• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.8 s.227
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• pp.1087-1092
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• 2004

Adhesion and friction forces influence adversely on performance and durability of MEMS. It has been reported that the adhesion and friction forces can be reduced with the introduction of micro surface bumps into the contacting interfaces. In this study experiments were conducted to investigate comparatively the effect of hemispherical and torus micro bumps on the adhesion and friction forces. It is confirmed that micro bumps reduce the adhesion and friction forces, and their effect is more pronounced with the bumps of smaller outer boundary radius. Moreover, the results shows that the torus bumps exhibit more rapid decrease of the adhesion and friction forces with the decrease in the outer boundary radius of bump than the hemispherical bumps. When the magnitude of adhesion force is same, the torus bumps generate smaller friction force than the hemispherical bumps. The usage of hemispherical and torus bumps to reduce the adhesion and friction forces in MEMS is discussed.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.111-122
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• 1985

The present study was performed to observe the ultrastructure of the integument of adult Paragonimus westermani. Dogs experimentally infected with 60 metacercariae of F. westermani were autopsied 4 months after the infection. Adult p. westermani were extracted from the dogs and the fine structure was studied by means of scanning and transmission electron microscope. The findings are as follows: 1. Scanning electron microscopic findings showed that the spines and the papillae are distributed at whole body surface but the well developed spines or papaillae are shown around the oral sucker and ventral sucker. 2. At the end of the body, excretory pore was found, the shape was irregular. 3. Transmission electron microscopic findings showed that plasma membrane, tegument, basal lamina, connective tissue, circular muscle layer, longitudinal muscle layer. nerve axon and tegumental cell were observed. 4. In higher magnification, plasma membrance and bar-shaped granules were found at the outer surface of the tegument.

• Korean Journal of Plant Taxonomy
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• v.47 no.4
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• pp.308-315
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• 2017

A new species, Corydalis bonghwaensis M. Kim & H. Jo, is described here. It is found on a mountain slope in Bongwha-gun, Gyeongsangbuk-do, Korea. Corydalis bonghwaensis shares several characteristics (white flowers, glabrous pedicels, white tubers, and the polygonal stigma) with related species C. namdoensis B. U. Oh & J. G. Kim and C. albipetala B. U. Oh. However, this new species has flowers which change from pale-yellow to white, a mucronated inner-petal apex, linear leaflets, and fusiform capsules with two-rowed seeds. In contrast, C. namdoensis has retuse inner-petal apex, various leaflets, and fusiform capsules with 2-rowed seeds. C. albipetala has retuse inner-petal apex, elliptical leaflets, and linear capsule with 1-rowed seeds. Also C. humilis B. U. Oh & Y. S. Kim has pale-blue purple flowers, elliptical leaflets, inflorescence with 1-5 flowers, and hemispherical lower-outer petal.