AISI 4340 ?? 鋼의 衝擊에너지와 ??값 사이의 相互關係에 관한 硏究

성낙원,심봉식 東亞大學校 大學院 1986 大學院論文集 Vol.11 No.-

Charpy V-notch impact test and compact tension test in the enviroment of high and low temperature on the specimens of N?C?M? steel have been conducted. This paper is to evaluate the correlation between CVN and K? test results as a function of temprature. The results of this study are as follows. 1. The transition temperature by the effect of impact absorption energy from lower shelf to upper shelf have the tendencies of increasing with the incrase of temperature. 2. The value of K? measired from compact test is linearly increased with the increase of temperature. 3. The empirical correlation between impact energy and value of K? is obtained as K?/E=3.2545(CVN)-5.0064 and the rates of the erro from the test results are within 7pe cent.

높이뛰기의 바 넘기 동작을 위한 각운동량 분석

성낙준 한국운동역학회 2004 한국운동역학회지 Vol.14 No.3

R. J. SUNG. Analysis of the Angular Momentum for the Bar Clearance Motion in the Fosbury Flop. Korean Journal of Sport Biomechanics, Vol. 14, No. 3, pp. 119-134, 2004. The purpose of this study was to analyze the angular momentum characteristics of the Fosbury Flop high jump and the role of the body segments for the production of 3 angular momentum components. The subjects were three male jumpers who were former Korean national team players. Their jumping motions were analyzed using the DLT method of three-dimensional cinematography. The conclusions were as follows. 1. All the forward angular momentum needed to clear the bar was created in the take-off phase. Take-off leg was the great contributor of the forward angular momentum. On the other hand, free leg produced large opposite angular momentum. 2. All subject had some lateral angular momentum before the take-off phase. Head and free leg had major contribution to the lateral angular momentum production. Take-off leg produced opposite angular momentum. 3. All subject had some twisting angular momentum, which make the back of the athlete turn to the bar, before the take-off phase. Free leg was the major contributor of the twisting angular momentum. Head and trunk was the second contributor of the twisting angular momentum. 4. Total angular momentum needed to clear the bar had no significant correlation to the jumping height. 5. Subject who made excessive angular momentum showed different pattern of angular momentum production and had a poor record compared to other subject.

골프 클럽의 스윙궤도와 스윙면에 대한 고찰

성낙준 한국운동역학회 2004 한국운동역학회지 Vol.14 No.1

R. J. Sung. A Study on the Swing Path and Plane of the Club in Golf Swing. Korean Journal of Sport Biomechanics, Vol. 14, No. 1, pp. 99-115, 2004. In order to know the correct swing methods in golf swing, it is important to understand the whole swing path but also the concept of swing plane. But, most amateur golfers don't know the concept of swing plane well. Therefore this study was trying to make a good material that makes the concept of swing plane easy to understand. A good swing motion data was obtained from a professional golfer using the three dimensional DLT method. This swing motion was divided into 10 phases and evaluated using the concept of swing plane. The result of the analyze show a good matches between the path of the club and swing plane. This result was summarized as a 3 dimensional graphics to provide a good material to teach the golf swing well.

AISI 4340鋼의 引張特性 및 破壞靭性에 미치는 溫度의 影響에 관한 硏究

성낙원,심봉식 동아대학교 공과대학 부설 한국자원개발연구소 1991 硏究報告 Vol.15 No.1

The K_(IC) value derived from CVN test were considerably different from measured value and it was difficult to predict the correct K_(IC) value of the materials under consideration. Compact tension and Charpy V―notch test in the invironment of high and low temperature on the specimen of AISI4340 steel have been conducted. The results may be sumerized as follows. The transition temperature by the impact absorbation energy range from - 50℃ and 150℃ and the impact energy from lower and high shelf have a tendencies of increasing with increase of the temperature. The measured K_(IC) value from CT test linearly increased with the increase of temperature. The K_(IC) value from the test fomular were derived and the error are within 6.8% against measured K_(IC) value.

인체 공중 동작 시뮬레이션 프로그램 개발

성낙준,권영후 한국운동역학회 1994 한국운동역학회지 Vol.4 No.2

A comprehensive simulation software package was developed in C base on the work done by Yeadon et al.(1990) and Kwon (1993a) in the aim of making it easy to apply the experimental simulation technigues to the human airborne movement studies. This package consists of 3 programs: simulation variable computation program (PREP), simulation program (SIM) and the 3-dimensional graphic program (3DMAN). All programs are driven by an easy-to-use menu system and written compatible to KWON3D Motion Analysis Package Version 2.1 (Kwon, 1993b). Program PREP consists of 4 menus: `Edit Data´, `Prepare´ `Angular Momentum´ and `Optimization´. The `Edit Data´ environment is an editor for the lengths of the segments and body lines. The `Prepare´ menu computes the internal orientation angles of the segments while the `Angular Momentum´ menu computes the mean airborne angular momentum of the body and other initial conditions such as the initial position and velocity of the body CM and the initial external orientation of the body. The `Optimization´ menu performs angular momentum optimization proposed by Kwon (1993a). A geometric 15-segment body model - Yeadon-Kwon model (Kwon, 1993b) - with at most 38 degrees of freedom including 3 external orientation angles (somersault, inclination and twist angles) was employed to compute the simulation variables. SIM consists of 2 menus: `Edit Angles´ and `Simulate´. The `Edit Angles´ environment is an editor for the internal orientation angles of the segments. Users can intentionally manipulate the internal orientation angles for the simulation of modified trials. The program displays time-angle curves segment by segment. The `Simulate´ menu actually performs simulation. The initial conditions can be directly manipulated in the program menu environment. The simulation program was tested by several theoretical configurations to screen out the flaws in the theory and to isolate coding mistakes. The simulated results were compared with the predicted results and the program showed good agreements between the simulated results and the theoretical predictions. The simulation program was then applied to several gymnastic maneuvers and springboard dives for testing. 3DMAN was developed in the extension of the traditional `Stick Figure´ graphics. The program is segment-oriented and the 3-D shape of each segment is defined defined independently in a graphic model file to allow the users to use different body models with different, combinations of segments. The model file was designed easy to edit so as to allow the users to change the graphic model easily to meet their specific needs. The graphic model file can be edited using any text editor such as `EDIT´ of DOS. Once the `3-D Graphics´ option is activated followed by the registration of the graphic model files, the program draws the 3-D shapes of the segments whose model files are registered. All the graphics-related menus including registration of the segment graphic model files are accessible within the graphic environment.

축방향의 압축하중을 받는 얇은 원통 "쉘"의 좌굴에 관한 실험적 연구

成洛元 東亞大學校 大學院 1981 大學院論文集 Vol.5 No.-

An experimental study of the buckling of thin cylindrical shell under the axial compression was carried out. Buckling procedure were obserbed and the results obtained for the buckling stress were compared with theoretical value and approximate soulution of the exisiting literature. The test model of aluminum alloy were used. From this study, the results are as follows; Buckling behavior is a dynamic procedure combinded with potential change due to the bending energy stored by the successive compression load. The pattern of buckling wave formed in rhombic figure and the length of these wave in axial direction and circumferential direction were same. Buckling of thin cylindrical shell occured in the limit of elasticity and buckling load were less the theoretical balue. The results obtained were good agreement with the approximate solution and emperical formula for the buckling load be induced in the form

다단변동/충격하중하의 탄소섬유강화 복합재료의 피로강도 특성 및 잔류강도 저하거동에 관한 연구

성낙원,이수진 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.-

Under the multi-step loading and impact loading, similar to real loading, fatigue tests have been carried out to examine the characteristics of a fatigue strength and a fatigue life and the degradation of the residual strength in carbon-epoxy composite materials. Two different shape of test specimen and test methods were used and the theory of cumulative damage and the residual strength degradation was applied to the test data of two parameter Weibull distribution. The static ultimate strength of the test piece used here in is observed to be relatively higher than that of existing composite materials, while fatigue life is shorter than that of estimated by residual strength degradation model when the stress level above 0.62. The fatigue life of the materials tested were observed the one of the high-low multi-step was longest and the one of the low-high next compared by Miner's value. It is proven that the prediction of fatigue life by the analysis of the theory of cumulative damage and degradation is resonable.

양 · 한방 협진의료시스템의 운영과 실태

이상락 대구보건대학 2009 대구보건대학 論文集 Vol.29 No.-

炭素纖維强化 複合材料의 機械的 强度特性 및 疲勞壽命豫測에 관한 硏究

成洛元,沈奉植 동아대학교 공과대학 부설 한국자원개발연구소 1993 硏究報告 Vol.17 No.1

An experimental investigation was performed on the carbon-epoxy resin composite materials under constant stress amplitude and two step loading high low type and low high type loading, to study the mechanical properties and fatigue properties. Different shape of test specimen and test methods were used for evaluating the dispersion pattern in fatigue life and its reliability. A statistical approach was applied to test data with the aid of two parameter Weibull probabilities. It is indicated that the dispersions in the fatigue life are more wider at the high stress amplitude than at the low stress level and fatigue life was extended in the two step loading. Experimental data for the fatigue life showed good agreement with the one of the theoretically predicted at high stress level.

운동역학의 교육과 연구용 도구로서 Mathcad의 유용성

성낙준 한국운동역학회 2004 한국운동역학회지 Vol.14 No.3

R. J. SUNG. Mathcad program as a useful tool for the teaching and studying the sport biomechanics. Korean Journal of Sport Biomechanics, Vol. 14, No. 3, pp. 301-311, 2004. The purpose of this study was to verify the usefulness of the Mathcad program as a tool for the studying and teaching the sport biomechanics. A projectile motion was analyzed because it is the one of the most popular motion in sports activities. A 3 dimensional CG data for the high jump bar clear phase was used to calculate the initial velocity vector of the CG. Linear regression function and other functions such as cubic spline and derivative of Mathcad were used to calculate this vector. Finally, the approach angle to the bar and peak jump height was calculated. Programming in Mathcad was relatively easy compare to traditional computer language such as Fortran and C, because of the unique documentation method of Mathcad. Additionally the 2 and 3 dimensional graph function was very easy and useful to describe the mechanical data. If the use of Mathcad program is more popular in the field of sport biomechanics, it could greatly contribute to overcome the limit of research caused by the lack of proper programming ability.