• Journal of the Korean Ceramic Society
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• v.31 no.12
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• pp.1501-1506
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• 1994

The precipitate of FeCl2.4H2O and NaOH, Fe(OH)2 was rapidly made to oxidize by H2O2 to prepare $\delta$-FeOOH. The particle size, surface and morphology of $\delta$-FeOOH, and the shape and structure of thermally decomposed $\delta$-FeOOH were investigated by the use of high resolution STEM. $\delta$-FeOOH prepared under the condition of reaction temperature of Fe(OH)2 at 4$0^{\circ}C$, [OH-][Fe2+]=5 and aging time of 2 hr Fe(OH)2, had 630$\AA$ mean particle size, 4~5 aspect ratio, 20.8 emu/g saturation magnetization and 210 Oe coercivity. The edges of $\delta$-FeOOH were inclined to (001) about 41$^{\circ}$, 60$^{\circ}$ and coincident with (102), (101) respectively. When $\delta$-FeOOH was thermally decomposed at 25$0^{\circ}C$ for 2 hr in vacuo, which had micropores of 0.9 nm thickness and crystallites of 2.4 nm thickness. (001)hex, [10]hex. of $\delta$-FeOOH parallel with (001)hex, [100]hex. of $\alpha$-Fe2O3 respectively. This showed three dimensional topotaxial structure transition, which was investigated by SADP (Selected Area Diffraction Pattern) of STEM.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.227-230
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• 2005

Virtual reality(VR) is both one of the high-technology and main paradime in leading next genaration of 21th century. It's application spectrum is various and lead to numorous revolotion as well as transition in technical aspect. These change is a good procept of it's value and influence effect in global fields of human life. In this paper, Location of specific portion of the image which it comes to receive at real-time tracking using WebCam, The method research which is the possibility of doing location tracking which is accurate

• The Journal of Information Systems
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• v.21 no.3
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• pp.163-186
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• 2012

With the development of Internet and transition to information society, social capital is expanding to online from the traditional offline context. Especially with the widespread of social network service(SNS) the number of SNS users is increasing sharply and the importance of online social capital has been more and more significant. Most studies on social capital focused on organizational aspects but few studies have payed attention to personal aspect. Empirical studies on the relation between SNS and social capital were seldom conducted in previous studies. Based on the theory of social capital this study targets on the relationship formed through SNS and analyzes on how the relationship affects the perceived social capital. In this study 'self-presentation', 'playfulness' and 'critical mass' are posited as the antecedent factors of 'SNS usage'. This study proposes a research model to examine the effect of 'SNS usage' on 'relationship reinforcement', 'relationship building' and 'perceived social capital'. According to the results of empirical analysis, 'self-presentation', 'playfulness' and 'critical mass' can generate significant positive influence on 'SNS usage'. It also confirms not only the effect of 'relationship reinforcement' and 'relationship building' formed through SNS on 'perceived social capital' but also relationship between the social capital formation and SNS usage. The outcome obtained in this study can be applied in developing SNS services.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.8
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• pp.945-956
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• 1999

This work reports a set of approximate analytical solutions describing the initial transient process of close-contact melting between a rectangular parallelepiped solid and a flat plate on which either constant temperature or constant heat flux is imposed. Not only relative motion of the solid block tangential to the heating plate, but also the density difference between the solid and liquid phase is incorporated in the model. The thin film approximation reduces the force balance between the solid weight and liquid pressure, and the energy balance at the melting front into a simultaneous ordinary differential equation system. The normalized model equations admit compactly expressed analytical solutions which include the already approved two-dimensional solutions as a subset. In particular, the normalized liquid film thickness is independent of all pertinent parameters, thereby facilitating to define the transition period of close-contact melting. A unique behavior of the solid descending velocity due to the density difference is also resolved by the present solution. A new geometric function which alone represents the three-dimensional effect is introduced, and its properties are clarified. One of the representative results is that heat transfer is at least enhanced at the expense of the increase in friction as the cross-sectional shape deviates from the square under the same contact area.

• Convergence Security Journal
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• v.8 no.1
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• pp.91-100
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• 2008

The previous works in sensor networks security have focused on the aspect of confidentiality, authentication and integrity based on cryptographic primitives. There has been no prior work to assess the survivability in systematic way. Accordingly, this paper presents a survivability model of wireless sensor networks using software rejuvenation for dual adaptive cluster head. The survivability model has state transition to reflect status of real wireless sensor networks. In this paper, we only focus on a survivability model which is capable of describing cluster head compromise in the networks and able to switch over the redundant cluster head in order to increase the survivability of that cluster. Second, this paper presents how to enhance the survivability of sensor networks using software rejuvenation methodology for dual cluster head in wireless sensor network. We model and analyze each cluster as a stochastic process based on Semi Markov Process (SMP) and Discrete Time Markov Chain (DTMC). The proof of example scenarios and numerical analysis shows the feasibility of our approach.

• Journal of Digital Contents Society
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• v.14 no.3
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• pp.303-311
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• 2013

On original exhibits, which is passive and repeat itself endlessly irrelevant of the present of spectators, reduce its immersion. Therefore in this paper, we propose the scheme to recreate original exhibits be adding automatic screen saver by using division of different images to make experimental of an area of different images, to judge movement, maintain conditions or to propose the transition of mechanism. By implementing and analyzing this automatic screen saver, which was made through the scheme of proposition, we show the positive aspect of the use of centralized automatic screen saver.

• Cross-Cultural Studies
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• v.39
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• pp.83-95
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• 2015

Every country has a dark history in the process of transition to a modern state. Many countries have until the 21st century, especially in East Asia, colonialism, has experienced conflict influenced, racial discrimination, the trauma of such massacre. Such a dark history in many countries are also still in progress. Dark History of China, which maintains the proletarian dictatorship is the 'Cultural Revolution(Wenhua da Geming)'. 'Cultural Revolution' is neither the outer aspect of the ideological struggle, but in fact it was not even class struggle ideology and class struggle. Put an end to the feudal intellectuals in China in the course of the tragedy stood and lead to build a new China suffered the humiliation of being betrayed from state power. Chinese writers after the 'Cultural Revolution' ended, was created in the process of creation reflects the tragedy of the 'Cultural Revolution' in the country(national memory) is suffering from the pain and suffering the same growth process as it saw this novel growth experienced in the personal growth process. "Road leaving at 18 years" of WiHua has ruled out the pain of growing national attention wholly to personal growth and pain. Such "Road leaving at 18 years" in the sense suggests the possibility of a typical growth story in China Contemporary Literature.

• International Journal of High-Rise Buildings
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• v.12 no.1
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• pp.35-47
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• 2023

The transport system and its infrastructure are not only the fundamental means of sustaining the operation of contemporary cities, but also important drivers for the evolution of urban form. Rail transit, critical to improving the operational efficiency and optimizing the spatial layout in cities, is one of the critical conditions for high-density areas with limited land and concentrated resources to be compact to take on complex challenges. As a node element of infrastructure, rail transit entrances are the most important points connecting the rail transit system with urban space. Although influenced by urban form, their quantity and location also influence and shape the evolution of urban space form. Based on the development gap of high-density areas in various contexts, focusing on various rail transit stations in Asia, this research analyzes the correlation between rail transit entrances and peripheral high-density urban form in a delicate, dynamic and granular way. The research considers both horizontal and vertical perspectives, in combination with the urban evolution process in time series, to explore the development trend of high-density urban form in Asia from the aspect of correlation, and building a new foundation for research on urban form, suitable for different types of cities.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.6
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• pp.556-562
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• 2023

This paper presents the development and market trends of nano biosensors. These biosensors must possess high sensitivity and selectivity to effectively detect diseases. Presently, many research groups are focusing on the field-effect transistor aspect of nano biosensors, which can identify diseases such as Down syndrome, bladder cancer, breast cancer, and numerous other cancers, utilizing graphene and transition metal dichalcogenide materials. In the case of in-vitro diagnostics, the use of nano biosensors has been rapidly growing since the onset of the COVID-19 pandemic. This paper also discusses market trends and the outlook for both national and international enterprises engaged in the nano biosensor field. Nano biosensors are expected to play a beneficial and significant role soon, contributing to the early diagnosis of diseases and subsequently improving patient outcomes.

• International Journal of High-Rise Buildings
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• v.13 no.1
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• pp.97-102
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• 2024

In this paper, we would like to share our ongoing research on global population and demographic shifts and the corresponding need for diverse responses. As population growth varies worldwide, the pressing issue is the current global housing shortage. The USA alone lacks 4 million homes, underlining the urgency for new construction and renewal of existing. Our focus is primarily on new building processes, which must also incorporate elements of renewal for future sustainability. Our research addresses several key questions: How will roles for construction professionals change? What should be the primary goal of the design process? What types of technologies are currently available, and which aspects of the process can be enhanced with AI? A significant part of our study is exploring sustainable building methods that reduce embodied carbon and increase speed of construction. Our goal is to extend the transition from smart homes to cities, analyzing the evolution towards smart communities and cities. A critical aspect of our research is the 'kit of parts concept, involving prefabrication and modular construction. This approach is essential for both rebuilding and new projects, potentially lowering costs in manufacturing and design for long term. Lastly, we present a detailed comparison of the construction industry with manufacturing.