• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.5
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• pp.413-421
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• 2015

Since the first Cubesat was launched in 2003, there have been more than 230 Cubesats launched so far. Due to their small size and lightweight, Cubesats were launched by utilizing the empty space of regular launch vehicle. However, this launch method has a weakness that has been easily affecting by the schedule of major payloads. As a new solution to this problem, it has been proposed that a robot arm installed on ISS would be used to launch Cubesats. The orbits of Cubesat deployed from the ISS in various angles and directions are analyzed in this paper. We also analyze the possibility of collision between the Cubesat and ISS within the operational orbit of the CubeSat and eventually calculate the optimal angle of a robot arm, which maximizes the lifetime of Cubesat and minimizes the risk of collision between the Cubesat and ISS.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.10
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• pp.875-887
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• 2015

The optimal layout design is used in the development of various areas of industry. In the field of space systems, components must be placed properly in the limited space of spacecraft by considering mechanical, thermal and electrical interfaces. When applying optimal layout design, a proper, even ideal placement of components is possible in the limited space of a satellite platform. Through the optimal placement design, the minimized moment of inertia enhances efficient attitude control, rapid maneuver and mission performance of the satellite. This paper proposes 3D optimal layout design that minimizes the spacecraft's moment of inertia and effect of thermal dissipation between inner components as well as interference between inner components based on a cubic-structure satellite platform. This study proposes the new genetic algorithm for 3D optimal layout design of the satellite platform.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.4
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• pp.73-82
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• 2018

In this study, we assessed meteorological and agricultural drought based on the SPI(Standardized Precipitation Index), SMP(Soil Moisture Percentile), and SMDI(Soil Moisture Deficit Index) indices using satellite-based TRMM(Tropical Rainfall Measuring Mission)/GPM(Global Precipitation Measurement) images at the province of Chungcheongbuk-do. The long-term(2000-2015) TRMM/GPM precipitation data were used to estimate the SPI values. Then, we estimated the spatially-/temporally-distributed soil moisture values based on the near-surface soil moisture data assimilation scheme using the TRMM/GPM and MODIS(MODerate resolution Imaging Spectroradiometer) images. Overall, the SPI value was significantly affected by the precipitation at the study region, while both the precipitation and land surface condition have influences on the SMP and SMDI values. But the SMP index showed the relatively extreme wet/dry conditions compared to SPI and SMDI, because SMP only calculates the percentage of current wetness condition without considering the impacts of past wetness condition. Considering that different drought indices have their own advantages and disadvantages, the SMDI index could be useful for evaluating agricultural drought and establishing efficient water management plans.

• Journal of Engineering Education Research
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• v.23 no.5
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• pp.76-85
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• 2020

The purpose of this study was to develop and validate a measurement scale of core competencies for one Institute of Science & Technology's students in South Korea. Based on the school's core value and mission, items were developed through document analysis, faculty survey, and experts' review. Initial sets of items were administered to students and results were analyzed to finalize the items for the scale, which consists of 4 core competencies (Creativity, Challenge, Collaboration, and Care) and 12 sub-competencies. Through reliability analysis and exploratory factor analysis, 56 items were selected. For a validity test, confirmatory factor analysis was conducted. Results suggest that the measurement scale is reliable and valid in measuring core competencies of students in an Institute of Science & Technology.

• Journal of Aerospace System Engineering
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• v.13 no.3
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• pp.32-39
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• 2019

Sensor pods mounted on the exterior of the aircraft used for tactical missions should have a fatigue life based on the expected load spectrum during operation. For mission equipment such as the sensor pod, the frequency fatigue life prediction method which applies the dynamic vibration environment condition is preferred due to the efficiency of the analysis. In this paper, a fatigue life prediction method in the frequency domain where stress due to static and dynamic loads is synthesized based on the actual flight load spectrum is proposed. After comparison with the existing analysis method, the fatigue life of the proposed analysis method was predicted conservatively. The proposed sensor pods satisfy the requirements of the fatigue life.

• Human Ecology Research
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• v.60 no.3
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• pp.407-427
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• 2022

The purpose of this study was to explore the implications of Freire's education theory for secondary school Home Economics Education (HEedu). We conducted a review of books written by Freire and classified the characteristics of his education theory into 9 categories. Based on these categories, we concretely explored the forms in which Freire's education theory could be applied in this area of education through interviews with Home Economics (HE) teachers. We also searched for activities that can be carried out by HEedu agents and the support that can be given by social institutions. The implications of Freire's education theory for HEedu are that education should exhibit love and respect for human beings, be ethically and democratically responsible, enable people to dream as well as hope, support consciousness and praxis by reflection, stimulate epistemological curiosity in learners' lives and experiences, promote subjectivity, autonomy and self-reliance, engage in dialogue to bring about a change in relationships rather than viewing dialogue as a skill, and stimulate political engagement. Freire's education theory therefore has multiple implications for the purpose, mission, and content of education, teaching methods and perspectives, and directions regarding the role of HE teachers. The results are expected to provide practical assistance in developing a persuasive curriculum for HEedu that can help learners restore subjectivity and love for human beings and their society by expanding the horizons of HEedu philosophy from the critical science of Habermas to Freire's education theory.

• Journal of Christian Education in Korea
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• v.69
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• pp.9-44
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• 2022

The purpose of this study is to restore religious education at home. Currently, Korean church education is facing a crisis. First, there is a decrease in the number of children in the church due to the problem of the low fertility rate. Second, the number of young people leaving the church is increasing. As a result, Maneun Church and church schools are being reduced or closed. In order to solve this problem, it is necessary to change from church school-centered education to family-centered faith education. This is because the restoration of faith education is also connected with the restoration of the Korean church in crisis. As an alternative to overcome the current crisis of church education, it is necessary to return to the original form of religious education. In other words, we must return to the way God commanded religious education through parents at home. The most important thing is to overcome and recover from the absence of religious education at home. A Christian home becomes a place of education that fulfills the primary responsibility of religious education for children. God has given his parents the primary authority and responsibility for the religious education of their children. However, amid changes in society and home, the educational function of the home was entrusted to other educational institutions or specialized teachers. Parents of Christian families tend to delegate their children's religious education to church schools by neglecting their educational authority and responsibility. Therefore, the purpose of this study is to reinforce that parents should have a Christian view of faith education and become the main agents of their children's faith education. Parents have the authority, responsibility, and duty as teachers for religious education given by God. The educational authority and responsibility of parents originate from God. God has commanded his parents to bring up their children in faith. Therefore, for parents to become the main agents of their children's religious education, restoration is needed in Christian home education. Therefore, the task of restoring the Christian family as a place of effective Christian education and fulfilling the educational mission of faith that God has given to parents is, first, that parents and the church must recognize the importance of Christian home education anew. Second, parents must have the correct awareness and mission in the Christian view of children. The mission of parents in a Christian home is to teach, train, and admonish their children in the Lord so that they can live with Christian values. Third, the church should actively support home education and form a deep bond between church education and home education.

• The Journal of Korean Academy of Sensory Integration
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• v.20 no.2
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• pp.46-55
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• 2022

Objective : This study aimed to explore the meaning of work experience of school-based occupatioanl therapists. Methods : This study was a phenomenological study. The participants were 7 school-based occupational therapists, all of whom were female with working experience of 5 years. One-on-One interviews were conducted with them about their work experience as school-based occupational therapists, and additional interview details were confirmed by e-mail. The interviews were recorded with the consent of the subjects. The researcher listened to the recordings several times prior to transcribing and analyzed the interviews according to Colaizzi's research method. Results : A total of 2 themes and 10 sub-themes were derived. Challenges and hopes were drawn as themes. The challenges theme included sub-themes administrative work burden, restriction of physical environment, lack of awareness of teachers, unstable employment, and legal restrictions. There were sub-themes such as sense of mission for children, team members with the same goal, children who want school-based occupational therapy, teacher' satisfaction, and responsibility for the development of school-based occupational therapy. Conclusion : Institutional improvement and policy support for school-based occupational therapy should be prepared to provide qualitatively improved school-based occupational therapy for special education subjects.

• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.183-184
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• 2012

We present the latest results from the Mission Program NIRLT, the NIR spectroscopic observations of brown dwarfs using the IRC on board AKARI. The near-infrared spectra in the wavelength range between 2.5 and $5.0{\mu}m$ is especially important to study the brown dwarf atmospheres because of the presence of non-blended bands of major molecules, including $CH_4$ at $3.3{\mu}m$, $CO_2$ at $4.2{\mu}m$, CO at $4.6{\mu}m$ and $H_2O$ around $2.7{\mu}m$. Our observations were carried out in the grism-mode resulting in a spectral resolution of ~ 120. In total, 27 sources were observed and 18 good spectra were obtained. We investigate the behavior of three molecular absorption bands, CO, $CH_4$ and $CO_2$, in brown dwarf spectra relative to their spectral types. We find that the $CH_4$ band appears in the spectra of dwarfs later than L5 and CO band is seen in the spectra of all spectral types. $CO_2$ is detected in the spectra of late-L and T type dwarfs.

• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.357-360
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• 2012

This paper presents $H{\alpha}$ emission line detections for four galaxies at z > 3.5 made with AKARI as part of the FUHYU mission program. These are the highest-redshift $H{\alpha}$ detections to date in star-forming galaxies. AKARI's unique near-infrared spectroscopic capability has made these detections possible. For two of these galaxies, this represents the first evidence of their redshifts and confirms their physical association with a companion radio galaxy. The star formation rates (SFRs) estimated from the $H{\alpha}$ lines under-predict the SFRs estimated from their far-infrared luminosities by a factor of ~ 2 - 3. We have also detected broad $H{\alpha}$ components in the two radio galaxies which indicate the presence of quasars.