• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2008년도 공동학술대회
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• pp.141-144
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• 2008

선진국에서는 온실가스 감축을 위한 이산화탄소 지중저장에 대하여 다양한 연구가 진행되고 있으며, 또한 염수대수층을 대상으로 파일럿 사이트를 운영하고 있다. 이산화탄소 지중저장에 있어서 모니터링 기술로 탄성파 및 전기비저항 토모그래피탐사가 적용되고 있으며, 이산화탄소 주입 전후의 탄성파 및 전기비저항의 변화로부터 주입범위 및 거동 해석을 시도하고 있다. 본 연구는 이러한 모니터링 기술을 개발하기 위하여 고압베셀을 이용하여 압력 및 온도를 제어할 수 있는 실내모사 실험 장치를 개발하고, 다공질 사암에 초임계상태의 이산화탄소를 주입하면서 전기비저항 및 탄성파 속도를 측정할 수 있는 시스템을 구축했다.

• 과학교육연구지
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• 제45권3호
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• pp.326-335
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• 2021

본 연구에서는 무지개의 생성 원리를 분석할 수 있는 무지개 발생 장치를 개발하였다. 무지개는 물방울에 대한 빛의 분산 및 반사와 굴절에 의해 형성되지만, 물방울 한 개로만 무지개를 만들 수 없다. 따라서 본 연구에서는 여러 물방울들이 만드는 빛의 경로를 통해 무지개를 관측할 수 있는 장치를 만들어 무지개 생성 원리에 대해 학생들이 보다 쉽게 이해하도록 하였다. 물방울이 만드는 무지개는 유리구슬을 이용하여 재현하였고, 관찰자의 위치와 광원의 고도 등과 같은 무지개 생성과 관련된 다양한 변인을 변화시키며 무지개를 구현하였다.

• 전기학회논문지
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• 제57권11호
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• pp.2001-2005
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• 2008

This paper presents a design of a simulation apparatus to evaluate an operational control algorithm for the PRT system. PRT systems require very short headways to increase the line capacity and a very reliable vehicle control algorithm for avoidance of the impact between vehicles. Therefore, it can be said that the development of an reliable operational control algorithm for the PRT systems is much more important than that of the hardware configurations. In this paper an apparatus is proposed which is composed of virtual vehicles, a central control system, a man-machine interface and monitoring device, making it possible for the designed operational control algorithm to be implemented and tested. For the test of the proposed apparatus a test operational control algorithm is designed and the experimental results show the effectiveness of the proposed simulation apparatus for test and evaluation of the PRT operational control algorithms.

• Computers and Concrete
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• 제31권1호
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• pp.71-84
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• 2023

In this paper, the effects of the thickness of cubic samples on the tensile strength of concrete blocks were studied using experimental tests in the laboratory and numerical simulation by the particle flow code in three dimensions (PFC3D). Firstly, the physical concrete blocks with dimensions of 150 mm×190 mm (width×height) were prepared. Then, three specimens for each of seven different samples with various thicknesses were built in the laboratory. Simultaneously with the experimental tests, their numerical simulations were performed with PFC3D models. The widths, heights, and thicknesses of the numerical models were the same as those of the experimental samples. These samples were tested with a new tensile testing apparatus. The loading rate was kept at 1 kg/sec during the testing operation. Based on these analyses, it is concluded that when the thickness was less than 5 cm, the tensile strength decreased by increasing the sample thickness. On the other hand, the tensile strength was nearly constant when the sample thickness was raised to more than 5 cm (which can be regarded as a threshold limit for the specimens' thickness). The numerical outputs were similar to the experimental results, demonstrating the validity of the present analyses.

• 대한화학회지
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• 제46권3호
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• pp.252-264
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• 2002

이 연구는 끊는점과 녹는점에 관련된 실험 장치를 교육과정의 변화와 교과서의 유형에 따라 분석하고, 중등 과학교사들을 대상으로 이에 관련된 실험값과 교과서에 제시된 값이 다른 경우에 대한 인식을 조사하였다. 그리고 분별 증류, 온도계 보정의 실험 장치와 실 험 결과에 대한 인식도 조사하였다. 연구 결과, 교유고가정과 교과서의 종류에따라 끓는점과 녹는점에 관련된 실험 장치의 유형은 다양하게 변화되어 왔으며, 교사들의 인식도 전공과 근무 학교에 따라 다양하게 나타났다. 또한, 많은 교사들이 분별 증류 실험에서 실험값이 교과서에 제시된 값과 다른 원인을 교과서 내용의 잘못이나 실험 자체의 문제로 인식하고 있었다. 그리고 중학교에서 온도계 보정의 필요성에 대한 교사들의 인식은 다양하게 나타났는데, 화학을 전공한 교사들이 비화학 전공교사들보다 온도계 보정 필요성에 대한 인식이 더욱 높았다.

• Journal of Mechanical Science and Technology
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• 제19권5호
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• pp.1107-1115
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• 2005

In this study, a position and force simultaneous trajectory tracking control algorithm is proposed for a driving apparatus that consists of two pneumatic cylinders connected in series. The controller applied to the driving apparatus is composed of a non-interaction controller to compensate for interaction between cylinders and a disturbance observer aimed to reduce the effect of model discrepancy that cannot be compensated by the non-interaction controller. The effectiveness of the proposed control algorithm is proved by experimental results.

• Bulletin of the Korean Chemical Society
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• 제22권8호
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• pp.883-888
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• 2001

We describe an ion-surface scattering apparatus newly developed to investigate the reactive scattering process of low-energy alkali-metal ions at surfaces. The apparatus consists of an alkali-metal ion gun that is rotatable by 360°, a quadrupole mass spectrometer (QMS) with an ion energy analyzer, a sample manipulator with a heating-and-cooling stage, and an ultrahigh vacuum (UHV) chamber that houses these components. Preliminary experimental results obtained from the apparatus are presented on angular and energy distributions of the ions scattered from clean Pt(111) and water-adsorbed Pt surfaces.

• 대한가정학회지
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• 제26권2호
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• pp.69-79
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• 1988

This study was to increase the experimental learning effect of textile materials in middle and high school. To this study, three kinds of simply devised apparatus were used for warmth retaining test, air permeability test and static electricity test. Two classes were chosen in a girls' high school comparing learning effect and classified the theoretical learning group and the experimental learning group. In the experimental group, a teaching plan to teach the properties of textile materials was made to use these apparatuses. The results were. 1. In the interest on the unit either the theoretical learning group or the experimental learning group were not different significantly. 2. In the items facilitation of motivation, unsatisfied desires and prevention of failure, effect of transfer and development of inquiry power, both groups were significant. 3. For the purpose of comparing the learning effect, two groups were examined for determining the level of understanding after teaching properties of textile materials. The mean value of the experimental learning group was higher than that of the theoretical learning group. The experimental learning group had more higher markers(over the point of 90) than the theoretical learning group.

• 동력기계공학회지
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• 제10권3호
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• pp.97-103
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• 2006

In this study, a position trajectory tracking control algorithm is proposed for a pneumatic artificial muscle driving apparatus composed of a actuator which imitates the muscle of human, a position sensor and a control valve. The controller applied to the driving apparatus is composed of a state feedback controller and disturbance observer. The feedback controller which feeds back position, velocity and acceleration is derived from the linear model of pneumatic artificial muscle driving apparatus. The disturbance observer is designed to improve trajectory tracking performance and to reduce the effect of model discrepancy. The effectiveness of the designed controller is proved by experiments and the experimental results show that the pneumatic artificial muscle driving apparatus with the proposed control algorithm tracks given position reference inputs accurately.

• 한국정밀공학회지
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• 제22권2호
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• pp.60-69
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• 2005

In electrostatic suspension system of thin plates like a silicon wafer or an aluminum disk for hard disk applications, the lateral restoring force exerted on a suspended object plays an important role since the lateral motion of the suspended object, owing to the inherently stable restoring forces, can be passively stabilized without any active control of it. This paper reports about the measurement apparatus of the lateral restoring force originating from a relative translation of the suspended object with respect to the electrodes-for-suspension. An approximate calculation of the lateral force in disk-shaped objects, the structure of the measurement apparatus, a measurement method, stabilization condition and the guideline in designing the measurement apparatus are described. Experimental results obtained by using a 3.5-inch aluminum disk as a suspended object are presented as well in order to assess the magnitude of lateral force and stiffness, and also verify the usefulness of the measurement apparatus.