• 품질경영학회지
• /
• 제31권1호
• /
• pp.132-141
• /
• 2003

As the technology has improved and demands of customers have varied, a lot of products are getting diverse and intricate. Consequently, the enterprise that produce products have to simultaneously consider the various variables for the very products. There are some scheme, such as Multivariate control chart and Demerit control chart, designed to simultaneously monitor the variables in the process. In this paper, we present an effective method for process control using the Demerit-CUSUM control chart in the process where nonconforming units or nonconformities are occured by various types. In addition, we show interpretation method for abnormal signal in order to quickly detect the assignable causes as Demerit-CUSUM control chart signals abnormality. we compare performance of Demerit control chart and Demerit-CUSUM control chart using example again used in the existing studies, and present result of performance accoriding to changing sample size and parameter.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2002년도 춘계학술대회 및 임시총회
• /
• pp.175-178
• /
• 2002

The proposed immune algorithm has an uncomplicated structure and memory-cell mechanism as the optimization algorithm which imitates the principle of humoral immune response, and has been used as methods to solve parameter optimization problems. Up to now, the applications of immune algorithm have been optimization problems with non-varying system parameters. Therefore, the effect of memory-cell mechanism, which is a merit of immune algorithm, is without. this paper proposes the immune algorithm using a memory-cell mechanism which can be the application of system with nonlinear varying parameters. To verified performance of the proposed immune algorithm, the speed control of nonlinear DC motor are performed. Computer simulation studies show that the proposed immune algorithm has a fast convergence speed and a good control performances under the varying system parameters.

• 한국환경과학회지
• /
• 제8권2호
• /
• pp.211-219
• /
• 1999

Surface complexation models(SCMs) have been performed to predict metal ion adsorption behavior onto the mineral surface. Application of SCMs, however, requires a self-consistent approach to determine model parameter values. In this paper, in order to determine the metal ion adsorption parameters for the triple layer model(TLM) version of the SCM, we used the zeta potential data for Zeolite and Kaolinite, and the metal ion adsorption data for Pb(II) and Cd(II). Fitting parameters determined for the modeling were as follows ; total site concentration, site density, specific surface area, surface acidity constants, etc. Zeta potential as a new approach other than the acidic-alkalimetric titration method was adopted for simulation of adsorption phenomena. Some fitting parameters were determined by the trial and error method. Modeling approach was successful in quantitatively simulating adsorption behavior under various geochemical conditions.

• Journal of the Korean Data and Information Science Society
• /
• 제21권1호
• /
• pp.179-183
• /
• 2010

In this paper, we consider the change point problem in diusion processes based on discretely observed sample. Particularly, we consider the change point test for the dispersion parameter when the drift has unknown parameters. In performing a test, we employ the cusum of squares test based on the residuals. It is shown that the test has a limiting distribution of the sup of a Brownian bridge. A simulation result as to the Ornstein-Uhlenbeck process is provided for illustration. It demonstrates the validity of our test.

• International Journal of Aeronautical and Space Sciences
• /
• 제13권2호
• /
• pp.199-209
• /
• 2012

An advanced aeroelastic formulation for flutter analyses is presented in this paper. Refined 1D structural models were coupled with the doublet lattice method, and the g-method was used for flutter analyses. Structural models were developed in the framework of the Carrera Unified Formulation (CUF). Higher-order 1D structural models were obtained by using Taylor-like expansions of the cross-section displacement field of the structure. The order (N) of the expansion was considered as a free parameter since it can be arbitrarily chosen as an input of the analysis. Convergence studies on the order of the structural model can be straightforwardly conducted in order to establish the proper 1D structural model for a given problem. Flutter analyses were conducted on several wing configurations and the results were compared to those from literature. Results show the enhanced capabilities of CUF 1D in dealing with the flutter analysis of typical wing structures with high accuracy and low computational costs.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제2권1호
• /
• pp.79-81
• /
• 2001

A study was conducted to establish the degree of genetic divergence between different hybrid forms and rearing conditions through estimation of the minimum number of genes (allelic pairs) differentiating parents in terms of specific quantitative traits. It was established that the minimum gene numbers differentiating parental lines in the inheritance of cocoon was 1, of cocoon shell weight- between 1 and 2, and of silk filament length- between 2 and 3. The variability in the specific genetic parameter could be explained by the reliability of the statistical-and-genetic method used and the expression of genes affecting the formation of each of the characters tested. Gene expression, in its turns is conditioned both by the gene interaction within the genotypes and the different genotype response to environmental change. To go deep in the problem, experiments should be conducted under strictly controlled conditions, reducing the mathematical-and-genetic analysis to a physiological levels and hence to analyse the genetic nature of the specific quantitative character formation and its genetic control.

• 유변학
• /
• 제9권2호
• /
• pp.53-59
• /
• 1997

열방성 액정고분자(LCP)와 polycarbonate(PC) poly(ether imide) (PEI) poly(PEEK), polysulfone(PSF), 그리고 polyarylsulfone(PAS)과의 블렌드에 대한 상용성을 연구하였다. 제조된 블렌드의 상거동에서 액정고분자가 PC-, PEI-, PEEK-, PSF-, 그리고 PAS-rich 상 에 녹아 들어가는 양이 PC, PEI, PEEK, PSF, 그리고 PAS가 액정 고분자 -rich상에 녹아들 어가는 양보다 많음을 알수 있었다. 측정된 블렌드의 유리전이온도 결과로부터 PC, PEI, PEEK와 액정고분자 사이의 상용성이 PSF, PAS와 액정 고분자 사이의 상용성에 비하여 더 좋음을 알수 있었다. 액정 고분자의 이방성을 고려하여 고분자-고분자 상호작용계수($\chi$12)를 결정하였으며, PC, PEI, PEEK, PSF, 그리고 PAS를 포함한 액정 고분자 블렌드에서 $\chi$12는 0.078-0.183으로 나타났다.

• 품질경영학회지
• /
• 제39권3호
• /
• pp.377-390
• /
• 2011

A common problem encountered in product or process design is the selection of optimal parameter levels which involves simultaneous consideration of multiple response variables. This is called a multiresponse problem. A multiresponse problem is solved through three major stages: data collection, model building, and optimization. Up to date, various methods have been proposed for the optimization, including the desirability function approach and loss function approach. In this paper, the existing studies in multiresponse optimization are reviewed and a future research direction is then proposed.

• Communications for Statistical Applications and Methods
• /
• 제15권6호
• /
• pp.993-1002
• /
• 2008

Correlated responses have been widely analyzed since Liang and Zeger (1986) introduced the famous Generalized Estimating Equations(GEE). However, their variance functions were restricted to known quantifies multiplied by scale parameter. In so many industries and academic/research fields, power-of-the-mean variance function is one of the common variance function. We suggest GEE-type pseudolikelihood estimation based on the power-of-the-mean variance using existing software and investigate it's efficiency for different working correlation matrices.

• Communications for Statistical Applications and Methods
• /
• 제15권6호
• /
• pp.1003-1011
• /
• 2008

Mixed-effect Poisson regression models are widely used for analysis of correlated count data such as those found in longitudinal studies. In this paper, we consider kernel extensions with semiparametric fixed effects and parametric random effects. The estimation is through the penalized likelihood method based on kernel trick and our focus is on the efficient computation and the effective hyperparameter selection. For the selection of hyperparameters, cross-validation techniques are employed. Examples illustrating usage and features of the proposed method are provided.