The search functionality is under construction.
The search functionality is under construction.

Keyword Search Result

[Keyword] (42807hit)

3721-3740hit(42807hit)

  • Comprehensive Survey of IPv6 Transition Technologies: A Subjective Classification for Security Analysis

    Gábor LENCSE  Youki KADOBAYASHI  

     
    SURVEY PAPER-Internet

      Pubricized:
    2019/04/08
      Vol:
    E102-B No:10
      Page(s):
    2021-2035

    Due to the depletion of the public IPv4 address pool, the transition to IPv6 became inevitable. However, this ongoing transition is taking a long time, and the two incompatible versions of the Internet Protocol must coexist. Different IPv6 transition technologies were developed, which can be used to enable communication in various scenarios, but they also involve additional security issues. In this paper, first, we introduce our methodology for analyzing the security of IPv6 transition technologies in a nutshell. Then, we develop a priority classification method for the ranking of different IPv6 transition technologies and their most important implementations, so that the vulnerabilities of the most crucial ones may be examined first. Next, we conduct a comprehensive survey of the existing IPv6 transition technologies by describing their application scenarios and the basics of their operation and we also determine the priorities of their security analysis according to our ranking system. Finally, we show that those IPv6 transition technologies that we gave high priorities, cover the most relevant scenarios.

  • 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.

  • 60GHz 180µW Power Consumption CMOS ASK Transmitter Using Combined On-Chip Resonator and Antenna

    Mizuki MOTOYOSHI  Suguru KAMEDA  Noriharu SUEMATSU  

     
    PAPER

      Vol:
    E102-C No:10
      Page(s):
    725-731

    In this paper, we proposed low power consumption ASK transmitter based on the direct modulated oscillator at 60GHz-band. To achieve the proposed transmitter, high power-efficient oscillator and loss less modulator are designed. Moreover combined on-chip resonator and antenna to remove the buffer amplifier of the transmitter to reduce the power consumption and size. The proposed transmitter has been fabricated in standard 65nm CMOS process. The core area is 1130µm×590µm with pads. The operation frequency is 60.4GHz. The BER of 10-6 is achieved under 50Mbps with power consumption of less than 260µW including the buffer amplifier. Using the proposed combined on-chip resonator and antenna, which need no buffer amplifier for transmitter and the power consumption is reduced to 180µW.

  • Effectiveness of Speech Mode Adaptation for Improving Dialogue Speech Synthesis

    Kazuki KAYA  Hiroki MORI  

     
    LETTER-Speech and Hearing

      Pubricized:
    2019/06/13
      Vol:
    E102-D No:10
      Page(s):
    2064-2066

    The effectiveness of model adaptation in dialogue speech synthesis is explored. The proposed adaptation method is based on a conversion from a base model learned with a large dataset into a target, dialogue-style speech model. The proposed method is shown to improve the intelligibility of synthesized dialogue speech, while maintaining the speaking style of dialogue.

  • Automatic Lung Nodule Detection in CT Images Using Convolutional Neural Networks

    Furqan SHAUKAT  Kamran JAVED  Gulistan RAJA  Junaid MIR  Muhammad Laiq Ur Rahman SHAHID  

     
    PAPER-Image

      Vol:
    E102-A No:10
      Page(s):
    1364-1373

    One of the major causes of mortalities around the globe is lung cancer with the least chance of survival even after the diagnosis. Computer-aided detection can play an important role, especially in initial screening and thus prevent the deaths caused by lung cancer. In this paper, a novel technique for lung nodule detection, which is the primary cause of lung cancer, is proposed using convolutional neural networks. Initially, the lung volume is segmented from a CT image using optimal thresholding which is followed by image enhancement using multi-scale dot enhancement filtering. Next, lung nodule candidates are detected from an enhanced image and certain features are extracted. The extracted features belong to intensity, shape and texture class. Finally, the classification of lung nodule candidates into nodules and non-nodules is done using a convolutional neural network. The Lung Image Database Consortium (LIDC) dataset has been used to evaluate the proposed system which achieved an accuracy of 94.80% with 6.2 false positives per scan only.

  • GaN Amplifiers of Selectable Output Power Function with Semi-Custom Matching Networks

    Yutaro YAMAGUCHI  Masatake HANGAI  Shintaro SHINJO  Takaaki YOSHIOKA  Naoki KOSAKA  

     
    PAPER

      Vol:
    E102-C No:10
      Page(s):
    682-690

    A methodology for obtaining semi-custom high-power amplifiers (HPAs) is described. The semi-custom concept pertains to the notion that a selectable output power is attainable by replacing only transistors. To compensate for the mismatch loss, a new output matching network that can be easily tuned by wiring is proposed. Design equations were derived to determine the circuit parameters and specify the bandwidth limitations. To verify this methodology, a semi-custom HPA with GaN HEMTs was fabricated in the S-band. A selectable output power from 240 to 150 W was successfully achieved while maintaining a PAE of over 50% in a 19% relative bandwidth.

  • Theoretical Analysis and Experimental Verification on High-Isolation Surface-Acoustic-Wave Duplexer with On-Chip Compensation Circuit

    Masafumi IWAKI  Masanori UEDA  Yoshio SATOH  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E102-C No:10
      Page(s):
    748-755

    This paper describes the theoretical analysis and experimental verification of a new type high-isolation surface-acoustic-wave (SAW) duplexer by using a SAW on-chip compensation circuit designed to cancel the signal of the main SAW filter at an attenuation frequency band. First, a numerical analysis based on the interference of waves propagating parallel waveguides is applied to clarify the relation between the absolute improvement value of the filter's attenuation level and cancel conditions. Then, the feasibility of the SAW compensation circuit using the double mode SAW (DMS) resonator filter are studied in both a circuit simulation and experiment. As a result, a 10-30 dB attenuation improvement was achieved within a band range of several tens of MHz using electrical characteristics of the lower side slope in the DMS resonator filter, and that it agrees well with the result obtained by numerical analysis. These results are expected to be useful for current and future mobile systems wants higher receiver sensitivity.

  • Hardware-Based Principal Component Analysis for Hybrid Neural Network Trained by Particle Swarm Optimization on a Chip

    Tuan Linh DANG  Yukinobu HOSHINO  

     
    PAPER-Neural Networks and Bioengineering

      Vol:
    E102-A No:10
      Page(s):
    1374-1382

    This paper presents a hybrid architecture for a neural network (NN) trained by a particle swarm optimization (PSO) algorithm. The NN is implemented on the hardware side while the PSO is executed by a processor on the software side. In addition, principal component analysis (PCA) is also applied to reduce correlated information. The PCA module is implemented in hardware by the SystemVerilog programming language to increase operating speed. Experimental results showed that the proposed architecture had been successfully implemented. In addition, the hardware-based NN trained by PSO (NN-PSO) program was faster than the software-based NN trained by the PSO program. The proposed NN-PSO with PCA also obtained better recognition rates than the NN-PSO without-PCA.

  • Enhancing the Performance of Cuckoo Search Algorithm with Multi-Learning Strategies Open Access

    Li HUANG  Xiao ZHENG  Shuai DING  Zhi LIU  Jun HUANG  

     
    PAPER-Fundamentals of Information Systems

      Pubricized:
    2019/07/09
      Vol:
    E102-D No:10
      Page(s):
    1916-1924

    The Cuckoo Search (CS) is apt to be trapped in local optimum relating to complex target functions. This drawback has been recognized as the bottleneck of its widespread use. This paper, with the purpose of improving CS, puts forward a Cuckoo Search algorithm featuring Multi-Learning Strategies (LSCS). In LSCS, the Converted Learning Module, which features the Comprehensive Learning Strategy and Optimal Learning Strategy, tries to make a coordinated cooperation between exploration and exploitation, and the switching in this part is decided by the transition probability Pc. When the nest fails to be renewed after m iterations, the Elite Learning Perturbation Module provides extra diversity for the current nest, and it can avoid stagnation. The Boundary Handling Approach adjusted by Gauss map is utilized to reset the location of nest beyond the boundary. The proposed algorithm is evaluated by two different tests: Test Group A(ten simple unimodal and multimodal functions) and Test Group B(the CEC2013 test suite). Experiments results show that LSCS demonstrates significant advantages in terms of convergence speed and optimization capability in solving complex problems.

  • LEF: An Effective Routing Algorithm for Two-Dimensional Meshes

    Thiem Van CHU  Kenji KISE  

     
    PAPER-Computer System

      Pubricized:
    2019/07/09
      Vol:
    E102-D No:10
      Page(s):
    1925-1941

    We design a new oblivious routing algorithm for two-dimensional mesh-based Networks-on-Chip (NoCs) called LEF (Long Edge First) which offers high throughput with low design complexity. LEF's basic idea comes from conventional wisdom in choosing the appropriate dimension-order routing (DOR) algorithm for supercomputers with asymmetric mesh or torus interconnects: routing longest dimensions first provides better performance than other strategies. In LEF, we combine the XY DOR and the YX DOR. When routing a packet, which DOR algorithm is chosen depends on the relative position between the source node and the destination node. Decisions of selecting the appropriate DOR algorithm are not fixed to the network shape but instead made on a per-packet basis. We also propose an efficient deadlock avoidance method for LEF in which the use of virtual channels is more flexible than in the conventional method. We evaluate LEF against O1TURN, another effective oblivious routing algorithm, and a minimal adaptive routing algorithm based on the odd-even turn model. The evaluation results show that LEF is particularly effective when the communication is within an asymmetric mesh. In a 16×8 NoC, LEF even outperforms the adaptive routing algorithm in some cases and delivers from around 4% up to around 64.5% higher throughput than O1TURN. Our results also show that the proposed deadlock avoidance method helps to improve LEF's performance significantly and can be used to improve O1TURN's performance. We also examine LEF in large-scale NoCs with thousands of nodes. Our results show that, as the NoC size increases, the performance of the routing algorithms becomes more strongly influenced by the resource allocation policy in the network and the effect is different for each algorithm. This is evident in that results of middle-scale NoCs with around 100 nodes cannot be applied directly to large-scale NoCs.

  • LGCN: Learnable Gabor Convolution Network for Human Gender Recognition in the Wild Open Access

    Peng CHEN  Weijun LI  Linjun SUN  Xin NING  Lina YU  Liping ZHANG  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2019/06/13
      Vol:
    E102-D No:10
      Page(s):
    2067-2071

    Human gender recognition in the wild is a challenging task due to complex face variations, such as poses, lighting, occlusions, etc. In this letter, learnable Gabor convolutional network (LGCN), a new neural network computing framework for gender recognition was proposed. In LGCN, a learnable Gabor filter (LGF) is introduced and combined with the convolutional neural network (CNN). Specifically, the proposed framework is constructed by replacing some first layer convolutional kernels of a standard CNN with LGFs. Here, LGFs learn intrinsic parameters by using standard back propagation method, so that the values of those parameters are no longer fixed by experience as traditional methods, but can be modified by self-learning automatically. In addition, the performance of LGCN in gender recognition is further improved by applying a proposed feature combination strategy. The experimental results demonstrate that, compared to the standard CNNs with identical network architecture, our approach achieves better performance on three challenging public datasets without introducing any sacrifice in parameter size.

  • FOREWORD Open Access

    Atsushi SANADA  

     
    FOREWORD

      Vol:
    E102-C No:10
      Page(s):
    658-658
  • 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.

  • Quantifying Dynamic Leakage - Complexity Analysis and Model Counting-based Calculation - Open Access

    Bao Trung CHU  Kenji HASHIMOTO  Hiroyuki SEKI  

     
    PAPER-Software System

      Pubricized:
    2019/07/11
      Vol:
    E102-D No:10
      Page(s):
    1952-1965

    A program is non-interferent if it leaks no secret information to an observable output. However, non-interference is too strict in many practical cases and quantitative information flow (QIF) has been proposed and studied in depth. Originally, QIF is defined as the average of leakage amount of secret information over all executions of a program. However, a vulnerable program that has executions leaking the whole secret but has the small average leakage could be considered as secure. This counter-intuition raises a need for a new definition of information leakage of a particular run, i.e., dynamic leakage. As discussed in [5], entropy-based definitions do not work well for quantifying information leakage dynamically; Belief-based definition on the other hand is appropriate for deterministic programs, however, it is not appropriate for probabilistic ones.In this paper, we propose new simple notions of dynamic leakage based on entropy which are compatible with existing QIF definitions for deterministic programs, and yet reasonable for probabilistic programs in the sense of [5]. We also investigated the complexity of computing the proposed dynamic leakage for three classes of Boolean programs. We also implemented a tool for QIF calculation using model counting tools for Boolean formulae. Experimental results on popular benchmarks of QIF research show the flexibility of our framework. Finally, we discuss the improvement of performance and scalability of the proposed method as well as an extension to more general cases.

  • RF-Drone: Multi-Tag System for RF-ID Enables Drone Tracking in GPS-Denied Environments

    Xiang LU  Ziyang CHEN  Lianpo WANG  Ruidong LI  Chao ZHAI  

     
    PAPER

      Pubricized:
    2019/04/26
      Vol:
    E102-B No:10
      Page(s):
    1941-1950

    In resent years, providing location services for mobile targets in a closed environment has been a growing interest. In order to provide good localization and tracking performance for drones in GPS-denied scenarios, this paper proposes a multi-tag radio frequency identification (RFID) system that is easy to equip and does not take up the limited resources of the drone which is not susceptible to processor performance and cost constraints compared with computer vision based approaches. The passive RFID tags, no battery equipped, have an ultra-high resolution of millimeter level. We attach multiple tags to the drone and form multiple sets of virtual antenna arrays during motion, avoiding arranging redundant antennas in applications, and calibrating the speed chain to improve tracking performance. After combining the strap-down inertial navigation system (SINS) carried by the drone, we have established a coupled integration model that can suppress the drift error of SINS with time. The experiment was designed in bi-dimensional and three-dimensional scenarios, and the integrated positioning system based on SINS/RFID was evaluated. Finally, we discussed the impact of some parameters, this innovative approach is verified in real scenarios.

  • 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.

  • Phase-Based Periocular Recognition with Texture Enhancement Open Access

    Luis Rafael MARVAL-PÉREZ  Koichi ITO  Takafumi AOKI  

     
    PAPER-Image

      Vol:
    E102-A No:10
      Page(s):
    1351-1363

    Access control and surveillance applications like walking-through security gates and immigration control points have a great demand for convenient and accurate biometric recognition in unconstrained scenarios with low user cooperation. The periocular region, which is a relatively new biometric trait, has been attracting much attention for recognition of an individual in such scenarios. This paper proposes a periocular recognition method that combines Phase-Based Correspondence Matching (PB-CM) with a texture enhancement technique. PB-CM has demonstrated high recognition performance in other biometric traits, e.g., face, palmprint and finger-knuckle-print. However, a major limitation for periocular region is that the performance of PB-CM degrades when the periocular skin has poor texture. We address this problem by applying texture enhancement and found out that variance normalization of texture significantly improves the performance of periocular recognition using PB-CM. Experimental evaluation using three public databases demonstrates the advantage of the proposed method compared with conventional methods.

  • High Efficiency Class-E and Compact Doherty Power Amplifiers with Novel Harmonics Termination for Handset Applications

    Tsuyoshi SUGIURA  Satoshi FURUTA  Tadamasa MURAKAMI  Koki TANJI  Norihisa OTANI  Toshihiko YOSHIMASU  

     
    PAPER

      Vol:
    E102-C No:10
      Page(s):
    699-706

    This paper presents high efficiency Class-E and compact Doherty power amplifiers (PAs) with novel harmonics termination for handset applications using a GaAs/InGaP heterojunction bipolar transistor (HBT) process. The novel harmonics termination circuit effectively reduces the insertion loss of the matching circuit, allowing a device with a compact size. The Doherty PA uses a lumped-element transformer which consists of metal-insulator-metal (MIM) capacitors on an IC substrate, a bonding-wire inductor and short micro-strip lines on a printed circuit board (PCB). The fabricated Class-E PA exhibits a power added efficiency (PAE) as high as 69.0% at 1.95GHz and as high as 67.6% at 2.535GHz. The fabricated Doherty PA exhibits an average output power of 25.5dBm and a PAE as high as 50.1% under a 10-MHz band width quadrature phase shift keying (QPSK) 6.16-dB peak-to-average-power-ratio (PAPR) LTE signal at 1.95GHz. The fabricated chip size is smaller than 1mm2. The input and output Doherty transformer areas are 0.5mm by 1.0mm and 0.7mm by 0.7mm, respectively.

  • Design of a Wideband Constant-on-Time Control Envelope Amplifier for Wireless Basestation Envelope Tracking Power Amplifiers

    Deng-Fong LU  Chin HSIA  

     
    PAPER

      Vol:
    E102-C No:10
      Page(s):
    707-716

    Envelope tracking (ET) technology provides the potential for achieving high efficiency in power amplifiers (PAs) with high peak-to-average ratio (PAR) signals. Envelope amplifiers with high fidelity, high efficiency, and wide bandwidth are critical components for the widespread application of envelope tracking. This paper presents the design of a linear-assisted switching buck converter for use in an envelope amplifier. To effectively leverage the high efficiency of buck converters and the wide bandwidth capabilities of linear amplifiers, a parallel combination of these two devices is employed in this work. A novel current-sense constant-on-time (COT) controller is proposed to coordinate this hybrid power supply. The combination mainly enables the switching converter to provide the average power required by the PA with high efficiency, while the wideband linear amplifier provides a wide range of dynamic voltages. The technique improves the efficiency of the envelope amplifier, especially for applications requiring high PAR with wider bandwidth signals. Measurement of the envelope amplifier showed an efficiency of approximately 77% with 10 W output power using LTE downlink signals. The overall ET system was demonstrated by using a GaN PA. The measured average power-added efficiency of the amplifier reached above 45% for an LTE modulated signal with 20 MHz bandwidth and PAR of 8.0 dB, at an average output power of 5 W and gain of 10.1 dB. The measured normalized RMS error is below 2.1% with adjacent channel leakage ratio of -48 dBc at an offset frequency of 20 MHz.

  • QoS-Constrained Robust Beamforming Design for MIMO Interference Channels with Bounded CSI Errors Open Access

    Conggai LI  Xuan GENG  Feng LIU  

     
    LETTER-Communication Theory and Signals

      Vol:
    E102-A No:10
      Page(s):
    1426-1430

    Constrained by quality-of-service (QoS), a robust transceiver design is proposed for multiple-input multiple-output (MIMO) interference channels with imperfect channel state information (CSI) under bounded error model. The QoS measurement is represented as the signal-to-interference-plus-noise ratio (SINR) for each user with single data stream. The problem is formulated as sum power minimization to reduce the total power consumption for energy efficiency. In a centralized manner, alternating optimization is performed at each node. For fixed transmitters, closed-form expression for the receive beamforming vectors is deduced. And for fixed receivers, the sum-power minimization problem is recast as a semi-definite program form with linear matrix inequalities constraints. Simulation results demonstrate the convergence and robustness of the proposed algorithm, which is important for practical applications in future wireless networks.

3721-3740hit(42807hit)