병원간접원가의 예측수단으로서의 회귀식 모형과 인공신경망 모형에 대한 비교연구

양동현,박광훈,김선민 한국병원경영학회 1999 병원경영학회지 Vol.4 No.2

This research aims to compare between regression and neural network in terms of the predictive ability of the overhead costs in hospitals. For this purpose, this research uses the number of out-patients and complex medical treatments as explaining variables. Thirty-one hospitals were used for the empirical test. The test result shows that the regression model has a more predictive ability than the neural network.

단감 저장병 원인균 검은 곰팡이 분리 보고

안광환,배영민,김동완,주우홍 Institute of Genetic Engineering Changwon National 2002 Gene and Protein Vol.6 No.-

To develop the biological control agents on postharvest diseases of persimmon fruits, several fungi were isolated from decayed persimmons after several months in cold storage. One major pathogen of postharvest disease was identified on the basis of morphological characteristics as Aternaria sp..

당뇨병성 합병증을 가진 환자에서 혈중 Erythropoietin 농도

김동규,유기동,허광식,김상용,윤성호,조영신,권용은,김태원,김건영,정종훈,배학연 朝鮮大學校 附設 醫學硏究所 1998 The Medical Journal of Chosun University Vol.23 No.1

연구 배경 : 고혈당성에 의한 산화환원반응 이상(가저산소증)이 조절 되지않는 당뇨병의 특징으로 혈관과 신경 기능에 대한 진성 저산소증의 효과와 유사하며, 당뇨 합병증의 병태생리에 중요한 역할을 한다. 고혈당이 있는 인슐린 비의존형 당뇨병 환자에서 인슐린 수준이 정상이듯이, 빈혈이 있는 당뇨병 환자에서 EPO의 농도는 실제 혈색소 농도의 감소비율과 차이가 있을 것이라 추측된다. Friedman 등은 당뇨병성 합병증 원인 인자로 가저산소증(pseudohypoxia) 또는 저산소증(hypoxia)을 제기하였고 이런 인자들이 EPO의 상대적 또는 절대적 결핍에 의한 것임을 보고하였다. 방법 : EPO-Trac^(TM 125)I RIA kit을 이용하여 방사면역측정법으로 EPO 수준을 검사하였다. 전혈 3㎖을 5-10㎖ 시험관에 정맥 채혈하였으며, 용혈과 장기간의 보존을 위하여 원심분리를 즉시 시행하여 혈청을 영하 200C에서 냉동 보관 후 일괄적으로 검사 결과를 얻었다. 결과 : 1996년 9월부터 1997년 2월까지 조선대학교 부속병원 내과에 입원한 2형 당뇨병 환자 63례를 대상으로 하여 다음과 같은 결과를 얻었다. 1) 당뇨병성 합병증이 없는 군과 있는 군간의 혈색소, 혈중 EPO농도의 차이는 유의한 차이가 있었으며 혈색소의 감소율보다 혈중 EPO의 감소율이 더 높았다. 2) 당뇨병성 망막증의 유무에 따른 혈색소 농도의 차이는 유의한 차이가 없었으나 혈중 EPO농도는 유의한 차이가 있었다. 증식성군에서만 혈중 EPO의 감소비율이 혈색소에 비해 높았다. 3) 당뇨병성 신증의 유무에 따른 혈색소, 혈중 EPO농도는 유의한 차이가 있었고 혈색소 감소율에 비해 EPO농도의 감소율이 높았다. 신증의 중증도에 따른 혈색소, EPO의 차이는 미세알부민뇨군을 제외하고는 유의한 차이를 보였고 혈색소 감소율에 비해 EPO의 감소율이 더높았다. 4) 당뇨병성 신경병증의 유무에 따른 혈색소 농도의 차이는 유의한 차이가 없었으며 EPO농도는 유의한 차이를 보였다. 혈색소와 EPO의 감소비율은 비슷하였다. 신경병증의 중등도에 따른 혈색소와 EPO농도의 변화는 유의한 차이가 없었으나 stage 3에서는 혈색소감소율보다 EPO감소율이 더높았다. 결론 : 당뇨병성 합병증을 가진 환자에서 빈혈의 정도는 대부분 혈청 EPO치의 절대적 감소에 의함을 간접적으로 밝혀낼 수 있었으며 차후 더 많은 대상으로 비교 분석이 필요하리라 사료된다. Background: Hyperglycemic-induced redox(pseudohypoxia) imbalance is a characteristic feature of poorly controlled diabetes that mimics the effects of true hypoxia on vascular and neural functions and plays an important role on the pathogenesis of diabetic complications. As is true for apparently "normal" insulin levels typically found in NIDDM even in the presence of hyperglycemia, a "normal" erythropoietin level in an anemic diabetic subject may be disproportionally low for the actual red cell mass. Therefore, Friedman et al suggested that pseudohypoxia or hypoxia as an etiological factor of diabetic complications are due to absolute or relative erythropoietin deficiency Method: EPO-TracTM 125I RIA kit was used for the quantitative determination of erythropoietin(EPO) in serum by radioimmunoassay. An adequate sample of blood (3ml whole blood) was collected aseptically by venipuncture in a 5~10ml glass tube to yield a minimum of 400 L of serum per assay. The serum was promptly removed from the clot by centrifugation in order to avoid hemolysis. Then to increase its storage time it was frozen at -200C in a nonself defrosting freezer. Finally, tests were undertaken simultaneously Results We studied 63 cases with diabetes mellitus, who were admitted to Chosun University Hospital from September, 1996 to February, 1997 at the Department of Internal Medicine. We defined the control group, as diabetic patients who did not have anemia(<13mg/dl), diabetic complications(retinopathy, nephropathy, neuropathy) and the remainders were defined as the experimental group(we excluded anemic patients, who had secondary causes of anemia and diabetic patients with end stage renal disease)Data were as follow 1) The relationship of Hb and the 24hr urine protein between diabetic patients with and without complications significantly differed(p=0.02, < 0.001 respectively), but the Hb level was poorly related between diabetic patients with and without retinopathy(except in preproliferative, proliferative subgroups) and neuropathy. 2) Subgroups of patients with diabetic complications had higher 24hr urine protein than patients without diabetic complications, except stage I diabetic neuropathy 3) The EPO level was significantly different between diabetic patients with and without complications. 4) The correlation between EPO and Hb was significantly different, especially in diabetic patients with retinopathy and nephropathy according to severity of diabetic complications, compared with patients who did not have diabetic complications such as retinopathy and nephropathy. Conclusion: We know that anemia induced by diabetic complications is due to relative EPO deficiency than absolute EPO deficiency, and further evaluation and studies are needed on many cases in the future

혈우병 환자에 동반된 자발성 후복막강 출혈

김광일,김동호,우상민,이석주,김홍성,조인성,윤환중,조덕연,김삼용 충남대학교 의과대학 지역사회의학연구소 1997 충남의대잡지 Vol.24 No.1

Spontaneous retroperitoneal hemorrhage due to hemophilia A with impaired coagulopathy is very rare. Spontaneous retroperitoneal hemorrhage has been recorded as having originated from many retroperitoneal organs and blood vessels, and it may be due to local and/or systemic factors. In the majority of the patients, kidney and adrenal gland were the major site of hemorrhage. The systemic causes of spontaneous retroperitoneal hemorrhage are anticoagulation therapy and chronic hemodialysis. During the course of these treatments, hemorrhagic complications may occur at many site, including the retroperitoneal space. Blood dyscrasias including leukemia, polycythemia, sickle cell trait and hemophilia have been reported associated with spontaneous retroperitoneal hemorrhage. We report a case of spontaneous retroperitoneal hemorrhage occurred in a gemophilia A patient with brief review of literature

수술 전 진단된 충수돌기 점액류종 1례

허광식,손현화,김동규,박찬국,김만우,김정용,기근홍 조선대학교 부설 의학연구소 2000 The Medical Journal of Chosun University Vol.25 No.1

Primary unruptured appendiceal mucocele is a rare disease. It is very difficult to diagnose preoperatively because of the rarity of classical symptoms and low incidence. Usually it is discovered incidentally during abdominal ultrasonography(US), computed tomography(CT), or appendectomy for acute appendicitis. If untreated, one type of mucoceles may rupture producing a potentially fatal entity known as pseudomyxoma peritonei, therefore preoperative diagnosis is very important. With the advent of colonoscopy, abdominal US and CT, it has been possible to preoperatively diagnose mucocele of appendix. We experienced a case of appendiceal mucocele in a 60 year-old woman who had symptoms of lower abdominal discomfort and right lower quadrant abdominal pain, and it was diagnosed preoperatively by colonoscopy, abdominal US and CT. So we present this case with review of literature.

감마선투과검사 장치의 자동 원격조작기 개발

주광태,신진성,김동언,송정호,주승환,장홍근 한국비파괴검사학회 2002 한국비파괴검사학회지 Vol.22 No.5

국내 감마선투과검사용 조사장치는 1,000여대로 2,500여명의 종사자가 대부분 수동으로 원격 조작하는 실정으로 작업의 효율화와 방사선피폭 저감화를 위하여 자동 원격조작기의 사용이 요구된다. 이에 연구팀은 실무에 적합한 토크와 안전계수로부터 54kgf·㎝의 출력을 지닌 24V, 200W의 BLDC모터를 이용하여 0.4∼1.2 m/s 범위의 선원 이동속도를 조절할 수 있는 구동장치와 RF 센서로 구동 속도 조절, 광전센서에 의한 선원 위치 및 timer로 노출시간을 제어할 수 있는 무선 원격조작기를 개발하였다. 이와 같이 개발한 자동원격조작기는 AC와 DC 겸용, 그리고 기존의 수동 원격조작기에 탈착이 가능하여 자동과 수동을 겸용할 수 있는 경제적 이점 등으로 활용도가 클 것으로 기대된다. Recently, gamma radiographic equipments have been used about 1,000 sets manually and operated by about 2,500 persons in Korea. In order for a radiography to work effectively with avoiding any hazard of the high level radiation from the source, many field workers have expected developing a wireless automatic remote exposure controller. The KITCO research team has developed an automatic remote exposure controller that can regulate the speed of 0.4∼1.2 m/s by BLDC motor of 24V 200W which has output of 54 kgf·㎝, suitable torque and safety factor for the work. And the developed automatic remote exposure controller can control rpm of motor, pigtail position by photo-sensor and exposure time by timer to RF sensor. Thus, the developed equipment is expected that the unit can be used in many practical applications with benefits in economical advantage to combine the use of both automatic and manual type because attachment is possible existent manual remote exposure controller, AC and DC combined use.

인장하중을 받는 의사등방성 복합재 적층판의 피로손상

양광영,임경택,이동하,김택현,김인권 朝鮮大學校 機械技術硏究所 1999 機械技術硏究 Vol.2 No.1

The purpose of this work is to investigate fatigue damage of quasi-isotropic laminates under tensile loading in different directions. Low cycle fatigue tests of [O/-60/+60]s laminates and [+30/-30/90]s laminates were carried out. Materials systems used are AS4/Epoxy and AS4/PEEK. The fatigue damage of [+30/-30/90]s is very different from that of [O/-60/+60]s. The position of delamination generated at AS4/Epoxy and AS4/PEEK laminates were differentiated by the matrix difference that is, we suppose, the value of both G (critical energy release rate of mode-I) and G (critical energy release rate of mode-Ⅲ) difference. The experimental results are compared with the result obtained from the method of determining strain energy release rate components proposed by the authors.

단감 저장병 원인균 푸른 곰팡이 분리 보고

안광환,배영민,김동완,주우홍 Institute of Genetic Engineering Changwon National 2002 Gene and Protein Vol.6 No.-

To develop the control method of postharvest disease on persimmons, the analysis of a major pathogen of postharvest disease and incidence of the disease on persimmon fruits were studied from 2001 to 2002. A major postharvest pathogen was identified on the basis of morpholoical characteristics as Peniacillium sp..

재순환 버퍼 RLS 알고리즘의 탭 가중치 갱신을 통한 개선된 수렴 특성

김광준,윤찬호,윤민종,나상동 조선대학교 에너지.자원신기술연구소 1999 에너지·자원신기술연구소 논문지 Vol.21 No.2

We extend the sue of the method of least square to develop a recursive algorithm for the design of adaptive transversal filters such that, given the least-square estimate of this vector of the filter at iteration n-1, we may compute the updated estimate of this vector at iteration n upon the arrival of new data. The RLS algorithm may be viewed as a special case of the Kalman filter. Indeed this special relationship between the RLS algorithm and the Kalman filter is considered. We begin the development of the RLS algorithm by reviewing some basic relations that pertain to the method of least squares. Then, by exploiting a relation in matrix algebra known as the matrix inversion lemma, we develop the RLS algorithm. An important feature of the RLS algorithm is that it utilizes information contained in the input data, extending back to the instant of time when the algorithm is initiated. The resulting rate of convergence is therefore typically an order of magnitude faster than the simple LMS algorithm. This improvement in performance, however, is achieved at the expensive of a large increase in computational complexity

이원화, 다계화, 네트워크 구축전략 : 일본의 대아시아 직접투자전략

조동성,이광현,이윤철,김태현 韓國國際經營學會 1995 國際經營硏究 Vol.6 No.1

본 연구는 1985년 이후 엔고와 더불어 급증한 일본의 대아시아 직접투자를 기업전략적인 차원에서「이원화전략」,「다계화전략」,「네트워크 구축전략」의 관점에서 설명하고자 한다. 여기서 이원화 전략이란 기술전파를 막기 위해 첨단기술을 요하는 고부가가치 제품은 국내에서 생산하고, 노출가능한 기술을 사용하여 생산하는 중저가 제품은 해외에서 생산함으로써 후발개도국들의 추격을 따돌리는 전략을 의미한다. 한편 다계화전략이란 투자국의 경제 발전에 따라 일본기업의 생산입지를 단계적으로 변화시키는 전략이다. 마지막으로 네트워크를 구축전략이란 일본기업이 아시아 투자가 개별적으로 이루어 지지 않고, 총체적인 경쟁우위를 향상시키기 위해 기존 해외 네트워크의 연장선 하에서 이루어진다는 것이다. 이러한 일본기업의 아시아 해외투자전략에 대응해서 전통적으로 일본으로부터 기술을 수입해 온 한국기업이 일본기업을 추격하기 위해서는「전문화전략」,「투자지역 선도전략」및「보완적 네트워크 구축전략」을 채택해야 할 것이다. 한편 한국과 같은 선발개도국을 모델로 하여 경제개발을 추구하고 있는 다른 아시아국가들 역시 본 논문을 통해 일본기업들의 전략적 의도를 파악하고, 이에 대응하기 위해「자체능력 개발전략」및「네트워크 연결전략」을 채택할 필요가 있다.