• Title/Summary/Keyword: real-time embedded system

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A Kernel-level RTP for Efficient Support of Multimedia Service on Embedded Systems (내장형 시스템의 원활한 멀티미디어 서비스 지원을 위한 커널 수준의 RTP)

  • Sun Dong Guk;Kim Tae Woong;Kim Sung Jo
    • Journal of KIISE:Computing Practices and Letters
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    • v.10 no.6
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    • pp.460-471
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    • 2004
  • Since the RTP is suitable for real-time data transmission in multimedia services like VoD, AoD, and VoIP, it has been adopted as a real-time transport protocol by RTSP, H.323, and SIP. Even though the RTP protocol stack for embedded systems has been in great need for efficient support of multimedia services, such a stack has not been developed yet. In this paper, we explain embeddedRTP which supports the RTP protocol stack at the kernel level so that it is suitable for embedded systems. Since embeddedRTP is designed to reside in the UBP module, existing applications which rely ell TCP/IP services can proceed the same as before, while applications which rely on the RTP protocol stack can request HTP services through embeddedRTp API. EmbeddedRTP stores transmitted RTP packets into per session packet buffer, using the packet's port number and multimedia session information. Communications between applications and embeddedRTP is performed through system calls and signal mechanisms. Additionally, embeddedRTP API makes it possible to develop applications more conveniently. Our performance test shows that packet-processing speed of embeddedRTP is about 7.5 times faster than that oi VCL RTP for multimedia streaming services on PDA in spite that its object code size is reduced about by 58% with respect to UCL RTP's.

Development of a Real Time System for The Vertical Mobile Robot (수직면 부착이동 로봇을 위한 실시간 시스템 구현)

  • Lee, Sang-Hoey;Yang, Suk-Won;Kim, Won-Bae;Park, Ju-Yi;Kim, Soo-Ho
    • Proceedings of the KIEE Conference
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    • 2006.07d
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    • pp.1991-1992
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    • 2006
  • this paper is described the Vortical Mobile Robot problem which can be generated a lot of error like gravity, mobile error between main control system of robot and application program and solution which is installed RTX( Real Time Extension ) Kernel to Embedded XP of main control board because it needs to guarantee real time between the main control board of robot and the motion drive board and to develop the remote operation system for real time robot control also in case The Vertical Mobile Robot that needs fast and stable motile control so it is proposed a guaranteed real time system

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Real-time Calculation of Geoid Applicable to Embedded Systems (내장형 시스템에 적용 가능한 지오이드의 실시간 결정)

  • Kim, Hyun-seok;Park, Chan-sik
    • Journal of Advanced Navigation Technology
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    • v.24 no.5
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    • pp.374-381
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    • 2020
  • In order to improve the vertical position accuracy, the advantages of GPS and barometric altimeter are combined and used, but in order to fuse the two sensors, the geoid altitude must be compensated. In this paper, we proposed a technique that can calculate geoid altitude in real time even in low-cost embedded systems applied to drones or autonomous vehicles. Since the reference EGM08 is determined by a polynomial of the 2160th order, real-time calculation is impossible in the embedded system. Therefore, by introducing a linear interpolation technique, the amount of calculation was increased, and the storage space was saved by 75% by using the integer geoid height as a grid point. The accuracy of the proposed technique was evaluated through simulation, and it was confirmed that the accuracy of the maximum error is -1.215 m even in the region where the geoid change is rapid.

Design and Implementation of An Object-Oriented Kernel Framework Reusable for the Development of Real-Time Embedded Multitasking Kernels (실시간 내장 멀티태스킹 커널의 개발에 재사용 가능한 객체지향 커널 프레임워크의 설계 및 구현)

  • Lee, Jun-Seob;Jeon, Tae-Woong;Lee, Sung-Young
    • Journal of KIISE:Computing Practices and Letters
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    • v.6 no.2
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    • pp.173-186
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    • 2000
  • Real-time embedded systems should accommodate many kinds of hardware platforms and resource management policies that vary depending on their operating environments and purposes. It is not an easy job to adapt a multitasking kernel to new system services and hardware platforms, as the kernel must strictly satisfy constraints on its size and performance. This paper describes the design and implementation of an object-oriented multitasking framework that can be reused for implementing microprocessor-based real-time embedded multitasking kernels, In this kernel framework, those parts that can vary depending on hardware platforms and system resource management policies are separated into the hot spots and encapsulated by abstract classes. Our framework thus can be effectively used to implement microprocessor-based real-time embedded kernels that demand high portability and adaptability.

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Implementation of Low-Power Ubiquitous Health System based on Real-Time Embedded Linux using ZigBee wireless communication (ZigBee를 이용한 실시간 임베디드 리눅스 기반의 저전력형 U-Health 시스템 구현)

  • Kwon, Jong-Won;Ayurzana, Odgerel;Park, Yong-Man;Koo, Sang-Jun;Kim, Hie-Sik
    • Proceedings of the KIEE Conference
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    • 2007.04a
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    • pp.436-438
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    • 2007
  • As the sensors and communication technology get advance, the remote health diagnosis for patients and senior persons at home are possible now without visiting doctors in hospitals. A low-power ubiquitous health check device was developed adapting Real-Time Embedded Linux is developed. This ubiquitous device is consisted of three sensors. The wrist type health checking terminal acquires periodically the health data by using a blood pressure sensor, a pulse sensor and a body temperature sensor. It transmits the health data to the access point located at the home center through the ZigBee wireless communication modem. This health data collector or access point device sends the data again to the main server operated in a hospital or health care organization. The health server control continuously the input data and sends an alarm signal to the assigned. doctor and responsible persons using cellular SMS when any dangerous events occur. This wrist type health check device has an embedded linux OS using Intel PAX255 MPU. The developed U-Health system is applicable for checking patients health in remote at home. And their family or related persons in remote site can check the patients health status at any time. They can be assured by receiving SMS record and alarm of emergency case which is transmitted from the health server.

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A Deadline_driven CPU Power Consumption Management Scheme of the TMO-eCos Real-Time Embedded OS (실시간 임베디드 운영체제 TMO-eCos의 데드라인 기반 CPU 소비 전력 관리)

  • Park, Jeong-Hwa;Kim, Jung-Guk
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.4
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    • pp.304-308
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    • 2009
  • This paper presents the deadline driven CPU-Power management scheme for the Real-Time Embedded OS: named TMO-eCos. It used the scheduling scenarios generated by a task serialization technique for hard real- time TMO system. The serializer does a off-line analysis at design time with period, deadline and WCET of periodic tasks. Finally, TMO-eCos kernel controls the CPU speed to save the power consumption under the condition that periodic tasks do not violate deadlines. As a result, the system shows a reasonable amount of power saving. This paper presents all of these processes and test results.

A Scheduling Method using Task Partition for Low Power System (저전력 시스템을 위한 BET기반 태스크 분할 스케줄링 기법)

  • Park, Sang-Oh;Lee, Jae-Kyoung;Kim, Sung-Jo
    • The KIPS Transactions:PartA
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    • v.18A no.3
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    • pp.93-98
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    • 2011
  • While the use of battery-powered embedded systems has been rapidly increasing, the current level of battery technology has not kept up with the drastic increase in power consumption by the system. In order to prolong system usage time, the battery size needs to be increased. The amounts of power consumption by embedded systems are determined by their hardware configuration and software for manipulating hardware resources. In spite of that, the hardware provides features for lowering power consumption, if those cannot be utilized efficiently by software including operating system, reduction in power consumption is not optimized. In this paper, we propose a BET(Break Even Time)-based scheduling method using task partition to reduce power consumption of multimedia applications in a mobile embedded system environment.

An Optimal Selection of Embedded Platform for Specific Applications (특정목적 수행을 위한 임베디드 시스템 플랫폼의 최적 선택)

  • Moon, Ho-Sun;Kim, Yong-Deak
    • 전자공학회논문지 IE
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    • v.47 no.1
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    • pp.48-55
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    • 2010
  • The goal of this paper is to determine optimal hardware platform for specific applications. In order to develop an understanding of how select the optimal platform, we focus upon the real-time embedded vehicle system for processing forward image and sound. In this paper we propose to measure parameters such as instructions, execution cycle, required memory size for program and data by using ARMulator. We have measured three types of processor cores: ARM7, ARM9 and ARM10. The results of the study indicated that the proposed methods could measure the minimal requirements of hardware platform for specific applications. By defining lower limit of hardware specifications in embedded systems, we can minimize expenses with suitable system performance without implementing the system.

The development of RTOS technique for designing the controller of DSC/NBDP system (DSC/NBDP시스템의 제어기설계를 위한 실시간 운영체제 기술 개발)

  • 이헌택
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.3
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    • pp.547-553
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    • 2004
  • Linux is the one of various RTOS, also embedded linux has being studied with focus on technical stability and commercial utilities. In this paper, the technical trial was discussed on the development of real-time operating system that provides real time capability and extends the network communications ability and would be applied to the maritime mobile communication system through analysis the embedded linux kernel. Some techniques for Analyzing the embedded linux kernel and designing the target board, making the kernel image and porting the kernel are summarized in this paper.

Real-Time System Parallel Testing Techniques for Weapon System Error Verification (무기체계 오류 검증을 위한 실시간 시스템 병렬시험 기법)

  • Kim, Dong-Jun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.11
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    • pp.130-138
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    • 2016
  • In this paper present the real-time system parallel testing techniques for weapon systems error verification. Previously field testing equipment in the military field was using the sequential testing method to maintain. This method could not check the error verification of interference. For this reason, in this paper propose the real-time system parallel testing techniques using an embedded module instead of the sequential testing techniques which is used in the weapon system error verification. Using the embedded module mounted switching control card conduct the parallel testing and then send the result to the PC. This method is possible to increase the reliability in the weapon system error verification.