• Journal of the Korean earth science society
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• v.42 no.2
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• pp.175-184
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• 2021

Fold axis of fold, a representative ductile deformation structure, is important for collecting information on the 3D fold structure and the orientation of maximum horizontal principal stress at the time of deformation. For this reason, several fold axis measurement methods based on the fold-related structural elements have been suggested and used even in areas where it is impossible to measure it directly. Thus, these various measurement methods are briefly introduced here, and the measured data with different methods are compared to estimate these methods' reliability. For this purpose, we acquired fold axes at six sites across the Manhang formation of the Pyeongan supergroup and limestones of the Joseon supergroup in Danyang, Chungcheongbuk-do, where fold structures are well developed. The data from the different methods are generally consistent, indicating practical applicability. Most of the fold axes from the measured sites show NNNE or NE trends indicating WNW-ESE or NW-SE trending maximum horizontal principal stress, except for the one site with a WNW trend. The WNW-ESE trending fold axis might be related to a different orogeny or secondary folding. The minor difference in the trends between N-NNE and NE was interpreted as being due to different scale; however, further research is needed to confirm this.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.5
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• pp.410-416
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• 2001

KLN thin films were fabricated on Pt coated Si(100) wafer using an rf-magnetron sputtering method. The grown KLN thin film consists of 4-fold grains. In this experiment, the structure of 4-fold grained thin film was investigated using XRD and SEM measurements. Pt layer was also deposited using the rf-magnetron sputtering method,. XRD measurement showed that he Pt thin film has Gaussian distribution form with strong (111) direction orientation. The KLN thin film has preferred-orientation of (001) direction, and the peak consists of 2 separate peaks; one with broad FWHM and the other with narrow FWHM. The sharp peak is due to single crystal, and combining with Em results, the 4-fold grain consists of singel crystals with c-axis normal to substrate.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.8
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• pp.21-28
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• 2008

Fizeau interferometer is used for inspecting the lens surface profile accurately. This study is focused on the design and optical measuring techniques for large optical components, such as a reflection mirror for large area lithography or astronomical purpose. A tower type Fizeau interferometer is designed and set up in horizontally with a 45$^{\circ}$ fold mirror which makes easy to align the optical path of heavy interferometer system. To align the optical path, a five-axes stage for the interferometer is required. This study shows a method of the 45$^{\circ}$ fold mirror alignment by using a three-axis stage instead of adjusting the interferometer itself or measuring object. This system will be installed on the large optics polishing machine during the manufacturing process as an on-machine inspection system.