• Title/Summary/Keyword: Real-time Application

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Scheduling of Sporadic and Periodic Tasks and Messages with End-to-End Constraints (양극단 제약을 갖는 비주기, 주기 태스크와 메시지 스케줄링)

  • Oh Hoon;Park Hong Seong;Kim Hyoung Yuk
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.2
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    • pp.175-185
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    • 2005
  • The scheduling methods of the distributed real-time systems have been proposed. However, they have some weak points. They did not schedule both sporadic and periodic tasks and messages at the same time or did not consider the end-to-end constraints such as precedence relations between sporadic tasks. This means that system scheduling must guarantee the constraints of practical systems and be applicable to them. This paper proposes a new scheduling method that can be applied to more practical model of distributed real-time systems. System model consists of sporadic and periodic tasks with precedence relations and sporadic and periodic messages and has end-to-end constraints. The proposed method is based on a binary search-based period assignment algorithm, an end-to-end laxity-based priority assignment algorithm, and three kinds of schedulability analysis, node, network, and end-to-end schedulability analysis. In addition, this paper describes the application model of sporadic tasks with precedence constraints in a distributed real-time system, shows that existing scheduling methods such as Rate Monotonic scheduling are not proper to be applied to the system having sporadic tasks with precedence constraints, and proposes an end-to-end laxity-based priority assignment algorithm.

The application of open system architecture in power SCADA system (전력감시제어설비(SCADA)의 open system architecture 적용)

  • 이용해;문국연;박장범
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.992-995
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    • 1996
  • The major roles of Power SCADA System are continuous monitoring of electrical equipments state, real-time data processing and dispatching. Especially, SCADA system demands fast response time in heavy load condition, high reliability, fault tolerance, expansion capacity for the future. According to developing computer system technology, SCADA system is changing system configuration from centralized processing system to distributed processing system. This paper describes operational benefits, problems and improvement (which is studying in theory) in the application of Open System Architecture SCADA which has been installed since 1994, Seoul regional control center in KEPCO.

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Optimal regulator applied to rotary shearing system

  • Kotera, Yoshikazu;Itoh, Nobuyuki
    • 제어로봇시스템학회:학술대회논문집
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    • 1987.10a
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    • pp.759-764
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    • 1987
  • The design and application of optimal control technique to the rotary shearing system is mentioned in this paper. To maximize the accuracy in both shearing length and blade speed at shearing, time-varying gain patterns for closed loop control are designed on the basis of fixed terminal time constrained optimal regulator. The performance accuracy in real application has greatly improved than the conventional way of shearing control.

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Ultrasonic Sensor Controlled Sprayer for Variable Rate Liner Applications (초음파센서를 이용한 변량제어 스프레이어)

  • Jeon, Hong-Young;Zhu, Heping
    • Journal of Biosystems Engineering
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    • v.36 no.1
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    • pp.15-22
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    • 2011
  • An experimental variable rate nursery sprayer was developed to adjust application rates for canopy volume in real time. The sprayer consisted of two vertical booms integrated with ultrasonic sensors, and variable rate nozzles coupled with pulse width modulation (PMW) based solenoid valves. A custom-designed microcontroller instructed the sensors to detect canopy size and occurrence and then controlled nozzles to achieve variable application rates. A spray delivery system, which consisted of diaphragm pump, pressure regulator and 4-cycle gasoline engine, offered the spray discharge function. Spray delay time, time adjustment in spray trigger for the leading distance of the sensor, was measured with a high-speed camera, and it was from 50 to 140 ms earlier than the desired time (398 ms) at 3.2 km/h under indoor conditions. Consequently, the sprayer triggered 4.5 to 12.5 cm prior to detected targets. Duty cycles of the sprayer were from 20 to 34 ms for senor-to-canopy (STC) distance from 0.30 to 0.76 m. Outdoor test confirmed that the nozzles were triggered from 290 to 380 ms after detecting tree canopy at 3.2 km/h. The spray rate of the new sprayer was 58.4 to 85.2% of the constant application rate (935 L/ha). Spray coverage was collected at four areas of evergreen canopy by water sensitive papers (WSP), and ranged from 1.9 to 41.1% and 1.8 to 34.7% for variable and constant rate applications, respectively. One WSP area had significant (P < 0.05) difference in mean spray coverage between two application conditions.

A site application of the internet based monitoring system (인터넷기반 계측관리 시스템의 현장적용사례)

  • 이동현;김병희;한병원;김성욱
    • Proceedings of the Korean Geotechical Society Conference
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    • 2003.03a
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    • pp.781-788
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    • 2003
  • It is an essential process to predict behaviors of ground and structure to seek economical efficiency and stability on the given environment. Predictions are conducted through analysis process of ground and structure. For these analyses, exact and quick acquisition of measuring data is required. But we face many difficulties in data acquisition stages due to the conditions of construction site. Therefore development of a powerful and effective monitoring system that can manage the integration of database and the implementation of measuring process in real time is strongly desired. This article shows an actual example of application of internet based monitoring system compared with the conventional monitoring system.

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Indoor Gas Monitoring System Using Smart Phone Application (스마트폰 어플리케이션을 이용한 실내 가스 모니터링 시스템)

  • Choi, Sung-Yeol;Choi, Jang-Sik;Kim, Sang-Choon
    • Convergence Security Journal
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    • v.12 no.1
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    • pp.49-54
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    • 2012
  • Special applications designed for smart phone, so called "Apps" are rapidly emerging as unique and effective sources of environmental monitoring tools. Using the advantages of Information and Communication Technology (ICT), this paper propose an application that provides Indoor Gas Monitoring System. In this paper, use four wireless gas sensor modules to acquire sensors data wirelessly coupled with the advantages of existing portable smart device based on Android platform to display the real-time data from the sensor modules. Additionally, this paper adapts a simple gas classification algorithm to inform in-door Gas for users real-time based.

Control and Development of LonWorks Intelligent Control Module for Water Treatment Facility Based Networked control System

  • Hong, Won-Pyo;Kim, Dong-Hwa
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1757-1762
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    • 2003
  • With distribution industrial control system, the use of low cost to achieve a highly reliable and safe system in real time distributed embedded application is proposed. This developed intelligent node is based on two microcontrollers, one for the execution of the application code, also as master controller for ensuring the real time control & the logic operation with PLD and other for communication task and the easy control execution, i.e., I/O digital input, digital output and interrupting. This paper also presents where the case NCS (Networked control system) with LonTalk protocol is applied for the filtration process control system of a small water treatment plant.

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A Study on Real-Time Vision-Based Detection of Skin Pigmentation

  • Yang, Liu;Lee, Suk-Hwan;Kwon, Seong-Geun;Kwon, Ki-Ryong
    • Journal of Multimedia Information System
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    • v.1 no.1
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    • pp.77-85
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    • 2014
  • Usually, the skin pigmentation detection and diagnosis are made by clinicians. In this process it is subjective and non-quantitative. We develop an approach to detect and measure the different pigmentation lesions base on computer vision technology. In the paper we study several usually used skin-detecting color space like HSV, YCbCr and normalized RGB. We compare their performance with illumination influence for detecting the pigmentation lesions better. Base on a relatively stable color space, we propose an approach which is RGB channels vector difference characteristic for the detection. After the object region detection, we also use the difference to measure the difference between the lesion and the surrounding normal skin. From the experiment results, our approach can effectively detect the pigmentation lesion, and perform robustness with different illumination.

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The Design and Implementation of Java Application in KVM on Real-Time Operating System, iRTOS (실시간 운영체제 iRTOS 상에서의 KVM기반 자바 응용프로그램 설계 및 구현)

  • Lee, jin-wook;Kim, jong-jin;Lee, cheol-hoon
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.833-838
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    • 2009
  • Recently the use of the portable device like a PDA or a Smart-Phone increases to follow, Java technology that support Platform Independence on Hardware Flatform has become core Flatform in Software sphere. Especially Portable device use a KVM(Kilobyte Virtual Machine) of Java's various specification. In this paper, we design and implement Java Game Application for verification of KVM and verify on Real-Time Operating System iRTOS.

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Real-Time Safety Driving Assistance System Based on a Smartphone

  • Kang, Joon-Gyu;Kim, Yoo-Won;Jun, Moon-Seog
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.8
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    • pp.33-39
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    • 2017
  • In this paper, we propose a method which implements warning to drivers through real-time analysis of risky and unexpected driver and vehicle behavior using only a smartphone without using data from digital tachograph and vehicle internal sensors. We performed the evaluation of our system that demonstrates the effectiveness and usefulness of our method for risky and unexpected driver and vehicle behavior using three information such as vehicle speed, azimuth and GPS data which are acquired from a smartphone sensors. We confirmed the results and developed the smartphone application for validate and conducted simulation using actual driving data. This novel functionality of the smartphone application enhances drivers' situational awareness, increasing safety and effectiveness of driving.