• Journal of applied mathematics & informatics
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• v.24 no.1_2
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• pp.179-190
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• 2007

In this paper, we consider the general variational inequality GVI(F, g, C), where F and g are mappings from a Hilbert space into itself and C is the fixed point set of a nonexpansive mapping. We suggest and analyze a new modified hybrid steepest-descent method of type method $u_{n+l}=(1-{\alpha}+{\theta}_{n+1})Tu_n+{\alpha}u_n-{\theta}_{n+1g}(Tu_n)-{\lambda}_{n+1}{\mu}F(Tu_n),\;n{\geq}0$. for solving the general variational inequalities. The sequence $\{x_n}\$ is shown to converge in norm to the solutions of the general variational inequality GVI(F, g, C) under some mild conditions. Application to constrained generalized pseudo-inverse is included. Results proved in the paper can be viewed as an refinement and improvement of previously known results.

• Journal of Astronomy and Space Sciences
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• v.17 no.2
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• pp.151-162
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• 2000

The general properties of the NCBs, divided into A and F types according to their spectral types, have been presented. The evolutionary status of the F type near-contact binaries are closer to that of the contact systems, i.e., W UMa type binaries, if it is assumed that the evolution of the NCBs is governed by the thermal relaxation oscillation theory. The mass-radius relation, mass-luminosity relation and H-R diagram of the NCBs provide that the A type NCBs suffer from more active mass transfer than F types. The components of the NCBs ar still in main-sequence like W UMa type stars and their two components lines parallel to the ZAMS.

• Kyungpook Mathematical Journal
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• v.53 no.1
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• pp.135-141
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• 2013

In this paper we show that a $g$-frame for a Hilbert space $\mathcal{H}$ can be written as a linear combination of two $g$-orthonormal bases for $\mathcal{H}$ if and only if it is a $g$-Riesz basis for $\mathcal{H}$. Also, we show that every $g$-frame for a Hilbert space $\mathcal{H}$ is a multiple of a sum of three $g$-orthonormal bases for $\mathcal{H}$.

• Journal of Astronomy and Space Sciences
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• v.10 no.1
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• pp.36-43
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• 1993

We have made UBV light curves of a newly discovered eclipsing binary, SAO23229 at Sobaeksan Astronomy Observatory. We determined a minimum light time of HJD2448636.1170$pm$0.0005 that is 3 minimum later than predicted time, and found a peculiar light variation at phase 0.75 that may not be secondary eclipse. Orbital period of SAO23229 would be 4.2 days rather than 2.1 days. Our analysis of the light curves shows that SAO23229 has a detached configuration consisting of two almost identical F type main sequence stars.

• Bulletin of the Korean Space Science Society
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• 2009.10a
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• pp.35.1-35.1
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• 2009

We have established a database of galaxy spectral line strengths for the SDSS database using an improved line measuring method. Our work includes the entire SDSS DR7 galaxies within redshift of 0.2. The absorption line strengths measured by the SDSS pipeline are seriously contaminated by emission filling. Our code, GANDALF (gas and absorption line fitting code) performs more accurate measurements by effectively separating emission lines from absorption lines. A significant improvement has also been made on the velocity dispersion measurement, more notably in late-type galaxies. We have also identified a number of broad line region galaxies which were misclassified as normal galaxies by the SDSS pipeline. We developed an effective method measuring their line strengths. The database will be provided with new parameters that are indicative of the line strength measurement quality. In addition, we made galaxy templates for the Hubble sequence. The database will be useful for many fields of galaxy studies including star formation and AGN activities.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.3 no.1
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• pp.87-92
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• 2003

This paper describes a system for tracking multiple faces in an input video sequence using facial convex hull based facial segmentation and robust hausdorff distance. The algorithm adapts skin color reference map in YCbCr color space and hair color reference map in RGB color space for classifying face region. Then, we obtain an initial face model with preprocessing and convex hull. For tracking, this algorithm computes displacement of the point set between frames using a robust hausdorff distance and the best possible displacement is selected. Finally, the initial face model is updated using the displacement. We provide an example to illustrate the proposed tracking algorithm, which efficiently tracks rotating and zooming faces as well as existing multiple faces in video sequences obtained from CCD camera.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.65.2-65.2
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• 2013

A presence of a penumbra is one of the main properties of a mature sunspot, and its formation mechanism has been elusive due to a lack of observations that fully cover the formation process. Utilizing the New Solar Telescope at the Big Bear Solar Observatory, we observed the formation of a partial penumbra for about 7 hours simultaneously at the photospheric (TiO; $7057{\AA}$) and the chromospheric ($H{\alpha}$, $-1{\AA}$) spectral lines with high spatial and temporal resolution. From this uninterrupted, long observational sequence, we found that flux emergence under the stable chromospheric canopy fields resulted in penumbra formation, while emerging flux under the expanding chromospheric fields appeared as transient elongated granules. Based on these findings, we suggest a possible scenario for penumbra formation in which a penumbra forms when the emerging flux is constrained from continuing to emerge, but rather is trapped at the photospheric level by the overlying chromospheric canopy fields.

• East Asian mathematical journal
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• v.27 no.3
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• pp.319-337
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• 2011

We approximate a locally unique solution of a nonlinear equation in a Banach space setting using an inexact two-step Newton-type method. It turn out that under our new idea of recurrent functions, our semilocal analysis provides tighter error bounds than before, and in many interesting cases, weaker sufficient convergence conditions. Applications including the solution of nonlinear Chandrasekhar-type integral equations appearing in radiative transfer and two point boundary value problems are also provided in this study.

• International Journal of Aeronautical and Space Sciences
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• v.13 no.1
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• pp.99-105
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• 2012

Track-before-detect techniques based on dynamic programming have provided solutions for detecting targets from a sequence of images. In its application to airborne threat detection, dynamic programming solutions should take into account the distinguishable properties of objects in a collision course. This paper describes the development of a new track scoring function that accumulates scores for airborne targets in Bayesian framework. Numerical results show that the proposed scoring function has slightly better detection capabilities.

• The Pure and Applied Mathematics
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• v.15 no.4
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• pp.365-375
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• 2008

We present a new theorem for the semilocal convergence of Newton's method to a locally unique solution of an equation in a Banach space setting. Under a gamma-type condition we show that we can extend the applicability of Newton's method given in [12]. We also provide a comparative study between results using the classical Newton-Kantorovich conditions ([6], [7], [10]), and the ones using the gamma-type conditions ([12], [13]). Numerical examples are also provided.