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[Keyword] PAR(2741hit)

201-220hit(2741hit)

  • Adaptively Simulation-Secure Attribute-Hiding Predicate Encryption

    Pratish DATTA  Tatsuaki OKAMOTO  Katsuyuki TAKASHIMA  

     
    PAPER-Cryptographic Techniques

      Pubricized:
    2020/04/13
      Vol:
    E103-D No:7
      Page(s):
    1556-1597

    This paper demonstrates how to achieve simulation-based strong attribute hiding against adaptive adversaries for predicate encryption (PE) schemes supporting expressive predicate families under standard computational assumptions in bilinear groups. Our main result is a simulation-based adaptively strongly partially-hiding PE (PHPE) scheme for predicates computing arithmetic branching programs (ABP) on public attributes, followed by an inner-product predicate on private attributes. This simultaneously generalizes attribute-based encryption (ABE) for boolean formulas and ABP's as well as strongly attribute-hiding PE schemes for inner products. The proposed scheme is proven secure for any a priori bounded number of ciphertexts and an unbounded (polynomial) number of decryption keys, which is the best possible in the simulation-based adaptive security framework. This directly implies that our construction also achieves indistinguishability-based strongly partially-hiding security against adversaries requesting an unbounded (polynomial) number of ciphertexts and decryption keys. The security of the proposed scheme is derived under (asymmetric version of) the well-studied decisional linear (DLIN) assumption. Our work resolves an open problem posed by Wee in TCC 2017, where his result was limited to the semi-adaptive setting. Moreover, our result advances the current state of the art in both the fields of simulation-based and indistinguishability-based strongly attribute-hiding PE schemes. Our main technical contribution lies in extending the strong attribute hiding methodology of Okamoto and Takashima [EUROCRYPT 2012, ASIACRYPT 2012] to the framework of simulation-based security and beyond inner products.

  • An Efficient Method for Graph Repartitioning in Distributed Environments

    He LI  YanNa LIU  XuHua WANG  LiangCai SU  Hang YUAN  JaeSoo YOO  

     
    LETTER-Data Engineering, Web Information Systems

      Pubricized:
    2020/04/20
      Vol:
    E103-D No:7
      Page(s):
    1773-1776

    Due to most of the existing graph repartitioning methods are known for poor efficiency in distributed environments. In this paper, we introduce a new graph repartitioning method with two phases in distributed environments. In the first phase, a local method is designed to identify all the potential candidate vertices that should be moved to the other partitions at once in each partition locally. In the second phase, a streaming graph processing model is adopted to reassign the candidate vertices to achieve lightweight graph repartitioning. During the reassignment of the vertex, we propose an objective function to balance both the load balance and the number of crossing edges among the distributed partitions. The experimental results with a large set of real word and synthetic graph datasets show that the communication cost can be reduced by nearly 1 to 2 orders of magnitude compared with the existing methods.

  • Survivable Virtual Network Topology Protection Method Based on Particle Swarm Optimization

    Guangyuan LIU  Daokun CHEN  

     
    LETTER-Information Network

      Pubricized:
    2020/03/04
      Vol:
    E103-D No:6
      Page(s):
    1414-1418

    Survivable virtual network embedding (SVNE) is one of major challenges of network virtualization. In order to improve the utilization rate of the substrate network (SN) resources with virtual network (VN) topology connectivity guarantee under link failure in SN, we first establishes an Integer Linear Programming (ILP) model for that under SN supports path splitting. Then we designs a novel survivable VN topology protection method based on particle swarm optimization (VNE-PSO), which redefines the parameters and related operations of particles with the embedding overhead as the fitness function. Simulation results show that the solution significantly improves the long-term average revenue of the SN, the acceptance rate of VN requests, and reduces the embedding time compared with the existing research results.

  • Partial Label Metric Learning Based on Statistical Inference

    Tian XIE  Hongchang CHEN  Tuosiyu MING  Jianpeng ZHANG  Chao GAO  Shaomei LI  Yuehang DING  

     
    PAPER-Artificial Intelligence, Data Mining

      Pubricized:
    2020/03/05
      Vol:
    E103-D No:6
      Page(s):
    1355-1361

    In partial label data, the ground-truth label of a training example is concealed in a set of candidate labels associated with the instance. As the ground-truth label is inaccessible, it is difficult to train the classifier via the label information. Consequently, manifold structure information is adopted, which is under the assumption that neighbor/similar instances in the feature space have similar labels in the label space. However, the real-world data may not fully satisfy this assumption. In this paper, a partial label metric learning method based on likelihood-ratio test is proposed to make partial label data satisfy the manifold assumption. Moreover, the proposed method needs no objective function and treats the data pairs asymmetrically. The experimental results on several real-world PLL datasets indicate that the proposed method outperforms the existing partial label metric learning methods in terms of classification accuracy and disambiguation accuracy while costs less time.

  • A Fast Multi-Type Tree Decision Algorithm for VVC Based on Pixel Difference of Sub-Blocks

    Zhi LIU  Mengjun DONG  Mengmeng ZHANG  

     
    LETTER-Coding Theory

      Pubricized:
    2020/03/02
      Vol:
    E103-A No:6
      Page(s):
    856-859

    In the upcoming video coding standard VVC (Versatile Video Coding, H.266), a new coding block structure named quadtree nested multi-type trees (MTT) has been proposed. Compared with the quadtree structure defined in HEVC (High Efficiency Video Coding), the partition structure of MTT can achieve better coding performance. Since the splitting scheme of a CU (Coding Unit) need to be calculated recursively, the computational complexity is significantly increased. To reduce computational complexity as well as maintain compression performance, a fast multi-type tree decision algorithm is proposed. The application of binary and ternary tree in horizontal or vertical direction is found to be closely related to the characteristics of CU in this paper, and a metric named pixel difference of sub-blocks (SBPD) is defined to measure the characteristics of CU in different splitting type. By comparing the SBPD in horizontal and vertical sub-blocks, the selection of binary and ternary tree can be decided in advance, so as to skip some redundant splitting modes. Experimental results show that compared with the original reference software VTM 4.0, the average time saving of the proposed algorithm is 27% and the BD-rate is only increased by 0.55%.

  • Broadband RF Power Amplifier with Combination of Large Signal X-Parameter and Real Frequency Techniques

    Ragavan KRISHNAMOORTHY  Narendra KUMAR  Andrei GREBENNIKOV  Binboga Siddik YARMAN  Harikrishnan RAMIAH  

     
    PAPER-Microwaves, Millimeter-Waves

      Pubricized:
    2019/11/27
      Vol:
    E103-C No:5
      Page(s):
    225-230

    A new design approach of broadband RF power amplifier (PA) is introduced in this work with combination of large signal X-parameter and Real-Frequency Technique (RFT). A theoretical analysis of large signal X-parameter is revisited, and a simplification method is introduced to determine the optimum large signal impedances of a Gallium Nitride HEMT (GaN HEMT) device. With the optimum impedance extraction over the wide frequency range (0.3 to 2.0 GHz), a wideband matching network is constructed employing RFT and the final design is implemented with practical mixed-lumped elements. The prototype broadband RF PA demonstrates an output power of 40 dBm. The average drain efficiency of the PA is found to be more than 60%; while exhibiting acceptable flat gain performance (12±0.25 dB) over the frequency band of (0.3-2.0 GHz). The PA designed using the proposed approach yields in small form factor and relatively lower production cost over those of similar PAs designed with the classical methods. It is expected that the newly proposed design method will be utilized to construct power amplifiers for radio communications applications.

  • Air Quality Index Forecasting via Deep Dictionary Learning

    Bin CHEN  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2020/02/20
      Vol:
    E103-D No:5
      Page(s):
    1118-1125

    Air quality index (AQI) is a non-dimensional index for the description of air quality, and is widely used in air quality management schemes. A novel method for Air Quality Index Forecasting based on Deep Dictionary Learning (AQIF-DDL) and machine vision is proposed in this paper. A sky image is used as the input of the method, and the output is the forecasted AQI value. The deep dictionary learning is employed to automatically extract the sky image features and achieve the AQI forecasting. The idea of learning deeper dictionary levels stemmed from the deep learning is also included to increase the forecasting accuracy and stability. The proposed AQIF-DDL is compared with other deep learning based methods, such as deep belief network, stacked autoencoder and convolutional neural network. The experimental results indicate that the proposed method leads to good performance on AQI forecasting.

  • Cost-Sensitive and Sparse Ladder Network for Software Defect Prediction

    Jing SUN  Yi-mu JI  Shangdong LIU  Fei WU  

     
    LETTER-Software Engineering

      Pubricized:
    2020/01/29
      Vol:
    E103-D No:5
      Page(s):
    1177-1180

    Software defect prediction (SDP) plays a vital role in allocating testing resources reasonably and ensuring software quality. When there are not enough labeled historical modules, considerable semi-supervised SDP methods have been proposed, and these methods utilize limited labeled modules and abundant unlabeled modules simultaneously. Nevertheless, most of them make use of traditional features rather than the powerful deep feature representations. Besides, the cost of the misclassification of the defective modules is higher than that of defect-free ones, and the number of the defective modules for training is small. Taking the above issues into account, we propose a cost-sensitive and sparse ladder network (CSLN) for SDP. We firstly introduce the semi-supervised ladder network to extract the deep feature representations. Besides, we introduce the cost-sensitive learning to set different misclassification costs for defective-prone and defect-free-prone instances to alleviate the class imbalance problem. A sparse constraint is added on the hidden nodes in ladder network when the number of hidden nodes is large, which enables the model to find robust structures of the data. Extensive experiments on the AEEEM dataset show that the CSLN outperforms several state-of-the-art semi-supervised SDP methods.

  • Korean-Vietnamese Neural Machine Translation with Named Entity Recognition and Part-of-Speech Tags

    Van-Hai VU  Quang-Phuoc NGUYEN  Kiem-Hieu NGUYEN  Joon-Choul SHIN  Cheol-Young OCK  

     
    PAPER-Natural Language Processing

      Pubricized:
    2020/01/15
      Vol:
    E103-D No:4
      Page(s):
    866-873

    Since deep learning was introduced, a series of achievements has been published in the field of automatic machine translation (MT). However, Korean-Vietnamese MT systems face many challenges because of a lack of data, multiple meanings of individual words, and grammatical diversity that depends on context. Therefore, the quality of Korean-Vietnamese MT systems is still sub-optimal. This paper discusses a method for applying Named Entity Recognition (NER) and Part-of-Speech (POS) tagging to Vietnamese sentences to improve the performance of Korean-Vietnamese MT systems. In terms of implementation, we used a tool to tag NER and POS in Vietnamese sentences. In addition, we had access to a Korean-Vietnamese parallel corpus with more than 450K paired sentences from our previous research paper. The experimental results indicate that tagging NER and POS in Vietnamese sentences can improve the quality of Korean-Vietnamese Neural MT (NMT) in terms of the Bi-Lingual Evaluation Understudy (BLEU) and Translation Error Rate (TER) score. On average, our MT system improved by 1.21 BLEU points or 2.33 TER scores after applying both NER and POS tagging to the Vietnamese corpus. Due to the structural features of language, the MT systems in the Korean to Vietnamese direction always give better BLEU and TER results than translation machines in the reverse direction.

  • Compiler Software Coherent Control for Embedded High Performance Multicore

    Boma A. ADHI  Tomoya KASHIMATA  Ken TAKAHASHI  Keiji KIMURA  Hironori KASAHARA  

     
    PAPER

      Vol:
    E103-C No:3
      Page(s):
    85-97

    The advancement of multicore technology has made hundreds or even thousands of cores processor on a single chip possible. However, on a larger scale multicore, a hardware-based cache coherency mechanism becomes overwhelmingly complicated, hot, and expensive. Therefore, we propose a software coherence scheme managed by a parallelizing compiler for shared-memory multicore systems without a hardware cache coherence mechanism. Our proposed method is simple and efficient. It is built into OSCAR automatic parallelizing compiler. The OSCAR compiler parallelizes the coarse grain task, analyzes stale data and line sharing in the program, then solves those problems by simple program restructuring and data synchronization. Using our proposed method, we compiled 10 benchmark programs from SPEC2000, SPEC2006, NAS Parallel Benchmark (NPB), and MediaBench II. The compiled binaries then are run on Renesas RP2, an 8 cores SH-4A processor, and a custom 8-core Altera Nios II system on Altera Arria 10 FPGA. The cache coherence hardware on the RP2 processor is only available for up to 4 cores. The RP2's cache coherence hardware can also be turned off for non-coherence cache mode. The Nios II multicore system does not have any hardware cache coherence mechanism; therefore, running a parallel program is difficult without any compiler support. The proposed method performed as good as or better than the hardware cache coherence scheme while still provided the correct result as the hardware coherence mechanism. This method allows a massive array of shared memory CPU cores in an HPC setting or a simple non-coherent multicore embedded CPU to be easily programmed. For example, on the RP2 processor, the proposed software-controlled non-coherent-cache (NCC) method gave us 2.6 times speedup for SPEC 2000 “equake” with 4 cores against sequential execution while got only 2.5 times speedup for 4 cores MESI hardware coherent control. Also, the software coherence control gave us 4.4 times speedup for 8 cores with no hardware coherence mechanism available.

  • Parameter Estimation for Multiple Chirp Signals Based on Single Channel Nyquist Folding Receiver

    Zhaoyang QIU  Qi ZHANG  Minhong SUN  Jun ZHU  

     
    LETTER-Digital Signal Processing

      Vol:
    E103-A No:3
      Page(s):
    623-628

    The modern radar signals are in a wide frequency space. The receiving bandwidth of the radar reconnaissance receiver should be wide enough to intercept the modern radar signals. The Nyquist folding receiver (NYFR) is a novel wideband receiving architecture and it has a high intercept probability. Chirp signals are widely used in modern radar system. Because of the wideband receiving ability, the NYFR will receive the concurrent multiple chirp signals. In this letter, we propose a novel parameter estimation algorithm for the multiple chirp signals intercepted by single channel NYFR. Compared with the composite NYFR, the proposed method can save receiving resources. In addition, the proposed approach can estimate the parameters of the chirp signals even the NYFR outputs are under frequency aliasing circumstance. Simulation results show the efficacy of the proposed method.

  • Parallelization of Boost and Buck Type DC-DC Converters by Individual Passivity-Based Control Open Access

    Yuma MURAKAWA  Yuhei SADANDA  Takashi HIKIHARA  

     
    PAPER-Systems and Control

      Vol:
    E103-A No:3
      Page(s):
    589-595

    This paper discusses the parallelization of boost and buck converters. Passivity-based control is applied to each converter to achieve the asymptotic stability of the system. The ripple characteristics, error characteristics, and time constants of the parallelized converters are discussed with considering the dependency on the feedback gains. The numerical results are confirmed to coincide with the results in the experiment for certain feedback gains. The stability of the system is also discussed in simulation and experiment. The results will be a step to achieve the design of parallel converters.

  • A 2D-DOA Estimation Algorithm for Double L-Shaped Array in Unknown Sound Velocity Environment

    Gengxin NING  Shenjie JIANG  Xuejin ZHAO  Cui YANG  

     
    PAPER-Antennas and Propagation

      Pubricized:
    2019/09/06
      Vol:
    E103-B No:3
      Page(s):
    240-246

    This paper presents a two-dimensional (2D) DOA algorithm for double L-shaped arrays. The algorithm is applied to the underwater environment for eliminating the performance error caused by the sound speed uncertainty factor. By introducing the third dimensional array, the algorithm eliminates the sound velocity variable in the depression angle expression, so that the DOA estimation no longer considering the true value of unknown sound velocity. In order to determine the parameters of a three-dimensional array, a parameter matching method with the double L-shaped array is also proposed. Simulations show that the proposed algorithm outperforms the conventional 2D-DOA estimation algorithm in unknown sound velocity environment.

  • Analysis of Antenna Performance Degradation due to Coupled Electromagnetic Interference from Nearby Circuits

    Hosang LEE  Jawad YOUSAF  Kwangho KIM  Seongjin MUN  Chanseok HWANG  Wansoo NAH  

     
    PAPER-Electromagnetic Theory

      Pubricized:
    2019/08/27
      Vol:
    E103-C No:3
      Page(s):
    110-118

    This paper analyzes and compares two methods to estimate electromagnetically coupled noises introduced to an antenna due to the nearby circuits at a circuit design stage. One of them is to estimate the power spectrum, and the other one is to estimate the active S11 parameter at the victim antenna, respectively, and both of them use simulated standard S-parameters for the electromagnetic coupling in the circuit. They also need the assumed or measured excitation of noise sources. To confirm the validness of the two methods, an evaluation board consisting of an antenna and noise sources were designed and fabricated in which voltage controlled oscillator (VCO) chips are placed as noise sources. The generated electromagnetic noises are transferred to an antenna via loop-shaped transmission lines, degrading the performance of the antenna. In this paper, detailed analysis procedures are described using the evaluation board, and it is shown that the two methods are equivalent to each other in terms of the induced voltages in the antenna. Finally, a procedure to estimate antenna performance degradation at the design stage is summarized.

  • Real-Time Generic Object Tracking via Recurrent Regression Network

    Rui CHEN  Ying TONG  Ruiyu LIANG  

     
    PAPER-Artificial Intelligence, Data Mining

      Pubricized:
    2019/12/20
      Vol:
    E103-D No:3
      Page(s):
    602-611

    Deep neural networks have achieved great success in visual tracking by learning a generic representation and leveraging large amounts of training data to improve performance. Most generic object trackers are trained from scratch online and do not benefit from a large number of videos available for offline training. We present a real-time generic object tracker capable of incorporating temporal information into its model, learning from many examples offline and quickly updating online. During the training process, the pre-trained weight of convolution layer is updated lagging behind, and the input video sequence length is gradually increased for fast convergence. Furthermore, only the hidden states in recurrent network are updated to guarantee the real-time tracking speed. The experimental results show that the proposed tracking method is capable of tracking objects at 150 fps with higher predicting overlap rate, and achieves more robustness in multiple benchmarks than state-of-the-art performance.

  • Simultaneous Estimation of Object Region and Depth in Participating Media Using a ToF Camera

    Yuki FUJIMURA  Motoharu SONOGASHIRA  Masaaki IIYAMA  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2019/12/03
      Vol:
    E103-D No:3
      Page(s):
    660-673

    Three-dimensional (3D) reconstruction and scene depth estimation from 2-dimensional (2D) images are major tasks in computer vision. However, using conventional 3D reconstruction techniques gets challenging in participating media such as murky water, fog, or smoke. We have developed a method that uses a continuous-wave time-of-flight (ToF) camera to estimate an object region and depth in participating media simultaneously. The scattered light observed by the camera is saturated, so it does not depend on the scene depth. In addition, received signals bouncing off distant points are negligible due to light attenuation, and thus the observation of such a point contains only a scattering component. These phenomena enable us to estimate the scattering component in an object region from a background that only contains the scattering component. The problem is formulated as robust estimation where the object region is regarded as outliers, and it enables the simultaneous estimation of an object region and depth on the basis of an iteratively reweighted least squares (IRLS) optimization scheme. We demonstrate the effectiveness of the proposed method using captured images from a ToF camera in real foggy scenes and evaluate the applicability with synthesized data.

  • Leveraging Neural Caption Translation with Visually Grounded Paraphrase Augmentation

    Johanes EFFENDI  Sakriani SAKTI  Katsuhito SUDOH  Satoshi NAKAMURA  

     
    PAPER-Natural Language Processing

      Pubricized:
    2019/11/25
      Vol:
    E103-D No:3
      Page(s):
    674-683

    Since a concept can be represented by different vocabularies, styles, and levels of detail, a translation task resembles a many-to-many mapping task from a distribution of sentences in the source language into a distribution of sentences in the target language. This viewpoint, however, is not fully implemented in current neural machine translation (NMT), which is one-to-one sentence mapping. In this study, we represent the distribution itself as multiple paraphrase sentences, which will enrich the model context understanding and trigger it to produce numerous hypotheses. We use a visually grounded paraphrase (VGP), which uses images as a constraint of the concept in paraphrasing, to guarantee that the created paraphrases are within the intended distribution. In this way, our method can also be considered as incorporating image information into NMT without using the image itself. We implement this idea by crowdsourcing a paraphrasing corpus that realizes VGP and construct neural paraphrasing that behaves as expert models in a NMT. Our experimental results reveal that our proposed VGP augmentation strategies showed improvement against a vanilla NMT baseline.

  • Local Memory Mapping of Multicore Processors on an Automatic Parallelizing Compiler

    Yoshitake OKI  Yuto ABE  Kazuki YAMAMOTO  Kohei YAMAMOTO  Tomoya SHIRAKAWA  Akimasa YOSHIDA  Keiji KIMURA  Hironori KASAHARA  

     
    PAPER

      Vol:
    E103-C No:3
      Page(s):
    98-109

    Utilization of local memory from real-time embedded systems to high performance systems with multi-core processors has become an important factor for satisfying hard deadline constraints. However, challenges lie in the area of efficiently managing the memory hierarchy, such as decomposing large data into small blocks to fit onto local memory and transferring blocks for reuse and replacement. To address this issue, this paper presents a compiler optimization method that automatically manage local memory of multi-core processors. The method selects and maps multi-dimensional data onto software specified memory blocks called Adjustable Blocks. These blocks are hierarchically divisible with varying sizes defined by the features of the input application. Moreover, the method introduces mapping structures called Template Arrays to maintain the indices of the decomposed multi-dimensional data. The proposed work is implemented on the OSCAR automatic parallelizing compiler and evaluations were performed on the Renesas RP2 8-core processor. Experimental results from NAS Parallel Benchmark, SPEC benchmark, and multimedia applications show the effectiveness of the method, obtaining maximum speed-ups of 20.44 with 8 cores utilizing local memory from single core sequential versions that use off-chip memory.

  • Rust Detection of Steel Structure via One-Class Classification and L2 Sparse Representation with Decision Fusion

    Guizhong ZHANG  Baoxian WANG  Zhaobo YAN  Yiqiang LI  Huaizhi YANG  

     
    LETTER-Artificial Intelligence, Data Mining

      Pubricized:
    2019/11/11
      Vol:
    E103-D No:2
      Page(s):
    450-453

    In this work, we present one novel rust detection method based upon one-class classification and L2 sparse representation (SR) with decision fusion. Firstly, a new color contrast descriptor is proposed for extracting the rust features of steel structure images. Considering that the patterns of rust features are more simplified than those of non-rust ones, one-class support vector machine (SVM) classifier and L2 SR classifier are designed with these rust image features, respectively. After that, a multiplicative fusion rule is advocated for combining the one-class SVM and L2 SR modules, thereby achieving more accurate rust detecting results. In the experiments, we conduct numerous experiments, and when compared with other developed rust detectors, the presented method can offer better rust detecting performances.

  • Shift Invariance Property of a Non-Negative Matrix Factorization

    Hideyuki IMAI  

     
    LETTER-General Fundamentals and Boundaries

      Vol:
    E103-A No:2
      Page(s):
    580-581

    We consider a property about a result of non-negative matrix factorization under a parallel moving of data points. The shape of a cloud of original data points and that of data points moving parallel to a vector are identical. Thus it is sometimes required that the coefficients to basis vectors of both data points are also identical from the viewpoint of classification. We show a necessary and sufficient condition for such an invariance property under a translation of the data points.

201-220hit(2741hit)