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11501-11520hit(42807hit)

  • Proportionally Quasi-Fair Scheduling for End-to-End Rates in Multi-Hop Wireless Networks

    Dang-Quang BUI  Won-Joo HWANG  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E96-B No:3
      Page(s):
    820-829

    Known an a criterion that solves the trade-off between fairness and efficiency, proportional fairness is well-studied in cellular networks in the Qualcomm High Data Rate System. In multi-hop wireless networks, proportional fairness is solved by maximizing the logarithmic aggregate utility function. However, this approach can deal with instantaneous rates only where long term fairness is to be targeted. In this case, cumulative rates are more suitable. This paper proposes a framework for multi-hop wireless networks to guarantee fairness of cumulative data rates. The framework can be extended to other kinds of fairness such as max-min fairness, and to more complex networks, multi-channel multi-radio wireless networks.

  • Transform Domain Shadow Removal for Foreground Silhouette

    Toshiaki SHIOTA  Kazuki NAKAGAMI  Takao NISHITANI  

     
    PAPER-Digital Signal Processing

      Vol:
    E96-A No:3
      Page(s):
    667-674

    A novel shadow removal approach is proposed by using block-wise transform domain shadow detection. The approach is based on the fact that the spatial frequency distributions on normal background areas and those under casted shadows from foreground objects are the same. The proposed approach is especially useful for silhouette extraction by using the Gaussian Mixture background Model (GMM) foreground segmentation in the transform domain, because the frequency distribution has already been calculated in the foreground segmentation. The stable shadow removal is realized, due to the transform domain implementation.

  • Correlation Power Analysis and Countermeasure on the Stream Cipher Enocoro-128v2

    Shugo MIKAMI  Hirotaka YOSHIDA  Dai WATANABE  Kazuo SAKIYAMA  

     
    PAPER-Cryptography and Information Security

      Vol:
    E96-A No:3
      Page(s):
    697-704

    Enocoro-128v2 is a lightweight stream cipher submitted to Cryptography Research and Evaluation Committees (CRYPTREC). In this paper, we first describe a side channel attack on Enocoro-128v2. We show that all secret key bytes of Enocoro-128v2 can be recovered by correlation power analysis, and it is shown by an experiment that around 6000 traces are needed to recover the secret key on SASEBO-GII (Side-channel Attack Standard Evaluation Board). We second propose a countermeasure with threshold implementation technique, which allows Enocoro-128v2 to be resistant against correlation power analysis as long as less than 105 traces are used.

  • Symbol-Rate Clock Recovery for Integrating DFE Receivers

    Tsutomu TAKEYA  Tadahiro KURODA  

     
    PAPER-Communication Theory and Signals

      Vol:
    E96-A No:3
      Page(s):
    705-712

    In this paper, a symbol-rate clock recovery scheme for a receiver that uses an integrating decision feedback equalizer (DFE) is proposed. The proposed clock recovery using expected received signal amplitudes as the criterion realizes minimum mean square error (MMSE) clock recovery. A receiver architecture using an integrating DFE with the proposed symbol-rate clock recovery is also proposed. The proposed clock recovery algorithm successfully recovered the clock phase in a system level simulation only with a DFE. Higher jitter tolerance than 0.26 UIPP at 10 Gb/s operation was also confirmed in the simulation with an 11 dB channel loss at 5 GHz.

  • On the Security of an Identity-Based Proxy Signature Scheme in the Standard Model

    Ying SUN  Yong YU  Xiaosong ZHANG  Jiwen CHAI  

     
    LETTER-Cryptography and Information Security

      Vol:
    E96-A No:3
      Page(s):
    721-723

    Observing the security of existing identity-based proxy signature schemes was proven in the random oracle model, Cao et al. proposed the first direct construction of identity-based proxy signature secure in the standard model by making use of the identity-based signature due to Paterson and Schuldt. They also provided a security proof to show their construction is secure against forgery attacks without resorting to the random oracles. Unfortunately, in this letter, we demonstrate that their scheme is vulnerable to insider attacks. Specifically, after a private-key extraction query, an adversary, behaving as a malicious original signer or a malicious proxy signer, is able to violate the unforgeability of the scheme.

  • Outage Capacity of Spectrum Sharing Cognitive Radio with MRC Diversity and Outdated CSI under Asymmetric Fading

    Ding XU  Zhiyong FENG  Ping ZHANG  

     
    LETTER-Communication Theory and Signals

      Vol:
    E96-A No:3
      Page(s):
    732-736

    Spectrum sharing cognitive radio (CR) with maximal ratio combining (MRC) diversity under asymmetric fading is studied. Specifically, the channel on the secondary transmitter (STx) to the secondary receiver (SRx) link is Nakagami-m distributed while the channel on the STx to the primary receiver (PRx) link is Rayleigh distributed, and the channel state information (CSI) on the STx-PRx link is assumed to be outdated due to feedback delay. The outage capacity of the secondary user (SU) is derived under the average interference and peak transmit power constraints. The results supported by simulations are presented and show the effects of various system parameters on the outage capacity. Particularly, it is shown that the outdated CSI has no impact on the outage capacities in the cases of low peak transmit power constraint and zero-outage probability. It is also shown that MRC diversity can significantly improve the outage capacity especially for the zero-outage capacity and the outage capacity under low outage probability.

  • Survey on Data Center Networking Technologies Open Access

    Yoshiaki KIRIHA  Motoo NISHIHARA  

     
    INVITED SURVEY PAPER

      Vol:
    E96-B No:3
      Page(s):
    713-721

    In recent years, technologies and markets related to data centers have been rapidly changing and growing. Data centers are playing an important role in ICT infrastructure deployment and promise to become common platforms for almost all social infrastructures. Even though research has focused on networking technologies, various technologies are needed to develop high-performance, cost-efficient, and flexible large-scale data centers. To understand those technologies better, this paper surveys recent research and development efforts and results in accordance with a data center network taxonomy that the authors defined.

  • Perceptual Distortion Measure for Polygon-Based Shape Coding

    Zhongyuan LAI  Wenyu LIU  Fan ZHANG  Guang CHENG  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E96-D No:3
      Page(s):
    750-753

    In this paper, we present a perceptual distortion measure (PDM) for polygon-based shape coding. We model the PDM as the salience of relevance triangle, and express the PDM by using three properties derived from the salience of visual part. Performance analysis and experimental results show that our proposal can improve the quality of the shape reconstruction when the object contour has sharp protrusions.

  • Path-Moose: A Scalable All-Path Bridging Protocol

    Guillermo IBÁÑEZ  Iván MARSÁ-MAESTRE  Miguel A. LOPEZ-CARMONA  Ignacio PÉREZ-IBÁÑEZ  Jun TANAKA  Jon CROWCROFT  

     
    PAPER-Network System

      Vol:
    E96-B No:3
      Page(s):
    756-763

    This paper describes Path-Moose, a scalable tree-based shortest path bridging protocol. Both ARP-Path and Path-Moose protocols belong to a new category of bridges that we name All-path, because all paths of the network are explored simultaneously with a broadcast frame distributed over all network links to find a path or set a multicast tree. Path-Moose employs the ARP-based low latency routing mechanism of the ARP-Path protocol on a bridge basis instead of a per-single-host basis. This increases scalability by reducing forwarding table entries at core bridges by a factor of fifteen times for big data center networks and achieves a faster reconfiguration by an approximate factor of ten. Reconfiguration time is significantly shorter than ARP-Path (zero in many cases) because, due to the sharing of network paths by the hosts connected to same edge bridges, when a host needs the path it has already been recovered by another user of the path. Evaluation through simulations shows protocol correctness and confirms the theoretical evaluation results.

  • Exact Algorithms for Annotated Edge Dominating Set in Graphs with Degree Bounded by 3

    Mingyu XIAO  Hiroshi NAGAMOCHI  

     
    PAPER

      Vol:
    E96-D No:3
      Page(s):
    408-418

    Given a graph G = (V,E) together with a nonnegative integer requirement on vertices r:V Z+, the annotated edge dominating set problem is to find a minimum set M ⊆ E such that, each edge in E - M is adjacent to some edge in M, and M contains at least r(v) edges incident on each vertex v ∈ V. The annotated edge dominating set problem is a natural extension of the classical edge dominating set problem, in which the requirement on vertices is zero. The edge dominating set problem is an important graph problem and has been extensively studied. It is well known that the problem is NP-hard, even when the graph is restricted to a planar or bipartite graph with maximum degree 3. In this paper, we show that the annotated edge dominating set problem in graphs with maximum degree 3 can be solved in O*(1.2721n) time and polynomial space, where n is the number of vertices in the graph. We also show that there is an O*(2.2306k)-time polynomial-space algorithm to decide whether a graph with maximum degree 3 has an annotated edge dominating set of size k or not.

  • Linear-Time Algorithm for the Length-Constrained Heaviest Path Problem in a Tree with Uniform Edge Lengths

    Sung Kwon KIM  

     
    LETTER

      Vol:
    E96-D No:3
      Page(s):
    498-501

    Given a tree T with edge lengths and edge weights, and a value B, the length-constrained heaviest path problem is to find a path in T with maximum path weight whose path length is at most B. We present a linear time algorithm for the problem when the edge lengths are uniform, i.e., all one. This algorithm with slight modification can be used to find the heaviest path of length exactly B in T in linear time.

  • Theoretical Study on the Reaction Mechanism of Formation of Lutidine Derivatives – Unexpected FLUORAL-P Compounds –

    Hiroyuki TERAMAE  Yasuko Y. MARUO  Jiro NAKAMURA  

     
    BRIEF PAPER

      Vol:
    E96-C No:3
      Page(s):
    383-384

    The reaction path from acetyl acetone (pentane-2,4-dione) to lutidine derivative is calculated at the HF/3-21G + ZPC level(ZPC=zero point energy correction), and MP2/6-31G(d,p) + ZPC level. As a model for porous glass, H2Si=O and (OH)2Si=O make chemical bonds or strong complex with FLUORAL-P that decrease the activation energy of a H2O elimination reaction.

  • An Improved Traffic Matrix Decomposition Method with Frequency-Domain Regularization

    Zhe WANG  Kai HU  Baolin YIN  

     
    LETTER-Information Network

      Vol:
    E96-D No:3
      Page(s):
    731-734

    We propose a novel network traffic matrix decomposition method named Stable Principal Component Pursuit with Frequency-Domain Regularization (SPCP-FDR), which improves the Stable Principal Component Pursuit (SPCP) method by using a frequency-domain noise regularization function. An experiment demonstrates the feasibility of this new decomposition method.

  • Improving User's Privacy for Multi-Authority ABE Using Privacy Homomorphism

    Ang GAO  Zeng-Zhi LI  

     
    LETTER-Cryptography and Information Security

      Vol:
    E96-A No:3
      Page(s):
    724-727

    In order to improve user's privacy in multi-authority Attribute-Based Encryption (ABE), we propose a solution which hides user's attributes by privacy homomorphism, such that not only the “external” adversary fails to access the private attribute of one user by eavesdropping on communications, but also the “internal” Attribute Authorities (AA), who are responsible for issuing attribute keys, are unable to build a full profile with all of the user's attributes by pooling their information on the user's ID. Meanwhile, the use of ID is essential to defend against collusion attack on ABE. Benefiting from privacy homomorphism, by which we distribute the part of the interpolation for the shares abstracted by the hidden attributes into each AA, the performance of the proposed scheme is higher than those of existing ABE schemes.

  • FOREWORD Open Access

    Shigeru AKAMATSU  

     
    FOREWORD

      Vol:
    E96-D No:3
      Page(s):
    506-506
  • Cross-Pose Face Recognition – A Virtual View Generation Approach Using Clustering Based LVTM

    Xi LI  Tomokazu TAKAHASHI  Daisuke DEGUCHI  Ichiro IDE  Hiroshi MURASE  

     
    PAPER-Face Perception and Recognition

      Vol:
    E96-D No:3
      Page(s):
    531-537

    This paper presents an approach for cross-pose face recognition by virtual view generation using an appearance clustering based local view transition model. Previously, the traditional global pattern based view transition model (VTM) method was extended to its local version called LVTM, which learns the linear transformation of pixel values between frontal and non-frontal image pairs from training images using partial image in a small region for each location, instead of transforming the entire image pattern. In this paper, we show that the accuracy of the appearance transition model and the recognition rate can be further improved by better exploiting the inherent linear relationship between frontal-nonfrontal face image patch pairs. This is achieved based on the observation that variations in appearance caused by pose are closely related to the corresponding 3D structure and intuitively frontal-nonfrontal patch pairs from more similar local 3D face structures should have a stronger linear relationship. Thus for each specific location, instead of learning a common transformation as in the LVTM, the corresponding local patches are first clustered based on an appearance similarity distance metric and then the transition models are learned separately for each cluster. In the testing stage, each local patch for the input non-frontal probe image is transformed using the learned local view transition model corresponding to the most visually similar cluster. The experimental results on a real-world face dataset demonstrated the superiority of the proposed method in terms of recognition rate.

  • Energy- and Traffic-Balance-Aware Mapping Algorithm for Network-on-Chip

    Zhi DENG  Huaxi GU  Yingtang YANG  Hua YOU  

     
    LETTER-Computer System

      Vol:
    E96-D No:3
      Page(s):
    719-722

    In this paper, an energy- and traffic-balance-aware mapping algorithm from IP cores to nodes in a network is proposed for application-specific Network-on-Chip(NoC). The multi-objective optimization model is set up by considering the NoC architecture, and addressed by the proposed mapping algorithm that decomposes mapping optimization into a number of scalar subproblems simultaneously. In order to show performance of the proposed algorithm, the application specific benchmark is applied in the simulation. The experimental results demonstrate that the algorithm has advantages in energy consumption and traffic balance over other algorithms.

  • A Low-Complexity Stopping Criterion for Turbo Decoding Using Forward State Metrics at a Single Time Instant

    Sun-Ting LIN  Shou-Sheu LIN  Je-An LAI  

     
    PAPER-Fundamental Theories for Communications

      Vol:
    E96-B No:3
      Page(s):
    722-729

    A stopping criterion is an indispensable function to reduce unnecessary power consumption and decoding delay in turbo decoding. Until now, a common design philosophy in previous works has involved using the entire block of information from the MAP decoder and its input/output information to calculate the stopping index. It is an intuitive method but suffers from heavy memory requirements and high calculation complexity. In this paper, a low-complexity stopping criterion is proposed that avoids the aforementioned disadvantages. A general abstraction model is utilized to analyze the design bottleneck of stopping criteria. Instead of using an entire block of information, a compact representation derived from the internal information of the MAP decoder at a single time instant is used as a low-complexity stopping index. Theoretical explanation is provided to justify the feasibility of the proposed criterion. Simulation results show that the proposed criterion can reduce the complexity of stopping criterion dramatically while continuing to achieve the same level of performance as previous works.

  • Design of the Start-Frame-Delimiter Pair for 802.15 Smart Utility Network System

    Liru LU  Hiroshi HARADA  Ryuhei FUNADA  Chin-Sean SUM  

     
    PAPER-Transmission Systems and Transmission Equipment for Communications

      Vol:
    E96-B No:3
      Page(s):
    730-736

    The Start-frame-delimiter (SFD) is crucial in packet-based communications system since it indicates the end of preamble and the start of a frame. In 802.15 smart utility network system, the function of SFD is extended. Two different SFDs are used for achieving frame synchronization and at the same time, to differentiate coded and uncoded packets. This paper proposes a systematic method for the selection of SFD pair for FSK based systems. The design method is adopted by 802.15.4g Task Group with the backward compatibility to IEEE 802.15.4d systems taken into account. Four selection criteria are specified and discussed to determine the pair of sequences providing least packet error detection rate with the consideration of eliminating the adjacent channel image signal commonly occurred in the low IF receiver. The probability of false alarm and miss detection is analyzed to verify the effectiveness of the proposed selection method. The simulation results confirm that error frame detection rate of 1e-3 can be achieved with selected SFD sequences. The proposed method for selection of SFD pairs ensures a robust packet header and thus better payload protection. The SFD design approach is applicable to other packet-based wireless communication FSK systems with the support of more than one SFD sequence.

  • RTSP-Based Adaptive Sending Control for IPTV Service in Heterogeneous Networks and Experimental Implementation

    Soohong PARK  Choong Seon HONG  

     
    LETTER-Internet

      Vol:
    E96-B No:3
      Page(s):
    905-909

    This letter proposes a new mechanism that supports adaptive sending control using Real-Time Streaming Protocol (RTSP) and Transmission Control Protocol (TCP) for IPTV service over heterogeneous networks. The proposed mechanism is implemented on a mobile IPTV device and its performance is verified for providing seamless television watching in heterogeneous networks, even when in motion.

11501-11520hit(42807hit)