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  • An Overview of Security and Privacy Issues for Internet of Things Open Access

    Heung Youl YOUM  

     
    INVITED PAPER

      Pubricized:
    2017/05/18
      Vol:
    E100-D No:8
      Page(s):
    1649-1662

    The Internet of Things (IoT) is defined as a global infrastructure for the Information Society, enabling advanced services by interconnecting (physical and virtual) things based on, existing and evolving, interoperable information and communication technologies by ITU-T. Data may be communicated in low-power and lossy environments, which causes complicated security issues. Furthermore, concerns are raised over access of personally identifiable information pertaining to IoT devices, network and platforms. Security and privacy concerns have been main barriers to implement IoT, which needs to be resolved appropriate security and privacy measures. This paper describes security threats and privacy concerns of IoT, surveys current studies related to IoT and identifies the various requirements and solutions to address these security threats and privacy concerns. In addition, this paper also focuses on major global standardization activities for security and privacy of Internet of Things. Furthermore, future directions and strategies of international standardization for theInternet of Thing's security and privacy issues will be given. This paper provides guidelines to assist in suggesting the development and standardization strategies forward to allow a massive deployment of IoT systems in real world.

  • Demonstration of Three-Dimensional Near-Field Beamforming by Planar Loop Array for Magnetic Resonance Wireless Power Transfer

    Bo-Hee CHOI  Jeong-Hae LEE  

     
    PAPER-Antennas and Propagation

      Pubricized:
    2017/01/24
      Vol:
    E100-B No:8
      Page(s):
    1449-1453

    This paper presents a capacitor-loaded 4x4 planar loop array for three-dimensional near-field beamforming of magnetic resonance wireless power transfer (WPT). This planar loop array provides three important functions: beamforming, selective power transfer, and the ability to work alignment free with the receiver. These functions are realized by adjusting the capacitance of each loop. The optimal capacitance of each loop that corresponds to the three functions can be found using a genetic algorithm (GA); the three functions were verified by comparing simulations and measurements at a frequency of 6.78MHz. Finally, the beamforming mechanism of a near-field loop array was investigated using the relationship between the current magnitude and the resonance frequency of each loop, resulting in the findings that the magnitude and the resonance frequency are correlated. This focused current of the specified loop creates a strong magnetic field in front of that loop, resulting in near-field beamforming.

  • Kernel CCA Based Transfer Learning for Software Defect Prediction

    Ying MA  Shunzhi ZHU  Yumin CHEN  Jingjing LI  

     
    LETTER-Software Engineering

      Pubricized:
    2017/04/28
      Vol:
    E100-D No:8
      Page(s):
    1903-1906

    An transfer learning method, called Kernel Canonical Correlation Analysis plus (KCCA+), is proposed for heterogeneous Cross-company defect prediction. Combining the kernel method and transfer learning techniques, this method improves the performance of the predictor with more adaptive ability in nonlinearly separable scenarios. Experiments validate its effectiveness.

  • Variable Tap-Length NLMS Algorithm with Adaptive Parameter

    Yufei HAN  Mingjiang WANG  Boya ZHAO  

     
    LETTER-Digital Signal Processing

      Vol:
    E100-A No:8
      Page(s):
    1720-1723

    Improved fractional variable tap-length adaptive algorithm that contains Sigmoid limited fluctuation function and adaptive variable step-size of tap-length based on fragment-full error is presented. The proposed algorithm can solve many deficiencies in previous algorithm, comprising small convergence rate and weak anti-interference ability. The parameters are able to modify reasonably on the basis of different situations. The Sigmoid constrained function can decrease the fluctuant amplitude of the instantaneous errors effectively and improves the ability of anti-noise interference. Simulations demonstrate that the proposed algorithm equips better performance.

  • Stochastic Fault-Tolerant Routing in Dual-Cubes

    Junsuk PARK  Nobuhiro SEKI  Keiichi KANEKO  

     
    LETTER-Dependable Computing

      Pubricized:
    2017/05/10
      Vol:
    E100-D No:8
      Page(s):
    1920-1921

    In the topologies for interconnected nodes, it is desirable to have a low degree and a small diameter. For the same number of nodes, a dual-cube topology has almost half the degree compared to a hypercube while increasing the diameter by just one. Hence, it is a promising topology for interconnection networks of massively parallel systems. We propose here a stochastic fault-tolerant routing algorithm to find a non-faulty path from a source node to a destination node in a dual-cube.

  • Radio Resource Management Based on User and Network Characteristics Considering 5G Radio Access Network in a Metropolitan Environment

    Akira KISHIDA  Yoshifumi MORIHIRO  Takahiro ASAI  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Pubricized:
    2017/02/08
      Vol:
    E100-B No:8
      Page(s):
    1352-1365

    In this paper, we clarify the issues in a metropolitan environment involving overlying frequency bands with various bandwidths and propose a cell selection scheme that improves the communications quality based on user and network characteristics. Different frequency bands with various signal bandwidths will be overlaid on each other in forthcoming fifth-generation (5G) radio access networks. At the same time, services, applications or features of sets of user equipment (UEs) will become more diversified and the requirements for the quality of communications will become more varied. Moreover, in real environments, roads and buildings have irregular constructions. Especially in an urban or metropolitan environment, the complex architecture present in a metropolis directly affects radio propagation. Under these conditions, the communications quality is degraded because cell radio resources are depleted due to many UE connections and the mismatch between service requirements and cell capabilities. The proposed scheme prevents this degradation in communications quality. The effectiveness of the proposed scheme is evaluated in an ideal regular deployment and in a non-regular metropolitan environment based on computer simulations. Simulation results show that the average of the time for the proposed scheme from the start of transmission to the completion of reception at the UE is improved by approximately 40% compared to an existing cell selection scheme that is based on the Maximum Signal-to-Interference plus Noise power Ratio (SINR).

  • A Balanced Decision Tree Based Heuristic for Linear Decomposition of Index Generation Functions

    Shinobu NAGAYAMA  Tsutomu SASAO  Jon T. BUTLER  

     
    PAPER-Logic Design

      Pubricized:
    2017/05/19
      Vol:
    E100-D No:8
      Page(s):
    1583-1591

    Index generation functions model content-addressable memory, and are useful in virus detectors and routers. Linear decompositions yield simpler circuits that realize index generation functions. This paper proposes a balanced decision tree based heuristic to efficiently design linear decompositions for index generation functions. The proposed heuristic finds a good linear decomposition of an index generation function by using appropriate cost functions and a constraint to construct a balanced tree. Since the proposed heuristic is fast and requires a small amount of memory, it is applicable even to large index generation functions that cannot be solved in a reasonable time by existing heuristics. This paper shows time and space complexities of the proposed heuristic, and experimental results using some large examples to show its efficiency.

  • A Fast Updatable Implementation of Index Generation Functions Using Multiple IGUs

    Tsutomu SASAO  

     
    PAPER-Logic Design

      Pubricized:
    2017/05/19
      Vol:
    E100-D No:8
      Page(s):
    1574-1582

    This paper presents a method to realize index generation functions using multiple Index Generation Units (IGUs). The architecture implements index generation functions more efficiently than a single IGU when the number of registered vectors is very large. This paper proves that independent linear transformations are necessary in IGUs for efficient realization. Experimental results confirm this statement. Finally, it shows a fast update method to IGUs.

  • Pre-Processing for Fine-Grained Image Classification

    Hao GE  Feng YANG  Xiaoguang TU  Mei XIE  Zheng MA  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2017/05/12
      Vol:
    E100-D No:8
      Page(s):
    1938-1942

    Recently, numerous methods have been proposed to tackle the problem of fine-grained image classification. However, rare of them focus on the pre-processing step of image alignment. In this paper, we propose a new pre-processing method with the aim of reducing the variance of objects among the same class. As a result, the variance of objects between different classes will be more significant. The proposed approach consists of four procedures. The “parts” of the objects are firstly located. After that, the rotation angle and the bounding box could be obtained based on the spatial relationship of the “parts”. Finally, all the images are resized to similar sizes. The objects in the images possess the properties of translation, scale and rotation invariance after processed by the proposed method. Experiments on the CUB-200-2011 and CUB-200-2010 datasets have demonstrated that the proposed method could boost the recognition performance by serving as a pre-processing step of several popular classification algorithms.

  • An Approach for Chinese-Japanese Named Entity Equivalents Extraction Using Inductive Learning and Hanzi-Kanji Mapping Table

    JinAn XU  Yufeng CHEN  Kuang RU  Yujie ZHANG  Kenji ARAKI  

     
    PAPER-Natural Language Processing

      Pubricized:
    2017/05/02
      Vol:
    E100-D No:8
      Page(s):
    1882-1892

    Named Entity Translation Equivalents extraction plays a critical role in machine translation (MT) and cross language information retrieval (CLIR). Traditional methods are often based on large-scale parallel or comparable corpora. However, the applicability of these studies is constrained, mainly because of the scarcity of parallel corpora of the required scale, especially for language pairs of Chinese and Japanese. In this paper, we propose a method considering the characteristics of Chinese and Japanese to automatically extract the Chinese-Japanese Named Entity (NE) translation equivalents based on inductive learning (IL) from monolingual corpora. The method adopts the Chinese Hanzi and Japanese Kanji Mapping Table (HKMT) to calculate the similarity of the NE instances between Japanese and Chinese. Then, we use IL to obtain partial translation rules for NEs by extracting the different parts from high similarity NE instances in Chinese and Japanese. In the end, the feedback processing updates the Chinese and Japanese NE entity similarity and rule sets. Experimental results show that our simple, efficient method, which overcomes the insufficiency of the traditional methods, which are severely dependent on bilingual resource. Compared with other methods, our method combines the language features of Chinese and Japanese with IL for automatically extracting NE pairs. Our use of a weak correlation bilingual text sets and minimal additional knowledge to extract NE pairs effectively reduces the cost of building the corpus and the need for additional knowledge. Our method may help to build a large-scale Chinese-Japanese NE translation dictionary using monolingual corpora.

  • Leveraging Compressive Sensing for Multiple Target Localization and Power Estimation in Wireless Sensor Networks

    Peng QIAN  Yan GUO  Ning LI  Baoming SUN  

     
    PAPER-Network

      Pubricized:
    2017/02/09
      Vol:
    E100-B No:8
      Page(s):
    1428-1435

    The compressive sensing (CS) theory has been recognized as a promising technique to achieve the target localization in wireless sensor networks. However, most of the existing works require the prior knowledge of transmitting powers of targets, which is not conformed to the case that the information of targets is completely unknown. To address such a problem, in this paper, we propose a novel CS-based approach for multiple target localization and power estimation. It is achieved by formulating the locations and transmitting powers of targets as a sparse vector in the discrete spatial domain and the received signal strengths (RSSs) of targets are taken to recover the sparse vector. The key point of CS-based localization is the sensing matrix, which is constructed by collecting RSSs from RF emitters in our approach, avoiding the disadvantage of using the radio propagation model. Moreover, since the collection of RSSs to construct the sensing matrix is tedious and time-consuming, we propose a CS-based method for reconstructing the sensing matrix from only a small number of RSS measurements. It is achieved by exploiting the CS theory and designing an difference matrix to reveal the sparsity of the sensing matrix. Finally, simulation results demonstrate the effectiveness and robustness of our localization and power estimation approach.

  • Calculation of Lightning-Induced Voltages on Overhead Lines from Oblique Return Stroke Channel above Stratified Lossy Ground in Time Domain

    Xiaojia WANG  Yazhou CHEN  Haojiang WAN  Qingxi YANG  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Pubricized:
    2017/02/17
      Vol:
    E100-B No:8
      Page(s):
    1454-1461

    In this paper, the effect of the tilt angle of return stroke channel and the stratified lossy ground on the lightning-induced voltages on the overhead lines are studied using the modified transmission-line model with linear current decay with height (MTLL). The results show that the lightning-induced voltages from oblique discharge channel are larger than those from the vertical discharge channel, and the peak values of the induced voltages will increase with increasing the tilt angle. When the ground is horizontally stratified, the peak of the induced voltages will increase with increasing the conductivity of the lower layer at different distances. When the upper ground conductivity increases, the voltage peak values will decrease if the overhead line is nearby the lightning strike point and increase if the overhead line is far from the lightning strike point. Moreover, the induced voltages are mainly affected by the conductivity of the lower layer soil when the conductivity of the upper layer ground is smaller than that of the lower layer ground at far distances. When the ground is vertically stratified, the induced voltages are mainly affected by the conductivity of the ground near the strike point when the overhead line and the strike point are located above the same medium; if the overhead line and the strike point are located above different mediums, both of the conductivities of the vertically stratified ground will influence the peak of the induced voltages and the conductivity of the ground which is far from the strike point has much more impact on induced voltages.

  • Relation Extraction with Deep Reinforcement Learning

    Hongjun ZHANG  Yuntian FENG  Wenning HAO  Gang CHEN  Dawei JIN  

     
    PAPER-Natural Language Processing

      Pubricized:
    2017/05/17
      Vol:
    E100-D No:8
      Page(s):
    1893-1902

    In recent years, deep learning has been widely applied in relation extraction task. The method uses only word embeddings as network input, and can model relations between target named entity pairs. It equally deals with each relation mention, so it cannot effectively extract relations from the corpus with an enormous number of non-relations, which is the main reason why the performance of relation extraction is significantly lower than that of relation classification. This paper designs a deep reinforcement learning framework for relation extraction, which considers relation extraction task as a two-step decision-making game. The method models relation mentions with CNN and Tree-LSTM, which can calculate initial state and transition state for the game respectively. In addition, we can tackle the problem of unbalanced corpus by designing penalty function which can increase the penalties for first-step decision-making errors. Finally, we use Q-Learning algorithm with value function approximation to learn control policy π for the game. This paper sets up a series of experiments in ACE2005 corpus, which show that the deep reinforcement learning framework can achieve state-of-the-art performance in relation extraction task.

  • Trajectory-Set Feature for Action Recognition

    Kenji MATSUI  Toru TAMAKI  Bisser RAYTCHEV  Kazufumi KANEDA  

     
    LETTER-Pattern Recognition

      Pubricized:
    2017/05/10
      Vol:
    E100-D No:8
      Page(s):
    1922-1924

    We propose a feature for action recognition called Trajectory-Set (TS), on top of the improved Dense Trajectory (iDT). The TS feature encodes only trajectories around densely sampled interest points, without any appearance features. Experimental results on the UCF50 action dataset demonstrates that TS is comparable to state-of-the-arts, and outperforms iDT; the accuracy of 95.0%, compared to 91.7% by iDT.

  • A Novel RNN-GBRBM Based Feature Decoder for Anomaly Detection Technology in Industrial Control Network

    Hua ZHANG  Shixiang ZHU  Xiao MA  Jun ZHAO  Zeng SHOU  

     
    PAPER-Industrial Control System Security

      Pubricized:
    2017/05/18
      Vol:
    E100-D No:8
      Page(s):
    1780-1789

    As advances in networking technology help to connect industrial control networks with the Internet, the threat from spammers, attackers and criminal enterprises has also grown accordingly. However, traditional Network Intrusion Detection System makes significant use of pattern matching to identify malicious behaviors and have bad performance on detecting zero-day exploits in which a new attack is employed. In this paper, a novel method of anomaly detection in industrial control network is proposed based on RNN-GBRBM feature decoder. The method employ network packets and extract high-quality features from raw features which is selected manually. A modified RNN-RBM is trained using the normal traffic in order to learn feature patterns of the normal network behaviors. Then the test traffic is analyzed against the learned normal feature pattern by using osPCA to measure the extent to which the test traffic resembles the learned feature pattern. Moreover, we design a semi-supervised incremental updating algorithm in order to improve the performance of the model continuously. Experiments show that our method is more efficient in anomaly detection than other traditional approaches for industrial control network.

  • Low-Complexity Hybrid Precoding Design for MIMO-OFDM Millimeter Wave Communications

    Yue DONG  Chen CHEN  Na YI  Shijian GAO  Ye JIN  

     
    PAPER-Wireless Communication Technologies

      Pubricized:
    2017/02/08
      Vol:
    E100-B No:8
      Page(s):
    1228-1237

    Hybrid analog/digital precoding has attracted growing attention for millimeter wave (mmWave) communications, since it can support multi-stream data transmission with limited hardware cost. A main challenge in implementing hybrid precoding is that the channels will exhibit frequency-selective fading due to the large bandwidth. To this end, we propose a practical hybrid precoding scheme with finite-resolution phase shifters by leveraging the correlation among the subchannels. Furthermore, we utilize the sparse feature of the mmWave channels to design a low-complexity algorithm to realize the proposed hybrid precoding, which can avoid the complication of the high-dimensionality eigenvalue decomposition. Simulation results show that the proposed hybrid precoding can approach the performance of unconstrained fully-digital precoding but with low hardware cost and computational complexity.

  • Feature Selection Based on Modified Bat Algorithm

    Bin YANG  Yuliang LU  Kailong ZHU  Guozheng YANG  Jingwei LIU  Haibo YIN  

     
    PAPER-Pattern Recognition

      Pubricized:
    2017/05/01
      Vol:
    E100-D No:8
      Page(s):
    1860-1869

    The rapid development of information techniques has lead to more and more high-dimensional datasets, making classification more difficult. However, not all of the features are useful for classification, and some of these features may even cause low classification accuracy. Feature selection is a useful technique, which aims to reduce the dimensionality of datasets, for solving classification problems. In this paper, we propose a modified bat algorithm (BA) for feature selection, called MBAFS, using a SVM. Some mechanisms are designed for avoiding the premature convergence. On the one hand, in order to maintain the diversity of bats, they are guided by the combination of a random bat and the global best bat. On the other hand, to enhance the ability of escaping from local optimization, MBAFS employs one mutation mechanism while the algorithm trapped into local optima. Furthermore, the performance of MBAFS was tested on twelve benchmark datasets, and was compared with other BA based algorithms and some well-known BPSO based algorithms. Experimental results indicated that the proposed algorithm outperforms than other methods. Also, the comparison details showed that MBAFS is competitive in terms of computational time.

  • Node-to-Node Disjoint Paths Problem in Möbius Cubes

    David KOCIK  Keiichi KANEKO  

     
    PAPER-Dependable Computing

      Pubricized:
    2017/04/25
      Vol:
    E100-D No:8
      Page(s):
    1837-1843

    The Möbius cube is a variant of the hypercube. Its advantage is that it can connect the same number of nodes as a hypercube but with almost half the diameter of the hypercube. We propose an algorithm to solve the node-to-node disjoint paths problem in n-Möbius cubes in polynomial-order time of n. We provide a proof of correctness of the algorithm and estimate that the time complexity is O(n2) and the maximum path length is 3n-5.

  • Fine-Grained Analysis of Compromised Websites with Redirection Graphs and JavaScript Traces

    Yuta TAKATA  Mitsuaki AKIYAMA  Takeshi YAGI  Takeshi YADA  Shigeki GOTO  

     
    PAPER-Internet Security

      Pubricized:
    2017/05/18
      Vol:
    E100-D No:8
      Page(s):
    1714-1728

    An incident response organization such as a CSIRT contributes to preventing the spread of malware infection by analyzing compromised websites and sending abuse reports with detected URLs to webmasters. However, these abuse reports with only URLs are not sufficient to clean up the websites. In addition, it is difficult to analyze malicious websites across different client environments because these websites change behavior depending on a client environment. To expedite compromised website clean-up, it is important to provide fine-grained information such as malicious URL relations, the precise position of compromised web content, and the target range of client environments. In this paper, we propose a new method of constructing a redirection graph with context, such as which web content redirects to malicious websites. The proposed method analyzes a website in a multi-client environment to identify which client environment is exposed to threats. We evaluated our system using crawling datasets of approximately 2,000 compromised websites. The result shows that our system successfully identified malicious URL relations and compromised web content, and the number of URLs and the amount of web content to be analyzed were sufficient for incident responders by 15.0% and 0.8%, respectively. Furthermore, it can also identify the target range of client environments in 30.4% of websites and a vulnerability that has been used in malicious websites by leveraging target information. This fine-grained analysis by our system would contribute to improving the daily work of incident responders.

  • Iterative Reduction of Out-of-Band Power and Peak-to-Average Power Ratio for Non-Contiguous OFDM Systems Based on POCS

    Yanqing LIU  Liang DONG  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Pubricized:
    2017/02/17
      Vol:
    E100-B No:8
      Page(s):
    1489-1497

    Non-contiguous orthogonal frequency-division multiplexing (OFDM) is a promising technique for cognitive radio systems. The secondary users transmit on the selected subcarriers to avoid the frequencies being used by the primary users. However, the out-of-band power (OBP) of the OFDM-modulated tones induces interference to the primary users. Another major drawback of OFDM-based system is their high peak-to-average power ratio (PAPR). In this paper, algorithms are proposed to jointly reduce the OBP and the PAPR for non-contiguous OFDM based on the method of alternating projections onto convex sets. Several OFDM subcarriers are selected to accommodate the adjusting weights for OBP and PAPR reduction. The frequency-domain OFDM symbol is projected onto two convex sets that are defined according to the OBP requirements and the PAPR limits. Each projection iteration solves a convex optimization problem. The projection onto the set constrained by the OBP requirement can be calculated using an iterative algorithm which has low computational complexity. Simulation results show good performance of joint reduction of the OBP and the PAPR. The proposed algorithms converge quickly in a few iterations.

1461-1480hit(8214hit)