• Journal of the Korea Society for Simulation
• /
• v.20 no.4
• /
• pp.49-58
• /
• 2011

It is required that a developed control system should be verified using simulator in terms of functionality and reliability prior to application to a power plant that is a very critical facility in the industry. In this paper, the control model for turbine bypass system was developed for power plant simulator. In order to develop the control model for turbine bypass system, the tool that can be used to implement turbine bypass control logic was developed based on the turbine bypass control system manual. The developed tool was merged into the simulator development environment. The functionality of the developed tool was verified via the simulation based on the each function block specification. The HP turbine bypass pressure control logic was implemented using the developed tool and was integrated with process models and other control models such as boiler control model, turbine control model and boiler feed water pump turbine control model for 500 MW korean standard type fossil power plant. Finally, the validity of the developed control model was shown via simulation result under the integrated simulation environment.

• Journal of information and communication convergence engineering
• /
• v.8 no.6
• /
• pp.665-670
• /
• 2010

This paper suggests the vehicle remote control on the basis of Smart Phone. In general, most smart phone is mounted with G-sensor to control the motion. G-sensor is able to control several directions and movements of velocity along with X, Y, and Z axis. To access remote location and data system, we can also utilize Wi-Fi communication as well as bluetooth communication. In this study, we propose the scheme that is the car management application by remote control via real-time monitoring on mobile device for user convenience.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.82.3-82
• /
• 2001

This work presents a design technique for the implementation of the liquid level control system by based on the use of a single-chip microcontroller. The proposed model system offers the following attractive features : (1) application of the pressure transducer for sensing the height of liquid in tank (2) using the obtained liquid level for defining on-off condition of the water pump (3) the liquid values were controlled by using stepping motors for controlling of 57 points (4) can set up by using manual control or automatic control (5) can monitor and display the process status either on microcontroller-based control board or on the computer via RS232 serial-port. Experimental results have been employed to show the effectiveness ...

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2004.10a
• /
• pp.63-66
• /
• 2004

The SGA(stochastic gradient ascent) algorithm is one of the most important tools in the area of reinforcement learning, and has been applied to a wide range of practical problems. In particular, this learning method was successfully applied by Kimura et a1. [1] to the control of a simple creeping robot which has finite number of control input choices. In this paper, we considered the application of the SGA algorithm to Kimura's robot control problem for the case that the control input is not confined to a finite set but can be chosen from a infinite subset of the real numbers. We also developed a MATLAB-based robot animation program, which showed the effectiveness of the training algorithms vividly.

• Journal of Mechanical Science and Technology
• /
• v.19 no.9
• /
• pp.1742-1752
• /
• 2005

This paper presents a Multiple Target Tracking (MTT) Adaptive Cruise Control (ACC) system which consists of three parts; a multi-model-based multi-target state estimator, a primary vehicular target determination algorithm, and a single-target adaptive cruise control algorithm. Three motion models, which are validated using simulated and experimental data, are adopted to distinguish large lateral motions from longitudinally excited motions. The improvement in the state estimation performance when using three models is verified in target tracking simulations. However, the performance and safety benefits of a multi-model-based MTT-ACC system is investigated via simulations using real driving radar sensor data. The MTT-ACC system is tested under lane changing situations to examine how much the system performance is improved when multiple models are incorporated. Simulation results show system response that is more realistic and reflective of actual human driving behavior.

• 제어로봇시스템학회:학술대회논문집
• /
• 1990.10b
• /
• pp.1355-1360
• /
• 1990

This paper describes the application of the recently developed feedback linearization technique to the design of a new command to line-of-sight (CLOS) guidance law for skid-to-turn (STT) missiles. The key idea lies in converting the three dimensional CLOS guidance problem to the tracking problem of a time-varying nonlinear system. Then, using a feeedback linearizing approach to tracking in nonlinear systems, we design a three dimensional CLOS guidance law that can ensure zero miss distance for a randomly maneuvering target. Our result may shed new light on the role of the feedforward acceleration terms used in the earlier CLOS guidance laws. Furthermore, we show that the new CLOS guidance law can be computationally simplified without performance degradation. This is made possible by dropping out the terms in the new CLOS guidance law, which obey the well-known matching condition.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.45-45
• /
• 2000

This paper proposes a remote control system that combines computer network and an autonomous mobile robot. We control remotely an autonomous mobile robot with vision via the internet to guide it under unknown environments in the real time. The main feature of this system is that local operators need a World Wide Web browser and a computer connected to the internet communication network and so they can command the robot in a remote location through our Home Page. The hardware architecture of this system consists of an autonomous mobile robot, workstation, and local computers. The software architecture of this system includes the server part for communication between user and robot and the client part for the user interface and a robot control system. The server and client parts are developed using Java language which is suitable to internet application and supports multi-platform. Furthermore, this system offers an image compression method using motion JPEG concept which reduces large time delay that occurs in network during image transmission.

• International Journal of Control, Automation, and Systems
• /
• v.6 no.2
• /
• pp.149-159
• /
• 2008

This paper considers the problem of adaptive fault-tolerant guaranteed cost controller design via dynamic output feedback for a class of linear time-delay systems against actuator faults. A new variable gain controller is established, whose gains are tuned by the designed adaptive laws. More relaxed sufficient conditions are derived in terms of linear matrix inequalities (LMIs), compared with the corresponding fault-tolerant controller with fixed gains. A real application example about river pollution process is presented to show the effectiveness of the proposed method.

• Journal of Power Electronics
• /
• v.16 no.3
• /
• pp.994-1003
• /
• 2016

Two major obstacles in the utilization of electrical vehicles are their price and range. The collaboration of direct torque control (DTC) with induction motor (IM) is preferred for its low cost, easy implementation, and parameter independency. However, in terms of edges, the method has drawbacks, such as variable switching frequency and undesired current harmonic distortion. These drawbacks result in acoustic noise, reduced efficiency, and electromagnetic interference. A feed-forward approach for stator-flux-oriented DTC with space vector pulse-width modulation is presented in in this paper. The outcome of the proposed method is low current harmonic distortion with fixed switching frequency while preserving the torque performance and simple application feature of basic DTC. The method is applicable to existing and forthcoming IM drive systems via software adaptation. The validity of the proposed method is confirmed by simulation and experimental results.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.8 no.7
• /
• pp.2512-2531
• /
• 2014

We propose a new Distributed Denial of Service (DDoS) defense mechanism that protects http web servers from application-level DDoS attacks based on the two methodologies: whitelist-based admission control and busy period-based attack flow detection. The attack flow detection mechanism detects attach flows based on the symptom or stress at the server, since it is getting more difficult to identify bad flows only based on the incoming traffic patterns. The stress is measured by the time interval during which a given client makes the server busy, referred to as a client-induced server busy period (CSBP). We also need to protect the servers from a sudden surge of attack flows even before the malicious flows are identified by the attack flow detection mechanism. Thus, we use whitelist-based admission control mechanism additionally to control the load on the servers. We evaluate the performance of the proposed scheme via simulation and experiment. The simulation results show that our defense system can mitigate DDoS attacks effectively even under a large number of attack flows, on the order of thousands, and the experiment results show that our defense system deployed on a linux machine is sufficiently lightweight to handle packets arriving at a rate close to the link rate.