• Journal of the Korean Solar Energy Society
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• v.28 no.4
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• pp.68-75
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• 2008

The purpose of this research is revise the value yield to compensate of measure the difference between computer simulation and the measurement value on the two methods which can calculates thermal performance. The way is need to understand about thermal performance, air tightness, simulations and comparisons of analysis to influence the value of each identified. The opening type of the windows and doors to be used at the analysis are T/T, L/S and SL Different condition of the windows and doors excluded except the opening type. Each of the four samples was selected by the way of opening. Result of the analysis of the difference between measurement and simulation are that T/T approach 5.3%, L/S approach 15.7%, SL approach 21% and the more air-tightness guarantees less difference of the numerical value. Each compensation value calculates by the correlation regression analysis and the air-tightness data. After the compensation of the resulting difference in T/T, L/S, SL indicate 5.4%, 2.5%, 1.0% respectively.

• Journal of applied mathematics & informatics
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• v.35 no.5_6
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• pp.551-563
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• 2017

In this paper, by using fixed point theorems in cones, the existence of positive solutions is considered for nonlinear m-point boundary value problem for the following second-order dynamic equations on time scales $$u^{{\Delta}{\nabla}}(t)+a(t)f(t,u(t))=0,\;t{\in}(0,T),\;{\beta}u(0)-{\gamma}u^{\Delta}(0)=0,\;u(T)={\sum_{i=1}^{m-2}}\;a_iu({\xi}_i),\;m{\geq}3$$, where $a(t){\in}C_{ld}((0,T),\;[0,+{\infty}))$, $f{\in}C([0,T]{\times}[0,+{\infty}),\;(-{\infty},+{\infty}))$, the nonlinear term f is allowed to change sign. We obtain several existence theorems of positive solutions for the above boundary value problems. In particular, our criteria generalize and improve some known results [15] and the obtained conditions are different from related literature [14]. As an application, an example to demonstrate our results is given.

• Korean Journal of Radiology
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• v.22 no.8
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• pp.1352-1368
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• 2021

Objective: For an accurate dynamic contrast-enhanced (DCE) MRI analysis, exact baseline T1 mapping is critical. The purpose of this study was to compare the pharmacokinetic parameters of DCE MRI using synthetic MRI with those using fixed baseline T1 values. Materials and Methods: This retrospective study included 102 patients who underwent both DCE and synthetic brain MRI. Two methods were set for the baseline T1: one using the fixed value and the other using the T1 map from synthetic MRI. The volume transfer constant (K^trans), volume of the vascular plasma space (v_p), and the volume of the extravascular extracellular space (v_e) were compared between the two methods. The interclass correlation coefficients and the Bland-Altman method were used to assess the reliability. Results: In normal-appearing frontal white matter (WM), the mean values of K^trans, v_e, and v_p were significantly higher in the fixed value method than in the T1 map method. In the normal-appearing occipital WM, the mean values of v_e and v_p were significantly higher in the fixed value method. In the putamen and head of the caudate nucleus, the mean values of K^trans, v_e, and v_p were significantly lower in the fixed value method. In addition, the T1 map method showed comparable interobserver agreements with the fixed baseline T1 value method. Conclusion: The T1 map method using synthetic MRI may be useful for reflecting individual differences and reliable measurements in clinical applications of DCE MRI.

• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.229-244
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• 2005

In this paper, we study the third order ordinary differential equation : $$x'(t)=f(t,x(t),x'(t),x'(t)),t{\in}(0,1)$$ subject to the boundary value conditions: $$x'(0)=x'(\xi),x'(1)=^{m-3}{\Sigma}_{i=1}{{\beta}x'({\eta}i),x'(1)=0}$$. Here ${\beta}_{i}{\in}R,\;^{m-3}{\Sigma}_{i=1}\;{\beta}_{i}\;=\;1,\;0<{\eta}_1<{\eta}_2<{\cdots}<{\eta}_{m-3}<1,\;0<\xi<1$. This is the case dimKer L = 2. When the ${\beta}_i$ have different signs, we prove some existence results for the m-point boundary value problem at resonance by use of the coincidence degree theory of Mawhin [12, 13]. Since all the existence results obtained in previous papers are for the case dimKerL = 1, our work is new.

• Journal of applied mathematics & informatics
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• v.28 no.3_4
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• pp.763-772
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• 2010

This paper deals with the existence of triple positive solutions for the nonlinear second-order three-point boundary value problem z"(t)+a(t)f(t, z(t), z'(t))=0, t $\in$ (0, 1), $z(0)={\nu}z(1)\;{\geq}\;0$, $z'(\eta)=0$, where 0 < $\nu$ < 1, 0 < $\eta$ < 1 are constants. f : [0, 1] $\times$ [0, $+{\infty}$) $\times$ R $\rightarrow$ [0, $+{\infty}$) and a : (0, 1) $\rightarrow$ [0, $+{\infty}$) are continuous. First, Green's function for the associated linear boundary value problem is constructed, and then, by means of a fixed point theorem due to Avery and Peterson, sufficient conditions are obtained that guarantee the existence of triple positive solutions to the boundary value problem. The interesting point is that the nonlinear term f is involved with the first-order derivative explicitly.

• Management & Information Systems Review
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• v.36 no.1
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• pp.273-290
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• 2017

Internet of Things (IoT) is considered to be the next wave of Information Technology transformation after the Internet has changed the process of doing business. Since the domain of IoT ranging from the sensor technology to service to the users is wide, the structure of the research domain is not delineated clearly. To do that we suggest to use the Technology Stack Model proposed by Porter et al.(2014) to measure the maturity level of IoT in organizations. Based on the Stack Model, for the general understandings of IoT, we do keyword analyses on the academic papers whose major research issue is IoT. It is found that the current status of IoT application from the perspectives of cloud and big data analytics is not active, meaning that the real value of IoT has not been realized. We also examine the cases which deal with the part of cloud process which is crucial for value accrual. Based on these findings, we suggest the future direction of IoT research. We also propose that IT is to value chain what IoT is to the Stack Model to derive value in organizations.

• Journal of Korean Academy of Nursing
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• v.4 no.2
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• pp.144-158
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• 1974

This study was undertaken in an attempt to; 1) measure value orientation of nursing activities, 2) identify the relationship between nurse's role perception and patient's expectation, and 3) evaluate the pattern of nursing education and nursing service administration. 203 hospitalized adults and 203 professional nurses from 11 general hospitals in Seoul during the period of July to December 1973 were tested according to questionnaire based on 4 categories of clinical nursing activities, 1) physical care, 2) observation and control, 3) psycho-social care and 4) therapeutic measures. Results of the study are as follows: 1. Nurses were more concerned than patients in the physical care category. Significant difference was revealed by p<.01 level (t=2.800). Mean value score of nurses was average (2.84), and mean value score of patients was relative' y low (2.49). None of the physical care category questionnaire items were over 3.5. 2. Respondents from hospitals of total care system revealed significant difference in the physical care category by P〈.025 level. (t=2.242). Mean value score of both group were average level (nurse 2.90, patient 2.53), nurses showed higher concern. 3. Difference between nurse's role perception and patient's expectation in observation and control category was revealed non- significance by p〉0.05. level (t=1.238). Mean value score of both group revealed relatively high (nurse=3.44, patient 3.19). 4. Difference between nurse's role perception and patient〉expectation in psycho-social cart category revealed non- significance by p〉.05 level (t=0.758), Mean value score of both group revealed average level (nurse =2.71, patient =2.53), 5. Non- significant difference was noted between B. S. N. and diploma nurse's role perception in the psycho- social care category by p> 0.1 level (t=0.316). 4. Difference between nurse's role perception and patient's expectation in the rapeutic me assures category revealed non- significance by p〉0.05 level) t=0.503). Horses showed high concern by mean value score 3.56 level and patients relatively high by 3.41. All items of this category revealed very high or relatively high value score.

• Journal of applied mathematics & informatics
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• v.22 no.1_2
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• pp.295-306
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• 2006

In this paper, by using the Krasnoselskii fixed point theorem, we study the existence of 2m or 2m + 1 symmetric positive solutions of fourth-order two point boundary value problem y(4)(t) - f(t, y(t), y"(t))= 0, y(0) = y(1) = y'(0) = y"(1)=0.

• Journal of the Korean Mathematical Society
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• v.34 no.1
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• pp.247-255
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• 1997

In this paper, we are concerned with the existence of positive solutions for the boundary value problems of the form; $$(1) u"(t) + q(t)g(u(t)) = 0, 0 < t < 1 $$ $$ u(0) = 0 = u(1), $$ where q is singular at 0 and /or 1.or 1.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.1
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• pp.1-11
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• 2010

Generation and transportation of runoff and pollutant loads within watershed generated eutrophication at Daecheong reservoir. To improve water quality at Daecheong reservoir, the best management practices should be developed and applied at upper watersheds for water quality improvement at downstream areas. In this study, two small watersheds of upper Daecheong reservoir were selected. The Long-Term Hydrologic Impact Assessment (L-THIA) model has been widely used for the estimation of the direct runoff worldwide. To apply the L-THIA ArcView GIS model was evaluated for direct runoff and water quality estimation at small watershed. And the Web-based Hydrograph Analysis Tool (WHAT) was used for direct runoff separating from total flow. As a result, the $R^2$ (Coefficient of determination) value and Nash-Sutcliffe coefficient value for direct runoff comparison at An-nae watershed were 0.81 and 0.71, respectively. And the $R^2$ value and Nash-Sutcliffe coefficient value at Wol-oe were 0.95 and 0.93. The $R^2$ value of BOD, TOC, T-N and T-P at An-nae watershed were BOD 0.94, TOC 0.81, T-N 0.94 and T-P 0.89. And the $R^2$ value of BOD, TOC, T-N and T-P at Wol-oe watershed were BOD 0.80, TOC 0.93, T-N 0.86 and T-P 0.65. The result that estimated pollutant loadings using the L-THIA ArcView GIS model reflected well the measured pollutant loadings except for T-P in Wol-oe watershed. With L-THIA ArcView GIS model, the direct runoff and non-point pollutant (NPS) loadings in the watershed could be analyzed through simple input data such as daily rainfall, land uses, and hydrologic soil group.