CT법을 이용한 진직도 및 직각도 측정에 관한 연구

이승수,김민주,박정보,전언찬 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.1

As high-precision parts are needed with manufacturing techniques improved, the demand of high-precision machine tools has been increasing. They are made to developed the precision measuring skill to maintenance the accuracy of themselves as a matte of course. We on the paper measured straightness and orthogonality of the square to verify that is possible for CT(circular test) method by 2-dimensional probe and the square to measure orthogonality. Furthermore, we compared the result of the study with the computer simulation's to prove its possibility, and made an improvement of measuring method.

기관지천식 환자에서 유도객담을 이용한 기도 염증의 평가

남언정,이종명,김건우,김신우,김능수 경북대학교 병원 2003 경북대학교병원의학연구소논문집 Vol.7 No.1

Objectives : This study was performed to investigate the relationship between cell counts, supernatant and lysate ECP levels in sputum, and physiologic markers in adult asthmatic. Methods : Twenty-two patients with mild to moderate persistent asthma, ten patients with acute exacerbated asthma and nine healthy subjects were enrolled. Sputum was induced by inhalation of hypertonic saline, and homogenized with 0.1% dithiothreitol. A total and differential cell was measured in supernatant fluid. Cell pellet was centrifuged, and ECP(supernatant ECP) was measured in supernatant fluid. Cell pellet was reacted with a cellular lysis buffer to release cell-associated ECP, and ECP(lysate ECP) was measured again in supernatant fluid. The ratio of supernatant to lysate ECP was calculated as an index of eosinophil degranulation. Spirometry and methacholine bronchial challenge tests were also performed as physiological markers of asthma. Results : The patients with acute exacerbated asthma showed significantly higher percentage of sputum neutrophil, eosinophil count, concentration of sputum supernatant ECP and ratio of supernatant to lysate ECP than those of normal controls and stable asthmatic patients(p<0.05, respectively). The level of sputum supernatant ECP, supernatant/lysate ECP ratio, and percentage of neutrophil showed negative correlations with pulmonary functions, but no correlations with a degree of bronchial hyperresponsiveness. There was no significant correlations between of serum ECP level and physiological parameters. Conclusion : These results suggest that both neutrophils and eosinophils play roles in the exacerbation of asthma. The sputum supernatant/lysate ECP ratio might be valuable in assessment of activation status of eosinophils in various hypereosinophilic conditions or diseases.

담석 환자에서 65세 이상과 미만 환자군의 비교

문언수,이태의 대한노인병학회 2000 Annals of geriatric medicine and research Vol.4 No.4

호닝 가공에 사용되는 다이아몬드 공구의 성능평가에 관한 연구

김민주,이승수,전언찬 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.1

This study is to evaluate the tool performance in honing using diamond reamer and present grounds whether the localized products are sufficiently competitive comparing with the existing imported ones. The heads of the tool performance evaluation are roundness, roughness, tool life of the workpiece and so on. When evaluating the tool performance, cutting process is divided by three areas which are rough, semi-finish and finish cut. Honing improves the accuracy such as boring and reaming after manufacturing the inside diameter, and finishing directly by boning is a recent trend. This honing is used greatly in hard cutting materials like cemented carbides and it is the CBN and diamond that is used in hard cutting materials. Both of them are expensive and most of them are imported.

자동차용 냉연강판의 풀림방법이 성형성에 미치는 영향

김순경,이승수,전언찬 동아대학교 공과대학부설 생산기술연구소 1998 生産技術硏究所硏究論文集 Vol.3 No.1

The formability of an automobile body panel is very important. So, we performed an annealing condition change for the development of annealing condition with temperature, atmospheric gas and the annealing cycle. Formability was changed under the influenced of the mechanical properties of steel sheet for the automobile body panel. Thwerfore, it is important in the BAF(Batch annealing furnace) annealing process. Because mechanical properties were decided on the heat treatment method of the coil. So, we tested the development of mechanical properties according to the heat treatment method at the annealingfurnace using the Ax atmospheric gas and the HNx atmospheric gas. As a result of several investigations, we confirmed the following characteristics ; mechanical properties change under the influence of the annealing cycle and atmospheric gas.

BTA드릴에 의한 심공가공시 최적절삭조건과 공구수명에 관한 연구

장성규,이충일,전언찬,안찬우,김현수 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.2

The BTA deep hole machining has an increasing because of its wide range applications and its good productivity. The BTA tools are capable fo machining for having a large length to diameter ratio in single pass. It's really necessary that the research for machining of the deep hole drilling by the BTA drilling because its required quality should be satisfied with one time machining. In machining deep holes by single edge BTA drill, P10 class of tool material out of single tube BTA drilling system, we got the result of our study of selecting the optimum cutting condition and tool life for an object, SM55C through our testing as follows. (1) Cutting speed V=42m/min, and feed speed F=90mm/min is the optimum cutting condition and the tool life was about 10 meters. (2) The testing was shown surface roughness was 12㎛, and the roundness was less 16㎛.

자동차용 강판의 열처리 특성에 관한 연구

김순경,이승수,전언찬 동아대학교 공과대학부설 생산기술연구소 1998 生産技術硏究所硏究論文集 Vol.3 No.1

Development on the mechanical properties of steel for the automobile body panel is very important in the BAF(Batch annealing furnace) annealing process. Because of the heat treatment in method the BAF, mechanical properties was decides on the heat treatment method of the coil. So, we tested on the development of mechanical properties according to heat treatment method at the annealing furnace using the Ax atmospheric gas and the HNx atmospheric gas. As a result of several investigations. We confirmed the following characteristics ; mechanical properties was changed under the influence of the annealing cycle and the atmospheric gas. The coil spot of coil was the mid point of the B coil in the Ax atmospheric gas. And, atmospheric gas is very important in the high convection annealing furnaces.

BAF Annealing에서 저온점의 온도변화에 관한 연구

김순경,이승수,김문경,전언찬 동아대학교 공과대학부설 생산기술연구소 1997 生産技術硏究所硏究論文集 Vol.2 No.2

As demand for various kinds and small lot products has been increasing, batch annealing has been appreciated for its small restriction for the operation. The cold spot of the coil is very inportant in the BAF(Batch annealing furnace) annealing process. Because of the annealing cycle time in the BAF, annealing was decided on the cold spot of the coil. So, we tested the effect, variation of cold spot, for hydrogen contents of atmospheric gas at the annealing furnace. As a result of several investigations. We confirmed the following characteristics ; after the heating and soaking, the cold spot of coil moved to 1/3 of coil thickness in the HNx atmospheric gas, but the mid point of the coil thickness is the cold spot in the Ax or H₂atmospheric gas. Therefore, the use of hydrogen instead of nitrogen as the protective gas, combined with high convection in batch annealing furnaces, has shown that considerable increases in furnace output and material quality are attainable. Owing to the low density, high diffusion and reducing character of hydrogen, a better transfer resulting in uniform material temperatures and improved coil surfaces can be achieved.

분위기 가스가 냉연강판의 성형성에 미치는 영향

김순경,이승수,전언찬 동아대학교 공과대학부설 생산기술연구소 1998 生産技術硏究所硏究論文集 Vol.3 No.1

Development on the mechanical properties of steel for the automobile body panel is very important in the BAF(Batch annealing furnace) annealing process. Because of the heat treatment in the BAF, mechanical properties was decided on the heat treatment method of the coil. So, we tested on the development of mechanical properties according to heat treatment method at the annealing furnace using the Ax atmospheric gas and the HNx atmospheric gas. As a result of several investigation. We confirmed the following characteristics ; mechanical properties was changed under the influence of the annealing cycle and the atmospheric gas. And, We have some result according to heat treatment method. 1. elongation one of the mechanical properties was good NHx BAF than Ax BAF. 2. The cost of heat treatment was expensive HNx BAF than Ax BAF. We will arrange a annealing cycle in order to gain a good quality of CQ and DDQ Sheet. Because Even if we save a cast, mechanical properties were no better.

저탄소강의 풀림 사이클에 대한 예측 프로그램 개발

김순경,이승수,김문경,전언찬 동아대학교 공과대학부설 생산기술연구소 1997 生産技術硏究所硏究論文集 Vol.2 No.2

The cold spot of the coil is very important in the BAF(Batch annealing furnace) annealing process. Because of the annealing cycle time in the BAF, annealing was decided on the cold spot of the coil. So, we tested the temperature variation of cold spot and the correctness of computer simulation at the annealing furnace using the Ax atmospheric gas. As a result of several investigations. We confirmed the following characteristics ; Annealing cycle was changed under the influence of the strip surface condition and the strip tension. The cold spot of coil was the mid point of the B coil in the Ax atmospheric gas. And, the power of recirculation fan is very important in the high convection annealing furnaces.