• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.241-241
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• 2008

Macrofore formation in silicon and other semiconductors using electrochemical etching processes has been, in the last years, a subject of great attention of both theory and practice. Its first reason of concern is new areas of macropore silicone applications arising from microelectromechanical systems processing (MEMS), membrane techniques, solar cells, sensors, photonic crystals, and new technologies like a silicon-on-nothing (SON) technology. Its formation mechanism with a rich variety of controllable microstructures and their many potential applications have been studied extensively recently. Porous silicon is formed by anodic etching of crystalline silicon in hydrofluoric acid. During the etching process holes are required to enable the dissolution of the silicon anode. For p-type silicon, holes are the majority charge carriers, therefore porous silicon can be formed under the action of a positive bias on the silicon anode. For n-type silicon, holes to dissolve silicon is supplied by illuminating n-type silicon with above-band-gap light which allows sufficient generation of holes. To make a desired three-dimensional nano- or micro-structures, pre-structuring the masked surface in KOH solution to form a periodic array of etch pits before electrochemical etching. Due to enhanced electric field, the holes are efficiently collected at the pore tips for etching. The depletion of holes in the space charge region prevents silicon dissolution at the sidewalls, enabling anisotropic etching for the trenches. This is correct theoretical explanation for n-type Si etching. However, there are a few experimental repors in p-type silicon, while a number of theoretical models have been worked out to explain experimental dependence observed. To perform ordered macrofore formaion for p-type silicon, various kinds of mask patterns to make initial KOH etch pits were used. In order to understand the roles played by the kinds of etching solution in the formation of pillar arrays, we have undertaken a systematic study of the solvent effects in mixtures of HF, N-dimethylformamide (DMF), iso-propanol, and mixtures of HF with water on the macrofore structure formation on monocrystalline p-type silicon with a resistivity varying between 10 ~ 0.01 $\Omega$ cm. The etching solution including the iso-propanol produced a best three dimensional pillar structures. The experimental results are discussed on the base of Lehmann's comprehensive model based on SCR width.

• Information Systems Review
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• v.17 no.2
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• pp.101-132
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• 2015

National technical qualifications to enhance an individual's vocational skills, the competitiveness of companies and countries have an important function to improve. Especially 'qualifications' will have a signal function to show objectively measure an individual's ability with the 'Education' The "knowledge necessary for the performance of their duties. Technology will gain knowledge about such assessment or recognition is based on certain criteria and procedures." Learning to qualify are being made through a smart learning a lot. Due to the revolution of the Internet in recent years with the development of information and communication technologies are entering into a knowledge society, the importance of information and knowledge. This contemporary smart learning education system is continuing to rapidly growing in pace with the changing time and space constraints, without teaching and learning is taking place. The purpose of this study is the ARCS motivation theory can determine a representative theory of human motivation factors and basic psychological needs dealing with the human nature of the psychological needs Interactivity and immersive learning, and to validate the empirical causality Affecting the continued use of smart learning through fun. Specifically, attention, relevance, confidence in the ARCS motivation, see their effect on the learning flow through the satisfaction we analyze empirically. Through this national technical qualifications smart learner's learning by supporting the implicit synchronization of students in learning are the degree of continued use. Therefore, to achieve the objectives of national technical qualifications and skills through a smart learning can contribute to the activation of the development and certification of course industry.

• The Journal of Society for e-Business Studies
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• v.12 no.3
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• pp.211-234
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• 2007

In e-business, XML is a major format of data and it is essential to efficiently process queries against XML data. XML query caching has received much attention for query performance improvement. In employing XML query caching, some efficient technique of cache replacement is required. The previous techniques considered as a replacement unit either the whole query result or the path in the query result. The former is simple to employ but it is not efficient whereas the latter is more efficient and yet the size difference among the potential victims is large, and thus, efficiency of caching would be limited. In this paper, we propose a new technique where the element in the query result is are placement unit to overcome the limitations of the previous techniques. The proposed technique could enhance the cache efficiency to a great extent because it would not pick a victim whose size is too large to store a new cached item, the variance in the size of victims would be small, and the unused space of the cache storage would be small. A technique of XML semantic cache replacement is presented which is based on the replacement function that takes into account cache hit ratio, last access time, fetch time, size of XML semantic region, size of element in XML semantic region, etc. We implemented a prototype XML semantic cache system that employs the proposed technique, and conducted a detailed set of experiments over a LAN environment. The experimental results showed that our proposed technique outperformed the previous ones.

• Journal of Korea Multimedia Society
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• v.8 no.7
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• pp.924-942
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• 2005

Recently, large-scale directories have been developed for LINUX cluster file systems to store and retrieve huge amount of data. One of them, GFS directory, has attracted much attention because it is based on extendible hashing, one of dynamic hashing techniques, to support fast access to files. One distinctive feature of the GFS directory is the flat structure where all the leaf nodes are located at the same level of the tree. Hut one disadvantage of the mode structure is that the height of the mode tree has to be increased to make the tree flat after a byte is inserted to a full tree which cannot accommodate it. Thus, one byte addition makes the height of the whole mode tree grow, and each data block of the new tree needs one more link access than the old one. Another dynamic hashing technique which can be used for directories is linear hashing and a couple of researches have shown that it can get better performance at file access times than extendible hashing. [n this research, we have designed and implemented an extendible hashing directory and a linear hashing directory for large-scale LINUX cluster file systems and have compared performance between them. We have used the semi-flat structure which is known to have better access performance than the flat structure. According to the results of the performance evaluation, the linear hashing directory has shown slightly better performance at file inserts and accesses in most cases, whereas the extendible hashing directory is somewhat better at space utilization.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.129-145
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• 2022

Purpose: This study aims at preparing an external evacuation system by setting up situation that may occur outside buildings in case of large-scale fire at buildings such as multiuse facilities and presenting appropriate response procedures and action instructions for evacuees and facility managers. Method: Major matters are summarized based on various situations which may occur outside in case of fire and the contents of fire manual. Necessary factors including risk alert standards in the event of fire and the role of building occupants are classified and then important issues are summarized. In addition, the definition of fire-related outside shelters and external evacuation routes are showed, and then the applicability to the shelters and the routes are reviewed for old apartments in Jung-gu among multi-dense facilities. Result: Four stages (attention, caution, alert, serious) for standards of fire risk warning are established with the results of the investigation and analysis, and guidelines for behavior for evacuees, facility owners, residents, managers are summarized and presented. In addition, the concept and role of external shelters are divided into primary to the third shelters, and matters related to the definition of each shelter and the establishment of evacuation routes are presented, and then considered them carefully. Conclusion: This study has highlighted the importance of suggesting a systematic plan to secure the safety for evacuees outside space of buildings with disorder and difficulty to control in the event of fire. Therefore, we are confident that it will be useful in making an integrated manual for inside and outside buildings.

• Journal of Engineering Education Research
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• v.4 no.1
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• pp.57-78
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• 2001

Due to developments in information technology and ensuing changes in the concept of time and space, the significance of national boundaries has been weakened, bringing to attention the heightened competition among nations. In order to respond to these transformations, the Korean government is increasing its efforts to raise the authenticity of the National Technology Qualification System(NTQS) by closely linking NTQS testing method and procedure to practical knowledge and skills in the industry field. This initiative is based on the recognition that the human resources development is a crucial factor in determining a nation's competitiveness. This study aimed, first of all, to diagnose the problems directly and indirectly affecting the testing method in the current NTQS. And then, differentiated solutions according to grade and improvements in the testing infrastructure were suggested. The ultimate purpose was to provide a blueprint for enhancing national competitiveness through increased authenticity and efficiency of the NTQS. Research methods applied during this study include: the collection and review of qualification-related literature; a series of conferences with leading experts; interviews with vocational educators and researchers from qualification-related institutes; a survey of national qualification holders from a variety of professions and industries; and participatory observation at qualification exam centers. This research suggested policy recommendations as follows; First, measures to improve for testing method of professional engineer Second, measures to improve for testing method of Master craftsman Third, measures to improve for testing method of Engineer, Industrial Engineer, Craftsman Fourth, plans for the establishment of operation system for a computerized testing Fifth, institutional perspective on establishing qualification infrastructure Sixth, operational perspective on establishing qualification infrastructure

• Cartoon and Animation Studies
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• s.39
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• pp.111-132
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• 2015

Although Rotoscoping technique has been used for a long time to mimic the natural and smooth motion since the early 20th century, its artistic value was devalued as tricks because it traces the already recorded images. But the fact that the rotoscoping images can cross the boundaries between animation and live action in an infinite integral freedom in the digital era became rather expansive new aesthetic possibilities of representation of the reality. In addition, Jonas Odell's animations such as (2010), (2008), (2006) are good example to prove that the rotoscoping images also can serve as means to enhance its narrative. This study is to analyze how rotoscoping images act as a unique role in relation with the narrative based on the said person's real stories and realistic images. I argue that his animated films constantly contain these three characteristics -Images to mediate Auditory sensitivity as a record of inner metaphysical reality, anonymous images to represent a specific existential character, and images that act as physical representation that holds the physical space/time and related memory. This reveals that rotoscoping images in this digital era went beyond reproduction for natural movements or special type of style. It rather suggests new layers of experience, and acquires new value in animation. I hope that this study could serve as a foundation to rediscover and re-position the value of rotoscoping images as well as good opportunity to introduce very talented swedish animation artist who already received global attention with his unique philosophical and aesthetic style.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.6
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• pp.491-496
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• 2021

In line with the modern era in which the safety of underground facilities and the use of underground information are increasingly emphasized, the state is pushing for more precise and accurate underground spatial information to be secured and utilized. Therefore, we need to pay more attention to subsurface geospatial data. In the future, the Ministry of Land, Infrastructure and Transport will actively utilize the 15 types of Integrated Underground Geospatial Information Map(6 types of underground facilities, 6 types of underground structures, 3 types of ground) that the Ministry of Land, Infrastructure and Transport is building as three-dimensional underground spatial information, and contribute greatly to improving national safety and convenience in underground construction. expected to do However, when a site manager requests an Integrated Underground Geospatial Information Map with a mobile device, if the large-capacity integrated underground space map is not quickly transmitted over the wireless section and is not serviced, it causes inconvenience to the site manager and delays work. In this paper, the goal of this paper is to enable field managers to quickly receive a tiled Integrated Underground Geospatial Information Map with minimal information exchange. Therefore, the tiling system is configured according to the dataset for high-speed Mobile Integrated Underground Geospatial Information Map transmission. In addition, a transmission system for the Mobile Integrated Underground Geospatial Information Map is established, and a TCP/IP (Transmission Control Protocol/Internet Protocol)-based spatial information tiling transmission protocol dedicated to the on-site Integrated Underground Geospatial Information Map is developed.

• Science of Emotion and Sensibility
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• v.23 no.2
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• pp.75-88
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• 2020

Given the development of information technology, various methods for efficient information delivery have been constructed as the method of delivering product information moves from offline and 2D to online and 3D. These attempts not only are about delivering product information in an online space where no real product exists but also play a crucial role in diversifying and revitalizing online shopping by providing virtual experiences to consumers. 360 product image is a photorealistic VR that allows a subject to be rotated and photographed to view objects in three dimensions. 360 product image has also attracted considerable attention considering that it can deliver richer information about an object compared with the existing still image photography. 360 product image is influenced by divergent production factors, and accordingly, a difference emerges in the responses of users. However, as the history of technology is short, related research is also insufficient. Therefore, this study aimed to grasp the responses of users, which vary depending on the type of products and the number of source images in the 360 product image process. To this end, a representative product among the product groups that can be frequently found in online shopping malls was selected to produce a 360 product image and experiment with 75 users. The emotional responses to the 360 product image were analyzed through an experimental questionnaire to which the semantic classification method was applied. The results of this study could be used as basic data to understand and grasp the sensitivity of consumers to 360 product image.

• The Journal of the Korea Contents Association
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• v.11 no.2
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• pp.178-185
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• 2011

The recent development of 3D and its application contents have made it possible for people to experience more various 3D contents such as 3D/4D, VR, 3D ride film, I-max, sensory 3D games at theme parks, large-scale exhibitions, 4D cinemas and Video ride. Among them, Video ride, a motion-based genre, especially is getting more popularity, where viewers are immersed in and get indirect experiences in virtual reality. In this study, the production process of the genre of sensory 3D image getting attention recently and ride film are introduced. In the material selection of 3D images, the space and the setting up which is suitable to the fierce movement of rides are studied and some examples of the realization of creative direction ideas and effective technologies using the functions of Stereo Camera which has been first applied to MAYA 2009 are also illustrated. When experts in this 3D image production create more interesting stories with the cultural diversity and introduce enhanced 3D production techniques for excellent contents, domestic relevant companies will be sufficiently able to compete with their foreign counterparts and further establish their successfully unique and strong domains in the image contents sector.