• Proceedings of the KIEE Conference
• /
• 1999.11c
• /
• pp.512-514
• /
• 1999

The damping ratio $\zeta$ of a continuous 2nd order response which passes all the points of the discrete response of a 2nd order discrete system(envelope curve) is a function of only the location of the closed-loop pole and ie not at all related to the location of the zero. And the peak overshoot of the envelope curve is uniquely specified by the damping ratio $\zeta$, which is a function of solely the closed-loop pole location, and the angle $\alpha$ which is determined by the relative location of the zero with respect to the closed-loop complex pole. Therefore, if the zero slides on the real axis with the closed-loop complex poles being fixed, then the angle $\alpha$ changes however the damping ratio $\zeta$ does not. Accordingly, when the closed-loop system poles are fixed, the peak overshoot is function of $\alpha$ or the system zero. In this thesis the effects of the relative location of the zero on the system performance of a second order discrete system is studied.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.2
• /
• pp.93-99
• /
• 2016

In this paper, higher order coupler using small size waveguide which applicable for mobile Ku-band multimode monopulse satellite tracking antenna system, has been designed, implemented and tested. Proposed higher order mode coupler adopts a coaxial structure for low profile characteristic considering installation property to mobile satellite terminal system. In addition, by using proposed coupler, extracted tracking error signal pattern has measured and confirmed that required tracking accuracy is satisfied in desired frequency band. In the future, proposed coupler could utilize for multimode monopulse satellite tracking system for high tracking accuracy.

• Journal of Multimedia Information System
• /
• v.1 no.2
• /
• pp.95-100
• /
• 2014

Variable message signs (VMS) have the different sizes and a specific type according to the city scene and it has to be displayed by different message on the display panel in real-time. And VMS manufacturers must produce the different products in order to give a customized product to each order. In addition that, they should test and check the correct operation to each VMS product using the different message frame. That is very time and workers consuming and VMS emulator with an automatic variable message generator system is necessary. Also, the automatic message generator system is needed to real-time scheduling in order to display the message on the VMS panel like real world. In this paper, we design and implement the VMS emulator embedded the automatic message frame generator system with real-time scheduling which can set several parameters easily on the windows dialog.

• Journal of Institute of Control, Robotics and Systems
• /
• v.17 no.7
• /
• pp.634-640
• /
• 2011

When a servo position controller of a robot or a driving units is composed of a PID controller, servomechanism which is modelled is composed of current, velocity and position control loops. After this model is simulated, the technique operating gain of each controller is suggested. The model consists of current, velocity and position controllers from the inside to the outside gradually. Also, to combine velocity and position controllers with 2 order system, simulation is performed after current controllers are composed, which are able for current loop to work ideally. If a current controller is treated with constant, it is possible for velocity and position controller to consist of controller into 2 order system. The technique is verified by applying T-company servo motor which is much more applied to current, velocity and position controller robots.

• Journal of Korean Institute of Industrial Engineers
• /
• v.42 no.2
• /
• pp.151-164
• /
• 2016

In this paper, we deal with a risk analysis for an IPS (Integrated power system) and propose a simulation model combining the fault tree and event tree in order to estimate the system availability and risk level, together. Firstly, the basic information such as operational scenarios, physical structure, safety systems is explained in order to make the fault tree and event tree of the IPS. Next, we propose a discrete-event simulation model using a next-event time advance technique to advance the simulation time. Also the state transition and activity diagrams are explained to represent the relationship between the objects. By numerical examples, the redundancy allocation is considered in order to decrease the risk level of the IPS.

• Journal of the Korea Safety Management & Science
• /
• v.4 no.2
• /
• pp.147-154
• /
• 2002

An Order Management System related to press die fabrication in automobile industry are developed in this research. This system is constructed by CORBA and XML to avoid disorder from data integration. Because CORBA can integrate diverse applications within distributed heterogeneous environments and XML can be made use of data exchange format, The developed system is available on almost any hardware platforms, operation system environments, and programming languages.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.10 no.2 s.48
• /
• pp.21-29
• /
• 2006

It is impractical to install sensors on every floor of a tall building to measure the full state vector because of the large number of degrees of freedom. This makes it necessary to introduce reduced order control. A kind of system reduction scheme (dynamic condensation method) is proposed in this paper. This method is iterative and Guyan condensation is looked upon as an initial approximation of the iteration. Since the reduced order system is updated repeatedly until a desired one is obtained, the accuracy of the reduced order system resulting from the proposed method is much higher than that obtained from the Guyan condensation method. An eigenvalue shilling technique is applied to accelerate the convergence of Iteration. Two schemes to establish the reduced order system by using the proposed method are also presented and discussed in this paper. The results for a tail building with active tuned mass damper show that the proposed method is efficient for the reduced order modelling and the accuracy is very close to exact only after two iterations.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.2
• /
• pp.443-451
• /
• 2015

The stability of a multi-terminal direct current (MTDC) system is often influenced by its control strategy. To improve the stability of the MTDC system, the control strategy of the MTDC system must be appropriately adopted. This paper deals with estimating stability of a MTDC system based on the line-commutated converter based high voltage direct current (LCC HVDC) system with an inverter with constant extinction angle (CEA) control or a rectifier with constant ignition angle (CIA) control. In order to evaluate effects of two control strategies on stability, a MTDC system is tested on two conditions: initialization and changing DC power transfer. In order to compare the stability effects of the MTDC system according to each control strategy, a mathematical MTDC model is analyzed in frequency domain and time domain. In addition, Bode stability criterion and transient response are carried out to estimate its stability.

• International Journal of Computer Science & Network Security
• /
• v.24 no.2
• /
• pp.169-177
• /
• 2024

Interacting Spherical tank has maximum storage capacity is broadly utilized in industries because of its high storage capacity. This two tank level system has the nonlinear characteristics due to its varying surface area of cross section of tank. The challenging tasks in industries is to manage the flow rate of liquid. This proposed work plays a major role in controlling the liquid level in avoidance of time delay and error. Several researchers studied and investigated about reducing the nonlinearity problem and their approaches do not provide better result. Different types of controllers with various techniques are implemented by the proposed system. Intelligent Adaptive Neuro Fuzzy Inference System (ANFIS) based Sliding Mode Controller (SMC) with Fractional order PID controller is a novel technique which is developed for a liquid level control in a interacting spherical tank system to avoid the external disturbances perform better result in terms of rise time, settling time and overshoot reduction. The performance of the proposed system is obtained by analyzing the simulation result obtained from the controller. The simulation results are obtained with the help of FOMCON toolbox with MATLAB 2018. Finally, the performance of the conventional controller (FOPID, PID-SMC) and proposed ANFIS based SMC-FOPID controllers are compared and analyzed the performance indices.

• Journal of the Korea Institute of Building Construction
• /
• v.2 no.2
• /
• pp.175-180
• /
• 2002

"Samsung Composite Shear Wall System" has its basis on "Samung Able System". "Samsung Able System" has some problems not only in the connection structure but also in waterproofing and soundproofing. We developed "Samsung Composite Shear Wall System" in order to solve these matters and expand PC system. "Samsung Composite Shear Wall System" is the compromise and complement of all the merits of full PC, half PC and in-situ concrete system.