• KIPS Transactions on Software and Data Engineering
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• v.2 no.11
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• pp.739-746
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• 2013

Variability of the software product line that differentiates member products within a product line must be described with precise meaning and visualized so as easy to select. Moreover, it should be easy to manage. Variability description approaches can largely be divided into two approaches, integrated variability description approach and orthogonal variability description approach. Orthogonal Variability Description Language (OVDL) was developed for clear and precise description of variability without ambiguity. This paper validates the variability description capability of OVDL by translating the variability models of Inter-Working Function (IWF) product line described by using Orthogonal Variability Model (OVM) notations into variability descriptions in OVDL.

• School Mathematics
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• v.14 no.4
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• pp.495-516
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• 2012

This study distinguished thinking related to statistical variability into six components - the noticing of variability, the explanation of variability, the control of variability, the modeling of variability, the understanding of samples, and the understanding of sampling distribution and investigated the relationships among the thinking components. This study found that this distinction of thinking components related to statistical variability is reasonable. The results showed that each correlation coefficient of the modeling of variability, the understanding of samples, and the understanding of sampling distribution with regard to the noticing of variability, the explanation of variability, and the control of variability is similar. Based on this results, new variable, the understanding of sampling, has been drawn. The results also showed that while the noticing of variability and the control of variability influence the understanding of sampling, the explanation of variability does not influence it.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.215-216
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• 2007

• Journal of KIISE:Software and Applications
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• v.30 no.5_6
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• pp.414-429
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• 2003

Component-based development(CBD) has been generalized in industry to master the complexity and reduce the development cost and time. However, current CBD practice is developing the component which is dependent on single application[l][2]. Therefore component variability is emphasized to reuse the component in many family members in a domain[8]. However, components are developed for the reason of replaceability rather than the reusability which is the main purpose of the component due to the insufficiency of the study of component variability definition and type[3]. In this paper, we formally specify the component variability reflecting the characteristics of the component to increase the component reusability. We define the logic variability which was recognized as the existing component variability and we propose all types of variability existing in the component by suggesting three more variability types. And we propose the component variability scope which makes us estimate and verify the number of cases of the variability when we customize the component. We propose these component variability types and scope through formal specification. By applying these techniques in developing components, we can develop high quality components reusable in many family members.

• Journal of Oriental Neuropsychiatry
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• v.27 no.2
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• pp.89-101
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• 2016

Objectives In human, there is a diversity in the breathing pattern, for instance inspiratory and expiratory time, volume, breathing frequency, and breath-to-breath variation. Expecially, respiratory variability can provide important information about breathing regulation and physiological flexibility. it is significant to not only breathing index but also physiological index.Methods Thus this paper reviews the literature on respiratory variability with the aim of clinical application.Results We could find the interrelationships and respiratory variability between emotions, psychopathy, sighing, mental and physical activity.Conclusions As a result, respiratory variability can serve an important physiological index in the clinical area and reflects how our bodies act in diverse environments under various condition.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.12 no.2
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• pp.74-83
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• 2008

Background and purpose : Health is characterized by variability, and the loss of variability is associated with aging and disease. Normal healthy respiratory patterns are characterized by breath to breath variability. Cold-Heat scores are quantified indices in Korean Medicine. The aim of this study is to analyze relations between 9 respiratory indices (including breath to breath variability) and HRV(heart rate variability). Method : Respiratory data were measured during a period of 15 minutes and transferred to text file. We calculated 9 respiratory parameters using MATLAB 7.1. Afterwards we did correlation analysis of the 9 respiratory indices and HRV. Results and conclusion : Respiratory variability showed significant correlation with HRV.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1435-1440
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• 2009

Geotechnical variability is a complex feature that results from many independent sources of uncertainties, and is mainly affected by inherent variability and measurement errors. This study evaluates the coefficient of variation (COV) of soil properties at Song-do region in Korea for evaluating inherent soil variability. Since soil variability is sensitive to soil layers and soil types, the COVs by soil layers (reclaimed layer and marine layer) and the COVs by soil types (clay and silt) were separately evaluated. It is observed that geotechnical variability of marine layer and clay is relatively smaller than that of reclamation layer and silt.

• Korean Journal of Applied Biomechanics
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• v.24 no.4
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• pp.359-365
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• 2014

A study was conducted to investigate the possible effects of fatigue which was resulted from increased running time on the stability during a prolonged run. The purposes of this study were twofold: first, to determine the discrete and non-linear variability of GRF (ground reaction force) components between running times to know the body stability, and second, to determine the pattern between discrete and non-linear variability. Nineteens healthy young adult males served in this study as subjects who ran at their preferred running speed. GRF data for twenty strides were collected at 5, 65, and 125 minutes during run. Variance coefficient and Lyapunov Exponent techniques on the GRF data were used to calculate variability index for each of the running time conditions. There were no difference between discrete variabilities of three components of GRF, but non-linear variability of the Fz component of GRF was decreased by increasing running time (p<.01). No relationship was found between discrete and non-linear variability.

• Korean Journal of Applied Biomechanics
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• v.18 no.4
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• pp.49-57
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• 2008

The purpose of this study was to determine the effects of 12-week elastic resistance exercise for the elderly on the magnitude of frequency and variability of ground reaction force signals. To this aim, total 12 elderly women aged in their 70 were participated in this study and asked to do a 12-week elastic resistance exercise program. FFT(fast Fourier Transform) was used to analyze the frequency domain analysis of the ground reaction forces's signals and an accumulative PSD (power spectrum density) normalized by support phase of walking was calculated to reconstruct the certain signals. To estimate the gait stability between the before and after exercise, values of variability were determined in a coefficient of variance. The magnitude of frequency and variability analysis for media-lateral signal revealed significantly less after exercise (p<.05). In contrast, variability of this signal's frequency that have used to evaluate the local stability during walking exhibited significantly greater after exercise(p<.05). In summary, magnitude frequency and variability of media-lateral ground reaction force's signal were significantly changed after a 12-week elastic resistance exercise.

• Journal of Educational Research in Mathematics
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• v.20 no.4
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• pp.493-509
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• 2010

Researchers have suggested that educators have to focus their attention on variability and reasoning about variation as means of developing students' statistical thinking in school mathematics. This paper investigated knowledge for the teaching of variability and reasoning about variation; what are sources of variability, how to cope with variability, what are types of variability, how to recognize variability, and the relationship between statistical problem solving and variability. The results involve: discussion on the sources of variability and how to cope with variability promotes students' awareness of different types of variability and students' motivation in the following steps in the statistical activity; emphasis on reasoning about variation in teaching representation of data accords with objectives of statistics education; reexamination of curriculum for statistics education is needed, which has a content-oriented arrangement.