, spanning several research areas, including computer graphics, image processing, color vision, and physiology. However, most of the approaches to the issue have several serious well-known color distortion problems. Accordingly, this article presents a tone-mapping method. The proposed method comprises the tone-mapping operator and the chromatic adaptation transform. The tone-mapping method is combined with linear and non-linear mapping using visual gamma based on contrast sensitive function (CSF) and using key of scene value, where the visual gamma is adopted to automatically control the dynamic range, parameter free, as well as to avoid both the luminance shift and the hue shift in the displayed images. Furthermore, the key of scene value is used to represent whether the scene was subjectively light, norm, dark. The resulting image is then processed through a chromatic adaptation transform and emphasis lies in human visual perception (HVP). The experiment results show that the proposed method yields better performance of the color rendering over the conventional method in subjective and quantitative quality and color reproduction.

  • Scene Character Recognition Using Coupled Spatial Learning

    Zhong ZHANG  Hong WANG  Shuang LIU  Liang ZHENG  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2017/04/17
      Vol:
    E100-D No:7
      Page(s):
    1546-1549

    Feature representation, as a key component of scene character recognition, has been widely studied and a number of effective methods have been proposed. In this letter, we propose the novel method named coupled spatial learning (CSL) for scene character representation. Different from the existing methods, the proposed CSL method simultaneously discover the spatial context in both the dictionary learning and coding stages. Concretely, we propose to build the spatial dictionary by preserving the corresponding positions of the codewords. Correspondingly, we introduce the spatial coding strategy which utilizes the spatiality regularization to consider the relationship among features in the Euclidean space. Based on the spatial dictionary and spatial coding, the spatial context can be effectively integrated in the visual representations. We verify our method on two widely used databases (ICDAR2003 and Chars74k), and the experimental results demonstrate that our method achieves competitive results compared with the state-of-the-art methods. In addition, we further validate the proposed CSL method on the Caltech-101 database for image classification task, and the experimental results show the good generalization ability of the proposed CSL.

  • Max-Min Fairness for MIMO Interference Channels under CSI Mismatch

    Feng LIU  Conggai LI  Chen HE  Xuan GENG  

     
    LETTER-Communication Theory and Signals

      Vol:
    E100-A No:6
      Page(s):
    1349-1352

    This letter considers the robust transceiver design for multiple-input multiple-output interference channels under channel state information mismatch. According to alternating schemes, an adaptive algorithm is proposed to solve the minimum SINR maximization problem. Simulation results show the convergence and the effectiveness of the proposed algorithm.

  • The Design Challenges of IoT: From System Technologies to Ultra-Low Power Circuits Open Access

    Xiaoyan WANG  Benjamin BÜSZE  Marianne VANDECASTEELE  Yao-Hong LIU  Christian BACHMANN  Kathleen PHILIPS  

     
    INVITED PAPER

      Vol:
    E100-C No:6
      Page(s):
    515-522

    In order to realize an Internet-of-Things (IoT) with tiny sensors integrated in our buildings, our clothing, and the public spaces, battery lifetime and battery size remain major challenges. Power reduction in IoT sensor nodes is determined by both sleep mode as well as active mode contributions. A power state machine, at the system level, is the key to achieve ultra-low average power consumption by alternating the system between active and sleep modes efficiently. While, power consumption in the active mode remains dominant, other power contributions like for timekeeping in standby and sleep conditions are becoming important as well. For example, non-conventional critical blocks, such as crystal oscillator (XO) and resistor-capacitor oscillator (RCO) become more crucial during the design phase. Apart from power reduction, low-voltage operation will further extend the battery life. A 2.4GHz multi-standard radio is presented, as a test case, with an average power consumption in the µW range, and state-of-the-art performance across a voltage supply range from 1.2V to 0.9V.

  • A 20-GHz Differential Push-Push VCO for 60-GHz Frequency Synthesizer toward 256 QAM Wireless Transmission in 65-nm CMOS Open Access

    Yun WANG  Makihiko KATSURAGI  Kenichi OKADA  Akira MATSUZAWA  

     
    PAPER

      Vol:
    E100-C No:6
      Page(s):
    568-575

    This paper present a 20-GHz differential push-push voltage controlled oscillator (VCO) for 60-GHz frequency synthesizer. The 20-GHz VCO consists of a 10-GHz in-phase injection-coupled QVCO (IPIC-QVCO) with tail-filter and a differential output push-push doubler for 20-GHz output. The VCO fabricated in 65-nm CMOS technology, it achieves tuning range of 3 GHz from 17.5 GHz to 20.4 GHz with a phase noise of -113.8 dBc/Hz at 1 MHz offset. The core oscillator consumes up to 71 mW power and a FoM of -180.2 dBc/Hz is achieved.

  • A Novel Procedure for Implementing a Turbo Decoder on a GPU with Coalesced Memory Access

    Heungseop AHN  Seungwon CHOI  

     
    PAPER-Communication Theory and Signals

      Vol:
    E100-A No:5
      Page(s):
    1188-1196

    The sub-blocking algorithm has been known as a core component in implementing a turbo decoder using a Graphic Processing Unit (GPU) to use as many cores in the GPU as possible for parallel processing. However, even though the sub-blocking algorithm allows a large number of threads in a given GPU to be adopted for processing a large number of sub-blocks in parallel, each thread must access the global memory with strided addresses, which results in uncoalesced memory access. Because uncoalesced memory access causes a lot of unnecessary memory transactions, the memory bandwidth efficiency drops significantly, possibly as low as 1/8 in the case of an Long Term Evolution (LTE) turbo decoder, depending upon the compute capability of a GPU. In this paper, we present a novel method for converting uncoalesced memory access into coalesced access in a way that completely recovers the memory bandwidth efficiency to 100% without additional overhead. Our experimental tests, performed with NVIDIA's Geforce GTX 780 Ti GPU, show that the proposed method can enhance the throughput by nearly 30% compared with a conventional turbo decoder that suffers from uncoalesced memory access. Throughput provided by the proposed method has been observed to be 51.4Mbps when the number of iterations and that of sub-blocks are set to 6 and 32, respectively, in our experimental tests, which far exceeds the performance of previous works implemented the Max-Log-MAP algorithm.

  • Thermal Treatment Effect on Morphology and Photo-Physical Properties of Bis-Styrylbenzene Derivatives

    Hiroyuki MOCHIZUKI  

     
    BRIEF PAPER

      Vol:
    E100-C No:2
      Page(s):
    145-148

    Characteristics of the bis-styrylbenzene derivatives with trifluoromethyl or methyl moieties were evaluated in each as-vapor-deposited film, thermally-treated film, and the crystal from the solution. Thermal treatment dramatically changed morphologies and photo-physical properties of the vapor-deposited film.

  • lq Sparsity Penalized STAP Algorithm with Sidelobe Canceler Architecture for Airborne Radar

    Xiaoxia DAI  Wei XIA  Wenlong HE  

     
    LETTER-Information Theory

      Vol:
    E100-A No:2
      Page(s):
    729-732

    Much attention has recently been paid to sparsity-aware space-time adaptive processing (STAP) algorithms. The idea of sparsity-aware technology is commonly based on the convex l1-norm penalty. However, some works investigate the lq (0 < q < 1) penalty which induces more sparsity owing to its lack of convexity. We herein consider the design of an lq penalized STAP processor with a generalized sidelobe canceler (GSC) architecture. The lq cyclic descent (CD) algorithm is utilized with the least squares (LS) design criterion. It is validated through simulations that the lq penalized STAP processor outperforms the existing l1-based counterparts in both convergence speed and steady-state performance.

  • On the Interference Alignment Designs for Secure Multiuser MIMO Systems

    Kha HOANG HA  Thanh TUNG VU  Trung QUANG DUONG  Nguyen-Son VO  

     
    PAPER-Communication Theory and Signals

      Vol:
    E100-A No:2
      Page(s):
    670-679

    In this paper, we propose two secure multiuser multiple-input multiple-output (MIMO) transmission approaches based on interference alignment (IA) in the presence of an eavesdropper. To deal with the information leakage to the eavesdropper as well as the interference signals from undesired transmitters (Txs) at desired receivers (Rxs), our approaches aim to design the transmit precoding and receive subspace matrices to minimize both the total inter-main-link interference and the wiretapped signals (WSs). The first proposed IA scheme focuses on aligning the WSs into proper subspaces while the second one imposes a new structure on the precoding matrices to force the WSs to zero. In each proposed IA scheme, the precoding matrices and the receive subspaces at the legitimate users are alternatively selected to minimize the cost function of a convex optimization problem for every iteration. We provide the feasible conditions and the proofs of convergence for both IA approaches. The simulation results indicate that our two IA approaches outperform the conventional IA algorithm in terms of the average secrecy sum rate.

  • Relating Crosstalk to Plane-Wave Field-to-Wire Coupling

    Flavia GRASSI  Giordano SPADACINI  Keliang YUAN  Sergio A. PIGNARI  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Pubricized:
    2016/05/25
      Vol:
    E99-B No:11
      Page(s):
    2406-2413

    In this work, a novel formulation of crosstalk (XT) is developed, in which the perturbation/loading effect that the generator circuit exerts on the passive part of the receptor circuit is elucidated. Practical conditions (i.e., weak coupling and matching/mismatching of the generator circuit) under which this effect can be neglected are then discussed and exploited to develop an alternative radiated susceptibility (RS) test procedure, which resorts to crosstalk to induce at the terminations of a cable harness the same disturbance that would be induced by an external uniform plane-wave field. The proposed procedure, here developed with reference to typical RS setups foreseen by Standards of the aerospace sector, assures equivalence with field coupling without a priori knowledge and/or specific assumptions on the units connected to the terminations of the cable harness. Accuracy of the proposed scheme of equivalence is assessed by virtual experiments carried out in a full-wave simulation environment.

  • Adaptive Local Thresholding for Co-Localization Detection in Multi-Channel Fluorescence Microscopic Images

    Eisuke ITO  Yusuke TOMARU  Akira IIZUKA  Hirokazu HIRAI  Tsuyoshi KATO  

     
    LETTER-Biological Engineering

      Pubricized:
    2016/07/27
      Vol:
    E99-D No:11
      Page(s):
    2851-2855

    Automatic detection of immunoreactive areas in fluorescence microscopic images is becoming a key technique in the field of biology including neuroscience, although it is still challenging because of several reasons such as low signal-to-noise ratio and contrast variation within an image. In this study, we developed a new algorithm that exhaustively detects co-localized areas in multi-channel fluorescence images, where shapes of target objects may differ among channels. Different adaptive binarization thresholds for different local regions in different channels are introduced and the condition of each segment is assessed to recognize the target objects. The proposed method was applied to detect immunoreactive spots that labeled membrane receptors on dendritic spines of mouse cerebellar Purkinje cells. Our method achieved the best detection performance over five pre-existing methods.

  • Acoustic Scene Analysis Based on Hierarchical Generative Model of Acoustic Event Sequence

    Keisuke IMOTO  Suehiro SHIMAUCHI  

     
    PAPER-Acoustic event detection

      Pubricized:
    2016/07/19
      Vol:
    E99-D No:10
      Page(s):
    2539-2549

    We propose a novel method for estimating acoustic scenes such as user activities, e.g., “cooking,” “vacuuming,” “watching TV,” or situations, e.g., “being on the bus,” “being in a park,” “meeting,” utilizing the information of acoustic events. There are some methods for estimating acoustic scenes that associate a combination of acoustic events with an acoustic scene. However, the existing methods cannot adequately express acoustic scenes, e.g., “cooking,” that have more than one subordinate category, e.g., “frying ingredients” or “plating food,” because they directly associate acoustic events with acoustic scenes. In this paper, we propose an acoustic scene estimation method based on a hierarchical probabilistic generative model of an acoustic event sequence taking into account the relation among acoustic scenes, their subordinate categories, and acoustic event sequences. In the proposed model, each acoustic scene is represented as a probability distribution over their unsupervised subordinate categories, called “acoustic sub-topics,” and each acoustic sub-topic is represented as a probability distribution over acoustic events. Acoustic scene estimation experiments with real-life sounds showed that the proposed method could correctly extract subordinate categories of acoustic scenes.

41-60hit(344hit)