연속 섬유강화 복합재료 리바 개발에 관한 연구

한길영,이동기,김성용 朝鮮大學校 機械技術硏究所 2000 機械技術硏究 Vol.3 No.2

This paper describes the need for a ductile Fiber Reinforced Plastic(FRP) reinforcement for concrete structures. Using the material hybrid and geometric hybrid, it is demonstrated that the pseudo-ductility characteristic can be generated in FRP rebar. Ductile hybrid FRP bars were successfully fabricated at 4mm and 10mm nominal diameters using an hand lay up method. Tensile specimens from these bars were tested and compared with behavior of FRP rebar and steel bar. The summarized results are as follows : The tensile strength of CFRP, KFRP and GFRP rebar with nominal diameter ψ4mm, respectively, showed 91.7kg/mm^2, 66.5kg/mm^2, 53.6kg/mm^2. The tensile strength of CFRP, KFRP, GFRP rebar with nominal diameter ψ10mm by the hand lay up method, respectively, showed 125.4kg/mm^2, 54.1kg/mm^2, 46kg/mm^2.

콘크리트 구조물용 GFRP리바의 기계적 특성에 관한 연구

한길영,이동기,김성용,전상기,최종대,박준식 조선대학교 에너지.자원신기술연구소 2000 에너지·자원신기술연구소 논문지 Vol.22 No.2

In this paper was studied on the mechanical characteristics of Glass Fiber Reinforced Plastics(GFRP) of the steel bar it is to replace The advantage of FRP such as high strength low weight and chemical inertness or noncorrosiveness can be fully exploited. GFRP bar were successfully fabricated at 10mm nominal diameters and hollow types using a pultrusion method Tensile and bending specimens from this bar were tested and compared with behavior of GFRP rebar and steel bar.

니트섬유강화 복합재료의 기계적 성질에 관한 연구

한길영,이동기,최병기,오환교,신용욱,전수영 조선대학교 에너지.자원신기술연구소 1999 에너지·자원신기술연구소 논문지 Vol.21 No.2

Using conventional textile techniques such as weaving, braiding, knitting and stitching it is possible to produce a wide range two and three dimensional fiber preforms. However, so far only a limited attention has been given to knitted fabrics in composite industry. This is mainly due to the opinion that knitted fabric reinforced composites posses low mechanical properties owing to their looped fiber architecture. But it is possible to obtain desired mechanical properties by selecting proper knitted fabric structure. In this paper, tensile failure load and displacement of one yarn, four yarns and knitted fabrics of ten yarns of kevlar fiber were determined experimentally in the unidirection. Mechanical properties of plain weft knitted fabrics reinforced composite intrusion beam for car side door application were investigated experimentally, which compared with desire value of American Fedral Motor vehicles Safety Standard (FMVSS) and presented the results.

알루미늄 샌드위치 판넬의 전자파 차폐효과

한길영,김진석,안동규 朝鮮大學校 機械技術硏究所 2006 機械技術硏究 Vol.9 No.1

The objective of this research is to investigate the electromagnetic interference(EMl) shielding characteristics of aluminium sandwich panel. We fabricated aluminium sandwich panel with core material Ni-Cu fabrics. The measurements of shielding effectiveness(SE) were carried out frequency range 300MHz -1 GHz for commercial purposes such as electric or telecommunication devices. The return loss and loss due to absorption were also measured as a function of frequency in the microwave(300MHz-1GHz) region. It is observed that the SE of the composites is the frequency dependent, increases with the increases in filler loading. The Ni-Cu fabrics core material showed higher SE compared to that of AI. The aluminium sandwich panel was shown to exhibit up to 40dB of SE.The results indicate that the composite having higher filler loading can be used for the purpose of EMI shielding as well as for some microwave applications.

딤플형 내부구조체를 가진 Isb 판넬의 정적 굽힘 특성

안동규,문경제,한길영 朝鮮大學校 機械技術硏究所 2006 機械技術硏究 Vol.9 No.1

본 연구에서는 덤플형 내부 구조제를 가진 ISB 판넬의 굽힘 및 파손 특성을 분석/고찰하고자 한다. 딩플형 내부 구조체를 가진 ISB 판넬의 설계조건에 따른 변형 형상, 최대하중 및 최대하중에서의 변위와 같은 특성치 및 파손 형태를 분석하기 위하여 정적 3접 굽힘 시 험을 통한 하중-변위 곡선과 파손 형상을 얻었다. 또한, 본 실험 결과를 이용하여 ISB 판 넬 설계 변수의 굽힘 특성 및 파손 모드 영향성을 분석하였다. 본 연구 결과 딩플형 내부 구조체를 가진 ISB 판넬의 굽힘 및 파손 특성은 덤플형 내부구조체의 반경비와 ISB 판넬 의 재료 방향에 따라 제어 가능함을 알 수 있었다. The objective of this pater is to investigate into bending and failure characteristics of ISB panel with dimple shapes as inner structures. Through three-points bending test, the force-displacement curve and the failure shape are obtained to examine the deformation pattern, characteristic data including maximum load and displacement at the maximum load and failure pattern for the ISB panel. In addition, the influence of design parameters for ISB panel on the bending stiffness and failure mode has been found. From the results of the experiments, it has been shown that bending and failure characteristics of the ISB panel can be controlled by the ratio of radius and the direction of the material.

국악감상수업을 위한 멀티미디어 학습자료개발 : 초등학교 3, 4학년을 중심으로

김동현,채길룡,오한숙 光州敎育大學校 初等敎育硏究所 2002 初等敎育硏究 Vol.17 No.-

Emphasis of Korean classical music has been greatly placed on the music course since the 6th curriculum, and it is more laid in the 7th curriculum; the content is more detailed and Korean classical music of materials in music textbook amounts to 38% - increased 10% compared to the 6th curriculum. Now is rather to devise data to enable 'esthetical experience' of Korean classical music by providing certain 'experience activity' program and develop data to be effectively used in the field than to discuss weight of Korean classical music education. Therefore, this study attempts to develop appreciation data with computer and multimedia to be used as teaching and learning data in the appreciation area, which specially teachers suffer from how to guide, among several areas of Korean classical music. For such objective, the music course of the third and fourth grader was analyzed to draw a teaching and learning objective and a viewpoint of appreciation, materials of Korean classical music were examined in textbook, and various multimedia data and related website to improve teaching effect were surveyed, arranged and made into PowerPoint data. In addition, students' interest in learning and results of the performance evaluation were compared by application of the produced multimedia data to the actual field class to verify effect of data use. As a result of comparison of results of students' interest in Korean classical music appreciation class before and after application of the produced data, use of the data influenced improvement of students' interest in Korean classical music class. Also, as a result of making the field teachers who are interested in Korean classical music class examine the data, they responded that the data is very useful for improvement of the field Korean classical music class. Results of this study are summarized as follows; A. In Korean classical music class, data enabling broad experience and musical practice through application of the varied multimedia dta out of monotonous listening-centered class was developed. B. Out of the limited educational environment by improvement of teaching and learning method with ICT, self-directional learning was enabled in consideration of learner's level and interest.

RV 형 자동차 Console Box 사출성형공정 해석 및 최적 게이트 선정

안동규,김대원,한길영 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1

본 연구에서는 BE 분석하였다. 또한, 본 대상 금형의 게이트 위치와 개수의 제품 생산성 영향성 및 형체력 상관관계를 분석하였다. 최종적으로 해석결과와 분석결과들을 이용하여 제품에 적합한 최적의 게이트 M 기반의 사출성형 해석을 통하여 RV 형 자동차 콘솔 박스(Console Box) 제작용 사출성형 금형의 게이트 위치와 게이트 개수를 결정하였다. 사출성형 해석시 금형 설계 변수를 게이트 위치와 개수로 선정하고, 게이트 위치와 개수의 변화에 따른 제품의 충진 특성, 압력 특성 및 제품의 웰드라인 생성과 수축/팽창 특성 변화를 정량적으로 위치와 게이트 개수를 도출하였다. The objective of this research work is to determine the gate location and the number of gates of the injection mould for the console box of RV cars using injection molding analysis based boundary element method (BEM). The gate location and the number of gates have been selected as design parameters of the mould. The influence of the gate location and the number of gates on filling characteristics, pressure characteristics, the formation of weld lines, and volumetric shrinkage/expansion characteristics has been quantitatively investigated. In addition, the effects of the gate location and the number of gates on the productivity of products and the clamping force of the mould has been evaluated. Finally, the optimum gate location and the number of gates for the target mould have been obtained.

섬유강화 복합재료의 사출성형에 있어서 섬유배향에 미치는 성형조건의 영향

이동기,한길영,김성용 朝鮮大學校 機械技術硏究所 2000 機械技術硏究 Vol.3 No.2

Injection molding is a very important industrial process for the manufacturing of plastics objects. During an injection molding process of composites, the fiber-matrix separation and fiber orientation are caused by the flow of molten polymer/fiber mixture. As a result, the product tends to be nonhomogeneous and anisotropic. Hence, it is very important to clarify the relations between separation orientation and injection molding conditions. So far, there is no research on the measurement of fiber orientation using image processing. In this study, the effects of fiber content ratio and molding condition on the fiber orientation-angle distributions are studied experimentally. Using the image processing method, the fiber orientation distribution of weld-line parts in injection-molded products is assessed. And the effects of fiber content and injection molding conditions on the fiber orientation functions are also discussed.

수분흡수가 섬유강화 고분자 복합판의 기계적 성질에 미치는 영향

김혁,한길영,이동기 조선대학교 생산기술연구소 1995 生産技術硏究 Vol.17 No.1

Nowadays, it is common and becoming more popular to use fiber-reinforced polymeric composites(FRP) in order to reduce the lightweight of the structures such as marine vehicles, automobiles and airplane. It investigates the residual strength characteristics of composite under the environment of high temperature and humidity. The residual strength of FRP is known to be greatly influenced by temperature, humidity etc. In this context, the hygrothermal effect of changing the fiber contents and orientation are investigated in order to provide better residual strength characteristics. When exposed long terms in high temperature and humidity, the randomly oriented composites is to be more stable than the unidirection one.

수지말단부 손상의 분류와 재건

박대환,한동길,안기영 대한성형외과학회 1992 Archives of Plastic Surgery Vol.19 No.3

Finger tip injuries are in increasing tendency and the treatment must be focused toward preserving length and providing normal sensitivity. The 61 injured digits distal to DIT joint in 49 patients were managed in various procedures from May, 1990 to June, 1991. The authors classified the injured digits into 6 groups and selected the best surgical procedures according to the extent of the injuries. The 6 groups were : A. Volar skin and pulp loss without exposed bone B. Large volar skin and pulp loss with exposed distal phalanx C. Straight-transecton involving nail bed injury. D. Dorsally directed injury with little remaining nail bed E. Germinal matrix injury F. Injury at DIT joint level Tentatively recomonended surgical procedures by the extent of injury were : 1. Secondary intention or skin graft for level A 2. Local flap coverage for level B 3. Composite graft or Local advancement flap for level C 4. Local flap coverage or primary closure after bone shortening and residual nail ablation for group D 5. Micro-replantation or distant flap or local flap according to the state of the injury for group E and F