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3461-3480hit(18690hit)

  • Fuzzy Commitment Scheme-Based Secure Identification for JPEG Images with Various Compression Ratios

    Kenta IIDA  Hitoshi KIYA  

     
    PAPER-Image

      Vol:
    E99-A No:11
      Page(s):
    1962-1970

    A secure identification scheme for JPEG images is proposed in this paper. The aim is to robustly identify JPEG images which are generated from the same original image under various compression levels in security. A property of the positive and negative signs of DCT coefficients is employed to achieve a robust scheme. The proposed scheme is robust against a difference in compression levels, and does not produce false negative matches in any compression level. Conventional schemes that have this property are not secure. To construct a secure identification system, we combine a new error correction technique with 1-bit parity with a fuzzy commitment scheme, which is a well-known biometric cryptosystem. In addition, a way for speeding up the identification is also proposed. The experimental results show the proposed scheme is effective for not only still images, but also video sequences in terms of the querying such as false positive, false negative and true positive matches, while keeping a high level of the security.

  • Improving Performance of Heuristic Algorithms by Lebesgue Spectrum Filter Open Access

    Mikio HASEGAWA  

     
    INVITED PAPER

      Vol:
    E99-B No:11
      Page(s):
    2256-2262

    The previous researches on the chaotic CDMA have theoretically derived the chaotic sequences having the minimum asynchronous cross-correlation. To minimize the asynchronous cross-correlation, autocorrelation of each sequence have to be C(τ)≈C×rτ, r=-2+√3, dumped oscillation with increase of the lag τ. There are several methods to generate such sequences, using a chaotic map, using the Lebesgue spectrum filter (LSF) and so on. In this paper, such lowest cross-correlation found in the chaotic CDMA researches is applied to solution search algorithms for combinatorial optimization problems. In combinatorial optimization, effectiveness of the chaotic search has already been clarified. First, an importance of chaos and autocorrelation with dumped oscillation for combinatorial optimization is shown. Next, in order to realize ideal solution search, the LSF is applied to the Hopfield-Tank neural network, the 2-opt method and the 2-exchange method. Effectiveness of the LSF is clarified even for the large problems for the traveling salesman problems and the quadratic assignment problems.

  • Automatic Retrieval of Action Video Shots from the Web Using Density-Based Cluster Analysis and Outlier Detection

    Nga Hang DO  Keiji YANAI  

     
    PAPER-Image Processing and Video Processing

      Pubricized:
    2016/07/21
      Vol:
    E99-D No:11
      Page(s):
    2788-2795

    In this paper, we introduce a fully automatic approach to construct action datasets from noisy Web video search results. The idea is based on combining cluster structure analysis and density-based outlier detection. For a specific action concept, first, we download its Web top search videos and segment them into video shots. We then organize these shots into subsets using density-based hierarchy clustering. For each set, we rank its shots by their outlier degrees which are determined as their isolatedness with respect to their surroundings. Finally, we collect high ranked shots as training data for the action concept. We demonstrate that with action models trained by our data, we can obtain promising precision rates in the task of action classification while offering the advantage of fully automatic, scalable learning. Experiment results on UCF11, a challenging action dataset, show the effectiveness of our method.

  • Distributed Decision Fusion over Nonideal Channels Using Scan Statistics

    Junhai LUO  Renqian ZOU  

     
    PAPER-Digital Signal Processing

      Vol:
    E99-A No:11
      Page(s):
    2019-2026

    Although many approaches about ideal channels have been proposed in previous researches, few authors considered the situation of nonideal communication links. In this paper, we study the problem of distributed decision fusion over nonideal channels by using the scan statistics. In order to obtain the fusion rule under nonideal channels, we set up the nonideal channels model with the modulation error, noise and signal attenuation. Under this model, we update the fusion rule by using the scan statstics. We firstly consider the fusion rule when sensors are distributed in grid, then derive the expressions of the detection probability and false alarm probability when sensors follow an uniform distribution. Extensive simulations are conducted in order to investigate the performance of our fusion rule and the influence of signal-noise ratio (SNR) on the detection and false alarm probability. These simulations show that the theoretical values of the global detection probability and the global false alarm probability are close to the experimental results, and the fusion rule also has high performance at the high SNR region. But there are some further researches need to do for solving the large computational complexity.

  • Improvements of Voice Timbre Control Based on Perceived Age in Singing Voice Conversion

    Kazuhiro KOBAYASHI  Tomoki TODA  Tomoyasu NAKANO  Masataka GOTO  Satoshi NAKAMURA  

     
    PAPER-Speech and Hearing

      Pubricized:
    2016/07/21
      Vol:
    E99-D No:11
      Page(s):
    2767-2777

    As one of the techniques enabling individual singers to produce the varieties of voice timbre beyond their own physical constraints, a statistical voice timbre control technique based on the perceived age has been developed. In this technique, the perceived age of a singing voice, which is the age of the singer as perceived by the listener, is used as one of the intuitively understandable measures to describe voice characteristics of the singing voice. The use of statistical voice conversion (SVC) with a singer-dependent multiple-regression Gaussian mixture model (MR-GMM), which effectively models the voice timbre variations caused by a change of the perceived age, makes it possible for individual singers to manipulate the perceived ages of their own singing voices while retaining their own singer identities. However, there still remain several issues; e.g., 1) a controllable range of the perceived age is limited; 2) quality of the converted singing voice is significantly degraded compared to that of a natural singing voice; and 3) each singer needs to sing the same phrase set as sung by a reference singer to develop the singer-dependent MR-GMM. To address these issues, we propose the following three methods; 1) a method using gender-dependent modeling to expand the controllable range of the perceived age; 2) a method using direct waveform modification based on spectrum differential to improve quality of the converted singing voice; and 3) a rapid unsupervised adaptation method based on maximum a posteriori (MAP) estimation to easily develop the singer-dependent MR-GMM. The experimental results show that the proposed methods achieve a wider controllable range of the perceived age, a significant quality improvement of the converted singing voice, and the development of the singer-dependnet MR-GMM using only a few arbitrary phrases as adaptation data.

  • Statistical Measurement of Electromagnetic Noise Characteristics of ESD in Wireless Frequency Bands and Influence Evaluation on Communication Performance

    Ryo NAKAYA  Hidenawo ANDO  Daisuke ANZAI  Jianqing WANG  Osamu FUJIWARA  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Pubricized:
    2016/05/25
      Vol:
    E99-B No:11
      Page(s):
    2399-2405

    Wireless body area networks (BANs) are attracting much attention due to their suitable for healthcare and medical applications. Unfortunately, electrostatic discharge (ESD) is a major electromagnetic (EM) noise source that can degrade wireless communication performance. In this study, we measure EM noise power in the 2.4GHz and 30MHz bands for indirect ESD testing specified in IEC 61000-4-2 standard, and derived a statistical ESD noise model from the measurement results. The ESD noise power was found to follow a lognormal distribution in both 2.4GHz and 30MHz bands. We use this ESD noise model to conduct bit error rate (BER) simulations in a communication channel with additive white Gaussian noise (AWGN) plus ESD noise at 2.4GHz and 30MHz bands. The result is that the BER performance is virtually the same in both bands, and decreases with the signal to noise power ratio (SNR). It is also shown that an error floor exists in the BER performances at both frequencies, which, if the ESD noise power is larger than the Gaussian noise, cannot be improved by increasing the SNR. Although the ESD noise power at 2.4GHz band is nearly 30dB smaller than that at 30MHz band, the signal attenuation along the human body at 2.4GHz band is much larger compared to 30MHz band. This may yield a similar SNR level at 30MHz and 2.4GHz bands in an ESD-dominated environment, so that the 2.4GHz band does not have an obvious merit for BAN applications. Since there are so many in-band interference sources at 2.4GHz band, the 30MHz band seems more promising for vital data transmission in a BAN scenario even in an ESD-dominated environment.

  • Light Diffusion Angle Dependence on Difference in Polymer Refractive Indices of Alternating Polymer Layer Structures

    Souichiro SEO  Masahiro NISHIZAWA  Yosei SHIBATA  Takahiro ISHINABE  Hideo FUJIKAKE  

     
    BRIEF PAPER

      Vol:
    E99-C No:11
      Page(s):
    1283-1286

    We investigated effects of ultraviolet illuminance and ratio of high- to low-refractive-index monomers on the layer structure and light diffusion properties of light-diffusing films with alternating polymer layer structures. We clarified that an increasing difference in refractive index between alternating polymer layers induced an increase in the diffusion angle.

  • An Adaptive Routing Protocol with Balanced Stochastic Route Exploration and Stabilization Based on Short-Term Memory

    Tomohiro NAKAO  Jun-nosuke TERAMAE  Naoki WAKAMIYA  

     
    PAPER

      Vol:
    E99-B No:11
      Page(s):
    2280-2288

    Due to rapid increases in the number of users and diversity of devices, temporal fluctuation of traffic on information communication network is becoming large and rapid recently. Especially, sudden traffic changes such as flash crowds often cause serious congestion on the network and result in nearly fatal slow down of date-communication speed. In order to keep communication quality high on the network, routing protocols that are scalable and able to quickly respond to rapid, and often unexpected, traffic fluctuation are highly desired. One of the promising approaches is the distributed routing protocol, which works without referring global information of the whole network but requires only limited informatin of it to realize route selection. These approaches include biologically inspired routing protocols based on the Adaptive Response by Attractor Selection model (ARAS), in which routing tables are updated along with only a scalar value reflecting communication quality measured on each router without evaluating communication quality over the whole network. However, the lack of global knowledge of the current status of the network often makes it difficult to respond promptly to traffic changes on the network that occurs at outside of the local scope of the protocol and causes inefficient use of network resources. In order to solve the essential problem of the local scope, we extend ARAS and propose a routing protocol with active and stochastic route exploration. The proposed protocol can obtain current communication quality of the network beyond its local scope and promptly responds to traffic changes occur on the network by utilizing the route exploration. In order to compensate destabilization of routing itself due to the active and stochastic exploration, we also introduce a short-term memory to the dynamics of the proposed attractor selection model. We conform by numerical simulations that the proposed protocol successfully balances rapid exploration with reliable routing owning to the memory term.

  • Efficient Multiplication Based on Dickson Bases over Any Finite Fields

    Sun-Mi PARK  Ku-Young CHANG  Dowon HONG  Changho SEO  

     
    PAPER-Algorithms and Data Structures

      Vol:
    E99-A No:11
      Page(s):
    2060-2074

    We propose subquadratic space complexity multipliers for any finite field $mathbb{F}_{q^n}$ over the base field $mathbb{F}_q$ using the Dickson basis, where q is a prime power. It is shown that a field multiplication in $mathbb{F}_{q^n}$ based on the Dickson basis results in computations of Toeplitz matrix vector products (TMVPs). Therefore, an efficient computation of a TMVP yields an efficient multiplier. In order to derive efficient $mathbb{F}_{q^n}$ multipliers, we develop computational schemes for a TMVP over $mathbb{F}_{q}$. As a result, the $mathbb{F}_{2^n}$ multipliers, as special cases of the proposed $mathbb{F}_{q^n}$ multipliers, have lower time complexities as well as space complexities compared with existing results. For example, in the case that n is a power of 3, the proposed $mathbb{F}_{2^n}$ multiplier for an irreducible Dickson trinomial has about 14% reduced space complexity and lower time complexity compared with the best known results.

  • Multi-User MIMO Channel Emulator with Automatic Channel Sounding Feedback

    Tran Thi Thao NGUYEN  Leonardo LANANTE  Yuhei NAGAO  Hiroshi OCHI  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E99-A No:11
      Page(s):
    1918-1927

    Wireless channel emulators are used for the performance evaluation of wireless systems when actual wireless environment test is infeasible. The main contribution of this paper is the design of a MU-MIMO channel emulator capable of sending channel feedback automatically to the access point from the generated channel coefficients after the programmable time duration. This function is used for MU beamforming features of IEEE 802.11ac. The second contribution is the low complexity design of MIMO channel emulator with a single path implementation for all MIMO channel taps. A single path design allows all elements of the MIMO channel matrix to use only one Gaussian noise generator, Doppler filter, spatial correlation channel and Rician fading emulator to minimize the hardware complexity. In addition, single path implementation allows the addition of the feedback channel output with only a few additional non-sequential elements which would otherwise double in a parallel implementation. To demonstrate the functionality of our MU-MIMO channel emulator, we present actual hardware emulator results of MU-BF receive signal constellation on oscilloscope.

  • Continuous Liquid Phase Synthesis of Europium and Bismuth Co-Doped Yttrium Vanadate Nanophosphor Using Microwave Heating Open Access

    Takashi KUNIMOTO  Yoshiko FUJITA  Hiroshi OKURA  

     
    INVITED PAPER

      Vol:
    E99-C No:11
      Page(s):
    1249-1254

    A continuous flow reactor equipped with a low-loss flow channel and a microwave cavity was developed for synthesizing nanophosphors. A continuous solution synthesis of YVO4:Eu,Bi nanophosphor was succeeded through the rapid hydrothermal method using this equipment. Internal quantum efficiency of YVO4:Eu,Bi nanophosphor obtained by 20 minutes microwave heating is about 30% at 320 nm as high as that obtained by 6 hours hydrothermal treatment in autoclave.

  • Evaluation of Adaptive Satellite Power Control Method Using Rain Radar Data

    Peeramed CHODKAVEEKITYADA  Hajime FUKUCHI  

     
    PAPER-Satellite Communications

      Pubricized:
    2016/06/01
      Vol:
    E99-B No:11
      Page(s):
    2450-2457

    Rain attenuation can drastically impact the service availability of satellite communication, especially in the higher frequency bands above 20 GHz, such as the Ka-band. Several countermeasures, including site and time diversity, have been proposed to maintain satellite link service. In this paper, we evaluate the performance of a power boost beam method, which is an adaptive satellite power control technology based on using rain radar data obtained throughout Japan to forecast the power margin. Boost beam analysis is considered for different beam sizes (50, 100, 150, and 200km) and beam numbers (1-4 beams) for a total of 16 cases. Moreover, we used a constant boost power corresponding to the rainfall rate of 20mm/h. The obtained results show that in comparison to the case with no boost, the effective rain intensity in each boost case was reduced.

  • Personalized Web Page Recommendation Based on Preference Footprint to Browsed Pages

    Kenta SERIZAWA  Sayaka KAMEI  Syuhei HAYASHI  Satoshi FUJITA  

     
    PAPER-Data Engineering, Web Information Systems

      Pubricized:
    2016/08/08
      Vol:
    E99-D No:11
      Page(s):
    2705-2715

    In this paper, a new scheme for personalized web page recommendation using multi-user search engine query information is proposed. Our contribution is a scheme that improves the accuracy of personalization for various types of contents (e.g., documents, images and music) without increasing user burden. The proposed scheme combines “preference footprints” for browsed pages with collaborative filtering. We acquire user interest using words that are relevant to queries submitted by users, attach all user interests to a page as a footprint when it is browsed, and evaluate the relevance of web pages in relation to words in footprints. The performance of the scheme is evaluated experimentally. The results indicate that the proposed scheme improves the precision and recall of previous schemes by 1%-24% and 80%-107%, respectively.

  • Proposal of Multiscale Retinex Using Illumination Adjustment for Digital Images

    Yi RU  Go TANAKA  

     
    LETTER-Image

      Vol:
    E99-A No:11
      Page(s):
    2003-2007

    In this letter, we propose a method for obtaining a clear and natural output image by tuning the illumination component in an input image. The proposed method is based on the retinex process and it is suitable for the image quality improvement of images of which illumination is insufficient.

  • Resource Allocation and Layer Selection for Scalable Video Streaming over Highway Vehicular Networks

    Ruijian AN  Zhi LIU  Hao ZHOU  Yusheng JI  

     
    PAPER-Intelligent Transport System

      Vol:
    E99-A No:11
      Page(s):
    1909-1917

    How to manage the video streaming in future networks is becoming a more and more challenging issue. Recent studies on vehicular networks depict a new picture of the next generation Intelligent Transport System (ITS), with high level road safety and more comfortable driving experience. To cope with the heterogeneous network development for the next generation cellular network, centralized medium control is promising to be employed upon Road Side Unit (RSU). To accommodate the QoS constraints posed by video services in vehicular networks, the scalable video coding (SVC) scheme in H.264/AVC standard family offers spatial and temporal scalabilities in the video dissemination. In this paper, we target the resource allocation and layer selection problem for the multi-user video streaming over highway scenario, by employing SVC coding scheme for the video contents. We propose a Resource Allocation and Layer Selection (RALS) algorithm, which explicitly takes account of the utility value of each Group Of Picture (GOP) among all the vehicular users. Simulation results show that our proposed RALS algorithm outperforms the comparison schemes in typical scenarios.

  • Micro-Vibration Patterns Generated from Shape Memory Alloy Actuators and the Detection of an Asymptomatic Tactile Sensation Decrease in Diabetic Patients

    Junichi DANJO  Sonoko DANJO  Yu NAKAMURA  Keiji UCHIDA  Hideyuki SAWADA  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2016/08/10
      Vol:
    E99-D No:11
      Page(s):
    2759-2766

    Diabetes mellitus is a group of metabolic diseases that cause high blood sugar due to functional problems with the pancreas or metabolism. Diabetic patients have few subjective symptoms and may experience decreased sensation without being aware of it. The commonly performed tests for sensory disorders are qualitative in nature. The authors pay attention to the decline of the sensitivity of tactile sensations, and develop a non-invasive method to detect the level of tactile sensation using a novel micro-vibration actuator that employs shape-memory alloy wires. Previously, we performed a pilot study that applied the device to 15 diabetic patients and confirmed a significant reduction in the tactile sensation in diabetic patients when compared to healthy subjects. In this study, we focus on the asymptomatic development of decreased sensation associated with diabetes mellitus. The objectives are to examine diabetic patients who are unaware of abnormal or decreased sensation using the quantitative tactile sensation measurement device and to determine whether tactile sensation is decreased in patients compared to healthy controls. The finger method is used to measure the Tactile Sensation Threshold (TST) score of the index and middle fingers using the new device and the following three procedures: TST-1, TST-4, and TST-8. TST scores ranged from 1 to 30 were compared between the two groups. The TST scores were significantly higher for the diabetic patients (P<0.05). The TST scores for the left fingers of diabetic patients and healthy controls were 5.9±6.2 and 2.7±2.9 for TST-1, 15.3±7.0 and 8.7±6.4 for TST-4, and 19.3±7.8 and 12.7±9.1 for TST-8. Our data suggest that the use of the new quantitative tactile sensation measurement device enables the detection of decreased tactile sensation in diabetic patients who are unaware of abnormal or decreased sensation compared to controls.

  • Quasi-Black Mask for Low-Cost LCDs by Patterned Alignment Films Formed by an Electro-Spray Deposition Method Open Access

    Yukihiro KUDOH  Yuta UCHIDA  Taiju TAKAHASHI  

     
    INVITED PAPER

      Vol:
    E99-C No:11
      Page(s):
    1244-1248

    A black mask (BM) is a layer used to improve the display quality by suppressing light leakage. In general, the BM is formed by a photolithography process. In this study, a novel technique for the fabrication of a quasi-black mask (q-BM) is proposed; the q-BM was composed of vertical and hybrid orientation areas, patterned by a separation coating technique using an electro-spray deposition method. Using our technique, the q-BM can be formed easily without the additional masks used for the BM.

  • A Visibility-Based Upper Bound for Android Unlock Patterns

    Jinwoo LEE  Jae Woo SEO  Kookrae CHO  Pil Joong LEE  Juneyeun KIM  Seung Hoon CHOI  Dae Hyun YUM  

     
    LETTER-Information Network

      Pubricized:
    2016/07/25
      Vol:
    E99-D No:11
      Page(s):
    2814-2816

    The Android pattern unlock is a popular graphical password scheme, where a user is presented a 3×3 grid and required to draw a pattern on the onscreen grid. Each pattern is a sequence of at least four contact points with some restrictions. Theoretically, the security level of unlock patterns is determined by the size of the pattern space. However, the number of possible patterns is only known for 3×3 and 4×4 grids, which was computed by brute-force enumeration. The only mathematical formula for the number of possible patterns is a permutation-based upper bound. In this article, we present an improved upper bound by counting the number of “visible” points that can be directly reached by a point.

  • Distributed Optimization in Transportation and Logistics Networks Open Access

    K. Y. Michael WONG  David SAAD  Chi Ho YEUNG  

     
    INVITED PAPER

      Vol:
    E99-B No:11
      Page(s):
    2237-2246

    Many important problems in communication networks, transportation networks, and logistics networks are solved by the minimization of cost functions. In general, these can be complex optimization problems involving many variables. However, physicists noted that in a network, a node variable (such as the amount of resources of the nodes) is connected to a set of link variables (such as the flow connecting the node), and similarly each link variable is connected to a number of (usually two) node variables. This enables one to break the problem into local components, often arriving at distributive algorithms to solve the problems. Compared with centralized algorithms, distributed algorithms have the advantages of lower computational complexity, and lower communication overhead. Since they have a faster response to local changes of the environment, they are especially useful for networks with evolving conditions. This review will cover message-passing algorithms in applications such as resource allocation, transportation networks, facility location, traffic routing, and stability of power grids.

  • Adaptive Local Thresholding for Co-Localization Detection in Multi-Channel Fluorescence Microscopic Images

    Eisuke ITO  Yusuke TOMARU  Akira IIZUKA  Hirokazu HIRAI  Tsuyoshi KATO  

     
    LETTER-Biological Engineering

      Pubricized:
    2016/07/27
      Vol:
    E99-D No:11
      Page(s):
    2851-2855

    Automatic detection of immunoreactive areas in fluorescence microscopic images is becoming a key technique in the field of biology including neuroscience, although it is still challenging because of several reasons such as low signal-to-noise ratio and contrast variation within an image. In this study, we developed a new algorithm that exhaustively detects co-localized areas in multi-channel fluorescence images, where shapes of target objects may differ among channels. Different adaptive binarization thresholds for different local regions in different channels are introduced and the condition of each segment is assessed to recognize the target objects. The proposed method was applied to detect immunoreactive spots that labeled membrane receptors on dendritic spines of mouse cerebellar Purkinje cells. Our method achieved the best detection performance over five pre-existing methods.

3461-3480hit(18690hit)