• Proceedings of the Korean Information Science Society Conference
• /
• 2001.04a
• /
• pp.100-102
• /
• 2001

Intensive I/O bandwidth demand of the multimedia streaming service puts significant burden on file system. Different from the legacy text based or image data, the semantics of the data in multimedia format can be significantly affected if the data block is not delivered by the predefined deadline. The legacy file system used in Unix or Unix like environment is designed to efficiently handle the files who sizes range from few hundreds of byte to several tens of gigabytes. This fundamental design philosophy results in the file system based on multi level skewed tree structure. Multi level i-node structure has significant drawback when the application performs sequential read operation. In this article, we present the result of the performance study of the file system which is specifically designed for handling multimedia streams. We implemented the file system on Linux Operating System environment and examines the performance behavior of the file system under streaming I/O workload. The result of the study shows that the proposed file system performs much more efficiently than the ext2 file system of Linux does.

• 한국방재학회:학술대회논문집
• /
• 2007.02a
• /
• pp.414-417
• /
• 2007

A methodology for XML documentation of the structural calculation document is presented to support manipulation of the design information on the internet. The text file format is chosen as a neutral format because it can be easily translated from office documents generated from engineering practice. The first word of each line is compared with the reserved numbering groups, and relative levels among the lines are defined to generate the hierarchically structured XML document of the text file. The demonstration subjected to sample general documents and structural calculation documents shows that the prototype application module based on the developed methodology can be adopted to build the database of design information which supports the safety management of infrastructures.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2009.01a
• /
• pp.89-92
• /
• 2009

최근 일반인들에게 널리 보급되고 있는 DSLR 디지털 카메라로 촬영되는 정지 이미지는 범용의 JPEG 포맷이나 제조사별 독자적인 RAW 파일 포맷으로 저장매체에 저장된다. 이와 함께 PMP 등의 휴대용 멀티미디어 기기를 활용하여 촬영된 RAW 파일 포맷을 재생 및 확인하기 위한 요구가 증대되고 있지만, RAW 파일 포맷이 디지털 카메라 제조사별로 다르고, 해당 포맷에 대한 구체적인 정보가 공개되지 않는 이유로 대부분의 휴대용 멀티미디어 기기에서 RAW 파일 재생 기능을 지원하지 못하고 있는 실정이다. 본 연구에서는 RAW 파일 포맷을 분석하여 향후 임베디드 멀티미디어 기기에서 모든 RAW 파일 포맷을 지원할 수 있는 라이브러리 구축을 위한 사전 작업을 수행하였다. Cannon의 CRW, CR2 포맷과 Nikon의 NEF 포맷을 분석한 결과를 설명한다. 분석 결과를 바탕으로 RAW 파일 포맷에서 JPEG 파일음 성공적으로 추출하였다. MRW, PEF, DCR, DNG 등의 RAW 파일 포맷을 추가로 분석하여 모든 RAW 파일을 재생한 수 있는 임베디드 장비 및 PC용 RAW 파일 재생 라이브러리를 구축할 것이다.

• IE interfaces
• /
• v.17 no.2
• /
• pp.190-199
• /
• 2004

Recently, many enterprises are introducing a workflow management system for the successful implementation of BPR(Business Process Reengineering). Proposed in this study is the workflow management system which has a light-weight component structure and an XPDL(XML Process Definition Language) file interpretation facility. The XPDL is the standard process definition exchange format developed by WfMC(Workflow Management Coalition). The major causes of inefficiency at current implementations of workflow management systems are the centralized workflow engine structure and the use of proprietary workflow definition format among most solutions. The proposed light-weight component structure in this study is the intermediate structure that takes the strength of both centralized and distributed workflow engines. And a prototype workflow system which uses an XPDL process definition file as input is developed through the thorough analysis of functional requirements.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.22 no.2
• /
• pp.163-178
• /
• 2004

In this study, the CIE RGB color space which was one of the most popular device-dependent application program in digital image processing was adopted to make the profile with the device information. The profile was applied to the digital image of a JPEG file format. The result was compared with the color reproduction of another digital image of a JPEG file format, which was made in the e-sRGB color space that had the color spaces allocated to each reproduced color of an image and device-independent colors. In this way it was investigated which color space was more appropriate for digital image processing for web printing and if the e-sRGB color space was good as a color management tool that didn't depend on a device in processing a digital image for web printing.

• Proceedings of the KSME Conference
• /
• 2000.11b
• /
• pp.674-679
• /
• 2000

An air handling unit(AHU) has been usually designed by manual calculations. Drawing works together with design calculations should be redone far every designing work, and also be needed to make some corrections of them. In order to design the AHU more efficiently, an AHU program has been developed. The developed program on the Windows environment is operated by the graphic user interface(GUI) realized using the Visual Basic Interpreter. The program provides calculation sheet of coils, weights and pressures in a MS-Excel file format as well as design drawing of the AHU in a Auto CAD file format idealized by AutoLISP. Those files of the commercial softwares make easier for a designer to transfer design results to the another company for bid via e-mail.

• Electronics and Telecommunications Trends
• /
• v.23 no.3
• /
• pp.106-118
• /
• 2008

본 고에서는 최근 표준화가 완료된 MPEG-A(ISO/IEC 23000) Part 9 DMB-AF의 표준화 배경 및 서비스 모델을 소개하고 기술적인 구성요소에 대해 설명한다. DMB-AF는 MPEG-4 Part 12 ISO Base Media File Format에 기반한 DMB 콘텐트 전용 파일 포맷으로, 다양한 종류의 지상파 DMB 및 위성 DMB 콘텐트를 체계적으로 표현하고 효과적으로 저장 및 접근하며 안전하게 보호/유통하기 위한 기술들이 포함되어 있다. 이러한 DMB-AF 표준은 다양한 DMB 콘텐트들을 적절히 연계하여 방통융합 환경에서 다양한 비즈니스 기회를 창출할 수 있는 공통의 프레임워크를 제공할 뿐 아니라, 저장매체를 매개로 하여 사용자가 원하는 시점에 원하는 프로그램을 원하는 장치에서 시청할 수 있도록 하는 DMB-Anytime 서비스를 가능하게 한다.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 1999.05a
• /
• pp.81-86
• /
• 1999

The STL file format is an approximation of 3-D model with triangular facets. STL is a standard input file format of Rapid Prototyping(RP) equipment. In computer graphics, a circle has been approximated with an inscribed polygon, which causes an error between the real and approximated circles. In this study, an intersecting polygon has been used to approximate the circle and applied to produce more accurate RP part. The newly proposed method shows it's excellence in part accuracy.

• Korean Journal of Computational Design and Engineering
• /
• v.7 no.2
• /
• pp.89-95
• /
• 2002

VRML data, which is mainly structural element, is frequently used for modeling and visualizing 3D objects. Although there can be variations, it is a usual practice to represent 3D shapes in VRML format. Ever since the advent of Internet, there have been strong needs to transfer shape data through Internet. Because of this need, it is necessary to transform a data file in VRML or similar format into a more convenient form to transfer through the network. In a VRML file, a model is sometimes divided into a set of triangle meshes due to several practical reasons. However, this causes various demerits for the fast transmission. Therefore, it is more efficient to merge the mesh sets into one mesh set for the transmission. In this paper, we present the problems in the merge process and the techniques to handle the situation.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2004.11a
• /
• pp.623-626
• /
• 2004

EVM(Embedded Virtual Machine)은 임베디드 시스템을 위한 가상기계로서 플랫폼에 독립적이며, 모바일 디바이스와 디지털 TV등에 탑재할 수 있는 핵심 기술로 다운로드 솔루션에서는 꼭 필요한 기술이다. SIL(Standard Intermediate Language)은 임베디드 시스템을 위한 가상기계의 표준 중간 언어로 객체지향 프로그래밍 언어와 순차 적인 프로그래밍언어를 모두 수용할 수 있다. SIL로 기술된 프로그램이 EVM 에서 실행되기 위해서는 EFF(Executable File Format)형태로 변환되어야 한다. 임베디드 시스템을 위한 실행 파일 포맷인 EFF 는 구조가 간결하며 확장이 용이한 특징을 지닌다. 또한 메타데이터와 표준 중간 언어가 서로 독립적으로 구성되어 분석이 쉽고 타입 체크가 편리한 구조이다. 본 논문에서는 가상기계를 위한 표준 중간 언어인 SIL 을 EVM 에서 실행 가능한 형태로 변환시켜주는 실행 파일 포맷 생성기(EFF Generator)를 설계하고 구현한다. 먼저, SIL 구조를 위한 SIL 문법을 설계하고 파서 생성기(PGS)를 사용하여 SIL 프로그램을 위한 어휘분석기와 구문분석기를 구현한다. 그리고 AST를 생성한 후. 포맷 생성기를 통하여 AST를 운행하며 EFF를 생성한다.