• Proceedings of the Korean Information Science Society Conference
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• 2002.10c
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• pp.418-420
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• 2002

실시간 운영 체제(Real-Time OS)는 특정 태스크가 정해진 시간 안에 수행될 수 있도록 시간 결정성(Determinism)을 보장하는 운영 체제이다. 실시간 운영체제는 멀티태스킹(Multitasking) 및 ITC(InterTask Communication 혹은 IPC, Interprocess Communication)을 제공한다는 점에서는 일반 운영체제인 Unix$^{TM}$, Linux$^{TM}$, Windows$^{TM}$ 등과 같지만, 시간 결정성을 보장한다는 점에서 일반 운영체제와 다르다. 본 논문에서는 전부 혹은 일부의 소스 공개를 고려한 개방형 구조를 기반으로 하여, 응용프로그램 개발자에게 보다 나은 융통성과 편의를 제공할 수 있도록 실시간 운영체제 커널을 설계한 내용을 설명하고 있다.

• Journal of Internet Computing and Services
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• v.22 no.3
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• pp.37-43
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• 2021

In this paper, we study how objects from front and back cameras can be recognized in real time in a mobile environment to segment regions of object pixels and synthesize them through image processing. To this work, we applied DeepLabV3 machine learning model to dual cameras provided by Apple's iOS. We also propose methods using Core Image and Core Graphics libraries from Apple for image synthesis and postprocessing. Furthermore, we improved CPU usage than previous works and compared the throughput rates and results of Depth and DeepLabV3. Finally, We also developed a camera application using these two methods.

• Korea Information Processing Society Review
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• v.5 no.4
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• pp.99-107
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• 1998

• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.2
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• pp.365-375
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• 2019

A PLC (Programmable Logic Controller) is a highly-reliable industrial digital computer which supports real-time embedded control applications for safety-critical control systems. Real-time operating systems such as uC/OS have been used for PLCs and must meet real-time constraints. As PLCs have been widely used for industrial control systems and connected to the Internet, they have been becoming a main target of cyberattacks. In this paper, we propose an execution code sanitizer to enhance the security of PLC systems. The proposed sanitizer analyzes PLC programs developed by an IDE before downloading the program to a target PLC, and mitigates security vulnerabilities of the program. Our sanitizer can detect vulnerable function calls and illegal memory accesses in development of PLC programs using a database of vulnerable functions as well as the other database of code patterns related to pointer misuses. Based on these DBs, it detects and removes abnormal use patterns of pointer variables and existence of vulnerable functions shown in the call graph of the target executable code. We have implemented the proposed technique and verified its effectiveness through experiments.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.1
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• pp.166-171
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• 2003

This paper presents the algorithms and Matlab Toolbox for co-simulation of distributed real-time control system based on OSEK-OS and CAN protocol. This toolbox enables the developers to analyze the timing uncertainty, which is caused by resource sharing including shared memories and networks, and to take the timing uncertainty into consideration in the early design phase. Furthermore, this toolbox helps the developers to model the behaviors of a control system by providing graphical user interface for objects of OSEK-OS and CAN. To prove the feasibility of this toolbox, a vehicle body network system is modeled with this toolbox, and the timing uncertainties are analyzed.

• Proceedings of the Korea Contents Association Conference
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• 2012.05a
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• pp.31-32
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• 2012

최근 스마트폰 및 태블릿의 등장으로 컴퓨터를 들고 다니는 시대가 왔다. 웨어러블 컴퓨터는 이를 뛰어넘어 컴퓨터를 몸에 부착해 활동하면서 정보를 처리한다. 이러한 웨어러블 컴퓨터는 극히 전력과 메모리 같은 하드웨어의 제약 사항을 극복하고 사용자 서비스의 QoS를 제공하기 위해 초소형이면서 저전력 기능을 갖춘 실시간 운영체제를 사용해야만 한다. 본 논문에서는 웨어러블 컴퓨터를 위한 실시간 운영체제인 SenOS을 위한 장치전력관리 기법을 설계 및 구현하였다. WPN Protocol을 이용한 통신 프로그램을 실험하여 약 25%의 전력 소모 감축효과를 확인하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05a
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• pp.439-442
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• 2003

본 논문에서는 MPC860T 프로세서에 기반한 내장형 시스템에 실시간 운영체제 uC/OS를 이식한다. 실시간 운영체제는 외부에서 발생한 요구에 대하여 제한된 시간 내에 빨리 처리할 수 있게 하고, 여러 작업이 동시에 수행될 수 있도록 하여, 시스템이 보다 능률적이고 효과적인 성능을 발휘하도록 한다. 또한 부트 로더 PPCBoot를 이식하여 보다 편리한 사용자 환경을 구축한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.49-50
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• 2009

본 논문에서는 국산 임베디드 프로세서인 Core-A에서 동작하는 실시간 운영체제 이식에 대해 설명한다. 운영체제 이식을 위해서는 코드 작성에 앞서 컴파일과 디버깅을 위한 개발 환경을 구축하고 운영체제 이식을 위해 새로 작성할 부분을 파악할 필요가 있다. 이식할 운영체제인 MicroC/OS-II는 교육용으로 널리 쓰이는 실시간 운영체제로 C와 Assembly로 작성되어 있으며, 프로세서에 독립적인 코드와 프로세서에 의존적인 코드가 분리되어 있어 이식이 용이하다. Core-A로의 운영체제 이식은 Context Switching이나 Critical Section과 같이 레지스터를 직접 다루어야 하는 프로세서에 의존적인 코드를 수정하여 이루어졌다

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.10
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• pp.791-798
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• 2018

The CFAR algorithm is mainly used for target detection in radar systems. In particular, OS CFAR is used in a non-uniform noise environment. However, it requires a large amount of computation, because it should sort reference cells in ascending order. This makes it difficult to apply the radar system in real time. In this paper, we describe how to reduce the computational burden of OS CFAR. We compared the power of the test cell and reference cell to determine only the presence or absence of target detection. The common reference cells overlapping in the reference cells of the three test cells are obtained. We first compare the test cell with the highest power value among the three test cells to the common reference cells. Next, we compare each test cell to general reference cells, excluding the common reference cells. The computation time is shortened by reducing the power comparison computation amounts.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.5
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• pp.275-281
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• 2012

A streaming service is considered as an important fact to listen musics at mobile device in the popular smart-phone era. An apple's HTTP Live Streaming method is used in iOS and a RTSP(Real-time Streaming Protocol) method is used in Android OS. A Wowza Media Sever will be used to support both apple and android mobile streaming. This paper describes a design and implementation of smart-phone app. to record user's songs by userself with smart-phone recording function, upload to the streaming server and to service real-time mobile streaming play for an user's selected song and provide song sharing SNS functions.