Study on Aging Effect of Adhesion Strength Between Polyimide Film and Copper Layer

Seok‑Bon Koo,Chang‑Myeon Lee,Sang‑Jun Kwon,Jun‑Mi Jeon,Jin‑young Hur,Hong‑Kee Lee 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.1

This paper experimentally confirmed that the adhesion strength of the copper layer formed on the surface of the polyimidefilm by wet plating greatly changes with the aging time. The adhesion strength of the copper layer showed a rapid increasefrom 4 to 10 h after aging had begun and then converged to a value without a significant change. The adhesion enhancementbetween polyimide film and copper layer by aging is due to the interlocking effect caused by the volume expansion of copperoxide (CuO) formed in the polyimide, the increased mobility of copper particles enlarged by the decrease of impuritiesin the copper layer grain boundaries, and the consequent change of the crystal structure of the copper layer leading to theinternal stress reduction. Such adhesion improvement can be confirmed by the progress of the cohesive failure indicatingthe breakdown of the polyimide film.

면역학적 접근법을 이용한 미소대장암의 진단 및 외과적 치료

이기형,이석환,고석환 경희대학교 1997 慶熙醫學 Vol.13 No.1

요골 두 아탈구와 동반된 상완골 내 상과 골절 : 1예 보고 A Case Report

이한용,유기원,정진영,송주현,고해석,강용구,손문익 대한골절학회 2003 대한골절학회지 Vol.16 No.2

주관절 손산 중 상완골 내 상과 골절은 단독으로 혹은 주관절 탈구와 동반되어 발생하는 것이 일반적이다. 저자들은 15세 남자 환자의 좌측 요골 두 아탈구가 동반된 상완골 내 상과 골절을 경험하였다. 도수 정복을 시도하였으나 요골 두 아탈구의 정복을 얻을 수 없어 관혈적 정복술로 치료하엿다. 6개월추시 결과 후휴증이 없는 정상적인 관절 상태를 확인할 수 있었다. 연령, 원인 , 손상 기전으로 분석해 보면 이 동반 손상은 발생하기 매우 어렵고, 문헌 탐색 결과 현재까지 동일한 증례를 찾아볼 수 없었으므로 보고하는 바이다. It has been known that fracture of medial epicondylar apophysis of distal humerus may be isolated of associated with elbow deslocations. We have experienced a case which medial epicondylar fracture of the distal humerus was associated with subluxation of the radial head. Initially, we had tried reduction of subluxated radial head by closed method, but failed. Finally open reduction gad been performed. At 6 month after open reduction, clinical and radiological result were excellent. As it is difficult for those associated injuries to occur simultaneously and the similar cases never have been reported yet, we would like to present this case with a review of the literature.

모델 불확실성과 불확실한 잡음이 존재하는 시스템에 대한 LQG제어 시스템 설계

이기석,조택동 忠南大學校 産業技術硏究所 1994 산업기술연구논문집 Vol.9 No.1

The stability-robustness is one of the most important aspects to be considered in designing a control system. Because the mathematical model of a system is not perfect, there always exists modeling error. Therefore, model uncertainties should be investigated to design a stable control system. The Lyapunov's stability theorem, the singular value theorem, and the inequality of Cauchy-Schwarz are used to derive a constraint condition to guarantee the stability and the good performance of the real system. Although there exist model uncertainties and noises, the stability of the real system would be guaranteed if the constraint condition derived in this paper is satisfied. However, this constraint condition is not a necessary-sufficient condition but a sufficient one.

생쥐 대장 평활근 세포에서 내향 정류성 칼륨 전류의 특성 연구

이은주,김명,정명섭,조향훈,김기훈,하현철,김준수,최석,전제열 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Objectives: K^(+) channels play an important role in regulating cellular excitability. The aim of this study was to know whether or not inward rectifier K^(+) channel exists in colonic smooth muscle cells. Methods: Mouse colonic smooth muscle cells were isolated using collagenase, and then we recorded their membrane currents using a whole-cell patch clamp technique. Results: With 90 mM K^(+) in bath, hyperpolarization-induced inward currents from -120 mV to 20 mV with 400 ms duration at a holding potential of -10 mV showed rapid activation, inactivation and inward rectification. The inactivation showed single exponential time course. Reduction of external K^(+) to 60 mM decreased the amplitudes of the currents in whole test voltage range and shifted the reversal potential to more negative potential. The inactivation process and peak currents of hyperpolarization-induced inward currents were not affected by removing external Na^(+). External Ba^(+) blocked hyperpolarization-induced inward currents by dose-dependent manner and pure Ba^(+)-sensitive currents showed strong inward rectification. Cs^(+) also suppressed hyper- polarization-induced inward currents. Ba^(+) and Cs^(+)-induced inhibitiOn of hyperpolarization-induced inward currents was voltage-dependent, and the extent of inhibition increasing with membrane hyperpolarization. Conclusions: These results suggest that inward rectifier KU channels may exist in proximal colonic smooth muscle and may play an important role in regulating membrane potential.

치과용 임프란트의 박막코팅 표면처리

이기대,최석규 대구보건대학 2003 대구보건대학 論文集 Vol.23 No.-

This study was performed to examine the effect of electro-chemical treatment on the precipitation of apatite-like calcium phosphate in simulated body fluid. Titanium plates were polished from #600 to #2,000 sand paper and one surface of each specimen was received an additional polishing sequence through 0.1㎛ alumina paste. To improve the activity of titanium plates, they were electro-chemically treated at 100㎃ for 20min in an electrolyte containing the calcium and phosphate ions, and the temperature of electrolyte was held constantly in the range of 20∼80℃ during the treatment. All specimens were soaked in the (Hanks solution) with pH 7.4 at 36.5℃ for 30 days, and the surfaces were examined with XRD, SEM, XPS. Precipitation of calcium phosphate and CaO were observed on the electro-chemically treated titanium surface in a simulated body fluid after treatment at 600℃. Precipitation of calcium phosphate was densified and coarsened with increasing the temperature of the electrolyte solution in the range of 20∼80℃. The calcium phosphate contained phosphate in the form of PO₄^(3-), HPO₄^(2-) and H₂PO₄^(-1).

대장암 근치적 절제술후 재발양상에 관한 임상적 연구

이길연,홍성화,고석환,윤충,고영관,이기형,박주철 대한대장항문학회 1996 Annals of Coloproctolgy Vol.12 No.2

RS 및 GIS를 이용한 지형변화분석

김용인, 이승기, 조의환, 최석근 충북대학교 건설기술연구소 2009 충북대학교 건설기술연구소 논문집 Vol.28 No.2

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풍동시험에서 사용하는 시험지지부의 동특성 해석용 툴에 관한 연구

박태민,이기석,홍준희 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

This paper is described the program algorithm which can easily estimate dynamics of test support system by using mathematica tool based on the finite element method. We can determine the geometry, dimensions of the test support system, through tool stated in this paper for a certain test conditions. As a result of computer simulation and manufactured test support system's experiment in oder to verify suggested program, the dynamics of the test support system was well correspondent each other.

외상성 횡격막 손상

안성국,이상목,이기형,고석환,김용호,박호철,고영관,조규석 대한응급의학회 1995 대한응급의학회지 Vol.6 No.1

Fifty two cases of traumatic diaphragmatic injuries that we have experienced from Jan. 1973 to Oct. 1994 were evaluated. The following results were obtained. The age of the patient was ranged from 1 to 74 years. Male was 38 and female was 14 in number with a ratio of 2.7 : 1. The traumatic diaphragmatic injuries were due to blunt trauma in 35 cases(motor vehicle accident 25, fall down 8, press 1, kick by fight 1) and penetrating trauma in 17 cases(stab wound 15, shot wound 1, explosion 1). In the blunt trauma, the preoperative diagnosis of the diaphragmatic injury was possible in 25 out of 35 cases(71%) and in the penetrating trauma, 15 out of 17 cases(88%). In the blunt trauma, the repture site was located in the left in 22 cases(63%) and in the right in 13 cases(31%). In the penetrating trauma, the rupture site was located in the left in 9 cases(53%) and in the right in 8 cases(47%). In the blunt trauma, 20 cases(63%) were treated within 24 hours and in the penetrating, 15 cases(88%) within 24 hours. In the blunt trauma, the herniated organs into the thorax were stomach(7), omentum(6), spleen(6), liver(5), colon(4), small bowel(2) and in the penetrating, stomach(7), colon(6), omentum(3), liver(2), and spleen(1) were herniated. Injury severity score(ISS) of 35-blunt trauma ranged from 11 to 66 with mean value of 30.6. Mean ISS of survivors and nonsurvivors was 27.6 and 52.7 respectively. The diaphragmatic repair of 49 cases was performed with thoracic approach in 23 cases, thoracoabdominal approach in 7 cases and abdominal approach in 19 cases, and 3 cases were not operated. The postoperative complication and mortality were developed in 16 out of 49 cases(33%) and in 5 cases(9.6%) respectively, and the causes of death were hypovolemic shock(1), combined head injury(2), asphyxia(1), and pulomnary edema and renal failure(1). In conclusion, the injuries of the diaphragm should be suspected in all patients with severe blunt trauma or penetrating injuries at thorax and upper abdominal area near the diaphragm. All of the cases had associated injury and most of deaths were related to the severity of associated injuries.