• Journal of Institute of Control, Robotics and Systems
• /
• v.10 no.11
• /
• pp.1022-1027
• /
• 2004

In this paper, an embedded foot pressure measurement system is proposed to measure foot pressure based on the embedded Linux system. To measure foot pressure data and to evaluate foot pressure distribution for the different insoles, FSR sensor, A/D converter, iPAQ PDA, and a time division measurement method are employed in the system. Utilizing this system, the foot pressure analysis has been performed for the different four shoes. The number of foot pressure/voltage conversion circuits are drastically decreased by the proposed time division measurement method from 406 to 14. The experimental results for the sandal, slipper, oxford shoes and sneakers demonstrate that the proposed system successfully performs the foot pressure measurement.

• Annual Conference of KIPS
• /
• 2002.04b
• /
• pp.1349-1352
• /
• 2002

Handset 을 통한 m-Commerce 시장의 확장과 더불어 커머스를 기반으로 한 물류서비스, 무선 인트라넷, 모바일 증권거래 등에 PDA(Personal Digital Assistant)를 정보단말로 이용하는 서비스가 늘어나면서 PDA 무선 보안솔루션 개발에 관련된 관심이 잇따르고 있다. 특히 PDA 무선 보안솔루션은 무선 PKI를 비롯해 암호화 솔루션, 백신, 파이어월 등 다양한 분야에서 독특한 기술이 개발되고 있으며 보안분야의 새로운 시장을 형성할 것으로 기대된다. PDA 무선 보안 솔루션은 증권, 뱅킹 등에서 시도되어지고 있는 Application layer 에서 암호/복호화 하는 방식, 유선과 동일하게 브라우저/ 웹서버에서 제공하는 SSL 암호화 방식, SSL v3 및 TLS v1 과 호환되는 자체 암호화 모듈 방식등의 3 가지로 크게 나누어 볼 수 있다. 본 논문에서는 WinCE OS 의 iPaq PDA 에 SSL v3 및 TLS v1 과 호환되는 자체 암호화 모듈 방식의 시스템을 설계한다. PDA 와 서버 간의 인증, 메시지 기밀성 및 무결성을 충족시킬 수 있는 보안 서비스를 제공하고 유선과 동일한 수준의 보안 수준을 유지하면서도 지금까지 무선 암호인증의 문제점이었던 소용량 무선단말기의 한계를 극복하는 PDA 용 무선 보안 솔루션을 설계하는데 목적을 두고 있다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.4C
• /
• pp.570-580
• /
• 2004

Due to development of internet and mobile communication, M-commerce applications that utilize the digital signature are widely used these days. The mobile environment is weaker than the wired internet environment. Thus, it is highly required to systematically analyze the effect of processing the digital document and the digital signature algorithm, and low bandwidth of the mobile network on the system performance. In this paper, we have constructed the mobile contract system which has the XML based digital contract and the RSA signature algorithm as the test system. And we have derived the performance parameters and then measured in detail the runtime performance of the mobile digital signature system with the Compaq iPAQ 3850 PDA and CDMA 2000 1x mobile network.

• Proceedings of the Korean Information Science Society Conference
• /
• 2006.06d
• /
• pp.82-84
• /
• 2006

WebDAV는 IETF 표준으로서 웹상에서 분산 저작을 지원하도록 HTTP를 확장한 프로토콜이다. WebDAV 클라이언트는 WebDAV 프로토콜을 이용하여 WebDAV 서버자원을 관리하는 도구이다. 현재 WebDAV 기반의 자원 관리가 널리 사용되면서 무선 네트워크 환경에서 동작하는 클라이언트의 필요성이 증대되고 있다. 본 논문에서는 무선 네트워크를 지원하는 PDA에서 동작하는 WebDAV 클라이언트의 구현에 대하여 기술한다. 개발된 클라이언트는 간결한 사용자 인터페이스를 제공하며 WebDAV의 기본 메소드를 지원한다. 사용자는 인터페이스와 기본 메소드를 이용하여 WebDAV 서버에 자원을 등록하고, 서버 자원에 대한 열람, 검색, 이동 및 삭제를 할 수 있으며, 서버 자원을 내려 받을 수 있다. 본 클라이언트는 PDA에서 동작하기 위해서 .NET Compact Framework를 기반으로 구현 하였으며 관련 에뮬레이터를 이용하여 실험하였고 이를 실제 PDA장치인 'HP iPAQ hx2700'에 이식하여 검증하였다.

• The KIPS Transactions:PartA
• /
• v.10A no.5
• /
• pp.479-486
• /
• 2003

As the Internet appliances like digital TV, Internet set-top boxes, and Internet phone, are showing up in the market, the economics of real-time operating system (RTOS), which is an essential for controlling those devices, is expanding faster than ever before. ETRI has developed describes RTOS called Qplus-P, targeting various platforms ranging from PDA to Internet set-top box and home server. This paper describes the implementation of graphic window library for Qplus-P. The Qplus-P graphic window library was implemented using tiny-X graphic server and gtk graphic toolkit, which are open source software. To port this library to various aliances, hangul processing, screen rotation, touch screen, and graphic acceleration functions are added to the tiny-X graphic server of the implementd graphic window library. Currently, Qplus-P graphic window is running on ARM-based appliances such as iPaq PDA, Samsung S3C2400 board, Zaurus PDA, and on Home Server that uses x86 processor. Qplus-P graphic library is provided as a of Qplus-P target builder.

• Journal of the Korean Society of Radiology
• /
• v.1 no.1
• /
• pp.39-44
• /
• 2007

In this study, wireless measurement technique for human motion was developed to monitor movement disorder patients during their daily life. MICA, TinyOS, and nesC, developed by UC Berkeley, were used as wireless sensor, its software platform, and programming language. The human motion data, generated by two axial accelerometer(ADXL202) was transmitted to PDA(iPaq3630) by 916Mhz short range communication chip(TR1000). It could be stored at PDA by simple Windows CE programming. To test the developed device, it was attached at human chest and the acquired data was shown as a graph during his motion of sitting, standing, and lying. The result showed that human motion could be logged without any hooking and constraints. Therefore, this device can be used to monitor patient's movement disorder and activity of daily life(ADL).

• Archives of design research
• /
• v.16 no.2
• /
• pp.301-310
• /
• 2003

The interface design of mobile products has become a hot issue recently as a variety of products are being developed for extended usages. There have been two different views on interface design of mobile products like PDAs(personal digital assistants) or cellular phone. One 치aims that the current interface design of PC cannot be directly applied because mobile products have their own specific functions and requirements. On the meantime, the other argues that an extended application of PC metaphors to mobile products can have advantages because users'PC experiences can reduce the learning efforts and thus contribute to intuitive understanding mobile products. In this research, two types of PDAs, developed according to the aforementioned conflicting philosophies were compared and evaluated, based on laboratory-based usability testing conducted by novice users. The experiment consists of asking subjects to perform identical tasks for the two different types of products. The interaction data collected during usability testing were analyzed in terms of time taken, rate of success of tasks and errors. The experiment shows that there were some meaningful effects of users'experience of PC on the usability of PDAs.