• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.6 no.6
• /
• pp.1496-1521
• /
• 2012

Uncertainty is ubiquitous in target tracking wireless sensor networks due to environmental noise, randomness of target mobility and other factors. Sensing results are always unreliable. This paper considers unreliability as it occurs in wireless sensor networks and its impact on target-tracking accuracy. Firstly, we map intersection pairwise sensors' uncertain boundaries, which divides the monitor area into faces. Each face has a unique signature vector. For each target localization, a sampling vector is built after multiple grouping samplings determine whether the RSS (Received Signal Strength) for a pairwise nodes' is ordinal or flipped. A Fault-Tolerant Target-Tracking (FTTT) strategy is proposed, which transforms the tracking problem into a vector matching process that increases the tracking flexibility and accuracy while reducing the influence of in-the-filed factors. In addition, a heuristic matching algorithm is introduced to reduce the computational complexity. The fault tolerance of FTTT is also discussed. An extension of FTTT is then proposed by quantifying the pairwise uncertainty to further enhance robustness. Results show FTTT is more flexible, more robust and more accurate than parallel approaches.

• The Journal of Korean Association of Computer Education
• /
• v.15 no.6
• /
• pp.75-82
• /
• 2012

The sensor registry system has been proposed to interpret and process semantics of sensor data independently of heterogeneous sensor networks. However, the existing sensor registry system provides the static processing method. In other words, the existing system reduces the overall performance because it executes unnecessary operations and does not consider data scope to be used. To resolve the problem of the existing sensor registry system, this paper proposes a performance enhancement model based on sensor metadata reusability and scoping. The proposed model in this paper provides a function that can decide a proper scope of sensor metadata from the sensor registry system. The proposed model improves the overall performance by providing reusability of sensor metadata. This paper also shows the advantages of the proposed model through the comparative performance evaluation.

• Journal of Advanced Navigation Technology
• /
• v.11 no.4
• /
• pp.461-472
• /
• 2007

In Ubiquitous Sensor Network (USN), the sensor nodes are required to consume their energy evenly to prolong the lifetime of the entire sensor network because of the limited energy of the sensor node. AODV which is applied to USN as routing protocol selects route according to only the shortest distance of the minimum hop count but regardless of the remaining battery power for each node. Thus it comes to ill-balanced power consumption seriously. In this paper, a scheme that controls packet relay quantity of each sensor node adaptively to prevent traffic overhead at a certain node and to increase the entire network lifetime is proposed. As it is analyzed by simulations, the proposed scheme enhances USN lifetime by balancing each sensor node's packet relay quantity.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.5B
• /
• pp.816-823
• /
• 2010

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.

• Fire Science and Engineering
• /
• v.25 no.2
• /
• pp.39-46
• /
• 2011

In correctional facilities with majority of occupants in custody, the safe evacuation guide without getaway accidents should be very important due to complexity in escape paths. Fire causes are various in correctional facilities, for example, arson fire is a major cause in mental treatment facilities, however, old facilities or carelessness of flammable materials consist of fire causes in jail facilities. Both types of correctional facilities are the same in terms of many casualties from the fire cases. The thesis focus on escape paths and evacuation guide plans on the basis of analysis on fire cases and structural vulnerability, and then an electronic unlocking system is concededly installed for safe evacuation of occupants in custody without getaway accidents. Especially, the effect of the electronic unlocking system is going to be analyzed on the basis of RSET (required safe egress time) in order to realize for the occupants to evacuate safely to the front yard in case of emergency. In conclusion, if electronic security allowed system with USN (Ubiquitous Sensor Networks) technology should be installed in multi-storey correctional buildings, it is proposed that the occupants in custody might be a guided safely without getaway trials.

• International journal of advanced smart convergence
• /
• v.5 no.1
• /
• pp.1-7
• /
• 2016

Recently, introduced a cloud computing technology to the IT industry, smart phones, it has become possible connection between mobility terminal such as a tablet PC. For dissemination and popularization of movable wireless terminal, the same operation have focused on a viable mobile cloud in various terminal. Also, it evolved Wireless Sensor Network(WSN) technology, utilizing a Body Sensor Network(BSN), which research is underway to build large Ubiquitous Sensor Network(USN). BSN is based on large-scale sensor networks, it integrates the state information of the patient's body, it has been the need to build a managed system. Also, by transferring the acquired sensor information to HIS(Hospital Information System), there is a need to frequently monitor the condition of the patient. Therefore, In this paper, possible sensor information exchange between terminals in a mobile cloud environment, by integrating the data obtained by the body sensor HIS and interoperable data DBaaS (DataBase as a Service) it will provide a base of mBodyCloud System. Therefore, to provide an integrated protocol to include the sensor data to a standard HL7(Health Level7) medical information data.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.7
• /
• pp.1721-1726
• /
• 2014

The sensor network technology for core technology of ubiquitous computing is in the spotlight recently, the research on sensor network is proceeding actively which is composed many different sensor node. The major traffic patterns of plenty of sensor networks are composed of collecting types of single directional data, which is transmitting packets from several sensor nodes to sink node. One of the important condition for design of sensor node is to extend for network life which is to minimize power-consumption under the limited resources of sensor network. In this paper analysis used routing protocols using the network simulation that was used second level cluster structure to reduce delay and power-consumption of sensor node.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.48 no.4
• /
• pp.43-50
• /
• 2011

Sensor networks are expected to play key roles in establishment of fundamental infrastructures, information collection, and devices control to provide services for ubiquitous society in the near future, where recent issues include energy efficient energy supply scheme in the sensor network based systems has been getting more attention. This paper formulates an energy supply problem that minimizes the total energy supplied to clustered sensor networks while maintaining the network lifetime. An energy supply scheme is suggested that determines the the amount of engergy supply to each cluster head based on the solution of the problem. Simulation results show that the proposed scheme achieves better energy efficiency compared with a simple scheme of maximum possible energy supply to each cluster head.

• Journal of Internet Computing and Services
• /
• v.10 no.5
• /
• pp.13-26
• /
• 2009

Wireless Sensor Networks (WSNs) is one of the key technologies that make it possible to provide u-service in a ubiquitous society, however, it has disadvantages such as difficulty of managing sensor nodes and weaknesses of stability or mobility in large-scale WSNs. In order to solve these problems, 6LoWPAN that integrates with WSNs and IP networks has been studied widely. In this paper, we propose a Location Tracking Service Based on Google Map (LTSGM) system using 6LoWPAN. Since LTSGM system provides visual location information of sensor nodes through Google Map, it is possible to makes it easier than ever to manage sensor nodes in large-scale WSNs. Moreover, LTSGM can be used for various services such as applications for disaster or crime because it can trace the location of mobile nodes. Implementation of LTSGM system will be a test platform for 6LoWPAN.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.10a
• /
• pp.1022-1025
• /
• 2009

USN(Ubiquitous Sensor Network) is a core infrastructure that makes come true the u-life in the ubiquitous society through various services of area such as u-city and u-Health. Therefore, we need to reseach about the domestic standards to establish the core technique of USN. Currently, the status of USN standards is most of technical standard and reseach that are technology for sensor node implementation and a protocol for energy-efficient communication and interlock with existing network. But, Standard and reseach for sensor network, integration management of heterogeneous sensor networks for USN application, sensing data management and USN database structure definition such as application and middleware are weak level. In this paper, we researched for standard development of the domestic sensor network service and relevant standard analysis to configure SWE(Sensor Web Enablement) of OGC(Open Geospatial Consortium) for standarded plattform technoloy in part of the middleware. Also we researched that it's a connection between domestic TTA (Telecommunications Technology Association) standards and SWE Standard. Finally, we researched for standard service plattform architecture on sensor network through analysis on the possibility of applying OGC-based services platform.