• The Journal of the Korea institute of electronic communication sciences
• /
• v.5 no.2
• /
• pp.221-226
• /
• 2010

Ubiquitous computing is technology that provides services appropriate for the user. At places where environmental and situational context are relevant in making the determination of what services are appropriate, there are sensor nodes installed, which automatically collect, manage and control environmental information. In this computing environment, in order to meet the requirements of services provided to users, a context awareness system is needed for context awareness processing. In this thesis, using RFID/USN sensors, the context of a user entering and leaving an area was produced, and the user's identification information was received via the RFID reader and antenna. At the same time, to decide whether or not to allow access for the user, a distance sensor node was installed to collect context data. Based on this, a system that provides practical services needed in real life for users was designed and implemented. The context of a user entering an area was produced, which the system recognized and provided appropriate services for the user.

• Proceedings of the Korea Society of Design Studies Conference
• /
• 2001.10a
• /
• pp.52.1-52
• /
• 2001

• Journal of Digital Contents Society
• /
• v.10 no.3
• /
• pp.469-477
• /
• 2009

This study is about Augmentative and Alternative Communication as handicapped people actively pursue their life. Especially, although there are many ways and devices for communicating the same as a normal person, descriptive supplementation and sustaining studies are needed for perfect communication as a normal person. The purpose of the paper is to help handicapped people who have hardships about communication. This study develops the function of Smart Workflow AAC(Augmentative and Alternative Communication) and IR sensor_based context aware function that can offer services convenient to classified handicapped people for helping them to communicate effectively. This system from an experimental basis has improved efficiency to communicate more harmoniously within individual handicapped situations to schedule management and communication of handicapped people.

• Proceedings of the Acoustical Society of Korea Conference
• /
• 1994.06a
• /
• pp.1027-1032
• /
• 1994

This paper introduces a interword modeling and a Viterbi search method for continuous speech recognition. We also describe a development of a real-time voice dialing system which can recognize around one hundred words and continuous digits in speaker independent mode. For continuous digit recognition, between-word units have been proposed to provide a more precise representation of word junctures. The best path in HMM is found by the Viterbi search algorithm, from which digit sequences are recognized. The simulation results show that a interword modeling using the context-dependent between-word units provide better recognition rates than a pause modeling using the context-independent pause unit. The voice dialing system is implemented on a DSP board with a telephone interface plugged in an IBM PC AT/486.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2006.07a
• /
• pp.369-369
• /
• 2006

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.10a
• /
• pp.453-456
• /
• 2007

In this paper, we describes a design of Wireless Mesh Network based middleware that applied into USN(Ubiquitous Sensor Networks). WMN based middleware is a technique which links data between widely distributed sensor devices and WMN for context-awareness. The use of WMN base middleware in this paper makes possible communication on insufficiently network constructed area by use of WMN. WMN based middleware also anaylze events comprehensively that originated from specific sensor device. Based on the result from analyzed data with predetermined value WMN based middleware will given an order to designated actuator devices. Middleware operate each function of sensor network management and application service separately.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.10 no.6
• /
• pp.169-177
• /
• 2010

A railroad is used to a lot of area and it is an eco-friendly and an effective means of communication which is a transport for passengers and products. In recent years, the accidents caused by subway and railroad are cognate with people. We need to come up with preparing measures to avoid the accidents. In this paper, to prevent an accident developing and implementing a system which is a railroad management safety system is the purpose. The system is able to provide scalability for smart railroad safety service based on context aware information. Besides, it is able to furnish flexibility through the OSGi framework.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.46 no.2
• /
• pp.81-88
• /
• 2009

This paper proposed a session key exchange and authentication scheme on non-interactive key distribution algorithm using a community member's ID in ubiquitous networks. In ubiquitous network environment, User's context-awareness information is collected and used to provide a context-awareness service for someone who need it. However, in ubiquitous network environment, this kind of the Context-awareness information could be abused by a malicious nodes. The proposed scheme using the community member ID provides a session key exchange and mutual authentication between community members, and supports secure data communication. Also, when exchanging the session key and authenticating each other, this scheme reduces communication overhead and authentication delay compared to the AAA server scheme.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.3
• /
• pp.465-470
• /
• 2013

Dempster-Shafer Evidence Theory is available for multi-sensor data fusion. Basic Probability Assignment is essential for multi-sensor data fusion using Dempster-Shafer Theory. In this paper, we proposed a novel method of BPA calculation with signal assessment. We took notice of the signal that reported from the sensor mote at the time slot. We assessed the variation rate of the reported signal from the terminal. The trend of variation implies significant component of the context. We calculated the variation rate of signal for reveal the relation of the variation and the context. We could reach context inference with BPA that calculated with the variation rate of signal.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.13 no.1
• /
• pp.35-40
• /
• 2013

The messages on mobile terminal may contain context information such as user's location, time and preference. This paper proposes message forwarding system based on user's context. The server stores the predefined target addresses which may be mobile phone number, web server address and email address. On request for message transmission, the server tries to find a target address matching a user's context. Thus, a sender transmits messages to a representative address without knowing various receiver's addresses and a receiver can retrieve classified messages according to subject/location.