후복막섬유증 5례의 임상적 고찰

정충식,김수현,안병수,심대성,박도영,김철성,장대수 조선대학교 1994 The Medical Journal of Chosun University Vol.19 No.1

Retroperitoneal fibrosis is a fibrotic process of the retroperitoneum that frequently produces ureteral obstruction. It can occur as an idiopathic disease or in association with various non-malignant and malignant condition. In the early phase of the retroperitoneal fibrosis ; symptoms originate from the disease process itself, while in the late state the clinical features represent the effect of obstructive uropathy and renal failure. Treatment consist of steroid therapy, urinary diversion and ureterolysis with jntraperitonealization or lateralization or wrapping with omentum. Herein we present 5 cases of retroperitoneal fibrosis.

응급환자에 대한 맥박산소측정기의 임상적 평가

안철민,이한식,조광현,황태식,김성규 대한응급의학회 1995 대한응급의학회지 Vol.6 No.2

Pulse oximetry is a noninvasive method of measuring blood oxygen saturation even before changes to the cardiopulmonary functions become apparent clinically. Therefore it has been widely excepted in many disciplines as a standard patient monitoring equipment. But its accuracy has been argued at low oxygen saturation levels. To determine the accuracy of the pulse oximetry in the emergency department where the patients presenting with respiratory difficulty are expected to have low oxygen saturation levels. Prospective, cross-sectional, paired measurements of oxygen saturation by two different pulse oxineters(SpO2) against oxygen saturation of arterial blood gas analysis(SaO2) was performed from May 1994 to September 1995 at two different university hospitals. Two pulse oxineters each with its digital probe were applied to the patient for the measurement of SpO2 simultaneously and arterial blood gas was drawn for analysis(ABGA) at the same time to measure SaO2. 98 patients who met the criteria mostly consisted of cardiopulmonary patients. There were no significant differences between mean SpO2(88.1±11.4, 88.2±10.0) of the two pulse oximeters and mean SaO2(88.7±11.4) from the arterial blood gas analysis(p=NS). Strong correlations were found(r=.80). But the regression declined as SaO2 decreased especially SaO2 < 90%. The pulse oximetry is potentially useful in patients with clinical signs of acute hypoxemia and patients receiving interventions that may produce acute hypoxemia, because of their ability to continuously monitor the oxygen saturation. But pulse oximetry along cannot identify the degree of hypoxemia or severity of distress. Therefore patients complaining of respiratory difficulty in an emergengy department, history and physical examination must be performed with pulse oximeter as a guide while backing it up with ABGA.

약골 골절후 발생된 골수염의 처치의 치험례

이철희,서정식,고말식,손동석,김성국 大韓顎顔面成形再建外科學會 1995 Maxillofacial Plastic Reconstructive Surgery Vol.17 No.3

With the use of antibiotics and improved dental care, osteomyelitis of the jaw is less common these days. But sometimes the management of osteomyelitis is more difficult because of appearance of resistant organisms to antibiotics. Treatment of the steomyelitis are incision and drainage, closed catheter irrigations, sequestrectomy, saucerization, hyperbaric ocygen therapy, and resection with or without bone graft. We experienced advanced osteomyelitis due to delayed treatment of left mandibular angle fracture. He have medical history of pschysoprenia. We decided to treat the patient with open reduction and closed cather irrigation. We achived reconsolidation of mandibular fracture accompanied by osteomyelitis by complete removal of inflammatory tissues, rigid fixation with miniplate and closed catheter irrigation.

골화석증(Osteopetrosis) 증례보고

성철수,강창수,편영식 啓明大學校 醫科大學 1986 계명의대학술지 Vol.5 No.2

Osteopetrosis (also called Albers-Schonberg's disease, marble bones and chalk bones) is rare developmental abnormality in whiiich, on the basis of a failure of osteclastic and chondroclastic resorption, the bone become exceedingly dense. Two clinically distinct forms are now recognized and have different patterns of inheritance. The milder form is transmitted as an autosomal dominant trait and the more severs form is tranmitted as an autosoamal recessive trait. Symptoms and complications are caused by insufficient development of the bone marrow and by bony encroachent on the cranial formina. We report a case of milder form of ostepetrosis with a review of literature.

드레인 전류 잡음원만을 고려한 스케일링이 가능한 바이어스 의존 P-HEMT 잡음모델

윤경식,이창석,맹성재,이진희,박철순 대전산업대학교 반도체기술연구소 1999 半導體技術硏究所報 Vol.1 No.-

게이트 길이가 0.2㎛인 P-HEMT에 대하여 드레인 바이어스 전류의 변화 및 게이트 폭에 대해 스케일링이 가능한 잡음모델을 제안하였다. 본 논문에서는 S-파라미터를 정확히 예측하기 위하여 x를 제외한 intrinsic 파라미터는 offset를 도입하여 정규화 한 후 스케일링을 하였다. 드레인 포화전류에 대한 드레인 전류의 비율과 게이트 폭을 변수로 하는 소신호 모델 파라미터의 맞춤함수를 구하였다. 또한, 잡음 파라미터를 정확히 예측하기 위하여 진성저항 잡음 온도 T_g, 게이트 단 전류 잡음원 등가잡음 컨덕턴스 G_ni 드레인 단 전류 잡음원 등가잡음 컨덕턴스 G_no를 잡음 모델정수로 사용하여 그 값을 추출하여 스케일링 하였다. 잡음 온도 T_g는 드레인 전류와 게이트 폭에 거의 추출되었다. 그러므로, G_no만을 잡음 모델정수로 하는 잡음모델과 T_g, G_ni, G_no를 잡음 모델정수로 하는 잡음모델을 측정값과 비교하여 본 결과 G_no만을 갖는 잡음모델도 측정된 잡음 파라미터와 잘 일치하였다. 따라서, 모델 정수 추출이 간단한 G_no 만을 갖는 잡음모델은 게이트 폭과 바이어스 전류에 대해 스케일링이 가능한 실용적인 잡음모델임을 확인하였다. Bias-dependent noise models of 0.2㎛ gate length P-HEMT's which are scalable with gate width are proposed. To predict S-parameters of the P-HEMT's the intrinsic parameters except for x subtracted the offsets introduced in this paper are normalized to the gate width and then scaled. The small-signal model parameters are expressed as fitting functions of the drain current to I_dss ratio and gate width. In addition, to estimate accurately noise parameters the noise temperature T_g of the intrinsic resistance, the equivalent noise conductance G_ni of the gate current noise source, and the equivalent noise conductance G_no of the drain current noise source are adopted as the noise model parameters. The extracted values of T_g are nearly independent of drain current and gate width and their average is arou

造船用 資材管理 system 開發을 위한 資材 CODE 開發

이철식,황규옥 충남대학교 경상대학부설 경영경제연구소 1991 경영논집 Vol.7 No.2

SM45C의 Laser 표면개질 조건에 따른 마멸특성에 관한 연구

옥철호,임동욱,서영백,박흥식,전태옥 동아대학교 생산기술연구소 2000 生産技術硏究所硏究論文集 Vol.5 No.1

Surface modification of plain carbon steel (SM45C) by Laser are usually much finer and stronger than the base metals. Nd-YAG laser source changes and refines the microstructure of the near surface layer, leading to enhanced hardness and wear resistance. The present study was undertaken to investigate the wear behavior and a processing parameters such as, power density, pulse width, defocusing distance, and molten depth for surface modification. The wear test was carried out under different experimental condition using the wear test device and the annular surfaces of wear test specimens as well as mating specimen of alumina ceramics(Al_2O_3) was rubbed in dry sliding condition. The results show that molten depth and width depend on defocusing distance. The wear loss was much in lower speed range below 0.2m/sec and in higher speed range above 0.7m/sec, but It was little in intermediate speed range. It depends on oxidation and wear speed.

연합고사에 의한 고교 신입생 배정방법에 관한 연구 : 특히 선지원·후시험 배정제도를 중심으로

이철식,홍순태 충남대학교 경상대학부설 경영경제연구소 1990 경영논집 Vol.6 No.1

非晶質 Silicon 薄膜의 製作 및 그 Doping 效果

최범식,김수길,고년규,황정남,정원모,이철주 연세대학교 자연과학연구소 1982 學術論文集 Vol.9 No.-

SiH_4 기체에 PH_3 및 B_2H_6 기체를 0.7% 체적비로 혼합하여 rf glow 방전법으로 n형 및 p형 a-Si:H 박막을 기판온도 120℃에서 제작하여, 광투과도 측정, 열처리에 따른 전기 전도도의 변화 등을 조사하여 이들의 doping 효과를 연구하였다. n형, p형 및 undoped a-Si:H 박막의 optical gap은 각각 1.73eV, 1.86eV 및 1.86eV로 doping이 많이 이루어질수록 줄어 들었다. 250℃에서 열처리한 시료들의 상온에서의 전도도는 각각 2×10^-2Ω^-1㎝^-1, 5×10^-8Ω^-1㎝^-1, 5×10^-7Ω^-1㎝^-1이었고, 활성화 에너지 ??E는 각각 0.16eV, 0.49eV 및 0.48eV이었다. 300℃에서 열처리한 결과, ??E는 줄어 들고 전도도는 증가하였다. 350℃ 및 450℃에서 열처리한 결과 dehydrogenation 효과로 인하여 n형과 p형은 서로 상반되는 결과를 보였다. 즉, n형 시료의 전도도는 감소하고 ??E는 증가하였지만, P형 시료의 전도도는 증가하고 ??E는 감소하였다. 저온 영역에서 구한 n형 시료의 전도도로부터 hopping 활성화 에너지를 구한 결과 0.085eV이었다. Thin n-type and p-type a-Si:H films were prepared by rf glow discharge decomposition of silane mixed with 7×10^-3 parts per volume of phospine or diborane. All specimens were deposited on glass substrates held at 120℃. In order to determine the doping effects the opital absorption and dc conductivity of these specimens were measured after annealing at various temperatures. The optical gap was 1.73eV in the case of the n-type specimens, 1.80eV for the p-type, and 1.86eV undoped. This showed that the gap width decreased as the doping increased. The room temperatuer conductivities of these specimens annealed at 250℃ were 2×10^-2Ω^-1㎝^-1, 5×10^-8Ω^-1㎝^-1, and 5×10^-7Ω^-1㎝^-1, respectively, and the activation energies, ??E, of these specimens were 0.16eV, 0.49eV, and 0.48eV, respectively. For specimens annealed at 300℃, ??E decreased and the conductivity increased. When these specimens were annealed at 350℃ and 450℃, dehydrogenation caused opposite effects on the n-type and p-type specimens; the conductivities of n-type specimens decreased and ??E increased, but the conductivities of p-type specimens increased and ??E decreased.From an investigation of the temperature dependence of the conductivity of the n-type specimen in the low temperature region, we determined that the hopping activation energy was 0.085eV.

PERT/CPM의 效果的 實行·統制를 위한 融通性있는 프로젝트 日程計劃시스템(FPSS)에 관한 硏究

李徹植,李判權 충남대학교 경상대학부설 경영경제연구소 1993 경영논집 Vol.9 No.1