• Proceedings of the Safety Management and Science Conference
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• 2012.04a
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• pp.75-80
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• 2012

The research presents a guideline for quality practitioners to provide a full comprehension of differences in theoretical and practical interpretations of assumed sampling errors of and significance probability of calculated p-value. Besides, the study recommends the use of statistical inferences methods with known parameters to identify the improvement effects. In practice, the quality practitioners obtain the known parameters through systematic quality Database (DB) activities.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.257-262
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• 2001

A numerical analysis is undertaken to show tile influence of bearing design parameters on tile load capacity of air lubricated spiral grooved thrust bearing. The governing equation derived from the mass balance is solved by the finite difference method. Optimal values for various design parameters are obtained to maximize the load capacity. The design parameters are the groove angle, the groove width ratio, the groove height ratio, arid the seal ratio.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.5
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• pp.310-314
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• 2000

To study the basic research of the lightning parameters for power system operation, LPATS(Lightning Positioning and Tracking System) has been introduced since 1995 in KEPCO(Korea Electric Power Corporation). We have developed the lightning parameters analysis program which can produce accumulative magnitude distribution of lightning current and IKL map by LPATS data. We obtained the various statistical distributions of lightning current parameters since 1996 by the lightning analysis program for the pertinent insulation design. In this paper, we describe the LPATS system in KEPCO, the statistical distribution of lightning current parameters and the IKL(Isokeraunic Level) map from 1996 to 1998. And the compared results between the calculated LFOR(lightning flashover rate) and the observed rate are also described.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.3-11
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• 2002

Source parameters for forty nine recent earthquakes occurred in and around Korean Peninsula are determined and the relations among them are studied. The corner frequency and seismic moment are estimated from three different methods. The spectral fitting of the source displacement spectrum with the $\omega$-square source model of Brune(1970) and Snoke(1987)'s method are applied to all events and empirical Green's function method for two events are adopted. The source parameters determined in this study show different values depending on the adopted method and on the stations of which seismograms are recorded. It is interpreted that the disagreements principally originate from insufficient consideration of source radiation pattern and attenuation and amplification according to path direction. The corner frequencies and seismic moments are averaged to exclude the directional effects and other source parameters are estimated from the mean corner frequency and seismic moment. The static stress drops estimated in this study tend to be independent of seismic moment or magnitude for events above a certain size. For earthquakes with the size less than about 3.0$\times$10$^{21}$dyne-cm(nearly same as M$_{L}$=3.7), the stress drop tends to decrease with the decreasing moment. This fact suggests a breakdown of scaling law of source parameters below the threshold magnitude. The moment magnitudes calculated from source parameters appear to be slightly larger than the Richter's local magnitudes in the range above M$_{L}$=3.5.3.5.

• Journal of Korean Foot and Ankle Society
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• v.11 no.1
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• pp.8-12
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• 2007

Purpose: The purpose of this study was to investigate the differences in simple radiographic parameters and results of 3-D scan among normal and patient groups. Materials and Methods: Seventy subjects in each group were studied. Control group consisted of subjects without plantar foot pain (normal group), and two patient groups were one with plantar forefoot pain (metatarsalgia group), the other with plantar heel pain (heel pain group). Simple radiographic parameters were obtained and 3-D scan was done with foot scanner (Nexscan, K&I, Korea) and The height and volumn of the space under the medial longitudinal arch was analyzed (Enfoot, K&I, Korea). These parameters were compared and correlation between radiological parameters and results of the 3-D scan were studied. Results: The results of all parameters istributed normally. There was no signigicant differences among the groups in radiological parameters (talo-first metatarsal angle, calcaneal pitch angle and height of the talar head in standing lateral radiograph) and arch height and arch volumn on 3-D scan. There were statistically significant correlations between radiological and 3-D scan results. Conclusion: This study revealed that there is no significant differences in medial longitudinal arch height and volumn among normal and different patient groups and there are variety of arch height in patients with similar symptoms.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.17 no.1
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• pp.17-27
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• 2006

Background and Objectives: Vocal polyp is the most common disease that causes hoarseness and its incidence is increased currently. The purposes of this study are to investigate the correlation between severity of vocal polyp and acoustic parameters and compare these data with those of the normal Korean. Materials and Methods: We analyzed the acoustic parameters of sustained vowel for 70 vocal polyp patients and 20 normal controls. A CSL(computerized speech lab) was used to carry out the analysis of the voice sample and statistical analysis was used Spearman correlation coefficient & t-test. Results: According to the conclusion of correlation analysis, 21 parameters of all the 34 parameters are significant. Conclusion: These data will be served as basic data for the evaluation of postoperative assessment of the patients with vocal polyp.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.3
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• pp.133-142
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• 2010

The present work focuses on the characterization of material parameters of the Overlay(multilinear hardening) model for analyzing the non-isothermal cyclic deformation. In the previous study, all the parameters were especially based on the Overlay theories, and a simple method was suggested to find out the best material parameters for the isothermal cyclic deformation analysis. Based on the previous research this paper f dther improves the isothermal parameters and suggests how to apply the isothermal parameters to the non-isothermal conditions especially for the description of TMF(Thermo-Mechanical Fatigue) hysteresis behavior. The parameters are determined and calibrated using 400 series stainless steel test data in the reference papers. For the implementation into ABAQUS, a user subroutine is developed by means of ABAQUS/UMAT. The finite element results show good agreement with test for the case of uniaxial non-isothermal cyclic loading, signifying the proposed method can be used in the TMF analysis of the converter-inserted heavy duty muffler system and the stainless steel exhaust-manifold system which are to be done in our future research.

• Journal of Pharmaceutical Investigation
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• v.20 no.1
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• pp.19-28
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• 1990

Pharmacokinetic parameters of aminoglycosides are dependent on renal function, sex, age, hematocrit, fever, lean body weight (LBW) and disease states, etc. Therefore, the individual pharmacokinetic parameters such as half life $(t^{1/2})$ and volume of distribution(Vd) are needed to achieve optimal therapy. However these parameters had not been determined in Koreans. The purpose of this study was to evaluate the Vd and $t^{1/2}$ of amikacin in Korean patients who had normal renal function, to compare the mean values of study group with that reported in the literature and to compare the measured $t^{1/2}$ with the expected $t^{1/2}$ based on actual body weight (ABW), LBW and ideal body weight (IBW), respectively. Based on data, the Vd was greater than the literature and $t^{1/2}$ was similar to the literature. The predicted $t^{1/2}$ based on IBW was the closest to actual $t^{1/2}$. And postpartum patients had greater Vd than other group and had lower correlation between actual elimination rate constant and calculated creatinine clearance but higher correlation between actual elimination rate constant and Vd than other group.

• The Transactions of the Korean Institute of Power Electronics
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• v.23 no.3
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• pp.174-181
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• 2018

This study introduces a systematic approach to selecting the internal parameters applied to the equivalent electrical-circuit model (EECM) of a lithium titanium oxide ($Li_4Ti_5O_{12}$; LTO) rechargeable cell. Based on the dynamic characteristic of the cell, a simplified EECM consisting of an open-circuit voltage (OCV), an ohmic resistance, and an RC ladder is fabricated. To select the internal parameters of a simplified EECM, experiments on discharge capacity, OCV, and discharge/charge resistances are performed using hybrid pulse power characterization and direct current internal resistance (DCIR) measurements over the full state-of-charge (SOC) range. The experimental results of the LTO rechargeable cell highlight the importance of correct selection of internal parameters that can reduce EECM errors. This study clearly provides experimental procedures, internal parameters results, and EECM guidelines for adaptive control-based SOC estimation for LTO rechargeable cells.

• Tribology and Lubricants
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• v.30 no.5
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• pp.284-290
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• 2014

The influence of round embossed surface on slider bearing characteristics and its load carrying capacity is discussed for thin film effect of embossed slider bearing. For the numerical computation of lubrication parameters such as pressure, load capacity and shear stress that are normalized and a Reynolds equation is used for the analysis of embossed slider bearing characteristics. For this purpose, the finite difference method of central difference scheme is used in this study. In a slider bearing with embossed form, several simulation parameters such as pressure, load capacity and shear stress of the bearing can be obtained according to independent parameters such as the slope of the slider bearing and number of embossing in the upper slider. Also this results can be summarized and be stored in sequential data file for latter analysis. After all, their distribution of the pressure and shear stress parameters can be displayed and be analyzed easily by using the developed program with matlab GUI technique. The independent parameters such as a number of embossing and a slope of the embossed surface slider are used for discussing simulation parameters of pressure distribution, shear stress and load carrying capacity of the round embossing. These study results reported in this paper should be applied to the other shaped slider bearing with a rectangular embossed surface or rectangular waved surface.