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[Keyword] EMP(607hit)

81-100hit(607hit)

  • A Data Fusion-Based Fire Detection System

    Ying-Yao TING  Chi-Wei HSIAO  Huan-Sheng WANG  

     
    PAPER-Technologies for Knowledge Support Platform

      Pubricized:
    2018/01/19
      Vol:
    E101-D No:4
      Page(s):
    977-984

    To prevent constraints or defects of a single sensor from malfunctions, this paper proposes a fire detection system based on the Dempster-Shafer theory with multi-sensor technology. The proposed system operates in three stages: measurement, data reception and alarm activation, where an Arduino is tasked with measuring and interpreting the readings from three types of sensors. Sensors under consideration involve smoke, light and temperature detection. All the measured data are wirelessly transmitted to the backend Raspberry Pi for subsequent processing. Within the system, the Raspberry Pi is used to determine the probability of fire events using the Dempster-Shafer theory. We investigate moderate settings of the conflict coefficient and how it plays an essential role in ensuring the plausibility of the system's deduced results. Furthermore, a MySQL database with a web server is deployed on the Raspberry Pi for backlog and data analysis purposes. In addition, the system provides three notification services, including web browsing, smartphone APP, and short message service. For validation, we collected the statistics from field tests conducted in a controllable and safe environment by emulating fire events happening during both daytime and nighttime. Each experiment undergoes the No-fire, On-fire and Post-fire phases. Experimental results show an accuracy of up to 98% in both the No-fire and On-fire phases during the daytime and an accuracy of 97% during the nighttime under reasonable conditions. When we take the three phases into account, the accuracy in the daytime and nighttime increase to 97% and 89%, respectively. Field tests validate the efficiency and accuracy of the proposed system.

  • Static Representation Exposing Spatial Changes in Spatio-Temporal Dependent Data

    Hiroki CHIBA  Yuki HYOGO  Kazuo MISUE  

     
    PAPER-Elemental Technologies for human behavior analysis

      Pubricized:
    2018/01/19
      Vol:
    E101-D No:4
      Page(s):
    933-943

    Spatio-temporal dependent data, such as weather observation data, are data of which the attribute values depend on both time and space. Typical methods for the visualization of such data include plotting the attribute values at each point in time on a map and displaying series of the maps in chronological order with animation, or displaying them by juxtaposing horizontally or vertically. However, these methods are problematic in that they compel readers interested in grasping the spatial changes of the attribute values to memorize the representations on the maps. The problem is exacerbated by considering that the longer the time-period covered by the data, the higher the cognitive load. In order to solve these problems, the authors propose a visualization method capable of overlaying the representations of multiple instantaneous values on a single static map. This paper explains the design of the proposed method and reports two experiments conducted by the authors to investigate the usefulness of the method. The experimental results show that the proposed method is useful in terms of the speed and accuracy with which it reads the spatial changes and its ability to present data with long time series efficiently.

  • A Color Restoration Method for Irreversible Thermal Paint Based on Atmospheric Scattering Model

    Zhan WANG  Ping-an DU  Jian LIU  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2017/12/08
      Vol:
    E101-D No:3
      Page(s):
    826-829

    Irreversible thermal paints or temperature sensitive paints are a kind of special temperature sensor which can indicate the temperature grad by judging the color change and is widely used for off-line temperature measurement during aero engine test. Unfortunately, the hot gases flow within the engine during measuring always make the paint color degraded, which means a serious saturation reduction and contrast loss of the paint colors. This phenomenon makes it more difficult to interpret the thermal paint test results. Present contrast enhancement algorithms can significantly increase the image contrast but can't protect the hue feature of the paint images effectively, which always cause color shift. In this paper, we propose a color restoration method for thermal paint image. This method utilizes the atmospheric scattering model to restore the lost contrast and saturation information, so that the hue can be protected and the temperature can be precisely interpreted based on the image.

  • Noise Temperature Approximations for Offset Gregorian Reflector Systems

    Robert LEHMENSIEK  Dirk I. L. DE VILLIERS  

     
    PAPER-Antennas

      Pubricized:
    2017/08/22
      Vol:
    E101-B No:2
      Page(s):
    332-339

    Predicting the receiving sensitivity of an offset Gregorian reflector system antenna requires an accurate prediction of the antenna noise temperature. Calculating the antenna noise temperature is computationally intensive especially for the electrically larger reflector systems. Using the main reflector masking technique, which removes the main reflector from the calculation domain, considerably reduces the computation cost. For an electrically smaller reflector system, diffraction effects affect the accuracy of this technique. Recently an improvement to the technique was proposed that introduces diffraction compensation correction factors. In this paper we introduce new compensation factor and interpolation techniques that improve the accuracy of the approximated antenna noise temperature calculation. The techniques are applied to several offset Gregorian reflector systems similar to those considered for the Square Kilometre Array, with various feeds and the accuracy in terms of receiving sensitivity is evaluated. The techniques can reduce the prediction error of the receiving sensitivity for frequency-invariant feeds to fractions of a percent, while maintaining a significant speed-up over direct calculations.

  • Hierarchical Control of Concurrent Discrete Event Systems with Linear Temporal Logic Specifications

    Ami SAKAKIBARA  Toshimitsu USHIO  

     
    INVITED PAPER

      Vol:
    E101-A No:2
      Page(s):
    313-321

    In this paper, we study a control problem of a concurrent discrete event system, where several subsystems are partially synchronized via shared events, under local and global constraints described by linear temporal logic formulas. We propose a hierarchical control architecture consisting of local supervisors and a coordinator. While the supervisors ensure the local requirements, the coordinator decides which shared events to be disabled so as to satisfy the global specification. First, we construct Rabin games to obtain local supervisors. Next, we reduce them based on shared transitions. Finally, we construct a global Rabin game from the reduced supervisors and a deterministic Rabin automaton that accepts every run satisfying the global specification. By solving it, we obtain a coordinator that disables shared events to guarantee the global requirement. Moreover, the concurrent system controlled by the coordinator and the local supervisors is deadlock-free.

  • 25-Gbps 3-mW/Gbps/ch VCSEL Driver Circuit in 65-nm CMOS for Multichannel Optical Transmitter

    Toru YAZAKI  Norio CHUJO  Takeshi TAKEMOTO  Hiroki YAMASHITA  Akira HYOGO  

     
    PAPER

      Vol:
    E101-A No:2
      Page(s):
    402-409

    This paper describes the design and experiment results of a 25Gbps vertical-cavity surface emitting laser (VCSEL) driver circuit for a multi channel optical transmitter. To compensate for the non-linearity of the VCSEL and achieve high speed data rate communication, an asymmetric pre-emphasis technique is proposed for the VCSEL driver. An asymmetric pre-emphasis signal can be created by adjusting the duty ratio of the emphasis signal. The VCSEL driver adopts a double cascode connection that can apply a drive current from a high voltage DC bias and feed-forward compensation that can enhance the band-width for common-cathode VCSEL. For the design of the optical module structure, a two-tier low temperature co-fired ceramics (LTCC) package is adopted to minimize the wire bonding between the signal pad on the LTCC and the anode pad on the VCSEL. This structure and circuit reduces the simulated deterministic jitter from 12.7 to 4.1ps. A test chip was fabricated with the 65-nm standard CMOS process and demonstrated to work as an optical transmitter. An experimental evaluation showed that this VCSEL driver with asymmetric pre-emphasis reduced the total deterministic jitter up to 8.6ps and improved the vertical eye opening ratio by 3% compared with symmetric pre-emphasis at 25Gbps with a PRBS=29-1 test signal. The power consumption of the VCSEL driver was 3.0mW/Gbps/ch at 25Gbps. An optical transmitter including the VCSEL driver achieved 25-Gbps, 4-ch fully optical links.

  • Design and Experimental Evaluation of an Adaptive Output Feedback Control System Based on ASPR-Ness

    Zhe GUAN  Shin WAKITANI  Ikuro MIZUMOTO  Toru YAMAMOTO  

     
    PAPER-Systems and Control

      Vol:
    E100-A No:12
      Page(s):
    2956-2962

    This paper considers a design method of a discrete-time adaptive output feedback control system with a feedforward input based on almost strict positive realness (ASPR-ness). The proposed scheme utilizes the property of ASPR of the controlled plant, and the reference signal is used as feedforward input. The parallel feedforward compensator (PFC) which renders an ASPR augmented controlled plant is also investigated. Besides, it is shown that the output of original plant can track reference signal perfectly without any steady state error. The effectiveness of the proposed scheme is confirmed through a pilot-scale temperature control system.

  • Lossless Image Coding Based on Probability Modeling Using Template Matching and Linear Prediction

    Toru SUMI  Yuta INAMURA  Yusuke KAMEDA  Tomokazu ISHIKAWA  Ichiro MATSUDA  Susumu ITOH  

     
    LETTER-Image Processing

      Vol:
    E100-A No:11
      Page(s):
    2351-2354

    We previously proposed a lossless image coding scheme using example-based probability modeling, wherein the probability density function of image signals was dynamically modeled pel-by-pel. To appropriately estimate the peak positions of the probability model, several examples, i.e., sets of pels whose neighborhoods are similar to the local texture of the target pel to be encoded, were collected from the already encoded causal area via template matching. This scheme primarily makes use of non-local information in image signals. In this study, we introduce a prediction technique into the probability modeling to offer a better trade-off between the local and non-local information in the image signals.

  • High-Speed 3-D Electroholographic Movie Playback Using a Digital Micromirror Device Open Access

    Naoki TAKADA  Masato FUJIWARA  ChunWei OOI  Yuki MAEDA  Hirotaka NAKAYAMA  Takashi KAKUE  Tomoyoshi SHIMOBABA  Tomoyoshi ITO  

     
    INVITED PAPER

      Vol:
    E100-C No:11
      Page(s):
    978-983

    This study involves proposing a high-speed computer-generated hologram playback by using a digital micromirror device for high-definition spatiotemporal division multiplexing electroholography. Consequently, the results indicated that the study successfully reconstructed a high-definition 3-D movie of 3-D objects that was comprised of approximately 900,000 points at 60 fps when each frame was divided into twelve parts.

  • Using Machine Learning for Automatic Estimation of Emphases in Japanese Documents

    Masaki MURATA  Yuki ABE  

     
    LETTER-Natural Language Processing

      Pubricized:
    2017/07/21
      Vol:
    E100-D No:10
      Page(s):
    2669-2672

    We propose a method for automatic emphasis estimation using conditional random fields. In our experiments, the value of F-measure obtained using our proposed method (0.31) was higher than that obtained using a random emphasis method (0.20), a method using TF-IDF (0.21), and a method based on LexRank (0.26). On the contrary, the value of F-measure of obtained using our proposed method (0.28) was slightly worse as compared with that obtained using manual estimation (0.26-0.40, with an average of 0.35).

  • Efficient Soft-Output Lattice-Reduction-Aided MIMO Detector with Low Complexity

    Hyunsub KIM  Jaeseok KIM  

     
    PAPER-Wireless Communication Technologies

      Pubricized:
    2017/04/14
      Vol:
    E100-B No:10
      Page(s):
    1952-1958

    In this paper, an improved lattice reduction (LR)-aided soft-output multiple-input multiple-output (MIMO) detector is proposed. Conventional LR-aided soft-output MIMO detectors involve the empty set problem (ESP), in which an entry with a particular bit in the candidate list might not exist. To overcome the performance degradation resulting from this ESP, a post-processing algorithm that modifies the candidate list is proposed. The proposed algorithm efficiently resolves the ESP by utilizing the near-orthogonality of the lattice-reduced system model so that the bit error rate (BER) performance is enhanced. In addition, as the complexity of the candidate list generation is reduced with the aid of the post-processing algorithm, the overall complexity is also reduced. Simulation results and the complexity comparisons demonstrate that our proposed method lowers the required Eb/No by 4-5 dB at the BER of 10-5 and the complexity by 13%-55%, compared to the conventional method.

  • Enhancing Purchase Behavior Prediction with Temporally Popular Items

    Chen CHEN  Chunyan HOU  Jiakun XIAO  Yanlong WEN  Xiaojie YUAN  

     
    LETTER-Artificial Intelligence, Data Mining

      Pubricized:
    2017/05/30
      Vol:
    E100-D No:9
      Page(s):
    2237-2240

    In the era of e-commerce, purchase behavior prediction is one of the most important issues to promote both online companies' sales and the consumers' experience. The previous researches usually use traditional features based on the statistics and temporal dynamics of items. Those features lead to the loss of detailed items' information. In this study, we propose a novel kind of features based on temporally popular items to improve the prediction. Experiments on the real-world dataset have demonstrated the effectiveness and the efficiency of our proposed method. Features based on temporally popular items are compared with traditional features which are associated with statistics, temporal dynamics and collaborative filter of items. We find that temporally popular items are an effective and irreplaceable supplement of traditional features. Our study shed light on the effectiveness of the combination of popularity and temporal dynamics of items which can widely used for a variety of recommendations in e-commerce sites.

  • A Study on Video Generation Based on High-Density Temporal Sampling

    Yukihiro BANDOH  Seishi TAKAMURA  Atsushi SHIMIZU  

     
    LETTER

      Pubricized:
    2017/06/14
      Vol:
    E100-D No:9
      Page(s):
    2044-2047

    In current video encoding systems, the acquisition process is independent from the video encoding process. In order to compensate for the independence, pre-filters prior to the encoder are used. However, conventional pre-filters are designed under constraints on the temporal resolution, so they are not optimized enough in terms of coding efficiency. By relaxing the restriction on the temporal resolution of current video encoding systems, there is a good possibility to generate a video signal suitable for the video encoding process. This paper proposes a video generation method with an adaptive temporal filter that utilizes a temporally over-sampled signal. The filter is designed based on dynamic-programming. Experimental results show that the proposed method can reduce encoding rate on average by 3.01 [%] compared to the constant mean filter.

  • Hole-Filling Algorithm with Spatio-Temporal Background Information for View Synthesis

    Huu-Noi DOAN  Tien-Dat NGUYEN  Min-Cheol HONG  

     
    PAPER

      Pubricized:
    2017/06/14
      Vol:
    E100-D No:9
      Page(s):
    1994-2004

    This paper presents a new hole-filling method that uses extrapolated spatio-temporal background information to obtain a synthesized free-view. A new background codebook for extracting reliable temporal background information is introduced. In addition, the paper addresses estimating spatial local background to distinguish background and foreground regions so that spatial background information can be extrapolated. Background holes are filled by combining spatial and temporal background information. Finally, exemplar-based inpainting is applied to fill in the remaining holes using a new priority function. The experimental results demonstrated that satisfactory synthesized views can be obtained using the proposed algorithm.

  • Iteration-Free Bi-Dimensional Empirical Mode Decomposition and Its Application

    Taravichet TITIJAROONROJ  Kuntpong WORARATPANYA  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2017/06/19
      Vol:
    E100-D No:9
      Page(s):
    2183-2196

    A bi-dimensional empirical mode decomposition (BEMD) is one of the powerful methods for decomposing non-linear and non-stationary signals without a prior function. It can be applied in many applications such as feature extraction, image compression, and image filtering. Although modified BEMDs are proposed in several approaches, computational cost and quality of their bi-dimensional intrinsic mode function (BIMF) still require an improvement. In this paper, an iteration-free computation method for bi-dimensional empirical mode decomposition, called iBEMD, is proposed. The locally partial correlation for principal component analysis (LPC-PCA) is a novel technique to extract BIMFs from an original signal without using extrema detection. This dramatically reduces the computation time. The LPC-PCA technique also enhances the quality of BIMFs by reducing artifacts. The experimental results, when compared with state-of-the-art methods, show that the proposed iBEMD method can achieve the faster computation of BIMF extraction and the higher quality of BIMF image. Furthermore, the iBEMD method can clearly remove an illumination component of nature scene images under illumination change, thereby improving the performance of text localization and recognition.

  • An Ultra-Low Voltage CMOS Voltage Controlled Oscillator with Process and Temperature Compensation

    Ting-Chou LU  Ming-Dou KER  Hsiao-Wen ZAN  

     
    PAPER-Electronic Circuits

      Vol:
    E100-C No:8
      Page(s):
    675-683

    Process and temperature variations have become a serious concern for ultra-low voltage (ULV) technology. The clock generator is the essential component for the ULV very-large-scale integration (VLSI). MOSFETs that are operated in the sub-threshold region are widely applied for ULV technology. However, MOSFETs at subthreshold region have relatively high variations with process and temperature. In this paper, process and temperature variations on the clock generators have been studied. This paper presents an ultra-low voltage 2.4GHz CMOS voltage controlled oscillator with temperature and process compensation. A new all-digital auto compensated mechanism to reduce process and temperature variation without any laser trimming is proposed. With the compensated circuit, the VCO frequency-drift is 16.6 times the improvements of the uncompensated one as temperature changes. Furthermore, it also provides low jitter performance.

  • A Spatiotemporal Statistical Model for Eyeballs of Human Embryos

    Masashi KISHIMOTO  Atsushi SAITO  Tetsuya TAKAKUWA  Shigehito YAMADA  Hiroshi MATSUZOE  Hidekata HONTANI  Akinobu SHIMIZU  

     
    PAPER-Biological Engineering

      Pubricized:
    2017/04/17
      Vol:
    E100-D No:7
      Page(s):
    1505-1515

    During the development of a human embryo, the position of eyes moves medially and caudally in the viscerocranium. A statistical model of this process can play an important role in embryology by facilitating qualitative analyses of change. This paper proposes an algorithm to construct a spatiotemporal statistical model for the eyeballs of a human embryo. The proposed modeling algorithm builds a statistical model of the spatial coordinates of the eyeballs independently for each Carnegie stage (CS) by using principal component analysis (PCA). In the process, a q-Gaussian distribution with a model selection scheme based on the Aaike information criterion is used to handle a non-Gaussian distribution with a small sample size. Subsequently, it seamlessly interpolates the statistical models of neighboring CSs, and we present 10 interpolation methods. We also propose an estimation algorithm for the CS using our spatiotemporal statistical model. A set of images of eyeballs in human embryos from the Kyoto Collection was used to train the model and assess its performance. The modeling results suggested that information geometry-based interpolation under the assumption of a q-Gaussian distribution is the best modeling method. The average error in CS estimation was 0.409. We proposed an algorithm to construct a spatiotemporal statistical model of the eyeballs of a human embryo and tested its performance using the Kyoto Collection.

  • Semi-Supervised Clustering Based on Exemplars Constraints

    Sailan WANG  Zhenzhi YANG  Jin YANG  Hongjun WANG  

     
    PAPER-Artificial Intelligence, Data Mining

      Pubricized:
    2017/03/21
      Vol:
    E100-D No:6
      Page(s):
    1231-1241

    In general, semi-supervised clustering can outperform unsupervised clustering. Since 2001, pairwise constraints for semi-supervised clustering have been an important paradigm in this field. In this paper, we show that pairwise constraints (ECs) can affect the performance of clustering in certain situations and analyze the reasons for this in detail. To overcome these disadvantages, we first outline some exemplars constraints. Based on these constraints, we then describe a semi-supervised clustering framework, and design an exemplars constraints expectation-maximization algorithm. Finally, standard datasets are selected for experiments, and experimental results are presented, which show that the exemplars constraints outperform the corresponding unsupervised clustering and semi-supervised algorithms based on pairwise constraints.

  • A Novel 3D Gradient LBP Descriptor for Action Recognition

    Zhaoyang GUO  Xin'an WANG  Bo WANG  Zheng XIE  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2017/03/02
      Vol:
    E100-D No:6
      Page(s):
    1388-1392

    In the field of action recognition, Spatio-Temporal Interest Points (STIPs)-based features have shown high efficiency and robustness. However, most of state-of-the-art work to describe STIPs, they typically focus on 2-dimensions (2D) images, which ignore information in 3D spatio-temporal space. Besides, the compact representation of descriptors should be considered due to the costs of storage and computational time. In this paper, a novel local descriptor named 3D Gradient LBP is proposed, which extends the traditional descriptor Local Binary Patterns (LBP) into 3D spatio-temporal space. The proposed descriptor takes advantage of the neighbourhood information of cuboids in three dimensions, which accounts for its excellent descriptive power for the distribution of grey-level space. Experiments on three challenging datasets (KTH, Weizmann and UT Interaction) validate the effectiveness of our approach in the recognition of human actions.

  • Narrow Fingerprint Template Synthesis by Clustering Minutiae Descriptors

    Zhiqiang HU  Dongju LI  Tsuyoshi ISSHIKI  Hiroaki KUNIEDA  

     
    PAPER-Pattern Recognition

      Pubricized:
    2017/03/08
      Vol:
    E100-D No:6
      Page(s):
    1290-1302

    Narrow swipe sensor has been widely used in embedded systems such as smart-phone. However, the size of captured image is much smaller than that obtained by the traditional area sensor. Therefore, the limited template coverage is the performance bottleneck of such kind of systems. Aiming to increase the geometry coverage of templates, a novel fingerprint template feature synthesis scheme is proposed in the present study. This method could synthesis multiple input fingerprints into a wider template by clustering the minutiae descriptors. The proposed method consists of two modules. Firstly, a user behavior-based Registration Pattern Inspection (RPI) algorithm is proposed to select the qualified candidates. Secondly, an iterative clustering algorithm Modified Fuzzy C-Means (MFCM) is proposed to process the large amount of minutiae descriptors and then generate the final template. Experiments conducted over swipe fingerprint database validate that this innovative method gives rise to significant improvements in reducing FRR (False Reject Rate) and EER (Equal Error Rate).

81-100hit(607hit)