Sangyeol Lee

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Although the prevalence of insomnia and the association of insomnia with menopause have been well reported, not much work has been conducted in population-based research on insomnia and menopause in Korea. The purpose of the present report was to determine overall and different prevalence of insomnia by menopausal status, and the relationship between(More)
An atlas provides a reference anatomic structure and an associated coordinate system. An atlas may be used in a variety of applications, including segmentation and registration, and can be used to characterize anatomy across a population. We present a method for generating an atlas of the human retina from 500 color fundus image pairs. Using color fundus(More)
Fundus camera imaging of the retina is widely used to diagnose and manage ophthalmologic disorders including diabetic retinopathy, glaucoma, and age-related macular degeneration. Retinal images typically have a limited field of view, and multiple images can be joined together using an image registration technique to form a montage with a larger field of(More)
We study the validity of the Jarque-Bera test for a class of univariate parametric stochastic differential equations (SDE) dXt = b(Xt, α)dt+ dZt observed at discrete time points t n i = ihn, i = 1, 2, . . . , n, where Z is a nondegenerate Lévy process with finite moments, and nhn → ∞ and nhn → 0 as n → ∞. Under appropriate conditions it is shown that(More)
Fundus camera imaging of the retina is widely used to document ophthalmologic disorders including diabetic retinopathy, glaucoma, and age-related macular degeneration. The retinal images typically have a limited field of view due mainly to the curvedness of human retina, so multiple images are to be joined together using image registration technique to form(More)
In this paper we consider the problem of testing for a parameter change in regression models with ARCH errors based on the residual cusum test. It is shown that the limiting distribution of the residual cusum test statistic is the sup of a Brownian bridge. Through a simulation study, it is demonstrated that the proposed test circumvents the drawbacks of(More)