• Journal of Internet Computing and Services
• /
• v.7 no.3
• /
• pp.61-69
• /
• 2006

Data synchronization between data stored in mobile communication terminals and a central server is one of essential tasks for efficient mobile communication environments. Since, however, manufacturers of mobile terminals have their proprietary data synchronization mechanisms, data interoperability can hardly be achieved. Therefore, SyncML data synchronization mechanism in mobile communication environments was proposed as an open standard by OMA(Open Mobile Alliance). In this paper, a SyncML-based data synchronization gateway is designed and implemented which can process ActiveSync data also. In other words, by constructing a combined data synchronization gateway which can transform ActiveSync data into SyncML data, data interoperability between mobile terminals which use two different data synchronization mechanisms can be achieved, In addition, mobile communication experiments between ActiveSync-based terminals and a SyncML-based central server show that the data synchronization gateway constructed in this paper, works correctly.

• The KIPS Transactions:PartA
• /
• v.11A no.1
• /
• pp.37-48
• /
• 2004

The SyncML, the standard synchronization protocol, supports the synchronization of various application services between a client and a server such as an address book, a calendar. Even with this standard protocol, SyncML application developers usually spend a long time and efforts implementing service specific logics and databases. This paper designed and implemented the SDE(Service Development Environment) which is an integrated development environment for SyncML server developers to develop an application service rapidly and correctly. The SDE consists of two components i.e., the Sync Library and the SEG(Sync Engine Generator) tool. To prove the applicability of this study we implemented a SyncML server by using the SDE and also carried out the correctness tests and the performance test. We hope this system helps developers implement mobile application services more efficiently.

• Journal of KIISE:Computing Practices and Letters
• /
• v.14 no.2
• /
• pp.117-129
• /
• 2008

Data synchronization between data stored in mobile communication terminals and data in a central server is one of essential tasks for efficient mobile communication environments. Since, however, manufacturers of mobile terminals have their proprietary data synchronization mechanisms, data interoperability can hardly be achieved. In this paper, an integrated data synchronization gateway based SyncML is designed and implemented. SyncML data synchronization is one of open standards proposed by OMA(Open Motile Alliance). In other words, by constructing a data synchronization gateway which can transform various proprietary data into SyncML data and vice versa, data interoperability between mobile terminals which use different data synchronization mechanisms can be achieved. With an integrated data synchronization gateway system implemented in this work, interoperability among WinCE-based ActiveSync data, PalmOs-based HotSync data and OMA SyncML data can be achieved.

• Proceedings of the Korean Information Science Society Conference
• /
• 2001.10c
• /
• pp.580-582
• /
• 2001

유무선 단말간의 데이터 동기화를 위한 표준인 SyncML을 이용하여 SyncML서버를 구현하였다. SyncML의 개략적인 설명과 함께 구현한 SyncML 서버 구조를 소개하고, 그 중 Sync Engine에 대하여 기술하였다. Sync Engine은 SyncML 프로토콜에 영향을 주지 않고 제공되어지는 서비스 및 정책에 종속적인 역할을 담당하는 프레임이다. Sync Engine을 구현함으로써 사용자에게는 편리하게 다양한 서비스를 사용할 수 있고, 개발자에게는 쉽고 빠르게 서비스의 추가 및 정책 반영을 합 수 있다.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.58 no.7
• /
• pp.1255-1262
• /
• 2009

The present study explained the phenomenon that low frequency oscillation is synchronized with discrete data obtained from a wide area system, and a sync search method. When a disturbance occurs in an power system, various controllers operate in order to maintain synchronization. If the system's damping is poor, low frequency oscillations continue for a long time and the oscillations are synchronized with one another at specific frequency. The present study estimated dominant modes, magnitude and phase of signals by applying parameter estimation methods to discrete signals obtained from an power system, and performed sync search among wide area signals by comparing the estimated data. Sync search was performed by selecting those with the same frequency and damping constant from dominant oscillation modes included in a large number of signals, and comparing their magnitude and phase. In addition, we defined sync indexes in order to indicate the degree of sync between areas in a wide area system. Furthermore, we proposed a wide area sync search method by normalizing mode magnitude in discrete data obtained from critical generator of the wide area. By applying the sync search method and sync indexes proposed in this study to two area systems, we demonstrated that sync scanning can be performed for discrete signals obtained from power systems.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.55 no.4
• /
• pp.163-171
• /
• 2006

This paper presents a definition of sync phenomenon occurring in power systems, and describes the characteristics of sync in basic electric circuits. In addition, sync observed in basic circuits was extended to the analysis of dynamic characteristics in power systems. This paper, moreover, describes the sync occurring among system outputs from time domain simulation for two-area systems. In power systems, sync is a common phenomenon that is always observed among generator powers or bus voltages. Thus, we can use sync to obtain the characteristics of power systems without being bound to a specific operating point. Sync can be useful information in power system operation and planning.

• Journal of Korea Multimedia Society
• /
• v.8 no.9
• /
• pp.1153-1162
• /
• 2005

In this paper, we developed an XML Document Data Synchronization System for java(XDS4j) based on both SyncML(Synchronization Markup Language) framework Sync4j and embedded database system Berkeley DB XML. Because most existing data synchronization systems are based on file systems, data synchronization times at Fast Sync in those systems are very delayed. In the XDS4j, however, XML documents data produced at SyncML client and SyncML server are managed by embedded database system, and also synchronization time at Fast Sync is reduced because only partial elements are accessed by applying to XPath.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.24 no.6
• /
• pp.992-997
• /
• 1987

This paper describes the design and fabrication of an integrated circuit that can separate the horizontal SYNC., vertical SYNC. and composite SYNC. signal included in a composite video signal. The circuit that is based on the comparator level samplign method can separate a stable SYNC. signal even from an external circuit with large variation. It has been fabrivated by the SST bipolar process. Its chip size is 1.5x1.5mm\ulcorner As a result, we succeeded in fabrication of IC which satisfied DC characteristics and SYNC. singal separator function.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.14 no.5
• /
• pp.472-485
• /
• 1989

This paper represents the occurrence structure of the timing variation of TV horizontal synchronizing pulse(H-sync pulse) in mobile TV reception. Fluttering ghost is caused by timing varations of the H-sync pulse and is due to frequency elective fading in a multipath propagation envoronment. H-sync timing fluctuations, and hence, fluttering ghost are directly correlated with the multipath parameters, i.e., H-sync timing fluctuations reflect well the severity of the multipath environment. The occurrence structure of H-sync timtng fluctuation is analysed theoretically in relation to the multipath environnment. The occurrence structure of H-sync timing fluctuation is analysed theoretically in relation to the multipath parameters, assuming the two-ray propagation model. The H-sync timing fluctuation occurs with the variation in relative phase and /or D/U variation of long-delayed multipath waves.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2002.11a
• /
• pp.175-178
• /
• 2002

모바일 인터넷 환경에서 동일한 데이터가 다양한 단말 장치에 산재되어 사용되는 경우 효과적인 사용과 관리를 위해 산재된 데이터가 서로 동기화(synchronization) 즉 일치되어야 한다. SyncML은 모바일 인터넷 환경에서 다양한 플랫폼을 가진 기기 사이의 데이터 동기화를 위해 제시된 표준 프로토콜로서 많은 국 내외 산업체 및 연구기관이 SyncML 규격을 구현한 제품을 선보이고 있다. 이러한 SyncML 구현 제품이 이질적인 플랫폼에 상관없이 상호운용되기 위해서는 SyncML 규격에 대한 규격 준수 시험이 필요하다. 본 논문은 SyncML 규격의 적합성 시험(conformance test)을 위한 시험도구의 설계와 구현에 대하여 논한다.