• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.6
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• pp.863-872
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• 2002

Real-time(RT) object-oriented(00) distributed computing is a form of RT distributed computing realized with a distributed computer system structured in the form of an object network. Several approached proposed in recent years for extending the conventional object structuring scheme to suit RT applications, are briefly reviewed. Then the approach named the TMO(Time-triggered Message-triggered Object) structuring scheme was formulated with the goal of instigating a quantum productivity jump in the design of distributed time triggered simulation. The TMO scheme is intended to facilitate the pursuit of a new paradigm in designing distributed time triggered simulation which is to realize real-time computing with a common and general design style that does not alienate the main-stream computing industry and yet to allow system engineers to confidently produce certifiable distributed time triggered simulation for safety-critical applications. The TMO structuring scheme is a syntactically simple but semantically powerful extension of the conventional object structuring approached and as such, its support tools can be based on various well-established 00 programming languages such as C++ and on ubiquitous commercial RT operating system kernels. The Scheme enables a great reduction of the designers efforts in guaranteeing timely service capabilities of application systems.

• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.101-113
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• 2018

Systems such as military inspection equipment which it is important to acquire and evaluate data in real-time should be able to real-time processing at the operating system level. As technology advances, there is a demand for replacing existing equipment with mobile device, but mobile devices with Android are not suitable for systems requiring real-time performance. On Android, garbage collection ensures free memory, while other tasks are interrupted while this task is performed, which cannot guarantee periodicity of particular tasks. In this paper, we designed and implemented a structure to control execution garbage collection of Android to solve this problem. Real-time performance is ensured by controlling garbage collection during the time required for real-time operation, and RTiK(Real-Time implanted Kernel) is applied to ensure real-time performance on Android. In order to evaluate the performance, we measured the call period of the 5ms period task, and, only 34.31% of the task was guaranteed before the control, but the task period of 98.18% was satisfied through control, providing real-time performance to Android.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.13-20
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• 2014

In this paper, we implemented the object scanning with nxtOSEK which is an open source platform. nxtOSEK consists of device driver of leJOS NXJ C/Assembly source code, TOPPERS/ATK(Automotive real time Kernel) and TOPPERS/JSP Real-Time Operating System source code that includes ARM7 specific porting part, and glue code make them work together. nxtOSEK can provide ANSI C by using GCC tool chain and C API and apply for real-time multi tasking features. We experimented the 3D scanning with ultra sonic and laser sensor which are made directly by laser module diode and experimented the measurement of scanning the object by knowing x, y, and z coordinates for every points that it scans. In this paper, the laser module is the dimension of $6{\times}10[mm]$ requiring 5volts/5[mW], and used the laser light of wavelength in the 650[nm] range. For detecting the object, we used the beacon detection algorithm and as the laser light swept the objects, the photodiode monitored the ambient light at interval of 10[ms] which is called a real time. We communicated the 3D scanning platform via bluetooth protocol with host platform and the results are displayed via DPlot graphic tool. And therefore we enhanced the functionality of the 3D scanner for identifying the image scanning with laser sensor modules compared to ultra sonic sensor.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2005.11a
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• pp.117-120
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• 2005

A Digital Broadcasting Satellite (DBS) receiver converts digital A/V streams received from a satellite to analog NTSC A,/V signals in real-time. Multi-tasking is an efficient way to improve the utilization of the processor core in real-time applications. In this paper, we propose a hybrid approach with a balanced trade-off between hardware kernel and multi-tasking programming to increase a system throughput. First, the schedulability of the critical hard real-time tass in the DBS receiver is verified by using a simple feasibility test. Then. several soft real-time tasks are thoughtfully programmed to satisfy functional requirements of the system.

• Proceedings of the Korea Contents Association Conference
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• 2011.05a
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• pp.17-18
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• 2011

최근 빠른 응답성과 정확성을 요구하는 임베디드 시스템의 사용이 증가됨에 따라 임베디드 시스템의 시간 정확성을 만족 시키는 경성 실시간성의 중요성이 커지고 있다. 이러한 임베디드 시스템의 운영체제로는 응용프로그램 개발의 편의성을 위해 범용 운영체제인 Linux를 많이 사용하며, Linux에 실시간성 제공을 위해 RT-Linux(Real Time - Linux)를 사용하고 있다. RT-Linux의 경우 경성 실시간성을 제공하지만 어셈블러를 사용해야 하므로 개발자가 다루기 힘들다는 단점이 존재한다. 이에 따라 Linux에 경성 실시간성을 제공하고 개발자에게 개발의 편의성을 제공하는 방법에 대한 연구가 필요하다. 본 논문에서는 범용운영체제인 Linux에 경성 실시간성을 제공하기 위해 x86기반의 Window에 실시간성을 제공하는 RTiK(Real-Time implanted Kernel)을 Linux에 모듈 형태로 적재하여 실시간성을 제공할 수 있는 방법을 설계 및 구현하였다.

• IEMEK Journal of Embedded Systems and Applications
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• v.11 no.4
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• pp.251-257
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• 2016

The multi-core technology has become pervasive in embedded systems. An implementation of the Doppler Beam Sharpening algorithm that improves the azimuth resolution by using doppler frequency shift is possible only in multi-core environment because of the amount of calculation. In this paper, we design of multi-core architecture for a real time implementation of DBS algorithm. And based on designed structure, we produce a DBS image on P4080 board.

• Proceedings of the Korean Society of Computer Information Conference
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• 2012.01a
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• pp.25-28
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• 2012

네트워크 및 통신 기술의 발전에 따라 임베디드 시스템은 정보통신 기술 및 유무선 네트워크 기술을 적극 수용하면서, 지능형 정보 시스템의 핵심으로 성장하고 있으며, 시리얼 통신은 이러한 임베디드 시스템에서 사용되는 통신 시스템의 일종이다. 윈도우즈 운영체제는 개발환경의 편의성 및 호환성 때문에 임베디드 시스템에서 많이 사용되는 운영체제이다. 하지만 윈도우즈 운영체제는 실시간성을 제공하지 않으며, 윈도우 시스템에서 사용하는 시리얼 통신도 실시간성을 보장하지 못한다. 본 논문에서는 윈도우즈에 디바이스 드라이버 형태로 이식되어 유저 영역에 실시간성을 지원하는 이벤트 기반 RTiK(Real Time implanted Kernel)을 사용하여 시리얼 통신에 실시간성을 지원 할 수 있는 방법을 설계 및 구현하였다.

• The KIPS Transactions:PartA
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• v.8A no.1
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• pp.1-8
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• 2001

This paper describes the design and implementation of C standard library for real-time operating system Q+, that is being developed for the internet appliance. The C library in the real-time operating system should be defined according to the standard interface and support the concurrent execution of threads. The implemented C standard library is reentrant and follows POSIX.l standard interface. And, the C standard library functions, which are adequate to the Q+ application and commonly provided by commercial real-time operating systems, are selected among POSIX.l standard functions. The C standard library is implemented on the Q+ kernel and D-TV set-top box according to the implementation sequence, which is determined by analyzing the relation of function calls.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.5
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• pp.1151-1160
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• 2016

A TrustZone-based rootkit detecting solution using a secure timer ensures the integrity of monitoring system, because ARM TrustZone technology provides isolated environments from a monitored OS against intercepting and modifying invoke commands. However, it is vulnerable to transient attack due to periodic monitoring. Also, Address Translation Redirection Attack (ATRA) cannot be detected, because the monitoring is operated by using the physical address of memory. To ameliorate this problem, we propose a snoop-based kernel introspection system. The proposed system can monitor a kernel memory in real-time by using a snooper, and detect memory-bound ATRA by introspecting kernel pages every context switch of processes. Experimental results show that the proposed system successfully protects the kernel memory without incurring any significant performance penalty in run-time.

• Journal of Korea Multimedia Society
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• v.20 no.2
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• pp.363-370
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• 2017

Data assimilation is an initializing method for air quality forecasting such as PM10. It is very important to enhance the forecasting accuracy. Optimal interpolation is one of the data assimilation techniques. It is very effective and widely used in air quality forecasting fields. The technique, however, requires too much memory space and long execution time. It makes the PM10 air quality forecasting difficult in real time. We propose a fast optimal interpolation data assimilation method for PM10 air quality forecasting using a new kernel tridiagonal sparse matrix and CUDA massively parallel processing architecture. Experimental results show the proposed method is 5~56 times faster than conventional ones.