• The Mathematical Education
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• v.47 no.4
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• pp.447-465
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• 2008

The purpose of this study is to suggest effective teaching methods on the concept of infinity for students to obtain the right concept in the middle school curriculum. Many people have thought that infinity is something vouge and unapproachable. But, nowadays it is rather something with a precise definition that lies at the core of modern mathematics. To understand mathematics and science very well, it is necessary to comprehend the concept of infinity. But students tend to figure out the properties of infinite objects and limit concepts only through their experience closely related to finite process, and so they are apt to have their spontaneous intuition and misconception about it. Since most of them have cognitive obstacles in studying the infinite concepts and misconception, mathematics teachers need to help them overcome the obstacles and establish the right secondary intuition for the concepts through good examples and appropriate explanation. In this study, we consider the developing process of the concept of infinity in human history and give some comments and suggestions in teaching methods relative to that concept with new suitable examples.

• Journal of Fisheries and Marine Sciences Education
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• v.11 no.2
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• pp.139-149
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• 1999

Thermal sprayed Ni-Cr alloy coating on the carbon steel was carried out erosion-corrosion test and electrochemical corrosion test in the marine environment. The erosion-corrosion behavior and electrochemical corrosion characteristics of substrate(SS400) and thermal sprayed Ni-Cr coating was investigated. The erosion-corrosion control efficiency of Ni-Cr coating to substrate was also estimated quantitatively. The main results obtained are as follows : 1) The weight loss rate of Ni-Cr coating layer by the erosion-corrosion compared with substrate was smaller. With the lapse of time, the weight loss rate of substrate was linearly increased in $25{\Omega}{\cdot}cm$ solution, but that of Ni-Cr coating became stable. 2) The corrosion potential of substrate became less noble than that of Ni-Cr coating layer, and the corrosion current density of Ni-Cr coating became lower than that of substrate. 3) The control efficiency of erosion-corrosion of Ni-Cr coating compared to substrate became more dull than that of corrosion in $25{\Omega}{\cdot}cm$ and $5000{\Omega}{\cdot}cm$ solution.

• Korean Journal of Medicinal Crop Science
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• v.24 no.5
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• pp.351-359
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• 2016

Background: We investigated the optimal aqueous extraction conditions for recovery of high yields of total phenolic compounds from roots of Arctium lappa L. (burdock, Asteraceae), and we compared their antioxidant capacity. Methods and Results: The antioxidant activity of the extracts was tested using 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)-diammonium salt, and oxygen radical absorbance capacity assays. In addition, the major phenolic compounds present in the extracts were determined by high performance liquid chromatography analysis. Our results suggest that the roasted burdock $100^{\circ}C$, 15 min extract exhibited the strongest radical scavenging activity and possessed the highest concentration of phenolic compounds. The polyphenol content of both dried burdock and roasted burdock significantly increased with increase in the extraction temperature and time. Conclusions: These results indicated a relationship between phenolic compound levels in burdock and their free radical scavenging activities. This suggests that phenolic compounds significantly increase the antioxidant potential of burdock extracts.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.1
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• pp.139-151
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• 2013

Recently, in the context of increased interest for marine tourism, Jeju region of South Korea has attractive waterfront space and also has potential requirements for development. The objective of this paper was to analyze the priority for resource development of waterfront in Jeju region. In order to calculate the importance of factors related to the development of waterfront in Jeju area, this study conducted exploratory factor analysis to extract the factors and established the AHP model based on the factors name focusing on a total of 198 tourists. In this study, in accordance with the procedures of AHP analysis, pairwise comparisons were conducted focusing on a total of 15 experts. Especially, difference test between groups (academics and bureaucratic) was conducted. In the 1st criterion for evaluation, 'exploring experience' factor is most important thing and 'facilities & infrastructure' factors were in the following order. In the secondary criterion, AHP analysis showed that experience facilities, environmental management, and absence of residents consciousness were the important factors. In the future time, the results of this research can be utilized as basic data in the aspects of tourism development in Jeju waterfront region.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.6
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• pp.691-699
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• 2014

The purpose of this study was to examine the effect of temple food intake on health improvement. The survey was conducted from September to October 2013. The subjects in this study were 46 adults who participated in short-term 'Temple Stay' program. Every meal was prepared according to prearranged temple food menu, and it was provided to subjects for 4 weeks. Dietary intake, anthropometric measurements and biochemical parameter were measured and nutritional & health status were analyzed to find the effect of the program. Nutrients content of the temple food was sufficient to dietary reference intake while content of fat, fiber, vitamin A and calcium from the meal was significantly higher than the subjects' usual diet. Mean body weight, BMI and blood pressure (systolic and diastolic) related with obesity and hypertension decreased after the program. The index referring to liver function and cardiovascular disease risk such as serum ALT, ${\gamma}$-GTP, TG and LDL decreased while HDL increased thereby showing positive effect. The above results anticipate that temple foods with an affirmative effect in improving health status have a potential benefit that can be applied to general food service. Further detailed study might provide information in developing healthy diet for a corresponding clinical problem.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3077-3083
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• 2010

The electrochemical detection of As(III) was investigated on a platinum-iron(III) nanoparticles modified multiwalled carbon nanotube on glassy carbon electrode(nanoPt-Fe(III)/MWCNT/GCE) in 0.1 M $H_2SO_4$. The nanoPt-Fe(III)/MWCNT/GCE was prepared via continuous potential cycling in the range from -0.8 to 0.7 V (vs. Ag/AgCl), in 0.1 M KCl solution containing 0.9 mM $K_2PtCl_6$ and 0.6 mM $FeCl_3$. The Pt nanoparticles and iron oxide were co-electrodeposited into the MWCNT-Nafion composite film on GCE. The resulting electrode was examined by cyclic voltammetry (CV), scanning electron microscopy (SEM), and anodic stripping voltammetry (ASV). For the detection of As(III), the nanoPt-Fe(III)/MWCNT/GCE showed low detection limit of 10 nM (0.75 ppb) and high sensitivity of $4.76\;{\mu}A{\mu}M^{-1}$, while the World Health Organization's guideline value of arsenic for drinking water is 10 ppb. It is worth to note that the electrode presents no interference from copper ion, which is the most serious interfering species in arsenic detection.

• Journal of the Korean Physical Therapy Association
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• v.13 no.1
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• pp.5-17
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• 1992

Depression in Spinal Cord Injury Patients Kang, Soon Hee, M.Ed., R.P.T. Dept. of Rehabilitation Medicine, Kyung-Hee University Medical Center Depressions have the potential to affect adversely the rehabilitation of patients with spi-nal cord iniury. The present study examined depression, functional independence, and demographic and medical characteristics for 49 spinal cord injury(SCI) patients. This investigation involved the administration of the Beck Depression Inventory, the Modified Barthel Index, and aquestionnaire consisted of 14 items, The results were as follows .1. Compared to normal subjects, SCI patients had significantly higher BDI scores.2. When the cut-off point of HDI scores was assumed 21, 26.1% of normal subjeets and 75.5% of SCI patients appeared to be depressed. Depression in SCT patients were not related with age, sex, marital status, injury evel, severity, duration, pain, functional independence and medical charge. Depression in SCI patients were related with education level, economic level, age at injury, motivation. Depression in normal subjects were related with age, education level, economic level, but not related with sex, marital status. There were significant differences at 30 items of BDI between normal subjects and SCI patients. The items were as fellows . 1 sadness, 2 pessimism, 3 failure, 4 dissat-isfaction, 5 guilt, 6 punishment. 7 self-dislike 9 suicidal, 10 crying, 11 irritability, 12withdrawl, 13 indecisive, 14 self-image, IS work inhibition, 16 insomnia, 17 fatigue,18 anorexia, 19 weight loss, 20 hypochondria, 21 libido loss.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.451-459
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• 2020

This study aims to examine the causality between production input and the price of rice in East Java, Indonesia. This study applied a quantitative method to understand in a comprehensive way the correlation between variables. The data used for this study were collected from several sources, including East Java Agriculture Office, Siskaperbapo.com, and Statistics Indonesia (BPS) of East Java. This research was carried out over five years, starting from 2014 to 2018. Furthermore, the data were analyzed using the Vector Error Correction Model (VECM) by employing E-Views (version 7). The findings of this study indicated that, in the long run, the population, rice production, and changes in people's income have a positive effect on price stability, but are inversely proportional if seen in the short term. In comparison, in the long run, farmer exchange rates variable has a negative impact on price stability, and inversely proportional in the short term, which has a positive effect. There are different implications when the people's income increases and the rice price declines; these have great potential to alleviate poverty in East Java, Indonesia. This is due to the fact that the price stability also concerns the welfare of the community.

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.2
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• pp.180-192
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• 2005

In this paper I tried quantitative measures of the rent-seeking for budgetary allocations in Korean fisheries. There is a great deal of ignorance about the level of rent-seeking that takes place as a consequence of government expenditures and the potential for influencing their allocation, and so the attempt by Kats and Rosenberg(1989) to measure this in terms of the extent of annual changes in these allocations was a significant step forward. The opportunity to concentrate net public expenditure benefits within the fiscal function of the state gives rise to rent-seeking by special interest taxpayer-citizens through government budget allocations, special interest groups and coalitions of special interest groups. There are several important implications of budgetary rent-seeking. Budgetary rent-seeking is composed of 'income' and substitution effects, the budgetary 'income' effect is the general increase in government expenditures from one period to another. According to result of this analysis, average expenditures were 17.0% of total fisheries budget in 1966-2005. Therefore, distribution of fisheries budget should be converted by indirect support systems to reduce these rent-seeking behaviors.

• Journal of Korean Elementary Science Education
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• v.27 no.3
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• pp.244-251
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• 2008

One of the problems with testing for the presence of $CO_2$ is that the results are not visible. In order to over-come this weak point, a new testing method was developed with BTB indicator equipment, that made the gas visible. After that, the experiment was performed and tested the effects of the new visible equipment. The visible equipment could be adapted to regular class use successfully. Also, it was effective in that it reduced waste of gas, minimized danger potential through use of $CO_2$ canisters and candle-sticks, and also increased knowledge about indicators. The new experimental method and equipment affected the students' interest. It is possible that the students' positive participation was due to their interest in the new apparatus and application of the visual senses. The new system was tested fer its effects on teaching content and helping to produce sustained memory of the content. There were no significant differences between the groups in terms of content learning on initial content memory. However, when students in both groups were tested 4 months later, the visual experiment group sustained memory performance, while the other group showed a significant decrease. Generally, boys score higher than girls in terms of interest and participation in experimental activities. In this case, however, there were no difference between groups. It may have been due to introduction of new equipment and different methods from the textbooks. So, this could increase participation in science using various experiments.