The Experts below are selected from a list of 10743 Experts worldwide ranked by ideXlab platform

Takashi Hiyama - One of the best experts on this subject based on the ideXlab platform.

  • A New Protection Scheme for Fault Location and Relay by Matrix Operation Method in Transmission Lines
    2005 IEEE PES Transmission & Distribution Conference & Exposition: Asia and Pacific, 2005
    Co-Authors: Hidetsura Kuribayashi, T. Inagaki, K. Tsuji, Takashi Hiyama
    Abstract:

    This paper presents additional functions of the newly developed Matrix Operation type protection relay in power transmission lines. The paper presents the basic principle of fault location, the function of integrated protection, corresponding of the system configuration, the regular surveillance, and the results of simulation test. The general equations, which are utilized for the fault detection and the fault location, are derived from the basic equations based on the principle of Kirchhoff's first and second laws for the study transmission system. The proposed protection relay, differing from the conventional digital ones, enable to generalize the required protection functions such as the grounding fault protection, the short-circuit fault protection, the main and the backup protection based on a equivalent circuit for the study system. The function of regular surveillance can be realized to satisfy the voltage balance calculated by the off-line constants and the estimated on-line parameters synthetically. It ensures effectively the reliability of the proposed protection system. The new functions are developed naturally from the principles of the Matrix Operation type protection relay. Simulation studies and laboratory experiments have clarified the fact that the proposed protection scheme provides an innovative way to solve many problems still remained

  • A high-speed processing method for Matrix Operation type protection relay on power system
    IPEC 2003 - 6th International Power Engineering Conference, 2003
    Co-Authors: X. F. Zuo, Kouiti Tsuji, H. Kuribyashi, Hideaki Ohnishi, Takashi Hiyama
    Abstract:

    This paper presents a modified Matrix Operation type protection relay to achieve its real time implementation in considering the required computation time. An interpolation method has been proposed to improve the former Newton-Raphson's (NR's) approximate approach for solving the non-linear Matrix equations of proposed protection relay. The former NR's method has the advantages of the quite precise identification of fault locations. However, a heavy computation is required, therefore, its real time availability is the major concern in this paper. The performance of the proposed protection relay might be degraded because of its required relatively heavy computational burden for the iterative calculation including diagonal transformations and the inverse calculation of the corresponding Matrix. The practicality, i.e., mainly the real time availability, of the proposed protection relay has been demonstrated through the computer simulations. Moreover, the details of the proposed protection relay have been presented in this paper.

  • Development of Matrix Operation Type Protection Relay
    Ieej Transactions on Power and Energy, 2003
    Co-Authors: Xiaofei Zuo, Kouiti Tsuji, Hidetsura Kuribayashi, Takashi Hiyama
    Abstract:

    This paper presents a new digital type protection relay based on Matrix Operations. The basic principle of the Matrix Operation type protection scheme has been already discussed and investigated. However, further studies have been required especially to confirm the real time capability of the proposed scheme, in addition to evaluate the accuracy of fault detection and the identification of fault location. The off-line pre-calculation has been proposed for solving the time-consuming problem. Furthermore, the interpolation technique based non-iterative solution has been developed, which replaces the traditionally iterative Newton-Raphson's method for saving required calculation time. Combining both of the off-line pre-calculation and the interpolation method enables to ensure the activation time of the proposed protection relay within two cycles after a fault occurrence. Moreover, a high accuracy of fault detection can be achieved. In order to demonstrate the reliability of the proposed scheme, numerical simulations have been performed through using the actual data measured on real power systems with different voltage levels. The compared results indicate the highly precise estimation of the fault locations compared with the inspected fault locations on transmission lines. The required computation time is also estimated with considering types of numerical calculations included in the proposed algorithm. The estimated computation time is short enough for the real time implementation of the proposed scheme.

Elisa E. Konofagou - One of the best experts on this subject based on the ideXlab platform.

  • Sparse Matrix Beamforming and Image Reconstruction for 2-D HIFU Monitoring Using Harmonic Motion Imaging for Focused Ultrasound (HMIFU) With In Vitro Validation
    IEEE Transactions on Medical Imaging, 2014
    Co-Authors: Jean Provost, Julien Grondin, Shutao Wang, Fabrice Marquet, Ethan Bunting, Elisa E. Konofagou
    Abstract:

    Harmonic motion imaging for focused ultrasound (HMIFU) utilizes an amplitude-modulated HIFU beam to induce a localized focal oscillatory motion simultaneously estimated. The objective of this study is to develop and show the feasibility of a novel fast beamforming algorithm for image reconstruction using GPU-based sparse-Matrix Operation with real-time feedback. In this study, the algorithm was implemented onto a fully integrated, clinically relevant HMIFU system. A single divergent transmit beam was used while fast beamforming was implemented using a GPU-based delay-and-sum method and a sparse-Matrix Operation. Axial HMI displacements were then estimated from the RF signals using a 1-D normalized cross-correlation method and streamed to a graphic user interface with frame rates up to 15 Hz, a 100-fold increase compared to conventional CPU-based processing. The real-time feedback rate does not require interrupting the HIFU treatment. Results in phantom experiments showed reproducible HMI images and monitoring of 22 in vitro HIFU treatments using the new 2-D system demonstrated reproducible displacement imaging, and monitoring of 22 in vitro HIFU treatments using the new 2-D system showed a consistent average focal displacement decrease of 46.7 ±14.6% during lesion formation. Complementary focal temperature monitoring also indicated an average rate of displacement increase and decrease with focal temperature at 0.84±1.15%/°C, and 2.03±0.93%/°C, respectively. These results reinforce the HMIFU capability of estimating and monitoring stiffness related changes in real time. Current ongoing studies include clinical translation of the presented system for monitoring of HIFU treatment for breast and pancreatic tumor applications.

Kouiti Tsuji - One of the best experts on this subject based on the ideXlab platform.

  • Development of Matrix Operation Type Protection Relay
    Ieej Transactions on Power and Energy, 2003
    Co-Authors: Xiaofei Zuo, Kouiti Tsuji, Hidetsura Kuribayashi, Takashi Hiyama
    Abstract:

    This paper presents a new digital type protection relay based on Matrix Operations. The basic principle of the Matrix Operation type protection scheme has been already discussed and investigated. However, further studies have been required especially to confirm the real time capability of the proposed scheme, in addition to evaluate the accuracy of fault detection and the identification of fault location. The off-line pre-calculation has been proposed for solving the time-consuming problem. Furthermore, the interpolation technique based non-iterative solution has been developed, which replaces the traditionally iterative Newton-Raphson's method for saving required calculation time. Combining both of the off-line pre-calculation and the interpolation method enables to ensure the activation time of the proposed protection relay within two cycles after a fault occurrence. Moreover, a high accuracy of fault detection can be achieved. In order to demonstrate the reliability of the proposed scheme, numerical simulations have been performed through using the actual data measured on real power systems with different voltage levels. The compared results indicate the highly precise estimation of the fault locations compared with the inspected fault locations on transmission lines. The required computation time is also estimated with considering types of numerical calculations included in the proposed algorithm. The estimated computation time is short enough for the real time implementation of the proposed scheme.

  • A high-speed processing method for Matrix Operation type protection relay on power system
    IPEC 2003 - 6th International Power Engineering Conference, 2003
    Co-Authors: X. F. Zuo, Kouiti Tsuji, H. Kuribyashi, Hideaki Ohnishi, Takashi Hiyama
    Abstract:

    This paper presents a modified Matrix Operation type protection relay to achieve its real time implementation in considering the required computation time. An interpolation method has been proposed to improve the former Newton-Raphson's (NR's) approximate approach for solving the non-linear Matrix equations of proposed protection relay. The former NR's method has the advantages of the quite precise identification of fault locations. However, a heavy computation is required, therefore, its real time availability is the major concern in this paper. The performance of the proposed protection relay might be degraded because of its required relatively heavy computational burden for the iterative calculation including diagonal transformations and the inverse calculation of the corresponding Matrix. The practicality, i.e., mainly the real time availability, of the proposed protection relay has been demonstrated through the computer simulations. Moreover, the details of the proposed protection relay have been presented in this paper.

  • Principle of Matrix Operation type protection relays
    Proceedings of the IEEE Power Engineering Society Transmission and Distribution Conference, 2002
    Co-Authors: Xiaofei Zuo, Hidetsura Kuribayashi, Hiroshi Ohnishi, Kouiti Tsuji
    Abstract:

    The system protection relays, which protect the transmission facilities for electrical power transmission from power stations to customers, are severely required to minimize fault sections and operate promptly so that system disturbance at faults can be reduced. It has been researched and studied that the application of Operation theories to the system protection relays. It has been drawn the outlines of a new digital relay, which has vastly been improved in functionality. This papers reports the overview of the new digital relay. Kirchhoff's first and second laws are used together as a basic principle. Transmission line faults are exactly simulated for the six lines of double circuits facilities. As much information as possible about faults is utilized.

Hidetsura Kuribayashi - One of the best experts on this subject based on the ideXlab platform.

  • A New Protection Scheme for Fault Location and Relay by Matrix Operation Method in Transmission Lines
    2005 IEEE PES Transmission & Distribution Conference & Exposition: Asia and Pacific, 2005
    Co-Authors: Hidetsura Kuribayashi, T. Inagaki, K. Tsuji, Takashi Hiyama
    Abstract:

    This paper presents additional functions of the newly developed Matrix Operation type protection relay in power transmission lines. The paper presents the basic principle of fault location, the function of integrated protection, corresponding of the system configuration, the regular surveillance, and the results of simulation test. The general equations, which are utilized for the fault detection and the fault location, are derived from the basic equations based on the principle of Kirchhoff's first and second laws for the study transmission system. The proposed protection relay, differing from the conventional digital ones, enable to generalize the required protection functions such as the grounding fault protection, the short-circuit fault protection, the main and the backup protection based on a equivalent circuit for the study system. The function of regular surveillance can be realized to satisfy the voltage balance calculated by the off-line constants and the estimated on-line parameters synthetically. It ensures effectively the reliability of the proposed protection system. The new functions are developed naturally from the principles of the Matrix Operation type protection relay. Simulation studies and laboratory experiments have clarified the fact that the proposed protection scheme provides an innovative way to solve many problems still remained

  • Development of Matrix Operation Type Protection Relay
    Ieej Transactions on Power and Energy, 2003
    Co-Authors: Xiaofei Zuo, Kouiti Tsuji, Hidetsura Kuribayashi, Takashi Hiyama
    Abstract:

    This paper presents a new digital type protection relay based on Matrix Operations. The basic principle of the Matrix Operation type protection scheme has been already discussed and investigated. However, further studies have been required especially to confirm the real time capability of the proposed scheme, in addition to evaluate the accuracy of fault detection and the identification of fault location. The off-line pre-calculation has been proposed for solving the time-consuming problem. Furthermore, the interpolation technique based non-iterative solution has been developed, which replaces the traditionally iterative Newton-Raphson's method for saving required calculation time. Combining both of the off-line pre-calculation and the interpolation method enables to ensure the activation time of the proposed protection relay within two cycles after a fault occurrence. Moreover, a high accuracy of fault detection can be achieved. In order to demonstrate the reliability of the proposed scheme, numerical simulations have been performed through using the actual data measured on real power systems with different voltage levels. The compared results indicate the highly precise estimation of the fault locations compared with the inspected fault locations on transmission lines. The required computation time is also estimated with considering types of numerical calculations included in the proposed algorithm. The estimated computation time is short enough for the real time implementation of the proposed scheme.

  • Principle of Matrix Operation type protection relays
    Proceedings of the IEEE Power Engineering Society Transmission and Distribution Conference, 2002
    Co-Authors: Xiaofei Zuo, Hidetsura Kuribayashi, Hiroshi Ohnishi, Kouiti Tsuji
    Abstract:

    The system protection relays, which protect the transmission facilities for electrical power transmission from power stations to customers, are severely required to minimize fault sections and operate promptly so that system disturbance at faults can be reduced. It has been researched and studied that the application of Operation theories to the system protection relays. It has been drawn the outlines of a new digital relay, which has vastly been improved in functionality. This papers reports the overview of the new digital relay. Kirchhoff's first and second laws are used together as a basic principle. Transmission line faults are exactly simulated for the six lines of double circuits facilities. As much information as possible about faults is utilized.

Sun Wenbang - One of the best experts on this subject based on the ideXlab platform.

  • Research on 1-D SDCT Algorithm Based on Transform Basic Matrix
    2012 International Conference on Computer Science and Electronics Engineering, 2012
    Co-Authors: Zhou Maiyu, Wang Yong, Sun Wenbang
    Abstract:

    With the development of information processing technology, DCT has been used more and more widely and the research on DCT algorithm is very much too. But the physical performance of DCT is unclear. To overcome such drawbacks, the paper has proposed 1-D SDCT Operation method. First, some new 1-D Matrix Operation principles are defined. Then, the transform basic Matrix used for 1-D SDCT Operation was build and the Operation principle of 1-D SDCT is described in detail. Finally, the performance of 1-D SDCT was described systematically. The theoretical analysis shows that the proposed method makes DCT easy to comprehend and convenient to operate.

  • Research on Fast 2-D DCT Algorithm Based on Parallel Computing
    2011 International Conference on Network Computing and Information Security, 2011
    Co-Authors: Sun Wenbang, Chen Hexin, Sun Wenbing
    Abstract:

    Now, 2-D DCT is applied widely in the field of signal processing. But the transformation is operated by twice 1-D DCT successively, which limits the Operation efficiency to improve farther. To overcome such drawbacks, a new method based on parallel computing is proposed in the paper. First, a sort of new Matrix Operation algorithm and a new transformation Matrix are defined in the interest of convenient parallel computing. Then, 2-D DCT is operated integrally based on the new transformation Matrix and new Matrix Operation criterion. The theoretical analysis shows that the calculating amount of the proposed method to compute 2-D DCT only needs one equivalent multiplication and a few equivalent additions, and the Operation efficiency relative to other fast algorithms is improved notably.

  • Research on 3-D DCT Operation Based on Transformation Basic Matrix
    2011 International Conference on Multimedia and Signal Processing, 2011
    Co-Authors: Sun Wenbang, Chen Hexin, Chen Hong, Tang Haiyan
    Abstract:

    The 3-D DCT is different to be described by mathematical expression, and the transform is accomplished by computing 1-D DCT to each dimension of 3-D signal successively, which cannot embody the overall space character of 3-D transformation well. To overcome such drawbacks, a SDCT method was proposed in the paper. First, several 3-D Matrix Operation methods were defined, and the transformation basic Matrix was build. Then, the Operation principle of 3-D SDCT was described in detail. Finally, the 3-D SDCT Operational performance was described. The theoretical analysis shows that the SDCT makes 3-D DCT succinct to express, easy to comprehend and convenient to operate.

  • Research on 2-D SDCT method based on parallel computing
    2011 International Conference on Consumer Electronics Communications and Networks (CECNet), 2011
    Co-Authors: Sun Wenbang, Chen Hexin, Chen Hong, Wang Zhiqiang
    Abstract:

    Now, 2-D DCT is applied widely in the field of signal processing. But the transform is operated by twice 1-D DCT successively, which limits the Operation efficiency to improve farther. To overcome such drawbacks, a new method based on parallel computing is proposed in the paper. First, a sort of new Matrix Operation algorithm and a new transform Matrix are defined in the interest of convenient parallel computing. Then, 2-D SDCT is operated integrally based on the new transform Matrix and new Matrix Operation criterion. The theoretical analysis shows that the calculating amount of the proposed method to compute 2-D DCT only needs one equivalent multiplication and a few equivalent additions, and the Operation efficiency relative to other fast algorithms is improved notably.