• Toxicological Research
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• v.20 no.2
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• pp.89-100
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• 2004

The comet assay (also called the single-cell gel electrophoresis assay) has been widely used for detecting DNA damage and repair in individual cells. Since the conventional methods of evaluating comet assay data using frequency statistics are unsatisfactory we developed a new quantitative measure of DNA damage/repair that is based on all information residing in the dose/time-response curves of a comet experiment. Blood samples were taken from 25 breast cancer patients before undergoing radiotherapy. The comet assay was performed under alkaline conditions using isolated lymphocytes. Tail DNA, tail length, tail moment and tail inertia of the comet were measured for each patient at four doses of $\gamma$-rays (0, 2, 4 and 8 Gy) and at four time points after irradiation (0, 10, 20 and 30 min) using 100 cells each. The resulting three-dimensional dose-time response surface was modeled by multiple regression, and the second derivative, termed 2D, on dose and time was determined. A software module was programmed in SAS/AF to compute 2D values. We applied the new method successfully to data obtained from cancer patients to be assessed for their radiation sensitivity. We computed the 2D values for the four damage measures, i.e., tail moment, tail length, tail DNA and tail inertia, and examined the pairwise correlation coefficients of 2D both on the log scale and the unlogged scale. 2D values based on tail moment and tail DNA showed a high correlation and, therefore, these two damage measures can be used interchangeably as far as DNA repair is concerned. 2D values based on tail inertia have a correlation profile different from the other 2D values which may reflect different facets of DNA damage/repair. Using the dose-time response surface, other statistical models, e.g., the proportional hazards model, become applicable for data analysis. The 2D approach can be applied to all DNA repair measures, Le., tail moment, tail length, tail DNA and tail inertia, and appears to be superior to conventional evaluation methods as it integrates all data of the dose/time-response curves of a comet assay.

• PNF and Movement
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• v.13 no.3
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• pp.119-125
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• 2015

Purpose: The current study seeks to examine the effects of stabilizing reversal(SR) and rhythmic stabilization(RS) in proprioceptive neuromuscular facilitation (PNF) techniques on static balance in normal female adults. Methods: Subjects included 20 healthy women in their 20s. They were randomly divided into SR and RS groups. To assess static balance before and after PNF intervention, the good balance system was used to measure the interior and exterior center of pressure (COP) movement distance, front and rear COP movement distance before and after the intervention, and velocity moment. Results: Interior and exterior COP movement distance, front and rear COP movement distance, and velocity moment decreased in the SR group, but no statistically significant differences were observed. In the RS group, the interior and exterior COP movement distance declined without any significant difference, while the front and rear COP movement distance and velocity moment significantly decreased. The interior and exterior COP movement distance, front and rear COP movement distance, and velocity moment declined more in the RS group than in the SR group. Conclusion: The findings of the current study indicate that the RS technique is more effective than the SR technique for improving the balance ability of healthy female adults. The results of this study can thus be utilized in the selection of effective interventions for improving the balance ability of healthy female adults.

• Computational Structural Engineering : An International Journal
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• v.1 no.2
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• pp.81-87
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• 2001

A framework for reliability analysis of structural components and systems under conditions of statistical and model uncertainty is presented. The Bayesian parameter estimation method is used to derive the posterior distribution of model parameters reflecting epistemic uncertainties. Point, predictive and bound estimates of reliability accounting for parameter uncertainties are derived. The bounds estimates explicitly reflect the effect of epistemic uncertainties on the reliability measure. These developments are enhance-ments of second-moment uncertainty analysis methods developed by A. H-S. Ang and others three decades ago.

• Journal of the Korean Statistical Society
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• v.24 no.1
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• pp.183-195
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• 1995

For a distribution on the unit sphere, the set of eigenvectors of the second moment matrix is a conventional measure of orientation. Asymptotic confidence cones for eigenvector under the parametric assumptions for the underlying distributions and nonparametric confidence cones for eigenvector based on bootstrapping were proposed. In this paper, to reduce the level error of confidence cones for eigenvector, double bootstrap confidence cones based on prepivoting are considered, and the consistency of this method is discussed. We compare the perfomances of double bootstrap method with the others by Monte Carlo simulations.

• Communications for Statistical Applications and Methods
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• v.12 no.1
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• pp.253-264
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• 2005

Hader and Park(l978) suggested the concept of slope-rotatability in axial directions for second order response surface designs. In this paper, the moment conditions for slope-rotatability in axial directions are shown and the measures for evaluating slope-rotatability in axial directions are proposed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.12 no.20
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• pp.71-76
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• 1989

In this paper, GERT network in modeled to improve the network of manufacturing process with feedback loop. A lot of Information on the GERT network can be derived from the equivalent W-function and MGF(moment generating function) using Mason's rule. These equations are used in calculating the variations of the performance measure and in improving the system performance. System improvement in manufacturing process is achieved by increasing the equivalent probabilities of each branches and by decreasing the expected equivalent time.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.11 no.4
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• pp.47-54
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• 2007

In [6] some computation of spectral measures induced by normal operators $T^{*n}T^n$ was introduced. In this note we improve some computations by using spectral measures, which are related t o extremal vectors. Also, we discuss the extremal value properties and apply our spectral measure equations to moment sequences which are induced by weighted shifts.

• Communications of the Korean Mathematical Society
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• v.11 no.1
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• pp.265-272
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• 1996

In this note we prove a functional central limit theorem for linearly positive quadrant dependent(LPQD) random fields, satisfying some assumption on covariances and the moment condition $\sup_{n \in \Zeta^d} E$\mid$S_n$\mid$^{2+\rho} < \infty$ for some $\rho > 0$. We also apply this notion to random measures.

• Journal of the Korean Statistical Society
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• v.5 no.2
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• pp.101-107
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• 1976

One of the important properties of a 'good' response surface design is that the design should be insensitive to wild observations. In this note, a measure of sensitivity to wild observations is studied. It is shown that designs are made robust to wild observations by making $Tr[X'X)^{-1}M]$ small where M is a moment matrix over some region of interest. The proposed criterion is compared with that suggested by Box and Draper. Some about robust two-variable response surface designs are given.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.455-458
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• 1999

It has been known that buildings having inappropriate expansion joints in their spacings may be subject to exterior damages due to extensive cracks on the outer walls under service loads, and structural damages due to excessive moment induced by temperature changes at ultimate load conditions. Rather inconsistent code provisions are available regarding spacings of expansion joints from different foreign structural codes and even worse, no quantiative measure on spacings is given in our codes for building structures. In order to establish a rational measure on the spacing of expansion joints, theoretical approaches are taken in this study. The developed theoretical formula is, then, converted to design chart for structural designer's convenience in its use. The chart considers both service and ultimate load stages.