• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1A
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• pp.71-80
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• 2010

Bridge deck is directly influenced by environment and vehicle load, it is easily damaged so that it requires an appropriate repair and retrofit. Therefore, developing a bridge deck with high durability is necessary in order to minimize the maintenance of bridge deck and use it to its design life. In this study, static test was carried out to evaluate a fatigue capacity of steel-concrete composite deck, which was newly developed by supplementing problems of existing reinforced concrete deck. Based on results from the static test, fatigue load was decided, and fatigue test was conducted under the constant amplitude repeated load. From the fatigue tests, the S-N curve regarding principle structural details of composite deck was made, and characteristics of fatigue behavior was estimated by comparing and evaluating it with fatigue design criteria. In addition, fatigue design guideline was presented. As a result, it is found that each structural details of composite deck proposed by this study, such as upper flange of corrugated steel plate and middle section of it, shear connector and lower flange of corrugated steel plate, is satisfying the fatigue strength.

• Journal of Korea Entertainment Industry Association
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• v.13 no.6
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• pp.265-275
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• 2019

The purpose of this study was to analysis of the changes of the white noise on the change of the writing ability and hand function of the children with the intellectual disabilities and then provide the basic information about that. The subjects was 12 children with intellectual disabilities. White noise was applied to analyze the subjects' writing ability and hand function before and after application. The provision of the white noise was continuous and uniform through the white noise generator. The analysis of the writing ability was performed by using the KNISE-BAAT assessment and the writing, vocabulary and composing ability were evaluated for the writing ability of the subjects. Also, the analysis of the hand function was performed by using the pegboard sub-item of the Manual Function Test. The results of the writing ability showed the statistically significant increase of the writing and vocabulary ability, but in the case of the composing ability, there was no statistically significant increase in the composing ability. Also, the results of the hand function showed the statistically significant increase in the both hands. The use of the white noise should be considered as a compensatory approach to improve the writing ability and hand function of the children with intellectual disabilities. Also, in order to improve the level of the performance, learning level, and academic achievement of the children of the intellectual disabilities, the application of the white noise in the living and learning environment should be needed to consider.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.360-363
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• 2022

According to the 2018 Kaggle ML & DS Survey, among the proportions of frameworks for machine learning and data science, TensorFlow and Keras each account for 41.82%. It was found to be 34.09%, and in the case of development programming, it is confirmed that about 82% use Python. A significant number of machine learning and deep learning structures utilize the Keras framework and Python, but in the case of Python, distribution and execution are limited to the Python script environment due to the script language, so it is judged that it is difficult to operate in various environments. This paper implemented a machine learning and deep learning system using C# and Keras running in Visual Studio 2019. Using the Mnist dataset, 100 tests were performed in Python 3.8,2 and C# .NET 5.0 environments, and the minimum time for Python was 1.86 seconds, the maximum time was 2.38 seconds, and the average time was 1.98 seconds. Time 1.78 seconds, maximum time 2.11 seconds, average time 1.85 seconds, total time 37.02 seconds. As a result of the experiment, the performance of C# improved by about 6% compared to Python, and it is expected that the utilization will be high because executable files can be extracted.

• Asia Marketing Journal
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• v.15 no.2
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• pp.49-73
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• 2013

In this study, the author develops and tests a model that incorporates the mediating effects of two frontline employee psychological variables (emotional exhaustion and intrinsic motivation) based on job demand and resource model. As a form of environmental resource, person-organization fit was proposed as a leading factor of frontline employee boundary spanning behavior through emotional exhaustion and intrinsic motivation. All measures were adapted from or developed based on prior research. Data for the study were collected from a cross-sectional sample of retail bank employees in South Korea. Questionnaires were distributed to 500 frontline employees across several banks. Of these, 322 usable questionnaires were returned. To analyze the data, a structural equation model procedure using LISREL 8.5 was employed. Results show that an employee's perceived fit with his/her organization enhances intrinsic motivation and reduces emotional exhaustion. These mechanisms, in turn, increase the employee's boundary spanning behavior. These results support the notion that person-organization fit should be one of the factors affecting motivation, affect and attachment, and extends such an understanding to a purely service-based environment among customer contact employees. Results also confirms that P-O fit can be viewed as environmental resources, and the JD-R model provides a theoretical base in further studying the antecedent role of P-O fit on frontline employees's boundary spanning behavior through intrinsic motivation and emotional exhaustion. These results suggest that organizations have to do their best to manage P-O fit, be it through employee screening or training and workshops to try and align organization and employee values and objectives. If managers of organizations are positively evaluated by the employees, it will be easier for them to, give things of value to employees, such as sense of direction, values, and recognition, and receive other things in return such as esteem and responsiveness. Consequently, organizational leaders are not only able to manage employee experiences, but also their fit with the organization. Even if a manager cannot control employee P-O fit, this research suggests, that a focus on reducing emotional exhaustion rather than increasing intrinsic motivation seems optimal. This research also supports the idea that motivation has a direct association with a frontline employee's boundary spanning behavior. Even in situations where emotional exhaustion cannot be reduced, organizations may still influence frontline behaviors through motivation.

• Asia Marketing Journal
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• v.10 no.4
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• pp.35-64
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• 2009

In an effort to increase our understanding of green buying behavior, the present study proposes and tests a comprehensive model of how values influence attitudes toward the environment and preferences for green products in a cross-cultural setting. Data were collected from a survey with consumers in two cultures, diametrically different on values salient to environmental consumerism, the U.S. and Korea. As a result of model testing both at the national and multi-group levels, a refined, final model is presented. While the core human values were found to relate to environmental attitudes and green buying behavior, the patterns of the relationships among the variables emerged to differ between the two cultures, highlighting the importance of cross-cultural investigations in this area. Results suggest that biospheric values significantly influence environmental attitudes and green consumption in both countries. However, the effects of egoism were significant among American respondents whereas altruism appeared to have a significant influence on attitude and behavior in the Korean sample. Findings of this study should aid international marketers in their understanding of what drives consumers' green buying behavior in different cultural settings.

• Journal of Practical Agriculture & Fisheries Research
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• v.21 no.2
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• pp.27-33
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• 2019

The purpose of this study was to compare the storage and post-storage changes of Cheorwon onions and onions for each region. Onion is a perennial plant belonging to the lily family. It is native to Persia of Southwest Asia. It is cultivated much in the temperate regions of the world. Cheorwon area is inland, but it has high continental climate due to its high altitude. Therefore it is said that the onion cultivated in this region has higher sugar content and higher taste than onion grown in southern region. Although the results of onion storage experiments in Cheorwon, Muan, Buan, and Changnyeong regions did not show much difference in weight, width, and height measurements before and after storage, Brix was reduced by approximately 1-2 brix. Before and after storing in each region, Brix was the highest in Cheorwon, Changnyeong, Buan, and Muan, and after saving, onions in Cheorwon were the same order. After each region was stored, the results showed that Cheorwon (112.3g), Muan (106g), Buan (102.1g) and Changnyeong (92.6g) had the highest hardness. Cold storage tests show that onions contain the least amount of corruption in paper boxes, while Cheorwon onions have the lowest level of corruption in other areas.

• Journal of Naturopathy
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• v.7 no.2
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• pp.51-62
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• 2018

Purpose: The purpose of this study was to investigate the changes of stress and cumulative stress in 49 people and the changes of job stress, socio-psychological stress and anxiety relief levels by conducting a survey of 85 people after Gyorae forest bathing. Methods: The level of stress was measured using the uBioMacpa, and questionnaire was conducted to derive the data. Results: In the stress level after the forest bath, the control group showed no significant and the experimental group showed a significant decrease in the bathing (p<.043). In the cumulative stress change, the control group showed no significant difference after the bathing, but experimental group decreased significantly (p<.02), and in the variance analysis, there was a significant difference between the groups, and also between the group and the before and after tests (p<.002). In the questionnaire about job stress, there was no significant difference in physical environment and job demand. Overall, in the case of job stress, there was a significant decrease (p<.001). Job autonomy, relationship conflict, organizational unfairness, inadequate compensation, and workplace culture also had a significant decrease in stress (p<.001). The social psychological stress was significantly decreased after bathing (p<.001). The state anxiety decreased significantly (p<.001) after forest bathing. Conclusions: After the forest bathing in the Gyorae forest, the stress and anxiety are both reduced and significant, providing basic information that is very helpful as a natural healing place for stress relief.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.355-363
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• 2023

In safety assessment of a aged bridge, dynamic characteristics and displacement are directly related to the rigidity of the structural system, especially displacement is the most important factor as the physical quantity that the bridge user can directly detect. However, in order to measure the displacement of the bridge, it is difficult to install displacement sensors at the bottom of the bridge and conduct traffic blocking and loading tests, resulting in increased costs or impossible measurements depending on the bridge's environment. In this study, a method of measuring the displacement of a bridge using only accelerometers without installing displacement sensors and ambient vibration without a loading test was proposed. For the analysis of bridge dynamic characteristics and displacement using ambient vibration, the mode shape and natural frequency of the bridge were extracted using a TDD technique known to enable quick analysis with simple calculations, and the unit load displacement of the bridge was analyzed through flexibility analysis to calculate static displacement. To verify this proposed technology, an on-site test was conducted on C Bridge, and the results were compared with the measured values of the loading test and the structural analysis data. As a result, it was confirmed that the mode shape and natural frequency were 0.42 to 1.13 % error ratio, and the maximum displacement at the main span was 3.58 % error ratio. Therefore, the proposed technology can be used as a basis data for indirectly determine the safety of the bridge by comparing the amount of displacement compared to the design and analysis values by estimating the displacement of the bridge that could not be measured due to the difficulty of installing displacement sensors.

• Journal of Aerospace System Engineering
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• v.18 no.1
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• pp.1-10
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• 2024

In a previous study, a structure of a superplastic yoke consisting of a thin FR4 layer laminated with viscoelastic tape on both sides of a shape memory alloy (SMA) was proposed to reduce residual vibration generated by a deployable solar panel during high motion of a satellite. Damping properties of viscoelastic tapes will change with temperature, which can directly affect vibration reduction performance of the yoke. To check damping performance of the yoke at different temperatures, free damping tests were performed under various temperature conditions to identify the temperature range where the damping performance was maximized. Based on above temperature test results, this paper predicts temperature of the yoke through orbital thermal analysis so that the yoke can have effective damping performance even if it is exposed to an orbital thermal environment. In addition, the thermal design method was described so that the yoke could have optimal vibration reduction performance.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.2
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• pp.106-111
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• 2008

Six standard methods for marine ecotoxicological tests were established(or applicated) using marine decomposer, primary producers and consumers. Development processes referred to the standard methods established by USEPA(United States Environmental Protection Agency), international organizations and European methods. However, the standard test species were selected among the domestic species generally found in the Korean waters and sediments. The test methods provide the culture/maintenance of test species, test methods, reproducibility and quality acceptance criteria etc. A total of nine test species were designated including bioluminescent bacteria(Vibrio fischeri), diatom(Skeletonema costatum), seaweed(Ulva pertusa), rotifer(Brachionus plicatilis), benthic copepod(Tigriopus japonicus), benthic amphipods(Mandibulophoxus mai, Monocorophium acherusicum), and fishes(Oryzias latipes, Paralichthys olivaceus). These test species represent the decomposer, primary producer and consumers in marine trophic system in Korean coastal ecosystems, and we recommend the "battery test" including at least one species from the each trophic level for marine ecotoxicological test.