• 한국과학교육학회지
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• 제33권1호
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• pp.193-207
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• 2013

이 연구는 지구와 달 표면에서 물체의 운동에 대한일반 중학생들과 과학영재학생들의 개념을 조사하였다. 연구 대상은 일반 중학교 중학생 1학년 61명, 2학년 51명, 3학년 51명 총 163명과 대학부속 과학영재교육원 중등 과학영재학생 32명으로 하였다. 연구 내용은 지구와 달 표면에서 연직, 경사면, 수평면에 따른 물체의 운동에 대한 개념으로 하였다. 각각 지구와 달 표면에서 크기는 같고 질량이 다른 두 물체를 동시에 놓거나, 같은 속력으로 위쪽으로 던지거나, 수평면에서 굴렸을 때 '어느 것이 먼저 도착하는가?'를 조사하였다. 지구와 달 동시 상황에서는 같은 물체를 지구와 달 표면에서 동시에 놓거나, 던지거나, 굴렸을 때 '어느 장소에 먼저 도착하는가?'를 조사하였다. 연구결과 과학영재학생들이 일반 중학생들 보다 지구 표면에서 연직, 경사면, 수평면의 모든 조건에서 물체의 운동에 대한 개념에 유의미한 차이가 있었고, 달 표면에서 연직 위 방향에서 물체의 운동에 대한 개념에 유의미한 차이가 있었다. 지구와 달 표면 동시 상황에서는 연직 아래 방향에서 물체의 운동에 대한 개념에 유의미한 차이는 없었고, 연직 위 방향, 경사면, 수평면에서 물체의 운동에 대한 개념에 유의미한 차이가 있었다. 연구 결과를 통해서 얻은 결론은 첫째, 지구와 달 표면에서 물체의 운동에 대한 설명을 할 때 진공에 대한 의미와 중력의 크기에 대한 학습이 먼저 이루어져야 한다. 둘째, 중학생들에게 다양한 상황과 조건에서 물체의 운동을 통합적으로 이해하도록 지도해야한다. 셋째, 중학생들은 상황을'동일시'하려는 사고 경향이 있다. 마지막으로 힘과 물체의 운동은 물리 영역에서 매우 중요한 단원이며, 교사가 물체의 운동을 설명할 때 위 결과들을 유념해서 가르쳐야 한다.

• 대한인간공학회지
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• 제26권1호
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• pp.47-53
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• 2007

The uncanny valley is a hypothesis about robotics concerning the emotional response of humans to robots and other non-human entities. Although it stands today as one of the robots and synthetic characters, the uncanny valley was speculative and few studies have been performed to test the theory. In two experiments, a total of 183 participants were employed to explore this hypothesis. The results of experiment 1 indicate that the perceived human likeness of a robot is not a key factor causing uncanny valley. And the results of experiments 2 suggest that even if the appearance and motion of a robot become fully human, the emotional response of humans could not reach human-human empathy levels.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.990-994
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• 2004

This paper presents a method to predict the transient characteristic of the air lubricated slider head in a hard disk drive by using optimization technique. The time dependent modified Reynolds equation based on the molecular slip flow approximation equations was used to describe the fluid flow within the air bearing and the implicit finite difference scheme is applied to calculate the pressure distribution under the slider head. The exhaustive search combined with the Broyden-Fletcher-Goldfarb-Shanno method were employed to obtain optimum design variables which are taper angle, rail width and taper length in order to keep the forces and moments acting on the slider head in dynamic equilibrium. The results show that the optimal head slider of the magnetic head has good stability characteristic that can reach the steady state within 0.5 microsecond.

• 한국정밀공학회지
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• 제33권7호
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• pp.601-606
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• 2016

In this paper, an energy harvester is developed that has advantages regarding piezoelectric noise minimization, mass production, and an easily available environmental energy source, electromagnetic induction, as well as low-frequency bandwidth and high amplitude. A process for fabricating a three-dimensional multilayered planar coil using micro-electro-mechanical systems (MEMS) on a flexible printed circuit board FPCB is introduced. Optimal shape and size were calculated via internal resistance and inductance, and a prototype was fabricated through the MEMS procedure while considering the possibility of mass production. Although the internal resistance matched the designed value, the electromotive force generated did not reach the intended amount. The main reason for the decrease in efficiency was the low area of coil outskirt exposed to the magnetic field while there was relative motion between the magnet and the coil.

• 한국정밀공학회지
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• 제28권2호
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• pp.211-218
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• 2011

We reported the design, prototype, test drive, and mechanical & electrical engineering analyses of a power-lifting wheelchair using mecanum wheels. Mecanum wheels enable translational and rotational movement of the device in any direction on the ground. The power-lifting capability enables the seated individual to reach the standing height of a non-disabled individual. This mecanum wheelchair is fully controlled by the joystick attached to the armrest. The motion of the wheelchair and lifting action of the seat were studied using statics and dynamics. We believe this mecanum wheelchair is a prime candidate for commercial production.

• 제어로봇시스템학회논문지
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• 제13권7호
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• pp.624-630
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• 2007

The dynamic window approach(DWA) is a well known technique for reactive collision avoidance. It shows safe and efficient performance in real-world experiments. However, a robot can get stuck in local minima because no information about the connectivity of the free space is used to determine the motion. The global DWA can solve this problem of local minima by adding a navigation function. Even with the global DWA, it is still difficult for a robot to execute an abrupt change in its direction, for example, entering from the corridor to a doorway. This paper proposes a modified global DWA using the included angles of waypoints extracted from an optimal path. This scheme enables the robot to decelerate in advance before turning into the doorway. Therefore the robot can reach the goal position more safely and efficiently at high speeds.

• 대한견주관절학회:학술대회논문집
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• 대한견주관절학회 2009년도 제17차 학술대회
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• pp.220-220
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• 2009

In fencing, athletes must hit opponents by the sword of fencing, so they need long reach between their foot and their tip of the sword. We thought the motion of shoulder joint, mainly scapula, is one of the important roles in this action and noticed the difference of right and left side in muscles around scapula caused by this action. We evaluated these muscles with MRI imaging in 5 high-level athletes of fencing who aims at the next Olympics (3 men and 2 women, their average age is 21 years). Besides we observed their physical measurement related with these muscles. We reported the characteristics of these results.

• 한국컴퓨터정보학회논문지
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• 제10권1호
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• pp.149-156
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• 2005

전파를 이용한 통신이 활성화 되어 인터넷상의 네트워크에 연결하여 다양한 서비스가 제공되고 있는 현실에서 통신 서비스의 질을 높이기 위한 물체의 특징 점 탐지 및 추적의 중요성이 크게 대두되었다. 본 논문은 전파가 미치지 않는 음영 공간의 탐지와 추적을 위한 연구의 내용으로, Snakes 알고리즘을 이용하여 음영 공간을 탐지하고, 탐지된 음영 공간 내에서 어느 한 출발 지점에서 목표 지점까지의 경로를 추적하는 시스템의 기반을 제시하고자 하였다.

• 천문학논총
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• 제14권2호
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• pp.69-78
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• 1999

We present the results of one-dimensional numerical simulations of SNR evolution in the in­homogeneous medium considering the effects of the evaporation of the cloud and the thermal conduction. We have included the effects of changing evaporation rate as a function of cloud size and the ambient temperature so that the clouds could be evaporated completely before they reach the center of the SNR. The heat conduction markedly changes the density distribution in the remnant interior. To explain the observed morphologies of the centrally peaked X-ray SNRs(for example W44), the maximal thermal conduction is required. However, this is unlikely due to the magnetic field and the turbulent motion. The effects of the evaporation of the cloud and the thermal conduction described here may explain the class of remnants observed to have centrally peaked X-ray emmision.

• Bulletin of the Korean Chemical Society
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• 제19권6호
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• pp.634-641
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• 1998

Quasiclassical trajectory calculations were carried out for the reactions of $H+H_2$ (V=O, J=O) and its isotope variants on the Siegbahn-Liu-Truhlar-Horowitz potential energy surface for the relative energies E between 6 and 150 kcal/mol. The goal of the work was to understand the inter- and intramolecular isotope effects. We examine the relative motion of reactants during the collision using the method of analysis that monitors the intermolecular properties (internuclear distances, geometry of reactants, and final product). As in other works, we find that the heavier the incoming atom is, the greater the reaction cross section is at the same collision energy. Using the method of analysis we prove that the intermolecular isotope effect is contributed mainly by differences in reorientation due to the different reduced masses. We show that above E=30 kcal/mol recrossing also contributes to the intermolecular isotope effect. For the intramolecular isotope effect in the reactions of H+HD and T+HD, we reach the same conclusions as in the systems of $O(^3P)+HD$, F+HD, and Cl+HD. That is, the intramolecular isotope effect below E=150 kcal/mol is contributed by reorientation, recrossing, and knockout type reactions.