• Communications of the Korean Mathematical Society
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• v.11 no.3
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• pp.695-706
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• 1996

In the control system $ \dot{x} = f(t,x(t)) + g(t,x(t))\dot{u}, x(0) = \bar{x}, t \in [0,T], $ this paper shows that the map from u with $L^1(m)$-topology to $x_u$ with $L^1(\mu)$-topology is Lipschitz continuous where f is $C^1$, $\mu$ is the Stieltjes measure derived from the function g which is not smooth in the variable t and $x_u$ is the solution of the above system corresponding to u under the assumption that $\dot{u}$ is bounded.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.47-51
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• 1993

A method of finding the optimal actuator location for efficient control of the modes of interest is presented. The proposed approach relies on certain quantitive measure of degree of controllability based on the controllability grammian. This measure proves to be useful for regulating problem of the undamped system and can be extended to cover the tracking problem of the viscous damped system. The example of the uniform cantilever beam is given to verify the effectiveness of the method.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.9
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• pp.891-897
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• 2010

This paper proposes a cooperative control algorithm for a dual-arms robot which is carrying an object to the desired location. When the dual-arms robot is carrying an object from the start to the goal point, the optimal path in terms of safety, energy, and time needs to be selected among the numerous possible paths. In order to quantify the carrying efficiency of dual-arms, DAMM (Dual Arm Manipulability Measure) has been defined and applied for the decision of the optimal path. The DAMM is defined as the intersection of the manipulability ellipsoids of the dual-arms, while the manipulability measure indicates a relationship between the joint velocity and the Cartesian velocity for each arm. The cost function for achieving the optimal path is defined as the summation of the distance to the goal and inverse of this DAMM, which aims to generate the efficient motion to the goal. It is confirmed that the optimal path planning keeps higher manipulability through the short distance path by using computer simulation. To show the effectiveness of this cooperative control algorithm experimentally, a 5-DOF dual-arm robot with distributed controllers for synchronization control has been developed and used for the experiments.

• Journal of Korean Institute of Industrial Engineers
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• v.23 no.4
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• pp.699-708
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• 1997

Production control is usually composed of due-dote assignment, production input control, and priority dispatching rule. A production input control(PIC) is mainly to control the WIP level on the shop floor. On the other hand, a priority dispatching rule(PDR) is mainly to control the tardiness/earliness of on order and number of tardy jobs. Therefore, if we select a particular PIC which can control only a particular performance measure(i.e., tardiness), it may cause worsening other performance measure(i.e., WIP level, shopfloor time, etc.) This newly developed production input control, DRD(Dual Release-Dates), is mainly designed to control the WIP level on the shop floor by employing two different release-dates of an order(earliest release. date and latest release-date and the release condition (relationship between the current WIP level and the pre-defined maximum WIP level) while trying to meet the due-date of the order.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.12
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• pp.2505-2510
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• 2009

Semiconductor processes need measurement to confirm where there are problems in quality after progresses manufacturing process. This paper suggests equipment and automatic measure sampling method that control monitoring ratio according to change point occurrence availability of process that is not measure method by the existent simple ratio rate. This paper defines measure section as ailment section, metastable section and stability section by change point standard and create statistical model of each section and developed suitable measure rate model by section. As a result, we have accomplished maximum throughput and minimum sampling number that needs to maintain constant level of quality. Proposed method minimizes load of measure process by brings production quality sophistication and decrease of process badness and lowers measure rate in stable section making perception about problem occurrence quick heightening measure rate at change point occurrence.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.5
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• pp.958-965
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• 2007

The spreaders on container cranes are usually controlled to stop at the same time as their trolleys are stopped. Despite the use of adequate control systems, however, the spreaders usually have comparatively large sway movements, due to their suspension from the trolleys through cables. It is, therefore, important to accurately measure the attitudes of the spreaders, in order to suppress such sways by means of secondary control. Until now, most of conventional anti sway control systems focus on the direct control of the movements of trolleys. which seems not suitable to speed up the entire process - loading and unloading of containers. In this paper, we suggest a new anti sway control system: By using extra equipments - two propellers to suppress the sway and a PSD camera to measure the spreader's attitude - installed on the spreader and the trolley. the sway of the suspended load j, considerably suppressed. The effectiveness of the proposed scheme is verified by the computer simulation and experiment with the miniature of the container crane system.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.12
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• pp.1152-1158
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• 2011

In this paper a configuration of the load evaluation device for the tilting actuator using hydraulic power is presented, which makes it possible to measure the force action on the tilting actuator. It is possible to measure only current using the conventional electro-mechanical actuator when the bogie is in the process of the tilting. This makes impossible to measure the force acting on the tilting actuator. In order to overcome this problem a kinetic mechanism test system using hydraulic cylinder is proposed. The system are consisted of hydraulic cylinder for the tilting actuation, control system to control hydraulic power, sensors to measure for force and displacement and monitoring system for the user interface.

• Journal of Korean Society for Quality Management
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• v.33 no.4
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• pp.96-102
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• 2005

Cusum control chart is an efficient method to detect the change of process status. Many variants of cusum have considered, and the effects of design parameters have reviewed. To find the best cusum out of variants and to decide the best values of the design parameters, we need a criterion measuring the performance of the cusum control chart. People used and suggested several criterions which appear to be similar, but those have quite different properties. In this paper we review the properties of performance measure of cusum and its variants. Our goal is to provide fair and impartial criterion for comparison of cusums when the decision boundaries of the cusums are much different each other. We comparatively tested newly suggested measure and traditional measure with the examples of cumulative scored chart as a special case of cusum chart.

• Journal of applied mathematics & informatics
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• v.9 no.2
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• pp.717-730
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• 2002

In this paper we use measure theory to solve a wide range of the nonlinear programming problems. First, we transform a nonlinear programming problem to a classical optimal control problem with no restriction on states and controls. The new problem is modified into one consisting of the minimization of a special linear functional over a set of Radon measures; then we obtain an optimal measure corresponding to functional problem which is then approximated by a finite combination of atomic measures and the problem converted approximately to a finite-dimensional linear programming. Then by the solution of the linear programming problem we obtain the approximate optimal control and then, by the solution of the latter problem we obtain an approximate solution for the original problem. Furthermore, we obtain the path from the initial point to the admissible solution.

• Journal of applied mathematics & informatics
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• v.14 no.1_2
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• pp.97-113
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• 2004

In this paper we shall study moving boundary problems, and we introduce an approach for solving a wide range of them by using calculus of variations and optimization. First, we transform the problem equivalently into an optimal control problem by defining an objective function and artificial control functions. By using measure theory, the new problem is modified into one consisting of the minimization of a linear functional over a set of Radon measures; then we obtain an optimal measure which is then approximated by a finite combination of atomic measures and the problem converted to an infinite-dimensional linear programming. We approximate the infinite linear programming to a finite-dimensional linear programming. Then by using the solution of the latter problem we obtain an approximate solution for moving boundary function on specific time. Furthermore, we show the path of moving boundary from initial state to final state.