• Convergence Security Journal
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• v.12 no.3
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• pp.115-121
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• 2012

Software failure time presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing. For data analysis of software reliability model, data scale tools of trend analysis are developed. The methods of trend analysis are arithmetic mean test and Laplace trend test. Trend analysis only offers information of outline content. In this paper, we discuss forecasting failure time case of failure time censoring. In this study, we predict the future failure time by using the curve regression analysis where the s-curve, growth, and Logistic model is used. The proposed prediction method analysis used failure time for the prediction of this model. Model selection using the coefficient of determination and the mean square error were presented for effective comparison.

• Journal of applied mathematics & informatics
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• v.8 no.3
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• pp.731-742
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• 2001

A Gaussian smoothing algorithm obtained from a cascade of convolutions with a seven-point kernel is described. We prove that the change of local sums after applying our algorithm to sinusoidal signals is reduced to about two thirds of the change by the binomial coefficients. Hence, our seven point kernel is better than the binomial coefficients when trend curves are needed to be generated. We also prove that if our Gaussian convolution is applied to sinusoidal functions, the amplitude of higher frequencies reduces faster than the lower frequencies and hence that it is a low pass filter.

• Korea journal of population studies
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• v.23 no.1
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• pp.197-215
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• 2000

이 논문에서는 선형·비선형 성장곡선모형의 종류와 특성을 살펴보고, 이들을 비교·검토하고, 모형선호기준 통계량에 입각하여 추정결과를 비교한다. 또한 최종사용자 환경을 위한 SAS/AF로 구현한 성장곡선모형에 의한 인구예측시스템을 소개한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.177-184
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• 2017

Understanding trends and drivers of technology diffusion is imperative to forecast new technology adoption and understand the process of technological innovation. Our research utilizes a quantitative trend analysis considering both technological and economic indicators for trends and drivers of technology diffusion for 32nm, 22nm, and 14nm logic semiconductor technology. In terms of technological performance, the technology diffusion curve showed an S-curve pattern during the stages of maturity and decline, and the diffusion curve showed evidence supporting the learning curve. The diffusion curve showed the life cycle duration of 2 years, and the rate of technological performance and obsolescence are observed quantitatively between generations. Architectural innovation is affected by technological drivers more significantly than economic drivers. This research has implications as empirical research on the trends and drivers of technology diffusion in the high-tech semiconductor industry, and is meaningful in forecasting new technology adoption or build technology strategy.

• Journal of the Korean Society of Costume
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• v.50 no.2
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• pp.167-182
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• 2000

The purpose of this study is to examine the art nouveau fashion represented in the end of the twentieth century. The characteristics of art nouveau are naturalism, medievalism , exoticism, and decadentism. The influences of art nouveau were seen in the fashion of the late nineteenth century : S-curve silhouette and organic curve motives printed on hems. Art nouveau has reappeared in modern fashion trends such as romanticism , decadence, ecology, ethno, and fusion. To sum up, art nouveau fashion at the end of the twentieth century is classified into four shapes. First, art nouveau appears in naturalism. Influenced by the arts and crafts movements and naturalistic trend, it has reappeared at the end of the twentieth century in themes like 'art & craft'. This expression technique is to objectively nature and to represented art nouveau textiles. Second, S-curve silhouette appeared at the end of nineteenth century's fashion with the art nouveau influenced rejection of the bustle style. At the end of the twentieth century, the design , emphasizing the hip, is represented in fashion collections as a phenomenon of romanticism . Especially the art nouveau silhouette of the end of the twentieth century does not represent S-curve silhouette. But , it emphasizes the hip only. Third, Art nouveau exoticism by symbolism is influenced by Chinese and Celtic art, the Middle Ages, and the exoticism that appeared in fashion at the end of the nineteenth century : harem style, kimono style, and turbans. Exoticism at the end of the twentieth century is expressed by optical flower prints and successive floral print arrangements as seen in the themes of ethno and fusion. Fourth, one of the characteristics of art nouveau, decadence is influenced by the pre-raphaelite brotherhood. This is expressed in the images of vampires, and symbolism expressing grotesque insect motives and decadent successive curves. At the end of the twentieth century decadence is represented in fashion ; grotesque insect motives, tatto looks of organic curve motives celtic hair style, see-through fashion, grotesque make-up . Besides hair style techniques, decadent expressions applying art nouveau paintings also appeared. Finally , art nouveau fashion represented as a fashion trend at the turning point to the new millennium is one of great significance as an organic, an environment-intimate and continuance-possible design in a future.

• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.2844-2853
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• 2023

A sophisticated Bayesian multilevel model for estimating group bias was developed to improve the utility of the ASTM E900-15 embrittlement trend curve (ETC) to assess the conditions of nuclear power plants (NPPs). For multilevel model development, the Baseline 22 surveillance dataset was basically classified into groups based on the NPP name, product form, and notch orientation. By including the notch direction in the grouping criteria, the developed model could account for TTS differences among NPP groups with different notch orientations, which have not been considered in previous ETCs. The parameters of the multilevel model and biases of the NPP groups were calculated using the Markov Chain Monte Carlo method. As the number of data points within a group increased, the group bias approached the mean residual, resulting in reduced credible intervals of the mean, and vice versa. Even when the number of surveillance test data points was less than three, the multilevel model could estimate appropriate biases without overfitting. The model also allowed for a quantitative estimate of the changes in the bias and prediction interval that occurred as a result of adding more surveillance test data. The biases estimated through the multilevel model significantly improved the performance of E900-15.

• Journal of Korean Institute of Industrial Engineers
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• v.7 no.2
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• pp.27-41
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• 1981

The purpose of this study is to extract and classify the general patterns on scientific and technological development by quantitative approaches. Indicators used for this pattern classification amounted to a total of 39. what is more, these indicators were set up with the recent data for the first half of the 1970's mainly, and 141 nations were selected as the sample of the analysis. 7 aspects which prescribe the scentific and technological activities were established, and so 3 patterns of the S & T development were extrected by means of a "two-dimensional cross section" among them. (1) A pattern showing the trend of the exponential curve from the point over a certain level (in this study, it is defined as "Threshold Valued"). (2) A pattern in which elasticity of the exponential curve is gradually reduced from the point over the threshold value. (3) A pattern not showing any trend, but forming a large variance.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.1
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• pp.22-32
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• 2007

This paper describes a study of a helicopter database for the sizing stage of a preliminary design process. The database includes specifications and performance parameters for more than 150 conventional single rotor helicopters currently in market. Design parameters, including configuration and weight parameters, have been analyzed and trend curve equations(regression equations) are derived using the regression analysis method. Finally, the applicability of this research result was verified whether the method is reliable for being adopted as a useful design tool in the early stage of a helicopter design process.

• Electrical & Electronic Materials
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• v.7 no.2
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• pp.107-116
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• 1994

In the manufacturing of VLSI circuits, variations of device characteristics due to the slight differences in process parameters drastically aggravate the performances of fabricated devices. Therefore, it is very important to establish optimal process conditions in order to minimize deviations of device characteristics. In this paper, we used one-dimensional process simulator, SUPREM-II, and two dimensional device simulator, MINIMOS 4.0 in order to extract optimal process parameter which can minimize changes of the device characteristics caused by process parameter variation in the case of short channel nMOSFET and pMOSFET device. From this simulation, we have derived the dependence relations between process parameters and device characteristics. Here, we have suggested a method to extract process parameters from design trend curve(DTC) obtained by these dependence relations. And we have discussed short channel effects and device limitations by scaling down MOSFET dimensions.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.34 no.10
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• pp.389-398
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• 1985

Recently maximum power demand of our country has become to be under the great in fluence of electric cooling and air conditioning demand which are sensitive to weather conditions. This paper presents the technique and algorithm to forecast the long-term maximum power demand considering the characteristics of electric power and weather variable. By introducing a weather load model for forecasting long-term maximum power demand with the recent statistic data of power demand, annual maximum power demand is separated into two parts such as the base load component, affected little by weather, and the weather sensitive load component by means of multi-regression analysis method. And we derive the growth trend regression equations of above two components and their individual coefficients, the maximum power demand of each forecasting year can be forecasted with the sum of above two components. In this case we use the coincident dry bulb temperature as the weather variable at the occurence of one-day maximum power demand. As the growth trend regression equation we choose an exponential trend curve for the base load component, and real quadratic curve for the weather sensitive load component. The validity of the forecasting technique and algorithm proposed in this paper is proved by the case study for the present Korean power system.