• The KIPS Transactions:PartD
• /
• v.15D no.2
• /
• pp.263-270
• /
• 2008

Research of ubiquitous computing becomes more popular topic along with the rapid development of wireless technologies. Firstly, research and development on RFID focuses on manufacturing and retail sectors, because it can improve supply chain efficiency. But, it changes to USN (Ubiquitous Sensor Network) by adding a sensor and wireless network technologies on it. In this research, we design and implement the electric facility management service framework to collect real time information of electric facility using RFID/USN. In electric power industry, it is important the supply of energy must be guaranteed. So many power utilities control and supervise the transmission line to avoid power failures. Utilities install many types of sensor to monitor important facilities by wired network such as optical cable and PLC. In this research, we develop the sensor node which is small, easy to install and using wired network. We design the service framework for electric facility management to collect data using RFID tag, reader and wireless sensor nodes and implement the electric facility management service.

• 한국IT서비스학회:학술대회논문집
• /
• 2007.05a
• /
• pp.341-346
• /
• 2007

최근 유비쿼터스 환경에서 센서 네트워크를 이용한 여러 가지 연구가 활발히 진행되고 있다. 향후 USN 인프라 구축이 완료됨에 따라 USN을 활용하기 위한 USN 어플리케이션 개발을 보다 손쉽게 하기 위해 USN 미들웨어(USN Middleware)의 필요성이 대두되며, 디렉토리 서비스(Directory Service)는 USN 미들웨어를 구성하는 핵심 서비스 중의 하나이다. USN 인프라가 인터넷과 결합된 USN 환경에서의 디렉토리 서비스는 USN 계층의 자원에 대한 개별적인 속성을 돌려 줄 수 있어야 한다. 그러나 풍부한 컴퓨팅 자원, 높은 대역폭(bandwidth) 및 짧은 지연시간, 멀티캐스트 기능 등을 가지고 있는 인터넷과 달리 USN을 구성요소인 WSN(Wireless Sensor Network)은 제한된 컴퓨팅 자원, 에너지 문제, 낮은 대역폭, 무선 통신의 불안정성 등의 특성을 가지고 있다. 이러한 이유로 디렉토리 서비스 기술은 WSN에 직접 적용하기가 어렵다. 본 논문에서는 기존의 디렉토리 서비스에서 나타날 수 있는 문제와 WSN의 특성을 고려하여 USN 인프라에 적합한 USN 디렉토리 서비스 (Ubiquitous sensor network Directory Service: UDS)를 설계 및 구현한다.

• Proceedings of the KAIS Fall Conference
• /
• 2011.12b
• /
• pp.529-532
• /
• 2011

Recently research efforts for ubiquitous technology that includes RFID(Radio Frequency Deification and sensor networks are conducted very actively The architectural framework of the USN sensor network discovery service. The survey of the USN technology is conducted on four technological visions that contain USN system technology USN networking technology and USN middleware along with the service platform, With respect to each technological division domestic and worldwide leading research projects are primarily explored with their technical features and research projects are primarily explored with their technical features and research outputs. Boasted on the result of the survey we establish a USN software model that includes data sensing, sensor data storage sensor data storage sensor data naming and sensor feed name service. This main objective of this model is to provide a reference model for the facilitation of USN application developments.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.10
• /
• pp.137-145
• /
• 2010

This paper is proposed non-contact plant growth measurement system using infrared sensor based on USN(Ubiquitous Sensor Network) technologies. The proposed system has used noncontact sensors to reduce any potential damage when it measures the growth of the plant. In this system, plant growth parameters such as diameter, cross-sectional area and thickening form are measured in real-time non-contact method. The measured data are transmitted to remote server by using sensor network technologies, stored and analyzed at the server, and the analyzed data are finally provided for users. In this paper, the proposed plant growth measurement system has been designed and implemented using non-contact infrared sensor based measurement methods and devices, and its performances have been verified by actual measurement experiments at the fields.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• v.9 no.2
• /
• pp.1027-1030
• /
• 2005

The article introduces developing trends of an adaptive mobile terminal as an interface for use of various network resources, such as public wireless networks and un-licensed wireless networks in ubiquitous sensor network environments, without troublesome settings or operations by users. These adaptive mobile terminals able to provide seamless services that adapt autonomously to the user's movements and changes in the state of wireless resources. Consequently, adaptive mobile terminals should be had respective independent hardware structure of usable wireless networks.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.12B
• /
• pp.1426-1434
• /
• 2009

RFID/USN is considered as a key convergence technology in future ubiquitous network. In RFID/USN, the power saving issue receives a great attention due to limited battery lifetime of sensor node. In this paper, we propose a new power saving algorithm, which takes advantage of long-term sleep period. To provide a full network connectivity and balance the battery consumption among sensor nodes, the proposed algorithm intelligently selects the long-term sleep sensor nodes. With mathematical analysis and simulations, we prove that the proposed algorithm can significantly reduce the power consumption of sensor nodes as compared to existing algorithms.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.12
• /
• pp.151-162
• /
• 2010

In order to build up the ubiquitous computer environment, there are many researches on automatic identification, sensor networks, and home networks etc. EPCIS (EPC Information Services), which is proposed by EPCglobal, is a standard on the repository managing tag data that is needed to develop RFID application system. In this paper, the EPCIS repository is designed and implemented. It is able to search the object dependent upon general object recognition and environment information variation. And sensor data, which is also massive data and is changed with position, is integrated into RFID data in the system. By doing so, it is possible to do the convergence managements of object recognition with variations of USN (Ubiquitous Sensor Network) environment.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.10 no.5
• /
• pp.293-298
• /
• 2010

The key of USN(Ubiquitous Sensor Network) technology is low power wireless communication technology and proper resource allocation technology for efficient routing. The distinguished resource allocation method is needed for efficient routing in sensor network. To solve this problems, we propose an algorithm that can be adopted in USN with making up for weak points of PQ and WRR in this paper. The proposed algorithm produces the control discipline by the fuzzy theory to dynamically assign the weight of WRR scheduler with checking the Queue status of each class in sensor network. From simulation results, the proposed algorithm improves the packet loss rate of the EF class traffic to 6.5% by comparison with WRR scheduling method and that of the AF4 class traffic to 45% by comparison with PQ scheduling method.

• 한국ITS학회:학술대회논문집
• /
• v.2007 no.10
• /
• pp.208-213
• /
• 2007

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.5
• /
• pp.948-955
• /
• 2008

Recently, as the dissemination of the Internet and development of computer network technology, Research is actively underway for realization of the next-generation computing paradigm called Ubiquitous Computing. For realization of Ubiquitous computing, The data recognized from each sensors must be collected on real-time and transferred to applied service so that they may be used as data for providing service to users. However, there are several problem for realization. First, there is no standardization of sensor metadata, interface and event definition. Second, applied service has weak point that difficult of approaching to the data. Third, none interoperability with each platform and protocol. In this paper, we designed Sensor Service Description Language based on XML to resolve problem above. This Language expresses the measurement of the sensor and Service Metadata in the form to be standardized. In addition, we have proposed and development a reference model for USN application service.