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3761-3780hit(20498hit)

  • Resource Allocation and Layer Selection for Scalable Video Streaming over Highway Vehicular Networks

    Ruijian AN  Zhi LIU  Hao ZHOU  Yusheng JI  

     
    PAPER-Intelligent Transport System

      Vol:
    E99-A No:11
      Page(s):
    1909-1917

    How to manage the video streaming in future networks is becoming a more and more challenging issue. Recent studies on vehicular networks depict a new picture of the next generation Intelligent Transport System (ITS), with high level road safety and more comfortable driving experience. To cope with the heterogeneous network development for the next generation cellular network, centralized medium control is promising to be employed upon Road Side Unit (RSU). To accommodate the QoS constraints posed by video services in vehicular networks, the scalable video coding (SVC) scheme in H.264/AVC standard family offers spatial and temporal scalabilities in the video dissemination. In this paper, we target the resource allocation and layer selection problem for the multi-user video streaming over highway scenario, by employing SVC coding scheme for the video contents. We propose a Resource Allocation and Layer Selection (RALS) algorithm, which explicitly takes account of the utility value of each Group Of Picture (GOP) among all the vehicular users. Simulation results show that our proposed RALS algorithm outperforms the comparison schemes in typical scenarios.

  • Micro-Vibration Patterns Generated from Shape Memory Alloy Actuators and the Detection of an Asymptomatic Tactile Sensation Decrease in Diabetic Patients

    Junichi DANJO  Sonoko DANJO  Yu NAKAMURA  Keiji UCHIDA  Hideyuki SAWADA  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2016/08/10
      Vol:
    E99-D No:11
      Page(s):
    2759-2766

    Diabetes mellitus is a group of metabolic diseases that cause high blood sugar due to functional problems with the pancreas or metabolism. Diabetic patients have few subjective symptoms and may experience decreased sensation without being aware of it. The commonly performed tests for sensory disorders are qualitative in nature. The authors pay attention to the decline of the sensitivity of tactile sensations, and develop a non-invasive method to detect the level of tactile sensation using a novel micro-vibration actuator that employs shape-memory alloy wires. Previously, we performed a pilot study that applied the device to 15 diabetic patients and confirmed a significant reduction in the tactile sensation in diabetic patients when compared to healthy subjects. In this study, we focus on the asymptomatic development of decreased sensation associated with diabetes mellitus. The objectives are to examine diabetic patients who are unaware of abnormal or decreased sensation using the quantitative tactile sensation measurement device and to determine whether tactile sensation is decreased in patients compared to healthy controls. The finger method is used to measure the Tactile Sensation Threshold (TST) score of the index and middle fingers using the new device and the following three procedures: TST-1, TST-4, and TST-8. TST scores ranged from 1 to 30 were compared between the two groups. The TST scores were significantly higher for the diabetic patients (P<0.05). The TST scores for the left fingers of diabetic patients and healthy controls were 5.9±6.2 and 2.7±2.9 for TST-1, 15.3±7.0 and 8.7±6.4 for TST-4, and 19.3±7.8 and 12.7±9.1 for TST-8. Our data suggest that the use of the new quantitative tactile sensation measurement device enables the detection of decreased tactile sensation in diabetic patients who are unaware of abnormal or decreased sensation compared to controls.

  • Hybrid TOA/RSSI-Based Wireless Capsule Endoscope Localization with Relative Permittivity Estimation

    Takahiro ITO  Daisuke ANZAI  Jianqing WANG  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:11
      Page(s):
    2442-2449

    When using a wireless capsule endoscope (WCE), it is important to know WCE location. In this paper, we focus on a time of arrival (TOA)-based localization technique, as it has better location estimation performance than other radio frequency-based techniques. However, the propagation speed of signals transmitted from inside of a human body varies depending on which biological tissues they pass through. For this reason, almost all of conventional TOA-based methods have to obtain the relative permittivity of the passed biological tissues or the propagation speed beforehand through another measurement system, i.e., magnetic resonance imaging (MRI) or computational tomography (CT). To avoid such troublesome pre-measurement, we propose a hybrid TOA/received signal strength indicator (RSSI)-based method, which can simultaneously estimate the WCE location and the averaged relative permittivity of the human body. First, we derive the principle of RSSI-based relative permittivity estimation from an finite difference time domain (FDTD) simulation. Second, we combine the TOA-based localization and the proposed RSSI-based relative permittivity estimation, and add them to the particle filter tracking technique. Finally, we perform computer simulations to evaluate the estimation accuracy of the proposed method. The simulation results show that the proposed method can accomplish good localization performance, 1.3mm, without pre-measurement of the human body structure information.

  • Fast Spectral BRDF & BTDF Measurements for Characterization of Displays and Components Open Access

    Pierre BOHER  Thierry LEROUX  Véronique COLLOMB-PATTON  Thibault BIGNON  

     
    INVITED PAPER

      Vol:
    E99-C No:11
      Page(s):
    1255-1263

    In the present paper we show how to obtain rapidly the spectral BRDF and BTDF of different display components or transparent displays using Fourier optics system under different illumination configurations. Results can be used to simulate the entire structure of a LCD display or to predict transparent display performances under various illuminations.

  • Uniform Lying Helix of Cholesteric Liquid Crystals Aligned by means of Slit Coater Method with Electric Treatment Open Access

    Munehiro KIMURA  Naoto ENDO  

     
    INVITED PAPER

      Vol:
    E99-C No:11
      Page(s):
    1240-1243

    A Uniform Lying Helix (ULH) liquid crystal device (LCD) fabricated by utilizing the characteristics of shear flow alignment as well as dielectric anisotropy was demonstrated. Cholesteric liquid crystals with a short helical pitch can exhibit an electric field-induced tilt. These experimental results indicate that it is possible to realize a high-speed response flexible LCD using plastic substrates.

  • Address Power Reduction Method for High-Resolution Plasma Display Panels Using Address Data Smoothing Based on a Visual Masking Effect

    Masahiko SEKI  Masato FUJII  Tomokazu SHIGA  

     
    PAPER

      Vol:
    E99-C No:11
      Page(s):
    1277-1282

    This paper proposes an address power reduction method for plasma display panels (PDPs) using subfield data smoothing based on a visual masking effect. High-resolution, high-frame-rate PDPs have large address power loss caused by parasitic capacitance. Although the address power is reduced by smoothing the subfield data, noise is generated. The proposed method reduces the address power while maintaining the image quality by choosing the smoothing area of the address data based on the visual masking effect. The results of subjective assessment for the images based on smoothed address data indicate that image quality is maintained.

  • Misalignment Tolerance of Pluggable Ballpoint-Pen Interconnect of Graded-Index Plastic Optical Fiber for 4K/8K UHD Display Open Access

    Azusa INOUE  Yasuhiro KOIKE  

     
    INVITED PAPER

      Vol:
    E99-C No:11
      Page(s):
    1271-1276

    We investigate the influence of launching conditions on misalignment tolerance of pluggable ballpoint-pen interconnects, where graded-index plastic optical fibers (GI POFs) are coupled with ball lenses mounted on their end faces. The lateral-misalignment tolerance of the ballpoint-pen connector decreased with an increase in the driving current of a vertical cavity surface emitting laser (VCSEL) under the center launching condition. This was attributed to the VCSEL multimode oscillation, which increased the connector coupling loss through the higher-order guided mode launching in the GI POF and the resulting output beam expansion in the ballpoint-pen connector. The driving-current dependence of the connector coupling loss could be decreased using offset launchings. For a radial launching offset of 20µm, we could obtain coupling losses below 1dB for lateral coupling offsets of ±50µm with little dependence on the driving current. This suggests that data transmission quality for misaligned connection of the GI POFs can be improved further by optimizing launching systems for the ballpoint-pen interconnects.

  • Improvements of Voice Timbre Control Based on Perceived Age in Singing Voice Conversion

    Kazuhiro KOBAYASHI  Tomoki TODA  Tomoyasu NAKANO  Masataka GOTO  Satoshi NAKAMURA  

     
    PAPER-Speech and Hearing

      Pubricized:
    2016/07/21
      Vol:
    E99-D No:11
      Page(s):
    2767-2777

    As one of the techniques enabling individual singers to produce the varieties of voice timbre beyond their own physical constraints, a statistical voice timbre control technique based on the perceived age has been developed. In this technique, the perceived age of a singing voice, which is the age of the singer as perceived by the listener, is used as one of the intuitively understandable measures to describe voice characteristics of the singing voice. The use of statistical voice conversion (SVC) with a singer-dependent multiple-regression Gaussian mixture model (MR-GMM), which effectively models the voice timbre variations caused by a change of the perceived age, makes it possible for individual singers to manipulate the perceived ages of their own singing voices while retaining their own singer identities. However, there still remain several issues; e.g., 1) a controllable range of the perceived age is limited; 2) quality of the converted singing voice is significantly degraded compared to that of a natural singing voice; and 3) each singer needs to sing the same phrase set as sung by a reference singer to develop the singer-dependent MR-GMM. To address these issues, we propose the following three methods; 1) a method using gender-dependent modeling to expand the controllable range of the perceived age; 2) a method using direct waveform modification based on spectrum differential to improve quality of the converted singing voice; and 3) a rapid unsupervised adaptation method based on maximum a posteriori (MAP) estimation to easily develop the singer-dependent MR-GMM. The experimental results show that the proposed methods achieve a wider controllable range of the perceived age, a significant quality improvement of the converted singing voice, and the development of the singer-dependnet MR-GMM using only a few arbitrary phrases as adaptation data.

  • Multiband Automatic Tunable Antenna System Based on the Received Power of a Probe

    Makoto HIGAKI  Shuichi OBAYASHI  Hiroki SHOKI  

     
    PAPER-Antennas and Propagation

      Vol:
    E99-B No:11
      Page(s):
    2390-2398

    This paper proposes a multiband automatic tunable antenna system for wide frequency bands of 704-2690MHz for cellular wireless communication systems. The proposed system controls variable capacitors connected between the antenna and a transmitter based on the received power of a probe. Locating the probe near the tip of the antenna enables frequency-a operation. The antenna is a multiband two-arm monopole antenna printed on a 60mm × 10mm area of a 60mm × 100mm FR-4 printed circuit board (PCB). The probe is a small dipole antenna capacitively coupled with the antenna. Fine-tuning based on simple hill-climbing optimization compensates the mismatch due to the surroundings, e.g., a user's hand/head or desk assuming channel-informed rough-tuning beforehand. A prototype consisting of varicap diodes and some other devices demonstrates automatic tunability.

  • IIR Filter Design Using Multi-Swarm PSO Based on Particle Reallocation Strategy

    Haruna AIMI  Kenji SUYAMA  

     
    PAPER-Digital Signal Processing

      Vol:
    E99-A No:11
      Page(s):
    1947-1954

    In this paper, we study a novel method to avoid a local minimum stagnation in the design problem of IIR (Infinite Impulse Response) filters using PSO (Particle Swarm Optimization). Although PSO is appropriate to solve nonlinear optimization problems, it is reported that a local minimum stagnation occurs due to a strong intensification of particles during the search. Then, multi-swarm PSO based on the particle reallocation strategy is proposed to avoid the local minimum stagnation. In this method, a reallocation space is determined by using some global bests. In this paper, the relationship between the number of swarms and the best value of design error is shown and the effectiveness of the proposed method is shown through several design examples.

  • Flexible Ultra-Thin Liquid Crystal Devices Using Coat-Debond Polyimide Substrates and Etched Post Spacers Open Access

    Yuusuke OBONAI  Yosei SHIBATA  Takahiro ISHINABE  Hideo FUJIKAKE  

     
    INVITED PAPER

      Vol:
    E99-C No:11
      Page(s):
    1228-1233

    We developed flexible LC devices using coat-debond polyimide substrates with a low birefringence and etched post spacers, and clarified that flexible LCDs using post spacers with small spacer distance have a high flexibility without degradation of the image quality. This result ensured the feasibility of flexible LCDs using coat-debond method.

  • Interference Cancellation Employing Replica Selection Algorithm and Neural Network Power Control for MIMO Small Cell Networks

    Michael Andri WIJAYA  Kazuhiko FUKAWA  Hiroshi SUZUKI  

     
    PAPER-Wireless Communication Technologies

      Pubricized:
    2016/06/02
      Vol:
    E99-B No:11
      Page(s):
    2414-2425

    In a network with dense deployment of multiple-input multiple-output (MIMO) small cells, coverage overlap between the small cells produces intercell-interference, which degrades system capacity. This paper proposes an intercell-interference management (IIM) scheme that aims to maximize system capacity by using both power control for intercell-interference coordination (ICIC) on the transmitter side and interference cancellation (IC) on the receiver side. The power control determines transmit power levels at the base stations (BSs) by employing a neural network (NN) algorithm over the backhaul. To further improve the signal to interference plus noise ratio (SINR), every user terminal (UT) employs a multiuser detector (MUD) as IC. The MUD detects not only the desired signals, but also some interfering signals to be cancelled from received signals. The receiver structure consists of branch metric generators (BMGs) and MUD. BMGs suppress residual interference and noise in the received signals by whitening matched filters (WMFs), and then generate metrices by using the WMFs' outputs and symbol candidates that the MUD provides. On the basis of the metrices, the MUD detects both the selected interfering signals and the desired signals. In addition, the MUD determines which interfering signals are detected by an SINR based replica selection algorithm. Computer simulations demonstrate that the SINR based replica selection algorithm, which is combined with channel encoders and packet interleavers, can significantly improve the system bit error rate (BER) and that combining IC at the receiver with NN power control at the transmitter can considerably increase the system capacity. Furthermore, it is shown that choosing the detected interfering signals by the replica selection algorithm can obtain system capacity with comparable loss and less computational complexity compared to the conventional greedy algorithm.

  • Control of Morphology and Alignment of Liquid Crystal Droplets in Molecular-Aligned Polymer for Substrate-Free Displays Open Access

    Daisuke SASAKI  Yosei SHIBATA  Takahiro ISHINABE  Hideo FUJIKAKE  

     
    INVITED PAPER

      Vol:
    E99-C No:11
      Page(s):
    1234-1239

    We have proposed composite films composed of a molecular-aligned polymer and liquid crystal (LC) for substrate-free liquid crystal displays with high-contrast images. We successfully controlled the molecular alignment of the LC and formed molecular-aligned LC droplets in the polymer by controlling the fluidity of the LC/monomer mixture and the curing rate of the monomer.

  • Statistical Measurement of Electromagnetic Noise Characteristics of ESD in Wireless Frequency Bands and Influence Evaluation on Communication Performance

    Ryo NAKAYA  Hidenawo ANDO  Daisuke ANZAI  Jianqing WANG  Osamu FUJIWARA  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Pubricized:
    2016/05/25
      Vol:
    E99-B No:11
      Page(s):
    2399-2405

    Wireless body area networks (BANs) are attracting much attention due to their suitable for healthcare and medical applications. Unfortunately, electrostatic discharge (ESD) is a major electromagnetic (EM) noise source that can degrade wireless communication performance. In this study, we measure EM noise power in the 2.4GHz and 30MHz bands for indirect ESD testing specified in IEC 61000-4-2 standard, and derived a statistical ESD noise model from the measurement results. The ESD noise power was found to follow a lognormal distribution in both 2.4GHz and 30MHz bands. We use this ESD noise model to conduct bit error rate (BER) simulations in a communication channel with additive white Gaussian noise (AWGN) plus ESD noise at 2.4GHz and 30MHz bands. The result is that the BER performance is virtually the same in both bands, and decreases with the signal to noise power ratio (SNR). It is also shown that an error floor exists in the BER performances at both frequencies, which, if the ESD noise power is larger than the Gaussian noise, cannot be improved by increasing the SNR. Although the ESD noise power at 2.4GHz band is nearly 30dB smaller than that at 30MHz band, the signal attenuation along the human body at 2.4GHz band is much larger compared to 30MHz band. This may yield a similar SNR level at 30MHz and 2.4GHz bands in an ESD-dominated environment, so that the 2.4GHz band does not have an obvious merit for BAN applications. Since there are so many in-band interference sources at 2.4GHz band, the 30MHz band seems more promising for vital data transmission in a BAN scenario even in an ESD-dominated 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.

  • Set-to-Set Disjoint Paths Routing in Torus-Connected Cycles

    Antoine BOSSARD  Keiichi KANEKO  

     
    LETTER-Dependable Computing

      Pubricized:
    2016/08/10
      Vol:
    E99-D No:11
      Page(s):
    2821-2823

    Extending the very popular tori interconnection networks[1]-[3], Torus-Connected Cycles (TCC) have been proposed as a novel network topology for massively parallel systems [5]. Here, the set-to-set disjoint paths routing problem in a TCC is solved. In a TCC(k,n), it is proved that paths of lengths at most kn2+2n can be selected in O(kn2) time.

  • A Built-in Test Circuit for Electrical Interconnect Testing of Open Defects in Assembled PCBs

    Widiant  Masaki HASHIZUME  Shohei SUENAGA  Hiroyuki YOTSUYANAGI  Akira ONO  Shyue-Kung LU  Zvi ROTH  

     
    PAPER-Dependable Computing

      Pubricized:
    2016/08/16
      Vol:
    E99-D No:11
      Page(s):
    2723-2733

    In this paper, a built-in test circuit for an electrical interconnect test method is proposed to detect an open defect occurring at an interconnect between an IC and a printed circuit board. The test method is based on measuring the supply current of an inverter gate in the test circuit. A time-varying signal is provided to an interconnect as a test signal by the built-in test circuit. In this paper, the test circuit is evaluated by SPICE simulation and by experiments with a prototyping IC. The experimental results reveal that a hard open defect is detectable by the test method in addition to a resistive open defect and a capacitive open one at a test speed of 400 kHz.

  • Semi-Incremental Recognition of On-Line Handwritten Japanese Text

    Cuong-Tuan NGUYEN  Bilan ZHU  Masaki NAKAGAWA  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2016/07/19
      Vol:
    E99-D No:10
      Page(s):
    2619-2628

    This paper presents a semi-incremental recognition method for on-line handwritten Japanese text and its evaluation. As text becomes longer, recognition time and waiting time become large if it is recognized after it is written (batch recognition). Thus, incremental methods have been proposed with recognition triggered by every stroke but the recognition rates are damaged and more CPU time is incurred. We propose semi-incremental recognition and employ a local processing strategy by focusing on a recent sequence of strokes defined as ”scope” rather than every new stroke. For the latest scope, we build and update a segmentation and recognition candidate lattice and advance the best-path search incrementally. We utilize the result of the best-path search in the previous scope to exclude unnecessary segmentation candidates. This reduces the number of candidate character recognition with the result of reduced processing time. We also reuse the segmentation and recognition candidate lattice in the previous scope for the latest scope. Moreover, triggering recognition processes every several strokes saves CPU time. Experiments made on TUAT-Kondate database show the effectiveness of the proposed semi-incremental recognition method not only in reduced processing time and waiting time, but also in recognition accuracy.

  • Fast Coding-Mode Selection and CU-Depth Prediction Algorithm Based on Text-Block Recognition for Screen Content Coding

    Mengmeng ZHANG  Ang ZHU  Zhi LIU  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2016/07/12
      Vol:
    E99-D No:10
      Page(s):
    2651-2655

    As an important extension of high-efficiency video coding (HEVC), screen content coding (SCC) includes various new coding modes, such as Intra Block Copy (IBC), Palette-based coding (Palette), and Adaptive Color Transform (ACT). These new tools have improved screen content encoding performance. This paper proposed a novel and fast algorithm by classifying Code Units (CUs) as text CUs or non-text CUs. For text CUs, the Intra mode was skipped in the compression process, whereas for non-text CUs, the IBC mode was skipped. The current CU depth range was then predicted according to its adjacent left CU depth level. Compared with the reference software HM16.7+SCM5.4, the proposed algorithm reduced encoding time by 23% on average and achieved an approximate 0.44% increase in Bjøntegaard delta bit rate and a negligible peak signal-to-noise ratio loss.

  • Improved End-to-End Speech Recognition Using Adaptive Per-Dimensional Learning Rate Methods

    Xuyang WANG  Pengyuan ZHANG  Qingwei ZHAO  Jielin PAN  Yonghong YAN  

     
    LETTER-Acoustic modeling

      Pubricized:
    2016/07/19
      Vol:
    E99-D No:10
      Page(s):
    2550-2553

    The introduction of deep neural networks (DNNs) leads to a significant improvement of the automatic speech recognition (ASR) performance. However, the whole ASR system remains sophisticated due to the dependent on the hidden Markov model (HMM). Recently, a new end-to-end ASR framework, which utilizes recurrent neural networks (RNNs) to directly model context-independent targets with connectionist temporal classification (CTC) objective function, is proposed and achieves comparable results with the hybrid HMM/DNN system. In this paper, we investigate per-dimensional learning rate methods, ADAGRAD and ADADELTA included, to improve the recognition of the end-to-end system, based on the fact that the blank symbol used in CTC technique dominates the output and these methods give frequent features small learning rates. Experiment results show that more than 4% relative reduction of word error rate (WER) as well as 5% absolute improvement of label accuracy on the training set are achieved when using ADADELTA, and fewer epochs of training are needed.

3761-3780hit(20498hit)