• Journal of the Korea Society for Simulation
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• v.28 no.2
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• pp.35-48
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• 2019

Domestic hydraulic drifters till now have been developed by benchmarking products from overseas leading companies. However, they do not have excellent impact performance as they are not suitable for characteristics (large flow rate and low pressure) of Korean hydraulic drill power pack, and therefore, research on the optimum design has not made much headway. This study performs multi-objective function optimization for hydraulic drifters whose capacity has been redesigned to deal with the large flow rate, and also with the help of this function, it aims to improve impact power and reduce supply and surge pressure. A summary of the research study is as follows: First, we set goals for improving impact power, supply pressure, and surge pressure, and then perform multi-objective function optimization on them. After that, we secure the reliability of the optimized analytical model by comparing the test results of the prototype built by the optimized design with the analysis results of the analytical model. This study used SimulationX, that is the hydraulic system analysis software, and EasyDesign, which is a multi-objective function optimization program. Through this research, we have achieved the results that satisfy the goal of developing high power drifters suitable for Korean type hydraulic drills.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.3
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• pp.1-9
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• 2019

In the recent marine sector, the development and standardization regarding S-100, which is the universal hydrographical data model standard for development of marine space information, was progressed, and for the effectiveness of marine chart production work and the multi-purpose use of water level data in S-100, S-102(Bathymetric Surface grid) standard development and various studies of BAG formats combined with water level and uncertainty, property information is being progressed. Since the water level information that is important in the operation of the ship is provided based on S-102, the calibration method of the location information when producing S-102 is an important factor in deciding the water level. In this study, the hydrographical surveying was conducted by piloting the standardized method for the production of S-102 in Korea, and have compared the accuracy of water level information according to the GNSS post treatment calibration method. As a result of comparing the water level in 2 places in the rocky terrain of the study area, the northern water level of Namu-do was shown as DL 0.79~0.83m, the eastern water level of Daeho-do was DL 12.63~12.91m, and the horizontal position errors of the intermittent sunshine water level were confirmed to be within 1m. As a result, the intermittent sunshine water level according to the location calibration method when producing the BAG was confirmed that it was in the available range for a ship's safe voyage. However, the accuracy verification for the location of the ship when conducting hydrographical surveying was judged that there is a need for a various additional study about regional characteristics and environment factor.

• Tunnel and Underground Space
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• v.29 no.3
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• pp.184-196
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• 2019

This study aims to extract a 3D image of micro-cracks generated by hydraulic fracturing tests, using the deep learning method and X-ray computed tomography images. The pixel-level cracks are difficult to be detected via conventional image processing methods, such as global thresholding, canny edge detection, and the region growing method. Thus, the convolutional neural network-based encoder-decoder network is adapted to extract and analyze the micro-crack quantitatively. The number of training data can be acquired by dividing, rotating, and flipping images and the optimum combination for the image augmentation method is verified. Application of the optimal image augmentation method shows enhanced performance for not only the validation dataset but also the test dataset. In addition, the influence of the original number of training data to the performance of the deep learning-based neural network is confirmed, and it leads to succeed the pixel-level crack detection.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.3
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• pp.111-127
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• 2019

The "fourth industrial revolution" is changing society as a whole. Public innovation is needed to enhance national competitiveness. Amid these times' demands, the "maker movement," a new form of DIY movement that has revived since 2000, is regarded as a "popular innovation activity" that can respond to changing needs. In particular, "Makerspace," a significant activity area for the maker's movement, is drawing attention as a place where "Maker" shares each other's knowledge and resources, and share results. Makerspace has recently expanded its functions into a 'public innovation platform' or (preparation) start-up preparation space for start-ups. South Korea has also supported various types of "Makerspace" since 2010 as a policy for fostering an innovation base. The Ministry of Small and Medium Venture Business has been pushing for expansion of Makerspace since 2018 and is providing support by dividing it into "general rap" and "professional wrap" and "zero to Maker" spaces for novice makers in the beginning and necessary stages of makers, while "professional rap" is divided into "Maker to Maker" spaces for professionals. This study is about Makerspace, space where makers are active among the topics related to manufacturers. Thus, in this study, significant domestic and international studies related to Makerspace have been investigated so far, and trends in related studies have analyzed. Based on this, the research needs and specifics of Makerspace, which has recently expanded its role and functions. In particular, the Commission intends to present the need for research on Makerspace and specific areas of study from a start-up management perspective to promote qualitative growth of Makerspace, which is changing into a popular innovation platform in the era of the fourth industry, and inducing a start-up management interest in new manufacturing industry types.

• The Journal of the Korea Contents Association
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• v.19 no.2
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• pp.650-660
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• 2019

The purpose of this study is to verify the effect of the contents of tooth extraction education using VR(virtual reality) on knowledge, performance and satisfaction of practicing teeth. To accomplish this purpose, we divided 72 dental students into the two groups: The experimental group 30 dental students using VR based tooth extraction training contents. And the control group consisted of 42 participants. As a first result for the study, The experimental group using VR tooth extraction content and control group receiving the training using the tooth model based content showed no statistically significant difference in tooth extraction knowledge. Second, in the case of performance of tooth extraction (before tooth extraction-tooth extraction-after tooth extraction-finishing), the training group using VR tooth extraction contents was higher than the control group. Third, The satisfaction rate of the practice group using VR tooth extraction education contents was higher than in the control group. Therefore, it can be seen that the practical training using the VR applied tooth extraction contents improves the performance of the tooth extraction and the satisfaction of the practice more than the existing practice method.

• Korean Journal of Construction Engineering and Management
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• v.20 no.1
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• pp.96-104
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• 2019

Recently, projects are being actively promoted to develop a new residential district centered around the metropolitan area, or to redevelop the residential area that was established long ago as unplanned land development. In this residential area, the owner can directly construct the building, and the way the building owner builds the residential house is called the direct construction of the owner. If the owner has the construction management (CM) capability while conducting direct management of the owner, the direct construction can be carried out by the CM method. This type of construction is called Owner-CM delivery method. However, it is very rare for small-scale construction in Korea to be implemented by the Owner-CM method. This may be due to the lack of knowledge and experience about the CM of the owner. In this study, we investigated the actual cases of the scheduling for the residential houses of similar size which were built at the same time in the residential housing complex developed near the metropolitan area. The purpose of this study is to derive the success factors of the scheduling in the small-scale construction from the cases carried out by the Owner-CM method. These success factors of the scheduling can be used as meaningful reference for the owners who want to build their own house in the future.

• Journal of Convergence for Information Technology
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• v.9 no.3
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• pp.112-119
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• 2019

This study examined the role of citizen advocates in advocating for people with developmental disabilities. Citizen advocacy refers to activities that advocate and represent citizens on behalf of those who are socially vulnerable. The purpose of this study is to analyze the role concept of citizen advocates by conducting focus group interviews and dividing the 13 citizen advocates with developmental disabilities into 4 groups. It is divided into four main subjects and nine sub-themes. The main theme are 'Self-transformation of the parties', 'Restoring the rights of the parties', 'Being with the parties', and 'Expanding the world of the parties'. Sub-themes are 'Recognizing and solving the problem of self', 'Granting role to speak', 'Recovering the initiative of service use', 'Restoring the rights of existing (family and neighbor), "Preventing money harm" "Speaking instead", "Encouraging and petting people", "Promoting change in the community", and "Expanding the size of the world a little bit". Based on this, we discussed the importance of citizen advocacy as a preventive advocacy system, the relationship between citizen advocacy and professional advocacy system, the difference between volunteer and personal assistants and citizen advocacy, and considerations for citizen advocacy.

• Journal of Convergence for Information Technology
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• v.9 no.3
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• pp.104-111
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• 2019

The purpose of this study is to know the change of brain wave with stress by SUKI pressure alternative therapy. The experiment group was 12 students(male 6/female 6) with complained upper trapezius pain. Calculated the brain wave before and after stimulate the upper trapezius trigger point by SUKI and the stimulate time was 3min each persons(FP2, F3, F4, FP1, T3, T4, P3, P4). the experimet periods was 5times in a weeks with EEG(QEEG-S). The Date collecting used by Telescan(LXE5209). All the data was analyzed with SPSS 22.0 for window program. To compare the differences before and after the point pressure method, a corresponding sample of t-test was performed, and the statistical significance level was p<.05. The results was followed. The points of Fp2, F3, F4(*p<0.049, *p<0.042, *p<0.019) of EEG was showed a significant differences but Fp1, T3, T4, P3, P4 points did not showed. The SUKI alternative medicine techniques had a reduced effects for the some kind of brain stress. It is need to continuous research in the future.

• Korean Journal of Construction Engineering and Management
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• v.20 no.1
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• pp.14-21
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• 2019

The construction phase of the construction project needs a large scale of manpower, materials and equipment. Among them, manpower is a core part for project construction. These manpower are divided into two groups. The first is the management group that manages the construction, and the second is the site technician manpower for construction work. Recently, construction company has suffering due to the insufficient supply of technician labor. Accordingly, this study will perform an empirical analysis about the construction technician. To do this, we surveyed related research trends and conducted surveys on the satisfaction of the construction technician. The result, satisfaction with pay and insurance was relatively low compared to other items. Therefore, this study were conducted in-depth interviews with technician managers in order to analyze the cause. In addition, case analysis was conducted to analyze actual working conditions. As a result, it was analyzed that the wage level and insurance system of construction technician were considerably stable compared to the manufacturing industry. The result of this study is expected to contribute to the activation of excellent technician cultivation through the change of recognition about construction technician.

• Journal of Food Hygiene and Safety
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• v.34 no.1
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• pp.73-86
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• 2019

Seafaring is an important occupation that requires stringent hand hygiene practices as a basic method for preventing food-borne illness and infectious diseases when the diseases occur on board. The purpose of this study is to provide fundamental data for the prevention of food-borne illness and infectious disease on the ship by investigating the level of hand hygiene practices and influencing factors. A total of 222 seafarers were surveyed at a seafarers' educational institution between July and August 2017. Their hand hygiene practice were examined by a modified method using the guidelines which are recommended by the World Health Organization, the Centers for Disease Control and Prevention, and Hand Hygiene Australia. The mean of hand hygiene practice was 47.97 out of 75 points. By category, the most frequent hand hygiene practice was measured as 4.04 on a 5-point scale as 'after working'. Factors affecting hand hygiene practices were ship tonnage relating to in job characteristics, exercise in health-related characteristics, and soap in relation to the characteristics of the hand hygiene environment on board. To improve hand hygiene among seafarers, it is necessary to raise awareness of hand hygiene among seafarers who work on small ships in particular, and to improve the systems of hand hygiene on ships with continuous education, hygiene practice evaluation and feedback.