• 품질경영학회지
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• 제25권1호
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• pp.44-55
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• 1997

In order to determine procedures for a, pp.opriate model selection of technological growth curves, numerous time series that were representative of growth behavior were collected according to data characteristics. Three different growth curve models were fitted onto data sets in an attempt to determine which growth curve models achieved the best forecasts for types of growth data. The analysis of the results gives rise to an a, pp.oach for selecting a, pp.opriate growth curve models for a given set of data, prior to fitting the models, based on the characteristics of the goodness of fit test.

• 품질경영학회지
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• 제23권2호
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• pp.53-67
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• 1995

The problem considered here is to find the optimal discriminant analysis method in growth curve model. It has been studied how to find correct prior probability for the effective classification in discriminant analysis. We use the balanced condition to calculate prior probability. From the informative simulation study, new classification rule for the growth curve model is suggested. The suggested classification rule has better classification result than the other previously suggested method in terms of error rate criterion.

• 한국IT서비스학회지
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• 제11권3호
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• pp.89-101
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• 2012

The study investigated if IT investment in Korean financial markets for the past 18 years has grown following the s-curve pattern based on Nolan's growth model in order to find the correlation between IT investment and management performance in the financial industry. According to the research finding it can be said that the overall financial markets maintain s-curve pattern, and IT investment is related to management performance, particularly increase in total assets and net profit. However, each sector has defining features of growth patterns. The banking industry has grown similarly to the s-curve, and the insurance industry also shows the s-curve but it looks more like linear pattern. In terms of securities industry, its growth patterns can hardly be considered s-curve due to the irregular changes. his research outcome illustrates the analysis of IT growth patterns in the financial industry and thus, it is expected to be a useful reference when deciding the appropriate time for IT investment in the financial industry.

• 말소리와 음성과학
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• 제9권3호
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• pp.17-23
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• 2017

The present study investigates the effect of Accentual Phrase on F0 using a subset of large-scale corpus of Seoul Korean. Four syllable words which were neither preceded nor followed by silent pauses were presumed to be canonical exemplars of Accentual Phrases in Korean. These four syllable words were extracted from female speakers' speech samples. Growth curve analyses, combination of regression and polynomial curve fitting, were applied to the four syllable words. Four syllable words were divided into four groups depending on the categorical status of the initial segment: voiceless obstruents, voiced obstruents, sonorants, and vowels. Results of growth curve analyses indicate that initial segment types have an effect on the F0 (in semitone) in the nucleus of the initial syllable, and the cubic polynomial term revealed that some of the medial low tones in the 4 syllable words may be guided by the principle of contrast maximization, while others may be governed by the principle of ease of articulation.

• 시스템엔지니어링학술지
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• 제16권1호
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• pp.1-8
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• 2020

In this paper we proposed to develop the reliability growth planning for the One-shot system using the PM2-Discrete model. The PM2-Discrete is the methodology specifically developed for discrete systems and is the first quantitative method available for formulating detailed plans in the discrete usage domain. First, the parameters RG, RI, T, MS and d of the PM2-Discrete model are set. Second, the case analysis was performed on One-shot system A. Third, the input parameter values were applied to drive the R(t) equation. Finally, using RGA 11 Software, the reliability Growth Planning Curve of One-shot system A was constructed. Also, the sensitivity analyses are performed for the changes of model parameters. The results of this study can be usefully used in establishing the reliability growth planning curve of the One-shot system.

• 한국작물학회지
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• 제27권1호
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• pp.84-86
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• 1982

담배의 품종과 재배형별 주당 건물중의 경시적 변화를 보다 더 정밀하게 표현할 수 있는 생장곡선방정식을 수식화하기 위하여 3가지의 생장모형을 만들어서 그 타당성을 분석한 결과는 다음과 같다. 1. 담배의 건물중에 가장 적합한 생장곡선은 C형이며 이 생장곡선은Y = A + (1-$\sqrt{4AK+1}$)/2이다. 2. 이 곡선은 이식후 35-55일의 편차가 Logistic curve보다 더 작으며 정밀하다.

• 품질경영학회지
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• 제50권3호
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• pp.349-371
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• 2022

Purpose: Compared to the rapid growth rate of the domestic automotive LED industry so far, the predictive analysis method for demand forecasting or market outlook was insufficient. Accordingly, product characteristics are analyzed through the life trend of LEDs for automotive exterior lamps and the relative strengths of p and q using the Bass model. Also, future demands are predicted. Methods: We used sales data of a leading company in domestic market of automotive LEDs. Considering the autocorrelation error term of this data, parameters m, p, and q were estimated through the modified estimation method of OLS and the NLS(Nonlinear Least Squares) method, and the optimal method was selected by comparing prediction error performance such as RMSE. Future annual demands and cumulative demands were predicted through the growth curve obtained from Bass-NLS model. In addition, various nonlinear growth curve models were applied to the data to compare the Bass-NLS model with potential market demand, and an optimal model was derived. Results: From the analysis, the parameter estimation results by Bass-NLS obtained m=1338.13, p=0.0026, q=0.3003. If the current trend continues, domestic automotive LED market is predicted to reach its maximum peak in 2021 and the maximum demand is $102.23M. Potential market demand was $1338.13M. In the nonlinear growth curve model analysis, the Gompertz model was selected as the optimal model, and the potential market size was $2864.018M. Conclusion: It is expected that the Bass-NLS method will be applied to LED sales data for automotive to find out the characteristics of the relative strength of q/p of products and to be used to predict current demand and future cumulative demand.

• 한국경제지리학회지
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• 제25권4호
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• pp.629-640
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• 2022

본 연구는 2002-2020년 기간의 지역 데이터를 사용하여 지방정부규모와 지역경제성장 간의 관계를 분석하였다. 지방정부지출을 사회개발비와 경제개발비로 나누어 GRDP 성장률과 역U자 형태의 Armey 곡선의 관계가 존재하는지 검증하고, 최적의 지방정부지출의 수준을 살펴보고자 하였다. 특히, 추정방법에 있어서 패널자료에 존재하는 횡단면 의존성과 지역별 이질성을 고려한 AMG 추정법을 활용하였다. 분석 결과, 총지방재정지출 및 사회개발비의 규모와 지역경제성장 간에 역U자형 관계가 나타났고, 경제개발비와 지역경제성장 간에는 역U자형 관계가 존재하지 않는 것으로 나타났다. 총지방재정지출 비중이 GRDP 대비 7.63%일 때, 사회개발비 비중은 3.45%일 때 지역경제성장률을 극대화할 수 있는 최적의 지출규모인 것으로 나타났다. 지방정부는 이러한 점을 고려하여 공공지출 정책의 실효성을 높여야 한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.702-709
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• 2004

Modified Gurson model (Gurson-Tvergaard-Needleman model) was used to analyze crack growth in M(T) and C(T) specimens. A commercial finite element code ABAQUS/Explicit is used to account for total failure of material point by cavity coalescence, and crack growth was simulated by finite element extinction. Crack growth resistance curve was obtained by calculating J-integral. Crack growth under residual stress was investigated.

• Asian-Australasian Journal of Animal Sciences
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• 제11권1호
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• pp.84-88
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• 1998

The aim of this study was to describe growth patterns of mice using Gompertz model. Two distinct types of mice, laboratory mouse $CF_{\sharp1}$ (Mus musculus domesticus) and Yonakuni wild mouse (Yk, Mus musculus molossinus yonakuni) were used. From all possible crosses, there were two parental types and two reciprocal $F_1$ crosses obtained. Individual body weights were measured weekly from birth to ten weeks of age on 321 mice. Standardization to six mice was conducted and only first litters were used. Growth curve parameters were estimated to fit growth data. The results showed that growth among genetic groups were significantly different (p < 0.05) for both sexes, in which parental type of $CF_{\sharp1}$ and Yk had the highest and the smallest values, respectively. Meanwhile, reciprocal $F_1$ crosses were intermediate between parental types. It was concluded that Gompertz model provided and excellent fit for the growth data with a high coefficient determination $(R^2 = 0.999)$.