• 대한임베디드공학회논문지
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• 제1권2호
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• pp.90-103
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• 2006

There are many file systems in various operating systems. Those are usually designed for server environments, where the common cases are usually 'multiple active users', 'great many small files' And they assume a big main memory to be used as buffer cache. So the existing file systems are not suitable for resource hungry embedded systems that process multimedia data streams. In this study, we designed and implemented a new file system which efficiently stores and retrieves multimedia data steams. The proposed file system has a very simple disk layout, which guarantees a quick disk initialization and file system recovery. And we introduced a new indexing-scheme, called the time-based indexing scheme, with the file system. With the indexing scheme, the file system maintains the relation between time and the location for all the multimedia streams. The scheme is useful in searching and playing the compressed multimedia streams by locating exact frame position with given time, resulting in reduction of CPU processing and power consumption. The proposed file system and its APIs utilizing the time-based indexing schemes were implemented firstly on a Linux environment, though it is operating system independent. In the performance evaluation on a real DVR system, which measured the execution time of multi-threaded reading and writing, we found the proposed file system is maximum 38.7% faster than EXT2 file system.

• 산업경영시스템학회지
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• 제20권41호
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• pp.189-196
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• 1997

Multimedia systems present information by various media, for example, video, sound, music, animation, movie, etc., in addition to the text which has long been used for conveying the information. But using several media may cause users' confusion and poorly designed user interface often aggravate the situation. Hypermedia systems allow the retrieval and representation of multimedia information using navigation and browsing mechanisms. Typically, there are two major navigation problems in a hypermedia compared to the ordinary user interface: disorientation and cognitive overload. In this study, the multimedia system was studied from the viewpoint of usability. Practical usability evaluation needs cost-effective, low-skill, and low- investment methods. The 'discount usability engineering' method, one of these methods, is based on the use of the following techniques: scenarios, simplified thinking aloud, and heuristic evaluation. The discount usability engineering method was applied to the usability evaluation of multimedia CD-ROM title.

• 한국통신학회논문지
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• 제27권6B호
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• pp.593-600
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• 2002

The reverse link signal power required for multimedia traffic in multipath faded single-code (SC-) and multi-code CDMA (MC-CDMA) systems is investigated. The effect of orthogonality loss among multiple spreading code channels is herein characterized by the orthogonality factor. The required signal power in both the CDMA systems is then analyzed in terms of the relative required signal power ratio of data to voice traffic. The effect of varying system parameters including spreading bandwidth, the of orthogonality factor, and the number of spreading codes are examined. Analytical results show that MC-CDMA users transmitting only a single traffic type require significantly more power than SC-CDMA users with only a single traffic type. On the other hand, MC-CDMA users transmitting multimedia traffic require power levels approximately identical to SC-CDMA users with multimedia traffic. The results can be used in the design of radio resource management (e.g., power allocation) scheme for wireless multimedia services.

• 한국정보시스템학회:학술대회논문집
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• 한국정보시스템학회 1996년도 추계학술발표회 발표논문집
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• pp.110-123
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• 1996

Misunderstanding of multimedia in the computer industry, the confusion of consumers, and the lack of understanding of technology in the human context provide an impetus for examining and speculating on the future of multimedia. "What can a multimedia technology do ?" is not a sufficient question for consumers until we add "for whom." Both how the relevant technology is likely to develop and how human choices would be made are examined with a focus on historical trend in media technology adoption.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 1996년도 추계 학술 발표회 발표논문집
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• pp.110-123
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• 1996

Misunderstanding of multimedia in the computer industry , the confusion of consumers, and the lack of understanding of technology in the human context provide an impetus for examining and speculating on the future of multimedia. "What can a multimedia technology do?" is not a sufficient question for consumers until we add " for whom" . Both how the relevant technology is likely to develop and how human choices would be made are examined with a focus on historical trend in media technology adoption.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2002년도 춘계학술대회 논문집
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• pp.3-8
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• 2002

This paper introduces the basic concept of computational modeling of perception processes for multimedia data. Such processes are modeled as hierarchical inter- and intra- relationships amongst information in physical, physiological, psychological and cognitive layers in perception. Based on our framework, this paper gives the algorithms for content-based retrieval for multimedia database systems.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.995-998
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• 2005

A task in imprecise computation consists of mandatory part and optional part. The optional part can be executed partially and the quality of service is measured by the amount of the execution. Many paper showed that multimedia systems are good applications of imprecise computation. It is important to guarantee QoS which is a critical factor in multimedia systems. Previous works didn't consider QoS and processor slack were assigned randomly to tasks. This paper presented a systemic slack assignment method according to QoS levels of tasks. A simulation result showed that our method can be a good choice for multimedia systems with QoS requirement.

• 한국항행학회논문지
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• 제12권6호
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• pp.673-680
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• 2008

멀티미디어 시스템의 보안은 멀티미디어 자산 자체를 보호하는 것과 시스템을 보호하는 것, 두 가지 측면으로 나누어 생각할 수 있는데, 이들 두 가지 측면을 별도로 고려한다고 하여도 보안관리의 중요성은 결코 떨어지지 않는다. 본 논문에서는 멀티미디어 시스템의 정보보호수준을 관리하기 위한 관리적 측면에서의 프랙티스들을 도출하고, 이를 적용하기 위해 그룹화하였다.

• 정보처리학회논문지C
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• 제9C권5호
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• pp.757-764
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• 2002

본 논문에서는 분산 멀티미디어 응용을 위한 객체 지향형 프레임워크 방식으로 설계된 네트워크 멀티미디어 관리 시스템 개발에 관한 설계 이슈 및 프로토타입 개발 경험을 기술하고, 특히 멀티미디어 관리 시스템의 일부로서 개발한 비디오 서버 상에 적용 가능한 통합형 QoS-자원 협상 프로토콜의 주요 특징에 관하여 설명한다. 구현된 멀티미디어 프레임 워크 상에서 효율적인 멀티미디어 스트리밍을 지원하기 위하여 새로 제안된 QoS 협상 정책을 실제 서버에 적용하는데 있어서 고려해야 할 중요 이슈에 대해서도 분석하였다.

• 경영정보학연구
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• 제1권2호
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• pp.73-87
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• 1999