• Asia pacific journal of information systems
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• v.23 no.4
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• pp.103-128
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• 2013

When a consumer needs a product or service and multiple sellers are available online, the process of selecting a seller to buy online from is complex since the process involves many behavioral dimensions that have to be taken into account. As a part of this selection process, consumers may set minimum trust expectation that can be used to screen out less trustworthy sellers. In the previous research, the level of consumers' trust expectation has been anchored on two important factors: product involvement and perceived risk. Product involvement refers to the extent to which a consumer perceives a specific product important. Thus, the higher product involvement may result in the higher trust expectation in sellers. On the other hand, other related studies found that when consumers perceived a higher level of risk (e.g., credit card fraud risk), they set higher trust expectation as well. While abundant research exists addressing the relationship between product involvement and perceived risk, little attention has been paid to the integrative view of the link between the two constructs and their impacts on the trust expectation. The present paper is a step toward filling this research gap. The purpose of this paper is to understand the process by which a consumer chooses an online merchant by examining the relationships among product involvement, perceived risk, trust expectation, and intention to buy from an e-tailer. We specifically focus on the mediating role of perceived risk in the relationships between enduring product involvement and the trust expectation. That is, we question whether product involvement affects the trust expectation directly without mediation or indirectly mediated by perceived risk. The research model with four hypotheses was initially tested using data gathered from 635 respondents through an online survey method. The structural equation modeling technique with partial least square was used to validate the instrument and the proposed model. The results showed that three out of the four hypotheses formulated were supported. First, we found that the intention to buy from a digital storefront is positively and significantly influenced by the trust expectation, providing support for H4 (trust expectation ${\rightarrow}$ purchase intention). Second, perceived risk was found to be a strong predictor of trust expectation, supporting H2 as well (perceived risk ${\rightarrow}$ trust expectation). Third, we did not find any evidence of direct influence of product involvement, which caused H3 to be rejected (product involvement ${\rightarrow}$ trust expectation). Finally, we found significant positive relationship between product involvement and perceived risk (H1: product involvement ${\rightarrow}$ perceived risk), which suggests that the possibility of complete mediation of perceived risk in the relationship between enduring product involvement and the trust expectation. As a result, we conducted an additional test for the mediation effect by comparing the original model with the revised model without the mediator variable of perceived risk. Indeed, we found that there exists a strong influence of product involvement on the trust expectation (by intentionally eliminating the variable of perceived risk) that was suppressed (i.e., mediated) by the perceived risk in the original model. The Sobel test statistically confirmed the complete mediation effect. Results of this study offer the following key findings. First, enduring product involvement is positively related to perceived risk, implying that the higher a consumer is enduringly involved with a given product, the greater risk he or she is likely to perceive with regards to the online purchase of the product. Second, perceived risk is positively related to trust expectation. A consumer with great risk perceptions concerning the online purchase is likely to buy from a highly trustworthy online merchant, thereby mitigating potential risks. Finally, product involvement was found to have no direct influence on trust expectation, but the relationship between the two constructs was indirect and mediated by the perceived risk. This is perhaps an important theoretical integration of two separate streams of literature on product involvement and perceived risk. The present research also provides useful implications for practitioners as well as academicians. First, one implication for practicing managers in online retail stores is that they should invest in reducing the perceived risk of consumers in order to lower down the trust expectation and thus increasing the consumer's intention to purchase products or services. Second, an academic implication is that perceived risk mediates the relationship between enduring product involvement and trust expectation. Further research is needed to elaborate the theoretical relationships among the constructs under consideration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4234-4243
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• 2010

Dementia such as poor concentration, anxiety and tension makes it hard to continue exercise in reality. For this, intermediate exercise is suggested in this study. And the study investigates the effects on senior fitness, cognitive function(MMSE-K) and daily living activity(ADL) by continuous exercise and intermittent exercise, which helps to provide proper exercise treatment to them. For this, female elderly patients at A dementia hospital in B Metropolitan city are selected and they have been diagnosed with possible Alzheimer's disease according to DSM-IV. Among them, six(6) are grouped for continuous exercise and five(5) for intermediate exercise, total 11 people are finally tested. They are given hand&foot exercise, Korean folk dance and band exercise three times a week for the total 12 weeks. The continuous exercise group does their exercise one time of 30 minutes a day while the intermediate exercise group for three times of each 10 minute a day. For the result, SPSS Ver. 18.0 is used to get mean value(M) and standard deviation(SD) and in order to verify the interaction effect between exercise group and time, two-way repeated ANOVA is applied and statistical significance level is set at .05. The result shows that there is significant difference in time between senior fitness and cognitive function. But there is no significant difference in group and time${\times}$group. And there is no significant difference in time, group and time${\times}$group for daily living activity. Continuous exercise group and intermediate exercise group both have the similar effects. That does not mean that intermediate exercise is the best for all people with dementia, but in terms of exercise time, intermittent exercise may be effective for patients of light dementia.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.71-76
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• 1998

To know the antibiotic specificity of a Dinoflagellate, Cochlodinium polykrikoides, we investigated the survival time of C. polykrikoides against several concentrations of antibiotics and judged the selective specificity of antibiotics based on the $LT_50$ ($50\%$ of lethal time). The result showed that C. polykrikoides was sensitive to tetracycline and chloramphenicol, and resistant to polymixin-B, ampicillin, penicillin-G, dihydrostreptomycin, and neomycin. In the case of sensitive antibiotics to C. polykrikoides, tetracycline and chloramphenicol, the safety concentrations of both antibiotics were determined and the antibiotic specificity based or the plotted survival curve was analyzed. Before antibiotic treatment, we tested the antibiotic susceptibility of the contaminated bacterial population in tile culture of C. polykrikoides, and decided the proper kinds of antibiotics and concentrations before percoll-centrifugation. By percoll-centrifugation, we reduced bacteria, removed fungi, collected the algal pellet, and made axonic culture by antibiotic cascade procedure based on the result of antibiotic susceptibility test. We observed that axonic C. polykrikoides culture entered the logarthmic phase of growth when cell density was over 740 cells/ml and propagated to 5,800 cells/ml maximally. Divisions per day, k value of C. polykrikoides represented a good index for growth at the low density of cells. There was a highest k value shift before reaching to the logarithmic phase. We suggested that the preceeding highest k value shift stage is a good indicator for accurate broadcasting for red. tide blooming in the field, and the stage is also a good time for controlling red tide blooming in the filed, either.

• Korean Journal of Family Social Work
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• no.54
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• pp.297-331
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• 2016

The purpose of this study was to examine the mediating roles of neglectful rearing attitudes and mental health in the relationship between economic status of single-parent famillies and school adjustment, and the differences between single-parent and two-parent families, using structural equation modeling. Data were obtained from the Middle School 1 Panel(third-wave) of the Korean Child and Youth Panel Survey 2010. This study selected 2,195 middle school 3th-grade students (249 from single-parent families and 1,946 from two-parent families). Data were examined with structural equation modeling and multi-group analysis using AMOS 21.0, and mediating effects were tested using the Sobel test. The results were as follows; First, the single-parent children reported lower levels of economic status and school adjustment, and higher levels of neglectful rearing attitudes than the two-parent children. Second, multi-group analysis showed a statistically significant difference between single-parent and two-parent in structural equation modeling. Economic status of two-parent famillies affected school adjustment of children, but economic status of single-parent famillies did not affect school adjustment of children. Third, as a result of examining for total effect, the variable that most influenced school adjustment of children was neglectful rearing attitudes. Fourth, neglectful rearing attitudes and mental health did play a mediating role in the relationship between economic status and school adjustment in case of two-parent famillies, but neglectful rearing attitudes and mental health did not play a mediating role in case of single-parent famillies. Based on the result, this study stressed the following; First, the study suggested that problem of the single-parent famillies supporting standard which is concentrated on the low income single-parent famillies. Second, the study proposed multifaceted support measures which reflects characteristics of single-parent famillies to increase school adjustment of the single-parent children.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.229-240
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• 2009

The high temperature and water content in soil profile probably affect the physiological disorder especially on cool-season turfgrasses in warm and humid weather of Korean summer. The purpose of this research was to analyze the effect of soil temperature and water content on the growth and stress response of creeping bentgrass(Agrostis palustris Huds.) under a humid and warm temperature. USGA(United State of Golf Association) green profile in laboratory test, Daily temperature changes were tested under a dried sand, 70% water content of field capacity, and saturated condition at $34^{\circ}C$ of the USGA green in lab. In this test, the dried sand reached to $80^{\circ}C$, however, the surface temperature decrease of $10^{\circ}C$ on the saturated condition. In the thermal properties test in field, thermal conductivity, thermal diffusivity, and soil temperature were increased followed by irrigation practise. In the water-deficient condition, the highest soil temperature was reached temporally right after irrigation, however, the excessive soil water content higher than field water holding capacity showed the highest soil temperature after a while. This result indicated that a heat damage to root system was caused from the thermal conductivity of a high surface soil temperature. The excessive irrigation when a high turf surface temperature should occur a negative result on tufgrass growth, moreover, it would be fatal to root growth of creeping bentgrass, especially when associated with a poor draining system on USGA sand green. Overall, this study shows that high soil temperature with water-excessive condition negatively affects on cool-season grass during the summer season, suggesting that excessive irrigation, over 70% field capacity of soil condition, does not help to reduce soil temperature for summer season in Korea. In the study that cool-season grass were treated with different water content of soil, The soil had higher temperature and more water holding capacity when treatment rate of soil conditioner was increased. The best growth at the normal water condition and the worst state of growth at thee water-excessive condition were observed.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.400-408
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• 2018

Biodiversity has continued to degrade in the $21^{st}$ century due to global warming occasioned by destruction of the environment around the world.. The Nagoya protocol places Korea in a unique position to effectively develop and protect its domestic genetic resources. Microalgae under study in this research contains large amount of antioxidant substances such as beta carotene and astaxanthin, that can be used as biological resource owing to the large amounts of biomass that can be secured through photosynthesis. However, it is difficult to preserve it since cryopreservation method used for long-term preservation is yet to be developed. A basic study for long term cryopreservation was carried out on Nizschia frustulum and Nitzschia amabilis which belong to marine diatoms. As cryoprotectants (CPAs), glycerol, DMSO, and methanol which penetrate into cells were prepared at 5%, 10%, and 15% concentrations each, in case of methanol, it was tested at concentrations of 5%, 10% and 12% by its nature. Two kinds of microalgae, N. frustulum and N. amabilis, were diluted with $10^2$, $10^3$ and $10^4cells\;ml^{-1}$, respectively. The highest survival rate was shown at12% concentration of methanol, and the figures were $6.94{\pm}0.31%$ in N. frustulum and $8.85{\pm}0.16%$ in N. amabilis. As a result of 3 weeks cultivation of thawed microalgae after freezing, the result is shows that N. frustulum increased about 10 times faster and N. amabilis increased about 12 times the original concentration.

• (The) Korean Journal of Educational Psychology
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• v.23 no.3
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• pp.645-663
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• 2009

The purpose of this study is to develop and verify a Korean Diagnostic Scale of Multiple Intelligence(MI), which will be an alternative test to avoid problems with former Shearer's MI test and to adopt H. Gardner's suggestions to develop MI assessment. The test is developed 5 types; kindergartner, elementary lower grader, elementary upper grader, middle schooler, high schooler test. A form of test is diversified with 3 types; multiple-choice items for accomplishment, true or false items for ability, and self-reported items with likert scale for interest and ability. According to H. Gardner's suggestions, we have tried to reanalyze key component of MI, analyze an overlapping or hierarchical relationship between intelligences, develop intelligences-fair items, diversify form of item. We have developed a final standardized test through a primary, secondary preliminary-test analysis, and sampled 5,585 students by age, gender, and regional groups. As a result of this sampling test, we can get a norm score and compare individuals with other's score relatively. To verify this test, we analyzed behavior observation, mean, standard deviation, a percentage of correct answers, reliability of each test type, correlation between intelligence scales, Kruskal-Wallis test of mean rank of career choice by intelligences. As a result of correlation analysis between sub-intelligence scales, we can conclude that this MI test is satisfied with intelligence independent assumption. Besides, as non-parametric statistics test(Kruskal-Wallis) of career choice by intelligences, we can identify that MI is related with domain of career choice. This test is not a linguistic and logical-mathematical biased test but a intelligences-fair test. It makes us compare individual's potential with a norm score. Besides, it could be useful as a means of educational prescription or counsel in comparison with ability, interest, and accomplishment of individual. But this test is limited to do factor or correlation analysis between types of sub-test, because items are minimized for a time-constraint and a heavy burden of test receiver. But if it could be tested with increased items by two sessions, further research could be expected to get over this constraints and do a further validation analysis.

• Pediatric Infection and Vaccine
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• v.26 no.2
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• pp.81-88
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• 2019

Purpose: Early detection of Mycoplasma pneumoniae is important for appropriate antimicrobial therapy in children with pneumonia. This study aimed to evaluate the diagnostic value of a rapid antigen test kit in detecting M. pneumoniae from respiratory specimens in children with lower respiratory tract infection (LRTI). Methods: A total of 215 nasopharyngeal aspirates (NPAs) were selected from a pool of NPAs that had been obtained from children admitted for LRTI from August 2010 to August 2018. The specimens had been tested for M. pneumoniae by culture and stored at $-70^{\circ}C$ until use. Tests with Ribotest $Mycoplasma^{(R)}$ were performed and interpreted independently by two investigators who were blinded to the culture results. Results: Among the 215 NPAs, 119 were culture positive for M. pneumoniae and 96 were culture negative. Of the culture-positive specimens, 74 (62.2%) were positive for M. pneumoniae by Ribotest $Mycoplasma^{(R)}$, and 92 of the 96 (95.8%) culture-negative specimens were negative for M. pneumoniae by Ribotest $Mycoplasma^{(R)}$. When culture was used as the standard test, the sensitivity and specificity of Ribotest $Mycoplasma^{(R)}$ were 62.2% and 95.8%, respectively. Additionally, the positive predictive value, negative predictive value, and overall agreement rates with Ribotest $Mycoplasma^{(R)}$ were 94.9%, 67.2%, and 77.2%, respectively. Conclusions: A positive test result of Ribotest $Mycoplasma^{(R)}$ suggests a high likelihood of culture-positive M. pneumoniae infection. However, a negative test result should be interpreted with caution because nearly one-third of negative test results reveal culture-positive M. pneumoniae infections.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.4
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• pp.94-104
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• 2018

This study examined photogrammetric reconstruction techniques that can measure the original form of a cultural property utilizing photographs taken in the past. During the research process, photographs taken in the past as well as photograph on the internet of Soswaewon Garden in Damyang(scenic site 40) were collected and utilized. The landscaping structures of Maedae, Aiyangdan, Ogokmun Wall, and Yakjak and natural scenery Gwangseok, of which photographs can be taken from any 360 degree direction from a close distance or a far distance without any barriers in the way, were selected and tested for the possibility of reproducing three-dimensional shapes. The photography method of 151 landscape photographs (58.6%) from internet portal sites for the aforementioned five landscape subjects containing information on the date the photograph was taken, focal length, and exposure were analyzed. As a result of the analysis, it was revealed that the majority of the photographs tend to focus on important parts of each subject. In addition, we discovered that there are two or three photography methods that internet users preferred in regards to each landscape subject. For the purposes of the experiment, photographs in which a single scene consistently appears for each landscape subject and it was determined that there was a high level of preference related to the photography method were analyzed, and three-dimensional mesh shape model was produced with a photoscan program to analyze the reproducibility of three-dimensional shapes. Based on the results of the reproduction, it was relatively possible to reproduce three-dimensional shapes for artifacts such as Ogukmun wall, Maedae, and Aeyangdan, but it was impossible to reproduce three-dimensional images for natural scenery or an object that has similar texture such as Yakjak and Gwangseok. As a result of experimentation related to the reconstruction of three-dimensional shapes with the photographs taken on site using a photography method similar to that of the photographs selected as previously mentioned, there was success related to reproducing the three-dimensional shapes of Yakjak and Gwangseok, of which it was not possible to do so through the photographs that had been collected previously. In addition, through comparison of past and present images, it was possible to measure the exact sizes as well as discover any changes that have taken place. If past photographs taken by tourists or landscape architects of cultural properties can be obtained, the three-dimensional shapes from a particular period of time can be reproduced. If this technology becomes widespread, it will increase the level of accuracy and reliability in regards to measuring the past shapes of cultural landscape properties and examining any changes to the properties.

• The Korean Journal of Nuclear Medicine Technology
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• v.25 no.1
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• pp.29-33
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• 2021

Purpose Plasma renin activity (PRA) test is important for the diagnosis of primary aldosteronism. PRA is an easily deformed substance in vitro and affected by temperature changes. Laboratory of ASAN medical center has consistently found that there was a difference between the initial and re-experimental results. We compared and analyzed the differences in PRA test results according to the sample storage status. Materials and Methods The measurement of PRA was performed by using the radioimmunoassay. From August to September 2020, 43 PRA re-test samples were tested with different sample storage condition. The first group was re-examined by freezing the plasma-separated samples at -18℃, and the second group was re-examined with refrigerated EDTA sample. Also, additional tests were conducted on 13 PRA samples to verify the effect on thawing temperature differences in plasma-separated samples. The same samples were divided into two parts and stored frozen at -18℃, respectively, and thawing samples in room temperature and those in refrigerator were were conducted. Each result was compared and analyzed based on the initial experimental results. Results The results of re-examination after frozen storing plasma separation samples showed a lower correlation than the results of re-examination with EDTA plasma samples in refrigerator. When calculating the percentage based on the initial test results, the average percentage of each was 404.9% and 133.8%. The correlation coefficient was also R=0.8501 and R=0.9966, respectively, showing a higher correlation between plasma in the refrigerated sample EDTA tube. In comparison experiments with differences in thawing temperature, average percentage of the results of initial test and room temperature thawing was 94.3% and the average percentage of the results of refrigerated thawing was 88.0%. After again freezing the sample, the average percentage of the second room temperature thawing result is 107.5%, and the second refrigerated thawing group is 112.7%. Both groups showed an increase from first thawing. Conclusion A comparative analysis of retesting according to differences in sample storage methods in PRA tests showed a higher correlation between the results of retesting of the refrigerated EDTA plasma. And repeated freezing and melting of plasma separation samples, regardless of temperature during defrosting, has been shown to affect results. Therefore, retest of PRA should re-collect plasma from original EDTA plasma to increase reproducibility.