• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.65-65
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• 2002

In remote sensing, images are acquired over the same area by sensors of different spectral ranges (from the visible to the microwave) and/or with different number, position, and width of spectral bands. These images are generally partially redundant, as they represent the same scene, and partially complementary. For many applications of image classification, the information provided by a single sensor is often incomplete or imprecise resulting in misclassification. Fusion with redundant data can draw more consistent inferences for the interpretation of the scene, and can then improve classification accuracy. The common approach to the classification of multisensor data as a data fusion scheme at pixel level is to concatenate the data into one vector as if they were measurements from a single sensor. The multiband data acquired by a single multispectral sensor or by two or more different sensors are not completely independent, and a certain degree of informative overlap may exist between the observation spaces of the different bands. This dependence may make the data less informative and should be properly modeled in the analysis so that its effect can be eliminated. For modeling and eliminating the effect of such dependence, this study employs a strategy using self and conditional information variation measures. The self information variation reflects the self certainty of the individual bands, while the conditional information variation reflects the degree of dependence of the different bands. One data set might be very less reliable than others in the analysis and even exacerbate the classification results. The unreliable data set should be excluded in the analysis. To account for this, the self information variation is utilized to measure the degrees of reliability. The team of positively dependent bands can gather more information jointly than the team of independent ones. But, when bands are negatively dependent, the combined analysis of these bands may give worse information. Using the conditional information variation measure, the multiband data are split into two or more subsets according the dependence between the bands. Each subsets are classified separately, and a data fusion scheme at decision level is applied to integrate the individual classification results. In this study. a two-level algorithm using hierarchical clustering procedure is used for unsupervised image classification. Hierarchical clustering algorithm is based on similarity measures between all pairs of candidates being considered for merging. In the first level, the image is partitioned as any number of regions which are sets of spatially contiguous pixels so that no union of adjacent regions is statistically uniform. The regions resulted from the low level are clustered into a parsimonious number of groups according to their statistical characteristics. The algorithm has been applied to satellite multispectral data and airbone SAR data.

• Korean Chemical Engineering Research
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• v.55 no.3
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• pp.409-418
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• 2017

In preparation of self-repairing polymer-modified waterproofing asphalt-montmorillonite (MMT) composite, silylation-modification characteristics of cation ($Na^+$) exchanged K-10 (Na-MMT-K) using 3-aminopropyltriethoxysilane (APS) were studied and the optimal conditions of its silylation-modification process were proposed by use of the results of instrumental analysis, including FTIR, XRD, NMR and TGA, on silylation-modified Na-MMT-K (S-Na-MMT-K) under various conditions. According to FTIR analysis on S-Na-MMT-K, its peak-strengths of Si-O, -$NH_2$, -$CH_2$- and -OH, correlated with APS silylation-modification reaction, were compared each other. As a result, its optimal conditions including APS-MMT reacting period, APS-stirring period prior to APS-MMT reaction, APS concentration and reaction temperature were turned out to be 2~3 h, 20 min, 7.5 w/v% and $50^{\circ}C$, respectively. In addition, the optimal conditions induced from the results of TGA were also nearly consistent to those according to the results of FTIR analyses. These optimal conditions were turned out to be almost consistent to those drawn according to a criterion from XRD results suggested previously by Lee et al., by which the criterion was validated.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.4
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• pp.466-473
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• 2013

In this paper, a compact planar multi-loop self-resonant coil of high quality factor with a coaxial cross section is proposed for effective wireless charging. The proposed coil has high Q-factor and a resonant frequency of a coil can be easily controlled by adjusting distributed capacitance. For designing the coil, a self-inductance and a distributed capacitance are calculated theoretically. The self-inductance is calculated from the sum of the mutual energies between small circular loops that are made by dividing the cross section of the coil. To verify its properties and calculation results, the self-resonant coils are fabricated by using a coaxial cable with characteristic impedance of $50{\Omega}$. The measured frequencies are very consistent with the calculated ones. In addition, the resonant frequency can be adjusted slightly by the tuning parameter ${\gamma}$. The resonant coils are applied to a tablet PC, the Q-factors of the Tx and Rx resonant coils are 282 and 135, respectively. As a result of measurement when height between the two resonant coils is 4.4 cm, the power transfer efficiency is more than 80 % within a radius of 5 cm.

• Journal of the Korean Society of School Health
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• v.21 no.2
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• pp.1-11
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• 2008

Purpose: Few studies have attempted to explain the childhood's sociality issue in Korea. This study was conducted to investigate the association between obesity stress and sociality factors. Methods : The study subjects were 4th, 5th, and 6th grade students from the elementary schools in Kwangju, Anyang, and Hwasung city. The cross sectional study was carried out through the self-reported questionnaire survey about obesity stress, sociality, and socio-demographic characteristics. The data was analyzed by multiple regression analysis using SPSS 12.0 version. Results : Overall, the findings of this study were consistent with previous studies. The measures of obesity stress showed significant negative relationships with measures of childhood sociality. Specifically, the association between mental stress from obesity and socialization was more higher than other variables. In addition, multiple regression analysis found that the effect of mental stress from obesity on childhood sociality was more higher than the effect of stress from physical discomfort and the effort to overcome the obesity stress. Conclusion : Findings provide evidence for the notion that the measures of obesity stress is significantly associated with childhood sociality.

• Research in Community and Public Health Nursing
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• v.19 no.2
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• pp.247-259
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• 2008

Purpose: This study was conducted to develop a teacher-efficacy scale which is adequate for heath education teachers. Method: A preliminary questionnaire was made based on the hypothetical factors. A total of 364 health education teachers answered to the preliminary test, and the potential factors of teacher-efficacy were checked out by exploratory factor analysis (EFA). In the main test 378 health education teachers answered, the factor structure was drawn by EFA, and confirmatory factor analysis (CFA) was conducted to test and the fitness of the factor model. Results: Through the preliminary test, 5 potential factors were found, which were instruction, health-service, administrative task, interpersonal relationship, and community connection. Also, 48 items were reduced to 31 items. Through the main test, from the 34 items were extracted 4 factors with 24 items, And then teacher-efficacy scale was developed, which included the subscales of instruction efficacy, health-service efficacy, task-interpersonal efficacy, and community connection efficacy. Conclusion: Different from that for other subject teachers, the factor structure for health teachers had 4 factors with 24 items. The scale developed in this study is consistent with health teachers' work areas, and for this reason, has significance as a adequate and valid scale to measure teacher-efficacy of health education teachers.

• Journal of Korean Academy of Nursing
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• v.36 no.2
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• pp.361-372
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• 2006

Purpose: This paper was conducted to examine the effects of transformational leadership behaviors, within the substitutes for leadership model(Kerr & Jermier, 1978). Method: Data was collected from 181 staff nurses in 3 general hospitals, with self-reporting questionnaires(MLQ developed by Bass, rd-SLS developed by Podsakoff, et at., and MSQ developed by Weiss, et al.). Descriptive statistics, factor analysis, Cronbach's alpha and moderated regression analysis were used. Result: 1) The transformational leader behaviors and substitutes for leadership each had correlations with job satisfaction. 2) The total amount of variance accounted for by the substitutes for leadership was substantially greater than by the transformational leadership behaviors. 3) Few of the substitutes variables moderated the relationships between the transformational leader behaviors and job satisfaction in a manner consistent with that specified by Howell, Dorfman, and Kerr(1986). Conclusion: The finding of this study suggest that leaders need to have a better understanding of those contextual variables that influence job satisfaction. Thus future research should focus attention on the moderating effects of substitutes, as well as the things that leaders can do to influence them. In addition, it may be good to examine the effects of substitutes on other criterion variables.

• Korean Journal of Adult Nursing
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• v.28 no.2
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• pp.226-236
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• 2016

Purpose: The aim of this study was to evaluate the nutritional status and to identify factors affecting malnutrition in hemodialysis patients. Methods: Data were collected from a convenience sample of 125 hemodialysis patients who agreed to participate in the study, between August 1 and October 4, 2014. Five structured questionnaires were used: Patient-generated Subjective Global Assessment, Simplified Nutritional Appetite Questionnaire, Self-rating Depression Scale, Fatigue Scale, and Family Support Scale. Data were analyzed by descriptive statistics, t-test, Mann-Whitney U test, ${\chi}^2$-test, and stepwise multiple regression analysis by using SPSS/WIN 22.0 program. Results: Of 125 patients, 30.4% were found to be malnourished. Malnutrition was related to age, family household income, depression, fatigue, social support, appetite, and levels of C-reactive protein and serum albumin. Stepwise multiple regression analysis showed that appetite, C-reactive protein level, fatigue, and albumin level were significant factors affecting malnutrition in hemodialysis patients. Conclusion: Regular and consistent nutritional assessment is essential in hemodialysis patients. Nurses who care for hemodialysis patients need to consider the factors identified from these findings when assessing their patients' nutritional status and needs.

• Particle and aerosol research
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• v.5 no.3
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• pp.123-131
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• 2009

This paper presents simulation results of particle transport in low-pressure, low-temperature plasma environment. The size dependent transport of particles in the plasma is investigated with a two-dimensional simulation tool developed in-house for plasma chamber analysis and design. The plasma model consists of the first two and three moments of the Boltzmann equation for ion and electron fluids respectively, coupled to Poisson's equation for the self-consistent electric field. The particle transport model takes into account all important factors, such as gravitational, electrostatic, ion drag, neutral drag and Brownian forces, affecting the motion of particles in the plasma environment. The particle transport model coupled with both neutral fluid and plasma models is simulated through a Lagrangian approach tracking the individual trajectory of each particle by taking a force balance on the particle. The size dependant trap locations of particles ranging from a few nm to a few ${\mu}m$ are identified in both electropositive and electronegative plasmas. The simulation results show that particles are trapped at locations where the forces acting on them balance. While fine particles tend to be trapped in the bulk, large particles accumulate near bottom sheath boundaries and around material interfaces, such as wafer and electrode edges where a sudden change in electric field occurs. Overall, small particles form a "dome" shape around the center of the plasma reactor and are also trapped in a "ring" near the radial sheath boundaries, while larger particles accumulate only in the "ring". These simulation results are qualitatively in good agreement with experimental observation.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.7
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• pp.51-57
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• 1995

The theoretical analysis for AlInAs/GaInAs resonant tunneling diodes (RTDs), which have shown the improved negative differential resistance (NDR) characteristics, has scarcely been made in comparison with AlGaAS/GaAs RTDs. In this paper, the static current-voltage relation of Al$_{0.48}In_{0.52}As/Ga_{0.47}In_{0.53}$As RTDs were numerically estimated by using a self-consistent method. Assuming a simplified RTD with single quantum well structure and spacer layers, the peak current density (J$_{P}$) and the peak-to-valley current ratio (PVCR) were analysed as the function of the thickness of the well, the barrier and the spacer layer, and temperature. As the results, the peak current density and the peak-to-valley current ratio indicated a reciprocal relation roughly in respect to the thicknesses of the well and the barrier, and it was theoretically predicted that it be not attainable to provide a high peak current desity (J$_{P}$) over 1${\times}10^{5}A/cm^{2}$ as well as the large peak-to-valley current ratio (PVCR) over 10 that were the the critical conditions for the practical use.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.59.2-59.2
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• 2013

Wilson and Bappu found a tight correlation between the stellar absolute visual magnitude (MV) and the width of the Ca II K emission line for late-type stars in 1957. Here, we revisit the Wilson-Bappu relationship (hereafter, WBR) to claim that WBR can be an excellent indicator of stellar surface gravity of late-type stars as well as a distance indicator. We have measured the width (W) of the Ca II K emission line in high resolution spectra of 125 late-type stars, which were obtained with Bohyunsan Optical Echelle Spectrograph (BOES) and adopted from the UVES archive. Based on our measurement of the emission line width (W), we have obtained a WBR of $M_V=33.76-18.00{\log}W$. In order to extend the WBR to be a surface gravity indicator, the stellar atmospheric parameters such as effective temperature ($T_{eff}$), surface gravity (logg), metallicity ([Fe/H]), and micro-turbulence (${\xi}_{tur}$) have been derived from the self-consistent detailed analysis using the Kurucz stellar atmospheric model and the abundance analysis code, MOOG. Using these stellar parameters and logW, we found that ${\log}g=-5.85\;{\log}W+9.97\;{\log}T_{eff}-23.48$ for late-type stars.