• Journal of Korea Multimedia Society
• /
• v.7 no.10
• /
• pp.1443-1451
• /
• 2004

In this paper we propose a new packet scheduling mechanism to improve TCP throughput and fairness with estimated link state information in wireless networks, in which mobile hosts are receivers. Since a priori estimated link state information is used in this proposed mechanism, the entire packet transmission time can be reduced. In other words, packets scheduling procedure is performed before packets are transmitted using estimated link state. The proposed mechanism also has an temporary FIFO queue to store packets which are on the head of queue and can not be transmitted due to bad link state. Using this temporary FIFO queue, HOL(Head of Line) problem of FIFO queue can be resolved.

• Journal of Korea Multimedia Society
• /
• v.11 no.10
• /
• pp.1460-1470
• /
• 2008

As the performance of recent mobile systems increases, a vector graphic has been implemented to represent various types of dynamic menus, mails, and two-dimensional maps. This paper proposes a hardware accelerator for open vector graphics (OpenVG), which is widely used for two-dimensional vector graphics. We analyze the specifications of an OpenVG and divide the OpenVG into several functions suitable for hardware implementation. The proposed hardware accelerator is implemented on a field programmable gate array (FPGA) board using hardware description language (HDL) and is about four times faster than an Alex processor.

• Journal of Korea Multimedia Society
• /
• v.8 no.2
• /
• pp.137-153
• /
• 2005

This paper presents a transcoding method that dynamically adapts Web pages to various devices. The proposed method is based on a CC/PP profile that is a standard description of a device's context information. Additionally, to support a sophisticated transcoding, we define an annotation schema for representing additional information about original contents. Since a mobile device has a screen of limited size, A Web page is splitted into many small ones. Our method constructs a navigation-map that represents the hierarchical relations among the splitted pages. Experimental results with various Web contents show that the proposed method is superior in terms of user's convenience of navigation and the transcoding Quality.

• Journal of Korea Multimedia Society
• /
• v.8 no.8
• /
• pp.1142-1151
• /
• 2005

Various kinds of studies for building up U-Korea are now underway. Especially, RFID comes into the spotlight as a core technology of Ubiquitous. Though, the development of higher levels of application is far behind the hardware-based technology in RFID application system. For that reason, In this paper suggests technology using RFID on Ubiquitous and embodies the effective health care application which is one of the application services of user-centered environment It realizes the system which enables us to manage and send data about changing prescriptions and locations of patients effectively under the basis of RFID tag and mobile devices. It also provides the high quality of practical effectiveness of entire system throughout the realization of applications of application server and mobile device. on the basis of framework for providing the various kinds of services and physical elements.

• Journal of Korea Multimedia Society
• /
• v.16 no.4
• /
• pp.510-519
• /
• 2013

In this paper, we propose a voice-annotation browsing system that make the reading-disabled people to be able to find and play the existing voice-annotations. The proposed system consists of 4 steps: input, ranking & recommendation, search, and output. For the reading-disabled people depending only on the auditory sense, all steps can accept voice commands. To evaluate the effectiveness of our system, we design and implement an android-based mobile e-book application supporting the voice-annotation browsing ability. The implemented system is tested by a number of blind-folded users. As a result, we can see almost all the reading-disabled people can successfully and easily reach the existing voice-annotations they want to find.

• Journal of Korea Multimedia Society
• /
• v.10 no.2
• /
• pp.170-178
• /
• 2007

In restricted resources based on mobile environment, we can use an embedded database technology for management of MPEG-7 data. At this time, some XML clustering methods can be used. But, to improve the performance efficiency better, a new clustering method is need to store effective MPEG-7 document. In this paper, we have designed and implemented a MPEG-7 document management system to store MPEG-7 document effectively in mobile device such as PDA. The system used the 버클리 DB XML as a native embedded XML database system based on the clustering method of MPEG-7 data.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2002.05c
• /
• pp.105-111
• /
• 2002

최근까지 웹은 컴퓨터 상에서의 디스플레이, 키보드, 포인팅 장치들과 같은 비주얼 인터페이스를 통해서 정보 전달 및 서비스를 해오고 있다. 또한 이들은 일부의 모바일용 서비스를 제외하고 대부분이 익스플로어나 네스케이프 등의 웹브라우져를 지원하는 서비스를 해오고 있다. 이와 같은 시스템은 시간과 공간에 제약이 있으며 지원하는 브라우저가 있어야 하는 단점이 있다. 전화의 보급률은 컴퓨터나 기타 장치들에 비해 높고, 음성은 사람에게 쉽게 다가갈 수 있고 편하게 사용할 수 있는 인터페이스이다. 본 논문에서는 지금까지의 보는 것 중심의 웹 서비스를 듣고 말하는 웹 서비스로 음성 인식 항공 정보 시스템으로 설계ㆍ구현하였다.

• Journal of Digital Contents Society
• /
• v.13 no.3
• /
• pp.401-412
• /
• 2012

Communication through smartphones is creating a new paradigm of mobile communication beyond the restrictions of mobility and space. The mobile instant messengers of the smartphone, which began on the desktop environment, are providing various communication features, including multimedia contents, texts, and voice. Kindergartens and nurseries are using Websites, phones, SMS, printed materials, handwritten notifications, etc. to communicate with the parents. IsPlus was developed to facilitate the communication between the parents and the teachers, including exchanges of pictures and videos, chatting, and attendance management using smartphones. This is meaningful in that it is an early smartphone mobile messenger for educational institutions for infants and preschoolers. This study presented a new approach to the development of a mobile messenger for a specific group of users by analyzing the user environment, communication types, application planning process and interface design development using storytelling.

• Proceedings of the Korean Information Science Society Conference
• /
• 2006.10a
• /
• pp.372-376
• /
• 2006

본 논문에서는 홈 내에서 헬스케어 상황정보 서비스를 제공하기 위한 모바일 프락시에 대해 기술한다. 모바일 프락시는 헬스케어 홈 서비스의 목적에 따라 분산자원의 통합 및 맞춤형 관리모델인 분산객체그룹 프레임워크를 기반으로 한다. 모바일 프락시의 주요 기능은 이동성을 지원 및 멀티미디어 스트림 동기화 그리고 그룹통신 지원한다. 특히, 클라이언트의 가용환경에 따라 수행객체에 대한 이동성을 제공한다. 이를 기반으로 헬스케어 상황정보 서비스를 제공하기 위해 사용되는 상황정보는 거주자의 위치, 홈 내에 설치된 센서/기기로부터 수집된 위치, 건강 그리고 쾌적환경 정보를 포함한다. 또한 헬스케어 상황정보 서비스를 위한 응용객체, 자원들의 그룹관리 지원 DOGF를 기반으로 이동성 지원 컴포넌트인 모바일프락시는 거주자 위치이동에 따라 적합한 헬스케어 상황정보 서비스를 제공한다. 모바일프락시를 이용한 헬스케어 상황정보 서비스는 헬스케어 지원 음악치료, 원격상담 서비스와 처방 주의 및 스케줄 알림서비스를 구현했다. 끝으로 제안한 환경에서 거주자의 위치, 시간 및 상황인식에 따라 구현하여 수행한 헬스케어 상황정보 서비스 결과를 보였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.10a
• /
• pp.927-928
• /
• 2016

In the past, the way of sharing data in various devices was to use a physical method such as USBs. The radical development of communications technology and the users, who possess various multimedia devices, caused the need for the new way that people could share their data in various devices, and providing various digital resources by using the cloud computing service helps people solve the limit to sharing the resources in their PC. Therefore, this paper is to suggest the technology for synchronization of mobile devices, and the user-centered cloud service is applied to the technology. Having conducted the experiment, it has been discovered that applying the synchronization of mobile devices using the cloud service enabled to conduct the auto file synchronization and to minimize the bandwidth consumed during the synchronization process between two devices.