원위 대퇴골의 고립성 골연골종에서 발생한 속발성 연골 육종 1례 보고

정필현,황장수,강석,김용민,오형호,채동주,김종필 동국대학교 경주대학 1996 東國論集 Vol.15 No.-

연골육종은 비교적 서서히 자라며 늦게 전이하는 악성 연골 종양으로 알려져 있다. 골 연골종에서 발생한 속발성 연골육종은 발생빈도는 드물며 타부위로의 전이가 적고 악성도가 낮은 경우가 많아 적합한 수술적 치료로서 좋은 예후를 보이는 것으로 보고되고 있다. 본 동국대학교 정형외과학 교실에서는 우측 대퇴골 원위부 골간단부에 생긴 고립성 골 연골종에서 이차적으로 발생한 연골육종을 치험한 바 문헌고찰과 함께 보고하는 바이다. A case of Secondary Chondrosarcoma Arising from Solitary Osteochondroma of the Distal Femur Department of Orthopaedic Surgery, College of Medicine, DongGuk University Phil Hyun Chung M.D., Jung Su Hwang M.D., Suk Kang M.D., Yang Mln Kim M.D., Hyung Ho Oh M.D., Dong Ju Chae M.D., Jong Pil Kim M.D. Chondrpsarcoma is a malignant cartilage-forming tumor that grows slowly and metastasis of this tumor occurs in late stage. Secondary chondrosarcomas arising from a solitary osteocartilaginous exostosis are rare and those have a better prognosis than other chondrosarcomas, and they rarely metastasize. We present our experience with a case of secondary chondrpsarcoma arising in solitary osteochondroma of distal metaphysis of right femur with clinical details.

APCVD법을 사용한 보론 포스파이드의 증착 및 특성에 관한 연구

김순영,문병필,윤여철,전호승,김철주 서울시립대학교정보기술연구소 2001 정보기술연구소 논문집 Vol.3 No.-

Boron Phosphide films were deposited on the glass substrate at the low temperature, 550℃, by the reaction of B₂H_6 with PH₃ using CVD. N₂ was employed as carrier gas. The reactant gas rates were 50 ㎖/min for B₂H_6, 50 ㎖/min for PH₃ and 1.5ℓ/min for N₂. The films were annealed for 1hour, 3hours in N₂ambient at 550℃. The deposition rate was 1000Å/min and the refractive index of film was 2.6. The measurement of XRD shows that the films have the preferred orientation of (1 0 1). The data of VIS spectrophotometer show 75.49% for as-deposited, 76.71% for 1hr-annealed and 86.4 % for 3 hrs-annealed. The data of AFM show 73Å for as-deposited, 88.9Å for 1hr-annealed and 220Å for 3hrs-annealed. Also, The data of the secondary electron emission rate(γ) s how 0.317 for as -deposited, 0.357 for 1hr-annealed and 0.537 for 3hrs-annealed. And, The film shows the surface deposited thin film, bu using FT-IR, has the O-H bond and this bond is greatly decreased as annealing.

DRAM에서의 고전압 발생기

김필중,윤중현,라경태,김경호 木浦大學校 情報産業硏究所 1999 情報産業硏究誌 Vol.7 No.-

Abandoned bad DRAM chips have increased by 1-2 bit defective cells after package with high integrated memory. To repair this 1-2 bit defective cells. an antiques repair method of electrical repair method is using instead of laser repair method. This antiques repair method require high voltage over 7v to program antiques element. In this paper, the high voltage generated in chip without added pin or pad. The high voltage generator was designed using not conventional MOS devices but pn diodes and stacked comb capacitors. Threshold voltage of pn diode is about 0.8v. and stacked comb capacitor have much capacitance of 5-6 times than conventional planar capacitor. The output voltage of designed high voltage generator are 7.4-8.4v. and the output current driveability is maximum 480㎂.

동기정류방식에 의한 하프브리지 컨버터의 효율개선에 관한 연구

김용,고승모,백락준,김필수,윤석호 東國大學校 1999 東國論叢 Vol.38 No.-

The effort to increase operating frequency in order to reduce weight, size and coast of magnetic and filter elements is constantly hampered by higher switching stresses and switching losses. And the evolution in the digital integrated circuits in demanding lower power supply voltage. In a few years, 3.3V may be standard. In converters with such a low output voltage, it is quite difficult to achieve high efficiency due to the rectifier diodes of the output stage what limits the reduction converter size. To over come theses obstacles, this paper proposes the ZVS Half-Bridge converter using Self-driven Synchronous Rectifier. Using resonant condition of the transformer primary side series equivalent inductance and parasitic capactiance of the switching device, the circuit operates in zero-voltage switching. The steady state equation and ZVS condition are derived. The Zero Voltage Switching is analyzed taking into account the effect of the parasitic capacitance of the MOSFET rectifiers on the transformer secondary side. The Zero voltage Switching condition is established. Simulation and experimental result are compared.

고효율 DC/DC컨버터 제작을 위한 동기정류기 도전 손실 해석

윤석호,김용,백수현,김필수 동국대학교 산업기술연구원 1999 산업기술논문집 Vol.14 No.-

최근 반도체 소자의 제조기술 발달로 정보통신기기 등에 사용되는 온보드(on-board) 컨버터의 전원전압은 3.3V 또는 1.5V의 저전압 전원이 사용된다. 이러한 저전압 전원방식은 온보드(on-board) 컨버터의 정류기단 전력손실이 증가하게 되어 시스템의 높은 효율을 얻기가 어렵게 된다. 낮은 전원전압 방식일수록 정류기단에서 전력손실은 더욱 증가하여 컨버터의 효율은 낮아진다. 고전력밀도의 정류기단 구성을 위하여 출력단에 다이오드 대신 MOSFET 자기구동 정류기를 사용한다. 그러나 MOSFET 자기구동 정류기의 전력손실은 2차측 구동전압의 형태나 기생인덕턴스의 영향을 받게 된다. 따라서 불연속에서는 기생인덕턴스에 의한 MOSFET와 쇼트키 다이오드의 도통주기의 변화가 MOSFET 자기구동 정류기의 전력손실에 미치는 영향을 분석하였으며, 그 결과 기생인덕턴스의 크기를 감소시켜 MOSFET의 도통주기를 증가시킴으로써 MOSFET 자기구동 정류기의 전력손실을 최소화하였다. Recently, new trend in telecommunication device is to apply low voltage, about 3.3V-1.5V. However, it is undesirable in view of high efficiency and power desity which is the most important requirement in the distributed power system. Rectification loss in the output stage in on-board converter for distributed power system are constrained to obtain high efficience at low output voltage power supplies. This paper is investigated conduction power loss in synchronous rectifier with a parallel connected Schottky Barrier Diode(SBD). Conduction losses are calculated for both MOSFET and SBD respectively. The SBD conduction power loss dissipates more than the MOSFET rectifier conduction power loss.

VOD에 적용 가능한 인증 프로토콜 실현

염흥열,윤호선,김상필 순천향대학교 부설 산업기술연구소 1997 순천향 산업기술연구소논문집 Vol.3 No.2

In this paper, we present the access control technique which is one of the essential functions for VOD. As the BISDN widely spreads, need for VOD services will rapidly be increased. Access control technique is needed to allow VOD system to prevent the unauthorized persons from using the unauthorized service. We have implemented the authentication scheme with C language on UNIX. We have used 768-bit RSA signature scheme and MD5 hash function for implementing the authentication scheme.

초음속 유동장에 놓인 쐐기 주위의 유동 특성

신완순,신필권,이택상,김윤곤,박종호 忠南大學校 産業技術硏究所 1998 산업기술연구논문집 Vol.13 No.1

Theoretical analysis and experiment for supersonic flow around the wedges have been conducted. Wedges are being used as a means of measuring a flow direction, Mach No., a basic study of inlet or combustion chamber of ramjet and scramjet engine. We use a shock tunnel to get a supersonic flow conditions and schlieren system to visualize supersonic flow field around wedge. Numerical simulation is also conducted by Harten-Yee type 2nd-order Total Variable Diminishing(TVD) scheme and oblique shock theory. Comparison of calculated results with experimental data is in good agreement.

무선 근거리 통신망에 적용 가능한 정보보호 규격

염흥열,윤호선,김상필,이강석 순천향대학교 부설 산업기술연구소 1997 순천향 산업기술연구소논문집 Vol.3 No.2

본 논문에서는 무선 근거리 통신망에서의 프로토콜 구조를 분석한 후, 이를 바탕으로 무선 근거리 통신망에 적용 가능한 정보보호 규격을 제시하고, 기존의 보안 알고리듬의 문제점을 제시하며 그에 대한 해결 방안을 제시하여 정보보호 서비스를 실현하기 위한 정보보호 메카니듬을 도출한다.

Regioselective Addition Reactions of the Organoindium Reagents onto α,β-Unsaturated Ketones

Lee, Phil-Ho,Kim, Hyun,Lee, Koo-Yeon,Seomoon, Dong,Kim, Sun-Dae,Kim, Hee-Chul,Kim, Hyun-Seok,Lee, Mi-Ae,Shim, Eun-Kyong,Lee, Seok-Ju,Kim, Mi-Sook,Han, Mi-Jeong,Noh, Kwang-Hyun,Sridhar, Madabhushi Korean Chemical Society 2004 Bulletin of the Korean Chemical Society Vol.25 No.11

Regioselectivity on the reactions of ${\alpha},{\beta}$--enones with organoindium such as in situ generated allylindium and allenylindium was systematically studied in the presence of TMSCl as an additive. Treatment of 2-cyclohexen-1-one, carvone, 2-cyclohepten-1-one, and chalcone with allylindium reagent produced 1,4-addition products in good yields, while 2-cyclopenten-1-one, 2-methyl-2-cyclopenten-1-one, 4,4-dimethylcyclohexen-1-one, 3-nonen-2-one, 4-hexen-3-one, and 4-phenyl-3-buten-2-one afforded 1,2-addition products. Indium reagent derived from indium and propargyl bromide in Grignard type gave addition products in good yields, under which the successive addition of ${\alpha},{\beta}$-enone and TMSCl were necessary. Although organoindium reagent derived from propargyl bromide produced propargylated compound in Grignard type except 2-cyclohepten-1-one, indium reagent obtained from 1-bromo-2-butyne having ${\gamma}$-methyl group gave allenylated product inBarbier type.

Active Air Flap을 장착한 차량의 주행저항 및 엔진룸 유동해석

김태경(Tae-Kyung Kim),최중근(Joong-Keun Choi),김정현(Jung-Hyun Kim),조준호(Jun-Ho Cho),이영빈(Yeong-Bin Lee),김규홍(Kyu-Hong Kim),이동호(Dong-Ho Lee),김진필(Jin-Phil Kim),이준호(Jun-Ho Lee) 한국자동차공학회 2012 한국자동차공학회 부문종합 학술대회 Vol.2012 No.5

This paper describes on numerical studies on improvement of car engine room and aerodynamic drag for CO2 reduction with an active air flap. The numerical models were full scaled car of YF SONATA that has detailed car engine room with active air flaps. An base model of YF SONATA was compared with a change grill model of that which has active air flaps. As a result, the aerodynamic drags were compared depending on the operating conditions and times of active air flap on upper and under grill. An engine room cooling efficiency which were internal temperature, static pressure and stream line was shown according to those flap conditions.