• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.4
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• pp.233-238
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• 2020

Process-based model (PBM), based on the interactions between endogenous physiological processes and many environmental factors, can be a powerful tool for estimating crop growth and productivity. Carbon acquisition and biomass accumulation are the main components in PBM, so it has become important to understand and integrate gas exchange process in crop model. This study aimed to assess the applicability of FvCB model (a leaf model of C3 photosynthesis proposed by Farquhar, von C aemmerer, and Berry (1980)) in onion (Allium cepa L.). For parameterization, two early-maturing onion cultivars, 'Singsingball' and 'Thunderball', grown in a temperature gradient plastic film house, were used in measuring leaf net CO2 assimilation rate (A), and then, parameter estimation was carried out for four parameters including Vcmax (maximum rate of carboxylation), Jmax (maximum rate of electron transport), TPU (rate of triose phosphate utilization), and Rd (Dark respiration rate). The gas-exchange model calibrated in this research is expected to be able to explain the photosynthetic responses of onion under various environmental conditions (R2=0.95***).

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.975-978
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• 1997

This Paper presents a high impedance fault (HIF) detection algorithm of distribution systems using wavelet transform. Two HIFs on dry soil and sandy soil were simulated on various load conditions in 22.9 kV distribution systems using EMTP, and the current wavelets were decomposed by wavelet transform. The current root mean square(rms) change, the index change rate and the relative amplitude change were used as the multi-criteria for a HIF detection. The index change rate and the relative amplitude were made using the wavelet coefficients.

• Korean Journal of Child Education & Care
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• v.18 no.1
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• pp.77-102
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• 2018

The objectives of this study were to analyze the longitudinal mediation effects of maternal parenting stress and psychosocial development of infant on the influence of paternal involvement during infancy to children's peer interactions. For these objectives, latent growth modeling was used and adapted to the data taken from the Panel Study on Korean Children(PSKC), Wave I (0-year olds) to Wave III (2-year olds) and Wave V(4-year olds) to Wave VII(6-year olds). During a total of six years, 1,018 parent responded. The major results of this study were as follows. First, maternal parenting stress(initial status) had a significant mediating effect on the influence of paternal involvement(initial status) to children's play interaction(initial status). Second, maternal parenting stress(initial status/change rate) had a longitudinal mediating eff ect on the influence of paternal involvements(initial status/change rate) to children's play disruption-disconnection interactions(initial status/change rate). Third, psychosocial development of infants(initial status/change rate) had a longitudinal mediating effect on the influence of paternal involvement(initial status/change rate) to children's play interactions(initial status/change rate). Fourth, psychosocial development of infant(initial status) had a significant mediating effect on the influence of paternal involvement(initial status) to children's play disruption-disconnection interactions(initial status). The implications of the findings of the current study and suggestions for future research were also discussed.

• Journal of health informatics and statistics
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• v.43 no.4
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• pp.290-299
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• 2018

Objectives: This study aimed to evaluate the change in weight and heart rate associated with the use of phentermine through meta-analysis based on the published literatures. Methods: Eight electronic databases, PubMed, EMBASE, Cochrane library, and five domestic databases were used to search the literature. Randomized controlled trials that evaluated the change in weight and heart rate with the use of phentermine compared with placebo were included in this study. The fixed-effect model weighted by the Mantel-Haenszel method was used in the meta-analysis, and the random-effects model was used when heterogeneity was present. Results: We included 12 studies comprising 677 patients. The change in weight observed with the use of phentermine (SMD = -1.37, 95% CI: -1.55, -1.19) was statistically significant compared with that observed with placebo. As per the subgroup analysis results, the change in weight by publication year, country, phentermine dosage, follow-up check was not heterogeneous. The change in heart rate observed with the use of phentermine (SMD = 0.64, 95% CI: 0.35, 0.92) was significant compared with that observed with placebo. Conclusions: Weight loss and increased heart rate were confirmed in phentermine compared with placebo.

• The Mathematical Education
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• v.61 no.3
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• pp.419-439
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• 2022

This study is based on Freudenthal's mathmatising process and the didactical phenomenology of linear function concept, I have described and examined the process in which students represent the constant rate of change into tables, graphs and equations and, in this way, how they construct mental objects and essence of the linear function concept. The students used the proportionality as composite units, when they represented the phenomenon with constant rate of change into tables. When representing in graphs, all but one student represented it into a line. There were differences among the students in the level they were using the given conditions, co-variation perspective, and corresponding rules when formulating equations. The students compared the relationship between two variables in a multiplicative way, and under the guidance of teachers they reached to the understanding that its relationship becomes a constant. Moreover, they could construct mental objects of a constant rate of change, understanding the situation where the relationship between time difference and distance difference becomes one value, namely speed. The students had difficulties in connecting the rate of change with the inclination of a line. The students constructed the essence (concept) of linear functions, after building and organizing the image that the rate of change is constant, the graph is linear, and the equation is formulated as y=ax+b (a: inclination, b: intercept).

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2785-2790
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• 2007

This study presents an impedance method of in-vitro characterization of the thrombotic potential of whole blood. Whole blood samples of 0.2 cc were put into a micro-cell with embedded three electrodes immediately after venepuncture at $37^{\circ}C$. Anti-coagulated blood samples were also collected for hematocrit and blood viscosity analyses. The rate of change of electron flow was measured, which indicates the inverse of the thrombotic potential. A sudden decrease in the rate of change of electron flow was observed at a time equal to approximately 110 seconds. This sudden decrease was significantly delayed in anti-coagulated samples. After the sudden decrease, the rate continued to decrease, reaching a minimum value in unadulterated samples while the change in the rate in the anti-coagulated ones was found rather moderate. Based on these preliminary findings, the present method may be of used as a new tool for the diagnosis of the thrombotic potential of whole blood.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.115-116
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• 2016

This study applied BS replacement mortar's ERCO to see what impact it has on moisture evaporation and contraction changes, and resulted in the following. Depending on the rate of change in length according to the cure method of BS replacement mortar, high-strength areas were shown to have a bigger increase in the rate of change in length than regular or low-strength areas, and differences in rate of change in length due to ERCO cure methods were shown to be slight. For rate of changes in mass, on the whole there was an increase in the order of dry curing, cover curing, 7-day water curing, and28-day water curing. A comprehensive view says that after removal of test piece specimens, ERCO application did not expect a sufficient curing effect in the BS area.

• The Korean Journal of Health Service Management
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• v.12 no.1
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• pp.1-11
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• 2018

Objectives : The purpose of this study was to identify the relationship between decision-making types, public entrepreneurship, and performance management of local public hospital directors. Methods : A questionnaire survey was carried out to assess the dependent variables of directors' decision-making types and public entrepreneurship. The analysis of management performance was carried out through a comparison between 2016 results of, data of variation rate on medical revenue and change rate on medical profit and results in 2015. Results : Results indicated that local public hospital directors who used rational decision-making showed better performance management. The analysis showed that enterprise had a greater positive effect (+) on variation rate of medical revenue than that of innovation. However, innovation had a higher positive effect (+) on change rate of medical profit than that of enterprise. These results suggest that innovation and enterprise have a major influence on performance management. Conclusions : The survey used for this study suggests that an education and training program is needed to improve public hospital directors' ability for rational decision-making, public entrepreneurship and performance management. Additionally, the policy change guaranteeing autonomy within the proper range is demanded that Local Public Hospital Director having spirit of innovation and enterprise achieves peak capacity and have responsibility for management.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.2
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• pp.257-269
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• 1996

The puropose of this study was to investigate the movement-fitness according to the surface changing of lower limb The experimental items were divided into the lower limb movements (5) and body-shapes (7). This study was done by the expansion and contraction rate consideration of length, girth Also, the lower half of body shape-change on the movements and body-shapes by flat shell was done simultaneously. The summarized findings resulted from experiments and investigation are suggested as follows; First, when commpared the expansion and contraction rate of the length and girth items, the expansion rate of the back crotch length (14~20%), hip girth (10~ 21%) and knee girth (6.2~18.5%) in rabbit leap movement was the most notable among all variables considered in this experimentation. On the others hand, the front croth length (-22~-52%) contracted remarkably. And big-thigh type was the most notable on the body-shape comparision. Second, in comparision of the expansion and contraction rate of the area on the blocks, the expansion of the hip (50~200%) and knee (51~74%) block was the most remarkable. Especially, in the sit on knees movement of the hip-down type expanded 209.4%. Third, in comparision of the lower half of body shape-change, on the movements and body- shapes by the flat shell, under the influence of knee-joint and hip-joint the shape-changs of the hip and knee block was the most notable. But the shape-change of the waist, abdomen, calf, and ankle was feeble.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.1
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• pp.1-9
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• 2015

In this study it was adopted on sea dike monitoring that the safety monitoring with statistical limits which was adapted usually on safety monitoring by measuring pressures, stresses or deformations. And also the hydraulic head loss rate change according to passage of time was calculated for the purpose of safety monitoring. Safety monitoring by setting the statistical limit on the measured pore water pressure graphs need to be supplemented with an additional method of monitoring because the difference between the rise and fall of the tide was irregular. Safety monitoring by the limits set from values predicted by linear regression and standard errors on the hydraulic head loss graph was not affected by irregularity of tide. But if the condition of an embankment is changed gradually and slowly, it will not be detected on the hydraulic head loss graph. The graph of hydraulic head loss rate for every 24 hours vs date showed clearly that the sea water blocking state was getting better or not even though it was changed gradually and slowly.