• Biomolecules & Therapeutics
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• 제5권3호
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• pp.265-271
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• 1997

Since the advent of chemotherapy, certain types of cancer have been particularly resistant to chemotherapeutic treatment. One of the most well-studied types of resistance is resistance to multiple struc-turally dissimialr hydrophobic chemotherapeutic agents, or multidrug resistance (MDR). We found that MDR cells (KBV20C, KB7D) being highly resistant to colchicine, etoposide, and vincristine were found to have very low level of putrescine and low level of spermidine than the drug sensitive parental cells (KB) but they had almost same level of spermine as the drug sensitive cells. Although both MDR and drug sensitive cells had almost same rate of polyamine uptake, MDR cells were much more sensitive to an inhibitor of polyamine synthesis, methylglyoxal-bis guanylhydrazone (MGBG), suggesting that MDR cells might be defective in polyamine synthesis. These results also suggest that HGBG can be used for treatment of MDR in vivo.

• 소성∙가공
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• 제21권3호
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• pp.195-201
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• 2012

A vacuum ladling die casting system is suggested as a means to obtain a high vacuum level. A high vacuum of 17.8 mmHg is obtained by sealing the inner space of the mould. The sample product is a rear-head housing for an auto-compressor, and the die-casting with 6-cavities was conducted. The flow analysis shows that the filling speed during vacuum ladling is faster than for a non-vacuum system. The air holes in the sample product were too small to be seen with the naked eye in X-ray films. Density tests show that the high vacuum ladling system reduces the internal porosity as much as 57.8% when compared to the non-vacuum system. A defective rate of only 0.17% was found from leak testing. The results of this research prove that the high vacuum die-casting process is useful for manufacturing of aluminium components under high internal pressure.

• 대한치과의사협회지
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• 제25권9호통권220호
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• pp.847-854
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• 1987

Genioplasty may considerably change a person's face which needs surgical correction of deformed chin. Comprehensive treatment planning is therefore decisive for the treatment to be successful. A three-dimensional analysis of chin relative to cranial base, upper and lower jaws using the frontal and lateral facial photographs and cephalographs permits classification of the defective chin position and provides a basis for operation planning and deciding upon the operation method. A chin miniplate system has been developed for intraoperative registration securing the sagittal, vertical and horizontal position of the osteotomized chin and ould reduce the relapse rate.

• 한국전자통신학회논문지
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• 제6권4호
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• pp.517-522
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• 2011

수작업에 의한 기존의 프로젝션(projection) 용접시스템은 작업자의 부주의로 인한 불량이 자주 발생한다. 본 논문에서는 비전카메라를 사용하여 부품과 제품의 인식, 용접 및 수량 관리를 자동으로 수행하는 프로젝션 용접시스템을 제안한다. 제안 시스템은 비전카메라를 사용하여 용접에 사용되는 부품의 유무와 놓인 상태를 검사한다. 그리고 부품의 용접 후에는 제품 수량 카운터와 드레싱 등의 항목을 자동 갱신한다. 기존 시스템과의 비교 실험을 통해 불량률을 감소시키고 생산성을 높일 수 있음을 보인다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.506-507
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• 1992

When it comes to the 'Leak Detector System' generally, our country has a large income 'Rotary Type Leak Detector' of foreign goods. The completed development of the 'Line Type Leak-Detector' system was produced to check Whether the containers for small and large on the filling line are auto defective. This system is applied to the filling package Processing during the production and contributed to inproving competiveness of domestic containers manufactures of all society of Industry. Also, high precision and realiablity, very compact size, low cost and Easy set-up etc. by checking the experimental data directly plan, Design and making for '1 Compression Head Control Leak Detector System'. This flexcible system can be equipped with multiple Compression heads depending on the requested prodution test rate and test precision.

• 산업공학
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• 제21권3호
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• pp.302-311
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• 2008

Efficiency evaluation methods of manufacturing processes have relied on absolute measures such as defective rate and throughput per person, ignoring various process characteristics. To overcome the limitation, we propose an evaluation model which reflects characteristics of each process. It is composed of three measures : utilization, performance, and improvement. The suggested model utilizes a combination of DEA and AHP methods. The proposed method has been applied to efficiency evaluation of cellular phone case manufacturing processes.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.172-175
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• 2008

In the last five years, 45 people died and 104 were wounded because of carbon monoxide poisoning accident. CO poisoning accident is higher than any other gas accident in the rate of deaths/incidents. Most of these CO poisoning accidents were caused by defective exhaust tube in the old gas boiler and multi-use facility. In this study, the spread of CO gas released from leakage hole of exhaust tube was analyzed by computational flow modeling and concentration measuring test. CO gas leaked form exhaust tube in a building was highest concentrated near the ceiling and formed the circular currents along the walls. Through these experiments and simulation, the reasonable installation location of CO alarm was made certain and suggested.

• 한국기계가공학회지
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• 제12권1호
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• pp.28-34
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• 2013

For the senses of beauty and texture, internal components of small passenger cars are manufactured by texturing plastic with drawplate but those of deluxe passenger cars are manufactured by bonding pre-embossed skin to the surface of drawplate. As the pre-embossed skin is bonded at high temperature and pressure, the pattern of skin is distorted. The corner part is hardened and its dimension tolerance is changed by resulting in the increase with its defective rate. This study provides the method to design and manufacture the door trim track by vacuuming the non-patterned skin to upper-side drawplate which forms the pattern of descending skin. It is pressed to the plastic product with hot-press method and the damage of bossed-pattern is prevented. Valuation in this study has been done by analyzing, designing and experimenting method.

• 한국전기전자재료학회논문지
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• 제17권10호
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• pp.1114-1119
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• 2004

The photodepositioned tungsten film by laser CVD has been carried out the taping test with scotch tape over 10 times. As a result, it exhibited strong adhesion to the under-film such as ITO and SiNx patterned on the LCD substrate. However, it was seriously attacked by alkaline solution used for removing polyimide. And a thickness of laser CVD tungsten film had a close relation to a speed of laser scanning. Also we have improved the success rate of a laser CVD repair with making two pairs of contact hole structure and decreasing laser scanning speed.

• Animal cells and systems
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• 제12권3호
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• pp.127-136
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• 2008

Caspase-11 has been known as a dual regulator of cytokine maturation and apoptosis. Although the role of caspase-11 under pathological conditions has been well documented, its physiological role has not been studied much. In the present study, we investigated a possible physiological function of caspase-11 during immune response. In the absence of caspase-11, immunized spleen displayed increased cellularity and abnormal germinal center structure with disrupted microarchitecture. The rate of cell proliferation and apoptosis in the immunized spleen was not changed in the caspase-11-deficient mice. Furthermore, the caspase-11-deficient peritoneal macrophages showed normal phagocytotic activity. However, caspase-11-/-splenocytes and macrophages showed defective migrating capacity. The dysregulation of cell migration did not seem to be mediated by caspase-3, interleukin-$1{\alpha}$ or interleukin-$1{\beta}$ which acts downstream of caspase-11. These results suggest that a direct regulation of immune cell migration by caspase-11 is critical for the formation of germinal center microarchitecture during immune response. However, humoral immunity in the caspase-11-deficient mice was normal, suggesting the formation of germinal center structure is not essential for the affinity maturation of the antibodies.