Paste법에 의한 0.1V강의 침붕처리에 관한 연구

권동일,김강형,김진관,이성훈,윤재홍 國立 昌原大學校 産業技術硏究所 1994 産技硏論文集 Vol.8 No.-

0.1V강의 표면경도를 향상시키기 위해서 Boronizing처리를 실시하여 Hv=1500∼2000의 높은 경도값을 나타내는 붕화물층을 얻었다. 붕화물층의 두께와 처리시간과의 사이에는 방물선관계를 나타내었으며 붕화물층 생성 겉보기 활성화에너지는 94kJ/mol이다. 또한 900˚C, 3시간 침붕처리했을 때가 가장 높은 경도분포값을 나타내었으며 그 이상 장시간 처리하면 오히려 경도가 감소하는 경향을 나타낸다. 그리고 침붕층은 20% HCl, 20% H₂SO₄용액에서는 뛰어난 내식성을 가지나, 20% HNO₃용액에 대해서는 상대적으로 내식성이 떨어졌다. 그리고 내고온산화성은 대기중 800˚C까지는 침붕처리한 시편이 우수했으나 900˚C부터는 오히려 감소했다. To improve the surface hardness of the 0.1V steel, by Boronizing Treatment, We got boride layer showing high hardness, Hv=1500∼2000. A parabola relationship was appeared between boride layer thickness and treatment time, and apparent activation energy to form the boride layer 94kJ/mol. Moreover, We obtained the most high hardness distribution value when had the boronizing treatment for 3 hours at 900˚C. On the contrary, If we did boronizing treatment above 3 hours, the hardness appeared decreasing tendency. The boride layer had a good corrosion resistance at a solution of 20% HCl and 20% H₂SO₄, but correlatively the corrosion resistance of the boride layer was declined at a solution of 20% HNO₃. And the boronized specimen had a good high temperature oxidation resistance until 800˚C in the atmosphere but the high temperature oxidation resistance go down above 900˚C.

치성낭종으로부터 유래된 편평상피세포암종 : Report of a Case & Review of Literatures

권혁진,현재훈,박형국,김용각 大韓顎顔面成形再建外科學會 1997 Maxillofacial Plastic Reconstructive Surgery Vol.19 No.2

Odontogenic cysts are relatively common pathologic lesions found in the oral and perioral structures, but the case of squamous cell carcinoma arising from those cysts are very uncommon. After first reported of that case in 1889 by Herman, Schwimmer collected 56 cases of previously reported squamous cell carcinoma arising in residual odontogenic cyst during about past one century. More than 60% of cases of carcinoma developing in odontogenic cysts arising in inflammatory periapical or residual cyst, and these tumors are usually well-differentiated with relatively good prognosis, and often are diagnosed as benign lesion in radiographic or clinical examination, therefore definitive diagnosis must be made by histologic examintation. We report a case and review the literatures, in our case, 78-year old woman were clinically and radiographically diagnosed as residual odontogenic cyst. But in histologic examination after enucleation of lesion, mass of squamous cell carinoma were observed, but in other area, typical cyst wall and lining epithelium were observed. And in some area, carcinoma in situ and invading squamous cell carcinoma into the lining epithlium were also observed.

기관내 삽관 후 발생한 기관 괴사와 협착증 : 증례보고 A case report

권진형,구자욱,유시현 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

Tracheal necrosis and stenosis are rare complications of prolonged endotracheal intubation. A 62 years old female was performed cerebral aneurysmal neck clipping under general anesthesia via endotracheal intubation and transferred to the 12th intensive care unit. The patient was mechanically ventilated and tracheostomy was done on the postoperative day. Necrotic tissue, pus and stenosis were found around the ballooning site of the trachea. T-tube insertion was done on the both postoperative day and the patient was discharged on the 80th postoperative day.

유아의 기관절개술에서 발관방지를 위해 고안된 기관절개 튜브

권진형,김성운,오천환 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

Tracheostomy in infants and children is associated with a high rate of accidental decannulation in the early postoperative period. The most common complication in infants and children, which most often results in death, is accidental decannulation. Other authors advocate suturing tracheostomy tubes in place in infants and children under general anesthesia in operating room for avoiding decannulation. The authors designed tracheostomy tube for the prevention of accidental decannulation following tracheostomy in infant, so report with review of literatures.

중복 자궁 경부, 맹낭성 종질중격 및 동측 신장발생부전을 가진 교통성 중복자궁 1례

김윤진,전명권,이응수,최형민 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.4

The class of uterine malformation known as communicating uteri is characterized by two uterocervical cavities connected by an isthmic communication. We experienced case of communicating double uterus with double cervix, blind hemivagina and ipsilateral renal agenesis. The complaint of the patient was odorous vaginal discharge with lower abdominal pain unrelated with menstrual cycle. We confirmed these Mullerian anomalies by transvaginal ultrasound. IVP(intravenous pyelography), MRI(magnetic resonance imaging), hysterosalpingography and hysteroscopy. After vaginal septoplasty, her complaint was subsided. We report this case with brief review of literatures.

Effects of Oxygen Pressure on the Crystalline of ZnO Films by PLD Method

조재형,허태봉,곽진성,권대영 부산대학교 유전체물성연구소 2005 유전체 논문집 Vol.4 No.

We studied the effects of oxygen pressure on the ctystalline of ZnO films on sapphire(001) substrates were deposited by the pulsed laser deposition (PLD) technique and were grown at various oxygen pressure ranging from 5 mtorr to 150 mtorr to investigate the effect of ambient O2 pressure on the structural properties of the films. We found that the lattice constant along the c-axis and the crystalline of ZnO films are sensitive to the O2 pressure.

대단위 병렬컴퓨터 시스템 노드구조 설계를 위한 워크벤치(SKYLAB)의 개발

윤현진,육은정,노권형,황대준 成均館大學校 科學技術硏究所 1993 論文集 Vol.44 No.1

Building the simulation environment of massively parallel computer systems has been recognized as a better approach over the experimentation on real machines to study extensively their architectural behaviours at a minimum cost. In this paper, we introduce a parallel processing workbench SKYLAB being implemented on DE C5000/25 and SPARCI workstations for design of node architectures featuring optimal organization for massively parallel processing. For the through analysis of the features of architectures in mind, the SKYLAB comes with thress major components: the compilerbackend translating single-threaded codes into their equivalent multithreaded codes, the node architecture emulator incopperating target CPU for program execution, and the graphic use interface for easy interpretation and expedating the analysis of the statitistics from the simulation runs. The design experience of the node architecture of the DAVRID multithreaded parallel processing computer using the SKYLAB examplifies how much effictively to make experiment on parallel simulations using this integrated toolset.

구강 편평세포암종에서 E-cadherin 및 β-catenin 발현의 변화 : Correlation with Histologic Features and p53 Expression

서진건,권창석,박진배,윤혜경,김우형,이희철 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.4

Objective : Altered expression of cell adheion molecules is associated with biologic behavior of tumor. The aim of this study is to evaluate the expression pattern of E-cadherin, β-catenin and p53 protein according to histologic grade and invasion pattern of squamous cell carcinoma of the oral cavity and the relationship between E-cadherin, β-catenin and p53 protein expression. Methods and Material : The materials were fifty seven cses of squamous cell carcinoma, and clinicl parameers such as age, sex, tumor location, stage and recurrence were recorded. Histologic review was done based on histologic grade and invasion pattern(nodular vs infiltrative). Immunohistochemical stains for E-cadherin and β-ca tenin were interpreted based on staining pattern as los of membranous expression and cytoplasmic expression and p53 protein expression was defined as positive if more than 10% of nuclei were reactive. Statistical analysis between E-cadherin, β-catenin and p53 protein expressions and histologic grade and invasion pattern and the relationship between E-cdherin, β-catenin and p53 protein expressions were perfomed. Results : There wa positive correlation between higher histologic grade and infiltrative pattern. Loss of membranous expression and cytoplasmic expression of E-cadherin were noted in 33.3% and 57.9%, respectively, and loss of membranous expression of E-cadherin showed increaing tendency in poorly differentiated carcinomas, however, there was no significant difference of cytoplasmic expression rate of E-cadherin according to histoogic grade. Altered expression of E-cadherin was more frequent in poorly differentiated carcinomas. Loss of membranous expression and cytoplasmic expression of E-cadherin were more frequent in carinomas with infiltrative pattern than in carcinomas with nodular pattern, but their diferences were not significant, Loss of membranous expression and cytoplasmic expression of β-catenin were observed in 19.3% and 80.7%, respectively. Loss of membranous expression of β-catenin howed no positive correlation according to histologic grade and invasion pattern, but cytoplasmic expression rate of β-catenin was higher in poorly differentiated carcinomas and in carcinomas with infiltrative pettern. p53 protein expression rate was 45.6%, and showed invreasing tendency in poorly differentiated carcinomas, but no significant relationship with invasion pattern. There was an inverse relationship of loss of membranous expression and cytoplasmic expression of E-cadherin and β-catenin. Altered expression of E-cadherin was related to cytoplasmic expression of β-catenin, however, there were no significant relationship between altered expressions of E-cadherin and β-catenin and p53 protein expression. Conclusion : In squamous cell carcinomas of the oral cavity, altered expression of E-cadherin and β-catenin was more frequent in poorly differentiated carcinomas and in carcinomas with infiltrative pattern and there was positive correlation betwween altered expression of E-cadherin and β-catenin. These findings suggest that altered expressions of E-cadherin and β-catenin may have a role in the development of squamous cell carcinomas with aggressive biologic behavior. but altered explosions of E-cadherin and β-catenin. These findings suggest that altered expressions of E-cdherin and β-catenin my have a role in the development of squmaous cell carcinomas with aggressive biologic behavior. But altered expression of E-cadherin and β-catenin might not be related to p53 protein expression. Further study on genetic mutation related to altered expression of E-cadherin and β-catenin will be needed

충남대학교 교내 산림환경 개선을 위한 경관 가치 평가

송형섭,박범진,권기원 忠南大學校 環境問題硏究所 1997 環境硏究 Vol.15 No.-

The purpose of this study is to obtain some useful informations for improving the campus forest landscape of Chungnam National University. Based on two kinds of surveyed data relating campus forest landscape resources and the respondents visual preference ratings, geographical features and physical characteristics of forest landscape are investigated. Twenty-four photos were taken for visual preference survey. With a total 100 respondents, relative scenic beauty of each forest scenes could be explained in terms of influence factors of physical characteristics. Three variables in model could be accounted for 65% of total variables in perceived forest scenic beauty. Results indicated that campus forest landscape must be improved greatly in the scenic views and so on. To improve current situation, some alternatives including improvement scheme and cost have to be proposed newly.

유전체의 과도 산란 해석을 위한 시간영역 결합 적분방정식

박재권,김형진,윤희상,정백호 湖西大學校工業技術硏究所 2003 工業技術硏究所論文集 Vol.22 No.-

In this paper, we propose a time domain combined field integral equation (TD-CFIE) formulation to analyze the transient electromagnetic response from three-dimensional dielectric objects. The solution method in this paper is based on the method of moments(MoM) that involves separate spatial and temporal testing procedures. A set of the RWG(Rao, Wilton, Glisson) functions is used for spatial expansion of the equivalent electric and magnetic current densities and a combination of RWG and its orthogonal component is used as spatial testing. We also investigate spatial testing procedures for the TD-CFIE to select the proper testing functions that are derived from the Laguerre polynomials. These basis functions are also used for temporal testing. Numerical results computed by the proposed formulation are presented and compared with the solutions of the frequency domain combined field integral equation(FB-CFIE).