• Journal of the Mineralogical Society of Korea
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• v.17 no.3
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• pp.209-220
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• 2004

Adsorption behavior of Cu onto Hwangto, from Pankok-ri, Kosung-gun, suspension was studied using Cu batch adsorftion experiment and computer program MINTEQA2 and FITEQL 3.2. The sorption of copper was investigated as a function of pH, copper concentration and $NaNO_3$ background concentration (0.01 and 0.1 M). The concentration of copper was analyzed using ICP-AES. The sorption of copper onto Hwangto suspension increased with increasing pH and copper concentration. The adsorption percentage of copper drastically increased from pH 5.5 to 6.5, and reached nearly 100% at pH 7.5. Because the amount of copper solution and the ionic strength of background electrolyte may not affect the sorption of copper onto Hwangto, the copper ion may be combined at the surface of Hwangto as an inner-sphere complex. Using the MINTEQA2 program, the speciation of copper was calculated as a function of pH and copper concentration. The concentration of $Cu^{2+}$ decreased and that of $Cu(OH)_2$ increased with increasing pH. The uptake of copper in the Hwangto suspension was simulated by FITEQL3.2 program using two sites-three pKas model, which is composed of silicate reaction site and Fe oxide reaction site. The copper absorption reaction constants were calculated in the case of 2～6 mL of copper solution. The Fe oxide reaction site rapidly adsorbs copper ion between pH 4.5～6.5. Silicate reaction site adsorbs little copper ion at low copper concentration but much at high copper concentration. The removal amount of copper by precipitation was negligible in comparison with that of adsorption. The Fe oxide reaction site may has higher adsorption affinity of copper ion than silicate reaction site.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.850-855
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• 2005

Model was developed to predict the growth of Listeria monocytogenes in raw pork. Experiment condition for model development was full 5-by-7 factorial arrangements of temperature (0, 5, 10, 15, and $20^{\circ}C$) and time (0, 1, 2, 3, 18, 48, and 120 hr). Gompertz values A, C, B, and M, and growth kinetics, exponential growth rate (EGR), generation time (GT), lag phase duration (LPD), and maximum population density (MPD) were calculated based on growth increased data. GT and LPD values gradually decreased, whereas EGR value gradually increased with increasing temperature. Response surface analysis (RSA) was carried out using Gompertz B and M values, to formulate equation with temperature being main control factor. This equation was applied to Gompertz equation. Experimental and predictive values for GT, LPD, and EGR, compared using the model, showed no significant differences (p<0.01). Proposed model could be used to predict growth of microorganisms for exposure assessment of MRA, thereby allowing more informed decision-making on potential regulatory actions of microorganisms in raw pork.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.194-198
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• 2005

Growth curves of Listeria monocytogenes in modified surimi-based imitation crab (MIC) broth were obtained by measuring cell concentration in MIC broth at different culture conditions [initial cell numbers, $1.0{\times}10^{2},\;1.0{\times}10^{3}\;and\;1.0{\times}10^{4}$, colony forming unit (CFU)/mL; temperature, 15, 20, 25, 37, and $40^{\circ}C$] and applied to Gompertz model to determine microbial growth indicators, maximum specific growth rate constant (k), lag time (LT), and generation time (GT). Maximum specific growth rate of L. monocytogenes increased rapidly with increasing temperature and reached maximum at $37^{\circ}C$, whereas LT and GT decreased with increasing temperature and reached minimum at $37^{\circ}C$. Initial cell number had no effect on k, LT, and GT (p > 0.05). Polynomial and square root models were developed to express combined effects of temperature and initial cell number using Gauss-Newton Algorism. Relative coefficients of experimental k and predicted k of polynomial and square root models were 0.92 and 0.95, respectively, based on response surface model. Results indicate L. monocytogenes growth was mainly affected by temperature and square root model was more effective than polynomial model for growth prediction.

• The Journal of the Acoustical Society of Korea
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• v.20 no.6
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• pp.94-103
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• 2001

The goal of using numerical methods in this study is two-fold: to replicate a set of measured, individualized HRTFs by a computer simulation, and also to visualise the resultant sound field around the head. Two methods can be wed: the Boundary Element Method (BEM) and the Infinite-Finite Element Method (IFEM). This paper presents the results of a preliminary study carried out on a KEMAR dummy-head, the geometry of which was captured with a high accuracy 3-D laser scanner and digitiser. The scanned computer model was converted to a few valid BEM and IFEM meshes with different polygon resolutions, enabling us to optimise the simulation for different frequency ranges. The results show a good agreement between simulations and measurements of the sound pressure at the blocked ear-canal of the dummy-head. The principle of reciprocity provides an effect method to simulate HRTF database. The BEM was also used to investigate the total sound field around the head, providing a tool to visualise the sound field for different arrangements of virtual acoustic imaging systems.

• Journal of the Korean Society of Radiology
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• v.12 no.5
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• pp.623-630
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• 2018

Non-alcoholic fatty liver disease is the most common cause of chronic liver diseases. This study was to characterize early hepatic lipid changes in fatty liver rat model by in vivo short-echo time(TE) $^1H$-MRS(Proton - Magnetic Resonance Spectroscopy). Each the examinations were measured from liver parenchyma in rats at 0, 2, 4, 6, 8 weeks followed by high fat diet, respectively. Significant increase in lipid signals. 0.9, 1.3, 2.3, 2.8, and 5.3 ppm was found in animals with 2 weeks(p<0.01). Therefore, $^1H$-MRS is useful in detecting and characterizing various hepatic lipid alterations as early as 2 weeks for the start high fat diet.

• Journal of Industrial Convergence
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• v.21 no.1
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• pp.95-102
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• 2023

This study was to identify the factors affecting nurses' use intention of digital healthcare and the moderating effect of clinical career based on the UTAUT model. The items were composed by performance expectancy 3 items, facilitation condition 3tiems, and perceived risk 3 items. CFA was performed to verify the construct validity. As a results, average variance extracted (AVE) was .5 or higher, and construct reliability (CR) was .7 or higher. Model fit was confirmed as CMIN/df=1.797, GFI=.955, CFI=.979, TLI=.968, IFI=.979, and RMSEA=.063. The internal reliability was .93 for performance expectancy, .84 for facilitating conditions, and .64 for perceived risk. Performance expectancy, facilitating condition, and perceived risk had a significant effect on use intention, and clinical career showed a moderating effect(t=-2.159, p=.032). Therefore, in order to enhance the use intention of digital health care, performance expectancy, and facilitating conditions should be raised and perceived risk should be reduced.

• Journal of Korean Port Research
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• v.13 no.1
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• pp.51-64
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• 1999

This study is on the focus of the cost-effective and time-effective in the BCTOC which commenced the On Dock Termainal System in 1998 for the first time in Korea. On this process of study two categories should be considered : (1) Improvement on Business Process (2) Improvement on Information Technology. With these two accesses a new future-oriented and prospective model could be put on our hand as follows. (1) Improvement on Business Process \circled1Consistency of container In-Out Operation \circled2Simplicity of Rate appraisal \circled3Unified operation on Billing and Request (2) Improvement on Information Technology \circled1Scale up the Information Application \circled2Constructing an one-spot simultaneous Information Holding System \circled3Combination of Internet and Integrated Database System.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.9
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• pp.1091-1097
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• 2011

The SGBEM-FEM alternating method has been known to be a very effective method for analyzing threedimensional cracks in a finite body. The accurate values of the stress intensity factor can be obtained for a general planar or nonplanar three-dimensional crack. In the existing method, eight-noded quadrilateral boundary elements are used to model a crack. In some cases, three-node triangle boundary elements are more convenient for the modeling of a crack with a general shape. In this study, a crack is modeled with three-noded triangular and seven-noded quadrilateral elements by using the advancing-front mesh generation method. The stress intensity factors are obtained for cracks with several shapes and the accuracy of results is examined.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.232-239
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• 2020

The purpose of this study was to identify the effect of stress and sense of coherence on health behavior compliance in patients with stroke. The subjects were 124 outpatients with stroke at a general hospital in Ulsan from May to July, 2019. The data were analyzed using descriptive statistics, t-test, one-way ANOVA, Scheffé test, Pearson's correlation coefficient and hierarchical multiple regression analysis by using SPSS 25.0. In the results, the health behavior compliance showed a significantly positive correlation with sense of coherence(r=.71, p<.001) and a negative correlation with stress(r=-.53, p<.001). The predictors of model 1 were gender(t=4.07, p<.001), education level(t=4.18, p<.001), and monthly income(t=-2.34, p=.021) and the statistical power was 39.6%. The predictors of model 2 were gender(t=4.65, p<.001), education level(t=43.24, p<.001), and sense of coherence(t=4.33, p<.001) and the statistical power was 60.4%. Thus, a nursing intervention program which is focused on a sense of coherence could promote health behavior compliance in patients with stroke.

• The Journal of the Korea Contents Association
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• v.22 no.5
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• pp.656-666
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• 2022

The purpose of this study is to evaluate the effect on the grit, learning reality, and learning satisfaction for nursing students using the flipped learning teaching method. We developed a flipped learning educational program using ADDIE model for nursing students and evaluated the program effect. As a result of this study, the grit (t=-3.07, p=.003), the learning presence (t=-4.87, p<.001) and the learning satisfaction (t=-5.18, p<.001) significantly increased after flip learning method application. The Grit shown to have a significant positive correlation with learning presence (r = .47, p<.001), and learning satisfaction (r = .26, p<.005). The learning presence shown to have a significant positive correlation with learning satisfaction (r = .548, p<.001). The flipped learning teaching method may improve the grit, learning reality, and learning satisfaction. Various efforts will be needed to lay the foundation for flipped learning teaching methods in the field of nursing education in the future.