Cu(001) 표면에 성장시킨 Ni 초박막의 구조 연구

閔恒基,李圭燮 弘益大學校 科學技術硏究所 1995 科學技術硏究論文集 Vol.6 No.-

The growth of Ni deposited on Cu(001) surface at room temperature was studied by LEED(Low Energy Electron Diffraction) I/V analyses. For the Ni thin films of thickness from 1 ML(mono layer), the subsurface Ni layer below 1 ML Cu surface layer is found to be the optimum structure. This result is also consistent with the growth mode predicted by the first principles total energy calculation.

생체분해성 고분자를 이용한 사시수술용 제형개발 및 효용성에 대한 연구

민병무,김용백,김승영,김창식,박근성,길숙종,조항진,이성복,노승무,송규상,강대영,조준식,양준묵,정경수,최선웅,이진호,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

A new device, muscle clamping system was developed to facilitate exact quatifying technique A strabismus surgery, and reduce the risk of complications. The device is composed of a lower fixing body with three jaws and an upper supporting body. They are used to clip an extraocular muscle and fix it to the sclera with a single bite. Superior rectus recession on 16 rabbit eyes were performed with this new device. Conjunctival injection, muscle adhesion strength, and light microscopic findings were examined at 1, 2, 4 and 8 weeks postoperatively. The Conjunctival injection were minimal, adhesion power ranged from 420 to 600 gram gravity, which is sufficient in withstand the normal pull of human extraocular muscle. In microscopic exam, some Inflammatory cells and fibrosis were found. The new device was technically easy, fast, and accurate, so it may be useful in stabismus surgery.

진공기술과 표면과학에 관한 고찰

閔恒基 弘益大學校 1989 弘大論叢 Vol.21 No.2

In this paper, vacuum technology with kinematic motion of gas and vacuum Pumps is briefly studied. Also the importance of studying surface science is mentioned. The techniques of surface study are explained. The present level of surface study in Korea is also mentioned in a viewpoint of basic science and technolog development.

피브린 파이버의 영률 측정

閔恒基 弘益大學校 科學技術硏究所 2005 科學技術硏究論文集 Vol.16 No.-

Fibrin clots perform the mechanical task of creating blockage that stems blood flow in vivo. to understand the forces that contribute to clot strength and elasticity, we measured of fibrin fiber Young's modulus using a combined atomic force microscope(AFM) and optical microscope system. With this system, we are able to image fibrin fibers in aqueous conditions and monitor the deformation of the fiber while measuring the applied force simultaneously. Specifically, we have determined breaking strain and Young's modulus of fibrin fibers for across-linked versus uncross-linked fibrin. Normal recombinant fibrinogen was clotted by thrombin with/without Factor XIII. Recombinant fibrin fibrs were fluorescently labeled with quantum dots. We have observed breaking strains of 90% for uncross-linked fibers and 300% for crosse-linked fibers. We have also determined Young's modulus for cross- and uncross-linked fibers by 0.4 MPa and 2.7 MPa respectively. Thrombin polymerized fibrin fibers show largely elastic behavior.

생체분해성 안과제형의 안구내흡수정도와 안독성

민병무,김용백,박근성,송규상,양준묵,이성복,조항진,길숙종,김승영,김학용 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

An improved retinal tack can be used to fix the retina in complicated retinal detachment and proliferative vitreoretinopathy. We used the retinal tack made by biodegradable polyglycolic acid, polylactic acid and copolymers. The tacks with polyglycolic acid were placed in the retina the right eyes of 10 rabbits as group 1, with polylactic-polyglycolic acid copolymers as group 2 in each left eyes. We examined the absorption rates and degree of intraocular inflammation at 1 day, 1, 2, 4, and 8 weeks and compared both eyes. The tacks were absorbed with time in both eyes, but more rapid in copolymers. And there was no inflammation in both eyes. Now, this study will be a base on the drug delivery system in intraocular pharmacological and surgical management.

LEED를 이용한 Co/Cu(001) 초박막의 구조 연구

閔恒基,安秉男 弘益大學校 科學技術硏究所 1998 科學技術硏究論文集 Vol.9 No.1

We studied the growth mode and stoichiometry of ultrathin Co film on Cu(001) single crystal surface by Auger electron spectroscopy and dynamin LEED analysis. I/V characteristics of LEED spot of ultrathin Co/Cu(001) system were obtained by video LEED system and analized by tensor LEED program and applied ATA (average t-matrix approximation). The structure and compositional variation as a function of temperature were traced. We found that a significant amount of Cu atom was segregated from the substrate to the surface of the Co film at room temperature.

주사 투과 현미경 제작

閔恒基 弘益大學校 科學技術硏究所 1999 科學技術硏究論文集 Vol.10 No.1

We developed scanning tunneling microscope(STM) which could operate in ultrahigh vaccum as well as in air pressure, over wide range of temperatures extending from room temperature to liquid-nitrogen temperature(77K). Designed STM was consist of a compact and rigid enough head in order to reduce and damp the external vibration. Tube-shaped scanner, and the stick-slip walker were adopted to approach the tip to the sample surface. The STM was tested for scanning image of highly oriented pyrolytic graphite(HOPG) as a preliminary experiment in air.

K/W(110)의 표면 및 계면에 관한 연구

閔恒基 홍익대학교 산업기술연구소 1993 産業技術 Vol.2 No.-

The purpose of this study is to determine reactivity of K/W(110) interfaces which were investigated by Auger electron spectroscopy(AES) and angel resoved ultraviolet photoemission spectroscopy(ARUPS). Clean Auger spectra of potassium deposited tungsten were obtained. The surface contours and work function for the surface states were investigated using ARUPS. After potassium deposited on the W(110) surface, the feature of Fermi contours were changed. Electron pockets were extended clearly, but hole pockets were disappeared except one which is around N―

스크립트 MIB을 이용한 분산 망 관리

이길홍,김민수 서울産業大學校 2001 논문집 Vol.52 No.1

현재 급성장하고 있는 인터넷망을 관리하는데 있어, 확장성과 효율성, 유연성을 갖는 네트워크 및 시스템 관리 방안이 필요하게 되었다. 이를 위해서 동적으로 변하는 네트워크 환경에 맞도록 관리 기능을 분산시키고, 관리 기능을 전달하고 실행할 수 있는 새로운 분산관리 구조가 필요하다. 본고에서는 IETF 스크립트 MIB을 이용한 분산 망 관리 구조를 이용하는 관리 방안을 구현해 본다. 실험한 망 관리 구조는 스크립트 MIB을 제어하는 관리시스템을 구현하고, 관리 기능의 하나인 구성 관리 기능과 성능 관리를 수행하는 에이젼트의 기능을 제안하고 구현하였다. 제안한 구조를 이용하여 실제 인터넷망에서 응용하여 실험하였다. To ensure the scalability, efficiency and flexibility of network and systems management platforms of today's growing Internet networks, distributed management systems are strongly required. To solve this problem, it is required that a distributed management architecture that delegates and performs management functions for managing dynamically changed network environments We present the new architecture for managing distributedly using the IETF script MIB. We implemented and applied proposed scripts to the applications of monitoring and configuring management of the Internet.

디지털공제방사선촬영술을 이용한 치근단 흡수의 평가

허민석,이삼선,이경희,최항문,최순철,박태원 대한구강악안면방사선학회 2001 Imaging Science in Dentistry Vol.31 No.1

Purpose : This study was performed to compare the diagnostic ability of conventional intraoral radiographs with that of digital subtraction image and to assess the quantifying ability of digital subtraction image for simulated apical root resorption Materials and Methods : Conventional intraoral radiographs and digital images of ten sound maxillary central incisors and those with simulated apical root resorption were taken with varying horizontal and vertical angulations of the x-ray beam. The diagnostic accuracy to detect the lesion was evaluated on conventional intraoral radiographs and digital subtraction images by ROC analysis. The amount of simulated apical root resorption was also estimated on the reconstruction images by Emago□ and compared with actual amount of tooth loss using paired t-test. Results : The diagnostic accuracy of conventional intraoral radiographs to detect the apical root resorption was low(ROC area = 0.6446), and the sensitivity and the specificity of digital subtraction images were 100%, respectively. The calculated amounts of apical root resorption showed no statistically significant difference with the actual amounts of the lesion (p 〉 0.05). Conclusion : Digital subtraction radiography is powerful tool to detect the small apical root resorption, and quantitative analysis of small amounts of the lesion can be evaluated by digital subtraction radiography.(Korean J Oral Maxillofac Radiol 2001;31:51-5)