• IEMEK Journal of Embedded Systems and Applications
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• v.14 no.2
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• pp.97-102
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• 2019

Multi-queue I/O block layer has been recently employed in Linux kernel to support fast storage devices such as NVMe SSDs, but it lacks differentiated I/O services yet. In this paper, we propose an I/O scheduling scheme that can improve the user responsiveness of foreground processes, which are closely related to user satisfaction. To this end, we redesign the existing multi-queue block layer to classify the I/O requests from foreground processes and schedule them by exploiting the feature of NVMe interface. Experimental results show that latency and launch time of the foreground processes have been significantly improved compared to original Linux kernel.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.11a
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• pp.900-904
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• 2001

PDA(Personal Digital Assistant)는 GUI(Graphical User Interface) 환경이 필수적이다. 최근 기존의 개인정보 관리기능 외에 휴대단말기를 내장한 인터넷 기능, 멀티미디어 기능, 게임 등이 가능한 고성능의 PDA가 일반화됨에 따라, 기존의 단일 task 환경 대신 뛰어난 GUI와 멀티미디어 환경을 지원하는 내장형 운영 체제가 사용될 전망이다. 본 논문에서는 Linux의 GTK+/GDK(GNU Image Manipulation Program Toolkit) 툴킷을 이용하여 Framebuffer를 직접적으로 사용할 수 있게 하고, 불필요한 내부 함수를 제거함으로써 X-윈도우시스템으로 인한 오버헤드 및 저장공진을 줄일 수 있는 내장형 운영체제를 설계 및 구현한다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.259-264
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• 2003

In this paper, web based monitoring systems are implemented using embedded Linux. The external equipment is controlled via HTTP protocol and web browser program. HTTP protocol is ported into Linux. A micro web server program and external equipment control program are installed on-board memory using CGI to be accessed by web browser. Experimental result of the proposed web based monitoring systems can be used in automation systems and remote distributed control via internet using web browser.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10c
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• pp.391-393
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• 2002

KGDB는 리눅스 커널을 위한 소스 레벨 디버거로서, GDB와 함께 동작하여 커널 개발자가 리눅스 커널을 응용 프로그램처럼 디버깅 할 수 있는 기능을 제공한다. 현재 KGDB는 X86 계열의 하드웨어를 위한 리눅스에 오픈 프로젝트로서 커널 버전 2.4.18 까지 개발되어있다. 본 논문에서는 X86 용 리눅스만을 위한 KGDB를 확장하여, 내장형 시스템에 널리 사용되는 ARM 프로세서 기반의 하드웨어에서 Linux 커널을 개발할 때에도 KGDB를 이용할 수 있도록 프로세서 의존적인 부분을 구현하고, 이를 커널에 통합하여 삼성에서 개발된 ARM920T 기반의 S3C2400 보드에서 동작실험을 하였다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.2
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• pp.316-321
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• 2017

With the recent wide adoption of Linux in the fields of IoT, embedded, mobile, desktop and server industries, the importances of understanding the Linux system architecture as well as customizing the Linux system are increasing very steeply. Accordingly, the capabilities of building every component of Linux system from source code files have been important. The LFS (Linux From Scratch) site[1] guides the steps of building the basic Linux system from source files. The steps consist of build host preparation step, temporary system building step, final system building step, and system configuration and boot preparation step. However, the underlying concepts behind the steps used in building LFS are difficult to understand, particularly to the beginner. This paper analyzes the LFS build steps and reveal the core build concepts and principles used in each step. Additionally, this paper shows the measured package build times obtained from our build experience.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.118-118
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• 2003

• Proceedings of the Korean Information Science Society Conference
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• 2004.10a
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• pp.670-672
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• 2004

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.1
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• pp.25-29
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• 2013

Recently ARM processor's processing power has been increasing rapidly as it has been applied to consumer electronics products. Because of its computing power and low power consumption, it is used to various embedded systems.( including vision processing systems.) Embedded linux that provides well-made platform and GUI is also a powerful tool for ARM based embedded systems. So short period to develop is one of major advantages to the ARM based embedded system. However, for real-time date processing applications such as an image processing system, ARM needs additional equipments such as FPGA that is suitable to parallel processing applications. In this paper, we developed an embedded system using ARM processor and FPGA. FPGA takes time consuming image preprocessing and numerical algorithms needs floating point arithmetic and user interface are implemented using the ARM processor. Overall processing speed of the system is 60 frames/sec of VGA images.

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.151-155
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• 2005

Telemedicine uses common technologies that provide a conduit for information exchange between physicians nurses and patients. In addition to patient records, medical professionals can obtain vital signs and other reference data through telemedicine applications. also, recent advancement in RF technology and wireless communications has enabled the development of Ubiquitous networks. Mobile telemedicine involves more than just communicating via mobile phone of PDA that sends and receives medical data on Portable Internet. this paper describes the design of a mobile telemedicine PDA prototype based on Embedded Linux that can be used to monitor the medical information using a single board computer(SBC). This system would be very useful for patients with chronic illness, especially in an emergent environment, and for containing medical cost in the aged society.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.920-923
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• 2002

As the new technologies, such as IEEE 1394, USB, Bluetooth, PLC are appeared, the embedded real time operating system which is satisfied the various technologies is needed. This paper proposed and implemented C standard library which is independently used in real time operating system and which supports an application development interface. The proposed C standard library is based on EL/IX, an Embedded Linux API based on POSIX, which is suitable for other embedded operating systems as well. And because the proposed C standard library has four level, it supports various Internet appliances, such as digital TV, settop box. The developed C library is tested at Qplus-P real time operating system which is developed at ETRI.