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  • 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.

  • 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.

  • The Relevance Dependent Infinite Relational Model for Discovering Co-Cluster Structure from Relationships with Structured Noise

    Iku OHAMA  Hiromi IIDA  Takuya KIDA  Hiroki ARIMURA  

     
    PAPER-Artificial Intelligence, Data Mining

      Pubricized:
    2016/01/13
      Vol:
    E99-D No:4
      Page(s):
    1139-1152

    Latent variable models for relational data enable us to extract the co-cluster structures underlying observed relational data. The Infinite Relational Model (IRM) is a well-known relational model for discovering co-cluster structures with an unknown number of clusters. The IRM assumes that the link probability between two objects (e.g., a customer and an item) depends only on their cluster assignment. However, relational models based on this assumption often lead us to extract many non-informative and unexpected clusters. This is because the underlying co-cluster structures in real-world relationships are often destroyed by structured noise that blurs the cluster structure stochastically depending on the pair of related objects. To overcome this problem, in this paper, we propose an extended IRM that simultaneously estimates denoised clear co-cluster structure and a structured noise component. In other words, our proposed model jointly estimates cluster assignment and noise level for each object. We also present posterior probabilities for running collapsed Gibbs sampling to infer the model. Experiments on real-world datasets show that our model extracts a clear co-cluster structure. Moreover, we confirm that the estimated noise levels enable us to extract representative objects for each cluster.

  • Autonomous Decentralized Database System Self Configuration Technology for High Response

    Carlos PEREZ-LEGUIZAMO  

     
    PAPER

      Vol:
    E99-B No:4
      Page(s):
    794-802

    In recent years, society has experienced several changes in its ways and methods of consuming. Nowadays, the diversity and the customization of products and services have provoked that the consumer needs continuously change. Hence, the database systems support e-business processes are required to be timeliness and adaptable to the changing preferences. Autonomous Decentralized Database System (ADDS), has been proposed in order to satisfy the enhanced requirements of current on-line e-business applications. Autonomy and decentralization of subsystems help to achieve short response times in highly competitive situations and an autonomous Coordination Mobile Agent (CMA) has been proposed to achieve flexibility in a highly dynamic environment. However, a problem in ADDS is as the number of sites increases, the distribution and harmonization of product information among the sites are turning difficult. Therefore, many users cannot be satisfied quickly. As a result, system timeliness is inadequate. To solve this problem, a self configuration technology is proposed. This technology can configure the system to the evolving situation dynamically for achieving high response. A simulation shows the effectiveness of the proposed technology in a large-scale system. Finally, an implementation of this technology is presented.

  • A Partitioning Parallelization with Hybrid Migration of MOEA/D for Bi-Objective Optimization on Message-Passing Clusters

    Yu WU  Yuehong XIE  Weiqin YING  Xing XU  Zixing LIU  

     
    LETTER-Numerical Analysis and Optimization

      Vol:
    E99-A No:4
      Page(s):
    843-848

    A partitioning parallelization of the multi-objective evolutionary algorithm based on decomposition, pMOEA/D, is proposed in this letter to achieve significant time reductions for expensive bi-objective optimization problems (BOPs) on message-passing clusters. Each sub-population of pMOEA/D resides on a separate processor in a cluster and consists of a non-overlapping partition and some extra overlapping individuals for updating neighbors. Additionally, sub-populations cooperate across separate processors by the hybrid migration of elitist individuals and utopian points. Experimental results on two benchmark BOPs and the wireless sensor network layout problem indicate that pMOEA/D achieves satisfactory performance in terms of speedup and quality of solutions on message-passing clusters.

  • 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.

  • 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.

  • Safety Evaluation for Upgraded Avionics System

    Chao ZHANG  Xiaomu SHI  

     
    LETTER-Reliability, Maintainability and Safety Analysis

      Vol:
    E99-A No:4
      Page(s):
    849-852

    Safety is the foremost requirement of avionics systems on aircraft. So far, avionics systems have evolved into an integrated system, i.e., integrated avionics system, and the derivative functions occur when the avionics systems are upgraded. However, the traditional safety analysis method is insufficient to be utilized in upgraded avionics systems due to these derivative functions. In this letter, a safety evaluation scheme is proposed to quantitatively evaluate the safety of the upgraded avionics systems. All the functions including the derivative functions can be traced and covered. Meanwhile, a set of safety issues based on different views is established to evaluate the safety capability from three layers, i.e., the mission layer, function layer and resource layer. The proposed scheme can be considered as an efficient scheme in the safety validation and verification in the upgraded avionics systems.

  • Dependency-Based Extraction of Conditional Statements for Understanding Business Rules

    Tomomi HATANO  Takashi ISHIO  Joji OKADA  Yuji SAKATA  Katsuro INOUE  

     
    PAPER-Software Engineering

      Pubricized:
    2016/01/08
      Vol:
    E99-D No:4
      Page(s):
    1117-1126

    For the maintenance of a business system, developers must understand the business rules implemented in the system. One type of business rules defines computational business rules; they represent how an output value of a feature is computed from the valid inputs. Unfortunately, understanding business rules is a tedious and error-prone activity. We propose a program-dependence analysis technique tailored to understanding computational business rules. Given a variable representing an output, the proposed technique extracts the conditional statements that may affect the computation of the output. To evaluate the usefulness of the technique, we conducted an experiment with eight developers in one company. The results confirm that the proposed technique enables developers to accurately identify conditional statements corresponding to computational business rules. Furthermore, we compare the number of conditional statements extracted by the proposed technique and program slicing. We conclude that the proposed technique, in general, is more effective than program slicing.

  • Time Synchronization Technique Using EPON for Next-Generation Power Grids

    Yuichi NAKAMURA  Andy HARVATH  Hiroaki NISHI  

     
    PAPER

      Vol:
    E99-B No:4
      Page(s):
    859-866

    Changing attitudes toward energy security and energy conservation have led to the introduction of distributed power systems such as photovoltaic, gas-cogeneration, biomass, water, and wind power generators. The mass installation of distributed energy generators often causes instability in the voltage and frequency of the power grid. Moreover, the power quality of distributed power grids can become degraded when system faults or the activation of highly loaded machines cause rapid changes in power load. To avoid such problems and maintain an acceptable power quality, it is important to detect the source of these rapid changes. To address these issues, next-generation power grids that can detect the fault location have been proposed. Fault location demands accurate time synchronization. Conventional techniques use the Global Positioning System (GPS) and/or IEEE 1588v2 for time synchronization. However, both methods have drawbacks — GPS cannot be used in indoor situations, and the installation cost of IEEE 1588v2 devices is high. In this paper, a time synchronization technique using the broadcast function of an Ethernet Passive Optical Network (EPON) system is proposed. Experiments show that the proposed technique is low-cost and useful for smart grid applications that use time synchronization in EPON-based next-generation power grids.

  • New Families of Binary Sequence Pairs with Three-Level Correlation and Odd Composite Length

    Xiuping PENG  Jiadong REN  Chengqian XU  Kai LIU  

     
    LETTER-Spread Spectrum Technologies and Applications

      Vol:
    E99-A No:4
      Page(s):
    874-879

    In this letter, several new families of binary sequence pairs with period N=np, where p is a prime and gcd(n,p)=1, and optimal correlation values 1 and -3 are constructed. These classes of binary sequence pairs are based on Chinese remainder theorem. The constructed sequence pairs have optimum balance among 0's and 1's.

  • Management and Technology Innovation in Rail Industry as Social Infrastructure for Improved Quality of Life Open Access

    Masaki OGATA  

     
    INVITED PAPER

      Vol:
    E99-B No:4
      Page(s):
    778-785

    East Japan Railway Company has created new businesses such as life-style business and information technology business on the basis of railway business for sustainable growth. These businesses generate and provide synergy to one another effectively because each business is autonomous decentralized system based on diversified infrastructure. The infrastructure includes not just structure but management, technology, operation and maintenance: we call this “MTOMI Model.” The MTOMI Model is the key concept of JR East's businesses and can generate JR East's ecosystem.

  • 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.

  • A Study on Dynamic Clustering for Large-Scale Multi-User MIMO Distributed Antenna Systems with Spatial Correlation

    Ou ZHAO  Hidekazu MURATA  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:4
      Page(s):
    928-938

    Distributed antenna systems (DASs) combined with multi-user multiple-input multiple-output (MU-MIMO) transmission techniques have recently attracted significant attention. To establish MU-MIMO DASs that have wide service areas, the use of a dynamic clustering scheme (CS) is necessary to reduce computation in precoding. In the present study, we propose a simple method for dynamic clustering to establish a single cell large-scale MU-MIMO DAS and investigate its performance. We also compare the characteristics of the proposal to those of other schemes such as exhaustive search, traditional location-based adaptive CS, and improved norm-based CS in terms of sum rate improvement. Additionally, to make our results more universal, we further introduce spatial correlation to the considered system. Computer simulation results indicate that the proposed CS for the considered system provides better performance than the existing schemes and can achieve a sum rate close to that of exhaustive search but at a lower computational cost.

  • 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.

  • BLM-Rank: A Bayesian Linear Method for Learning to Rank and Its GPU Implementation

    Huifeng GUO  Dianhui CHU  Yunming YE  Xutao LI  Xixian FAN  

     
    PAPER

      Pubricized:
    2016/01/14
      Vol:
    E99-D No:4
      Page(s):
    896-905

    Ranking as an important task in information systems has many applications, such as document/webpage retrieval, collaborative filtering and advertising. The last decade has witnessed a growing interest in the study of learning to rank as a means to leverage training information in a system. In this paper, we propose a new learning to rank method, i.e. BLM-Rank, which uses a linear function to score samples and models the pairwise preference of samples relying on their scores under a Bayesian framework. A stochastic gradient approach is adopted to maximize the posterior probability in BLM-Rank. For industrial practice, we have also implemented the proposed algorithm on Graphic Processing Unit (GPU). Experimental results on LETOR have demonstrated that the proposed BLM-Rank method outperforms the state-of-the-art methods, including RankSVM-Struct, RankBoost, AdaRank-NDCG, AdaRank-MAP and ListNet. Moreover, the results have shown that the GPU implementation of the BLM-Rank method is ten-to-eleven times faster than its CPU counterpart in the training phase, and one-to-four times faster in the testing phase.

  • Properties of Generalized Feedback Shift Registers for Secure Scan Design

    Hideo FUJIWARA  Katsuya FUJIWARA  

     
    LETTER-Dependable Computing

      Pubricized:
    2016/01/21
      Vol:
    E99-D No:4
      Page(s):
    1255-1258

    In our previous work [12], [13], we introduced generalized feed-forward shift registers (GF2SR, for short) to apply them to secure and testable scan design. In this paper, we introduce another class of generalized shift registers called generalized feedback shift registers (GFSR, for short), and consider the properties of GFSR that are useful for secure scan design. We present how to control/observe GFSR to guarantee scan-in and scan-out operations that can be overlapped in the same way as the conventional scan testing. Testability and security of scan design using GFSR are considered. The cardinality of each class is clarified. We also present how to design strongly secure GFSR as well as GF2SR considered in [13].

  • A Noise-Robust Positive-Feedback Floating-Gate Logic

    Luis F. CISNEROS-SINENCIO  Alejandro DIAZ-SANCHEZ  Jaime RAMIREZ-ANGULO  

     
    PAPER

      Vol:
    E99-C No:4
      Page(s):
    452-457

    Despite logic families based on floating-gate MOS (FGMOS) transistors achieve significant reductions in terms of power and transistor count, these logics have had little impact on VLSI design due to their sensitivity to noise. In order to attain robustness to this phenomenon, Positive-Feedback Floating-Gate logic (PFFGL) uses a differential architecture and positive feedback; data obtained from a 0.5µm ON Semiconductors test chip and from SPICE simulations shows PFFGL to be immune to noise from parasitic couplings as well as to leakage even when minimum device size is used.

4101-4120hit(20498hit)