• 한국운동역학회지
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• 제15권3호
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• pp.21-30
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• 2005

The purpose of this study is helps to make full use for perfect performance by grasping the defects of Tichonkich motion performed by athlete CSM For this, the study analyzed kinematical variables through Tichonkich motions performed at the first selection competition(1st trial) and final selection competition(2nd trial) for the dispatch to the 28th Athens Olympic Games using the three-dimensional cinematographical method with a high-speed video camera, and obtained the following results. 1. During Tichonkich motion, the execution time of up swing and the right hand moving to the left bar was shorter in the 2nd trial than the 1st one, while the execution time of down swing, the support of the left bar and the right hand moving to the right bar was longer in the 2nd trial than the 1st trial. 2. The horizontal position of COG in the 2nd trial was -35cm in the 1st stage, 42cm in the 3rd stage and 29cm in the 4th stage, that is, it showed a great swing focused on the circular movement compared to the 1st trial, while the vertical position of COG was -59cm in the 2nd stage, that is, it showed a small swing focused on a up and down movement. Also the 5th stage vertical position was 98cm, and the 6th stage vertical position was 95cm in the 2nd trial which were higher than those of the 1st trial, so it has provided magnificence required in the modern gymnastics. 3. And it was indicated that the horizontal velocity at the down swing phase proceeded forward more rapidly in the 2nd trial than that in the 1st trial, and the reverse ascent made a rapid vertical rise lessening left and right velocity change. And in the 5th stage, the 2nd trial was kept very slower in horizontal, vertical and left and right velocity that in the 1st trial, so it reached a handstand with leisurely movement. 4. In the 2nd trial, shoulder joint of the 1st, 2nd, 3rd stages kept a larger angle than that in the 1st trial, that is, it made a great swing while in the 1st trial, it showed a swing movement dependent on kick movement by the flexion and extension of hip joint. Also in the 2nd trial, the body formed a vertical posture with both hands supporting the left bar and hip joint was kept larger as $198^{\circ}$ and $190^{\circ}$ in the 5th and 6th stage than that in the 1st trial, so it made a handstand with the body uprightly stretched out, and magnificent and stable movement.

• 대한토목학회논문집
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• 제7권2호
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• pp.141-153
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• 1987

고층 건물의 정확한 거동을 구하기 위한 구조 해석은 컴퓨터 적용의 중요한 분야로 취급되어 왔다. 본 논문에서는 건축구조물에 대한 3차원적인 해석방법을 연구하였다. 이 해석 방법은 건물을 각각의 독립된 프레임의 조합체로 보고 해석하므로 매우 효율적이며, 건물의 3차원적인 거동에 관한 고려는 건물이나 하중이 대칭이 아닐 때는 특히 중요하다. 그리고 matrix condensation 기법을 이용함으로써 컴퓨터의 용량과 해석 시간이 상당히 절약되므로 매우 경제적이다. 본 논문의 건물 구조해석 컴퓨터 프로그램 PFS의 정확성과 효율성을 증명하기 위해 여러가지 예제들에 대해서 SAPIV 에 의한 해석 결과와 비교하였다. 그러므로, 본 논문에서 제안한 해석방법은 고층 건물의 구조 설계에서 매우 효율적이라 할 수 있다.

• 제어로봇시스템학회논문지
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• 제17권7호
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• pp.685-696
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• 2011

An efficient laparoscope manipulator robot was designed to automatically control the position of laparoscope via a passive joint on end-effector position. The end position of the manipulator is controlled to have corresponding velocity defined in the global coordinate space using laparoscopic visual information. Desired spatial position of laparoscope was derived from detected positions of surgical instrument tips, then the clinical viewing plane was moved by visual servoing task. The laparoscope manipulator is advantageous for automatically maintaining clinically important views in the laparoscopic image without any additional operator. A laparoscope is mounted to a holder which is linked to four degree of freedom manipulator via universal joint-type passive rings connection. No change in the design of laparoscope or manipulator is necessary for its application to surgery assistant robot system. Expanded working space and surgical efficiency were accomplished by implementing slant linking structure between laparoscope and manipulator. To ensure reliable positioning accuracy and controllability, the motion of laparoscope in an abdominal space through trocar was inspected using geometrical analysis. A designed laparoscope manipulating robot system can be easily set up and controlled in an operation room since it has a few subsidiary devices such as a laparoscope light source regulator, a control PC, and a power supply.

• Applied Microscopy
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• 제39권2호
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• pp.175-183
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• 2009

이 논문에서 50 pm 이하의 원자열 분해상을 효과적으로 보여 주는 결정 밑 표면 파동함수(EPW)의 음(-)의 2차 도함수의 시뮬레이션 영상들이 나타나 있다. 그리고 해당 EPW는 HRTEM에서 일련의 비 초점 단계의 관찰 영상으로부터 얻을 수 있다. 이 논문에 나타난 시뮬레이션한 영상들은 대체로 50 pm 이하의 원자열 간격을 주는 Si과 InAs의 [114] 및 [116] 방위 축에 대한 것이다. 이 방법의 정당성에 대한 이론적 이유가 운동학적 회절이론을 기초로 한 분석에서 주어졌다. 그리고 그 응용성의 한계도 논의되었다.

• 한국운동역학회지
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• 제13권3호
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• pp.15-26
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• 2003

This study was conducted to investigate the performance times, CM position and CM speed, pole chord length and pole chord angle, whole body angular momentum(X axis), and grip width in pole vault event according to the event and phase; touch down, pole plant, take-off, maximum pole bending pole straight, pole release, peak height, and foot contact, pole contact, free flight. The pole vaulting of four male elite vaulters including six trial were filmed using two video digital cameras at 60 Hz at 56th national athletic match, and data were collected through the DLT method of three dimensional cinematography. In general the better jumper is, the longer the performance time is. And the greater CM speed is, and the better his transformation ability of CM horizontal speed into vertical speed is. As he uses a longer pole, his grip is higher, and it is a enough for him to rock back his body, so that he pulls and pushes the pole well keeping his hips close to. An greater maximum angular momentum and early positioning of the hips parallel to the bar makes his body far side of the bar and his bar clearance easier. Specially our national jumper needs to have more powerful braking force during foot contact phase, and take his body on the pole after maximum pole bending, and pull and push the pole strongly keeping his hips close to. Also he needs to have stronger muscular strength in order to control the longer pole and use the pole of proper tension more efficiently.

• Computers and Concrete
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• 제15권5호
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• pp.735-758
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• 2015

This work deals with unilateral effect of quasi-brittle materials, such as concrete. For this propose, a two-dimensional meso-scale model is presented. The material is considered as a three-phase material consisting of interface zone, matrix and inclusions - each constituent modeled by an appropriate constitutive model. The Representative Volume Element (RVE) consists of inclusions idealized as circular shapes randomly placed into the specimen. The interface zone is modeled by means of cohesive contact finite elements developed here in order to capture the effects of phase debonding and interface crack closure/opening. As an initial approximation, the inclusion is modeled as linear elastic as well as the matrix. Our main goal here is to show a computational homogenization-based approach as an alternative to complex macroscopic constitutive models for the mechanical behavior of the quasi-brittle materials using a finite element procedure within a purely kinematical multi-scale framework. A set of numerical examples, involving the microcracking processes, is provided. It illustrates the performance of the proposed model. In summary, the proposed homogenization-based model is found to be a suitable tool for the identification of macroscopic mechanical behavior of quasi-brittle materials dealing with unilateral effect.

• 한국운동역학회지
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• 제14권2호
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• pp.1-14
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• 2004

This study was intended to contribute to allowing athletes to raise a technical understanding of two motions of high difficulty such as the Swallow motion and the Nakayama motion and enhance their competitive power by analysing the kinematical factors required to link those two motions on the competitive scene on the rings for current national athletes. For this purpose, the game of the ring event was videotaped for male heavy gymnasts participating in the final elimination match of the 2004 Athens Olympic Games. This study attempted to select the performing motions of the final 1st-and 2nd-place athletes performing the linking motions from the Swallow motion and the Nakayama motion using the DLT(direct linear transformation) method. As a result, it arrived at the following conclusion : A1 properly performed the flexing and extending movements using the angular velocity of the segment and joint as the switching motion using the body at the time of linking the motion from the Swallow skill to the Nakayama skill. A2 was evaluated to perform the skill taking the form of depending on the force at the static state. Therefore, it is thought that A1 should take care of shaking at the time of using the elasticity of the body. It is thought that in case of A2 the proper use of the elasticity of the body take care of shaking at the switching motion while taking advantage of the force will contribute to his competitive power.

• 대한토목학회논문집
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• 제13권2호
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• pp.237-242
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• 1993

기초 지반이 몇개의 토층으로 구성된 경우 그 지지력은 각 토층의 강성도와 두께 및 위치 등에 의해 영향을 받는다. 따라서 기초 설계시에 기초의 지지력을 정확히 구하고 파괴면을 예측하기 위해서는 토층의 상태를 지지력 계산에 고려해야 한다. 본 연구에서는 기초 지반이 사질지반이고 중간에 상대적으로 조밀한 지층을 포함하는 경우에 조밀한 층의 두께나 위치가 기초의 지지력 및 파괴모양에 미치는 영향을 극한 해석의 상한한계(upper bound)쪽에서 완전해에 가까운 해를 구하는 K.E.M(Kinematical Element Method)을 이용하여 검토 하였으며, 기초 폭(B)의 3/5 B보다 깊지 않은곳에 조밀한 층이 위치하는 경우에는 기초의 지지력 과 파괴모양이 조밀한 층의 영향을 받는 것으로 나타났다.

• 한국정밀공학회지
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• 제22권11호
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• pp.82-90
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• 2005

Recently, the in-line vision inspection has become the subject of growing research area in the visual control systems and robotic intelligent fields that are required exact three-dimensional pose. The objective of this article is to study the pc based in line visual inspection with the hand-eye structure. This paper suggests three dimensional structured light measuring principle and design method of laser sensor header. The hand-eye laser sensor have been studied for a long time. However, it is very difficult to perform kinematical analysis between laser sensor and robot because the complicated mathematical process are needed for the real environments. In this problem, this paper will propose auto-calibration concept. The detail process of this methodology will be described. A new thinning algorithm and constrained hough transform method is also explained in this paper. Consequently, the developed in-line inspection module demonstrate the successful operation with hole, gap, width or V edge.

• 천문학회보
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• 제43권1호
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• pp.32.4-33
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• 2018

We study the kinematical properties of the Seyfert galaxy, NGC 4051 and Mrk 79. The data used in this study had been observed with OASIS spectrometer at CFHT 3.6m telescope using O300 grism, MR1. The wavelength coverage is $4760{\AA}$ $-5558{\AA}$, which includes emission lines, $H{\beta}4861{\AA}$, $[OIII]4959{\AA}$, and $[OIII]5007{\AA}$. We observe that forbidden lines have both narrow and broad components. Radial velocity of NGC 4051 is blue-shifted, perhaps due to the z value derived by the earlier studies, 0.002336. We use the revised z, 0.002099, according to the radial velocity of the central spectrum. NGC 4051 is face-on galaxy without rotation observed. Radial velocity of Mrk 79 shows a rotation characteristic in narrow components, relative to $PA=60^{\circ}$, red-shifted to north-west, and blue-shifted to south-east. In the [OIII] broad components, blue-shifted points are observed at the place at 2 arcsec apart from the center of Mrk 79 to north-west, which are likely to be gas outflow.