• 대한수학교육학회지:학교수학
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• 제1권1호
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• pp.39-58
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• 1999

Nowadays, open education is popular in Korea. Various open education methods such as open time, open space, open curriculum, team teaching, small group learning are actively introduced into mathematics education. Current 'open education in mathematics' in Korea can be characterized as the application general education reform movement (open education movement) to mathematics education. This movement is interested in teaching methods rather than contents. In this article, I discussed with the limits and the problems of this application and argued that not the method-centered open general education reform movement but the content-centered mathematics education's own reform movement is necessary for the true mathematics education reform.

• 공학교육연구
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• 제21권2호
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• pp.39-50
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• 2018

In the 4th industrial revolution, the maker movement is spreading around the world with the fusion of advanced technology with product manufacturing. Already in developed countries such as the US and Japan, the emphasis is on maker education that integrates education into traditional makers' movement. Through this, we are fostering young talents who will lead the fourth industrial revolution era. Domestic maker education is mainly performed in the maker space, and is limited to the IT field using Arduino and App-Inventor. Therefore, it has the limitation of fostering IT-oriented makers. Therefore, it is affecting the proliferation of the maker's movement because of the difficulty of participation of the general public. The purpose of this study was to understand the characteristics of maker 's movement and to suggest the direction of Korean maker education. In order to accomplish the purpose of research, we analyzed the case of convergent maker education at D Creation Economic Innovation Center, which combines IT and culture technology. We conducted a case study on maker education(VR production project, electronic publishing, beads craft, leather craft, IoT) which was held from July 8 to August 30, 2017 five times. We conducted interviews with five preliminary makers who participated in all the courses of the education, and five instructors who acted as professional makers with pre- developed questionnaires. The results of the study were derived by applying the Thematic Analysis method after opening the contents of the interview. Based on the results of the study, we could suggest characteristics of Korean makers and future direction of maker education.

• 제어로봇시스템학회논문지
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• 제20권5호
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• pp.481-485
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• 2014

In service robots, a number of human movements are analyzed using a variety of sensors. Vibration signals from walking movements of a human provide useful information about the distance and the movement direction of the human. In this paper, we measure the intensity of vibrations and detect both human walking pace and direction. In our experiments, vibration signals detected by microphone sensors provide good estimation of the distance and direction of a human movement. This can be applied to HRI (Human-Robot Interaction) technology.

• International Journal of Internet, Broadcasting and Communication
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• 제10권4호
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• pp.70-74
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• 2018

In order to ensure the flow of goods available and more flexible, reduce labor costs, many factories and industrial zones around the world are gradually moving to use automated solutions. One of them is to use Automated guided vehicles (AGV). Currently, there are a line tracing method as an AGV operating method, and a method of estimating the current position of the AGV and matching with a factory map and knowing the moving direction of the AGV. In this paper, we propose ceiling Light and guided line based moving direction estimation algorithm using multi-camera on the AGV in smart factory that can operate stable AGV by compensating the disadvantages of existing AGV operation method. The proposed algorithm is able to estimate its position and direction using a general - purpose camera instead of a sensor. Based on this, it can correct its movement error and estimate its own movement path.

• 한국기계가공학회지
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• 제7권1호
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• pp.75-80
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• 2008

This paper presents a new precision moving instrument for the displacement and direction control using the uni-morph type PZT actuator. The instrument is composed of the two-body and a link. The body has the uni-morph type PZT actuator, which make the vibration. Movement of simple moving instrument is generally analyzed by the theory of center-of-gravity moment. However the analysis of the instrument in this paper is focused the resonance of instrument. Resonance of the body is originated a uni-morph type PZT actuator that is vibrated by voltage and frequency. The basic performances of one body instrument are analyzed by the FEM analysis. And experiments are also performed to confirm the linear movement of the instrument and direction control. it is proper a voltage control than a frequency control for the direction changing. And Moving velocity is 0.032m/s.

• 한국정밀공학회지
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• 제12권12호
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• pp.130-138
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• 1995

Machined graphite/epoxy surfaces were studied by using SEM (Scanning Electron Microscopy), surface profilometry and its analysis to determine suitable surface describing parameters for machined unidirectional and multidirectional laminate composite. The surface roughness and profile are found to be highly depdndent on the fiber layup direction and the measurement direction. It was possible to machine 90 .deg. and -45 .deg. plies due to the adjacent plies, which were holding those plies. It was found that the microgeometrical variations in terms of roughness parameters $R_{a}$ without $D_{y}$(Maximum Damage Depth) region and $D_{y}$are better descriptors of the machined laminate composite surface than commonly used roughness parameters $R_{a}$and $R_{max}$ The characteristics of surface profiles in laminate composite are well represented in CPD (Cumulative Probability Distribution) plot and PPD (Percentage Probability Density) plot. Edge-trimmed multidirectional laminate surfaces are Gaussian and random for profiles measured along the tool movement direction, they are periodic and non-Gaussian in the direction perpendicular to the tool movement.t.ent.t.

• 대한치과보철학회지
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• 제28권1호
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• pp.43-61
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• 1990

The laser reflexion method is a new technique which permits precise contactless measurement and observation of tooth mobility as well as tooth movement. The purposes of this study were to clarify the reliability of the laser reflexion method in clinical application and to measure the abutment tooth movement according to clasp design. This study was designed to determine 1) How much a bending movement of the impression plate stand affects the position of the reflexion pattern and how precise the patient bites into plate 2) Which clasp design causes greater movement of the abutment tooth. Under medium and maximum bite forces, tests were performed on central loading position which was 13mm distal to terminal abutment tooth of distal extension removable partial denture. The movement in the mesiodistal and buccolingual directions was measured. The Duncan's New Multiple-Range test was used to compare the means for the four castings under each direction-load combination; and the paired sample t-test was for medium and maximum bite forces. From this experiment, the following results were obtained. 1. The Roach clasp, the combination clasp, the RPI clasp, and the Akers clasp did not significantly differ in their effects on buccolingual movement of the abutment tooth. 2. The direction of abutment tooth movement was not significantly altered by clasp design and all abutment tooth movements were oriented distobuccally. 3. Under medium bite force, the Akers clasp caused greater distal movement of the abutment tooth than did the combination clasp and the RPI clasp. Under maximum bite force, the Akers clasp caused greater distal movement of the abutment tooth than did the RPI clasp. 4. The testing apparatus and procedures used in this study(laser reflexion method) proved to be reliable in clinical application.

• Fibers and Polymers
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• 제7권2호
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• pp.191-194
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• 2006

This paper adopts nonlinear vibration method to analyze the fluctuation process of fiber movement. Based on Hamilton Principle, this paper establishes differential equation of fiber axial direction movement. Using variable-separating method, this paper separates time variable from space variable. By using the disperse movement equation of Galerkin method, this paper also discusses stable region of transition curve and points out those influencing factor and variation trend of fiber vibration.

• Journal of the Korean Wood Science and Technology
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• 제35권4호
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• pp.1-8
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• 2007

목재의 방향별 내부수분이동계수와 표면방사계수를 측정하기 위하여 2.5 (방사방향) ${\times}$ 2.5 (접선방향) ${\times}$ 2.5cm (섬유방향)의 낙엽송 정육면체 시편을 제작하였다. 수분이동방향과 직교하는 단면을 제외한 나머지 4면을 파라핀테이프와 고무테이프를 이용하여 코팅한 후, 70, 50, $30^{\circ}C$의 3가지 온도조건과 30, 60%의 2가지 상대습도 조건에서 건조시키면서, 목재 내부와 표면에서의 수분이동을 평가하였다. 자유수 유동과 결합수 및 수증기의 확산에 의한 내부수분이동계수는 고온조건에서 크게 나타났으며, 섬유방향이 횡단방향에 비하여 6배, 횡단방향에서는 방사방향이 접선방향에 비하여 1.2배 정도 큰 값을 보였다. 표면방사계수는 온도가 상승하고, 표면함수율이 감소함에 따라 증가하였다. 본 연구 결과를 이용하여 비평형상태에서 낙엽송재 내 함수율 분포변화와 증발수분량을 예측할 수 있으리라 기대된다.

• The Journal of Korean Physical Therapy
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• 제27권2호
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• pp.81-84
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• 2015

Purpose: The purpose of this study was to compare the effect of 'knowledge of result' and 'knowledge of performance', two types of extrinsic feedbacks, during the sit-to-stand movement in children with hemiplegic cerebral palsy. Methods: A total of ten children with hemiplegic cerebral palsy (ages 8 to 12 years) were recruited for the study. Subjects with hemiplegic cerebral palsy performed sit-to-stand movement in front of a mirror. Their performance was supervised and revised for normal movement by a pediatric physiotherapist. In the knowledge of the result, subjects performed sit-to-stand using a chair with an armrest in their mind with normal movement. In the knowledge of performance, subjects performed sit-to-stand under verbal instructions. Randomized cross over trials were used in this study. Main outcome measurements were as follows: mediolateral speed, anteroposterior speed, velocity moment, extent in mediolateral direction, extent in anteroposterior direction, and vertical distance of the center of pressure. Results: The mediolateral speed and extent of center of pressure was higher for 'knowledge of performance' in comparison with the other type of extrinsic feedbacks (p<0.05). The other parameters, including anteroposterior speed and extent, and vertical speed of the center of pressure, did not differ between the two types of extrinsic feedbacks (p>0.05). Conclusion: These findings suggested that training in sit-to-stand movement with 'knowledge of result' may result in better use of extrinsic feedback.