• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2004.09a
• /
• pp.446-449
• /
• 2004

High resolution geophysical imaging to delineate costal aquifer and seawater- freshwater interface has been applied in Baesu-eup, Yeonggwang-gun, Jeolla province Electrical resistivity information from vertical electrical sounding and 2-D electrical resistivity survey is key parameter to map equivalent Nacl concentration map over the survey area. Seismic velocity from refraction tomographic survey, on the other hand, gives more reliable information on the subsurface stratagraphy than electrical resistivity methods which frequently suffer from low resolution due to masking effect. We imaged high-resolution 3-D structure of costal aquifer by correlating the electrical resistivity with seismic velocity, and mapped equivalent NaCl concentration map using resistivity and hydro-geological information from well logging.

• Korean Journal of Child Studies
• /
• v.22 no.2
• /
• pp.219-235
• /
• 2001

The purpose of this study was to provide guidelines for the effective operation of Web-Based Training (WBT) for early childhood teachers. Based on content analysis and questionnaires administered to the 174 current trainees, this research analyzed (1) the educational effectiveness and learner satisfaction, (2) the operation and management, and (3) the system, interface, interaction and communication, motivation and content design of $WBT^{***}$. Results showed that most trainees were very satisfied with the WBT because the program provided plentiful professional information enabling them to pursue their educational objectives along with flexibility of time and space. On the other hand, system stability, communication, motivation, and content design need to be improved. Based on the research results, 8 strategies of effective management of web-based early childhood teacher training were proposed.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2013.11a
• /
• pp.62-63
• /
• 2013

본 논문에서는 실제 수술환경에서 자연스러운 손 동작을 이용해 의료영상을 제어하고 동시에 관심 있는 환부의 영상을 획득할 수 있는 인터페이스를 제안한다. 특히 제안하는 인터페이스는 손을 들어올리는 등의 수술을 방해하는 동작을 강요하지 않음으로써 자연스러운 상호작용을 가능하게 하며, 또한 수술 영역에 수술 부위를 표시하고 저장하는 것과 같은 부가적인 기능을 제공하여 의사의 수술여건과 편의를 보장한다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2009.01a
• /
• pp.628-631
• /
• 2009

In this paper, we proposed a new authentication method using video that was taken during moving a hand-held camera in front of the face. The proposed method extracted individuality from the obtained image sequences using the parametric eigenspace scheme. Changes of facial appearance through authentication trials draw continuous tracks in the low dimensional igenspace. The similarity between their continuous tracks are calculated by DP-matching to verify their identities. Experimental results confirmed that different motions and persons change the shapes of continuous tracks, so the proposed method could identify the person.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.2 no.2
• /
• pp.109-112
• /
• 1997

Morphology of carbonate crystals grown on the surface of artificial cell membranes was controlled by changing the interfacial chemistry. For octadecyltriethoxysilane (OTE) films with terminal methyl groups interacting little with an aqueous calcium carbonate solution calcite (104) crystals were formed. Polymerized pentacosadiynoic acid (PDA) films with terminal carboxylic acid groups induced deposition of calcite (012) crystals aligned along with each other within a polymer domain. On the other hand, stearyl alcohol (StOH) films with terminal hydroxyl groups induced deposition of aragonite crystals. When PDA was mixed with StOH, the 8:1 PDA:StOH (molar ratio) film produced dominating calcite (012) crystals without any crystal alignment, and the 4:1 mixture film produced minor calcite (012) crystals and major aragonite crystals. For the 2:1, 1:1, 1:2, and 1:4 mixture films, aragonite crystals were dominating. Hence, it is found that the chemical composition at the interface plays a very important role in controlling the morphology of deposited carbonate crystals.

• Korean Journal of Materials Research
• /
• v.13 no.9
• /
• pp.598-605
• /
• 2003

The optimized conditions for the cross-sectional TEM sample preparation using tripod polisher and ion-beam miller was confirmed by AFM and TEM. For the TEM observation of interfaces including InGaN layers like InGaN/GaN MQW structures, the sample preparation by the only tripod polishing was useful due to the reduction of artifacts. On the other hand, in case of the thick nitride films like ELO, PE, and superlattice, both tripod polishing and controlled ion-beam milling were required to improve the reproducibility. As a result, the ion-beam milling with the $60^{\circ}$modulation showed the minimum height difference between film and sapphire interface and the ion-beam milling of the $80^{\circ}$modulation showed the broad observable width.

• Journal of Powder Materials
• /
• v.8 no.3
• /
• pp.179-185
• /
• 2001

Through the observation of wear scar of two ceramic materials, microstructural wear mechanisms was investigated. As for the $Al_2O_3$-5 vol% SiC nanocomposite, the grain boundary fracture was suppressed by the presence of SiC nano-particles. The intragranular SiC particles have inhibited the extension of plastic deformation through the whole grain. Part of plastic deformation was accommodated around SiC particles, which made a cavity at the interface between SiC and matrix alumina. On the other hand, gas-pressure sintered silicon nitride showed extensive grain boundary fracture due to the thermal fatigue. The lamination of wear scar was initiated by the dissolution of grain boundary phase. These two extreme cases showed the importance of microstructures in wear behavior.

• Korean Journal of Computational Design and Engineering
• /
• v.13 no.5
• /
• pp.323-333
• /
• 2008

Various virtual gloves have been developed for the past four decades. These gloves have sensors that can measure bending angles at finger joints and the positions as well as orientations of hands. Previous researches were mostly concentrated on utilizing different kinds of sensors. As the technology matured, more interests are given towards building virtual reality applications. Furthermore, due to the recent reduction of costs, these devices have been widely adopted. Our particular interest lies in three-dimensional applications where virtual objects are grasped and manipulated. For these applications, it is crucial to accurately measure finger joints angles for realistic object interactions with the virtual hand. With inaccurate measurements, virtual hands would penetrate inside virtual objects after they are grasped. Or alternatively, virtual objects would be grasped before hands are making any contacts with virtual objects. In this paper, we introduce new design of virtual gloves for improved finger joints measurements.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09b
• /
• pp.1130-1131
• /
• 2006

We found that the """interface reaction between Ni-based alloy bond, diamond, and steel core is very critical in bond strength of diamond tool. None element from metal bond diffuses into the steel core but the Fe element of steel core was easily diffused into the bond. This diffusion depth of Fe has a great effect on the bonding strength. The Cr in steel core accelerated the Fe diffusion and improved the bond strength, on the other hand, carbon decreased the strength. Ni-based alloy bond including Cr was chemically bonded with diamond by forming Cr carbide. However, the Cr and Fe in STS304 were largely interdiffused, the strength was very low. The Cr passivity layer formed at surface of STS304 made worse strength at commissure in brazing process.

• ETRI Journal
• /
• v.34 no.2
• /
• pp.245-255
• /
• 2012

Among emerging devices propelling the growth of mobile devices, smartphones and tablet-PCs are among the most recognizable. In this study, a research model is designed for exploring acceptance-diffusion strategies for tablet-PCs from the viewpoint of consumer perception, which is verified through a survey. The results of this study show that tablet-PCs have great potential to be versatile, multifunctional devices, even though they are currently considered mostly as entertainment-oriented rather than fulfilling the essential needs of everyday life. An analysis of the acceptance model for tablet-PCs revealed that playability, cost level, functionality, and complexity significantly affect user acceptance. An analysis of the diffusion model, on the other hand, showed that playability and user interface have a significant influence on satisfaction, trust, and positive behavioral intention. We also found that cost level is not a major hindrance in the market diffusion of tablet-PCs. The results of this study can be used to establish effective acceptance and diffusion strategies for tablet-PCs and other emerging devices.