• Journal of The Korean Astronomical Society
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• v.36 no.3
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• pp.177-187
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• 2003

Active galactic nuclei (AGNs) are distant, powerful sources of radiation over the entire electromagnetic spectrum, from radio waves to gamma-rays. There is much evidence that they are driven by gravitational accretion of stars, dust, and gas, onto central massive black holes (MBHs) imprisoning anywhere from $\~$1 to $\~$10,000 million solar masses; such objects may naturally form in the centers of galaxies during their normal dynamical evolution. A small fraction of AGNs, of the radio-loud type (RLAGNs), are somehow able to generate powerful synchrotron-emitting structures (cores, jets, lobes) with sizes ranging from pc to Mpc. A brief summary of AGN observations and theories is given, with an emphasis on RLAGNs. Preliminary results from the imaging of 10000 extragalactic radio sources observed in the MITVLA snapshot survey, and from a new analytic theory of the time-variable power output from Kerr black hole magnetospheres, are presented. To better understand the complex physical processes within the central engines of AGNs, it is important to confront the observations with theories, from the viewpoint of analyzing the time-variable behaviours of AGNs - which have been recorded over both 'short' human ($10^0-10^9\;s$) and 'long' cosmic ($10^{13} - 10^{17}\;s$) timescales. Some key ingredients of a basic mathematical formalism are outlined, which may help in building detailed Monte-Carlo models of evolving AGN populations; such numerical calculations should be potentially important tools for useful interpretation of the large amounts of statistical data now publicly available for both AGNs and RLAGNs.

• Journal of Photoscience
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• v.11 no.3
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• pp.121-127
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• 2004

The${\beta}$-glucosidases occur widely in all living organisms and has in general a tendency to form oligomers of varying numbers of subunits or aggregates, although the functional implications of such diverse oligomerization schemes remain unclear. In particular, the assembly mode of the oat ${\beta}$-glucosidase is very unique in that it multimerizes by linear stacking of a hexameric building block to form long fibrillar multimers. Some structural proteins such as actin and tubulin assemble into long fibrils in a helical fashion and several enzymes such as GroEL and Pyrodictium ATPase functional complexes, 20S proteasome of the archaebacterium Thermoplasma acidophilum, and lutamine synthetase fromblue-green algae, assemble into discrete oligomers upto 4 stacked rings to maintain their enzymatic activities. In particular, oat ${\beta}$-glucosidase exists in vivo as a discrete long fibrillar multimer assembly that is a novel structure for enzyme protein. It is assembled by linear stacking of hollow trimeric units. The fibril has a long central tunnel connecting to the outer medium via regularly distributed side fenestrations. The enzyme active sites are located within the central tunnel and multimerization increases enzyme affinity to the substrates and catalytic efficiency of the enzyme. Although it is suggested that oligomerization may contribute to the enzyme stability and catalytic efficiency of ${\beta}$-glycosidases, the functional implications of such diverse oligomerization schemes remain unclear so far.

• Nuclear Engineering and Technology
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• v.49 no.3
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• pp.632-637
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• 2017

Even though the potential for an accident in nuclear power plants is very low, multiple emergency plans are necessary because the impact of such an accident to the public is enormous. One of these emergency plans involves a robotic system for investigating accidents under conditions of high radiation and contaminated air. To develop a robot suitable for operation in a nuclear power plant, we focused on eliminating the three major obstacles that challenge robots in such conditions: the disconnection of radio communication, falling on uneven floors, and loss of localization. To solve the radio problem, a Wi-Fi extender was used in radio shadow areas. To reinforce the walking, we developed two- and four-leg convertible walking, a floor adaptive foot, a roly-poly defensive falling design, and automatic standing recovery after falling methods were developed. To allow the robot to determine its location in the containment building, a bar code landmark reading method was chosen. When a severe accident occurs, this robot will be useful for accident condition monitoring. We also anticipate the robot can serve as a workman aid in a high radiation area during normal operations.

• Journal of the Korean Institute of Educational Facilities
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• v.26 no.3
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• pp.33-41
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• 2019

As the information age matures, the learning style of youth is changing rapidly. Students study at a variety of places such as cafe or lobbies utilizing various digital learning devices. Along with the place changes, learning methods are also changing. Student-centered learning methods such as smart learning, collaborative learning, and activity-based learning are increasingly being utilized instead of the traditional instructor-centered learning in which knowledge is unilaterally delivered. Accordingly, many universities are remodeling central libraries, and they are also transforming lobby spaces of the college buildings into simple but useful learning spaces. In this study, we analyze the characteristics of learning spaces in universities from the standpoint of the students. According to the analysis, overall satisfaction is high in terms of comfortable physical learning environments such as Wi-Fi, furniture, lighting, etc. But the spaces are still optimized for individual and intensive learning. There seems to be a lack of effort to support collaborative learning or activity-based learning. This observation is confirmed by the characteristics of the central library, and it is considered that the reason why the college buildings are preferred by students is that college buildings are more suitable for collaborative or activity-based learning than libraries.

• Advances in concrete construction
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• v.7 no.1
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• pp.39-50
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• 2019

This study presents a comprehensive experimental investigation on mostly encountered types of Reinforced Concrete Haunched Beams (RCHBs) where three modes of RCHBs investigated; the diversity of studied beams makes it a pioneer in this topic. The experimental study consists of twenty RCHBs and four prismatic beams. Effects of important parameters including beam type, the inclination angle, flexure and compressive reinforcement, shear reinforcement on mechanical behavior and failure mode of each mode of RCHBs were examined in detail. Furthermore crack propagation at certain load levels were inspected and visualized for each RCHB mode. The results confirm that RCHBs have different behavior in shear as compared to the prismatic beams. At the same time, different mechanical behavior was observed between the modes of RCHBs. Therefore, RCHBs were classified into three modes according to the inclination shape and mode of failure (Modes A, B and C). However, it was observed that there is no significant difference between RCHBs and prismatic beams regarding flexural behavior. Moreover, a new and unified formula was proposed to predict the critical effective depth of all modes of RCHBs that is very useful to predict the critical section for failure.

• Journal of Korean Society of Rural Planning
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• v.25 no.1
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• pp.39-50
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• 2019

The purpose of this study is to figure out the current condition of local governments (Si or Gun) to implement rural development policy in the face of the central government's drive for increasing devolution. Since late 1990s or early 2000s when scope of rural policy began to expand quantitatively, there has been considerable increase in rural residents' participation into community projects as a whole. Nevertheless, there exists regional differentiation in local governments' efforts to systematically support rural development projects (CRDP: Comprehensive Rural Development Programme) and community activities by setting up intermediary organizations or hiring rural development professionals in a public office. According to this survey on local government officials, regions that have made such efforts to support rural policy at a local level, show more advanced level of institutional capacity than other regions in local decision making process for CRDP, role of strategic rural developmental plans, vitality of community actors, etc. In the era of increasing devolution, these differences can be expected to result in diverging performances of each area in regionalized rural policy. The central government needs to introduce EU's LEADER-type rural development programmes to support community acitivities by various local actors and at the same time promote local governance building for rural policy, adopting institutional rewarding system such as rural planning contract.

• Journal of Korean Society for Quality Management
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• v.49 no.1
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• pp.31-45
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• 2021

Purpose: A noncentral composite design method is to be developed to explore farther region for the first factorial design. A general guideline for sequential experimentation is provided. Methods: (1) A non-overlapping noncentral composite design (NNCD) is developed, in which the second factorial design shares one design point that indicates the best response value in the first factorial design. (2) Four composite designs are compared in terms of the four design evaluation criteria, which are D-, A, G, and I-optimality. (3) A follow-up design strategy is suggested based on the interaction effect, direction of improvement, number of factors. Results: (1) NNCD and model building method are presented, which is useful for exploring farther region from first factorial design block. (2) The performances of the four composite designs are compared. (3) A follow-up design strategy is suggested. Conclusion: (1) NNCD will be useful to explore farther region for the first factorial design. (2) A follow-up design strategy can be beneficial to the experimental practitioners for product and process design and improvement.

• SUVANNABHUMI
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• v.12 no.1
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• pp.7-47
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• 2020

This article is a sub-section of a comparative analysis of depictions of violence in Jakarta's Museum of the Indonesian Communist Party's Treachery, Ho Chi Minh City's War Remnants Museum, and Phnom Penh's Tuol Sleng Genocide Museum. In comparing these public history sites, I analyze how memories of mass violence were central to state formation in both Suharto's anti-Communist New Order (1966-1998), the Socialist Republic of Vietnam (1976-present), and Cambodia since the collapse of Democratic Kampuchea (1979-present). While this comparison points out specific distinctions about the role of the military, the nature of revolution, and conceptions of gender, it argues for a central similarity in the use of a mythology of victimization in building these post-conflict nation-states. This article focuses on my gendered analysis of the use of images of women and children in each museum. Depending on context and political purpose, these museums cast women as tragic victim, revolutionary heroine, or threat to the social order. My analysis of gender places stereotypical images of violence against women (the trope of women and children as the ultimate victims) in conversation with dark fantasies of women as perpetrators of savage violence and heroic images of women liberated by participation in violence.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.5
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• pp.75-86
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• 2022

The service industry has been acknowledged as a critical part of mobile banking services in recent years. This study examines the impact of e-service quality and loyalty on the intention to use and use behavior of mobile banking services in Mongolia, a Central Asian country. As a result, based on past research, a conceptual model was suggested. This study comprises 209 completed questionnaires from young Mongolians who own a bank account and a smartphone. The data was collected based on convenience sampling, and it was analyzed with SmartPLS software using a partial least squares-structural equation modeling (PLS-SEM) technique. The findings indicate that system quality, interface design, and security assurance have a significant positive impact on service quality; service quality has a positive impact on loyalty. Moreover, the results reveal that service quality and loyalty have a significant influence on the intention to use mobile banking services. The findings of this study suggest that local or international banks and financial institutions in Mongolia should consider system quality, interface design, and security concerns as key successors to building perceived security quality to retain current mobile banking users and attract new customers.

• Journal of the Korean association of regional geographers
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• v.10 no.1
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• pp.9-22
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• 2004

This paper aims to identify the role of local governments in building regional innovation system. The central government has recently decided to support the promotion of innovation capacities of local innovators and innovation networks among thor The central government forces local governments to establish the council for regional innovation in order to implement these goals. Meanwhile, there is no consensus about the way in which the council for regional innovations constitute and operate. I think it is the time for us to talk about this seriously. It is widely conceived that local governments in Korea have still been hierarchical. Thus, they would be difficult to make the decision effectively on regional innovation and development initiatives. In this context, I suggest that the regional innovation promoting agency needs to take authorities to secure transparency and autonomy in planning, implementing, evaluating regional innovation initiatives. The local government no! ed to play a central role in establishing the agency. However, the local government should not try to intervene and control its operations.