Hirotsugu Kojima

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In a series of exploratory studies to develop instruments for measuring field dependence in young children, a total of 312 Japanese middle-class children, ages 5 to 6, served as subjects. Without changing the essential nature of the original test, the geometric embedded-figures test attained relatively high internal consistency (KR-20 in the .80's) and(More)
Background: Multipoint observations of plasma waves are essential for separating spatial and temporal variations of a plasma turbulence. Miniaturization and high environmental (temperature and radiation) robustness are key requirements for scientific instrument design toward a sensor network consisting of palm-sized probes. With increasing these demands, a(More)
SUMMARY A sensor network consisting of a number of palm-sized nodes with small electric and magnetic sensors has been proposed to monitor local electromagnetic activities in space plasmas. In the present study, a compact loop antenna system is designed and fabricated for use in sensor nodes that can capture magnetic vector fields from ELF to MF frequencies.(More)
Most visible matter in the Universe exists as plasma. How this plasma is heated, and especially how the initial non-equilibrium plasma distributions relax to thermal equilibrium (as predicted by Maxwell-Boltzman statistics), is a fundamental question in studies of astrophysical and laboratory plasmas. Astrophysical plasmas are often so tenuous that binary(More)
—A software wave receiver was aboard the SS-520-2 rocket as a part of the plasma wave analyzer and successfully accomplished waveform observations and spectral observations. In the present paper, we describe the specifications and roles of the software wave receiver on the SS-520-2 rocket experiment. This receiver consists of a waveform receiver using(More)
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