• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1994.10a
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• pp.49-58
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• 1994

The methods of estimation of VTS effectivenss are compared and the worldwide literature related to the VTS effectiveness is reviewed. The review suggests three potential approaches ; simulation ; synthesis of expert opinion and statistical analysis of casualties. this study adopted dissimilar approaches to estimate the VTS effectiveness to the earlier studies ; the combination of synthesis of expert opinion and causal analysis of casualty. The VTS effectiveness is derived by multiplying casualty rate reduction factors by the effect level of causal factors. The development of casualty rate reduction factors was based on the questionnaire survey and the evolution of effect levels was based on the causal analysis using functional block diagram. According to these procedures the maximum benefit to be obtained through the introduction of a VTS system was approximately 46 percent overall. The collision reduction rate was estimated to be approximately 50 percent for a VTS system with advanced radar surveillance. And 47 percent of groundings 36 percent of rammings and 21 percent of founderings could be reduced by the introduction of VTS. These figures are more or less the same to the earlier studies. The VTS effectiveness by the different causal factor groups was examined. VTS may reduce about 68 percent of causal factors classified as environmental conditions 40 percent of human factors and 35 percent of technical factors in collision accidents. As a whole 60 percent of environmental factors 41 percent of human factors and 20 percent of technical factors may be prevented by a VTS. The key variable of the effectiveness percentage is the value of weight coefficient $\delta$. Therefore differing values for this input was discussed and the impact that these variations have on the VS effectiveness noted. As the results of sensitivity analysis of VTS effectiveness by $\pm$10 percent the effectiveness is varied approximately three to seven percent by casualty type. And the value is changed roughly four to eight percent by a $\pm$10 percent variation by different sub-areas.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.571-573
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• 1996

A robust control technique of the PM synchronous motor is presented using an accelerating torque feedback. The accelerating torque is estimated by using an adaptive torque observer and then this estimated torque is controlled by a VSC technique. By employing the proposed torque control, the speed control performance of the motor is improved and the load independency can be realized. The simulations carried out for the PM synchronous motor to verily the effectiveness of the proposed control.

• Proceedings of the KIPE Conference
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• 1996.06a
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• pp.13-16
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• 1996

A new instantaneous torque control technique is presented for a high performance control of a permanent magnet synchronous motor. Using the model reference adaptive system technique, the linkage flux of the motor is estimated and the torque is instantaneously controlled by the proposed torque controller combining with a variable structure control and space vector PWM. The proposed torque control provides the advantage of reducing the torque pulsation caused by the flux harmonics. This control strategy is applied to the high torque PM synchronous motor drives for direct drive systems and is implemented by using a software of the DSP TMS320C30. The experiments are carried out for this system and the results well demonstrate the effectiveness of the proposed control.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1949-1954
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• 2005

One of control methods for underactuated manipulators is known as a switching control which selects a partially-stable controller using a prespecified switching rule. A switching computed torque control with a fuzzy energy region method was proposed. In this approach, some partly stable controllers are designed by the computed torque method, and a switching rule is based on fuzzy energy regions. Design parameters related to boundary curves of fuzzy energy regions are optimized offline by a genetic algorithm (GA). In this paper, we discuss on parameters obtained by GA. The effectiveness of the switching fuzzy energy method is demonstrated with some simulations.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.3
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• pp.298-312
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• 2014

This paper describes control applications in automobiles. Many aspects of automotive applications of advanced control methods, which include suspension systems, stability control systems, engines, hybrid vehicle control systems, electric vehicle controls systems, advanced driver assistance systems and automated driving control systems, are reviewed. The control methods used in each area are briefly reviewed to help readers understand the applicability and effectiveness of these methods. In addition, some new trends in the research of automotive applications are described.

• Transactions on Control, Automation and Systems Engineering
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• v.4 no.4
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• pp.347-355
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• 2002

Obstacle avoidance of underactuated robot manipulators using switching computed torque method (SCTM) is presented. One fundamental feature of this novel method is to use partly stable controllers (PSCs) in order to fulfill the ultimate control objective. Here, we use genetic algorithms (GAs) to acquire the optimum switching sequence of the control actions for a given time frame with the available set of elemental controllers, depending on which links/variables are controlled. The effectiveness of the concept is illustrated by taking a three-degrees-of-freedom (DOF) manipulator and showing enhanced performance of the proposed control methodology.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.566-571
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• 2009

A calibration method for multiple sets of stereo vision cameras is proposed. To measure the three-dimensional shape of a very long object, measuring the object at different viewpoints and registration of the data are necessary. In this study, two lasers beams generate two strings of calibration targets, which form straight lines in the world coordinate system. An evaluation function is defined to calculate the sum of the squares of the distances between each transformed target and the fitted line representing the laser beam to each target, and the distances between points appearing in the data sets of two adjacent viewpoints. The calculation process for the approximation method based on data linearity is presented. The experimental results show the effectiveness of the method.

• Journal of Electrical Engineering and information Science
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• v.2 no.3
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• pp.113-122
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• 1997

An adaptive input-output linearization technique for a robust speed control of a brushless C(BLDC) motor is presented. By using this technique, the nonlinear moro model can be effectively linearized in Brunovski canonical form, an the desired speed dynamics can be obtained based on the linearized model. This control technique, however, gives an undesirable output performance under the mismatch of the system parameters and load conditions caused by the incomplete linearization. for the robust output response, the controller parameters will be estimated by a model reference adaptive technique where the disturbance torque and flux linkage are estimated. The adaptation laws are derived by the Popov's hyperstability theory nd positivity concept. The proposed control scheme is implemented on a BLDC motor using the software of DSP TMS320C30 and the effectiveness is verified through the comparative simualtions and experiments.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.270-272
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• 1994

A new current control technique for inverter-fed vector controlled induction motor drives is presented. Using a integral variable structure control(IVSC) approach, the current controller is designed in the stationary rotating reference frame. The chattering reduction technique is also considered by the full state flux observer. By employing the proposed control scheme, a good control performance is achieved in the transient and steady state. The effectiveness of the proposed scheme is demonstrated through the comparative simulations.

• Structural Engineering and Mechanics
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• v.15 no.1
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• pp.135-149
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• 2003

The bubble packing method is implemented for adaptive mesh generation in two and three dimensions. Bubbles on the boundary of a three-dimensional domain are controlled independently of the interior bubbles in the domain, and a modified octree technique is employed to place initial bubbles in the three-dimensional zone. Numerical comparisons are made with other mesh generation techniques to demonstrate the effectiveness of the present bubble packing scheme for two- and three-dimensional domains. It is shown that this bubble packing method provides a high quality of mesh and affordable control of mesh density as well.