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[Keyword] DR(1315hit)

121-140hit(1315hit)

  • Android Malware Detection Scheme Based on Level of SSL Server Certificate

    Hiroya KATO  Shuichiro HARUTA  Iwao SASASE  

     
    PAPER-Dependable Computing

      Pubricized:
    2019/10/30
      Vol:
    E103-D No:2
      Page(s):
    379-389

    Detecting Android malwares is imperative. As a promising Android malware detection scheme, we focus on the scheme leveraging the differences of traffic patterns between benign apps and malwares. Those differences can be captured even if the packet is encrypted. However, since such features are just statistic based ones, they cannot identify whether each traffic is malicious. Thus, it is necessary to design the scheme which is applicable to encrypted traffic data and supports identification of malicious traffic. In this paper, we propose an Android malware detection scheme based on level of SSL server certificate. Attackers tend to use an untrusted certificate to encrypt malicious payloads in many cases because passing rigorous examination is required to get a trusted certificate. Thus, we utilize SSL server certificate based features for detection since their certificates tend to be untrusted. Furthermore, in order to obtain the more exact features, we introduce required permission based weight values because malwares inevitably require permissions regarding malicious actions. By computer simulation with real dataset, we show our scheme achieves an accuracy of 92.7%. True positive rate and false positive rate are 5.6% higher and 3.2% lower than the previous scheme, respectively. Our scheme can cope with encrypted malicious payloads and 89 malwares which are not detected by the previous scheme.

  • Virtual Address Remapping with Configurable Tiles in Image Processing Applications

    Jae Young HUR  

     
    PAPER-Computer System

      Pubricized:
    2019/10/17
      Vol:
    E103-D No:2
      Page(s):
    309-320

    The conventional linear or tiled address maps can degrade performance and memory utilization when traffic patterns are not matched with an underlying address map. The address map is usually fixed at design time. Accordingly, it is difficult to adapt to given applications. Modern embedded system usually accommodates memory management units (MMUs). As a result, depending on virtual address patterns, the system can suffer from performance overheads due to page table walks. To alleviate this performance overhead, we propose to cluster and rearrange tiles to construct an MMU-aware configurable address map. To construct the clustered tiled map, the generic tile number remapping algorithm is presented. In the presented scheme, an address map is configured based on the adaptive dimensioning algorithm. Considering image processing applications, a design, an analysis, an implementation, and simulations are conducted. The results indicate the proposed method can improve the performance and the memory utilization with moderate hardware costs.

  • An Open Multi-Sensor Fusion Toolbox for Autonomous Vehicles

    Abraham MONRROY CANO  Eijiro TAKEUCHI  Shinpei KATO  Masato EDAHIRO  

     
    PAPER

      Vol:
    E103-A No:1
      Page(s):
    252-264

    We present an accurate and easy-to-use multi-sensor fusion toolbox for autonomous vehicles. It includes a ‘target-less’ multi-LiDAR (Light Detection and Ranging), and Camera-LiDAR calibration, sensor fusion, and a fast and accurate point cloud ground classifier. Our calibration methods do not require complex setup procedures, and once the sensors are calibrated, our framework eases the fusion of multiple point clouds, and cameras. In addition we present an original real-time ground-obstacle classifier, which runs on the CPU, and is designed to be used with any type and number of LiDARs. Evaluation results on the KITTI dataset confirm that our calibration method has comparable accuracy with other state-of-the-art contenders in the benchmark.

  • A Deep Neural Network for Real-Time Driver Drowsiness Detection

    Toan H. VU  An DANG  Jia-Ching WANG  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2019/09/25
      Vol:
    E102-D No:12
      Page(s):
    2637-2641

    We develop a deep neural network (DNN) for detecting driver drowsiness in videos. The proposed DNN model that receives driver's faces extracted from video frames as inputs consists of three components - a convolutional neural network (CNN), a convolutional control gate-based recurrent neural network (ConvCGRNN), and a voting layer. The CNN is to learn facial representations from global faces which are then fed to the ConvCGRNN to learn their temporal dependencies. The voting layer works like an ensemble of many sub-classifiers to predict drowsiness state. Experimental results on the NTHU-DDD dataset show that our model not only achieve a competitive accuracy of 84.81% without any post-processing but it can work in real-time with a high speed of about 100 fps.

  • Hybrid QAM-Based Labels Generated by Two Multi-Level PSK Codes

    Takahiro KODAMA  Gabriella CINCOTTI  

     
    PAPER-Fiber-Optic Transmission for Communications

      Pubricized:
    2019/05/31
      Vol:
    E102-B No:12
      Page(s):
    2199-2204

    Hybrid 200Gchip/s QAM-based opto-electrical labels with high orthogonality are generated using the convolution of optical 16-level and electrical 4-level PSK codes. The combined simultaneous use of optical and electrical encoding increases system flexibility and code orthogonality, as well as code recognition performance. By performing 50 G-class low-speed LN-PM-based electrical processing on the 200 Gchip/s PSK-based optical code labels generated by a multiport optical encoder, the value of PCR indicating the code orthogonality is increased significantly, and the receiver sensitivity is improved by 0.5dB to achieve LER =10-9 in the next-generation optical packet switching networks.

  • Two-Layer Near-Lossless HDR Coding Using Zero-Skip Quantization with Backward Compatibility to JPEG

    Hiroyuki KOBAYASHI  Osamu WATANABE  Hitoshi KIYA  

     
    PAPER-Image

      Vol:
    E102-A No:12
      Page(s):
    1842-1848

    We propose an efficient two-layer near-lossless coding method using an extended histogram packing technique with backward compatibility to the legacy JPEG standard. The JPEG XT, which is the international standard to compress HDR images, adopts a two-layer coding method for backward compatibility to the legacy JPEG standard. However, there are two problems with this two-layer coding method. One is that it does not exhibit better near-lossless performance than other methods for HDR image compression with single-layer structure. The other problem is that the determining the appropriate values of the coding parameters may be required for each input image to achieve good compression performance of near-lossless compression with the two-layer coding method of the JPEG XT. To solve these problems, we focus on a histogram-packing technique that takes into account the histogram sparseness of HDR images. We used zero-skip quantization, which is an extension of the histogram-packing technique proposed for lossless coding, for implementing the proposed near-lossless coding method. The experimental results indicate that the proposed method exhibits not only a better near-lossless compression performance than that of the two-layer coding method of the JPEG XT, but also there are no issue regarding the combination of parameter values without losing backward compatibility to the JPEG standard.

  • An Exact Algorithm for the Arrow Placement Problem in Directed Graph Drawings

    Naoto KIDO  Sumio MASUDA  Kazuaki YAMAGUCHI  

     
    PAPER-Algorithms and Data Structures

      Vol:
    E102-A No:11
      Page(s):
    1481-1489

    We consider the problem of placing arrows, which indicate the direction of each edge in directed graph drawings, without making them overlap other arrows, vertices and edges as much as possible. The following two methods have been proposed for this problem. One is an exact algorithm for the case in which the position of each arrow is restricted to some discrete points. The other is a heuristic algorithm for the case in which the arrow is allowed to move continuously on each edge. In this paper, we assume that the arrow positions are not restricted to discrete points and propose an exact algorithm for the problem of finding an arrow placement such that (a) the weighted sum of the numbers of overlaps with edges, vertices and other arrows is minimized and (b) the sum of the distances between the arrows and their edges' terminal vertices is minimized as a secondary objective. The proposed method solves this problem by reducing it to a mixed integer linear programming problem. Since this is an exponential time algorithm, we add a simple procedure as preprocessing to reduce the running time. Experimental results show that the proposed method can find a better arrow placement than the previous methods and the procedure for reducing the running time is effective.

  • Hybridizing Dragonfly Algorithm with Differential Evolution for Global Optimization Open Access

    MeiJun DUAN  HongYu YANG  Bo YANG  XiPing WU  HaiJun LIANG  

     
    PAPER-Fundamentals of Information Systems

      Pubricized:
    2019/07/17
      Vol:
    E102-D No:10
      Page(s):
    1891-1901

    Due to its simplicity and efficiency, differential evolution (DE) has gained the interest of researchers from various fields for solving global optimization problems. However, it is prone to premature convergence at local minima. To overcome this drawback, a novel hybrid dragonfly algorithm with differential evolution (Hybrid DA-DE) for solving global optimization problems is proposed. Firstly, a novel mutation operator is introduced based on the dragonfly algorithm (DA). Secondly, the scaling factor (F) is adjusted in a self-adaptive and individual-dependent way without extra parameters. The proposed algorithm combines the exploitation capability of DE and exploration capability of DA to achieve optimal global solutions. The effectiveness of this algorithm is evaluated using 30 classical benchmark functions with sixteen state-of-the-art meta-heuristic algorithms. A series of experimental results show that Hybrid DA-DE outperforms other algorithms significantly. Meanwhile, Hybrid DA-DE has the best adaptability to high-dimensional problems.

  • Unconventional Jamming Scheme for Multiple Quadrature Amplitude Modulations Open Access

    Shaoshuai ZHUANSUN  Jun-an YANG  Cong TANG  

     
    PAPER-Transmission Systems and Transmission Equipment for Communications

      Pubricized:
    2019/04/05
      Vol:
    E102-B No:10
      Page(s):
    2036-2044

    It is generally believed that jamming signals similar to communication signals tend to demonstrate better jamming effects. We believe that the above conclusion only works in certain situations. To select the correct jamming scheme for a multi-level quadrature amplitude modulation (MQAM) signal in a complex environment, an optimal jamming method based on orthogonal decomposition (OD) is proposed. The method solves the jamming problem from the perspective of the in-phase dimension and quadrature dimension and exhibits a better jamming effect than normal methods. The method can construct various unconventional jamming schemes to cope with a complex environment and verify the existing jamming schemes. The Experimental results demonstrate that when the jammer ideally knows the received power at the receiver, the proposed method will always have the optimal jamming effects, and the constructed unconventional jamming scheme has an excellent jamming effect compared with normal schemes in the case of a constellation distortion.

  • Motion Track Extraction Based on Empirical Mode Decomposition of Endpoint Effect Suppression for Double-Rotor Drone

    Ziji MA  Kehuang XU  Binghang ZHOU  Jiawei ZHANG  Xun SHAO  

     
    PAPER

      Pubricized:
    2019/05/15
      Vol:
    E102-B No:10
      Page(s):
    1967-1974

    Double-rotor drone shows totally different flight performance. Extracting and analyzing its motion track is very helpful to improve its control approaches to achieve a robust and flight attitude. A novel EMD of endpoint effect suppression is proposed in this paper to accurately extract the DR drone's motion track. The proposed algorithm can effectively suppress the endpoint effect with a complex matching of both position and slope of the record of flight data from sensors. The computer simulation and experiment results both have demonstrated the proposed method's effectiveness and the feasibility of the designed DR drone.

  • Ultra-Low Voltage 15-GHz Band Best FoM <-190 dBc/Hz LC-VCO ICs with Novel Harmonic Tuned LC Tank in 45-nm SOI CMOS

    Xiao XU  Tsuyoshi SUGIURA  Toshihiko YOSHIMASU  

     
    PAPER

      Vol:
    E102-C No:10
      Page(s):
    673-681

    This paper presents two ultra-low voltage and high performance VCO ICs with novel harmonic tuned LC tank which provides different harmonic impedance and shapes the pseudo-square drain voltage waveform of transistors. In the novel tank, two additional inductors are connected between the drains of the cross-coupled pMOSFETs and the conventional LC tank, and they effectively decrease second harmonic load impedance and increase third harmonic load impedance of the transistors. In this paper, the novel harmonic tuned LC tank is applied to two different structure VCOs. These two VCOs exhibit over 2 dB better phase noise performance than conventional LC tank VCOs among all tuning range. The conventional and proposed VCO ICs are designed, fabricated and measured on wafer in 45-nm SOI CMOS technology. With novel harmonic tuned LC tank, the novel two VCOs exhibit measured best phase-noise of -125.7 and -129.3 dBc/Hz at 10 MHz offset and related FoM of -190.2 and -190.5 dBc/Hz at a supply voltage of 0.3 V and 0.35 V, respectively. Frequency tuning range of the two VCOs are from 13.01 to 14.34 GHz and from 15.02 to 16.03GHz, respectively.

  • Reliability Analysis of Power and Communication Network in Drone Monitoring System

    Fengying MA  Yankai YIN  Wei CHEN  

     
    PAPER

      Pubricized:
    2019/05/02
      Vol:
    E102-B No:10
      Page(s):
    1991-1997

    The distinctive characteristics of unmanned aerial vehicle networks (UAVNs), including highly dynamic network topology, high mobility, and open-air wireless environments, may make UAVNs vulnerable to attacks and threats. Due to the special security requirements, researching in the high reliability of the power and communication network in drone monitoring system become special important. The reliability of the communication network and power in the drone monitoring system has been studied. In order to assess the reliability of the system power supply in the drone emergency monitoring system, the accelerated life tests under constant stress were presented based on the exponential distribution. Through a comparative analysis of lots of factors, the temperature was chosen as the constant accelerated stress parameter. With regard to the data statistical analysis, the type-I censoring sample method was put forward. The mathematical model of the drone monitoring power supply was established and the average life expectancy curve was obtained under different temperatures through the analysis of experimental data. The results demonstrated that the mathematical model and the average life expectancy curve were fit for the actual very well. With overall consideration of the communication network topology structure and network capacity the improved EED-SDP method was put forward in drone monitoring. It is concluded that reliability analysis of power and communication network in drone monitoring system is remarkably important to improve the reliability of drone monitoring system.

  • Data-Driven Decision-Making in Cyber-Physical Integrated Society

    Noboru SONEHARA  Takahisa SUZUKI  Akihisa KODATE  Toshihiko WAKAHARA  Yoshinori SAKAI  Yu ICHIFUJI  Hideo FUJII  Hideki YOSHII  

     
    INVITED PAPER

      Pubricized:
    2019/07/04
      Vol:
    E102-D No:9
      Page(s):
    1607-1616

    The Cyber-Physical Integrated Society (CPIS) is being formed with the fusion of cyber-space and the real-world. In this paper, we will discuss Data-Driven Decision-Making (DDDM) support systems to solve social problems in the CPIS. First, we introduce a Web of Resources (WoR) that uses Web booking log data for destination data management. Next, we introduce an Internet of Persons (IoP) system to visualize individual and group flows of people by analyzing collected Wi-Fi usage log data. Specifically, we present examples of how WoR and IoP visualize flows of groups of people that can be shared across different industries, including telecommunications carriers and railway operators, and policy decision support for local, short-term events. Finally, the importance of data-driven training of human resources to support DDDM in the future CPIS is discussed.

  • Vision Based Nighttime Vehicle Detection Using Adaptive Threshold and Multi-Class Classification

    Yuta SAKAGAWA  Kosuke NAKAJIMA  Gosuke OHASHI  

     
    PAPER

      Vol:
    E102-A No:9
      Page(s):
    1235-1245

    We propose a method that detects vehicles from in-vehicle monocular camera images captured during nighttime driving. Detecting vehicles from their shape is difficult at night; however, many vehicle detection methods focusing on light have been proposed. We detect bright spots by appropriate binarization based on the characteristics of vehicle lights such as brightness and color. Also, as the detected bright spots include lights other than vehicles, we need to distinguish the vehicle lights from other bright spots. Therefore, the bright spots were distinguished using Random Forest, a multiclass classification machine-learning algorithm. The features of bright spots not associated with vehicles were effectively utilized in the vehicle detection in our proposed method. More precisely vehicle detection is performed by giving weights to the results of the Random Forest based on the features of vehicle bright spots and the features of bright spots not related to the vehicle. Our proposed method was applied to nighttime images and confirmed effectiveness.

  • Fundamental Study on the Effects of Connector Torque Value on the Change of Inductance at the Contact Boundary

    Daisuke FUJIMOTO  Takashi NARIMATSU  Yu-ichi HAYASHI  

     
    PAPER

      Vol:
    E102-C No:9
      Page(s):
    636-640

    Under the condition of inadequate torque management, contact failure could occur in the interconnecting connector. Contact failure reduces the local immunity and degrades the electromagnetic properties of the equipment. It has been shown in previous reports that connector contact failure causes the parasitic inductance and radiated electromagnetic noise to increase. However, there is not enough discussion about the effects of connector torque fluctuation on the surrounding electromagnetic environment. Thus, in this study, the effects of a changing connector torque value on the circuit response and near field at the contact boundary were investigated. Based on these results, we discuss the influence of torque fluctuation on the electromagnetic environment surrounding the connector.

  • Acute Constraints in Straight-Line Drawings of Planar Graphs

    Akane SETO  Aleksandar SHURBEVSKI  Hiroshi NAGAMOCHI  Peter EADES  

     
    PAPER-Graph algorithms

      Vol:
    E102-A No:9
      Page(s):
    994-1001

    Recent research on graph drawing focuses on Right-Angle-Crossing (RAC) drawings of 1-plane graphs, where each edge is drawn as a straight line and two crossing edges only intersect at right angles. We give a transformation from a restricted case of the RAC drawing problem to a problem of finding a straight-line drawing of a maximal plane graph where some angles are required to be acute. For a restricted version of the latter problem, we show necessary and sufficient conditions for such a drawing to exist, and design an O(n2)-time algorithm that given an n-vertex plane graph produces a desired drawing of the graph or reports that none exists.

  • Dual Polarized Cylindrical Loop Slot Antenna for Omni Cell Application

    Bakar ROHANI  Ryosuke KANEDA  Hiroyuki ARAI  

     
    PAPER-Antennas and Propagation

      Pubricized:
    2019/02/12
      Vol:
    E102-B No:8
      Page(s):
    1668-1675

    Urban area suffers severe multipath effects due to its complex infrastructure environment and sector antenna is a popular choice as a base station antenna in those areas. Within sector antennas, omni cell antenna is utilized as supporting antenna to cover low reception areas between them. This paper proposes a slant 45° dual polarized omnidirectional antenna to operate as the omni cell antenna in those environments. The frequency band covers the IMT band, ranging from 1920MHz to 2170MHz with directivity focusing in horizontal plane. The antenna structure consists of a loop slot antenna array as excitation element which is placed inside a cylindrical slot antenna as parasitic element. Good performance is achieved in both S-parameter and directivity results, with a gain of more than 4 dBi and a gain difference of less than 1.5dB. The measurement results also agree well with the simulation results and the final design confirms that the proposed antenna works effectively as a slant ±45 ° dual polarized omnidirectional antenna.

  • Implementation of Smart Dressing Systems Based on Flexible pH Sensors Using PET Films

    Seok-Oh YUN  Jung Hoon LEE  Jin LEE  Choul-Young KIM  

     
    LETTER-Computer System

      Pubricized:
    2019/04/23
      Vol:
    E102-D No:8
      Page(s):
    1572-1575

    In this paper, a smart dressing system was implemented based on flexible pH sensors that can monitor the infection of a wounded area by tracking the pH value of the area. Motivated by the fabrication process widely used for semiconductors, the flexible pH sensor fabrication process was devised with a polyester (PET) film and a Si wafer, which deposits Au and Ag on a PET film. Because the electrodes are comprised of a working electrode and a reference electrode, the reference electrode was fabricated by synthesizing the Polyaniline (PANI) on Ag/AgCl, while the pH sensor has four channels to evenly measure the pH value in a wide area. The smart dressing system was constructed with four pH sensors, a single temperature sensor, a level shifter, a regulator, an analog-to-digital converter (ADC), and a monitoring PC. The measurement results show that our smart dressing system has a size of 5×5cm2 and can monitor the pH value range found in [3,9] with a sensitivity slope of 50mV/pH.

  • Channel Estimation and Achievable Rate of Massive MU-MIMO Systems with IQ Imbalance Open Access

    Nana ZHANG  Huarui YIN  Weidong WANG  Suhua TANG  

     
    PAPER

      Pubricized:
    2019/02/20
      Vol:
    E102-B No:8
      Page(s):
    1512-1525

    In-phase and quadrature-phase imbalance (IQI) at transceivers is one of the serious hardware impairments degrading system performance. In this paper, we study the overall performance of massive multi-user multi-input multi-output (MU-MIMO) systems with IQI at both the base station (BS) and user equipments (UEs), including the estimation of channel state information, required at the BS for the precoding design. We also adopt a widely-linear precoding based on the real-valued channel model to make better use of the image components of the received signal created by IQI. Of particular importance, we propose estimators of the real-valued channel and derive the closed-form expression of the achievable downlink rate. Both the analytical and simulation results show that IQI at the UEs limits the dowlink rate to finite ceilings even when an infinite number of BS antennas is available, and the results also prove that the widely-linear precoding based on the proposed channel estimation method can improve the overall performance of massive MU-MIMO systems with IQI.

  • Analysis of Modulated Terahertz Wave Radiation Characteristics in a Monolithic Integrated Structure Consisting of a Resonant Tunneling Diodes, a Photodiodes and a Self-Complementary Bow-Tie Antenna

    Masataka NAKANISHI  Michihiko SUHARA  Kiyoto ASAKAWA  

     
    BRIEF PAPER

      Vol:
    E102-C No:6
      Page(s):
    466-470

    We numerically demonstrate a possibility on-off keying (OOK) type of modulation over tens gigabits per second for sub-terahertz radiation in our proposed wireless transmitter device structure towards radio over fiber (RoF) technology. The integrated device consists of an InP-based compound semiconductor resonant tunneling diode (RTD) adjacent to an InP-based photo diode (PD), a self-complementary type of bow-tie antenna (BTA), external microstrip lines. These integration structures are carefully designed to obtain robust relaxation oscillation (RO) due to the negative differential conductance (NDC) characteristic of the RTD and the nonlinearity of the NDC. Moreover, the device is designed to exhibit OOK modulation of RO due to photo current from the PD inject into the RTD. Electromagnetic simulations and nonlinear equivalent circuit model of the whole device structure are established to perform large signal analysis numerically with considerations of previously measured characteristics of the triple-barrier RTD.

121-140hit(1315hit)