• 한국정밀공학회지
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• 제17권3호
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• pp.33-38
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• 2000

In process of tube spinning far shock absorber on vehicles, the selection of feed rate and rounding radius of forming roller and revolution speed of tube and forming roller, forming gap between die and forming roller are very important factors to obtain the optimal process result. In this paper, rigid-plastic FEM and UBET analysis are applied to verify effect of each factors by forming load. We can obtain the optimal conditions to prevent defects during processing.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.567-570
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• 2007

Cell gap dependence on anisotropic phase separation was studied. The results showed that the morphology of phase separation depended on cell gap and material parameters. With numerical simulation and experiments, the optimal range of cell gap in the formation of polymer layer and liquid crystal was suggested for given material parameters.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권11호
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• pp.541-546
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• 2006

In a levitation magnet system with large air gap, numerical method is needed because analytic method cannot consider the leakage flux properly. This paper conducted an optimal design of a levitation magnet system with large air gap which was used for an OLED system, where evolution strategy was adopted for optimal design algorithm. Levitation forces near the initial design were calculated first by using finite element method to reduce the computation time. During the optimization process, levitation forces of arbitrary dimension were obtained using the interpolation of the levitation forces which were calculated previously Weight of the maget system was chosen as the object function and it was used minimized.

• Journal of Audiology & Otology
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• 제24권3호
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• pp.149-156
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• 2020

Background and Objectives: The gap prepulse inhibition of the acoustic startle response has been used to screen tinnitus in an animal model. Here, we examined changes in the auditory late response under various conditions of gap prepulse inhibition. Subjects and Methods: We recruited 19 healthy adults (5 males, 14 females) and their auditory late responses were recorded after various stimuli with or without gap prepulsing. The N1 and P2 responses were selected for analysis. The gap prepulse inhibition was estimated to determine the optimal auditory late response in the gap prepulse paradigm. Results: We found that the gap per se generated a response that was very similar to the response elicited by sound stimuli. This critically affected the gap associated with the maximal inhibition of the stimulus response. Among the various gap-stimulus intervals (GSIs) between the gap and principal stimulus, the GSI of 150 ms maximally inhibited the response. However, after zero padding was used to minimize artifacts after a P2 response to a gap stimulus, the differences among the GSIs disappeared. Conclusions: Overall, the data suggest that both the prepulse inhibition and the gap per se should be considered when using the gap prepulse paradigm to assess tinnitus in humans.

• 대한청각학회지
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• 제24권3호
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• pp.149-156
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• 2020

Background and Objectives: The gap prepulse inhibition of the acoustic startle response has been used to screen tinnitus in an animal model. Here, we examined changes in the auditory late response under various conditions of gap prepulse inhibition. Subjects and Methods: We recruited 19 healthy adults (5 males, 14 females) and their auditory late responses were recorded after various stimuli with or without gap prepulsing. The N1 and P2 responses were selected for analysis. The gap prepulse inhibition was estimated to determine the optimal auditory late response in the gap prepulse paradigm. Results: We found that the gap per se generated a response that was very similar to the response elicited by sound stimuli. This critically affected the gap associated with the maximal inhibition of the stimulus response. Among the various gap-stimulus intervals (GSIs) between the gap and principal stimulus, the GSI of 150 ms maximally inhibited the response. However, after zero padding was used to minimize artifacts after a P2 response to a gap stimulus, the differences among the GSIs disappeared. Conclusions: Overall, the data suggest that both the prepulse inhibition and the gap per se should be considered when using the gap prepulse paradigm to assess tinnitus in humans.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(3)
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• pp.157-160
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• 2001

This paper has been studied a Adaptive Mutation rate Genetic Algorithm Processor. Genetic Algorithm(GA) has some control parameters such as the probability of bit mutation or the probability of crossover. These value give a priori by the designer There exists a wide variety of values for for control parameters and it is difficult to find the best choice of these values in order to optimize the behavior of a particular GA. We proposed a Adaptive mutation rate GA within a steady-state genetic algorithm in order to provide a self-adapting mutation mechanism. In this paper, the proposed a adaptive mutation rate GAP is implemented on the FPGA board with a APEX EP20K600EBC652-3 devices. The proposed a adaptive mutation rate GAP increased the speed of finding optimal solution by about 10%, and increased probability of finding the optimal solution more than the conventional GAP

• East Asian Economic Review
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• 제22권3호
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• pp.337-370
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• 2018

This paper discusses the design of monetary policy in a New Keynesian small open economy framework by introducing nominal wage rigidities and incomplete exchange rate pass-through on import prices. Three main findings are summarized. First, with the existence of an incomplete exchange rate pass-through and nominal wage rigidities, the optimal policy is to seek to minimize the output gap, the variance of domestic price and wage inflation, as well as deviations from the law of one price. Second, the CPI inflation targeting Taylor rule is welfare enhancing when there is a technological shock to the economy. The exception occurs when there is a foreign income shock, which minimizes welfare losses under the domestic inflation targeting Taylor rule. Last, two stylized Taylor rules turn out to be a bad approximation, but the modified Taylor rules that respond to the unemployment gap rather than the output gap are a closer approximation to the optimal policy.

• 한국정밀공학회지
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• 제20권8호
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• pp.76-85
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• 2003

In this paper, a technical method for removing the solder from PCBs has been proposed to simplify the pulverizing process and to get higher quality of materials for recycling of the electronic parts in the Printed Circuit Boards (PCBs). There are several techniques to remove the solder from PCB, such as physical and chemical method, vibration, suction and blowing and so on. Among them, the suction technique turned out the best method by investigation. In the suction method, there are three variables for removing the solder. They are a temperature of the thermal wire, a velocity of moving PCB and a gap between PCB and thermal wire. To find the optimal variables for the system, an experiment has been conducted by a trial and error method. The optimal variables were found $220^{\circ}C$ of temperature, 11.58mm/s of velocity, 10mm of gap (A gap between suction hole and bottom of PCBs is 5mm). The result of the experiment shows that 50% of the solder were removed.

• Journal of Power Electronics
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• 제12권2호
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• pp.305-316
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• 2012

The paper presents an accurate loss model based controller of an induction motor to calculate the optimal air gap flux. The model includes copper losses, iron losses, harmonic losses, friction and windage losses, and stray losses. These losses are represented as a function of the air gap flux. By using the calculated optimal air gap flux compared with rated flux for speed sensorless indirect vector controlled induction motor, an improvement in motor efficiency is achieved. The motor speed performance is improved using a fuzzy logic speed controller instead of a PI controller. The fuzzy logic speed controller was simulated using the fuzzy control interface block of MATLAB/SIMULINK program. The control algorithm is experimentally tested within a PC under RTAI-Linux. The simulation and experimental results show the improvement in motor efficiency and speed performance.

• 대한기계학회논문집A
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• 제30권8호
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• pp.1016-1023
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• 2006

When one opens the door of a microwave oven during its operation, twisting deformation of the door occurs, which may cause leakage of microwave through the gap between the door and the front plate. A numerical optimization is implemented to minimize the gap by maximizing twisting stiffness of the door of the oven. Design variables are deformed, which describe the shape of the bead in the horizontal and vertical flanges of the door frame. To minimize the twisting deformation, Two optimal design problems to find shapes of the bead in the flange are established. The problems are solved by a numerical optimization technique, their results being evaluated.