• Journal of KIISE:Computing Practices and Letters
• /
• v.12 no.1
• /
• pp.31-42
• /
• 2006

Context-awareness is a technology to facilitate information acquisition and execution by supporting interoperability between users and devices based on users' context. It is one of the most important technologies in ubiquitous computing. In this paper, we propose a middleware and a context server for dealing with context-awareness in ubiquitous Computing and implement an application system using them. The middleware proposed in our work plays an important role in recognizing a moving node with mobility by using a Bluetooth wireless communication technology as well as in executing an appropriate execution module according to the context acquired from a context server. In addition, the proposed context server functions as a manager that efficiently stores into a database server context information, such as user's current status, physical environment, and resources of a computing system. Finally, our application system implemented in our work one which provides a music playing service based on context information, and it verifies the usefulness of both the middleware and the context server developed in our work.

• Journal of the Korea Convergence Society
• /
• v.8 no.3
• /
• pp.115-121
• /
• 2017

Hospital medical services are making great efforts to provide prompt medical services to patients or improve the quality of medical services by convergence patient's healthcare information. However, recent research suggests problems about safety and efficiency when trying to transmit patient's healthcare information to hospital server via radio and wireless. In this paper, we propose a color model - based patient authentication key establishment protocol method to securely transmit patient healthcare information. The proposed method extracts randomly three color information used in the color model and vectorizes the extracted arbitrary information to obtain the key information required for user authentication as the sum of orthogonal vectors to improve the efficiency. In addition, the proposed method can securely generate key information used for user authentication without using an additional encryption algorithm. In performance evaluation result, proposed method shows that the server processing time of the sensed information is 8.1% higher than the existing method and 7.7% lower than the existing method.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.3
• /
• pp.719-724
• /
• 2011

Most recent birth rate at home raising children, only one has come out well. Accordingly, children born to parents is to have a strong interest, and healthcare (Healthcare) sector, while emerging as a new growth industry (Baby Care) Baby Care also increased the interest. Baby Care products until now the food, toiletries and clothing, etc. Although it advances the development of ubiquitous computing environment with the development of the healthcare industry, Baby Care Electronics products have been developed. Europe and the U.S. infant from another room deungeseoneun feeder. At this time SIDS infants to prevent this phenomenon often takes place in order to measure the status of children and away from parents to children, also can check the status of children was used to implement the Platform. In this paper, using the radio frequency real-time observation of data storage without the parents were determined only by the speed of the ARM11-based systems using the S3C6410 CPU and wireless WI-FI (IEEE8.2.11) technology to prevent sudden infant death using Platform for the implementation study was conducted.

• The KIPS Transactions:PartD
• /
• v.8D no.3
• /
• pp.221-232
• /
• 2001

Due to rapid advance of wireless communication technology, demand on data services in mobile environment is gradually increasing. Caching at a mobile client could reduce bandwidth consumption and query response time, and yet a mobile client must maintain cache consistency. It could be efficient for the server to broadcast a periodic cache invalidation report for cache consistency in a cell. In case that long period of disconnection prevents a mobile client from checking validity of its cache based solely on the invalidation report received, the mobile client could request the server to check cache validity. In doing so, some schemes may be more efficient than others depending on the number of available channels and the mobile clients involved. In this paper, we propose new cache consistency schemes, effects, efficient especially (1) when channel capacity is enough to deal with the mobile clients involved or (2) when that is not the case, and evaluate their performance.

• Journal of the Korea Society of Computer and Information
• /
• v.12 no.4
• /
• pp.69-75
• /
• 2007

On the wireless communication between RFID Tag and Reader, there are some existing problems with weaknesses of security such as spoofing, replay, traffic analysis, position tracking, etc., in the established hash lock related algorithm. This paper has presented the comparison and analysis of the established hash lock related algorithm for privacy and in order to make up for this, also suggested a new security authentication algorithm based on hash which has an authentication protocol and creates hash function by using random numbers received from the reader on real time and every session. The algorithm suggested here can offer a several of usefulness for RFID authentication system and it has an advantage to reduce the amount of calculations compared to established algorithm. It also uses the tags needed among a lot of tags around which are expected later and it is expected to reduce a responsibility of the server by ending unnecessary tags' operation with time based.

• Journal of the Korea Society of Computer and Information
• /
• v.12 no.5
• /
• pp.83-92
• /
• 2007

In this paper, we present a design and implementation of three dimensional pointing device using Inertial Navigation System(INS) that acquires coordinates and location information without environmental dependancy. The INS measures coordinates based on the data from gyroscope and accelerometer and corrects the measured data from accelerometer using Kalman-Filter. In order to implement the idea of three dimensional pointing device, we choose a three dimensional Space-recognition mouse and use RFIC wireless communication to send a measured data to receiver for printing out the coordinate on display equipment. Based on INS and Kalman-Filter theoretical knowledge, we design and implement a three dimensional pointing device and verified the usability as an input device that can capture a human's move. also, we describe the applicability of this device in ubiquitous computing environment.

• Journal of the Korea Society of Computer and Information
• /
• v.10 no.4 s.36
• /
• pp.29-36
• /
• 2005

As computing environments are more rapidly developed, an adaptive and intelligent services using post PC such as PDA. Laptop, and Tablet PC in case of rounding and examining patients are highly demanded. The objective of this study is to design and implement a context-awareness support system based on voice service for medical environments. To achieve it, we propose a context middleware which plays an important role in recognizing a client with PDA by using a Bluetooth wireless communication technology as well as in executing an appropriate execution module, like delivery for diagnosis information of patients, according to the staff's context acquired from a context server. In addition, the context server functions as a manager that efficiently stores context information such as client's current status, physical environment, and device resources into a database server. Finally, for verifying the usefulness of the proposed system, we develop an application system which provides voice playing services for notification of other physicians through our context middleware.

• Convergence Security Journal
• /
• v.13 no.4
• /
• pp.11-17
• /
• 2013

All u-Health system has security vulnerabilities. This vulnerability locally(local) or network(network) is on the potential risk. Smart environment of health information technology, Ad-hoc networking, wireless communication environments, u-health are major factor to increase the security vulnerability. u-health care information systems user terminal domain interval, interval public network infrastructure, networking section, the intranet are divided into sections. Health information systems by separating domain specific reason to assess vulnerability vulnerability countermeasure for each domain are different. u-Healthcare System 5 layers of security risk assessment system for domain-specific security vulnerability diagnosis system designed to take the security measures are needed. If you use this proposed model that has been conducted so far vaguely USN-based health information network security vulnerabilities diagnostic measures can be done more systematically provide a model.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.41 no.6
• /
• pp.631-639
• /
• 2016

Wi-Fi Direct standard technology has been widely deployed on the recently manufactured products such as smart phone, smart monitor, TV, set-top box, and gaming console, and it was published from Wi-Fi Alliance with the name of Wi-Fi Peer-to-Peer Technical Specifications (v1.4, 2014) for direct connection on the wireless communication environment. However, the connection process of this standard needs 5 to 10 seconds so it can lead to user's inconvenience as well as long delay for connection. From the focus of that this problem was derived from long discovery process composed of Scan and Find, as a result, the proposed scheme on this paper modified and adapted Scan and Find processes with reassembling steps of them for reducing the connection delay. In addition, the analysis and experiments were progressed for the evaluations of the proposed scheme.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38C no.1
• /
• pp.97-108
• /
• 2013

Recently, mobile devices were increased and there was a sharp rise in demand. To exploit the location information of each device, many researcher was studying locating systems. The favorite locating or positioning systems were a GPS using satellites and a RTLS using wireless communication between devices. If some obstacle existed nearby the target device, The system have difference of performance. The obstacles near targets were caused signal disconnection and reflection because of NLOS condition. As the result, the NLOS condition degrade the locating performance. In this paper, we propose a locating system which is cooperated two systems using information reliability estimates from LOS/NLOS condition. We developed proposed system. In addition, we performed fields test and simulation tests at various environment for performance evaluation. As the result, the test showed 97% success rate to estimate NLOS condition. Furthermore, the simulation result of our locating system was increased to 89% compared with a single system.