• Journal of Astronomy and Space Sciences
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• v.29 no.3
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• pp.321-328
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• 2012

We have designed a 30 cm cryogenic space infrared telescope for astronomical observation. The telescope is designed to observe in the wavelength range of 0.5~2.1 ${\mu}m$, when it is cooled down to 77 K. The result of the preliminary design of the support structure and support method of the mirror of a 30 cm cryogenic space infrared telescope is shown in this paper. As a Cassegrain prescription, the optical system of a 30 cm cryogenic space infrared telescope has a focal ratio of f/3.1 with a 300 mm primary mirror (M-1) and 113 mm secondary mirror (M-2). The material of the whole structure including mirrors is aluminum alloy (Al6061-T6). Flexures that can withstand random vibration were designed, and it was validated through opto-mechanical analysis that both primary and secondary mirrors, which are assembled in the support structure, meet the requirement of root mean square wavefront error < ${\lambda}/8$ for all gravity direction. Additionally, when the M-1 and flexures are assembled by bolts, the effect of thermal stress occurring from a stainless steel bolt when cooled and bolt torque on the M-1 was analyzed.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.352-356
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• 1990

In this paper proposed a new analysis method that can be controlled DC separately excited motor using DC chopper. An analysis method can be broadly divided the state variables method and the state space averaging method. The state variable method is largely used for analysis method in the time area, but it is complicated analysis of the nonlinear circuit and modeling of the system. Therefore a boundary of the current continuous mode and discontinuous mode can be definited by the state space averaging method. Also this paper proposed a new approximation analysis method using state space averaging method in the discontinuous mode.

• East Asian mathematical journal
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• v.26 no.4
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• pp.553-579
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• 2010

Geometric education emphasize reasoning ability and spatial sense through development of logical thinking and intuitions in space. Researches about space understanding go along with investigations of space perception ability which is composed of space relationship, space visualization, space direction etc. Especially space visualization is one of the factors which try conclusion with geometric problem solving. But studies about space visualization are limited to middle school geometric education, studies in elementary level haven't been done until now. Namely, discussions about elementary students' space visualization process and ability in plane or space figures is deficient in relation to geometric problem solving. This paper examines these aspects, especially in relation to plane and space problem solving in elementary levels. Firstly we propose the analysis frame to investigate a visualization process for plane problem solving and a visualization ability for space problem solving. Nextly we select 13 elementary students, and observe closely how a visualization process is progress and how a visualization ability is played role in geometric problem solving. Together with these analyses, we propose concrete examples of visualization ability which make a road to geometric problem solving. Through these analysis, this paper aims at deriving various discussions about visualization in geometric problem solving of the elementary mathematics.

• Korean Institute of Interior Design Journal
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• v.20 no.6
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• pp.331-339
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• 2011

The purpose of this study was to examine wandering behaviors of the elderly with dementia at elderly care facilities, thus finding out the current status of supportability and safety of wandering space for facility residents and looking into the convenience of management for the control and Support of the elderly with dementia in wandering space, from the aspect of managers. Study methods consisted of literature examination, on-site assessment and investigation, observation and questionnaire survey. And via a questionnaire survey of facility workers at study subject facilities, the current status and facility workers' perception of wandering space and their job-satisfaction were examined. Collected data of 133 respondents were used for analysis. Data were processed with the SPSS 18.0 program, and such analytic techniques as frequency, percentage, mean, multiple response analysis, chi-square test and correlation analysis were carried out. The problems of physical environment of wandering space for the elderly with dementia: First, it is urgent to establish wandering space. Second, thoughtlessly installed chairs in the corridor impeded wandering behaviors. Third, the grips installed in the corridor space were irregular, thus causing inconvenience for wandering behaviors. Thus making residents' use of it difficult. In order to improve these problems, it is necessary to newly or additionally establish wandering space and modify the location of chairs or establish alcoves, thus reducing impedimentary elements for wandering behaviors. Providing a proper wandering space is important for facility residents. And it is also important for facility workers to manage facility residents.

• Journal of Korean Library and Information Science Society
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• v.51 no.2
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• pp.245-272
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• 2020

The purpose of this study is to analyze the current status of space use in university library and draw up considerations for enhancing space utilization based on the analysis results. For this purpose, the utilization rate of each space was analyzed by categorizing the user's space of the university library, and secondly, the preferences of the major user groups were analyzed according to the characteristics of the users' space. For empirical analysis, we collected and refined users' space usage data (98,282 people's data 433,769 cases) accumulated for one year for the central library of "J" National University. Then we analyzed the usage pattern according to space and period(monthly, hourly). In addition, preferences for each major group of users (undergraduates, graduate students and graduates) in the library were analyzed through the library visitors' data (2,426,553 cases) over the same period. The results of this study can be used as preliminary research for the composition and arrangement of users' space in future university libraries.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.9
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• pp.795-801
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• 2014

STEP Cube Lab. classified as a pico-satellite has been being developed by SSTL(Space Technology Synthesis Laboratory) in Chosun University. Its main mission objective is to perform the on-orbit verification of core space technologies, which will be the potential candidates for future space missions. In this paper, to guarantee successful mission operation of the cube satellite under extremely severe space thermal environment condition, the system level thermal design and analysis has been performed. The effectiveness of the design has been verified through on-orbit thermal analysis of cube satellite.

• The Journal of Sustainable Design and Educational Environment Research
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• v.19 no.2
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• pp.11-20
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• 2020

The goal of this study was to investigate the implementation and related issues of the school space innovation issued by key Korean mass media using text mining. To accomplish this goal, this study collected 519 news articles associated with the school space innovation issued by 54 Korean mass media companies. Based on this data, this study performed the frequency analysis and network analysis regarding the keywords. Based on the findings, the characteristics of school space innovation are summarized as follows: First, school space innovation has progressed in response to future education. Second, users are actively participating in school space innovation. Third, experts are supporting the innovation of school space by establishing a cooperative system. Fourth, the community is actively considering the innovation of school space. Fifth, the main projects of the Ministry of Education and the Provincial Offices of Education are actively conducted in a mix of top-down and bottom-up approaches. The findings of this study will contribute to providing a clear direction for contemporary school space innovation and implications for future research agenda and implementation.

• Korean Institute of Interior Design Journal
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• v.18 no.6
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• pp.124-132
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• 2009

Recently, 'Emotion' has attracted public attention socially and continuously in the fields such as construction, environment, design and products. Also, phenomenological concept of space through the physique in the viewpoint of the human-oriented aspect, namely, body, has been managed as a planned measure suitable for a new era and space. In this study, the author examined and analyzed the verbs and emotional vocabulary about the human body's behavior. The phenomenological space conception through body, i.e, flesh in this human centered point of view is being treated as the suitable planning measure on the new era and space. Though the epochal issue for Emotion is being attempted in many ways in various field such as product and marketing, the approach through the relationship between human and space. Therefore, we would like to see how the Emotion related to the movement that occurs in the space by analyzing the human body movement which is the subject of experiencing the space experimentally and research the characteristic of Emotion and space movement. SPSS 12.0 was used for the analysis to perform the analysis of basic statistics and Factor Analysis, and then to analyze the characteristic and emotional attribute for the experimental analysis. Comparing the activity for the 2 groups' behavior through the analyzed result with the test, active behavior was found to be higher than inactive behavior in the emotional value, and their bodies' motion showed averagely positive value in the emotional aspect; their bodies' motion was presented differently according to the attributes and amount of the people who would experience a specific space. However, the author found that affirmative and active behavior showed emotional aspect more than inactive behavior.

• Korean Institute of Interior Design Journal
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• no.4
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• pp.5-9
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• 1995

In this study, the relationships between the interior space of the upper class residence of Korean late Chosun dynasty and human dimensions based on their life styles of that era are analized. As an object of the study, the interior space of Yunkyungdant in Changduk palace is selected. The major analytical frame works of this study are : the analysis of Space-Human Body System, the analysis of Space-Objects-Human Body System, and the analy-sis of Space-Objects-Human Body System, and the analy-sis of Space-Objects-Life Activities of Human Body System. As a result, it was verified that there are certain quantitative relationships between the interior space of the residence and the human dimensions of Koreans lived up to their life styles and activities of Chosun dynasty era, specialized as 'Confucian life style'.

• Korean Journal of Human Ecology
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• v.2 no.1
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• pp.110-113
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• 1999

Clothing shape is principally described in seven factors that are composed of clothing design, clothing material, clothing size, pattern design, sewing method and body motion etc. The aims of this study was to measurement out-line space-shape variation of clothing fitness with body by using the image processing. The subjects for direct anthropometric measurements were 248 female college students aged from 19 to 22. The data were statistically analyzed by principal analysis and cluster analysis. The results selected one somatotype. for the out-line space-shape variation of clothing fitness with body, there dimensional clothing shapes measured. and cross-sectional clothing shape obtained by the measurement was considered to be space wave form. The out-line space-shape variation of clothing fitness with body was observed between the node number and amplitudes of clothing wave form, and node number was determined at the maxim of space-shape amplitude, and the space-shape amplitudes have related with aspect ratio of cross-sectional shape. (Korean J of Human Ecology 2(1) :110-113, 1999)