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For the success of future missions to the Moon and other similar cosmic environments, understanding and utilization of the lunar regolith has become essential. However, due to the scarcity and unaffordability of real lunar regolith on Earth, a number of lunar regolith simulants (e.g., JSC-1; NASA) have been developed for experimental purposes. However, Korea does not have its own lunar regolith, even though the country is planning to actively pursue lunar and space missions in the 2020s. Thus, this study has been conducted to develop a Korean lunar simulant prototype via basic feasibility attempts (e.g., raw material selection, particle size and chemical composition simulation). Finally, the first prototype of Korea's own lunar simulant has been obtained, and denominated as KLS-1.

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When diagnosing damage to high-rise buildings during earthquakes, it is necessary to measure the displacement of each story. However, with respect to accuracy and cost, it is most reasonable to convert acceleration into displacement. In this study, shake table testing was carried out to verify the conversion methods, converting the acceleration data measured in a high-rise building into velocity and displacement. In the shaking table test, the displacement of a 10-story model building under strong motion was measured using high-speed imaging devices. High-speed images were taken at 1000 frames per second, reflecting the dynamic behavior of the model building. Then, this displacement was compared with the displacement obtained by processing the acceleration data. This study applied three methods for correcting and converting acceleration into velocity and displacement. Method 1 used the transfer function, H2ω, which reflects the dynamic characteristics of the system. The displacements converted by this method showed the lowest accuracy, because the transfer function depends on the dynamic characteristics of the structure. Method 2 used the cosine Fourier transform for baseline correction, and the discrete input data are calculated as the sum of the cosine functions. Method 3 used the least-squares fitting in the first step to remove the linear drift in the acceleration and applied the high-pass Butterworth filter. The displacements converted by Method 2 were the most reliable, and were close to the displacements measured in the shaking table test. However, the response of high-rise buildings is affected by low- and high-frequency noise. It is necessary to further investigate the limitations and applicability of the conversion methods for providing reliable displacement of the building.