This paper deals with the robust stability of discrete-time linear systems with time- varying delays and norm-bounded uncertainties. In this paper, the magnitude of time-varying delays is assumed to be upper-bounded. The sufficient condition is presented in terms of linear matrix inequality. It is also shown that the robust stability of uncertain discrete-time linear systems with time-varying delays is related with the quadratic stability of uncertain discrete-time linear systems with constant time delay.

For linear time-varying systems described by the triple (A(t),B(t),C(t)) where A(t),B(t),C(t) are the system, the input, and the output matrices, respectively, we propose concepts for measures of modal and gross controllability /observability. We introduce a differential algebraic eigenbvalue theory for linear time-varying systems to calculate the PD-eigenvalues and left and right PD-eigenvectors of the system matrix A(t) which will be used to derive the concepts for the measures. The time-dependent angle between the left PD-eigenvectors of the system matrix A(t) and the columns of the input matrix B(t), and the magnitude of the each element of the input matrix B(t) are used to propose the modal controllability measure. Similarly, the time-dependent angle between the right PD-eigenvectors of the system matrix A(t) and the rows of the output matrix C(t) are used to propose the madal observability measure. Gross measure of controllability of a mode from all inputs and its gross measure of observability in all outputs for the linear time-varying systems are also proposed. Numerical examples are presented to illustrate the proposed concepts.

In this paper, we design the optimal PD control system which has the robust performance. This PD control system is designed by applying genetic algorithm (GA) to the determination of proportional gain KP and derivative gain KD that are given by PD servo controller, to make the output of plant follow the output of reference model optimally. These proportional and derivatibe gains are simultaneously optimized in the search domain guaranteeing the robust performance of system. And, this PD control system is compared with $\mu$ -synthesis control system for the robust performance. The PD control system designed by the proposed method has not only the robust performance but also the better command tracking performance than that of the $\mu$ -synthesis control system. The effectiveness of this control system is verified by computer simulation.

In this paper, we propose a robust controller design of RTP(Rapid Thermal Processing) system using structured uncertainty approach. Using the weighted mixed sensitivity function, we solve the robust stability problem against disturbance and temperature variation, and design a $\mu$ controller using curve fitting method against structured uncertainty. Also the reduction method should be requried because of the difficulty of implementaion with the obtained high order controller. We dal with robust stability and performance of RTP system by the design of $\mu$ controller for original model and Schur balanced reduced model. Finally the simulation results are proposed to show the validity of the proposed method.

A study which develops a controller design methodology that has flexibility of eigenstructure assignment within the stability-robustness contraints of LQR is requried and has been performed. The previously developd control design methodology, namely, EALQR(Eigenstructure Assignment/LQR) has better performance than that of conventional LQR or eigenstructure assignment but has a constraint for the weitgting matrix in LQR, which could be indefinite for high-order system. In this paper, the effects of the indefinite Q in EALQR on the frequency domain properties are analyzed. The robustness criterion and quantitative frequency domain properties are also resented. Finally, the frequency domain properties of EALQR has been analyzed by applying to a flight control system design example.

This paper deals with a fault-tolerant control method for robust control of RPV(Remotely Piloted Vehicle). To design the flight control system, the 6-DOF simulation program has been developed based on the dynamic model of RPV. A robust fault detection and diagnosis method proposed by Kwon et al. [8]-[10] is adopted to detect the actuator fault of RPV and to make the controller reconfiguration. The Hoo control method is applied to the flight control system. An integrated simulation for performance evaluation of the fault-tolerat\nt control system designed is performed via 6 DOF simulation and shows that the control system works even under the actuator fault.

This paper describes the implementation of a high speed image processing board. This image processing board is consist of a image acquisition part and a image processing part. The image acquistion part is digitizing the image input data from CIS and save it to the dual port RAM. By putting on the dual port memory between two parts, during acquistion of image, the image processing part can be effectively processing of large-volume image data. Most of all image preprocessing part are integrated in a large-scaled FPGA. We arwe using ADSP-2181 of the Analog Device Inc., LTD. for a image processing part, and using the available all memory of DSP for the large-volume image data. Especially, using of IDMA exchanges the data with the external microprocessor or the external PC, and can watch the result of image processing and acquired image. Finally, we show that an implemented image processing board used for the simulation of image retreval by the one of the typical application.

There are several types of defects of SMDs mounted on PCB, that is, missing components, misalignment, wrong parts and poor solder joints. This research study mainly focuses on measuring of deviation of SMD leads using the partial image of component, not using the full image. This processing based on the partial image has the advantage of the reduction in calculation time compared to the full image. Since position of lead is calculated with respect of the reduction in calculation time compared to the full image. Since position of lead is calculated with respect to pad, the accuracy of the system is not dependent on percise positioning stage. The grabbed image of gray scale is converted into binary format using a cutomatic threshold. After small fragments in the image is removed by a series of morphology operations such as opening and closing, the centroids of PCB pads and SMD leads is obtained together with labeling of blobs. Translational shift and rotationial angle of SMD are succedingly estimated using above information and chip data. The expression that can calculate the maximum deviation of leads with respect to PCB pads has been derived, and inferior mounting of SMD is judged by a given criterion. Some experiments have been executed to verify this measuring scheme.

In this paper, we propose a new motion and force control methodology for constrained robots as an approach of hybrid discrete-continuous dynamical system. The hybrid dynamic system modeling of robotic manipulation tasks with constraints is presented, and the hybrid system control architecture for unconstrained and constrained motion system with parametric uncertainties is synthesized. The optimal reference stiffness of robot manipulator is generated by the hybrid automata as a discrete state system and the control behavior of constrained system which has poor modeling information and time-varying constraint function is improved by the constrained robots as a continuous state system. The performance of the proposed constrained motion control system is successfully evaluated via experimental studies to the constraint tasks.

This paper presents a short-term scheduling algorithm for the operation of steelmaking processes. The scope of the problem covers refining of the hot iron transferred form a blast furnace, ladle treatment, continuous casting, hot-rolling, and coiling for the final products that should satisfy the given demand. The processing time at each unit depends on how much the batch amount is treated, and te dedicated intermediate storage with finite capacity between the units is considered. Resource constraints and initial amount of each state are incorporated into the presented scheduling model for the algorithm of on-line scheduling. We propose amixed integer linear programming (MILP) model with two objectives for the scheduling. The first is to maximize the total profit while atisfying the due date constraint for each product. And the second is to minimize the total processing time, makespan, while satisfying the demand for each product. Especially, we observe the effect of penalizing the intermediate storage and the inventory level of the final product on the scheduling results.

An effective method of system modeling and dynamic scheduling for the back-end line of semiconductor manufacturing is proposed. The virtual factory, describing semiconductor manufacturing line, is designed in detail, and then a Petri net model simulator is developed for operation and control of the modular cells of the virtual factory. The petri net model is a colored timed Petri nets (CTPNs). The simulator will be utilized to analyze and evaluate various dynamic status and operatons of manufacturing environments. The dynamic schedulaer has a hierarchical structure with the higher for planning level and the lower for dynamic scheduling level. The genetic algorithm is applied to extract optimal conditions of the scheduling algorithm. The proposed dynamic scheduling is able to realize the semiconductor manufacturing environments for the diversity of products, the variety of orders by many customers, the flexibility of order change by changing market conditions, the complexity of manufacturing processes, and the uncertainty of manufacturing resources. The proposed method of dynamic scheduling is more effective and useful in dealing with such recent pressing requirements including on-time delivery, quick response, and flexibility.

In this paper, a real-time communication method using a PICNET-NP(Plant instrumentation and Control Network for Nuclear Power plant) is proposed with an analysis of the control network requirements of DCS(Distributed Control System) in nuclear power plants. The method satisfies deadline in case of worst data traffics by considering aperiodic and periodic real-time data and others. In addition, the method was used to analyze the data characteristics of the DCS in existing nuclear power plant. The result shows that use of this method meets the response time requirement(100ms).

In this paper, we studied the response characteristics of $\alpha$, $\beta$ separated type, combined type, PI typed, and feedforward type in 2DOF-PID controller through the simulation and the experiments designed with the multivariable flow control system. The parameters $\alpha$ and $\beta$ give an affect to characteristics of controller in separated type but $\gamma$ does not give an affect to the characteristics of 2-DOF PID. The more $\beta$ increases, the more overshoot decreases and especially, in case of PI type represent clearly. The $\alpha$, $\beta$ separated type has a very small overshoot and its magnitudes in 2-DOF PID onctroller increases in order of $\alpha$, $\beta$ combined type, PI type, feedforward type, conventional type. The response characteristics of simulation are similar to that of experiments but the experimental characteristics in the multivariable flow control system has the delayed response. The time delay of response in experiments depends on 2-DOF parameter $\alpha$, $\beta$, $\gamma$ and the overshoot increase as the $\alpha$, $\beta$, $\gamma$ increase. So, we can have a satisfactory response by tuning D gain.

The existing SCADA(Supervisory Control and Data Acquisition) system software is usually developed to suitable for the specific hardware platforms. However, as per rapid improvement of computer performance and development of network technology, it is required to support scalability and inter-operability in existing different SCADA systems. In order to meet such requirements, in this paper, we propose a new type of SCADA testbed using Java for electric distribution applications. The system consists of three modules; development support tools, client and server modules. The basic architecture of the proposed SCADA system is similar to existing one, however, we improve the function of MTU and MMI interface to facilitate LAN and WAN environment. Also, the proposed system can deals with alarm and history data by using heterogeneous DBMS. Since the system is built in Java environment, the development cost is cheap and it can support sacalability and portability. Our experience can be utilized to develop next generation of small and medium size of SCADA system.

In this paper, a tracking algorithm for a maneuvering single target in the presence of multiple data from multiple sensors is investigated. Allowing individual sensors to function by themselves, the estimates from individual sensors on the same target are fused for the purpose of improving the state estimate. The filtering method adopted in the local sensors is the variable dimensional filter with input estimatio technique, which consists of a constant velocity model and a constant acceleration model. A posteriori probability for the maneuvering hypothesis is newly derived. It is shown that the relation function of the a posteriori probability is a function of only the covariance of the fused estimates. Simulation results are provided.