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3161-3180hit(16314hit)

  • Efficient Subversion of Symmetric Encryption with Random Initialization Vector

    Joonsang BAEK  Ilsun YOU  

     
    LETTER-Information Network

      Pubricized:
    2016/01/14
      Vol:
    E99-D No:4
      Page(s):
    1251-1254

    This paper presents an efficient subverted symmetric encryption scheme, which outputs a random initialization vector (IV). Compared with the available scheme of the same kind in the literature, our attack provides a saboteur (big brother) with much faster recovery of a key used in a victim's symmetric encryption scheme. Our result implies that care must be taken when a symmetric encryption scheme with a random IV such as randomized CBC is deployed.

  • Feature-Based On-Line Object Tracking Combining Both Keypoints and Quasi-Keypoints Matching

    Quan MIAO  Chun ZHANG  Long MENG  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2016/01/21
      Vol:
    E99-D No:4
      Page(s):
    1264-1267

    This paper proposes a novel object tracking method via online boosting. The on-line boosting technique is combined with local features to treat tracking as a keypoint matching problem. First, We improve matching reliability by exploiting the statistical repeatability of local features. In addition, we propose 2D scale-rotation invariant quasi-keypoint matching to further improve matching efficiency. Benefiting from SURF feature's statistical repeatability and the complementary quasi-keypoint matching technique, we can easily find reliable matching pairs and thus perform accurate and stable tracking. Experimental results show that the proposed method achieves better performance compared with previously reported trackers.

  • Experimental Study on Battery-Less Sensor Network Activated by Multi-Point Wireless Energy Transmission

    Daiki MAEHARA  Gia Khanh TRAN  Kei SAKAGUCHI  Kiyomichi ARAKI  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:4
      Page(s):
    905-916

    This paper empirically validates battery-less sensor activation via wireless energy transmission to release sensors from wires and batteries. To seamlessly extend the coverage and activate sensor nodes distributed in any indoor environment, we proposed multi-point wireless energy transmission with carrier shift diversity. In this scheme, multiple transmitters are employed to compensate path-loss attenuation and orthogonal frequencies are allocated to the multiple transmitters to avoid the destructive interference that occurs when the same frequency is used by all transmitters. In our previous works, the effectiveness of the proposed scheme was validated theoretically and also empirically by using just a spectrum analyzer to measure the received power. In this paper, we develop low-energy battery-less sensor nodes whose consumed power and required received power for activation are respectively 142µW and 400µW. In addition, we conduct indoor experiments in which the received power and activation of battery-less sensor node are simultaneously observed by using the developed battery-less sensor node and a spectrum analyzer. The results show that the coverage of single-point and multi-point wireless energy transmission without carrier shift diversity are, respectively, 84.4% and 83.7%, while the coverage of the proposed scheme is 100%. It can be concluded that the effectiveness of the proposed scheme can be verified by our experiments using real battery-less sensor nodes.

  • Cyber Physical Security for Industrial Control Systems and IoT Open Access

    Kazukuni KOBARA  

     
    INVITED PAPER

      Pubricized:
    2016/01/13
      Vol:
    E99-D No:4
      Page(s):
    787-795

    Cyber-attacks and cybersecurity used to be the issues for those who use Internet and computers. The issues, however, are expanding to anyone who does not even use them directly. The society is gradually and heavily depending on networks and computers. They are not closed within a cyberspace anymore and having interaction with our real world with sensors and actuators. Such systems are known as CPS (Cyber Physical Systems), IoT/E (Internet of Things/Everything), Industry 4.0, Industrial Internet, M2M, etc. No matter what they are called, exploitation of any of these systems may cause a serious influence to our real life and appropriate countermeasures must be taken to mitigate the risks. In this paper, cybersecurity in ICS (Industrial Control Systems) is reviewed as a leading example of cyber physical security for critical infrastructures. Then as a future aspect of it, IoT security for consumers is explained.

  • Incorporation of Target Specific Knowledge for Sentiment Analysis on Microblogging

    Yongyos KAEWPITAKKUN  Kiyoaki SHIRAI  

     
    PAPER

      Pubricized:
    2016/01/14
      Vol:
    E99-D No:4
      Page(s):
    959-968

    Sentiment analysis of microblogging has become an important classification task because a large amount of user-generated content is published on the Internet. In Twitter, it is common that a user expresses several sentiments in one tweet. Therefore, it is important to classify the polarity not of the whole tweet but of a specific target about which people express their opinions. Moreover, the performance of the machine learning approach greatly depends on the domain of the training data and it is very time-consuming to manually annotate a large set of tweets for a specific domain. In this paper, we propose a method for sentiment classification at the target level by incorporating the on-target sentiment features and user-aware features into the classifier trained automatically from the data createdfor the specific target. An add-on lexicon, extended target list, and competitor list are also constructed as knowledge sources for the sentiment analysis. None of the processes in the proposed framework require manual annotation. The results of our experiment show that our method is effective and improves on the performance of sentiment classification compared to the baselines.

  • Feature-Chain Based Malware Detection Using Multiple Sequence Alignment of API Call

    Hyun-Joo KIM  Jong-Hyun KIM  Jung-Tai KIM  Ik-Kyun KIM  Tai-Myung CHUNG  

     
    PAPER

      Pubricized:
    2016/01/28
      Vol:
    E99-D No:4
      Page(s):
    1071-1080

    The recent cyber-attacks utilize various malware as a means of attacks for the attacker's malicious purposes. They are aimed to steal confidential information or seize control over major facilities after infiltrating the network of a target organization. Attackers generally create new malware or many different types of malware by using an automatic malware creation tool which enables remote control over a target system easily and disturbs trace-back of these attacks. The paper proposes a generation method of malware behavior patterns as well as the detection techniques in order to detect the known and even unknown malware efficiently. The behavior patterns of malware are generated with Multiple Sequence Alignment (MSA) of API call sequences of malware. Consequently, we defined these behavior patterns as a “feature-chain” of malware for the analytical purpose. The initial generation of the feature-chain consists of extracting API call sequences with API hooking library, classifying malware samples by the similar behavior, and making the representative sequences from the MSA results. The detection mechanism of numerous malware is performed by measuring similarity between API call sequence of a target process (suspicious executables) and feature-chain of malware. By comparing with other existing methods, we proved the effectiveness of our proposed method based on Longest Common Subsequence (LCS) algorithm. Also we evaluated that our method outperforms other antivirus systems with 2.55 times in detection rate and 1.33 times in accuracy rate for malware detection.

  • Combining Human Action Sensing of Wheelchair Users and Machine Learning for Autonomous Accessibility Data Collection

    Yusuke IWASAWA  Ikuko EGUCHI YAIRI  Yutaka MATSUO  

     
    PAPER-Rehabilitation Engineering and Assistive Technology

      Pubricized:
    2016/01/22
      Vol:
    E99-D No:4
      Page(s):
    1153-1161

    The recent increase in the use of intelligent devices such as smartphones has enhanced the relationship between daily human behavior sensing and useful applications in ubiquitous computing. This paper proposes a novel method inspired by personal sensing technologies for collecting and visualizing road accessibility at lower cost than traditional data collection methods. To evaluate the methodology, we recorded outdoor activities of nine wheelchair users for approximately one hour each by using an accelerometer on an iPod touch and a camcorder, gathered the supervised data from the video by hand, and estimated the wheelchair actions as a measure of street level accessibility in Tokyo. The system detected curb climbing, moving on tactile indicators, moving on slopes, and stopping, with F-scores of 0.63, 0.65, 0.50, and 0.91, respectively. In addition, we conducted experiments with an artificially limited number of training data to investigate the number of samples required to estimate the target.

  • Distributed Compressed Video Sensing with Joint Optimization of Dictionary Learning and l1-Analysis Based Reconstruction

    Fang TIAN  Jie GUO  Bin SONG  Haixiao LIU  Hao QIN  

     
    PAPER-Image Processing and Video Processing

      Pubricized:
    2016/01/21
      Vol:
    E99-D No:4
      Page(s):
    1202-1211

    Distributed compressed video sensing (DCVS), combining advantages of compressed sensing and distributed video coding, is developed as a novel and powerful system to get an encoder with low complexity. Nevertheless, it is still unclear how to explore the method to achieve an effective video recovery through utilizing realistic signal characteristics as much as possible. Based on this, we present a novel spatiotemporal dictionary learning (DL) based reconstruction method for DCVS, where both the DL model and the l1-analysis based recovery with correlation constraints are included in the minimization problem to achieve the joint optimization of sparse representation and signal reconstruction. Besides, an alternating direction method with multipliers (ADMM) based numerical algorithm is outlined for solving the underlying optimization problem. Simulation results demonstrate that the proposed method outperforms other methods, with 0.03-4.14 dB increases in PSNR and a 0.13-15.31 dB gain for non-key frames.

  • Topic Representation of Researchers' Interests in a Large-Scale Academic Database and Its Application to Author Disambiguation

    Marie KATSURAI  Ikki OHMUKAI  Hideaki TAKEDA  

     
    PAPER

      Pubricized:
    2016/01/14
      Vol:
    E99-D No:4
      Page(s):
    1010-1018

    It is crucial to promote interdisciplinary research and recommend collaborators from different research fields via academic database analysis. This paper addresses a problem to characterize researchers' interests with a set of diverse research topics found in a large-scale academic database. Specifically, we first use latent Dirichlet allocation to extract topics as distributions over words from a training dataset. Then, we convert the textual features of a researcher's publications to topic vectors, and calculate the centroid of these vectors to summarize the researcher's interest as a single vector. In experiments conducted on CiNii Articles, which is the largest academic database in Japan, we show that the extracted topics reflect the diversity of the research fields in the database. The experiment results also indicate the applicability of the proposed topic representation to the author disambiguation problem.

  • History-Pattern Encoding for Large-Scale Dynamic Multidimensional Datasets and Its Evaluations

    Masafumi MAKINO  Tatsuo TSUJI  Ken HIGUCHI  

     
    PAPER

      Pubricized:
    2016/01/14
      Vol:
    E99-D No:4
      Page(s):
    989-999

    In this paper, we present a new encoding/decoding method for dynamic multidimensional datasets and its implementation scheme. Our method encodes an n-dimensional tuple into a pair of scalar values even if n is sufficiently large. The method also encodes and decodes tuples using only shift and and/or register instructions. One of the most serious problems in multidimensional array based tuple encoding is that the size of an encoded result may often exceed the machine word size for large-scale tuple sets. This problem is efficiently resolved in our scheme. We confirmed the advantages of our scheme by analytical and experimental evaluations. The experimental evaluations were conducted to compare our constructed prototype system with other systems; (1) a system based on a similar encoding scheme called history-offset encoding, and (2) PostgreSQL RDBMS. In most cases, both the storage and retrieval costs of our system significantly outperformed those of the other systems.

  • A Meet-in-the-Middle Attack on Reduced-Round Kalyna-b/2b

    Riham ALTAWY  Ahmed ABDELKHALEK  Amr M. YOUSSEF  

     
    LETTER-Information Network

      Pubricized:
    2016/01/22
      Vol:
    E99-D No:4
      Page(s):
    1246-1250

    In this letter, we present a meet-in-the-middle attack on the 7-round reduced block cipher Kalyna-b/2b, which has been approved as the new encryption standard of Ukraine (DSTU 7624:2014) in 2015. According to its designers, the cipher provides strength to several cryptanalytic methods after the fifth and sixth rounds of the versions with block length of 128 and 256 bits, respectively. Our attack is based on the differential enumeration approach, where we carefully deploy a four-round distinguisher in the first four rounds to bypass the effect of the carry bits resulting from the prewhitening modular key addition. We also exploit the linear relation between consecutive odd and even indexed round keys, which enables us to attack seven rounds and recover all the round keys incrementally. The attack on Kalyna with 128-bit block has a data complexity of 289 chosen plaintexts, time complexity of 2230.2 and a memory complexity of 2202.64. The data, time and memory complexities of our attack on Kalyna with 256-bit block are 2233, 2502.2 and 2170, respectively.

  • Automatic Recognition of Mycobacterium Tuberculosis Based on Active Shape Model

    Chao XU  Dongxiang ZHOU  Tao GUAN  Yongping ZHAI  Yunhui LIU  

     
    PAPER-Pattern Recognition

      Pubricized:
    2016/01/08
      Vol:
    E99-D No:4
      Page(s):
    1162-1171

    This paper realized the automatic recognition of Mycobacterium tuberculosis in Ziehl-Neelsen stained images by the conventional light microscopy, which can be used in the computer-aided diagnosis of the tuberculosis. We proposed a novel recognition method based on active shape model. First, the candidate bacillus objects are segmented by a method of marker-based watershed transform. Next, a point distribution model of the object shape is proposed to label the landmarks on the object automatically. Then the active shape model is performed after aligning the training set with a weight matrix. The deformation regulation of the object shape is discovered and successfully applied in recognition without using geometric and other commonly used features. During this process, a width consistency constraint is combined with the shape parameter to improve the accuracy of the recognition. Experimental results demonstrate that the proposed method yields high accuracy in the images with different background colors. The recognition accuracy in object level and image level are 92.37% and 97.91% respectively.

  • FAQS: Fast Web Service Composition Algorithm Based on QoS-Aware Sampling

    Wei LU  Weidong WANG  Ergude BAO  Liqiang WANG  Weiwei XING  Yue CHEN  

     
    PAPER-Mathematical Systems Science

      Vol:
    E99-A No:4
      Page(s):
    826-834

    Web Service Composition (WSC) has been well recognized as a convenient and flexible way of service sharing and integration in service-oriented application fields. WSC aims at selecting and composing a set of initial services with respect to the Quality of Service (QoS) values of their attributes (e.g., price), in order to complete a complex task and meet user requirements. A major research challenge of the QoS-aware WSC problem is to select a proper set of services to maximize the QoS of the composite service meeting several QoS constraints upon various attributes, e.g. total price or runtime. In this article, a fast algorithm based on QoS-aware sampling (FAQS) is proposed, which can efficiently find the near-optimal composition result from sampled services. FAQS consists of five steps as follows. 1) QoS normalization is performed to unify different metrics for QoS attributes. 2) The normalized services are sampled and categorized by guaranteeing similar number of services in each class. 3) The frequencies of the sampled services are calculated to guarantee the composed services are the most frequent ones. This process ensures that the sampled services cover as many as possible initial services. 4) The sampled services are composed by solving a linear programming problem. 5) The initial composition results are further optimized by solving a modified multi-choice multi-dimensional knapsack problem (MMKP). Experimental results indicate that FAQS is much faster than existing algorithms and could obtain stable near-optimal result.

  • Autonomous Decentralized Semantic-Based Architecture for Dynamic Content Classification

    Khalid MAHMOOD  Asif RAZA  Madan KRISHNAMURTHY  Hironao TAKAHASHI  

     
    PAPER

      Vol:
    E99-B No:4
      Page(s):
    849-858

    The growing trends in Internet usage for data and knowledge sharing calls for dynamic classification of web contents, particularly at the edges of the Internet. Rather than considering Linked Data as an integral part of Big Data, we propose Autonomous Decentralized Semantic-based Content Classifier (ADSCC) for dynamic classification of unstructured web contents, using Linked Data and web metadata in Content Delivery Network (CDN). The proposed framework ensures efficient categorization of URLs (even overlapping categories) by dynamically mapping the changing user-defined categories to ontologies' category/classes. This dynamic classification is performed by the proposed system that mainly involves three main algorithms/modules: Dynamic Mapping algorithm, Autonomous coordination-based Inference algorithm, and Context-based disambiguation. Evaluation results show that the proposed system achieves (on average), the precision, recall and F-measure within the 93-97% range.

  • An On-Chip Monitoring Circuit with 51-Phase PLL-Based Frequency Synthesizer for 8-Gb/s ODR Single-Ended Signaling Integrity Analysis

    Pil-Ho LEE  Yu-Jeong HWANG  Han-Yeol LEE  Hyun-Bae LEE  Young-Chan JANG  

     
    BRIEF PAPER

      Vol:
    E99-C No:4
      Page(s):
    440-443

    An on-chip monitoring circuit using a sub-sampling scheme, which consists of a 6-bit flash analog-to-digital converter (ADC) and a 51-phase phase-locked loop (PLL)-based frequency synthesizer, is proposed to analyze the signal integrity of a single-ended 8-Gb/s octal data rate (ODR) chip-to-chip interface with a source synchronous clocking scheme.

  • Low-Temperature Activation in Boron Ion-Implanted Silicon by Soft X-Ray Irradiation

    Akira HEYA  Naoto MATSUO  Kazuhiro KANDA  

     
    PAPER-Semiconductor Materials and Devices

      Vol:
    E99-C No:4
      Page(s):
    474-480

    A novel activation method for a B dopant implanted in a Si substrate using a soft X-ray undulator was examined. As the photon energy of the irradiated soft X-ray approached the energy of the core level of Si 2p, the activation ratio increased. The effect of soft X-ray irradiation on B activation was remarkable at temperatures lower than 400°C. The activation energy of B activation by soft X-ray irradiation (0.06 eV) was lower than that of B activation by furnace annealing (0.18 eV). The activation of the B dopant by soft X-ray irradiation occurs at low temperature, although the activation ratio shows small values of 6.2×10-3 at 110°C. The activation by soft X-ray is caused not only by thermal effects, but also electron excitation and atomic movement.

  • Diamond Cellular Network —Optimal Combination of Small Power Basestations and CoMP Cellular Networks —

    Hidekazu SHIMODAIRA  Gia Khanh TRAN  Kei SAKAGUCHI  Kiyomichi ARAKI  Shinobu NANBA  Satoshi KONISHI  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:4
      Page(s):
    917-927

    Coordinated Multi-point (CoMP) transmission has long been known for its ability to improve cell edge throughput. However, in a CoMP cellular network, fixed CoMP clustering results in cluster edges where system performance degrades due to non-coordinated clusters. To solve this problem, conventional studies proposed dynamic clustering schemes. However, such schemes require a complex backhaul topology and are infeasible with current network technologies. In this paper, small power base stations (BSs) are introduced instead of dynamic clustering to solve the cluster edge problem in CoMP cellular networks. This new cell topology is called the diamond cellular network since the resultant cell structure looks like a diamond pattern. In our novel cell topology, we derive the optimal locations of small power base stations and the optimal resource allocation between the CoMP base station and small power base stations to maximize the proportional fair utility function. By using the proposed architecture, in the case of perfect user scheduling, a more than 150% improvement in 5% outage throughput is achieved, and in the case of successive proportional fair user scheduling, nearly 100% improvement of 5% outage throughput is achieved compared with conventional single cell networks.

  • Character-Position-Free On-Line Handwritten Japanese Text Recognition by Two Segmentation Methods

    Jianjuan LIANG  Bilan ZHU  Taro KUMAGAI  Masaki NAKAGAWA  

     
    PAPER-Pattern Recognition

      Pubricized:
    2016/01/06
      Vol:
    E99-D No:4
      Page(s):
    1172-1181

    The paper presents a recognition method of character-position-free on-line handwritten Japanese text patterns to allow a user to overlay characters freely without confirming previously written characters. To develop this method, we first collected text patterns written without wrist or elbow support and without visual feedback and then prepared large sets of character-position-free handwritten Japanese text patterns artificially from normally handwritten text patterns. The proposed method sets each off-stroke between real strokes as undecided and evaluates the segmentation probability by SVM model. Then, the optimal segmentation-recognition path can be effectively found by Viterbi search in the candidate lattice, combining the scores of character recognition, geometric features, linguistic context, as well as the segmentation scores by SVM classification. We test this method on variously overlaid sample patterns, as well as on the above-mentioned collected handwritten patterns, and verify that its recognition rates match those of the latest recognizer for normally handwritten horizontal Japanese text with no serious speed restriction in practical applications.

  • A Design of Vehicular GPS and LTE Antenna Considering Vehicular Body Effects

    Patchaikani SINDHUJA  Yoshihiko KUWAHARA  Kiyotaka KUMAKI  Yoshiyuki HIRAMATSU  

     
    PAPER-Antennas and Propagation

      Vol:
    E99-B No:4
      Page(s):
    894-904

    In this paper, a vehicular antenna design scheme that considers vehicular body effects is proposed. A wire antenna for the global positioning system (GPS) and long-term evolution (LTE) systems is implemented on a plastic plate and then mounted on a windshield of the vehicle. Common outputs are used to allow feed sharing. It is necessary to increase the GPS right-hand circularly polarization (RHCP) gain near the zenith and to reduce the axis ratio (AR). For LTE, we need to increase the horizontal polarization (HP) gain. In addition, for LTE, multiband characteristics are required. In order to achieve the specified performance, the antenna shape is optimized via a Pareto genetic algorithm (PGA). When an antenna is mounted on the body, antenna performance changes significantly. To evaluate the performance of an antenna with complex shape mounted on a windshield, a commercial electromagnetic simulator (Ansoft HFSS) is used. To apply electromagnetic results output by HFSS to the PGA algorithm operating in the MATLAB environment, a MATLAB-to-HFSS linking program via Visual BASIC (VB) script was used. It is difficult to carry out the electromagnetic analysis on the entire body because of the limitations of the calculating load and memory size. To overcome these limitations, we consider only that part of the vehicle's body that influences antenna performance. We show that a series of optimization steps can minimize the degradation caused by the vehicle`s body. The simulation results clearly show that it is well optimized at 1.575GHz for GPS, and 0.74 ∼ 0.79GHz and 2.11 ∼ 2.16GHz for LTE, respectively.

  • Fast Mode Decision Technique for HEVC Intra Prediction Based on Reliability Metric for Motion Vectors

    Chihiro TSUTAKE  Yutaka NAKANO  Toshiyuki YOSHIDA  

     
    PAPER-Image Processing and Video Processing

      Pubricized:
    2016/01/21
      Vol:
    E99-D No:4
      Page(s):
    1193-1201

    This paper proposes a fast mode decision technique for intra prediction of High Efficiency Video Coding (HEVC) based on a reliability metric for motion vectors (RMMV). Since such a decision problem can be regarded as a kind of pattern classification, an efficient classifier is required for the reduction of computation complexity. This paper employs the RMMV as a classifier because the RMMV can efficiently categorize image blocks into flat(uniform), active, and edge blocks, and can estimate the direction of an edge block as well. A local search for angular modes is introduced to further speed up the decision process. An experiment shows the advantage of our technique over other techniques.

3161-3180hit(16314hit)