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In recent years, the possibility of applying process bus technology in accordance with IEC 61850 and IEC 61869 standards for protection relay systems has been investigated as a method of reducing the bulk of metallic cables in the substation environment and to support the digital transformation of power grid field data. Conventional process bus system sampling synchronization is enabled using dedicated devices for synchronization control, and hence the system is highly dependent upon the dedicated devices, which causes challenges in the durability, reliability, and cost aspects. Therefore, in this paper, we propose a new configuration method for the process bus using a synchronous sampling scheme based upon oversampling and high‐speed publishing rate of the sampled value frame. Subsequently, we discuss the validity and efficacy of the proposed method. Moreover, we present the interoperability test results using prototype stand‐alone merging units and intelligent electric devices from three vendors. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

SUMMARY More and more dispersed power sources will be introduced to achieve a low-carbon society. However, many problems may occur as a result of excessive introduction in the current power system. For example, delays or failures of fault detection may occur due to a decline in protective relay sensitivity. This paper proposes a new system of protective relays for distribution lines using section switches with sensors to solve the problem. In addition, experimental results on the proposed system composed of Intelligent Electronic Devices based on IEC 61850 are presented. [ABSTRACT FROM AUTHOR]

For most architects, the effective design of three-dimensional space in two-dimensional media remains an ongoing conundrum. Kazuhiro Kojima, the founding partner of the C+A Tokyo (CAt) office, describes how he set out to tackle this through his creation of the pioneering Space Block system at the Kojima Laboratory in the Tokyo University of Science in 1994, a design tool that could capture and extract space. He describes its application and refinement in the development of two ensuing systems: Existing Space Blocks (ESBs) and Basic Space Blocks (BSBs). [ABSTRACT FROM AUTHOR]

The resolution conversion method using DCT is now the mainstream of image compression techniques. This paper extends the conventional method in which the inverse DCT with the same number of points as that of DCT (3 points) in the encoding is used, and generalizes the procedure. More precisely, the resolution conversion is made executable with conversion factors of not only integers but also rational numbers. Thus, a greater degree of freedom is provided in selecting the filter for controlling the image quality. As a result, resolution conversion with any rational number factor can be performed by the 3-point inverse DCT, and the filter characteristics can be selected according to the image properties. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 85(9): 58–68, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.1119 [ABSTRACT FROM AUTHOR]