• International Journal of Control, Automation, and Systems
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• v.3 no.1
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• pp.15-31
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• 2005

Nowadays, the road safety is an important research field. One of the principal research topics in this field is the vehicle localization in the road network. This article presents an approach of multi sensor fusion able to locate a vehicle with a decimeter precision. The different informations used in this method come from the following sensors: a low cost GPS, a numeric camera, an odometer and a steer angle sensor. Taking into account a complete model of errors on GPS data (bias on position and nonwhite errors) as well as the data provided by an original approach coupling a vision algorithm with a precise numerical map allow us to get this precision.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1995.10b
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• pp.145-152
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• 1995

This paper presents a novel SOFLIC(self organizing fuzzy logic intelligent controller) for reactor rod control system in nuclear power plant. The output of fuzzy controller is gener ated by using two signal : the error between reference and average temperature, and the error between reference and neutron flux-converted temperatures. Flexibility of the controller is enhanced by using self-organizing feature and the controller respond to variation of system parameter with more precision. performances of the SOFLIC and PID are simulated with the model developed for a nuclear power plant. The SOFLIC is superior to PID : SOFLIC provides more rapid load following capability. more robustiness for variation in process dynamics and minimization of engineer's mistakes in controller design.

• Nuclear Engineering and Technology
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• v.50 no.6
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• pp.877-885
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• 2018

Various controllers such as proportional-integral-derivative (PID) controllers have been designed and optimized for load-following issues in nuclear reactors. To achieve high performance, gain tuning is of great importance in PID controllers. In this work, gains of a PID controller are optimized for power-level control of a typical pressurized water reactor using particle swarm optimization (PSO) algorithm. The point kinetic is used as a reactor power model. In PSO, the objective (cost) function defined by decision variables including overshoot, settling time, and stabilization time (stability condition) must be minimized (optimized). Stability condition is guaranteed by Lyapunov synthesis. The simulation results demonstrated good stability and high performance of the closed-loop PSO-PID controller to response power demand.

• Journal of Industrial Convergence
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• v.6 no.1
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• pp.17-33
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• 2008

The purpose of this study is to examine what sort of causes have the effect on the coping behavior of the unemployed against their job loss. For the purpose of the study, following independent variables have been selected, locus of control, self-efficacy and autotelic personality. As dependent variables, two types of coping behaviors of individual have been used, problem-focused coping strategies and symptom-focused coping strategies. To test the hypotheses, structural equation modeling was employed. The model showed adequate fit to the data. The results of structural equation modeling exhibit that internal locus of control, self-efficacy and autotelic personality were positively related problem-focused coping strategies. And self-efficacy was negatively related to symptom-focused coping strategies. Implications are discussed and future research directions are outlined.

• Journal of Wellness
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• v.6 no.3
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• pp.13-21
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• 2011

The purpose of this study was to examine the potential predictors of leisure behavior intention using the theory of planned behavior(TPB). A convenience sample of 369 participants was obtained from university students in Korea and America. For the purposes of this study, potential predictors of leisure behavior intention were selected from the following categories: attitude, subject norm, perceived behavior control, group conformity and face saving. In order to better understand the dynamics of the TPB process that influenced leisure behavior intention, this study used structural equation modeling(SEM) to test the TPB model. According to the results, attitude, subject norm, and perceived behavior control influenced to leisure behavior intention of both Korean and American university students and face saving influenced to leisure behavior intention of Korean university students. However, group conformity did not influence to leisure behavior intention of either Korean and American university students. For future study, more specific and decomposed factors are recommended to understand leisure behavior intention in theoretical way.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1883-1887
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• 1991

Identification theory for linear discrete system has been presented by a great many reference, but research works for identification of continuous-time system are less than preceding identification. In fact, a great man), systems for engineering are continuous-time systems, hence, research for identification of continuous-time system has important meaning. This paper offers the following results: 1. Corresponding relations for the parameters of continuous-time model and discrete model may be shown, when single input-output system has general characteristic roots. 2. To do identification of single variable continuity linear system with stability constraints from samples of input-output data, it is necessary to use optimization with stability constraints. 3. Main results of this paper may be explained by a simple example.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.11a
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• pp.125-128
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• 2005

This paper presents a simple methodolosy that makes a continuous-time nonlinear system chaotic using fuzzy control. The nonlinear system is represented by the T-S fuzzy model. Then, a fuzzy controller makes the T-S fuzzy model, which could be stable or unstable, bounded and chaotic. The verification of chaos in the closed-loop system is done by the following procedures. We establish an asymptotically approximate relationship between a continuous-time T-S fuzzy system with time-delay and a discrete-time T-S fuzzy system. Then, we verify the chaos in the closed-loop system by applying the Marotto theorem to its associated discrete-time T-S fuzzy system.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.365-368
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• 1996

The setting of the factory under this study is as the following. There are multiple assembly lines. Each line can handle any of given set of products. Furthermore each line is capable of assembling several products concurrently, i.e. mixed model assembly line. An incoming production order is characterized by its due-date, product type and quantity. Under this setting we first have to select the starting time and the place(assembly line) for an order to be processed. We also have to devise a way to control orders to be manufactured as scheduled. Finally there should be a mean to reschedule orders when something unexpected happens. This paper offers a scheme that provides the above mentioned necessities. It also provides a case where the scheme is applied.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.308-312
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• 1989

We developed a model of NC controller with IBM-PC as a host cpu and integlligent NC servo controller for 2 axes that can be expaned to 4 axes. Basic conceptions, including hardware structure design, servo controller design, communication protocol, and interpolation hardware design was already publicated on '87 KIEE conference. Following this, we focussed on the emulation of tyhe controller with X-Y table as complete NC machine experimenting some drawings made by NC code program that can be edited and executed in automatic on single step mode. In addition we designed the M.S.T functions with PLC and tested for M-function timing. Finally, we designed NC interface to fit with M-function output and we contructed total system of NC controller with IBM PC host with the result of successful development of new NC model.

• Journal of Korean Society on Water Environment
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• v.33 no.1
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• pp.8-14
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• 2017

Microcystis aeruginosa (M. aeruginosa) is a cyanobacterium species that can form harmful algal blooms in freshwater bodies worldwide. The use of pine needle extract (PNE) to control nuisance algae by allelopathic inhibition will be environmentally friendly and promising. PNE removed successfully upto 98% of M. aeruginosa at the following optimal conditions: pH 7, $25^{\circ}C$ of temperature, 100 rpm of mixing rate, 5 min of mixing time. These results was indicated that the amount of 1 g/L PNE was removed 1g dryweight/L of M. aeruginosa. The kinetic data showed substrate inhibition kinetics and maximum growth rate was obtained when the M. aeruginosa was grown in medium containing 0.5 g/L of initial concentration of PNE. Different substrate inhibition models were fitted to the kinetic data and found the Luong model was best. The model predicted kinetic parameters were in agreement with the experimental findings. The natural extract, PNE, can be a promising inhibition due to its high efficiency and low dose requirements.