• The Journal of the Korean dental association
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• v.14 no.11
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• pp.906-908
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• 1976

A case of pyogenic granuloma between left central lncisor and upper left lateral lncisor was observed in an 18year old Korean male. the characteristics were as follow 1) The side of the cuccerence was betweeb gum of the upper left central lncisor and that of the lateral lncisor. 2) It is bright red or purple red anf either friable or firm depending upon its duration in the majority of cases it presents surface ulceration and purulent exudation 3)Granuloma pyogenicum is similar in clinical and microscopic appearance to the conditioned gingival enlargement seen in pregnancy. Differencial diagnosis depends upon the patient's history.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.1 no.1
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• pp.101-108
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• 2002

In the grinding process, the degree of the sharpness in wheel gram affects the surface roughness and the dimensional accuracy. If a wheel with dull grains is used, the grinding force will be increased and the surface roughness deteriorated. To produce a precision component, the magnitude of parameters related to the wear amount of a grinding wheel has to be limited. In this study, a variation of the grinding force and the surface roughness were measured to seek the machining characteristics of the W A and CBN wheels. From the wear amount of the grinding wheel and the removal rate of workpiece, the grinding ratio was calculated. And also the wheel life was determined at a rapid decreasing point of the grinding ratio. The difference between the surface of wheel-workpiece before grinding and after wheel life was clearly verified with a microscopic photo.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.1
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• pp.77-83
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• 1997

In this paper, we have studied internal quality including chemical compositions, microscopic structure and nonmetalic inclusion of test materials. We have analyzed dynamic characteristics of cutting force of milling including tensile strength value, hardness etc. Test materials are used in the tempered carbon steel and the non-tempered carbon steel. The obtained results are as follows: 1. In analyzing internal quality, the tempered carbon steel have typical martensite structure and the non-tempered carbon steel have ferrite + pearlite structure. 2. Yield strength, tensile strength and hardness value are in the non-tempered carbon steel but elongation is maximum value in the tempered carbon steel. 3. Cutting force is smaller non-tempered carbon steel than tempered carbon steel when feed speed and depth on cut is constant. 4. Cutting force is smaller non-tempered carbon steel than tempered carbon steel when cutting speed and depth of cut is constant.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.12
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• pp.121-126
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• 1997

The use of CBN tool material has been greatly increased because of the superior metal cutting performance for the machining of hardened steel. This paper presents some experimental results on the ball endmiling of harened steels. Three different hardnesses of STD11 workpieces were machined using CBN ball endimills, and the machining characteristics including cutting forces tool wear, and surface roughness of machined surface were compared. It has been found that the CBN ball endmill works better in the machining of harder workpieces. The microscopic examination explains that this unusual phenomenon is caused by the difference of microstructure of each workpieces.

• Journal of the Korean Wood Science and Technology
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• v.35 no.2
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• pp.1-8
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• 2007

Frost ring formed in the secondary xylem of Pinus radiata was examined using various microscopic techniques. Cell walls in a frost ring were poorly developed, lacking in the proportion of wall components. Formation of secondary cell wall was imperfect and thickness of secondary wall was varied. Cytochemical examinations provided the evidence that the synthesis of structural polysaccharides and lignin was inhibited, resulting in the malformation of secondary cell walls. Judging by the highly irregular nature of the cell wall, it appears that cellulosic/hemicellulosic framework was affected and the template for lignification by frost.

• Journal of Chest Surgery
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• v.26 no.9
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• pp.722-725
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• 1993

Multiple primary lung cancer is a rare disease entity and its clinical characteristics, treatment, and prognosis are poorly described. But the multiple primary lung cancer have a more favorable prognosis than locally recurrent or metastastic disease. Therefore, appropriate identification of multiple primary lung cancer will be very important. We have experienced a case of stage I multiple primary lung cancer in a 76-year-old male with two large mass in the right lower lobe without metastasis in the mediastinal lymph nodes with right mid and lower lobectomy. The microscopic pictures revealed adenocarcinoma in the one & small cell carcinoma in another. The post-operative courses were in uneventful for 4 months & but he was treated with chemotherapies, 2 times for complete remission of small cell carcinoma to now after discharge.

• The Korean Journal of Mycology
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• v.45 no.3
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• pp.229-233
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• 2017

We isolated endophytic fungal strains from roots of Rhododendron schlippenbachii growing in Minjujisan mountain, Korea. The two strains were identified as Engyodontium album and Phaeosphaeria microscopica based on their morphological characteristics and sequence analysis of the internal transcribed spacer (ITS) and large subunit regions of the ribosomal DNA. These two species, E. album and P. microscopica, have not been previously reported in Korea.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.12
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• pp.3028-3044
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• 1993

A metallic bond of great strength for the same or dissimilar metals can be produced by the explosive welding. The formation of a metallic jet at the interface between the two impacting plates has been simulated using the numerical hydrocode DYNA2D. The mechanism of explosive welding for the wave formation is also analyzed by the computer simulation technique. The microscopic with the experimentally observed behaviour of the explosive welding. The computer simulations of the explosive welding process have proven especially useful for analyzing the mechanism of metallic bones.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.3
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• pp.90-96
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• 2001

Experimental investigations were carried out to find the characteristics of grinding of ceramics. Grinding mechanisms of ceramics were inspected through the microscopic examination. It has been found that the specific grinding energy of ceramics is relatively low as compared to that of steels. The specific grinding energy affects the surface roughness and the residual stress of ground surface. the experimental results indicate that the rougher surface finish and higher compressive residual stress are obtained at lower specific grinding energy. The surface roughness and the residual stress of the ground surface have significant effects on the strength of ground piece of ceramics.

• Journal of Nutrition and Health
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• v.23 no.7
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• pp.467-476
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• 1990

This study was performed to investigate the effects of different fat diets on the serum lipid composition and on the morphology of liver tissue of the spontaneously hypertensive rats(SHR), Rats were fed for 17 weeks one of four fat diets, control(corn oil : beef tallow=1:1), beef tallow, grapeseed oil and soybean oil. Blood was withdrawn by heart puncture from each SHR, and used to determine the serum levels of total cholesterol, HDL-cholesterol, trigly ceride and phospholipid. No significant difference in body weight was observed in all diet groups. the total serum cholesterol was significantly lower in SHR fed grapeseed oil than that of other groups. The cholesterol lowering effect of grapeseed oil seemed to results from its high contents of phytosterol and linoleic acid. Also, serum HDL-cholesterol, triglyceride and phospholipid contents were low in all the groups. photochemical microscopic observations of the liver tissue revealed the congestion of sinosoid which is regarded as the characteristics of SHR, but no significant difference was observed among the groups.