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  • Unconditionally Secure Broadcast Encryption Schemes with Trade-Offs between Communication and Storage

    Yohei WATANABE  Junji SHIKATA  

     
    PAPER

      Vol:
    E99-A No:6
      Page(s):
    1097-1106

    An (≤n,≤ω)-one-time secure broadcast encryption scheme (BES) allows a sender to choose any subset of receivers so that only the designated users can decrypt a ciphertext. In this paper, we first show an efficient construction of an (≤n,≤ω)-one-time secure BES with general ciphertext sizes. Specifically, we propose a generic construction of an (≤n,≤ω)-one-time secure BES from key predistribution systems (KPSs) when its ciphertext size is equal to integer multiple of the plaintext size, and our construction includes all known constructions. However, there are many possible combinations of the KPSs to realize the BES in our construction methodology, and therefore, we show that which combination is the best one in the sense that secret-key size can be minimized. Our (optimized) construction provides a flexible parameter setup (i.e. we can adjust the secret-key sizes) by setting arbitrary ciphertext sizes based on restrictions on channels such as channel capacity and channel bandwidth.

  • Adaptive Perceptual Block Compressive Sensing for Image Compression

    Jin XU  Yuansong QIAO  Zhizhong FU  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2016/03/09
      Vol:
    E99-D No:6
      Page(s):
    1702-1706

    Because the perceptual compressive sensing framework can achieve a much better performance than the legacy compressive sensing framework, it is very promising for the compressive sensing based image compression system. In this paper, we propose an innovative adaptive perceptual block compressive sensing scheme. Firstly, a new block-based statistical metric which can more appropriately measure each block's sparsity and perceptual sensibility is devised. Then, the approximated theoretical minimum measurement number for each block is derived from the new block-based metric and used as weight for adaptive measurements allocation. The obtained experimental results show that our scheme can significantly enhance both objective and subjective performance of a perceptual compressive sensing framework.

  • Sentence Similarity Computational Model Based on Information Content

    Hao WU  Heyan HUANG  

     
    PAPER-Natural Language Processing

      Pubricized:
    2016/03/14
      Vol:
    E99-D No:6
      Page(s):
    1645-1652

    Sentence similarity computation is an increasingly important task in applications of natural language processing such as information retrieval, machine translation, text summarization and so on. From the viewpoint of information theory, the essential attribute of natural language is that the carrier of information and the capacity of information can be measured by information content which is already successfully used for word similarity computation in simple ways. Existing sentence similarity methods don't emphasize the information contained by the sentence, and the complicated models they employ often need using empirical parameters or training parameters. This paper presents a fully unsupervised computational model of sentence semantic similarity. It is also a simply and straightforward model that neither needs any empirical parameter nor rely on other NLP tools. The method can obtain state-of-the-art experimental results which show that sentence similarity evaluated by the model is closer to human judgment than multiple competing baselines. The paper also tests the proposed model on the influence of external corpus, the performance of various sizes of the semantic net, and the relationship between efficiency and accuracy.

  • Predicting Performance of Collaborative Storytelling Using Multimodal Analysis

    Shogo OKADA  Mi HANG  Katsumi NITTA  

     
    PAPER

      Pubricized:
    2016/04/01
      Vol:
    E99-D No:6
      Page(s):
    1462-1473

    This study focuses on modeling the storytelling performance of the participants in a group conversation. Storytelling performance is one of the fundamental communication techniques for providing information and entertainment effectively to a listener. We present a multimodal analysis of the storytelling performance in a group conversation, as evaluated by external observers. A new multimodal data corpus is collected through this group storytelling task, which includes the participants' performance scores. We extract multimodal (verbal and nonverbal) features regarding storytellers and listeners from a manual description of spoken dialog and from various nonverbal patterns, including each participant's speaking turn, utterance prosody, head gesture, hand gesture, and head direction. We also extract multimodal co-occurrence features, such as head gestures, and interaction features, such as storyteller utterance overlapped with listener's backchannel. In the experiment, we modeled the relationship between the performance indices and the multimodal features using machine-learning techniques. Experimental results show that the highest accuracy (R2) is 0.299 for the total storytelling performance (sum of indices scores) obtained with a combination of verbal and nonverbal features in a regression task.

  • Layout-Conscious Expandable Topology for Low-Degree Interconnection Networks

    Thao-Nguyen TRUONG  Khanh-Van NGUYEN  Ikki FUJIWARA  Michihiro KOIBUCHI  

     
    PAPER-Computer System

      Pubricized:
    2016/02/02
      Vol:
    E99-D No:5
      Page(s):
    1275-1284

    System expandability becomes a major concern for highly parallel computers and data centers, because their number of nodes gradually increases year by year. In this context we propose a low-degree topology and its floor layout in which a cabinet or node set can be newly inserted by connecting short cables to a single existing cabinet. Our graph analysis shows that the proposed topology has low diameter, low average shortest path length and short average cable length comparable to existing topologies with the same degree. When incrementally adding nodes and cabinets to the proposed topology, its diameter and average shortest path length increase modestly. Our discrete-event simulation results show that the proposed topology provides a comparable performance to 2-D Torus for some parallel applications. The network cost and power consumption of DSN-F modestly increase when compared to the counterpart non-random topologies.

  • Adaptive Directional Lifting Structure of Three Dimensional Non-Separable Discrete Wavelet Transform for High Resolution Volumetric Data Compression

    Fairoza Amira BINTI HAMZAH  Taichi YOSHIDA  Masahiro IWAHASHI  Hitoshi KIYA  

     
    PAPER-Digital Signal Processing

      Vol:
    E99-A No:5
      Page(s):
    892-899

    As three dimensional (3D) discrete wavelet transform (DWT) is widely used for high resolution volumetric data compression, and to further improve the performance of lossless coding, the adaptive directional lifting (ADL) structure based on non-separable 3D DWT with a (5,3) filter is proposed in this paper. The proposed 3D DWT has less lifting steps and better prediction performance compared to the existing separable 3D DWT with fixed filter coefficients. It also has compatibility with the conventional DWT defined by the JPEG2000 international standard. The proposed method shows comparable and better results with the non-separable 3D DWT and separable 3D DWT and it is effective for lossless coding of high resolution volumetric data.

  • Real-Time Streaming Data Delivery over Named Data Networking Open Access

    Peter GUSEV  Zhehao WANG  Jeff BURKE  Lixia ZHANG  Takahiro YONEDA  Ryota OHNISHI  Eiichi MURAMOTO  

     
    INVITED PAPER

      Vol:
    E99-B No:5
      Page(s):
    974-991

    Named Data Networking (NDN) is a proposed future Internet architecture that shifts the fundamental abstraction of the network from host-to-host communication to request-response for named, signed data-an information dissemination focused approach. This paper describes a general design for receiver-driven, real-time streaming data (RTSD) applications over the current NDN implementation that aims to take advantage of the architecture's unique affordances. It is based on experimental development and testing of running code for real-time video conferencing, a positional tracking system for interactive multimedia, and a distributed control system for live performance. The design includes initial approaches to minimizing latency, managing buffer size and Interest retransmission, and adapting retrieval to maximize bandwidth and control congestion. Initial implementations of these approaches are evaluated for functionality and performance results, and the potential for future research in this area, and improved performance as new features of the architecture become available, is discussed.

  • A Distributed Capability Access Control Scheme in Information-Centric Networking

    Jung-Hwan CHA  Youn-Hee HAN  Sung-Gi MIN  

     
    PAPER-Network

      Vol:
    E99-B No:5
      Page(s):
    1121-1130

    Enforcing access control policies in Information-Centric Networking (ICN) is difficult due to there being multiple copies of contents in various network locations. Traditional Access Control List (ACL)-based schemes are ill-suited for ICN, because all potential content distribution servers should have an identical access control policy or they should contact a centralized ACL server whenever their contents are accessed by consumers. To address these problems, we propose a distributed capability access control scheme for ICN. The proposed scheme is composed of an internal capability and an external capability. The former is included in the content and the latter is added to a request message sent from the consumer. The content distribution servers can validate the access right of the consumer through the internal and external capabilities without contacting access control policies. The proposed model also enhances the privacy of consumers by keeping the content name and consumer identification anonymous. The performance analysis and implementation show that the proposed scheme is feasible and more efficient than other access control schemes.

  • Self Optimization Beam-Forming Null Control Based SINR Improvement

    Modick BASNET  Jeich MAR  

     
    PAPER-Measurement Technology

      Vol:
    E99-A No:5
      Page(s):
    963-972

    In this paper, a self optimization beamforming null control (SOBNC) scheme is proposed. There is a need of maintaining signal to interference plus noise ratio (SINR) threshold to control modulation and coding schemes (MCS) in recent technologies like Wi-Fi, Long Term Evolution (LTE) and Long Term Evolution Advanced (LTE-A). Selection of MCS depends on the SINR threshold that allows maintaining key performance index (KPI) like block error rate (BLER), bit error rate (BER) and throughput at certain level. The SOBNC is used to control the antenna pattern for SINR estimation and improve the SINR performance of the wireless communication systems. The nulling comes with a price; if wider nulls are introduced, i.e. more number of nulls are used, the 3dB beam-width and peak side lobe level (SLL) in antenna pattern changes critically. This paper proposes a method which automatically controls the number of nulls in the antenna pattern as per the changing environment based on adaptive-network based fuzzy interference system (ANFIS) to maintain output SINR level higher or equal to the required threshold. Finally, simulation results show a performance superiority of the proposed SOBNC compared with minimum mean square error (MMSE) based adaptive nulling control algorithm and conventional fixed null scheme.

  • Performance Analysis of Two-Way Relaying Network with Adaptive Modulation in the Presence of Imperfect Channel Information

    Kyu-Sung HWANG  MinChul JU  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:5
      Page(s):
    1170-1179

    In this paper, we study the impact of imperfect channel information on an amplify-and-forward (AF)-based two-way relaying network (TWRN) with adaptive modulation which consists of two end-terminals and multiple relays. Specifically, we consider a single-relay selection scheme of the TWRN in the presence of outdated channel state information (CSI) and channel estimation errors. First, we choose the best relay based on outdated CSI, and perform adaptive modulation on both relaying paths with channel estimation errors. Then, we discuss the impact of the outdated CSI on the statistics of the signal-to-noise ratio (SNR) per hop. In addition, we formulate the end-to-end SNRs with channel estimation errors and offer statistic analyses in the presence of both the outdated CSI and channel estimation errors. Finally, we provide the performance analyses of the proposed TWRN with adaptive modulation in terms of average spectral efficiency, average bit error rate, and outage probability. Numerical examples are given to verify our obtained analytical results for various system conditions.

  • A New Class of Hilbert Pairs of Almost Symmetric Orthogonal Wavelet Bases

    Daiwei WANG  Xi ZHANG  

     
    PAPER-Digital Signal Processing

      Vol:
    E99-A No:5
      Page(s):
    884-891

    This paper proposes a new class of Hilbert pairs of almost symmetric orthogonal wavelet bases. For two wavelet bases to form a Hilbert pair, the corresponding scaling lowpass filters are required to satisfy the half-sample delay condition. In this paper, we design simultaneously two scaling lowpass filters with the arbitrarily specified flat group delay responses at ω=0, which satisfy the half-sample delay condition. In addition to specifying the number of vanishing moments, we apply the Remez exchange algorithm to minimize the difference of frequency responses between two scaling lowpass filters, in order to improve the analyticity of complex wavelets. The equiripple behavior of the error function can be obtained through a few iterations. Therefore, the resulting complex wavelets are orthogonal and almost symmetric, and have the improved analyticity. Finally, some examples are presented to demonstrate the effectiveness of the proposed design method.

  • SSL Client Authentication with TPM

    Shohei KAKEI  Masami MOHRI  Yoshiaki SHIRAISHI  Masakatu MORII  

     
    PAPER

      Pubricized:
    2016/01/28
      Vol:
    E99-D No:4
      Page(s):
    1052-1061

    TPM-embedded devices can be used as authentication tokens by issuing certificates to signing keys generated by TPM. TPM generates Attestation Identity Key (AIK) and Binding Key (BK) that are RSA keys. AIK is used to identify TPM. BK is used to encrypt data so that specific TPM can decrypt it. TPM can use for device authentication by linking a SSL client certificate to TPM. This paper proposes a method of an AIK certificate issuance with OpenID and a method of the SSL client certificate issuance to specific TPM using AIK and BK. In addition, the paper shows how to implement device authentication system using the SSL client certificate related to TPM.

  • A Healthcare Information System for Secure Delivery and Remote Management of Medical Records

    Hyoung-Kee CHOI  Ki-Eun SHIN  Hyoungshick KIM  

     
    PAPER-Privacy protection in information systems

      Pubricized:
    2016/01/13
      Vol:
    E99-D No:4
      Page(s):
    883-890

    With the rapid merger of healthcare business and information technology, more healthcare institutions and medical practices are sharing information. Since these records often contain patients' sensitive personal information, Healthcare Information Systems (HISs) should be properly designed to manage these records in a secure manner. We propose a novel security design for the HIS complying with the security and privacy rules. The proposed system defines protocols to ensure secure delivery of medical records over insecure public networks and reliable management of medical record in the remote server without incurring excessive costs to implement services for security. We demonstrate the practicality of the proposed system through a security analysis and performance evaluation.

  • Efficient Algorithm for Math Formula Semantic Search

    Shunsuke OHASHI  Giovanni Yoko KRISTIANTO  Goran TOPIC  Akiko AIZAWA  

     
    PAPER

      Pubricized:
    2016/01/14
      Vol:
    E99-D No:4
      Page(s):
    979-988

    Mathematical formulae play an important role in many scientific domains. Regardless of the importance of mathematical formula search, conventional keyword-based retrieval methods are not sufficient for searching mathematical formulae, which are structured as trees. The increasing number as well as the structural complexity of mathematical formulae in scientific articles lead to the necessity for large-scale structure-aware formula search techniques. In this paper, we formulate three types of measures that represent distinctive features of semantic similarity of math formulae, and develop efficient hash-based algorithms for the approximate calculation. Our experiments using NTCIR-11 Math-2 Task dataset, a large-scale test collection for math information retrieval with about 60-million formulae, show that the proposed method improves the search precision while also keeps the scalability and runtime efficiency high.

  • Object Tracking with Embedded Deformable Parts in Dynamic Conditional Random Fields

    Suofei ZHANG  Zhixin SUN  Xu CHENG  Lin ZHOU  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2016/01/19
      Vol:
    E99-D No:4
      Page(s):
    1268-1271

    This work presents an object tracking framework which is based on integration of Deformable Part based Models (DPMs) and Dynamic Conditional Random Fields (DCRF). In this framework, we propose a DCRF based novel way to track an object and its details on multiple resolutions simultaneously. Meanwhile, we tackle drastic variations in target appearance such as pose, view, scale and illumination changes with DPMs. To embed DPMs into DCRF, we design specific temporal potential functions between vertices by explicitly formulating deformation and partial occlusion respectively. Furthermore, temporal transition functions between mixture models bring higher robustness to perspective and pose changes. To evaluate the efficacy of our proposed method, quantitative tests on six challenging video sequences are conducted and the results are analyzed. Experimental results indicate that the method effectively addresses serious problems in object tracking and performs favorably against state-of-the-art trackers.

  • Novel Reconfigurable Hardware Accelerator for Protein Sequence Alignment Using Smith-Waterman Algorithm

    Atef IBRAHIM  Hamed ELSIMARY  Abdullah ALJUMAH  

     
    PAPER-Digital Signal Processing

      Vol:
    E99-A No:3
      Page(s):
    683-690

    This paper presents novel reconfigurable semi-systolic array architecture for the Smith-Waterman with an affine gap penalty algorithm to align protein sequences optimized for shorter database sequences. This architecture has been modified to enable hardware reuse rather than replicating processing elements of the semi-systolic array in multiple FPGAs. The proposed hardware architecture and the previously published conventional one are described at the Register Transfer Level (RTL) using VHDL language and implemented using the FPGA technology. The results show that the proposed design has significant higher normalized speedup (up to 125%) over the conventional one for query sequence lengths less than 512 residues. According to the UniProtKB/TrEMBL protein database (release 2015_05) statistics, the largest number of sequences (about 80%) have sequence length less than 512 residues that makes the proposed design outperforms the conventional one in terms of speed and area in this sequence lengths range.

  • Time Performance Optimization and Resource Conflicts Resolution for Multiple Project Management

    Cong LIU  Jiujun CHENG  Yirui WANG  Shangce GAO  

     
    PAPER-Software Engineering

      Pubricized:
    2015/12/04
      Vol:
    E99-D No:3
      Page(s):
    650-660

    Time performance optimization and resource conflict resolution are two important challenges in multiple project management contexts. Compared with traditional project management, multi-project management usually suffers limited and insufficient resources, and a tight and urgent deadline to finish all concurrent projects. In this case, time performance optimization of the global project management is badly needed. To our best knowledge, existing work seldom pays attention to the formal modeling and analyzing of multi-project management in an effort to eliminate resource conflicts and optimizing the project execution time. This work proposes such a method based on PRT-Net, which is a Petri net-based formulism tailored for a kind of project constrained by resource and time. The detailed modeling approaches based on PRT-Net are first presented. Then, resource conflict detection method with corresponding algorithm is proposed. Next, the priority criteria including a key-activity priority strategy and a waiting-short priority strategy are presented to resolve resource conflicts. Finally, we show how to construct a conflict-free PRT-Net by designing resource conflict resolution controllers. By experiments, we prove that our proposed priority strategy can ensure the execution time of global multiple projects much shorter than those without using any strategies.

  • Closed-Form Approximations for Gaussian Sum Smoother with Nonlinear Model

    Haiming DU  Jinfeng CHEN  Huadong WANG  

     
    PAPER-Digital Signal Processing

      Vol:
    E99-A No:3
      Page(s):
    691-701

    Research into closed-form Gaussian sum smoother has provided an attractive approach for tracking in clutter, joint detection and tracking (in clutter), and multiple target tracking (in clutter) via the probability hypothesis density (PHD). However, Gaussian sum smoother with nonlinear target model has particular nonlinear expressions in the backward smoothed density that are different from the other filters and smoothers. In order to extend the closed-form solution of linear Gaussian sum smoother to nonlinear model, two closed-form approximations for nonlinear Gaussian sum smoother are proposed, which use Gaussian particle approximation and unscented transformation approximation, separately. Since the estimated target number of PHD smoother is not stable, a heuristic approximation method is added. At last, the Bernoulli smoother and PHD smoother are simulated using Gaussian particle approximation and unscented transformation approximation, and simulation results show that the two proposed algorithms can obtain smoothed tracks with nonlinear models, and have better performance than filter.

  • An Efficient Selection Method of a Transmitted OFDM Signal Sequence for Various SLM Schemes

    Kee-Hoon KIM  Hyun-Seung JOO  Jong-Seon NO  Dong-Joon SHIN  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:3
      Page(s):
    703-713

    Many selected mapping (SLM) schemes have been proposed to reduce the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signal sequences. In this paper, an efficient selection (ES) method of the OFDM signal sequence with minimum PAPR among many alternative OFDM signal sequences is proposed; it supports various SLM schemes. Utilizing the fact that OFDM signal components can be sequentially generated in many SLM schemes, the generation and PAPR observation of the OFDM signal sequence are processed concurrently. While the u-th alternative OFDM signal components are being generated, by applying the proposed ES method, the generation of that alternative OFDM signal components can be interrupted (or stopped) according to the selection criteria of the best OFDM signal sequence in the considered SLM scheme. Such interruption substantially reduces the average computational complexity of SLM schemes without degradation of PAPR reduction performance, which is confirmed by analytical and numerical results. Note that the proposed method is not an isolated SLM scheme but a subsidiary method which can be easily adopted in many SLM schemes in order to further reduce the computational complexity of considered SLM schemes.

  • Decoding of Projective Reed-Muller Codes by Dividing a Projective Space into Affine Spaces

    Norihiro NAKASHIMA  Hajime MATSUI  

     
    PAPER-Coding Theory

      Vol:
    E99-A No:3
      Page(s):
    733-741

    A projective Reed-Muller (PRM) code, obtained by modifying a Reed-Muller code with respect to a projective space, is a doubly extended Reed-Solomon code when the dimension of the related projective space is equal to 1. The minimum distance and the dual code of a PRM code are known, and some decoding examples have been presented for low-dimensional projective spaces. In this study, we construct a decoding algorithm for all PRM codes by dividing a projective space into a union of affine spaces. In addition, we determine the computational complexity and the number of correctable errors of our algorithm. Finally, we compare the codeword error rate of our algorithm with that of the minimum distance decoding.

641-660hit(3161hit)