• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1048-1051
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• 1996

In this paper, we present real-time S/W architecture and techniques such as real-time scheduling, synchronization, and etc. for implementation of a real-time control system for driving multi-motors. Simulation shows feasibility of real-time S/W techniques presented here.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.191-191
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• 2000

Hydraulic servo system is difficult to be made up and each component is very expensive, it takes long for actual system to make and test and it costs a high price. Because of these characteristics of hydraulic servo system, a real time simulator that could describe behavior of real system is highly demanded, without composing real hydraulic system. So, many studies have been (lone on these subjects and many simulators are developed with superiority. Since the nonlinearity of a hydraulic system common simulator have composed of many calculative times byusing DSP(Digital Signal processing) and have made it possible to find the situations of the system in real time, calculating hydraulic simulation and controller separately. In this study, we suggest real-time simulator that could describe real system without ordinary DSP card. This simulator is composed of 80196kc and personal computer. DSP card that has calculated complex numerical equation is supplanted by personal computer and 80196kc generates control signals independently out of the personal computer. In all process, personal computer is synchronized with one-board microprocessor within sampling time in the closed loop system. This makes it possible to be described in hydraulic servo system in real time. And to make a comparison between the result of the real-time simulator and a hydraulic servo system.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.336-338
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• 2006

One of the important topics concerning the safety of electrical and electronic system is the reliability of the wiring system. The Time-Frequency Domain Reflectometry(TFDR) is a state-of-the-art system for detection and estimation of the fault on a wiring/cable. The purpose of this paper is to implement a Labview based TFDR Real Time system though the instruments of PCI extensions for Instrumentation(PXI). The TFDR Real Time system consists of the five parts: Reference signal design, signal generation, signal acquisition, algorithm execution, results diplay part. In the signal generation and acquisition parts we adopt the Arbitrary Waveform Generator(AWG) and Digital Storage Oscilloscope(DSO) PXI modules which offer commonality, compatibility and easy integration at low cost. And execution of the PXI modules not only is controlled by the Labview programing but also the total system process is executed by the Labview application software.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.10
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• pp.678-689
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• 2004

The major concern of networked control system is network uncertainties such as time delay and data loss. Because these uncertainties may degrade the performance of networked control system and destabilize the entire system. Therefore, the performance and the stability variation of networked control system due to network uncertainties must be considered first in designing networked control system. In particular, the stability analysis of networked control system is most important issue since time delay and data loss can make the overall systems unstable. In this paper, we present a new stability analysis method of networked control system with time delay and data loss, which is impossible in previous works. The proposed method can determine maximum time delay and allowable transmission rate that preserve stability performance of networked control system. The results of the simulation validate effectiveness of our stability analysis method.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.223-223
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• 2000

Embedded system area has brought an innovation and has been spread rapidly by the growth of the Internet, wireless telephony and multimedia recently. Many embedded systems are required to be real-time systems in that it needs multi-tasking and priority based scheduling. This paper introduces a real-time system that was developed with web server ability for control and monitoring system employing a real-time operating system. It discusses the design model, structure, and applications of web server system. We used SNDS100 board which has a 32-bit RISC microcontroller of ARM7TDMI core as a hardware platform. MicroC/OS kernel was used as Real-time operating system that supports a preemptive and multitasking functions. We developed a hierarhchical control and monitoring system that not only reduced system and management costs, but also enhanced reusability and portability.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.4
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• pp.638-647
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• 1994

This paper describes the real time Hardware-In-the Loop Simulation(HILS) that is an efective tool for design, testing and performance evaluation of the guidanc eflight system. The real time HILS was performed by using a 3-axis flight motion simulator, real time computer, I/O system and flight control system hardware along with the assumed flight trajectory of the guidance flight system. Also, we proved the validity of the real time HILS is the guidance flight system by comparing its simulation results with the software simulation data and telemetry data.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.796-801
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• 2005

Time management is one of the critical tasks in project management. Based on the theories of total quality management, this authors presented a project time management method, total time management (TTM), so as to facilitate highway project time management. This paper discussed the four fundamental characteristics of TTM: total factors management, staff management, project life cycle management, and Plan-Do-Check-Action (PDCA) cycle management. Now, most managers use computer software to manage the project. In order to make the theory of TTM more executable, the authors develop a project time management system suitable for TTM. This paper presents this time management system's analysis processes including system requirement, key functions etc..

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.04a
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• pp.49-56
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• 1993

We consider a B/G/1 queueing system with vacations, where the server closes the gate when it begins a vacation. In this system, customers arrive according to a Bernoulli process. The service time and the vacation time follow discrete distributions. We obtain the distribution of the number of customers at a random point in time, and in turn, the distribution of the residence time (queueing time + service time) for a customer. This system finds an application in the performance evaluation of the DQDB protocol which has been adopted as the standard protocol for IEEE 802.6 MAN.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.2
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• pp.194-200
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• 2006

The SoC and digital technology development recently enabled the emergence of information devices and control devices because the SoC presents many advantages such like lower power consumption, greater reliability, and lower cost. However, it is nearly impossible to use the SoC without operating systems because the SoC is included with many peripherals and complex architecture. It is required to use embedded operating systems and real-time operating systems may be used as an embedded operating system. So far, real-time operating systems are widely used to implement a Real-Time system since it meets developer's requirements. However, real-time operating systems have disadvantages including a lack of standards, expensive development, and license. Embedded Linux is able to overcome their disadvantages. In this paper, the implementation of control system platform for a mobile robot using real-time Embedded Linux is described. As a control hardware system platform, XScale board is used. As the real-time Embedded Linux, RTAI is adopted which is open source and royalty free, and supports various architectures and real-time devices, such like real-time CAN and real-time COM. This paper shows the implementation of RTAI on XScale board that means the porting procedure. We also applied the control system platform to the mobile robot and compared the Real-Time serial driver with non real-time serial driver. Experimental results show that that using RTAI is useful to build real-time control system with powerful functionalities of Linux.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.3
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• pp.21-28
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• 2016

File Time information has a significant meaning in digital forensic investigation. File time information in Linux Ext4 (Extended File System 4) environment is the Access Time, Modification Time, Inode Change Time, Deletion Time and Creation Time. File time is variously changed by user manipulations such as creation, copy and edit. And, the study of file time change is necessary for evidence analysis. This study analyzes the change in time information of files or folders resulting from user manipulations in Linux operating system and analyzes ways to determine real time of malware infection and whether the file was modulation.