• Proceedings of the Korea Contents Association Conference
• /
• 2006.11a
• /
• pp.469-473
• /
• 2006

Nowadays, to realize ubiquitous computing environment, many research activities have been going on within various kinds of research domains including automatic identification, sensor network, home network, telematics and so on. Especially, RFID middle-ware that supports the aggregation of RFID tag data, control and management, and the integration with legacy systems has recently gained a lot of attention. Meanwhile, EPCglobal defined an ALE(Application Level Events) standard specification, which exists between RFID readers and applications, and substitutes the previous systems called Savant. In the specification internal structures and implementation technologies of ALE are not mentioned and only external interfaces are defined. This approach easies the verification of standard compliance and inter-operability of the layer. In this paper, we present the design of ALE-compliant RFID middle-ware systems that process RFID tag data efficiently.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.40 no.10
• /
• pp.119-128
• /
• 2003

The rapid increase of Internet users, diversity of application services, high speed data transmission, and extension of application areas have resulted in exponential growth of Internet traffic. In order to satisfy the increasing demand of bandwidth, the MPλS protocol, which is based on MPLS for efficient integration of WDM and IP protocols, has been suggested by IETF. In this paper, we present an MPλS simulator which enables to simulate various MPλS function such as optical crossconnect (OXC), multi-wavelength links, routing and wavelength assignment(RWA), and MPλS signaling and control. The simulator is developed based on the ns-2, an widely used multi-protocol network simulator. The function of the simulator is validated by running many simulation based on various scenarios and performance measures such as throughput and blocking probability. The simulator could be widely utilized for validation of proposed protocols before developing real optical network systems.

• Journal of Internet Computing and Services
• /
• v.1 no.2
• /
• pp.11-18
• /
• 2000

In this paper we present a new extensible model based upon the concept of subtransactions in real-time transaction systems. The nested transaction model originally proposed by J. Moss is extended for real-time uniprocessor transaction systems by adding explicit timing constraints. Based upon the model, an integrated concurrency control and scheduling algorithm is developed, that not only guarantees timing constraints of a set of real-time transactions but also maintains consistency of the database. The algorithm is based on the priority ceiling protocol of Sha et al. We prove that the Real-Time Nested Priority Ceiling Protocol prevents unbounded blocking and deadlock, and maintains the serializability of a set of real-time transactions. We use the upper bound on the duration that a transaction can be blocked to show that it is possible to analyze the schedulability of a transaction set using rate-monotonic priority assignment. This work is viewed as a step toward multiprocessor and distributed real-time nested transaction systems. Also, it is possible to be extended to include the real-time multimedia transactions in the emerging web-based database application areas.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.23 no.5
• /
• pp.1397-1408
• /
• 1998

Service networks for the future communication networks will be combined by the B-ISDN networks. These service networks also will use SS No.7 as the signaling transport network for the control of user requriement service. Therefore, ITU-T recommended B-ISDN signaling layers for SS No.7 as a substitute for N-ISDN MTP signaling layer. In this paper, we propose the implementation structure and describe the characteristics and functions of each signaling layer of SS No.7, which are adapted to ATM switching system, and evaluate a performance. The structure of SSCOP transmission buffer using a linked list and an unit frame length is proposed for SAAL layer and the implementation structure and internal routing method according to the ATM switching system are also proposed for MTP-3b layer. Additionally, we propose the ISUP/B-ISUP level interworking structure using only associated mode, which are presented in the first stage of B-ISDN as the effective internatworking structure of SS No.7 for the circuit related signaling network between the existing N-ISDN networks and B-ISDN networks.

• Journal of Internet Computing and Services
• /
• v.6 no.3
• /
• pp.71-84
• /
• 2005

Recently, the expert call center solution has become the center of interest, since finance and tele-marketing system, which is focused on a communication industry, have been increasing, Specially, the call center market is growing up with a supporting Caller-ID for a cellular phone in Korea, In the present, although large size companies are developing expensive solutions and instruments to service only for the big companies, there little solutions for SOHO markets, Therefore, in this paper we have shown a design and an implementation of a CTI system which is capable of in/outbound call processing by using CTI, and providing stable services by linking the customer's DB. And these functionalities have become possible by integrating functions of PBX and the computer control of the PBX. First, we have constructed call flows and analyzed packets for the standard communication through the PBX in call. Then, we have designed and implemented a middleware which linked a call between a client and a customer. Finally, we have constructed a database module for applying the CRM technology to the management of customer's contents.

• Journal of Energy Engineering
• /
• v.19 no.2
• /
• pp.128-135
• /
• 2010

This paper introduces step by step procedures for the fabrication and operation of an embedded solar tracker. The system presented consists of application software, compactRIO, C-series interface module, analogue input module, step drive, step motor, feedback devices and other accessories to support its functional stability. CompactRIO that has a real-tim processor allows the solar tracker to be a stand-alone real time system which operates automatically without any external control. An astronomical method and an optical method were used for a high-precision solar tracker. CdS sensors are used to constantly generate feedback signals to the controller, which allow a solar tracker to track the sun even under adverse conditions. The database of solar position and sunrise and sunset time was compared with those of those of the Astronomical Applications Department of the U.S. Naval Observatory. The results presented here clearly demonstrate the high-accuracy of the present system in solar tracking, which are applicable to many existing solar systems.

• Journal of KIISE:Computer Systems and Theory
• /
• v.26 no.8
• /
• pp.930-938
• /
• 1999

미래의 통합 이동 통신망은 멀티미디어 데이터 서비스를 하기 위해 작은 셀로 망이 구성될 것이다. 셀이 작은 경우, 이동 호스트의 셀간 이동이 상대적으로 증가해서 잦은 핸드오프 처리로 서비스 중단이 빈번히 발생할 수 있을 뿐만 아니라 자원의 낭비도 많아지게 된다. 따라서 이런 문제를 해결하기 위해 이동 호스트의 이동성을 예측해서 멀티캐스트 연결을 구성해서 사전 핸드오프 처리를 하는 SGMH방법을 제안한다. SGMH방법의 성능 평가를 위해 핸드오프 처리과정의 데이터 및 제어 정보의 흐름을 분석하고, 망 종속 인자들을 도입해서 버퍼 오버헤드와 서비스 중단 시간 면에서 기존 핸드오프 방법들과 비교했다. 비교 분석한 결과는 제안한 방법이 기존의 방법보다 기지국에서의 버퍼 오버헤드뿐만 아니라 서비스 중단 시간을 줄일 수 있음을 보였다.Abstract For mobile multimedia data services, future mobile communication networks will consist of small cells. In case of smaller cell size, the number of user movements between cells will increase and more network resources will be consumed for processing frequent handoffs. This processing delay will cause frequent connection service disruptions. To solve these problems, a multicast-based handoff method ,called SGMH(Sub-Group Multicast-based Handoff), is suggested. SGMH method estimates future movements of mobile hosts and setups a dynamic multicast connection tree for procesing handoffs. For performance evaluation, we represent flows of data and control messages as timing diagrams and introduce several network related factors. In terms of buffer overhead and service disruption time we compared the SGMH method to other methods. The results show that SGMH method has better performance in that it can reduce consumption of network resources and minimize service disruption time.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.4
• /
• pp.739-746
• /
• 2016

The real-time railway safety monitoring and control system is for prevention of safety accidents, and this system adopts DDS (Data Distribution Service) standard based data transmission method to support integrated management of data from existing on-site safety detection devices. In this paper, we introduce the design of DDS-based data specification from on-site signal equipment on the conventional railway. For this, we (1) design UML data model of KRS SG 0062 standard which defines existing data specification, (2) define DDS Topics for DDS transmission and map KRS model to DDS Topic model, (3) suggest data transformation rules and (4) design network control QoS polices. In addition, we analysis actual on-site log data and validate our data specification design. DDS-based data transmission enables data compatibility among on-site devices and the real-time railway safety monitoring and control system, and allows efficient network management for a large amount of data transfer.

• Proceedings of the Korea Contents Association Conference
• /
• 2009.05a
• /
• pp.822-827
• /
• 2009

As research for URC robot to advance the robot system dissemination and pracical use becomes active, also interest for robot platform and standardization is increasing. However, URC robot middleware does not involve a convergence with IT. Although it seems to be a high connection between robots and IT, the existing middleware has not considered different environments, thus making convergence efforts difficult. The middleware should improve their functions in order to synchronize with IT and to interact through formatted messages. In this paper, we present the necessity of the formatted message in the development of URC platform. In addition, design of the message protocol for the convergence based on the analysis of RUPI, OPC and SECS-II.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.9
• /
• pp.1839-1846
• /
• 2012

With increasing chronic patients due to population aging, many needs for pro-active health and medical treatment services are rising and desire for health care service is also rising due to national standard of living Especially population aging of Korea is faster than America, France and many other advanced nations, and a study states that arrival time of elderly population rates; 14%(aged society) to 20%(transcendental aged society)l only takes 8 years. In these reasons, health care industry for the next engine industry is reinforced. Many health care terminals are coming out and Continua Health Alliance is founded and working steadily based on Philips in 2006. In this paper, we suggest Gateway interface system for Continua accreditation to control vary communication by designing intelligent health care interface suitable for Continua international accreditation because there are many types of terminals and communication protocols.