• 제어로봇시스템학회:학술대회논문집
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• 1994.10a
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• pp.13-20
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• 1994

The spectrum estimation methods of random processes are expressed in this paper. Beginning with the basic theory, non-parametric and parametric methods are overviewed. As to non-parametric method, numerical calculation method is also discussed. As to parametric method, AR model is a very famous and effective model representing random process. Estimation methods of AR parameters which have been proposed are mentioned here. Wavelet analysis is a recently interested technique in signal processing. An application of wavelet analysis is also shown.

• Journal of the Korean Data and Information Science Society
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• v.18 no.2
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• pp.411-418
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• 2007

Sample size calculation is very important in clinical trials. In this paper, we propose sample size calculation method for non-inferiority trials using sample size calculation method suggested by Wang et al.(2003) based on Wilcoxon's rank sum test. Also, sample size comparison between parametric method and proposed method are presented.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.684-689
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• 2005

Parametric calculation were conducted to estimate performance of variable geometry of hydrogen recirculation blower for fuel cell vehicle. The pressure rise and efficiency are effected by change of the geometric parameter of impeller and casing, and stripper clearance under various mass flow. Hydrodynamic performance were evaluated, and also the inner flow fields were investigated by CFD. Calculated results show good coincidence with experimental test results of total pressure performance. Performance of model designed by parametric calculations satisfied experimental data of verification model.

• Korean Institute of Interior Design Journal
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• v.19 no.1
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• pp.137-147
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• 2010

The purpose of this study is to research a method of creating a new type of boundary by repeated disposition of single unit of modularized membrane successively. In the contemporary architectural indoor space, more highly dimensional analysis of boundary is required and the necessity of establishing boundary of a new concept that may satisfy cultural value, social value and artistic value as a whole as well as aesthetic and functional merit has been increased. In order to create a membrane that may fulfil the requirements of the diversified programs of space like this, an approach of complicated mechanism and high-dimensional calculation are required. At this time, digital GA modelling, parametric modelling technique may expand its range of possibility. One thing to be noted at this juncture is that indefinite expandability involved in digital modelling technique, modelling by grid of absolute and relative coordinates and convenience of systematization may surpass limitation of analogue or simple numerical calculation being progressed in the past. And in order to create solid process including unit modelling or pattern formation, Precise calculation process of computer is necessitated inevitably.

• Steel and Composite Structures
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• v.26 no.5
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• pp.595-606
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• 2018

A calculation method was presented to calculate the deflection of GFRP-concrete-steel beams with full or partial shear connections. First, the sectional analysis method was improved by considering concrete nonlinearity and shear connection stiffness variation along the beam direction. Then the equivalent slip strain was used to take into consideration of variable cross-sections. Experiments and nonlinear finite element analysis were performed to validate the calculation method. The experimental results showed the deflection of composite beams could be accurately predicted by using the theoretical model or the finite element simulation. Furthermore, more finite element models were established to verify the accuracy of the theoretical model, which included different GFRP plates and different numbers of shear connectors. The theoretical results agreed well with the numerical results. In addition, parametric studies using theoretical method were also performed to find out the effect of parameters on the deflection. Based on the parametric studies, a simplified calculation formula of GFRP-concrete-steel composite beam was exhibited. In general, the calculation method could provide a more accurate theoretical result without complex finite element simulation, and serve for the further study of continuous GFRP-concrete-steel composite beams.

• Communications of the Korean Mathematical Society
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• v.28 no.3
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• pp.635-642
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• 2013

There are many results on the extended operations of two fuzzy numbers based on the Zadeh's extension principle. For the calculation, we have to use existing operations between two ${\alpha}$-cuts. In this paper, we define parametric operations between two ${\alpha}$-cuts which are different from the existing operations. But we have the same results as the extended operations of Zadeh's principle.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1128-1131
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• 1996

The collision-free path planning presented here uses linear parametric curve with one intermediate connection point between start and target points. The algorithm, in which connection point is organized in elliptic chord.(.theta., .delta.), maps objects in Euclidean Space into images in CPS through intersection check between path and obstacles a process defined as GM. Elliptic locus has special property that the total distance between focus points through a point on ellipse is the same regardless of .theta.. Hence by locating the start and target points to focus points of ellipse, and organizing connection point in elliptic coordinate, the .delta.-axis of CPS represents length of path. The GM of EWS requires calculation of interference in circumferential direction only. The procedures for GM is developed which include categorization of obstacles to reduce calculation amount. Simulations of GM of EWS, on a PC with Pentium/90MHz, is carried out to measure performance of algorithm and the results are reported on a table. The simulations are done for number of cases with different number of obstacles and location of start/target points.

• 한국전산유체공학회:학술대회논문집
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• 2002.05a
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• pp.88-93
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• 2002

In the present research, a parametric study of aerodynamic characteristics for multi-element airfoils is performed. The major geometric parameters of interest are the gap distance between airfoils and relative deflection angle of slat/flap. The present results are mainly obtained by using inviscid flow calculation, and the aerodynamic characteristics are focused on the surface pressure distribution and the lifts. The results of the present research may be used as not only qualitative data but also quantitative data for small angle of attack flows, where the viscous effect does not play major role in terms of surface pressure distribution and lifts. A further research in this subject including viscous calculation and more geometric parameters is to be performed in the future.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.3
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• pp.43-50
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• 2006

In this successive study, the analytical realization of coupled system was introduced using the times series identification and spectrum analysis, which was compared with conventional FFT spectrum. Also, the numerical responses of second order system, which is coupled, were solved using the numerical calculation of Runge-Kutta Gill method. After numerical analysis, the displacement, velocity and acceleration were acquired. Among them, the response of displacement was used for the analysis of time series spectrum. Among several time series, the ARMAX algorithm was proved to be appropriate for the spectrum analysis of the coupled system. Using the separated response of 1st and 2nd mode, the mode was calculated separately. And the responses of mixed modes were also analyzed for calculation of the mixed modes in the coupled system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1992.03a
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• pp.131-158
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• 1992

Verification, calibration, and compensation are becoming more essential elements for manufacture and maintenance of high performance CMMs. A computer module of volumetric error generation has been developed to calculate volumetric errors (random as well as systematic) from measured parametric errors, accepting most types of CMMs in current use. New transformation rules have been derived to transform all the parametric errors with respect to the origin of working volume considered, then incorporated, then incorporated into the module of error calculation. Two cases of practical CMMs are tested with the developed module, and showed good performance.