• 컴퓨터교육학회논문지
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• 제16권3호
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• pp.1-12
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• 2013

본 연구는 모바일자기효능감, 주관적규범이 지각된 유용성과 지각된 이용용이성에 영향을 주어 궁극적으로 모바일웹서비스 수용의도에 영향을 미치는지를 기술수용모형(Technology Acceptance Model, TAM)을 통하여 알아보는 것을 목적으로 수행되었다. 이를 위해 2011학년도 2학기 A사이버대학교의 모바일웹서비스가 제공되는 과목에 등록한 144명의 학생을 대상으로 2011년 가을학기 강의 종료 전 2주 동안 웹 설문조사를 실시하였다. 본 연구의 결과는 첫째, 모바일자기효능감(${\beta}$=.43, p<.05), 주관적규범(${\beta}$=.30, p<.05), 지각된 이용용이성(${\beta}$=.25, p<.05)은 지각된 유용성에 영향을 주었고 둘째, 모바일자기효능감(${\beta}$=.36, p<.05), 주관적규범(${\beta}$=.44, p<.05)은 지각된 이용용이성에 영향을 미쳤다. 셋째, 지각된 유용성(${\beta}$=.94, p<.05)은 모바일웹서비스 수용의도에 영향을 미침을 확인하였으나 지각된 이용용이성은 모바일웹서비스 수용의도에 유의한 영향을 주지 못하였다. 본 연구는 최근 급부상하고 있는 사이버대학교 모바일웹서비스의 좀 더 나은 설계와 운영을 위한 시사점을 제공한다.

• 대한수학회지
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• 제58권3호
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• pp.553-569
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• 2021

In this paper, we present and analyze a fully discrete numerical method for solving the time-fractional diffusion wave equation: ∂^β_tu - div(a∇u) = f, 1 < β < 2. We first construct a difference formula to approximate ∂^β_tu by using an interpolation of derivative type. The truncation error of this formula is of O(△t^2+δ-β)-order if function u(t) ∈ C^2,δ[0, T] where 0 ≤ δ ≤ 1 is the Hölder continuity index. This error order can come up to O(△t^3-β) if u(t) ∈ C³ [0, T]. Then, in combinination with the linear finite volume discretization on spatial domain, we give a fully discrete scheme for the fractional wave equation. We prove that the fully discrete scheme is unconditionally stable and the discrete solution admits the optimal error estimates in the H¹-norm and L₂-norm, respectively. Numerical examples are provided to verify the effectiveness of the proposed numerical method.

• Journal of applied mathematics & informatics
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• 제28권1_2호
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• pp.487-498
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• 2010

For some $\phi$-sequences $\phi_1$, $\phi_2$ and $\phi_3$, and $\kappa$-function $\kappa_1$, $\kappa_2$ and $\kappa_3$ with $\kappa_1^{-1}(x)\kappa_2^{-1}(x)\;{\geq}\;\kappa_3^{-1}(x)$ for $x\;{\geq}\;0$, the Luxemburg norm is lower semi-continuous on ${\kappa}{\phi}BV_0$, and some specialized equivalent conditions are considered.

• 대한간호학회지
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• 제33권3호
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• pp.365-375
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• 2003

Purpose: This study was aimed to investigate the health related quality of life and related factors of organ transplant recipients. Method: The participants were 188 people who had liver(86), kidney(81), or heart(24) transplanted. Data on the demographic characteristics, transplantation-related characteristics, symptom frequency or discomfort measured by Transplant Symptom Frequency and Symptom Distress Scale by Lough et al(l987), and health related quality of life measured by SF-36(version 2) were collected. Result: Overall health related quality of life score was 492.1 for 100scoring and, 344.9 for norm based. Physical functioning showed the highest quality of life score (77.5) and vitality showed the lowest(51.l). The kidney transplanted showed the highest quality of life (504.4) and the heart transplanted showed the lowest(426.7) Quality of life was related with occupation(p=.016) and symtom discomfort(p < .0001). Conclusion: The health related quality of life of transplated patients was lower than the norm of American. Further studies need to be done to identify the norm of Korean and to investigate the effect of releving symptom discomfort on the increasing the health related quality of life.

• 대한수학회지
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• 제51권1호
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• pp.203-224
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• 2014

We propose and analyze a spectral Jacobi-collocation approximation for fractional order integro-differential equations of Fredholm-Volterra type. The fractional derivative is described in the Caputo sense. We provide a rigorous error analysis for the collection method, which shows 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.

• 통합자연과학논문집
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• 제11권3호
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• pp.154-160
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• 2018

Consider the problem of estimating a $p{\times}1$ mean vector ${\theta}(p-r{\geq}3)$, r = rank(K) with a projection matrix K under the quadratic loss, based on a sample $Y_1$, $Y_2$, ${\cdots}$, $Y_n$. In this paper a James-Stein type estimator with shrinkage form is given when it's variance distribution is specified and when the norm ${\parallel}{\theta}-K{\theta}{\parallel}$ is constrain, where K is an idempotent and symmetric matrix and rank(K) = r. It is characterized a minimal complete class of James-Stein type estimators in this case. And the subclass of James-Stein type estimators that dominate the sample mean is derived.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제6권2호
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• pp.9-24
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• 2002

Total Variation(TV) regularization method is effective for reconstructing "blocky", discontinuous images from contaminated image with noise. But TV is represented by highly nonlinear integro-differential equation that is hard to solve. There have been much effort to obtain stable and fast methods. C. Vogel introduced "the Fixed Point Lagged Diffusivity Iteration", which solves the nonlinear equation by linearizing. In this paper, we apply multigrid(MG) method for cell centered finite difference (CCFD) to solve system arise at each step of this fixed point iteration. In numerical simulation, we test various images varying noises and regularization parameter $\alpha$ and smoothness $\beta$ which appear in TV method. Numerical tests show that the parameter ${\beta}$ does not affect the solution if it is sufficiently small. We compute optimal $\alpha$ that minimizes the error with respect to $L^2$ norm and $H^1$ norm and compare reconstructed images.

• Kyungpook Mathematical Journal
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• 제53권2호
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• pp.295-306
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• 2013

First we present the explicit formula for the norm of a symmetric bilinear form on the 2-dimensional real predual of the Lorentz sequence space $d_*(1,w)^2$. Using this formula, we classify the extreme points of the unit ball of $\mathcal{L}_s(^2d_*(1,w)^2)$.

• 전기전자학회논문지
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• 제20권2호
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• pp.152-162
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• 2016

전기 저항률 단층촬영법(ERT)은 표면 전극으로부터 측정된 전압을 사용하여 물체 내부의 임피던스 분포를 영상화하는 기술이다. ERT 역문제는 비정치성(ill-posedness)이 매우 심하여 영상복원의 수렴성을 확보하기 위해 조정방법이 사용된다. 사용된 조정방법에 따라 영상복원 성능이 달라지므로 상황에 따라 보다 강건한 영상 복원 성능을 얻기 위해, 서로 다른 영상복원 특성을 나타내는 L1-norm 조정방법과 Total Variation (TV) 조정방법의 두 개의 모드가 상호작용하는 상호작용 이중-모드 조정방법을 제안하였다. 제안한 이중-모드 조정방법은 실제 상황에 따라 달라지는 모드 확률을 계산하고 이에 근거하여 적합한 모드를 선택하거나 두 개의 모드를 결합한다. 모의실험을 수행하여 제안된 기법의 영상 복원 성능을 평가한 결과 비교적 양호한 성능을 나타내었다.

• Fisheries and Aquatic Sciences
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• 제19권4호
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• pp.21.1-21.11
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• 2016

Background: The evaluation of suitable reference genes as normalization controls is a prerequisite requirement for launching quantitative reverse transcription-PCR (RT-qPCR)-based expression study. In order to select the stable reference genes in abalone Haliotis discus hannai tissues (gill and hepatopancreas) under heavy metal exposure conditions (Cu, Zn, and Cd), 12 potential candidate housekeeping genes were subjected to expression stability based on the comprehensive ranking while integrating four different statistical algorithms (geNorm, NormFinder, BestKeeper, and ${\Delta}CT$ method). Results: Expression stability in the gill subset was determined as RPL7 > RPL8 > ACTB > RPL3 > PPIB > RPL7A > EF1A > RPL4 > GAPDH > RPL5 > UBE2 > B-TU. On the other hand, the ranking in the subset for hepatopancreas was RPL7 > RPL3 > RPL8 > ACTB > RPL4 > EF1A > RPL5 > RPL7A > B-TU > UBE2 > PPIB > GAPDH. The pairwise variation assessed by the geNorm program indicates that two reference genes could be sufficient for accurate normalization in both gill and hepatopancreas subsets. Overall, both gill and hepatopancreas subsets recommended ribosomal protein genes (particularly RPL7) as stable references, whereas traditional housekeepers such as ${\beta}-tubulin$ (B-TU) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were ranked as unstable genes. The validation of reference gene selection was confirmed with the quantitative assay of MT transcripts. Conclusions: The present analysis showed the importance of validating reference genes with multiple algorithmic approaches to select genes that are truly stable. Our results indicate that expression stability of a given reference gene could not always have consensus across tissue types. The data from this study could be a good guide for the future design of RT-qPCR studies with respect to metal regulation/detoxification and other related physiologies in this abalone species.