• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.10a
• /
• pp.871-874
• /
• 2007

Stream data need a efficient data management with high reliability and real time processing. The characteristics of these data are a large volume, a short report interval and asynchronous report time. The typical queries of these systems consist of the current query to search the latest signal value, the snapshot query to search the signal value of a past time, the historical query to search the signal value of a past time to current. This paper proposes the efficient method to manage the above signals by using a file structured database in QNX operating systems. The query model to accommodate various query for stream data is proposed. The proposed methods are applied to reactive protection system to verify their usefulness. The COM(Cabinet Operator Module) based on the QNX employs file database that adopts a delta version and a buffering method for the resource limit of a small storage and a low computing power.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2000.10a
• /
• pp.426-432
• /
• 2000

This paper presents methods to design an integrated system for supporting both multimedia contents creations and its presentation in a windows system. Especially, it describes methods for designing an integrated editor that can be used to crate and edit various media data including continuous media such as audio and video. And it also proposes a system model for systematically integrating multimedia creating tool with multimedia presentation system where the heeling and scenario-based presentation methods are included in the propose system for supporting effective multimedia presentation through a network Finally, we describe a threads processing technique based on event monitoring to satisfy effectively needs for presentation control, synchronization control, and user's input control during a multimedia presentation.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.4 no.4
• /
• pp.835-843
• /
• 2000

This paper presents a method to design the integrated system for supporting both multimedia contents creation and its presentation in a windows system. Especially, it describes techniques for designing an integrated editor that can be used to crate and edit various media data including continuous media such as audio and video. And it also proposes a system model for systematically integrating multimedia creation tool with multimedia presentation system where the buffering and scenario-based presentation methods are included in the propose system for supporting effective multimedia presentation through a network. Finally, we describe a threads processing technique based on event monitoring to satisfy needs for presentation control, synchronization control, and user's input control during a multimedia presentation.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.15 no.4
• /
• pp.665-670
• /
• 2020

Buffer layer in CIGS thin-film solar cells improves energy conversion efficiency through band alignment between the absorption layer and the window layer. ZnS is a non-toxic II-VI compound semiconductor with direct-transition band gaps and n-conductivity as well as with excellent lattice matching for CIGS absorbent layers. In this study, the structural and optical properties of ZnS thin films, deposited by RF magnetron sputtering method and subsequently performed by the rapid thermal annealing treatment, were investigated for the buffer layer. The zincblende cubic structures along (111), (220), and (311) were shown in all specimens. The rapid thermal annealed specimens at the relatively low temperatures were polycrystalline structure with the wurtzite hexagonal structures along (002). Rapid thermal annealing at high temperatures changed the polycrystalline structure to the single crystal of the zincblende cubic structures. Through the chemical analysis, the zincblende cubic structure was obtained in the specimen with the ratio of Zn/S near stoichiometry. ZnS thin film showed the shifted absorption edge towards the lower wavelength as annealing temperature increased, and the mean optical transmittance in the visible light range increased to 80.40% under 500℃ conditions.