• Journal of Technologic Dentistry
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• v.39 no.3
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• pp.171-177
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• 2017

Purpose: The purpose of the study is to analyze the effects that Flipped Learning Method has on a college student's self directed learning ability, critical thinking disposition, learning motivation, and learning satisfaction, and determine its effectiveness as a new pedagogical approach. Methods: The survey was conducted on dental technology students. The collected data was analyzed by the statistical program SPSS 21.0. The results were analyzed by reliability, frequency, t-test. To test for significance on each item, p<0.05 has been decided as a standard. Results: According to the analysis, the student who attended a class that utilized Flipped Learning Method was found to have higher levels of self directed learning ability, critical thinking disposition, learning motivation, and learning satisfaction than a student who attended a class that did not utilize such a method. Conclusion: The study results show that, in order to enhance students' self directed learning ability, critical thinking disposition, learning motivation, and learning satisfaction and to improve the quality of class instruction, it may be necessary that Flipped Learning Method be adopted more widely and recommended more strongly. Such changes will promote a long term improvement in educational environments and play a major role in strengthening students' abilities.

• International Journal of Fluid Machinery and Systems
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• v.9 no.1
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• pp.39-46
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• 2016

A high frequency hydraulic rock drill drifter with sleeve valve is developed to use on arm of excavator. In order to ensure optimal working parameters of impact system for the new hydraulic rock drill drifter controlled by sleeve valve, the performance test system is built using the arm and the hydraulic source of excavator. The evaluation indexes are gained through measurement of working pressure, supply oil flow and stress wave. The relations of working parameters to impact system performance are analyzed. The result demonstrates that the maximum impact energy of the drill drifter is 98.34J with impact frequency of 71HZ. Optimal pressure of YZ45 rock drill is 12.8 MPa-13.6MPa, in which the energy efficiency reaches above 58.6%, and feature moment of energy distribution is more than 0.650.

• Smart Structures and Systems
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• v.24 no.4
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• pp.459-474
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• 2019

This study develops a novel recursive algorithm to significantly enhance the computation efficiency of a recently proposed stochastic subspace identification (SSI) methodology based on an alternative stabilization diagram. Exemplified by the measurements taken from the two investigated office buildings, it is first demonstrated that merely one sixth of computation time and one fifth of computer memory are required with the new recursive algorithm. Such a progress would enable the realization of on-line and almost real-time monitoring for these two steel framed structures. This recursive SSI algorithm is further applied to analyze 20 months of monitoring data and comprehensively assess the environmental effects. It is certified that the root-mean-square (RMS) response can be utilized as an excellent index to represent most of the environmental effects and its variation strongly correlates with that of the modal frequency. More detailed examination by comparing the monthly correlation coefficient discloses that larger variations in modal frequency induced by greater RMS responses would typically lead to a higher correlation.

• Advances in materials Research
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• v.11 no.2
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• pp.165-170
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• 2022

Acrylic resin or polymethylmethacrylate (PMMA) is one of the most attractive materials to be used for dental appliances manufacturing. It has been introduced as a biomaterial during the last century. This study aims to evaluate the compounds absorption and release through acrylic resin to be used for drug delivery as well. The study specimens were 10 pieces of heat-cured clear acrylic resin with dimensions of 10 × 10 × 2 mm. The specimens were dipped in methylene blue solution at a powder-water ratio of 1:20 for 5 days. The samples were removed and dipped in 5 ml distilled water vials for 24 hours. Then the specimens were replaced into new 5 ml vials and the process lasted for 4 days. The extracted solutions were analyzed by the visible light spectroscopy for absorbance. The statistical results showed a gradual increase in stain release from day 1 to day 4 with a significant difference between day 1 and day 4 solutions. The study showed that PMMA resin is able to absorb and release some compounds constantly and the absorption drug-loading technique is applicable to this material.

• Journal of Korean society of Dental Hygiene
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• v.19 no.5
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• pp.803-811
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• 2019

Objectives: This study investigated the factors influencing organizational socialization of new dental hygienists and provides basic data for successful organizational socialization. Methods: Data were collected using self-report questionnaires from 199 new dental hygienists of dental clinic and hospital between June and September 2018. Data analysis using SPSS 22.0 included Independent t-test, one way ANOVA, Scheffe post-hoc test, Pearson correlation coefficients, and multiple regression analysis. Results: The new dental hygienists' professional self-concept, interpersonal ability, and organizational socialization value were $3.27{\pm}0.50$, $3.55{\pm}0.45$, and $3.03{\pm}0.37$, respectively. There were significant positive correlations between professional self-concepts, interpersonal relations, and organizational socialization. A positive correlation was found between professional self-concept and interpersonal relations. Factors affecting organizational socialization of new dental hygienists included the strength of work, interpersonal relations, and professional self-concept. Professional self-concept was the most influential factor leading to 54.7% of the variance in organizational socialization. Conclusions: Therefore, to improve the organizational socialization of new dental hygienists and reduce the turnover rate, it is necessary to develop and implement programs promoting professional self-concept and interpersonal relations.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.2
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• pp.128-137
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• 2021

Objectives: The purpose of this study is to propose a smart work environment management service model that can measure and maintain work environments in real time. Methods: How existing private consignment business is being carried out was identified and a simpler method was applied to the model. Results: Common support was provided according to the Korea Standard Industrial Classification. Hazards suitable for the relevant industry classification were selected and information on safety and health education, etc. was provided. Theme-specific support provides services focusing on hazards that can be measured through applications. Hazards are evaluated by applying new standards divided into 'Good', 'Average', 'Inadequate', and 'Faulty'. Conclusions: This model is designed to help employers identify health and safety conditions in small businesses where it is difficult to hire health and safety professionals. Using the app proposed in this study, anyone can easily measure their work environment at any time.

• Safety and Health at Work
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• v.12 no.1
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• pp.42-50
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• 2021

Introduction: Despite huge investments in new technology and transportation infrastructure, terrible accidents still remain a reality of traffic. Methods: Severe traffic accidents were analyzed from four prevailing modes of today's transportations: sea, air, railway, and road. Main root causes of all four accidents were defined with implementation of the approach, based on Flanagan's critical incident technique. In accordance with Molan's Availability Humanization model (AH model), possible preventive or humanization interventions were defined with the focus on technology, environment, organization, and human factors. Results: According to our analyses, there are significant similarities between accidents. Root causes of accidents, human behavioral patterns, and possible humanization measures were presented with rooted graphs. It is possible to create a generalized model graph, which is similar to rooted graphs, for identification of possible humanization measures, intended to prevent similar accidents in the future. Majority of proposed humanization interventions are focused on organization. Organizational interventions are effective in assurance of adequate and safe behavior. Conclusions: Formalization of root cause analysis with rooted graphs in a model offers possibility for implementation of presented methods in analysis of particular events. Implementation of proposed humanization measures in a particular analyzed situation is the basis for creation of safety culture.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.96-110
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• 2021

Korea is faced with the challenge of adapting to the world's fastest - growing low birthrate, aging society, and low growth with low interest rate era. With low fertility and aging population, the factors of financial income of health insurance are decreasing, and the increase of public interest in health, high cost medical technology and the development of medicine are leading to increase expenditure of health insurance. In this study, I will examine the strengthen protection of health insurance, financial stabilization, and fairness of medical care. First, the present status and limitations of health insurance were identified through domestic policy report, domestic and foreign literature, and precedent research. Second, the foreign health insurance policy measures to stabilize the finances were examined separately. Based on this study, in order to maintain sustainable health insurance through reinforcement and financial stabilization of health insurance, the current financial income structure of health insurance must be renovated. It will be necessary to expand government subsidies and discover new tax revenues. In addition, a policy to save finances by reorganizing the medical bill payment system and medical delivery system will also be needed.

• Journal of dental hygiene science
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• v.9 no.2
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• pp.189-195
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• 2009

Two diketones, 1,2-phenylpropanedione (PD) and diacetyl (DA) were investigated as new visible light photosensitizers for dental composite resin of bis-GMA in order to improve the photopolymerization effect. The photopolymerization efficiency of bis-GMA composite resin containing PD and DA was studied by IR absorption spectroscopy. And the results were compared with that of camphorquinone (CQ). Relative photopolymerization efficiency of the photosensitizers increased in the order of DA < CQ < PD. Thus. PO is a new visible light photosensitizer for dental composite resin with higher photopolymerization efficiency than that of CQ.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.856-860
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• 2000

Cloning technology continues to capture widespread attention by the international news media and biomedical and agricultural industries. The future uses of this technology could potentially contribute to major advances in biomedical and agricultural sciences. Cloned transgenic dairy cattle possessing milk promoters directing transgenes will produce pharmaceutical proteins in their milk faster, more efficiently and less expensively than transgenic cattle created using microinjection techniques. Additionally, cloned transgenic fetuses and animals may become a source of cells, tissue and organs for xenotransplantation. Lastly, but maybe most importantly, enhanced production traits and disease resistance may be realized in animal agriculture by utilizing these new technologies. The recent advances in the cattle cloning technology are important but there are still major obstacles preventing widespread commercial use of this technology. The type of donor nucleus, recipient cytoplasm, and cloning procedures used will impact the potential number of clones produced and the uses of the technology. In addition, the new advances in cloning methodology have not improved the relatively low pregnancy rates or reduced the incidence of health problems observed in cloned offspring. These problems may require novel techniques to decipher their cause and new methods of preventing and/or diagnosing them in the preimplantation embryo. The commercial potential is enormous for cloning technology; however, little has been done to improve the efficiencies of the procedure. Improving procedural efficiencies is a critical developmental milestone especially for potential uses of cloning technology in animal agriculture.