• Korean Institute of Interior Design Journal
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• v.24 no.5
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• pp.99-107
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• 2015

The purpose of this study is to analyze the change of visual stimulus of users to the space through the experiment of EEG and the satisfaction of users depends on the lighting. To do that, the results measured with EEG experiment focusing on Beta ${\beta}$ were compared to each other to figure out difference in the changes of the activation of human brain on lighting's situation as the lighting off and on in the same space. The difference in the results was verified according to the characteristic of users which classified with 4 types of the spatial sensitivities. The results of this study are as following. Firstly, the spacial sensitivity of user is to communicate well with the different senses with stimulus through interaction among the elements. At this time, the brain plays a major role in build the spacial sensitivity of users as the place to make form. Secondly, there are the differences in the activation of brain depends on lighting situation even in the same space. The stimulus into the brain became generally stronger in images with lighting on than off. Especially, the response in the occipital lobe which connected with the visual center turn out strongly in the image of 'modern natural'. Because the visual stimulus interact well with the bright color, the reflectional texture and the rough texture painted the dark color. Thirdly, the satisfaction of users changed with lighting in the space. But we could know that the satisfaction of users isn't be related to the visual stimulus through the results of this study. Finally, there isn't the difference in the activation degree of brain according to the characteristic which are preference of users into 4 types of the spatial sensitivity through the results came from ANCOVA(analysis of covariance) with SPSS Program 22.

• Journal of Convergence for Information Technology
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• v.10 no.7
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• pp.138-146
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• 2020

The paper deals with comparative study of characteristics of surrogate models and sensitivity evaluation using design of experiments in order to enhance and analysis the structure design of an automatic salt collector under various design load conditions. Orthogonal array design based on numerical analysis was used for the design of experiments. The thickness sizing variables of main structure member were considered the design factors, and the output responses were selected from the strength performances as well as the weight. The quantitative effects on responses for each design factor were evaluated from the orthogonal array experiment. Optimum design case was also identified to improve the strength performances with weight minimization. Using the orthogonal array experiment. various surrogate models such as response surface model, Kriging model, and Chebyshev orthogonal polynomial were generated. The orthogonal array experiment results were validated by the surrogate modeling results. The most suitable surrogate model was the response surface model for the exploration of design space of the automatic salt collector.

• The Journal of Korea Robotics Society
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• v.8 no.1
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• pp.29-36
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• 2013

This paper presents a sensitivity optimization of a MEMS (microelectromechanical systems) gyroscope for a magnet-gyro system. The magnet-gyro system, which is a guidance system for a AGV (automatic or automated guided vehicle), uses a magnet positioning system and a yaw gyroscope. The magnet positioning system measures magnetism of a cylindrical magnet embedded on the floor, and AGV is guided by the motion direction angle calculated with the measured magnetism. If the magnet positioning system does not measure the magnetism, the AGV is guided by using angular velocity measured with the gyroscope. The gyroscope used for the magnet-gyro system is usually MEMS type. Because the MEMS gyroscope is made from the process technology in semiconductor device fabrication, it has small size, low-power and low price. However, the MEMS gyroscope has drift phenomenon caused by noise and calculation error. Precision ADC (analog to digital converter) and accurate sensitivity are needed to minimize the drift phenomenon. Therefore, this paper proposes the method of the sensitivity optimization of the MEMS gyroscope using DEAS (dynamic encoding algorithm for searches). For experiment, we used the AGV mounted with a laser navigation system which is able to measure accurate position of the AGV and compared result by the sensitivity value calculated by the proposed method with result by the sensitivity in specification of the MEMS gyroscope. In experimental results, we verified that the sensitivity value through the proposed method can calculate more accurate motion direction angle of the AGV.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.580-585
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• 2001

A response surface method(RSM) is utilized for structural optimization and implemented on a parametric CAD platform. Once an approximation of the performance function is made, no formal design sensitivity analysis is necessary. The approximation gives the designer the sensitivity information and furthermore intuition on the performance functions. The scheme for the design of experiment chosen for the RSM has a large influence on the accuracy of converged solutions and the amount of computation. The D-optimal design criterion as implemented in this paper is found efficient for the structural optimization. The program is developed on a parametric CAD platform and tested using several shape design problems of such as a torque arm and a belt clip. It is observed that the RSM used provides a faster convergence than other approximation methods for design sensitivity.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.3-8
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• 2004

When most manufacturing company produce grinding product operators decide grinding condition by experience and subjective judgment. The study on grinding manufacture have been developed to get the grinding condition with the same result when non-experienced or experienced worker work. The objective of this study is to develope the grinding condition and predict the result of grinding by neural network. Several discussions were made in following areas as; getting MRR with image processing, the architecture optimization of neural network with experiment design, analysis of the input neurons using sensitivity approach. The results showed that the developed approach was the best method in predicting grinding condition with respect to surface finish quality.

• Fire Science and Engineering
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• v.9 no.1
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• pp.20-29
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• 1995

The sprinkler head is a component of the sprinkler system intended to discharge water for automatic detection and extinguishment of fires. On this study, thermal characteristic values affecting the sensitivity of the fusible alloy type sprinkler head were obtained and analyzed under heated air stream condition which had constant temperature and velocity. The experiment was carried out under the forced convection condition with both the conductive heat loss considered and neglected. The thermal characteristic values of the sprinkler head were obtained in accordance with the material and shape of the heat responsive element and the conditions of the main body.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.773-782
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• 1998

The adsorption experiment of phenol(Ph) from aqueous solution on granular activated carbon was studied in order to design the fixed-bed adsorption column. The experimental data were analyzed by unsteady-state, one-dimensional heterogeneous model. Finite element method(FEM) was applied to analyze the sensitivity of parameter and to predict the fixed-bed adsorption column performance on operation variable changes. The prediction model showed similar effect to mass transfer and intraparticle diffusion coefficient changes suggesting that both parameter present mass transfer rate limits for GAC-phenol system. The Freundlich constants had a greater effect than kinetic parameters for the performance of fixed-bed adsorption column. FEM solution facilitated prediction of concentration history in solution and within adsorbent particle.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.7
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• pp.963-968
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• 2013

Ionizing Radiation effects on MOS devices provide useful information regarding the behavior of MOS based devices and circuits in the electronic instrumentation parts and instructive data for making the high sensitive sensors. The study presents the results of the analysis on the structural characteristics of MOS capacitor for sensing the ionizing radiation effect. We performed numerical modeling of Ionizing-radiation effect on MOS capacitor and simulation using Matlab program. Also we produced MOS capacitors and obtained useful data through radiation experiment to analyse the characteristic of ionizing radiation effect on MOS capacitor. Increasing the thickness of MOS capacitor's oxide layer enhanced the sensitivity of MOS capacitor under irradiation condition, but the sensitivity of irradiated MOS capacitor is uninfluenced by the area of MOS capacitor. The high frequency capacitance of the MOS capacitor is found to be strongly affected by incident ionizing radiation.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.9
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• pp.676-680
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• 1999

To do breath alcohol measurement, a sensor is necessary that it can detect low alcohol gas concentration of 0.01% at least. In this work, a capacitance-type alcohol gas sensor using porous silicon layer is developed to measure low alcohol gas concentration. The sensor using porous silicon layer has some sensitivity at room temperature by very large effective surface area, but there is still much room for improvement. In this experiment, we measured the capacitance of the sensor under 254 nm UV light on the porous silicon layer, in which alcohol solution was kept in a flask at 25, 35, and $45^{\circ}C$ by a heater. As the result, the improvement of sensitivity by illuminating UV light was observed. The increasing rate of the capacitance was shown to be double more than those measured under UV-off state. It is supposed that UV light activates response of the oriental and interfacial polarizations which have slow relaxation time for AC field.

• Transactions of The Korea Fluid Power Systems Society
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• v.6 no.1
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• pp.17-24
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• 2009

The performance improvement of a small-size integrated-type fully hydraulic breaker is studied in this paper. Mathematical modeling of the breaker is established and verified by experiment. Through sensitivity analysis using AMESim, the key design parameters are selected and nearly optimized to maximize the impact energy as well as to improve the dynamic characteristics such as the piston upper chamber pressure, piston and valve displacements. As a result, the impact energy, blows per minute(bpm) and output power are increased by 52.9%, 1%, and 55.6%, respectively compared with the current design. The dynamic characteristics of the piston upper chamber pressure, piston and valve displacements are also improved by the design change.