• 대한화학회지
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• 제64권6호
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• pp.379-388
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• 2020

본 연구에서는 초등학생의 실험기구 교육을 위한 TEP 활동(Trigger interest; 흥미 유발-Explore experimental apparatus; 실험기구 탐색-Practice experimental apparatus; 실천적 사용)을 개발하고 이를 적용하여 그 효과를 알아보았다. 과학을 처음 접하는 초등학교 3학년을 대상으로 교과서에 제시되어있는 실험기구 중 4가지(비커, 전자저울, 유리막대, 약숟가락)를 선별하여 연구를 진행하였다. 그 결과 TEP 활동을 통해 단편적인 사용법이나 주의사항만을 알고 있던 학생들이 실험기구의 생김새에 따른 특징과 연관 지어 실험기구에 대한 설명을 할 수 있게 되었다. 또한 실제로 사용해보는 활동을 통해 실험기구 사용 능력이 향상되었다. 평소 과학 수업에서의 모습을 관찰한 결과 실험기구에 대해 학습한 내용을 떠올리며 적절하게 사용하려는 학생들이 많아졌으며 반복적인 활동을 통해 그 수가 증가함을 알 수 있었다. 초등학교에서 처음 배우게 되는 실험기구에 대한 지식적 이해와 사용 능력은 초, 중, 고등학교를 지나 실험이 주로 이루어지게 되는 대학교까지 영향을 미친다. 잘못된 용도와 사용법으로 실험을 하게 된다면 실험 결과의 신뢰도가 떨어질 뿐만 아니라 안전사고의 확률 또한 높아진다. 이러한 관점에서 본 연구를 통해 실험기구에 대한 교육을 초등 과학 교육과정에서 더욱 중요하게 다루어져야 하며 실제 교육을 해야 하는 교사들을 위해 다양한 교육 자료나 교수법이 개발되어야 함을 확인할 수 있었다.

• 한국가시화정보학회지
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• 제4권2호
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• pp.37-43
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• 2006

An experimental apparatus for PIV performance evaluation has been developed. Stardard uncertainty of a two-dimensional cross-correlation PIV system was investigated based upon the standard experimental apparatus, which was devised to model the rigid body rotating flows. For the systematic analysis of the uncertainty introduced by each component (algorithm, CCD camera, frame grabber) of the PIV system, standard images are fed into the component independently. The standard experiments show that 53% of the uncertainty in the present PIV system results from the frame grabber but the errors from the algorithm and digital camera are ignorable.

• 공학교육연구
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• 제23권3호
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• pp.32-40
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• 2020

A new moment of inertia experiment apparatus different from the existing one has been developed, which does not require deformation of a sample in order to fix it to the apparatus. This new experiment apparatus was able to experiment with constant-shaped objects that did not deform the samples, so that it enabled them for conducting an experiment which is close to an ideal rigid model dealt in the general physics course. The new experimental apparatus was easy and accurate in measuring the physical quantity by using the experimental principle of physical pendulum. In the results of the measurement of the moments of inertia of the six samples, all measurements were made to be accurate enough to measure with very small errors within 1%. In addition, it has been found to be useful as an experiment apparatus to understand the concept of the moment of inertia and to prove the formula for moment of inertia. Therefore, if the new moment of inertia experiment apparatus developed in this study is used in students' experiments, it is expected that students will be able to greatly increase their understanding of the concept of moment of inertia.

• 한국초전도ㆍ저온공학회논문지
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• 제4권1호
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• pp.135-139
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• 2002

In this study, the experimental open-tube and close-tube thermoacoustic apparatuses were built. In order to determine the optimum length of resonant tube and the optimum length of stack, the resonant characteristics of thermoacoustic apparatuses were investigated, The length of resonant tube varies from 400mm to 850mm. The experimental frequency varies from 100Hz to 1000Hz. In case of the second and third harmonics, the maximum temperature difference of open-tube thermoacoustic apparatus is 53$^{\circ}C$ (resonator length: 400mm) and the maximum temperature difference of closed-tube thermoacoustic apparatus is 51$^{\circ}C$ (resonator length: 500mm). In the open-tube thermoacoustic apparatus, the peak efficiency point is about 2%, 55%, 69% in the resonant tube and in the closed-tube thermoacoustic apparatus, the peak efficiency point is about 2%, 41%, 50% in the resonant tube.

• 한국초등과학교육학회지:초등과학교육
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• 제26권2호
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• pp.161-170
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• 2007

This study aims at helping us improve the methods used to teach elementary school students how to handle experimental apparatus by examining their manual skills and their understanding of the alcohol lamp, spuit and thermometer. To evaluate their ability to handle each experimental apparatus, a practical skills test and knowledge evaluation sheets were developed. The evaluation was carried out with 270 students from 2 classes each in the 3rd, 4th, 5th and 6th grade of D Elementary School located in Daejeon City. For their handling ability of the alcohol lamp, the results for the practical skills test showed that the students had a very low ability in placing objects in the center of the apparatus for safe use and also in adjusting the height of the trivet to place objects so that they contact the outer flames correctly. For the spuit, the pass rate of the skills test was generally low in regards to how students should grasp a spuit and the timing and method of depressing the rubber part before dipping it into liquid. For the thermometer, on the other hand, the pass rate was relatively high in every respect. The knowledge evaluation results for the use of experimental apparatus showed a very high rate of correct answers for alcohol lamps and thermometers. The test results for spoils also produced a relatively high rate of correct answers, with the exception of the test item regarding the way that students should grasp them.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.131-134
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• 1991

In order to determine an operating pattern of SLIM in an experimental MAGLEV vehicle, operating characteristics of SLIM are obtained using a disk type test facility. The test results are compared with the pre-estimated values. It is found that a closed loop control is required for operating at a constant slip-frequency condition which makes the normal force minimum.

• 대한화학회지
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• 제17권3호
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• pp.198-206
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• 1973

이형제와 유리분말의 혼합물을 회전시킬 수 있는 원형전기로 장치(장치 1), 유리분말을 자유낙하 시킬 수 있는 관형 전기로 장치 (장치 2) 및 유리분말을 propane gas의 화염과 함께 분사시킬수 있는 관형장치 (장치 3)를 사용하여 glass beads를 제조하였다. 사용한 기재는 한국산 sodium silicates glass 1,2, boro silicates glass 및 lead silicates glass 이며 cullet의 크기는 60mesh-300mesh이다. P.G.를 기재로 하여 이들 장치에 의하여 glass beads를 제조할 경우, 장치 1의 최적온도는 880$^{\circ}C$이고 장치 2의 최적온도는 980$^{\circ}C$이며 장치 3의 최적온도는 1100$^{\circ}C$이었다. 그렇지만 처리시간과 응착률 등으로 보아 장치 3의 방법이 가장 효율적이었다.

• 대한기계학회논문집A
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• 제28권9호
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• pp.1415-1421
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• 2004

In this study, a position synchronous control algorithm applied to two-axes pneumatic cylinder driving apparatus is proposed. The position synchronous control algorithm is composed of position controller and synchronous controller. The position controller is designed to minimize the effect of several nonlinear characteristics peculiar to the pneumatic cylinder driving apparatus on position control performance. The synchronous controller is designed to reduce the synchronous error. The effectiveness of the proposed control algorithm is proved by experimental results.

• 오토저널
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• 제9권4호
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• pp.41-49
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• 1987

It is an experimental study to improve the characteristics of combustion and exhaust emission gas in the gasoline engine. These characteristics are influenced by the fuel droplet size. To improve these characteristics, we make the ultrasonic atomization apparatus, and compare with the commercial carburetor. The results obtained are as follows: 1. Maximum atomization quantity is obtained by the vibrator of resonancy frequency 1.65MHz in the ultrasonic atomization apparatus. 2. With ultrasonic atomization apparatus, more than 99% of atomization rate can be obtained regardless of intake air temperature, velocity, and air-fuel ratio. 3. Atomization rate of the commercial carburetor increases with the air-fuel ratio and intake air temperature. 4. Difference of atomization rate between the ultrasonic atomization apparatus and the commercial carburetor increases with decreasing air-fuel ratio. 5. Droplet size is about 1-5.mu.m at the ultrasonic atomization apparatus, and 80-150.mu.m at the commercial carburetor, which indicates the ultrasonic atomization apparatus is excellent in atomization.

• Journal of Biosystems Engineering
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• 제22권1호
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• pp.59-67
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• 1997

An experimental apparatus was developed for the rapid determination of thermal conductivity by transient probe method. The theoretical basis for transient probe method has been investigated. The mathematical model for this method is the Carslaw and Jaeger model which is used perfect line source theory. The small needle probe which is equipped with thermocouple and heating element is constructed. A software that performs data analysis and acquisition is programmed. The influence of the power dissipated per unit length of the probe has been assessed for glycerin. The result showed no significant correlation between thermal conductivity and power input. Determination made with this experimental apparatus were found to agree well with the recommended thermal conductivity data.