• Journal of Environmental Health Sciences
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• v.44 no.3
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• pp.205-216
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• 2018

Objectives: Scientific verification for health effects has been constantly demanded through the forest healing factors. In this study, phytoncide concentration which is one of the forest healing factors, was investigated according to stand density, season and visiting time, and analyzed correlation with micrometeorology factors. Methods: Total volatile organic compounds (TVOCs) and Natural volatile organic compounds (NVOCs) were collected using a measuring instrument which is connected to an air pump with the Tenax TA tube. The 32NVOCs were selected through the detailed criteria of adequacy assessment for recreational forest. The statistical analysis (correlation and stepwise regression analysis) was conducted between phytoncide concentration and micrometeorology factors. Results: NVOCs concentration linearly increased according to stand density. The high level showed in the summer (p<0.05), and there is no significant difference according to visiting hours of the Healing forest. NVOCs is a negative correlation with solar radiation, PAR and wind direction, and a positive correlation with relative humidity and temperature (p<0.01). NVOCs increased following the increase of humidity and temperature ($R^2=0.55$). Conclusions: Phytoncide linearly increased according to stand density, and showed the correlation significantly with microclimate factors. In future, these results will be utilized as a basic material to promote the generation of phytoncide, which positively influences human health promotion and manage the forest welfare space.

• Journal of The Korean Association of Information Education
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• v.17 no.3
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• pp.291-304
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• 2013

Considering the change of educational environments and strategies for the future, this research attempted to develop project learning that uses various smart technologies, and integrates formal education within a school with informal learning experiences outside of the school. For effective learning, the processes of the project learning, instructional activities for each process and supporting materials were specified and developed as a learning package. The project learning program and the instructional package were applied to 18 fifth graders in an elementary school located in Seoul. The results of the pilot test were collected with observations, interviews, and assessment of learning processes and products. And then the results were analyzed in regard of 'the whole processes of project activities', 'learning materials and tools', and 'informal learning experiences'. Based on the results, some suggestions were provided for implementing the smart project learning for integrative learning experiences.

• Korean Journal of Veterinary Service
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• v.42 no.4
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• pp.183-191
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• 2019

Claw lesion is one of the major causes of lameness in sows and the lameness is one of the reasons for culling of sows from the swine herd. This survey was conducted on sows in total of 8 farms with a total of 684 pigs. The lesions observed in the study were horizontal and vertical claw cracks (CWH & CWV), differences in the length of toes (T) and/or in the length of dew claws (DC) according to crates, breeds and parity of sows. Scores of claw lesions were assigned on 0, 1, 2, and 3 at each foot depending on the severity of the claw lesions. The sows' parity was classified into 1 to 2, 3 to 4, 5 to 8. Prevalence rate of claw lesions in sows raised on punched plastic crate was higher than that in sows raised on tribar crate. In prevlence rate by breeds, inbreed Landrace sows showed higher than that of Yorkshire sows. According to 4 claw lesions, the length of DC was the highest at parity 3~4 and CWV was the lowest at parity 3~4 in F1 crossbred sows raised on punched plastic crates, respectively. In Yorkshire breeds raised on punched plastic crates, the length of DC at parity 5~8 was the lowest and CWH was the highest at parity 3~4, respectively. In Landrace breeds raised on tribar crates, CWH was the highest at parity 1~2 and CWV was the lowest at parity 3~4, respectively. The high parity in F1 crossbred sows showed high prevalence rate of claw lesions than that of low parity and other inbreed sows, respectively. These results may be useful as elementary data in establishment of welfare quality protocol and preventive measures to reduce economic losses from craw lesions in sows.

• Journal of Radiation Protection and Research
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• v.43 no.3
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• pp.97-106
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• 2018

Background: A cargo container scanner using a high-energy X-ray generates a fan beam X-ray to acquire a transmitted image. Because the generated X-rays by LINAC may affect the image quality and radiation protection of the system, it is necessary to acquire accurate information about the generated X-ray beam distribution. In this paper, a diode-based multi-channel spatial dose measuring device for measuring the X-ray dose distribution developed for measuring the high energy X-ray beam distribution of the container scanner is described. Materials and Methods: The developed high-energy X-ray spatial dose distribution measuring device can measure the spatial distribution of X-rays using 128 diode-based X-ray sensors. And precise measurement of the beam distribution is possible through automatic positioning in the vertical and horizontal directions. The response characteristics of the measurement system were evaluated by comparing the signal gain difference of each pixel, response linearity according to X-ray incident dose change, evaluation of resolution, and measurement of two-dimensional spatial beam distribution. Results and Discussion: As a result, it was found that the difference between the maximum value and the minimum value of the response signal according to the incident position showed a difference of about 10%, and the response signal was linearly increased. And it has been confirmed that high-resolution and two-dimensional measurements are possible. Conclusion: The developed X-ray spatial dose measuring device was evaluated as suitable for dose measurement of high energy X-ray through confirmation of linearity of response signal, spatial uniformity, high resolution measuring ability and ability to measure spatial dose. We will perform precise measurement of the X-ray beamline in the container scanning system using the X-ray spatial dose distribution measuring device developed through this research.

• Clinical and Experimental Pediatrics
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• v.59 no.4
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• pp.183-189
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• 2016

Purpose: This study aimed to evaluate the correlation, according to postnatal age, between plasma B-type natriuretic peptide (BNP) levels and echocardiographic parameters for the assessment of patent ductus arteriosus (PDA) in preterm infants with respiratory distress. Methods: We enrolled 42 preterm infants with respiratory distress who underwent serial echocardiographic evaluation with simultaneous plasma BNP measurements until ductal closure. The correlations between BNP levels and the following 4 representative echocardiographic parameters were studied: diameter of the ductus arteriosus (DA), ratio of the left atrial diameter to the aortic diameter (LA/Ao), ratio of the PDA diameter to the infant's left pulmonary artery diameter (PDA/LPA), and the antegrade diastolic flow of LPA (DFLPA). Results: BNP levels were significantly correlated to the magnitude of the ductal shunt, comprising the DA diameter, PDA/LPA ratio, LA/Ao ratio, and antegrade DFLPA for the overall study period. The earliest significant correlation, starting from postnatal day 2, was observed between the LA/Ao ratio and BNP levels. The PDA/LPA ratio and the antegrade DFLPA showed significant correlations with BNP levels postnatal day 3 onward, and with the DA diameter, postnatal day 5 onward. Conclusion: BNP levels and echocardiographic parameters showed a positive correlation, but the significance of the correlations differed according to the postnatal age, especially during the first few days of life.

• Korean Journal of Social Welfare
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• v.69 no.3
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• pp.289-315
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• 2017

Debate on basic income expanded worldwide as well as in South Korea. However, the expansion of these discussion has led to vigorous arguments for and against the various claims of basic income. In order to introduce basic income in Korea, discussing on the picture of Korean welfare state which includes basic income is important. In this study, 'Ideal Model of Korean Basic Income (and Welfare State)'is discussed and theoretically constructed using fuzzy-set ideal type approach, and feasible paths in realizing Korean basic income are suggested. This study attempts to contribute to a practical discussion on taking feasible and reasonable path to realize full basic income in Korean welfare state.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.6
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• pp.498-506
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• 2016

A croquette added with heat-treated kimchi at 20% showing higher sensory preferences was analyzed for its physicochemical properties and antioxidant activity using a croquette without kimchi as a control. Compared with the control, kimchi-added croquette had 3.3-fold higher organic acids content (p<0.001), resulting in a significant reduction of pH (p<0.001) and higher metal chelating activity (p<0.001). Upon addition of kimchi, total reducing capacity increased from 109.4 to $139.4{\mu}g/g$ gallic acid equivalents (p<0.01), and DPPH radical scavenging activity also increased 2-fold, which corresponded to 54% of the electron-donating ability of 0.35 mM gallic acid. In addition, contents of free amino acids and ${\gamma}-aminobutyric$ acid (GABA) appreciably increased by 1.6-fold (p<0.01) and 10-fold (p<0.001), respectively. This could be attributed to the ingredients of kimchi and/or enzymatic transformation of precursors by microorganisms during kimchi fermentation. Kimchi-added croquette was determined to be a good source of dietary fiber relative to its calorie content. Texture profile analysis showed no significant differences in hardness, springiness, cohesiveness, gumminess, and chewiness between the two croquettes with or without kimchi. Taken together, this study shows that utilization of heat-treated kimchi as a filling for croquette could be a good strategy to improve both the nutritional quality and antioxidant activity of croquette.

• Korean Journal of Materials Research
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• v.28 no.11
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• pp.646-652
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• 2018

During a long-term operation of polymer electrolyte membrane fuel cells(PEMFCs), the fuel cell performance may degrade due to severe agglomeration and dissolution of metal nanoparticles in the cathode. To enhance the electrochemical durability of metal catalysts and to prevent the particle agglomeration in PEMFC operation, this paper proposes a hybrid catalyst structure composed of PtCo alloy nanoparticles encapsulated by porous carbon layers. In the hybrid catalyst structure, the dissolution and migration of PtCo nanoparticles can be effectively prevented by protective carbon shells. In addition, $O_2$ can properly penetrate the porous carbon layers and react on the active Pt surface, which ensures high catalytic activity for the oxygen reduction reaction. Although the hybrid catalyst has a much smaller active surface area due to the carbon encapsulation compared to a commercial Pt catalyst without a carbon layer, it has a much higher specific activity and significantly improved durability than the Pt catalyst. Therefore, it is expected that the designed hybrid catalyst concept will provide an interesting strategy for development of high-performance fuel cell catalysts.

• Journal of the Korean Wood Science and Technology
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• v.49 no.6
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• pp.591-601
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• 2021

Recently it is trend to increase wood use as carbon neutral materials, there is recognized to need necessarily durability improvement of wooden building. It is very rare to report existing on the identification of isolates causing discoloration in domestic weathered wooden building used for long period. The objective of this study was identification of fungi that cause discoloration on the exteriors of weathered domestic wooden buildings in the southern part of South Korea. Our findings can be helpful to establish protection technology for weather deterioration of domestic wooden buildings. Wood chip samples presumed to be contaminated with sapstain fungi were collected from the surface of wooden members used in wooden buildings at Jangheung, Jeollanam-do (two locations, #13 and #14), and Jeju Island (two locations, #31 and #33). The growth of microorganisms was confirmed by performing culture tests for the collected samples, and fungi were isolated, purified, and identified. The results indicated that the fungal strains isolated from wooden buildings #13 and #14 at Jangheung, Jeollanam-do, were 99.83% and 100% homologous to Aureobasidium melanogenum, respectively. For wooden building #31 at Jeju Island (two locations), the fungal strain isolated was 100% homologous to A. melanogenum, which is the same species isolated from the wooden buildings at Jangheung. The fungal strain isolated from wooden building #33 (Jeju Island) had 99.83% homology with A. pullulans, which is commonly found in wood degraded by weather or ultraviolet rays. Our findings can be utilized as a basis for establishing protection technology in domestic wooden buildings.

• Journal of the Korean Chemical Society
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• v.64 no.6
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• pp.389-400
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• 2020

The purpose of this study was to examine the effects of Argument-based Inquiry activities on the claims and evidence in elementary students' science writing. Participants were thirty three fifth grade elementary school students and argument-based inquiry activities on five topics were implemented. We analyzed the Summary Writing samples written by students to investigate the effect of the Argument-based inquiry activities on elementary students' claims and evidence in their science writing, and also analyzed the writing samples of the experimental group to which the Argument-based inquiry activities were implemented, to examine the change of claims and evidence. The results of this study showed that the mean of experimental group was significantly higher than that of the comparison group. As a result of analyzing claims and evidence in Summary Writing of experimental group, the level of claim and evidence has tended to increase gradually as the number of classes progresses.