• 한국작물학회지
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• 제54권4호
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• pp.366-374
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• 2009

벼 품종특성을 고려한 입형분리 최적조건을 설정하기 위하여 다양한 입형 특성을 갖는 41품종의 쌀을 입형분리의 체눈 직경 3.5, 3.8 및 4.2 mm, 싸라기 수거함의 각도 5, 15, $30^{\circ}$ 조건에서 싸라기 분리능을 비교시험 하였고 다음과 같은 결과를 얻었다. 1. 싸라기 제거율은 기기적 측면에서 체눈의 직경과 깊이 및 싸라기 수거함의 각도, 품종적 측면에서 쌀알의 폭, 길이 및 천립중에 의해 주 영향을 받았다. 2. 싸라기 수거함의 각도는 지면과의 수평한 입형분리체 원통직경을 0도로 할 때 +5도와 +15사이에서 분리능이 좋았으며, +5도 이하에서는 완전미손실율 증가하고 각도가 높아질수록 완전미 손실율은 감소하나 분리된 싸라기 량도 감소되었다. 3. 기존 벼 품종에서 쌀알 기준으로 폭과 길이가 각각 2.9와 5.2 mm이상이고, 천립중이 22g 이상일 경우 4.2 mm이상, 폭이 작고 소립인 경우 3.8 mm, 그 밖의 중소립종은 3.8~4.2 mm의 체눈 직경이 적합할 것으로 판단되었다. 4. 립장이 작고, 립폭은 상대적으로 크면서 두께가 얇은 품종은 그렇지 않은 품종보다 싸라기 분리능이 떨어지는 경향이었으며, 품종에 따라 입형분리기 체눈의 직경은 크고 깊이는 얕은 체 눈 규격이 필요한 것으로 생각되었다. 5. 싸라기 비율이 상대적으로 지나치게 높을 경우에는 다소 완전미율의 소실이 있더라도 권장 체눈 크기보다 큰 쪽을 택하는 것이 싸라기 제거량을 높일 수 있었다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.67.1-67.1
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• 2011

Knowledge of the solar radiation components and classified wavelength are essential for modeling many solar energy systems. This is particularly the case for applications that concentrate the incident energy to attain high photo-dynamic efficiency achievable only at the higher intensities. In order to estimate the performance of concentrating solar systems, it is necessary to know the intensity of the beam radiation, as only this components can be concentrated, and The new solar system can generate electricity from ultraviolet and infrared light as well as visible light. The Korea Institute of Energy Research(KIER) has began collecting solar radiation components data since January, 1988, and solar radiation classified wavelength data since November, 2008. KIER's solar radiation components and classified wavelength data will be extensively used by concentrating solar system users or designers as well as by research institutes.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.84-90
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• 2009

The gravel ballast in the ballasted track has the function to not only transfer/scatter the train loads to subgrade through rail and sleeper but also elastically support the train loads. Because track irregularities results inevitably from the repetitive train loads, the track maintenance should be undertaken for correcting them. By analyzing the track maintenance history in the Gyeongbu high speed railway, this study tries to choose the local two spots in the railway in which the repair frequencies are maximum and relative small; to analyze their dynamic characteristics as well as grade; and to compare them with maintenance history. As the dynamic characteristics of track, the vertical displacement and vibrating acceleration of sleeper as well as acceleration of ballast are measured/analyzed. Furthermore, by collecting soil and gravel on the reinforced roadbed and undertaking ballast screening test, the size distributions are compared with grade distribution standards of high speed railway.

• Educational Technology International
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• 제14권1호
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• pp.27-40
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• 2013

Design-Based Research (DBR) focuses on developing key principles of interventions to advance both theory and practicalities of dissemination (Brown, 1992), yet its methodological details have not been quite established. Thus, the purpose of this paper is to address the pragmatics of DBR by sharing the researcher's reflections on conducting a longitudinal DBR project for five years. In an attempt to advance college teaching practices as well as theories related to student plagiarism, the project focused on refining "humble" theories on how and why college students engage in plagiarism to design classroom interventions for promoting academic integrity. Similar to the Integrative Learning Design (ILD) framework proposed by Bannan-Ritland (2003), but conducted in a much simpler and less formal format, this study followed DBR cycles from initial conceptualization to design and enact instructional interventions in authentic contexts while collecting both quantitative and qualitative data from each phase. Finally, the paper addresses some challenges encountered throughout the DBR project as well as the lessons learned from this experience. Like many previous DBR studies whose practical relevance is limited to local context, the findings from this study may not be easily generalized for other contexts.

• 한국과학교육학회지
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• 제31권1호
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• pp.115-127
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• 2011

본 연구에서는 탐구 기능 가운데 자료 수집, 자료처리, 자료 해석과 관련하여 실험보고서 분석틀을 개발하였다. 또한 개발한 분석틀을 대학생들의 보고서 분석에 적용하여 오차와 불확도 개념을 중심으로 대학생들이 보고서 작성에서 어려움을 겪고 있는가에대해 알아보았다. 물리실험 수업을 수강한 30명의 학생들에게 실시한 설문지와 학생들이 작성한 실험보고서를 분석하였다. 학생들은 자료 수집과 관련하여 반복 측정에 대해 인식을 하고 있으나 보고서에서는 이를 명확하게 표현하지 못하였다. 극값이나 기울기가급하게 변하면 더욱 정밀한 측정을 해야 하지만 학생들은 이 부분에서도 어려움을 지니고 있었다. 특히, 오차와 불확도와 관련하여 학생들은 많은 어려움을 표출하고 있었다. 오차와 불확도의 전파에 대한 이해도가 매우 낮은 상태에서 단순한 오차 전파공식도 이용하지 못하는 학생이 많았다. 오차와 불확도를 분석을 통해 자료를 해석하는 과정에서도 많은 어려움을 겪고 있었는데, 오차의 원인들이 결과에 어떻게 영향을 주는지를 정량적으로 분석할 수 있는 학생은 거의 없었다. 반면에 학생 대부분이 오차와 불확도 분석이 중요하다고 응답하였다. 학생들이 중요성을 인식하고 있으나 올바른 개념을 지니지 못하여 보고서 작성에서 어려움을 겪고 있다는 결론을 내릴 수 있었다. 실험 수업에서 보고서를 통해 과학적 의사소통을 해야하는 학생들에게 물리 개념뿐만 아니라 자료를 수집하고 처리하고 해석하는 데 필요한 기본 개념에 대한 교육이 필요할 것이다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.3046-3051
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• 2011

The third-rail system is an important device supplying power directly to the Maglev train through physical contact with the collecting shoe. It is directly related to safety and reliability for the running of Maglev. However, most the third-rail system used in Korea depend on foreign product or technologies, Korea Urban Maglev in the development of appropriate power feeding is urgent. In particular, the turnout section is the weakness point in the system because bending force by turnout section movement and fatigue caused by repetitive motion as well as the expansion by temperature, the forces by Maglev collecting shoe is added th the third-rail. Therefore, this paper proposes the third-rail system appropriate for Korean Urban Maglev of turnout section. To verify the structural stability of POSCO ICT third-rail system, the finite element analysis and physical testing was performed. The third-rail is fixed on each side of the turn-out section steel structure by epoxy insulation supporter and the integral behaviors are occurred. Therefore, the maximum horizontal displacements of each support are investigated and then, it is applied to finite element model of the third-rail to investigate the moments and stress. Also, the bending test about one million times and Expansion Joint for the third-rail was performed. The third-rail system safety and reliability was identified by test line on Korea Institute of Machinery & Materials in Deajeon for under the actual usage environment such as the Maglev and turn-out operation.

• International Journal of Aeronautical and Space Sciences
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• 제10권1호
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• pp.98-103
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• 2009

The forecasting, mitigation and preparedness of the natural disaster impacts require relevant information regarding the disaster desirable in real time. In the meantime it is requiring the rapid and continuous data and information generation or gathering for possible prediction and monitoring of the natural disaster. Since disasters that cause huge social and economic disruptions normally affect large areas or territories and are linked to global change. The use of traditional and conventional methods for management of the natural disaster impact can not be effectively implemented for intial data col1ection with the further processing. The space technology or remote sensing tools offer excellent possibilities of collecting vital data. The main reason is capability of this technology of collecting data at global and regional scales rapidly and repetitively. This is unchallenged advantage of the space methods and technology. The satellite or remote sensing techniques can be used to monitor the current situation, the situation before based on the data in sight. as well as after disaster occurred. They can be used to provide baseline data against which future changes can be compared while the GIS techniques provide a suitable framework for integrating and analyzing the many types of data sources required for disaster monitoring. Developed GIS is an excellent instrument for definition of the social impact status of the natural disaster which can be undertaken in the future database developments. This methodology is a good source for analysis and dynamic change studies of the natural disaster impacts.

• 한국항행학회논문지
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• 제20권1호
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• pp.86-92
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• 2016

최근 사람이 다수 붐비는 지역에 스마트 폰이나, 태블릿 등을 바로 충전할 수 있는 태양광 모듈이 설치되어 서비스를 제공하고 있다. 하지만 설치비용이 높아 이용인원이 적은 지역에 설치 할 경우 비용측면에서 부담이 되며, 협소한 지역에는 설치가 어려운 문제점이 존재한다. 본 논문에서는 이와 같은 문제를 해결하기 위해 국가에서 제공하는 데이터와, 실제 환경에서 수집한 데이터를 이용하여 각 지역에 해당 서비스를 제공받는 사람에 대한 정보를 분석 한 후 대기시간 및 태양광 충전시간을 고려하여 환경에 맞는 최적의 전력을 수집 및 제공하는 시스템을 제안하였다. 실험결과 수집전력이 충전전력량보다 상회하여 충전이 지연되지 않았으며, 약 95분경에 스마트 폰의 전력을 모두 충전할 수 있음을 확인하였으며, 버스 대기시간인 10분에서 20분 사이에 스마트 폰이 한 대일 경우 약 50%가량을 충전할 수 있으며, 여러 대일 경우 약 20%가량을 충전할 수 있음을 확인하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권3호
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• pp.943-961
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• 2020

With the advent of IoT technology and Big Data computing, the importance of WSNs (Wireless Sensor Networks) has been on the rise. For energy-efficient and collection-efficient delivery of any sensed data, lots of novel wireless medium access control (MAC) protocols have been proposed and these MAC schemes are the basis of many IoT systems that leads the upcoming fourth industrial revolution. WSNs play a very important role in collecting Big Data from various IoT sensors. Also, due to the limited amount of battery driving the sensors, energy-saving MAC technologies have been recently studied. In addition, as new IoT technologies for Big Data computing emerge to meet different needs, both sensors and sinks need to be mobile. To guarantee stability of WSNs with dynamic topologies as well as frequent physical changes, the existing MAC schemes must be tuned for better adapting to the new WSN environment which includes energy-efficiency and collection-efficiency of sensors, coverage of WSNs and data collecting methods of sinks. To address these issues, in this paper, a self-organization scheme for mobile sensor networks with mobile multiple sinks has been proposed and verified to adapt both mobile sensors and multiple sinks to 3-dimensional group management MAC protocol. Performance evaluations show that the proposed scheme outperforms the previous schemes in terms of the various usage cases. Therefore, the proposed self-organization scheme might be adaptable for various computing and networking environments with big data.

• 품질경영학회지
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• 제44권4호
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• pp.713-733
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• 2016

Purpose: The primary objective of this case study is to establish a COQ(Cost of Quality) management system for power generation industries. Key topics of this study include collecting COQ elements, their classifications, COQ computation formula, and determining COQ improvement projects. Results: A comprehensive set of COQ elements have been isolated for electric power generation companies. The COQ elements were classified in such a way that they could be managed according to the PAF model as well as the SIPOC diagram. This study showed that a systematic approach could be established for monitoring the COQ elements and using them in the process of improving quality competitiveness. Methods: The PAF(Prevention-Appraisal-Failure) model has been employed in the process of collecting COQ elements for a power generation company. All the cost of quality elements were first examined through an extensive review of articles and books in the field of quality. The cost elements were then refined and augmented by conducting a comparative study with international standards. The COQ elements have been verified by a group of quality managers and classified according to both the PAF model and the SIPOC diagram for better understanding in the entire organization. An improvement strategy has been also proposed by using a typical COQ level of power generation companies. Conclusion: The conventional PAF model was used in establishing a COQ management system for power generation industries. This case study illustrates the procedure about identification, classification and computation of quality costs, including selection of improvement projects. The system can be used not only for observing the current state of cost elements related to quality, but also for planning an improvement strategy using the ratio of cost classification.