• Proceedings of the Korea Information Processing Society Conference
• /
• 2010.11a
• /
• pp.1753-1756
• /
• 2010

최근 들어 가상화 기술은 서버의 통합에 뿐만 아니라, 임베디드 시스템에서도 널리 사용되고 있다. 하지만, 가상화 시스템에서는 물리 프로세서가 게스트 운영체제에게 직접 전달되지 않으며, 게스트 운영체제는 가상 프로세서를 통해서 실행할 수 밖에 없다. 따라서, 기존의 처리량 기준의 공평성 스케줄러가 가상머신 모니터에서 동작하는 경우, 실시간 스케줄링이 불가능하다. 본 연구에서는 멀티코어 기반의 가상화 시스템에서 실시간 태스크의 실행을 보장하는 기법을 소개한다. 특히, 본 논문에서는 계층형 스케줄링의 특성과 최대 병렬성 조건을 통하여 멀티코어 가상머신의 스케줄 가능성 분석 기법을 제시한다.

• Journal of KIISE:Computer Systems and Theory
• /
• v.37 no.1
• /
• pp.35-42
• /
• 2010

Guest operating systems running over the virtual machines share a variety of resources. Since CPU is allocated in a time division manner it consequently leads them to having the unknown physical time. It is not regarded as a serious problem in the server virtualization fields. However, it becomes critical in embedded systems because it prevents guest OS from executing real time tasks when it does not occupy CPU. In this paper we propose a hypercall to register a timer service to notify the timer request related real time. It enables hypervisor to schedule a virtual machine which has real time tasks to execute, and allows guest OS to take CPU on time to support real time. The following experiment shows its implementation on Xen-Arm and para-virtualized Linux. We also analyze the real time performance with response time of test application and frames per second of Mplayer.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.10
• /
• pp.191-200
• /
• 2010

The "intelligent internet power outlets" realized in this study use Internet environment to connect electrical and electronic products to the Net as well as to enable remote monitoring and control. They also have temperature and light sensors, and even offer scheduling options by means of a universal calendar run by an inner real-time timer. Furthermore, they control 4 outlets handling 4 external input conditions and infrared remote control with easy-to-use functions for home automation control. The user interface is equipped with an embedded Web server and UDP protocol handler, and which also allows special control programs be used with the Web browser. Thus, installing this real-time power control function with optimal scheduling and various communication functions will provide you with energy-efficient power outlets outfitted with the increasingly popular "standby power" electric power efficiency.

• Journal of Korea Multimedia Society
• /
• v.15 no.7
• /
• pp.920-930
• /
• 2012

In this paper, we designed and built a wired temperature controller system which is based on ASIC for a wireless temperature controller system based on FPGA. FPGA devices and wireless controller systems are growing quickly especially for industrial systems for sensing temperature and humidity. FPGA can set up a desired system and a CPU, and directly set up or change a peripheral device based on an IP quickly for an affordable price. This wireless system is easy to install in the field where there are lots of changes and the system is complex. It also has advantages for maintenance. In this study, we are using a 32 bit RISC CPU based on MicroBlaze, with a touch interface, peripheral device, and porting the embedded Linux. Also, we added wireless communication using ZigBee. With this system we provide remote monitoring and control through the web by adding a web server. Compared to the original system, we say not only a performance improvement, but also more efficient development and cheaper costs. In this study, we focused especially on building a better development environment and a more effective user interface.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.10a
• /
• pp.427-430
• /
• 2012

최근 차량용 블랙박스, 자동 운전 시스템, 어라운드 뷰 시스템 등과 같은 운전자의 편의와 안전을 위한 장치 및 시스템들이 개발되고 있다. 현재 운전자를 위한 보조 시스템으로 구글(google)의 자동 운전 시스템(Auto Car Driving System)과 현대 모비스(hyundai mobis)의 AVM 시스템(Around View Monitoring System) 등의 다양한 차량용 편의장치 시스템들이 등장했다. 위와 같은 다양한 ECU들을 관리하기 위한 서버 및 저장 장치 역할을 할 수 있는 고사양의 Car PC의 장착이 필수적이다. 기존의 AVM 시스템은 차량 주변을 실시간으로 제공하기 위해 임베디드 또는 별도의 차량용 네트워크를 통해 임베디드 시스템 또는 SoC(System On Chip)형태의 하드웨어 기반으로 개발되고 있다. 하지만 고사양의 Car PC 기반에서는 별도의 비용없이 소프트웨어로 구현이 가능하다. 본 논문에서는 차량의 전 후 좌 우에 장착된 4대의 카메라로부터 입력된 차량 주변 상황을 한눈에 보여주는 AVM 시스템(Around-View Monitoring System)을 위한 카메라 보정 및 정합 처리 모듈 및 AVM 시스템을 Windows를 O/S로 하는 PC 내부에서 기존의 AVM 시스템을 이용하여 화면에 전 후 좌 우 버튼을 각각 만들어 버튼을 터치했을 때, 각 버튼에 해당되는 영상이 AVM 시스템과 함께 출력되도록 하거나 디스플레이에 Full 버전으로 출력되도록 S-UI(Smart User Interface)를 설계 및 구현한다. 제안하는 AVM 시스템과 기존의 AVM 시스템의 성능과 기능을 비교 분석함으로써 제안하는 영상 처리 모듈을 이용하여 추가 비용이 발생하지 않는 AVM 시스템의 구현 가능성을 검증한다.

• The Journal of the Korea Contents Association
• /
• v.9 no.11
• /
• pp.90-99
• /
• 2009

This paper presents the implementation of RFID EPC global network educational system based on using 900MHz air interface between the reader and the active tag. The software of reader and the active tag is developed on embedded environment, and the software of PC controlling the reader is based on window OS operated as the server. The ATmega128 VLSI chip is used for the processor of the reader and the active tag. As the development environment, AVR compiler is used for the reader and the active tag of which the programming language is C. The visual C++language of the visual studio on the PC activated as the server is used for development language. Main functions of this system are to control tag containing EPC global Data by PC through the reader, to obtain information of tag through the internet and to read/write data on tag memory. Finally the data written from the active tag's memory is sent to the PC via the reader as "read" operation and compare the received data with one already sent to the tag. Software implementation of 900MHz EPC global RFID educational system is done on the basis of these functions.

• Proceedings of the Korea Contents Association Conference
• /
• 2009.05a
• /
• pp.687-692
• /
• 2009

This paper presents the development of RFID educational system based on 900MHz air interface between the reader and the active tag. The software of reader and the active tag is developed on embedded environment, and the software of PC controlling the reader is based on window OS operated as the server. The ATmega128 VLSI chip is used for the processor of the reader and the active tag. As the development environment, AVR compiler is used for the reader and the active tag of which the programming language is C. The visual C++language of the visual studio on the PC activated as the server is used for development language. Main functions of this system are to control tag containing EPC global Data by PC through the reader, to obtain information of tag through the internet and to read/write data on tag memory. Software design of 900MHz RFID/USN educational system is done on the basis of these functions.

• The Journal of the Korea Contents Association
• /
• v.7 no.12
• /
• pp.245-253
• /
• 2007

In this paper, we propose an effective web service software platform for remote monitoring and control. We removed the servlet container for better web service performance so as to improve the gSOAP processing which is an essential element of web service implementation. Furthermore, we designed the web service server/client software platform which can be applied to robot or ubiquitous sensor applications. For validation of this study we tested it by manufacturing robot hardware for monitoring control which combined tanks and sensors on a LDS4000 engine board mounted with a PXA270 processor. The practical excellence and the efficiency of the result of this study was validated by the comparison of gSOAP message exchange load between the web service client application and the conventional remote monitoring control technique through a web server.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.10B
• /
• pp.883-890
• /
• 2006

The study of sensor network database is beginning to liven up as we are interested in Ubiquitous Computing technology in hardware, communication, database and so on. Especially, as new smart sensors have capabilities of real-time information gathering and analysis of each sensor node, data processing becomes an important issue in Ubiquitous Computing. In thesis, we have applied TinyDB(query processing system) to carry sensor node with line tracer which can follow the fixed path. After we gathered data around path, we have processed data in TinyDB GUI, gathered data, displayed data on a web server. Also we have a web browser on an embedded board for convenient user interface and implemented touch screen such that users can operate with a finger.

• Journal of Internet Computing and Services
• /
• v.8 no.4
• /
• pp.51-59
• /
• 2007

This paper presents the development of RFID educational system based on using 900MHz air interface between the reader and the active tag. The software of reader and the active tag is developed on embedded environment, and the software of PC controlling the reader is based on window OS operated as the server. The AT89C51ED2 VLSI chip is used for the processor of the reader and the active tag. As the development environment, Keil compiler is used for the reader and the active tag of which the programing language is C. The visual C language of the visual studio on the PC activated as the server is used for development language. To verify the function of the system, PC gets the tag's identification number through the reader and send the data to with the active tag memory a certain contents as "wite" operation. Finally the data written from the active tag's memory is sent to the PC via the reader as "read" operation and compare the received data with one already sent to the tag.