• Geophysics and Geophysical Exploration
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• v.8 no.2
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• pp.170-176
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• 2005

Recently the velocity stack inversion is having many attentions as an useful way to perform various seismic data processing. In order to be used in various seismic data processing, the inversion method used should have properties such as robustness to noise and parsimony of the velocity stack result. The IRLS (Iteratively Reweighted Least-Squares) method that minimizes ${L_1}-norm$ is the one used mostly. This paper introduce another method, CGG (Conjugate Guided Gradient) method, which can be used to achieve the same goal as the IRLS method does. The CGG method is a modified CG (Conjugate Gradient) method that minimizes ${L_1}-norm$. This paper explains the CGG method and compares the result of it with the one of IRSL methods. Testing on synthetic and real data demonstrates that CGG method can be used as an inversion method f3r minimizing various residual/model norms like IRLS methods.

• Honam Mathematical Journal
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• v.31 no.3
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• pp.381-398
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• 2009

Let $G\;=\;O(k){\times}O(k){\times}O(q)$ and let $M^n$ be a closed G-invariant minimal hypersurface with constant scalar curvature in $S^{n+1}$. Then we obtain a theorem: If $M^n$ has 2 distinct principal curvatures at some point p, then the square norm of the second fundamental form of $M^n$, S = n.

• Bulletin of the Korean Mathematical Society
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• v.53 no.1
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• pp.247-262
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• 2016

We propose and analyze spectral and pseudo-spectral Jacobi-Galerkin approaches for weakly singular Volterra integral equations (VIEs). We provide a rigorous error analysis for spectral and pseudo-spectral Jacobi-Galerkin methods, which show that the errors of the approximate solution decay exponentially in $L^{\infty}$ norm and weighted $L^2$-norm. The numerical examples are given to illustrate the theoretical results.

• Journal of applied mathematics & informatics
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• v.9 no.1
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• pp.311-320
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• 2002

For second order linear elliptic problems over smooth domains, it is well known that the rate of convergence of the error in the $L_2$norm is one order higher than that in the $H^1$norm. For polygonal domains with reentrant corners, it has been shown in [15] that this extra order cannot be fully recovered when the h-version is used. We present theoretical and computational examples showing the sharpness of our results.

• Korean Journal of Remote Sensing
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• v.33 no.5_1
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• pp.455-467
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• 2017

When performing target detection using hyperspectral imagery, a feature extraction process is necessary to solve the problem of redundancy of adjacent spectral bands and the problem of a large amount of calculation due to high dimensional data. This study proposes a new band selection method using the $L_{2,1}$-norm regression model to apply the feature selection technique in the machine learning field to the hyperspectral band selection. In order to analyze the performance of the proposed band selection technique, we collected the hyperspectral imagery and these were used to analyze the performance of target detection with band selection. The Adaptive Cosine Estimator (ACE) detection performance is maintained or improved when the number of bands is reduced from 164 to about 30 to 40 bands in the 350 nm to 2500 nm wavelength band. Experimental results show that the proposed band selection technique extracts bands that are effective for detection in hyperspectral images and can reduce the size of the data without reducing the performance, which can help improve the processing speed of real-time target detection system in the future.

• Journal of applied mathematics & informatics
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• v.26 no.3_4
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• pp.583-590
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• 2008

In this article, we focuss on. sequences of polynomials with {$\pm1$} coefficients constructed by recursive argument that is known as Rudin-Shapiro polynomials. The asymptotic behavior of these polynomials defines as the ratio of their 2q-norm with 2-norm to be dominated by some number depending on q or "the best" by an absolute constant. In this work we first show the conjecture holds for some finite numbers of m and then introduce a technique that give the result for any positive odd integer m whenever it holds for all pervious even numbers.

• Journal of the Korean Mathematical Society
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• v.38 no.2
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• pp.337-348
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• 2001

The unitary Lie-Trotter-Kato product formula gives in a simplest way a meaning to the Feynman path integral for the Schroding-er equation. In this note we want to survey some of recent results on the norm convergence of the selfadjoint Lie-Trotter Kato product formula for the Schrodinger operator -1/2Δ + V(x) and for the sum of two selfadjoint operators A and B. As one of the applications, a remark is mentioned about an approximation therewith to the fundamental solution for the imaginary-time Schrodinger equation.

• Journal of Korean Academy of Nursing
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• v.45 no.6
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• pp.802-811
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• 2015

Purpose: The purpose of this study was to test and validate a model to predict living and brain death organ donation intention in nursing students. The conceptual model was based on the theory planned behavior. Methods: Quota sampling methodology was used to recruit 921 nursing students from all over the country and data collection was done from October 1 to December 20, 2013. Results: The model fit indices for the hypothetical model were suitable for the recommended level. Knowledge, attitude, subjective norm and perceived behavioral control explained 40.2% and 40.1% respectively for both living and brain death organ donation intention. Subjective norm was the most direct influential factor for organ donation intention. Knowledge had significant direct effect on attitude and indirect effect on subjective norm and perceived behavioral control. These effects were higher in brain death organ donation intention than in living donation intention. Conclusion: The overall findings of this study suggest the need to develop systematic education programs to increases knowledge about brain death organ donation. The development, application, and evaluation of intervention programs are required to improve subjective norm.

• Journal of East-West Nursing Research
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• v.28 no.1
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• pp.41-48
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• 2022

Purpose: The purpose of this study was to identify factors influencing prevention behaviors for particulate matter exposure in young adults. Methods: A convenience sample of 330 young adults was recruited from the community. Data were collected using a structured questionnaire and analyzed by descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients, and stepwise multiple regression analysis with the SPSS/WIN 26.0 program. Results: The factors affecting prevention behaviors of particulate matter exposure were self-efficacy (β=.54 p<.001), subjective norm (β=.18, p<.001) and using the air purifier (β=.-17, p<.001). These variables had a 46% variance to explain prevention behaviors for particulate matter exposure. Conclusion: Findings showed that 'self-efficacy' and 'subjective norm' were important factors influencing prevention behaviors of particulate matter exposure in young adults. Thus, we need to consider the positive impact of prevention behaviors of particulate matter exposure and increase the chances of prevention behaviors of particulate matter exposure program for young adults.

• Journal of the Korean Home Economics Association
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• v.36 no.7
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• pp.39-56
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• 1998

This paper concerned with the Honsu(婚需) norms of urban residents in Korea, and was designed to suggest a solution to solve the current problems of the extravagant Honsu with the changes int he customs related to Honsu. Data collected through interviews with questionaire were analyzed statistically by X2-test, ANOVA, Scheffe-test, factor analysis, cluster analysis and product moment correlation coefficients using SPSS PC+ program. Factors of HONSU norm, was characterized into 3 types, exchangabilities and focusing on groom's family, preparation of goods for housekeeping, and independence from parents and individualism. HONSU was found to be regarded as the basis for better life for the new family provided by their patents in terms of the family norm. The current problems of extravagant HONSU seems due to the family norm. Factors of HONSU norms could be grouped into 4 categories by the cluster analysis. They are 1)the preparation of basic house-keeping items for independent family, 2)an opportunity to secure an economic base for the new family, 3)an opportunity to show off their wealth by selecting easily exchangable goods, and 4)others who select items based on their personalities. An oppportunity to show off their wealth by selecting easily exchangable was the cultural norm of Honsu, and it was found that urban housewives had almost uniform thoughts about Honsu. Consideration of items for individuals' needs and independent life took place in deciding on Honsu for all four types of couples although the weight given to this consideration showed difference. Preparation for the new family and individual needs were the common grounds of HONSU norms in all categories through the weight was different.