• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.148-150
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• 2001

Solid-phase microextraction (SPME) was investigated to understand the BTEX extraction behavior of SPME in groundwater. Analytical procedure was conducted In both conventional and headspace mode. And the conventional direct extraction method and the headspace analysis method were compared. Data obtained with direct and headspace SPME were very similar and showed successful results. In headspace analysis, the linearity was better and RSD (relative standard deviation, %) was smaller than direct extraction.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.681-684
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• 2007

This paper proposed and designed I-PD Controller using Shunji Manabe's CDM. The designed controller is applied to a level control system. The designed I-PD controller is smaller steady state error and get a specific response. A simulation results, the designed controller was better than a Fuzzy I-PD controller on a level control system.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1566-1569
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• 1997

In this paper, we developed newer cooling system which has better efficiency and make smaller pollution than older cooling system compressor type by using TEC Module. And then we investigated application of Peltier Effect cooling technology applied to the cold water dispenser.

• Journal of information and communication convergence engineering
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• v.6 no.3
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• pp.285-288
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• 2008

Most of multimedia processors for 2D/3D graphics acceleration use a lot of integer/floating point arithmetic units. We present a new architecture with an efficient ALU, built in a smaller chip size. It reduces instruction cycles significantly based on a foundation of multi-thread operation, variable length instruction words, dual phase operation, and phase instruction's coordination. We can decrease the number of instruction cycles up to 50%, and can achieve twice better performance.

• International journal of advanced smart convergence
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• v.4 no.2
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• pp.177-185
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• 2015

In this paper we introduce Kernel Fisher Discriminant Analysis (KFDA) to transform our database of received signal strength (RSS) measurements into a smaller dimension space to maximize the difference between reference points (RP) as possible. By KFDA, we can efficiently utilize RSS data than other method so that we can achieve a better performance.

• YAKHAK HOEJI
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• v.29 no.6
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• pp.380-386
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• 1985

The adsorption of quinine, atropine and methylrozaniline chloride from aqueous phase by different kaolins was studied to innovated utilization of Korean kaolins as pharmaceutical agents. The adsorption isotherms were determined at $27{\pm}1^{\circ}C$ and the results were plotted according to the Langmuir equation. The Langmuir constants were calculated from adsorption isotherms of quinine and methylrozaniline chloride; a=1.46, 1.34 b=5.7, 9.3 and slope=0.175, 0.108, respectively. The kaolins gave the same type of curves with the two alkaloids and methylrozaniline chloride. The white colored premium grade kaolins were better adsorbent for the alkaloids and methylrozaniline chloride than the lower grade ones. The results indicate that the premium grade kaolins could be utilized as an ingredients in intestinal preparations. The condition of activation for the better adsorption was under the cases with the higher temperature and the lower pressure. The smaller particle size, the greater was adsorption power and the activated kaolins had superior adsorptive properties at higher pH value than at higher hydrogen-concentrations.

• Journal of the korean Society of Automotive Engineers
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• v.10 no.6
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• pp.25-38
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• 1988

As a mean of increasing engine power, great attention has been concentrated on the turbo-charging owing to better fuel economy, smaller engine size and lower emission. The performance in turbocharged engine depends not only on the efficiency of the engine and the turbocharger used, but also on the total characteristics of the system by the matching turbocharger to the engine. The matching of the turbocharger to the engine has been usually accomplished by the empirical techniques with a great deal of laborious work. It would be better to predict the performance and emission in the turbocharged engine using the effective simulation model. In this study, computer simulation program has been developed to predict the transient variation of properties of gas in the cylinder, intake and exhaust pipes, the engine performances and emissions.

• Proceedings of the KWS Conference
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• 2003.05a
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• pp.260-262
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• 2003

In this study, high temperature tensile properties of high tensile strength steels(POSTEN60, POSTEN80) were investigated by elevated temperature tensile test. According toe the results, high temperature tensile strength of POSTEN60 deteriorated slowly to 100$^{\circ}C$. As the temperature went up the tensile strength became better because of blue shortness and it deteriorated radically after reached to the maximum value around 300$^{\circ}C$. For the POSTEN80, high temperature tensile strength deteriorated slowly to 200$^{\circ}C$.As the temperature went up the tensile strength became better and it deteriorated slowly to 600$^{\circ}C$ after reached to the maximum value around 300$^{\circ}C$. Strain of high tensile strength steels at the elevated temperature increased radically after the mercury rose to 600$^{\circ}C$. The strain hardening ratio of POSTEN60 was larger then that of POSTEN80 at the elevated temperature as in the case at the room temperature and it became smaller radically after the mercury rose to 400$^{\circ}C$.

• Journal of Advanced Marine Engineering and Technology
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• v.10 no.1
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• pp.51-64
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• 1986

Recently, being due to development of a small microprocessor, microprocessor have found increasing application as a digital controller in the control system. In this paper, authors analyze theoretically the continuous PID controller of a position control system with servomotor, and program the microprocessor as digital PID controller by an assembly language, and search the optimal parameters of the digital PID controller which make the smallest integral square error criterion for a performance criterion, and take experiment the indicial responses with optimal parameter. The results are following. 1) PD- behavior controller was better than P-behavior controller. 2) The smaller the smapling times of P-behavior controller and PD-behavior controller were, the better the indicial responses of the discrete system were. 3) Using a small microprocessor could replace the traditional continuous PID controller for good control.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.223-228
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• 2015

In this paper, the study of the optimum design for a geometry of the handle bar to obtain a high stiffness and light weight is investigated, using EDISON simulation program. High stiffness and weight lightening are considered as the major performance indicators of the component of the bicycle. Four design factors and three levels of the design factors are selected for the structural optimization and experiments are designed using the orthogonal array of L9 by Taguchi method. We calculated SN ratio of larger-the-better and smaller-the-better characteristics from FEA results and analysed the effects of design factors on characteristics. We choosed the optimum level of design factors based on deflection and safety factor. Comparing the results of FE analysis with converted value of predicted SN ration, we made sure for reliability of Taguchi method and FE method for structural optimization.