• Journal of the Korea Society of Computer and Information
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• v.8 no.3
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• pp.53-60
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• 2003

In these day, Digital Contents is authorized in forms of HTML and various kind of multi-media by an enterprise and/or organization. At this circumstances, it is very hard or impossible to search a contents between them. Futhermore, you may have to change your contents service systems to extend to cover more user services needs. On this paper, we propose a new architecture to get extendability and empowered interoperability without any maintenance, update or changes. And we introduce the OMG's CORBA to make fault resilient system and to provide a load balancing using a distributed process mechanism. Even more, we adopted the SyncML specification. It can help us to make it real to synchronize between DBMS at real-time. So all these are support easy content synchronization and user-friendness.

• Journal of Information Display
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• v.12 no.1
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• pp.37-41
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• 2011

Presented herein is a novel stereoscopic three-dimensional (3D) display system with active color filter glasses. This system provides full-color 3D images by applying the time-multiplexing technique on the original anaglyph method. By switching between the opposite anaglyph statuses, a full-color anaglyph is presented. A liquid crystal panel from a 3D monitor serves as an active color filter operating at 120 Hz. A display panel and a color filter are connected to one graphic card as a dual-link system, for synchronization. To test the quality of this system, a left/right-eye image separation test and an experiment with stereoscopic images were carried out. Although there was some crosstalk and blur, the system, as expected, provided full-color 3D display. This system overcomes a monochromatic 3D image, which is the major weakness of the original anaglyph system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.10
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• pp.1117-1130
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• 1992

In this study, we propose a protocol for the communication between process groups required during message transfers. This is accomplished by an efficient process management of distributed systems connected by computer networks. For a single process group, a multicast protocol was proposed, which can control message flows while maintaining the order of messages sent or delivered. Through use of membership-related services, a member composing a process group may leave and join the current a membership anytime during execution. Moreover, message delivery can be delayed by using a logical vector time stamp. The functionality of the message delivery includes a virtual synchronization in response to a change in membership.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.2
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• pp.366-368
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• 2015

This paper proposes a MAC protocol for sensor networks such as disaster detection system which generate the non-periodic packet. B-MAC has been used to solve delay problem for sensor networks, however, the power loss occurs due to excessive preamble and over-hearing. In contrast, S-MAC has a number of drawbacks in power consumption due to synchronization. In this paper, we propose H-MAC and analyze its performance which has improved power consumption compared to S-MAC and overhead and over-hearing compared to B-MAC.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.6
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• pp.611-618
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• 2016

The suggested paper studies communications network and system technology, designing data to sync to both USB memories and cloud storages at the same time, which would allow users to safely keep and manage data even in case of network troubles, affecting cloud storages, and/or loss of physical USB memories, resulting in lost data in the physical memory. The need of secure data management policy for cloud storage users form the basis of this study, offering solutions to network failures and loss of physical storage by creating hybrid cloud system. To provide convenience to windows users, the UI design should integrate that of windows explorer to maximize security and convenience.

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.159-165
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• 2005

The proposed optical transmitter is composed of FF(flip flop) , PLL (phase locked loop), reference clock generator, serializer and LD driver 10x250 Mb/s data arrays are translated to the 2.5 Gb/s data signal by serializer. In this case, 1 data bus is allocated usually as a reference clock for synchronization. In this proposed optical transmitter, 125 MHz reference clock is generated from 10x250 Mb/s data arrays by reference clock generator. From this method. absent of reference clock bus is available and more data transmission become possible. To achieve high speed operation, the serializer circuit is designed as two stacks. For 10:1 serialization, 10 clocks that have 1/10 lambda differences is essential, so the VCO (voltage controlled oscillator) composed of 10 delay buffers is designed. PLL is for runing at 250 MHz, and dual PFD(phase frequency detector) is adopted for fast locking time. The optical transmitter is designed by using 0.35 um CMOS technology.

• Journal of Navigation and Port Research
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• v.31 no.9
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• pp.763-769
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• 2007

A narrow loop noise bandwidth method is desirable to reduce the error of raw measurements due to the thermal noise. However, it degrades the performance of GPS initial synchronization such as mean acquisition time. And it restricts the loop noise bandwidth to a fixed value determined by the lower bound of the allowable range of carrier-to-noise power ratio, so that it is difficult to optimally track GPS signal. In order to make up for the weak points of the fixed-type narrow loop noise bandwidth method and simultaneously minimize the error of code and carrier measurements, this paper proposes a stepwise-type adaptive bandwidth algorithm for DGPS reference receivers. In this paper, it is shown that the proposed adaptive bandwidth algorithm can provide more accurate measurements than those of the fixed-type narrow loop noise bandwidth method, in view of analyzing the simulation results between two signal tracking algorithms. This paper also carries out sensitivity analysis of the proposed adaptive bandwidth algorithm due to the estimation uncertainty of carrier-to-noise power ratio. Finally the analysis results are verified by the experiment using GPS simulator.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.08a
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• pp.91-94
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• 2008

As the mobile devices and the wireless networks have high-performance capabilities, it is possible to synchronize the spatio-temporal data of a server with the spatio-temporal data of a mobile device which are collected at a field. However, since the server process the synchronization which the model device requests, the whole synchronizations of mass mobile devices take long time. In this paper, we propose the scheme to process concurrently the synchronizations of mobile devices which does not conflict with others using the scheme of a multi-queue.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.10
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• pp.894-900
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• 2012

Indoor wireless positioning system uses ranging information of beacons in order to precisely estimate a tag location. To estimate distance between each beacons and tag, the system calculates arrival time of a tag pulse with clock of each beacon including independent clock offset. This clock offset seriously affects the performance of ranging and positioning. We propose in this paper a clock offset compensation method to solve this problem. To verify the performance of the proposed method, we simulated location estimation with random clock offset between -1,000ppm and 1,000ppm, and the result shows that the proposed scheme effectively solves the clock offset problem.

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