• 제목/요약/키워드: a real-time analysis

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원격 실시간 제어 시스템을 위한 정적 프로그램 분석에 의한 보안 기법 (Ensuring Securityllable Real-Time Systems by Static Program Analysis)

  • 임성수
    • 한국컴퓨터정보학회논문지
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    • 제10권3호
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    • pp.75-88
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    • 2005
  • 본 논문에서는 원격으로 제어 가능한 실시간 시스템에서 발생 가능한 악의적인 코드 삽입에 의한 보안 공격을 방지할 수 있는 방법을 제안한다. 제안하는 방법은 원격으로 제어 코드를 전달하여 시스템을 업그레이드하는 경우 전달된 제어 코드의 안전성을 실행 전에 분석하는 방법으로서 정적 프로그램 분석 방법을 이용한다. 제안하는 분석 방법을 구현한 도구를 컴파일러 내에 삽입하여 실제 원격으로 소프트웨어 업그레이드가 가능한 실시간 시스템 환경에 적용하여 효용성을 검증하였다.

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실시간 임베디드 리눅스에서 다양한 주기적 타스크의 실시간 메커니즘 성능 분석 (On Benchmarking of Real-time Mechanisms in Various Periodic Tasks for Real-time Embedded Linux)

  • 고재환;최병욱
    • 로봇학회논문지
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    • 제7권4호
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    • pp.292-298
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    • 2012
  • It is a real-time system that the system correctness depends not only on the correctness of the logical result of the computation but also on the result delivery time. Real-time Operating System (RTOS) is a software that manages the time of a microprocessor to ensure that the most important code runs first so that it is a good building block to design the real-time system. The real-time performance is achieved by using real-time mechanisms through data communication and synchronization of inter-task communication (ITC) between tasks. Therefore, test on the response time of real-time mechanisms is a good measure to predict the performance of real-time systems. This paper aims to analysis the response characteristics of real-time mechanisms in kernel space for real-time embedded Linux: RTAI and Xenomai. The performance evaluations of real-time mechanism depending on the changes of task periods are conducted. Test metrics are jitter of periodic tasks and response time of real-time mechanisms including semaphore, real-time FIFO, Mailbox and Message queue. The periodicity of tasks is relatively consistent for Xenomai but RTAI reveals smaller jitter as an average result. As for real-time mechanisms, semaphore and message transfer mechanism of Xenomai has a superior response to estimate deterministic real-time task execution. But real-time FIFO in RTAI shows faster response. The results are promising to estimate deterministic real-time task execution in implementing real-time systems using real-time embedded Linux.

TCPN을 이용한 실시간 시스템의 스케쥴가능성 분석 및 회복기법 (A Schedulability analysis and Recovery Technique of Real-Time System using TCPN)

  • 김춘배;박흥복
    • 한국정보처리학회논문지
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    • 제6권10호
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    • pp.2797-2808
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    • 1999
  • Timing Constraint Petri Nets(TCPN) extend petri nets by adding timing constraints, it is provide a formal method for the modeling and analysis of real-time system. A real-time schedulability analysis decide that a set of concurrent processes will always meet its deadline. In this paper, we present TCPN model for real-time system include timing constraints and propose a schedulability analysis algorithm using them. Also, When the TCPN model is unscheduleable under the imposed timing constraints, we propose a recovery technique that will be scheduleable by the system specification modifying or timing constraints relaxing in the optimized time.

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기상레이더와 분포형 모형을 이용한 실시간 유출해석 시스템 개발 및 평가 (Development and Evaluation of a Real Time Runoff Modelling System using Weather Radar and Distributed Model)

  • 최윤석;김경탁;김주훈
    • 한국습지학회지
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    • 제14권3호
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    • pp.385-397
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    • 2012
  • 격자 기반의 물리적 분포형 모형은 유역의 물리적 매개변수와 격자 형식의 공간 및 수문자료를 이용해서 유출해석을 수행한다. 본 연구에서는 격자 기반의 물리적 분포형 강우-유출 모형인 GRM(Grid based Rainfall-runoff Model)의 실시간 유출해석 모듈인 GRM RT(Real Time)를 이용해서 실시간 유출해석 시스템을 개발하였다. 실시간으로 수신되는 기상레이더 자료를 기상청의 실시간 AWS 자료를 이용하여 보정한 후 유출해석에 적용하며, 수위관측소 자료로부터 생성되는 유량자료를 이용해서 유출모형을 실시간 보정한다. 본 연구에서는 실시간 유출해석 시스템 구축을 위해서 필요한 데이터베이스를 설계 및 구현하였으며, 분포형 모형과 레이더 자료를 이용한 실시간 유출해석 절차를 정립하였다. 또한 개발된 시스템의 성능을 평가하고 실시간 모형보정에 대한 적용성을 평가하였다. 소양강댐 상류에 위치한 내린천 수위관측소 유역을 대상으로 실시간 유출해석 시스템을 적용하고 그 결과를 평가하였다.

실행시간 예측가능한 실시간 메카니즘 제어언어의 구현기법 (Implementation technique of execution time predictable real-time mechanism control language)

  • 백정현;원유헌
    • 한국통신학회논문지
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    • 제22권6호
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    • pp.1365-1376
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    • 1997
  • In this paper, we designed real time mechanism control language and proposed execution time analysis technique. It was impossible to handle real-time mechanism control programs like programmable controller, numerical controller, distributed control system and robot controller with general purpose programming languages and operating systems because they have to process electric signals generated by thousands of sensors at the same at the same time and in real time. So we made it possible to predict plausibility of time constraint constructs of tiem constraint construct of a real time application program at compilation time by adding time constraint constructs and mechanism synchronization structure to conditional statement and iteration statement of a programming language and developing execution time analysis technique.

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Efficient Anomaly Detection Through Confidence Interval Estimation Based on Time Series Analysis

  • Kim, Yeong-Ju;Jeong, Min-A
    • International journal of advanced smart convergence
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    • 제4권2호
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    • pp.46-53
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    • 2015
  • This paper suggests a method of real time confidence interval estimation to detect abnormal states of sensor data. For real time confidence interval estimation, the mean square errors of the exponential smoothing method and moving average method, two of the time series analysis method, were compared, and the moving average method with less errors was applied. When the sensor data passes the bounds of the confidence interval estimation, the administrator is notified through alarms. As the suggested method is for real time anomaly detection in a ship, an Android terminal was adopted for better communication between the wireless sensor network and users. For safe navigation, an administrator can make decisions promptly and accurately upon emergency situation in a ship by referring to the anomaly detection information through real time confidence interval estimation.

응답 시간 해석 도구를 이용한 실시간 분산 제어 시스템의 시간 해석 (Timing Analysis of Distributed Real-time Control System using Response-time Analysis Tool)

  • 최재범;신민석;선우명호;한석영
    • 한국자동차공학회논문집
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    • 제13권1호
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    • pp.194-203
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    • 2005
  • The process of guaranteeing that a distributed real-time control system will meet its timing constraints, is referred to as schedulability analysis. However, schedulability analysis algorithm cannot be simply used to analyze the system because of complex calculations of algorithm. It is difficult for control engineer to understand the algorithm because it was developed in a software engineer's position. In this paper we introduce a Response-time Analysis Tool(RAT) which provides easy way far system designer to analyze the system by encapsulating calculation complexity. Based on the RAT, control engineer can verify whether all real-time tasks and messages in a system will be completed by their deadline in the system design phase.

Detection of Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp. and Staphylococcus aureus using duplex real-time PCR assay with melting curve analysis on fresh lettuce

  • Lee, Na-Ri;Kwon, Kyung-Yoon;Choi, Sung-Wook;Koo, Min-Seon;Chun, Hyang-Sook
    • 한국식품위생안전성학회지
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    • 제26권2호
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    • pp.114-119
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    • 2011
  • 본 연구에서는 신선편의 채소와 과일에서 주로 검출되는 대장균(E. coli Ol577:H7), 리스테리아(L. monocytogenes), 살모넬라(Salmonella, spp.), 형색포도상구균(S. aureus)을 검출하고 동정할 수 있는 real time PCR 방법을 melting curve 분석을 활용하여 single tube 반응으로 두 종의 식중독균을 동시 검출하는 방법을 개발하고자 하였다. 대장균의 ${\beta}$-glucuronidase (uidA), 황색포도상구균의 thermonuclease (nuc), 리스테리아의 hemolycin (hly), 살모넬라의 tetrahionate reductase (ttr) 를 특이적으로 검출할 수 있는 4종의 프라이머 세트에 대한 real-time PCR의 melting curve 분석을 통하여 황색포도상구균과 대장균 동시분석 시 $T_m$ 값이 $80.6{\pm}0.9^{\circ}C$$86.9{\pm}0.5^{\circ}C$, 리스테리아와 살모넬라 동시분석 시 Tm 값이 $80.4{\pm}0.6^{\circ}C$$88.1{\pm}0.11^{\circ}C$로 확인하였고, 그 결과 정제되어진 각 식중독균의 genomic DNA를 주형으로 한 duplex real-time PCR 방법이 uniplex real-time PCR 방법과 마찬가지로 10 genome equivalents 까지 검출할 수 있는 민감도를 나타내었다. 또한, 양배추에 네 종의 식중독균을 접종하고, 증균배양 없이 DNA를 추출하여 duplex real-time PCR 을 수행한 결과 모든 식종목균에서 $10^3$ CFU/g의 검출 한계를 나타내었다. 결과적으로 개발된 melting curve 분석을 이용한 duplex real-time PCR 방법은 식품안전 증진을 위한 시간, 노동력, 비용 절감에 있어서 유효한 방법이 될 것으로 판단된다.

A Study on Real-time Graphic Workflow For Achieving The Photorealistic Virtual Influencer

  • Haitao Jiang
    • International journal of advanced smart convergence
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    • 제12권1호
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    • pp.130-139
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    • 2023
  • With the increasing popularity of computer-generated virtual influencers, the trend is rising especially on social media. Famous virtual influencer characters Lil Miquela and Imma were all created by CGI graphics workflows. The process is typically a linear affair. Iteration is challenging and costly. Development efforts are frequently siloed off from one another. Moreover, it does not provide a real-time interactive experience. In the previous study, a real-time graphic workflow was proposed for the Digital Actor Hologram project while the output graphic quality is less than the results obtained from the CGI graphic workflow. Therefore, a real-time engine graphic workflow for Virtual Influencers is proposed in this paper to facilitate the creation of real-time interactive functions and realistic graphic quality. The real-time graphic workflow is obtained from four processes: Facial Modeling, Facial Texture, Material Shader, and Look-Development. The analysis of performance with real-time graphical workflow for Digital Actor Hologram demonstrates the usefulness of this research result. Our research will be efficient in producing virtual influencers.

차량 시뮬레이터 접목을 위한 실시간 인체거동 해석기법 (Real-Time Analysis of Occupant Motion for Vehicle Simulator)

  • 오광석;손권;최경현
    • 대한기계학회논문집A
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    • 제26권5호
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    • pp.969-975
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    • 2002
  • Visual effects are important cues for providing occupants with virtual reality in a vehicle simulator which imitates real driving. The viewpoint of an occupant is sensitively dependent upon the occupant's posture, therefore, the total human body motion must be considered in a graphic simulator. A real-time simulation is required for the dynamic analysis of complex human body motion. This study attempts to apply a neural network to the motion analysis in various driving situations. A full car of medium-sized vehicles was selected and modeled, and then analyzed using ADAMS in such driving conditions as bump-pass and lane-change for acquiring the accelerations of chassis of the vehicle model. A hybrid III 50%ile adult male dummy model was selected and modeled in an ellipsoid model. Multibody system analysis software, MADYMO, was used in the motion analysis of an occupant model in the seated position under the acceleration field of the vehicle model. Acceleration data of the head were collected as inputs to the viewpoint movement. Based on these data, a back-propagation neural network was composed to perform the real-time analysis of occupant motions under specified driving conditions and validated output of the composed neural network with MADYMO result in arbitrary driving scenario.