고등학교 역도 우수선수와 비 우수선수간 인상동작의 운동학적 비교

유재광(Jae Kwang Ryu),김창범(Chang Bum Kim) 한국사회체육학회 2001 한국사회체육학회지 Vol.16 No.-

This study is a kinematic comparison of weight lifting snatch movements of three excellent players and non-excellent players currently attending C Athletic High School. A three-dimensional image nalysis of their lifting movements shows the following results. 1. The time required for lifting recorded the shortest at the top pull in both of the groups. This result indicates that the excellent players finished the second pull within a shorter period of time. On the other hand, the non-excellent players did not fully lift up the barbell and they started the drop movement too soon. This resulted in an unstable body control from the drop movement to lock out. 2. Both the groups recorded the highest wrist velocity at the second pull. In the excellent players the acceleration velocity marked the highest at the top pull, and this means that they effectively performed the vertical lifting movement by a fast stretch of wrist at the second pull and also at the highest reaching point of the barbell. 3. In both of the groups, both the velocity and acceleration of elbow and shoulder recorded the highest when the barbell reached the highest point at the second pull. This result indicates that the non-excellent players lifted the barbell vertically by the stretch of elbow joint and the upper body only, and this deterred the increasing of barbell velocity. 4. The changes in the knee joint angle showed a mountaintop-like curve in both the groups. Some hollowed points were noticed since they used a secondary knee-bending skill. The hip joint angle showed a significant change at the top pull in the excellent players only. This result indicates that the non-excellent players did not make the most of their strong leg power. 5. Both the groups recorded the highest angular velocities of the knee and the hip joint at the first and the second pull which require a power momentum. The excellent players maintained a faster angular velocity. In addiction, the angular velocities of the knee and the hip joint changed significantly at the very moment of lifting in the excellent players. On the other hand, the non-excellent players lifted the barbell in a squat stance.

도시철도 소음저감시스템 시공기술 개발

유재광(Jae-Kwang Ryu),민준호(Jun-Ho Min),김효산(Hyo-San Kim),이달재(Dal-Jae Lee) 한국철도학회 2011 한국철도학회 학술발표대회논문집 Vol.2011 No.10

Recently the number of passengers using urban railway has been increased by reasons of the reductions of car use due to high fuel prices and the enlightenment about the environment. Above all the noise and the vibration coming from the friction between the wheel and the rail of trains in operation which is not only a factor that hinders riding comforts but causes civil complaints. Furthermore the noise has become social issues from tightening the relevant regulations by the government since January 2010. Although ballasted tracks were constructed on urban railways at the time of opening they have been changed into slab tracks because slab tracks require much less maintenance. However in view of sound absorptivity of track slab tracks have 10 times less capability than ballasted tracks(ballasted track : 0.5~0.6 / slab tracks : 0.06) results more noise than that of ballasted tracks as much as 3dB(A) since slab tracks emit more reflection noise. Therefore in order to minimize reflection noise on slab tracks noise abatement system has been developed as a national R&D program to apply on-site test. It is assumed that the construction technology developed in this study can be used not only as basic data for the on-site test for the noise reduction in urban railway but as an efficient construction method.

궤도변위계측을 통한 신축이음장치 상태 적정성 평가

유재광(Jae Kwang Ryu),민준호(Jun Ho Min),김효산(Hyo San Kim),최진유(Jin Yoo Choi),박용걸(Yong Gul Park) 한국철도학회 2012 한국철도학회 학술발표대회논문집 Vol.2012 No.10

열차의 주행안전성 확보 및 승차감 향상을 위하여 레일의 장대화가 추진되고 있다. 장대레일을 설치함에 있어 이론적으로는 무한대로 설치할 수 있지만 온도변화에 의한 레일의 축방향력, 열차주행에 의한 복진 현상, 교량구조물과의 간섭 등 현장여건 등을 고려하여 일정 구간마다 신축이음장치를 설치하여 신축을 조절하도록 하고 있다. 본 연구는 서울메트로 1~4호선에 부설되어 있는 신축이음장치에 대한 현장조사와 궤도변위계측을 통한 분석으로 신축이음장치 상태 적정성 평가를 통하여 궤도유지보수의 효율성을 높이고 열차 주행안전성 확보 및 승차감 향상을 도모하고자 한다. The Continuous Welded Rail has been driven forward for an improved driving safety and ride quality of train. The Continuous Welded Rail can be installed in theory without limit, but it is in reality adjusted with an expansion joint being installed at a certain section by considering the project factors like an axial force of rail under a temperature change, Creepage State driven by a running train and an intervention of bridge structures. This study is to have an appropriate test of the status of the expansion joint of Continuous Welded Rail installed at 410 places at Line No.1~4, Seoul metro through a field investigation and track displacement measurement analysis, leading to increase the efficiency of a track-maintenance repair and to have an improved driving safety and riding comfort of train.

도시철도 콘크리트궤도의 유형별 초기시설 투입비용 분석

김효산(Hyo-San Kim),유재광(Jae-Kwang Ryu),민준호(Jun-Ho Min),한동은(Dong-Un Han),이달재(Dal-Jae Lee) 한국철도학회 2011 한국철도학회 학술발표대회논문집 Vol.2011 No.10

The total length of Korean urban railways reaches 1,200km. Urban railway used to be installed with ballasted tracks by reason of low cost at the time of construction slab tracks are now being installed due to the reasons of the improvement in safety lengthening service life and more economical method in terms of maintenance. The length rate of slab tracks has exceeded 70% of the domestic urban railways with the methods ranging from STEDEF LVT ALT Eidan-type B2S to RHEDA. This study surveyed the share of domestic slab tracks and compared and evaluated the input cost at the initial stage by the types of slab tracks. Construction processes have been standardized by the existing design documents and calculated the initial input cost for the length of 1km of a hypothetical straight line. Cost breakdown structure was evaluated as materials cost construction cost equipment cost indirect cost etc. It is expected that this study will be used in selection & evaluation which is considering the economic feasibility of slab tracks.

여자대학생 역도 인상동작의 운동학적 분석

김창범(Chang Bum Kim),유재광(Jae Kwang Ryu) 한국사회체육학회 2002 한국사회체육학회지 Vol.18 No.2

This research got following conclusion as result that analyze impression action kinematically to 3C university woman weight lifters who are situated in Chungchong-bukdo : 1. The time was average 2.71 seconds that is faster 0.05 seconds than country representative woman player. the step which the action is achieved fastest appeared to the first pull after start. 2. Vertical displacement of Barbell shows action form that waste force more than necessity and pull Barbell because all subjects appear more than height provision 80%. 3. While angle of knee joint enforces second pull, subject-1 and subject-2 much changes of 46.5°, 44.2° while appear subject-3 change that is less of 22.9°s appear. 4. While enforce second pull, change of hip joint angle expressed high fluxion by average 69.2° in this research while country representative woman player shows 45.8° change.

도시철도의 터널구간에 부설된 레일신축이음매장치 상태 평가

김효산(Hyo-San Kim),민준호(Jun-Ho Min),유재광(Jae-Kwang Ryu),정명렬(Myung-Ryule Jung) 한국철도학회 2012 한국철도학회 학술발표대회논문집 Vol.2012 No.10

우리나라의 도시철도에 부설된 신축이음매장치는 692개소로서 초창기 지하철건 현장에 주로 부설되어 있다. 현재는 초기투입비용이 다소 높더라도 안전도 향상과 사용수명이 길고 유지관리 측면에서 경제성이 있는 콘크리트궤도로 건설되고 있기 때문에 특수한 경우를 제외하고는 신축이음매장치를 부설하지 않는다. 지하철 초창기에 건설된 서울지하철 1~4호선에서는 레일신축이음매장치가 410조나 부설되어 있다. 본 연구는 서울지하철 1~4호선에 부설되어 있는 장대레일의 신축이음매장치에 대한 현장 정밀조사, 횡압 및 도상저항력 등 궤도계측을 통한 분석으로 터널구간에 부설된 레일신축이음매장치의 상태를 평가할 수 있는 방법을 도출하였다. 이를 통해 궤도유지보수의 효율성을 높이고 비용을 절감함으로서 운영기관의 경영개선에 기여할 것으로 여겨진다. 692 sets of rail expansion joints have been used in Dorean urban railway wahich were mostly installed in early opened railway lines. Even though it takes high initial investment cost, concrete slab tracks have been installing because it provides better safety, longer lifespan and cost effective so we no longer install rail expansion joints on new lines except for special cases. There installed 410 sets of rail expansion joints on Seoul Metro, Seoul subway lines 1-4. In this study, we draw a method to decide whether to use them or not the existing rail expansion joints by analyzing detailed site survey and track measurement data such as track lateral force and ballast resistance force of rail expansion joints installed between continuous welded rails on Seoul subway lines 1-4. We consider that this study will contribute in improving management for railway operators by raising track maintenance efficiency and lowering cost.

장대레일 신축이음매 재설정에 관한 연구

민준호(Jun-Ho Min),이창헌(Chang-Hun Lee),유재광(Jae-Kwang Ryu),김효산(Hyo-San Kim) 한국철도학회 2011 한국철도학회 학술발표대회논문집 Vol.2011 No.10

This research increases efficiency of track-maintenance repair and cuts maintenance cost with relocating Continuous Welded Rail how to set up install criteria by comprehension analysis through an on-the-spot survey and track measurement about installing place at expansion joint of Continuous Welded Rail. This scope of this research is 427 places installed at Line No.1~4 Seoulmetro. We take a field study and select two spots. So we survey wheel-load cross-load and railbed cross-resistance and suggest install criteria of expansion joint of Continuous Welded Rail through investigation and analysis of track facilities about neighboring section of expansion joint.

B2S궤도시스템의 초기 시설 투입비용 분석 (Initial Investment Cost Analysis of Facilities of B2S Track System)

김효산(Hyo-San Kim),민준호(Jun-Ho Min),유재광(Jae-Kwang Ryu),이달재(Dal-Jae Lee) 한국철도학회 2011 한국철도학회 학술발표대회논문집 Vol.2011 No.5

B2S(Ballasted track To Slab track) that is track system has been first developed in 2004 with foundation of rich experience and know-how of subway track upkeep and mending of facilities in 36 years to improve an existence pebble track at a concrete track. ‘B2S’ is admitted technology through patent registration in the domestic and Europe and it’s made by a factory and put together at field, so it’s able to construct precisely and to reduce a construction period. In addition, safety, the ecological balance and durability are excellent, and walking, cleaning, etc. has the advantage of easy maintenance. ‘B2S’ is currently laying 27.7㎞ at Seoulmetro as of end of 2010 standard, but it’ll be expected to be applied to a domestic Metro more from now on. It is possible to classify the total cost resolution structure of B2S system by R&D cost, test production and experiment cost, the initial facility cost, maintenance cost, disposal cost. In this research, it seems useful for selection evaluation which considered the life cycle cost or economics of the concrete track structure by analyzing an initial cost of facilities.

도시철도 영업운행선의 궤도개량공사 서행구간 속도향상 연구

김효산(Hyo-San Kim),이창헌(Chang-Hen Lee),유재광(Jae-Kwang Ryu),정명렬(Myung-Ryule Jung) 한국철도학회 2012 한국철도학회 학술발표대회논문집 Vol.2012 No.10

도시철도의 영업 운행선에서 기존 자갈궤도를 콘크리트궤도로 개량하면서 궤도 가받침 상태에서의 열차안전운행과 타설된 콘크리트의 품질확보를 위하여 영업열차가 출퇴근시간대에는 40km/h, 평상시는 30km/h로 서행운전하고 있다. 출근시간대의 운전시격은 2.5분으로 열차 정시운행 확보가 어려워 지연운행에 따른 민원이 발생하고 있다. 본 연구는 궤도개량공사로 인한 서행구간의 속도를 향상하기 위하여 기존 자갈궤도를 철거하고 콘크리트궤도를 지지 및 궤광을 고정해 주는 궤도 가받침 시설에 대한 안정성을 평가하였다. 또한 열차운행 속도별 가받침 부재의 구조해석을 통해 열차속도의 증속모델을 시뮬레이션하여 이에 대한 가받침 시설의 개량요소를 도출하였다. During the condition of temporary track support system which is installed when replacing existing ballast tracks to concrete slab tracks on operating line of urban railway, slow train speed shall be applied in order to secure the safe train operation and the quality assurance of poured concrete by restricting train speed as 40km/h for peak hours and 30km/h for non-peak hours. There have been frequent complaints from passengers due to difficulty to satisfy the train headway of 2.5 minutes during morning peak hours. In this study, the safety of temporary track support system has been evaluated which is used during track improvement work to speed up for the section with slow speed and to support track track frame after removal of existing ballast track. And, the improvement method for temporary track support system has been studied by simulating speedup model of train speed through structural analysis for support material based on applying different train speeds.

여자중학생 배드민턴 스매시 동작의 운동학적 분석

김창범(Chang Bum Kim),박종진(Jong Jin Park),유재광(Jae Kwang Ryu) 한국사회체육학회 2002 한국사회체육학회지 Vol.18 No.2

This research got following conclusion as result that analyze smashing action through third dimension reflex analysis kinematically to 4 C girls` junior high school badminton players who are situated in Chungchong-bukdo. 1. All subjects expressed the fast velocity at back swing steps doing not become enough shoulder turning and bends of elbow except subject S1. 2. The velocity of wrist and racket head was expose that subject S2 heightens the velocity of shuttle cock and increase momentum using more snap shot of wrist more than other subjects seeing the fastest velocity. 3. Shoulder and elbow angle change were caused by softness of each joint because the students in growth period made bigger angle change than adult. 4. Angle of wrist was exposed that do not use wrist snap shot because all subjects are bent already as they impact and consisted stroke point in their backward of head except subject S2. 5. Angle change of hip joint displayed swing that do on upper body and arm without using strong waist force appearing as all subjects are small more remarkably than virtue research result. 6. In general, Form of smashing action is lacking exercise career yet on the whole and was expose that cooperation action of each joint drops remarkably as a student in growth period.