• Journal of The Korean Association of Information Education
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• v.10 no.1
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• pp.93-104
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• 2006

The purpose of this study is to examine the effects of GLAS(Guided-Learner Adaptable Scaffolding) strategies in web-based collaborative learning environments. Through the extensive literature reviews, web-based collaborative learning environments considering GLAS types were developed. 93 sixth graders were selected from a elementary school in Seoul, and they learned in the web-based system for 4 weeks. The results revealed that the impact of scaffolding on transfer of learning, cognitive overload by reflective scaffolding, learning motivation affected intrinsic scaffolding.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.73.2-73.2
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• 2010

In order to understand internal dynamics of starless cores, molecular line emissions are usually observed. From profiles of the molecular lines, internal motions of starless cores have been deduced using a simple radiative transfer model such as the two-layer model (Myers et al.1996). This brings complexities arising from the chemical evolution. The motivation of this study is to follow the chemical evolution of a starless core that goes through gravitational contraction. For this purpose, we have performed hydrodynamical simulations with a marginally unstable Bonnor-Ebert sphere as an initial condition. We follow the chemical evolution of this core with changing conditions such as the chemical reaction rate at the dust surface and the strength of radiation field that penetrate into the core. At the core center, the molecules suffer from a higher degree of molecular depletion on the dust covered by ice rather than on the bare silicate dust. The stronger radiation field dissociates more molecules at the core envelope. From analysis on the line profile using the two-layer model, we found that the speed of inward motion deduced from the HCN F = 2-1 line adequately traces the true infall speed, when the dust is covered by ice and the core is exposed to the diffuse interstellar radiation field. Under different conditions, the two-layer model significantly underestimate the infall speed.

• International Journal of Advanced Culture Technology
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• v.6 no.4
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• pp.12-19
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• 2018

This article aims to discuss the transition of the Kazakh writing system from Cyrillic to Latin. First, the study investigates the relationship between the Kazakh Cyrillic alphabet and phonology, in order to linguistically evaluate the efficiency of the writing system. Second, the process of determining the Kazakh Latin alphabet is discussed in terms of the Kazakh phonological system. Third, the factors that determined the Latin alphabet of Kazakh language are analyzed. In Kazakh, the phonemic system is subject to controversy among linguists, but it can be said that the phonological system basically follows the one-to-one correspondence to the Russian and Kazakh phonemes. As for the depth of orthographies, Kazakh Cyrillic writing system is not based on the shallow orthographies, so it incorporates morphophonemic information to make skilled readers understand easier. The political and social aspects are considered as a cause of the alphabet change. Although there are studies suggesting the conversion of the writing system is caused by the extrinsic factors rather than the intrinsic factors, the five criteria of Smalley (1964), which compromise the intrinsic and extrinsic factors, are also persuasive. The five factors are 1) Maximum motivation for the learner, 2) Maximum representation of speech, 3) Maximum ease of learning, 4) Maximum transfer, 5) Maximum ease of reproduction.

• Journal of radiological science and technology
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• v.35 no.2
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• pp.109-117
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• 2012

The purpose of this work was to evaluate an amorphous silicon cesium iodide based indirect flat-panel detector (FPD) in terms of their modulation transfer function (MTF), Wiener spectrum (WS, or noise power spectrum, NPS), and detective quantum efficiency (DQE). Measurements were made on flat-panel detector using the International Electrotechnical Commission (IEC) defined RQA3, RQA5, RQA7, and RQA9 radiographic technique. The MTFs of the systems were measured using an edge method. The WS(NPS) of the systems were determined for a range of exposure levels by two-dimensional (2D). Fourier analysis of uniformly exposed radiographs. The DQEs were assessed from the measured MTF, WS(NPS), exposure, and estimated ideal signal-to-noise ratios. Characteristic curve in the RQA3 showed difference in the characteristic curve from RQA5, RQA7, RQA9. MTFs were not differences according to x-ray beam quality. WS(NPS) was reduced with increasing dose, and RQA 3, RQA5, RQA7, RQA9 as the order is reduced. DQE represented the best in the 1mR, RQA 3, RQA5, RQA7, RQA9 decrease in the order. The physical imaging characteristics of FPD may also differ from input beam quality. This study gives an initial motivation that the physical imaging characteristics of FPD is an important issue for the right use of digital radiography system.

• Journal of Biomedical Engineering Research
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• v.28 no.6
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• pp.756-767
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• 2007

For the combination of phosphor screens having various thicknesses and a photodiode array manufactured by complementary metal-oxide-semiconductor (CMOS) process, we report the observation of image-quality degradation under the irradiation of 45-kVp spectrum x rays. The image quality was assessed in terms of dark pixel signal, dynamic range, modulation-transfer function (MTF), noise-power spectrum (NPS), and detective quantum efficiency (DQE). For the accumulation of the absorbed dose, the radiation-induced increase both in dark signal and noise resulted in the gradual reduction in dynamic range. While the MTF was only slightly affected by the total ionizing dose, the noise power in the case of $Min-R^{TM}$ screen, which is the thinnest one among the considered screens in this study, became larger as the total dose was increased. This is caused by incomplete correction of the dark current fixed-pattern noise. In addition, the increase tendency in NPS was independent of the spatial frequency. For the cascaded model analysis, the additional noise source is from direct absorption of x-ray photons. The change in NPS with respect to the total dose degrades the DQE. However, with carefully updated and applied correction, we can overcome the detrimental effects of increased dark current on NPS and DQE. This study gives an initial motivation that the periodic monitoring of the image-quality degradation is an important issue for the long-term and healthy use of digital x-ray imaging detectors.

• Korean Institute of Interior Design Journal
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• v.22 no.4
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• pp.70-77
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• 2013

This study has analysed the composition elements in a cafe space where visual transfer-elements are filled and the perceptual characteristics of facade designs with the purpose of drawing any important elements to advertisement and their related items for uniqueness of designs. For the analysis of the perception process shown in the consecutive situations of observing and visiting cafes, the cafe facade was grouped and stereotyped for the analysis of perceptual characteristics and significant composition elements for better designing of cafes through survey with representative facades as subjects. The conclusions from this study are the followings. First, for the uniqueness specific to cafes to be integrated into facade, memory was chosen first as the most significant advertisement factor followed by interest as with male and attention as with female. The memory has much to do with furniture and finishing material of Clause (4), Chapter 4.1 and the types having effects on perception of Clause (1) and the atmosphere having effect on that of Clause (2) were found to be major factors to attention and interest. Second, it was found out that women preferred horizontally stable partition and men clearly divided facades. The factor of shape was observed first among the constituents of facade followed by color. There was no difference with 'shape' between men and women and color was found to be a space constituent having a lot of effects on women. Third, the memory of experience from visiting a cafe was very likely to offer the motivation of visiting it again, on which furniture had the most effect followed by finishing material and color. Such elevation elements as facade and logo were found not to have effect on the memory or the re-visit. Any intention of visiting again seemed to be influenced by such comprehensive images as atmosphere rather than by any concrete facade, furniture, or appliance. From the above viewpoint, facade design should have any uniqueness or impressive feature as well as the effect of making passers-by drop in and attracting them into the shop. The analysis of attributes of facade constituents revealed that the abstract images in addition to the configuration of facade had much to do with interest or behavior.

• Journal of Digital Convergence
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• v.16 no.6
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• pp.205-212
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• 2018

This Study aims to propose a new information security governance model design method for streamlining security governance at national strategic level. The research method of this study is to diagnose our operational experience and to derive a new model design method. In the meantime, national information security activities were perceived to be focused on knowledge transfer, and motivation of activities and securing of executive power were weak. As a result, security blind spots and frequent occurrence of large security incidents have become unresolved challenges. National cyber security governance should be grouped together as a whole systematically from the upper policy to the lower level of performance under the responsibility of the national leader. Based on this approach, this study presented the comprehensive framework of Korean security governance model and embodied it into four architectural designs such as vision, goal, process, and performance, thus deriving the foundation for future national governance model design. Further research is needed to diagnose problems in life cycle flow, security policies based on environmental changes, and new frameworks in which all subjects participate.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.3
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• pp.120-128
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• 2018

OLED Display fabrication system is one of the most complicated discrete processing systems in the world. As the glass size grows from $550{\times}650mm$ to $1,500{\times}1,850mm$ in recent years, the efficiency of Automated Material Handling System (AMHS) has become very important and OLED glass manufacturers are trying to improve the overall efficiency of AMHS. Aiming to meet the demand for high efficiency of transportation, various kind of approaches have been applied for improving dispatching rules and facility layout, while simultaneously considering the system parameters such as glass cassettes due date, waiting time, and stocker buffer status. However, these works did not suggest the operational policy and conditions of distribution systems, especially for handling unnecessary material flows such as detour. Based on this motivation, in this paper, we proposed an efficient algorithm for improving detour transportation in OLED FAB. Specifically, we considered an OLED FAB simplifying OLED production environment in a Korean company, where four stockers are constructed for the delivery of Lot in a bay and linked to processing equipments. We developed a simulation model using Automod and performed a numerical experiment using real operational data to test the performance of three operation policies under considerations. We showed that a competitive policy for assigning alternative stocker in case of detour was superior to the current dedicated policy using a specified stocker and other considered policies.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.662-665
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• 2017

Recently, the rapid development and development of the industrial environment has changed the talent that companies need. As the educational paradigm changes, the university education should complement the problems of the lecture education method (the existing knowledge transfer method) in order to cultivate the talents needed for the corporation. In order to improve self - directed and creative problem - solving ability, new teaching and learning methods are needed. In this study, we apply flip learning in the algorithm class which is an essential curriculum of computer engineering. This group is divided into groups that are combined with theoretical and practical lessons, and groups that have applied theoretical lessons by applying flip learning, and groups that employ traditional lecture techniques. To improve learner's learning motivation and academic achievement, we propose a flip learning teaching method suitable for the algorithm subject and apply it directly to the class. Based on the results, we compare and analyze the academic achievement and learning satisfaction of learners.

• Journal of Korean society of Dental Hygiene
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• v.18 no.4
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• pp.585-595
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• 2018

Objectives: The purposes of this study were to comprehend the subjective dental health status and the level of dental health knowledge in some middle school students and to analyze the correlation with dental health behaviors. Methods: A survey was conducted in some middle school students and the final 637 survey data were analysed. As the statistical analysis methods, the subjective dental health status, dental health knowledge and dental health behaviors according to the general characteristics were analyzed by independent t-test, one way ANOVA and Scheffe. The correlations among the subjective dental health status, dental health knowledge and dental health behavior were found by Pearson's correlation and multiple regression analysis. Results: Through correlation analysis of the subjective dental health status, dental health knowledge and dental health behavior, all showed a significant correlation. As a result of the factor analysis affecting dental behaviors, subjective dental health status was the highest (${\beta}=0.304$, p<0.001). Conclusions: The results of this study suggest that the improvement of subjective dental health status and dental health knowledge related to dental behaviors health in the middle school students should be considered. In addition, dental health education should focus on improving subjective dental health status through motivation rather than knowledge transfer training. Moreover, development programs appropriate for the middle school students whose behavioral changes are hard to obtain are needed.