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10881-10900hit(42807hit)

  • Hand Gesture Recognition Based on Perceptual Shape Decomposition with a Kinect Camera

    Chun WANG  Zhongyuan LAI  Hongyuan WANG  

     
    LETTER-Pattern Recognition

      Vol:
    E96-D No:9
      Page(s):
    2147-2151

    In this paper, we propose the Perceptual Shape Decomposition (PSD) to detect fingers for a Kinect-based hand gesture recognition system. The PSD is formulated as a discrete optimization problem by removing all negative minima with minimum cost. Experiments show that our PSD is perceptually relevant and robust against distortion and hand variations, and thus improves the recognition system performance.

  • Neighborhood Level Error Control Codes for Multi-Level Cell Flash Memories

    Shohei KOTAKI  Masato KITAKAMI  

     
    PAPER

      Vol:
    E96-D No:9
      Page(s):
    1926-1932

    NAND Flash memories are widely used as data storages today. The memories are not intrinsically error free because they are affected by several physical disturbances. Technology scaling and introduction of multi-level cell (MLC) has improved data density, but it has made error effect more significant. Error control codes (ECC) are essential to improve reliability of NAND Flash memories. Efficiency of codes depends on error characteristic of systems, and codes are required to be designed to reflect this characteristic. In MLC Flash memories, errors tend to direct values to neighborhood. These errors are a class of M-ary asymmetric symbol error. Some codes which reflect the asymmetric property were proposed. They are designed to correct only 1 level shift errors because almost all of the errors in the memories are in such errors. But technology scaling, increase of program/erase (P/E) cycles, and MLC storing the large number of bits can cause multiple-level shift. This paper proposes single error control codes which can correct an error of more than 1 levels shift. Because the number of levels to be corrected is selectable, we can fit it into noise magnitude. Furthermore, it is possible to add error detecting function for error of the larger shift. Proposed codes are equivalent to a conventional integer codes, which can correct 1 level shift, on a certain parameter. Therefore, the codes are said to be generalization of conventional integer codes. Evaluation results show information lengths to respective check symbol lengths are larger than nonbinary Hamming codes and other M-ary asymmetric symbol error correcting codes.

  • Speaker Adaptation Based on PARAFAC2 of Transformation Matrices for Continuous Speech Recognition

    Yongwon JEONG  Sangjun LIM  Young Kuk KIM  Hyung Soon KIM  

     
    LETTER-Speech and Hearing

      Vol:
    E96-D No:9
      Page(s):
    2152-2155

    We present an acoustic model adaptation method where the transformation matrix for a new speaker is given by the product of bases and a weight matrix. The bases are built from the parallel factor analysis 2 (PARAFAC2) of training speakers' transformation matrices. We perform continuous speech recognition experiments using the WSJ0 corpus.

  • A Delivery Format for Unified Stereoscopic Video Content Transmissions over Dynamic Adaptive Streaming Scheme

    Jangwon LEE  Kugjin YUN  Doug Young SUH  Kyuheon KIM  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E96-D No:9
      Page(s):
    2162-2165

    This letter proposes a new delivery format in order to realize unified transmissions of stereoscopic video contents over a dynamic adaptive streaming scheme. With the proposed delivery format, various forms of stereoscopic video contents regardless of their encoding and composition types can be delivered over the current dynamic adaptive streaming scheme. In addition, the proposed delivery format supports dynamic and efficient switching between 2D and 3D sequences in an interoperable manner for both 2D and 3D digital devices, regardless of their capabilities. This letter describes the designed delivery format and shows dynamic interoperable applications for 2D and 3D mixed contents with the implemented system in order to verify its features and efficiency.

  • Layer-Aware FEC Based Scalable Multiple Description Coding for Robust Video Transmission over Path Diversity Networks

    Dinh Trieu DUONG  Deepak Kumar SINGH  Seok Ho WON  Doug Young SUH  

     
    PAPER-Multimedia Systems for Communications

      Vol:
    E96-B No:9
      Page(s):
    2323-2332

    In this paper, we propose a novel layered scalable- multiple description coding (LS-MDC) which offers the benefits of both scalable video coding and multiple description coding for robust video transmission over packet lossy networks. In the proposed LS-MDC method, multiple descriptions including base layer, enhancement layers, and their corresponding FEC parity data are allocated into two network paths of a path diversity system. Unlike the conventional approaches, the source base/enhancement data and their own parities in the proposed method are not transmitted together but are transferred over different paths. Therefore, the effect of burst packet losses can be effectively reduced for the descriptions. Furthermore, in order to minimize the overall distortion for the LS-MDC system and exploit the benefits of path diversity, we also propose an optimal rate allocation scheme that can adaptively control the transmission rate as well as the channel coding rate for media senders. Experiments show that the proposed method provides much better peak signal-to-noise ratio (PSNR) than conventional MDC techniques.

  • Fretting Characteristics of Dissimilar Metal Contacts

    Tetsuya ITO  Takuya YAMANAKA  Yasuhiro HATTORI  

     
    PAPER

      Vol:
    E96-C No:9
      Page(s):
    1104-1109

    The authors previously conducted the observation of microstructures and three-dimensional SEM on fretting wear phenomena at tin-plated contacts. In this study, we report the fretting characteristics of dissimilar metal contacts by studying the relation between the contact resistance behaviors and micro structural changes of gold and tin-plated fretting contacts, through surface SEM observations and cross sectional SEM and AES analysis.

  • A Test Compaction Oriented Don't Care Identification Method Based on X-bit Distribution

    Hiroshi YAMAZAKI  Motohiro WAKAZONO  Toshinori HOSOKAWA  Masayoshi YOSHIMURA  

     
    PAPER

      Vol:
    E96-D No:9
      Page(s):
    1994-2002

    In recent years, the growing density and complexity of VLSIs have led to an increase in the numbers of test patterns and fault models. Test patterns used in VLSI testing are required to provide high quality and low cost. Don't care (X) identification techniques and X-filling techniques are methods to satisfy these requirements. However, conventional X-identification techniques are less effective for application-specific fields such as test compaction because the X-bits concentrate on particular primary inputs and pseudo primary inputs. In this paper, we propose a don't care identification method for test compaction. The experimental results for ITC'99 and ISCAS'89 benchmark circuits show that a given test set can be efficiently compacted by the proposed method.

  • Fault Diagnosis and Reconfiguration Method for Network-on-Chip Based Multiple Processor Systems with Restricted Private Memories

    Masashi IMAI  Tomohiro YONEDA  

     
    PAPER

      Vol:
    E96-D No:9
      Page(s):
    1914-1925

    We propose a fault diagnosis and reconfiguration method based on the Pair and Swap scheme to improve the reliability and the MTTF (Mean Time To Failure) of network-on-chip based multiple processor systems where each processor core has its private memory. In the proposed scheme, two identical copies of a given task are executed on a pair of processor cores and the results are compared repeatedly in order to detect processor faults. If a fault is detected by mismatches, the fault is identified and isolated using a TMR (Triple Module Redundancy) and the system is reconfigured by the redundant processor cores. We propose that each task is quadruplicated and statically assigned to private memories so that each memory has only two different tasks. We evaluate the reliability of the proposed quadruplicated task allocation scheme in the viewpoint of MTTF. As a result, the MTTF of the proposed scheme is over 4.3 times longer than that of the duplicated task allocation scheme.

  • Optimal Trigger Time of Software Rejuvenation under Probabilistic Opportunities

    Hiroyuki OKAMURA  Tadashi DOHI  

     
    PAPER

      Vol:
    E96-D No:9
      Page(s):
    1933-1940

    This paper presents the opportunity-based software rejuvenation policy and the optimization problem of software rejuvenation trigger time maximizing the system performance index. Our model is based on a basic semi-Markov software rejuvenation model by Dohi et al. 2000 under the environment where possible time, called opportunity, to execute software rejuvenation is limited. In the paper, we consider two stochastic point processes; renewal process and Markovian arrival process to represent the opportunity process. In particular, we derive the existence condition of the optimal trigger time under the two point processes analytically. In numerical examples, we illustrate the optimal design of the rejuvenation trigger schedule based on empirical data.

  • On Detecting Delay Faults Using Time-to-Digital Converter Embedded in Boundary Scan

    Hiroyuki YOTSUYANAGI  Hiroyuki MAKIMOTO  Takanobu NIMIYA  Masaki HASHIZUME  

     
    PAPER

      Vol:
    E96-D No:9
      Page(s):
    1986-1993

    This paper proposes a method for testing delay faults using a boundary scan circuit in which a time-to-digital converter (TDC) is embedded. The incoming transitions from the other cores or chips are captured at the boundary scan circuit. The TDC circuit is modified to set the initial value for a delay line through which the transition is propagated. The condition for measuring timing slacks of two or more paths is also investigated since the overlap of the signals may occur in the delay line of the TDC in our boundary scan circuit. An experimental IC with the TDC and boundary scan is fabricated and is measured to estimate the delay of some paths measured by the TDC embedded in boundary scan cells. The simulation results for a benchmark circuit with the boundary scan circuit are also shown for the case that timing slacks of multiple paths can be observed even if the signals overlap in the TDC.

  • Improved Transmit and Detection Scheme for Hybrid STBC in MIMO-OFDM Systems

    Eui-Young LEE  Hyoung-Kyu SONG  

     
    LETTER-Information Network

      Vol:
    E96-D No:9
      Page(s):
    2131-2134

    The conventional hybrid STBC schemes can achieve less BER performance for STBC detection schemes than conventional STBC schemes since SM symbols interfere with STBC symbols. Therefore, this letter proposes the improved scheme for hybrid STBC systems. STBC and SM schemes are combined for the hybrid space-time block code system. Our approach effectively obtains both diversity gain and spectral efficiency gain. The proposed scheme offers improved BER performance since it uses iterative detection. Moreover, it increases the data rate effectively with a little performance loss.

  • Experimental Analysis of Arc Waveform Affected by Holder Temperature Change at Slowly Separation of Silver-Tin Dioxide Contacts

    Yoshiki KAYANO  Kazuaki MIYANAGA  Hiroshi INOUE  

     
    PAPER

      Vol:
    E96-C No:9
      Page(s):
    1110-1118

    Arc discharge at breaking electrical contact is considered as a main source of not only degradation of the electrical property but also an undesired electromagnetic (EM) noise. In order to clarify the effect of holder temperature on the bridge and arc-duration, opening-waveforms at slowly separating silver-tin dioxide contact with different holder temperature are measured and discussed experimentally in this paper. Firstly, as opening-waveforms, the contact voltage, the contact current and the movement of moving contact related to the gap length are measured simultaneously. Secondly, the relationship between temperature of the holder and duration of the arc was quantified experimentally. It was revealed that as the initial temperature of the holder becomes higher, arc-duration becomes slightly longer. More importantly, the holder temperature dependencies of percentage of each-phase (metallic and gaseous-phases) are different with different closed-current.

  • Synchronization of Two Different Unified Chaotic Systems with Unknown Mismatched Parameters via Sum of Squares Method

    Cheol-Joong KIM  Dongkyoung CHWA  

     
    PAPER-Nonlinear Problems

      Vol:
    E96-A No:9
      Page(s):
    1840-1847

    This paper proposes the synchronization control method for two different unified chaotic systems with unknown mismatched parameters using sum of squares method. Previously, feedback-linearizing and stabilization terms were used in the controller for the synchronization problem. However, they used just a constant matrix as a stabilization control gain, whose performance is shown to be valid only for a linear model. Thus, we propose the novel control method for the synchronization of the two different unified chaotic systems with unknown mismatched parameters via sum of squares method. We design the stabilization control input which is of the polynomial form by sum of squares method and also the adaptive law for the estimation of the unknown mismatched parameter between the master and slave systems. Since we can use the polynomial control input which is dependent on the system states as the stabilization controller, the proposed method can have better performance than the previous methods. Numerical simulations for both uni-directional and bi-directional chaotic systems show the validity and advantage of the proposed method.

  • A Capacity-Aware Thread Scheduling Method Combined with Cache Partitioning to Reduce Inter-Thread Cache Conflicts

    Masayuki SATO  Ryusuke EGAWA  Hiroyuki TAKIZAWA  Hiroaki KOBAYASHI  

     
    PAPER-Computer System

      Vol:
    E96-D No:9
      Page(s):
    2047-2054

    Chip multiprocessors (CMPs) improve performance by simultaneously executing multiple threads using integrated multiple cores. However, since these cores commonly share one cache, inter-thread cache conflicts often limit the performance improvement by multi-threading. This paper focuses on two causes of inter-thread cache conflicts. In shared caches of CMPs, cached data fetched by one thread are frequently evicted by another thread. Such an eviction, called inter-thread kickout (ITKO), is one of the major causes of inter-thread cache conflicts. The other cause is capacity shortage that occurs when one cache is shared by threads demanding large cache capacities. If the total capacity demanded by the threads exceeds the actual cache capacity, the threads compete to use the limited cache capacity, resulting in capacity shortage. To address inter-thread cache conflicts, we must take into account both ITKOs and capacity shortage. Therefore, this paper proposes a capacity-aware thread scheduling method combined with cache partitioning. In the proposed method, inter-thread cache conflicts due to ITKOs and capacity shortage are decreased by cache partitioning and thread scheduling, respectively. The proposed scheduling method estimates the capacity demand of each thread with an estimation method used in the cache partitioning mechanism. Based on the estimation used for cache partitioning, the thread scheduler decides thread combinations sharing one cache so as to avoid capacity shortage. Evaluation results suggest that the proposed method can improve overall performance by up to 8.1%, and the performance of individual threads by up to 12%. The results also show that both cache partitioning and thread scheduling are indispensable to avoid both ITKOs and capacity shortage simultaneously. Accordingly, the proposed method can significantly reduce the inter-thread cache conflicts and hence improve performance.

  • Locality-Constrained Multi-Task Joint Sparse Representation for Image Classification

    Lihua GUO  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E96-D No:9
      Page(s):
    2177-2181

    In the image classification applications, the test sample with multiple man-handcrafted descriptions can be sparsely represented by a few training subjects. Our paper is motivated by the success of multi-task joint sparse representation (MTJSR), and considers that the different modalities of features not only have the constraint of joint sparsity across different tasks, but also have the constraint of local manifold structure across different features. We introduce the constraint of local manifold structure into the MTJSR framework, and propose the Locality-constrained multi-task joint sparse representation method (LC-MTJSR). During the optimization of the formulated objective, the stochastic gradient descent method is used to guarantee fast convergence rate, which is essential for large-scale image categorization. Experiments on several challenging object classification datasets show that our proposed algorithm is better than the MTJSR, and is competitive with the state-of-the-art multiple kernel learning methods.

  • Reference-Independent Prosody Evaluation Based on Prosodic Unit Segmentation

    Sixuan ZHAO  Soo Ngee KOH  Kang Kwong LUKE  

     
    LETTER-Educational Technology

      Vol:
    E96-D No:9
      Page(s):
    2143-2146

    This paper proposes prosodic unit based segmentation for prosody evaluation by using pitch accent detection and forced alignment techniques. Support Vector Machine (SVM) is used to evaluate the prosody of non-native English speakers without reference utterances. Experimental results show the superiority of prosodic unit segmentation over word segmentation in terms of classification accuracy and dimension of the feature vectors used by SVM.

  • Degrees of Freedom of the MIMO K-way Relay Channel with Fractional Signal Space Alignment

    Bofeng YUAN  Xuewen LIAO  Xinmin LUO  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E96-B No:9
      Page(s):
    2281-2292

    The multiple-input-multiple-output (MIMO) Gaussian wireless network with K users and an intermediate relay is investigated. In this network, each user with available local channel state information (CSI) intends to convey a multicast message to all other users while receiving all messages from other users via the relay. This model is termed the MIMO K-way relay channel with distributed CSI. For this channel, the sum capacity is shown as MK/(K-1)log(SNR)+o(SNR) where each user and the relay is equipped with M antennas. Achievability is based on the signal space alignment strategy with a K-1 time slot extension. A most general case is then considered, in which each user intends to recover all messages required within T time slots. We provide an improved scheme called fractional signal space alignment which achieves MK/(K-1) degrees of freedom in the general case and the feasibility condition is also explored.

  • Positions of Arc Spots of Break Arcs Occurring between Carbon Contacts When Transverse Magnetic Field Is Applied

    Tomoaki SASAKI  Junya SEKIKAWA  

     
    BRIEF PAPER

      Vol:
    E96-C No:9
      Page(s):
    1138-1141

    Break arcs are generated between carbon contacts in a DC48V and 10A resistive circuit. The external transverse magnetic field formed by a permanent magnet is applied to break arcs. The position of the cathode spot region of the break arcs occurring between carbon contacts is investigated and the following results are shown. The cathode and anode spot regions moves together with and without the magnetic field. The position of the break arcs just before arc extinction tends to shift upward with increase of the magnetic flux density of the transverse magnetic field.

  • Development of RFID Antenna for Detection of Urination

    Hiromasa NAKAJIMA  Masaharu TAKAHASHI  Kazuyuki SAITO  Koichi ITO  

     
    PAPER-Antennas and Propagation

      Vol:
    E96-B No:9
      Page(s):
    2244-2250

    This paper introduces a radio frequency identification (RFID) tag for urination detection. The proposed tag is embedded into paper diapers in order to detect the patient's urination immediately. For this tag, we designed an RFID tag antenna at 950MHz, which matches the impedance of the associated integrated circuit (IC) chip. In addition, we calculate the antenna characteristics and measure the reflection coefficient (S11) and radiation pattern of the antenna. The results show that this system can be used to detect urination.

  • Techniques of Electromagnetic Compatibility Model Synthesis Based on On-Site Measurement Data

    Gaosheng LI  Peiguo LIU  Yan LI  Zhonghao LU  Dongming ZHOU  Yujian QIN  

     
    PAPER-Electromagnetic Compatibility(EMC)

      Vol:
    E96-B No:9
      Page(s):
    2251-2260

    Regular on-site testing is an elementary means to obtain real-time data and state of Electromagnetic Compatibility (EMC) of electronics systems. Nowadays, there is a lot of measured EMC data while the application of the data is insufficient. So we put forward the concept of EMC model synthesis. To carry out EMC data mining with measured electromagnetic data, we can build or modify models and synthesize variation rules of electromagnetic parameters of equipment and EMC performance of systems and platforms, then realize the information synthesis and state prediction. The concept of EMC reliability is brought forward together with the definition and description of parameters such as invalidation rate and EMC lifetime. We studied the application of statistical algorithms and Artificial Neural Network (ANN) in model synthesis. Operating flows and simulation results as well as measured data are presented. Relative research can support special measurement, active management and predictive maintenance and replenishment in the area of EMC.

10881-10900hit(42807hit)