• The Journal of Korean Academy of Prosthodontics
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• v.45 no.6
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• pp.717-723
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• 2007

Statement of problem. Unreasonable distal cantilevered implant-supported prosthesis can mask functional problems of reconstruction temporarily, but it can cause serious strain and stress around its supported implant and surrounding alveolar bone. Purpose. The purpose of this study was to evaluate strain of implants supporting distal cantilevered fixed prosthesis with two different cantilevered length under distal cantilevered static load. Material and methods. A partially edentulous mandibular test model was fabricated with auto-polymerizing resin (POLYUROCK; Metalor technologies, Stuttgart, Swiss) and artificial denture teeth (Endura; Shofu inc., Kyoto, Japan). Two implants-supported 5-unit screw-retained cantilevered fixed prosthesis was made using standard methods with Type III gold alloy (Harmony C&B55; Ivoclar-vivadent, Liechtenstein, Germany) for superstructure and reinforced hard resin (Tescera; Ivoclar-vivadent, Liechtenstein, Germany) for occlusal material. Two strain gauges (KFG-1-120-C1-11L1M2R; KYOWA electronic instruments, Tokyo, Japan) were then attached to the mesial and the distal surface of each standard abutment with adhesive (M-bond 200; Tokuyama, Tokyo, Japan). Total four strain gauges were attached to test model and connected to dynamic signal conditioning strain amplifier (CTA1000; Curiotech inc., Paju, Korea). The stepped $20{\sim}100$ N in 25 N increments, cantilevered static load 8mm apart (Group I) or 16mm apart (Group II), were applied using digital push-pull gauge (Push-Pull Scale & Digital Force Gauge, Axis inc., Seoul, Korea). Each step was performed ten times and every strain signal was monitored and recorded. Results. In case of Group I, the strain values were surveyed by $80.7{\sim}353.8{\mu}m$ in Ch1, $7.5{\sim}47.9{\mu}m/m$ in Ch2, $45.7{\sim}278.6{\mu}m/m$ in Ch3 and $-212.2{\sim}718.7{\mu}m/m$ in Ch4 depending on increasing cantilevered static load. On the other hand, the strain values of Group II were surveyed by $149.9{\sim}612.8{\mu}m/m$ in Ch1, $26.0{\sim}168.5{\mu}m/m$ in Ch2, $114.3{\sim}632.3{\mu}m/m$ in Ch3, and $-323.2{\sim}-894.7{\mu}m/m$ in Ch4. Conclusion. A comparative statistical analysis using paired sample t-test about Group I Vs Group II under distal cantilevered load shows that there are statistical significant differences for all 4 channels (P<0.05).

• Geophysics and Geophysical Exploration
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• v.11 no.2
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• pp.153-160
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• 2008

Seismic modeling is used to simulate wave propagation in the earth. Although the earth's subsurface is usually semi-infinite, we cannot handle the semi-infinite model in seismic modeling because of limited computational resources. For this reason, we usually assume a finite-sized model in seismic modeling. In that case, we need to eliminate the edge reflections arising from the artificial boundaries introducing a proper boundary condition. In this study, we changed three kinds of boundary conditions (sponge boundary condition, Clayton and Engquist's absorbing boundary condition, and Higdon's transparent boundary condition) so that they can be applied in elastic wave modeling for anisotropic media. We then apply them to several models whose Poisson's ratios are different. Clayton and Engquist's absorbing boundary condition is unstable in both isotropic and anisotropic media, when Poisson's ratio is large. This indicates that the absorbing boundary condition can be applied in anisotropic media restrictively. Although the sponge boundary condition yields good results for both isotropic and anisotropic media, it requires too much computational memory and time. On the other hand, Higdon's transparent boundary condition is not only inexpensive, but also reduce reflections over a wide range of incident angles. We think that Higdon's transparent boundary condition can be a method of choice for anisotropic media, where Poisson's ratio is large.

• Child Health Nursing Research
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• v.3 no.2
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• pp.228-240
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• 1997

It is important to asess the risk factors of parenting and provide early intervention for promotion of the maternal caretaking ability. The purpose of the study was to identify the maternal burden of caretaking, the supporting and the educational need for the caretaking activities of the mother of infant. Sixty three mothers of infants who visited the wellbaby clinic of S university hospital and one health center during the period of November 1st, to 30th in 1996 comprised the subjects of this study, Data were gathered through the instruments that were developed by researcher. Statistical analysis of this study was used ANOVA and Pearson correlation. The results were as follows : 1) The mean score of the maternal burden of caretaking was 22.06. The maternal burden of caretaking was significantly high in the mothers who had vaginal delivery compare with the mothers who had caeserean section and in the muthers who gave artificial feeding compare with the group of breast or mixed feeding. 2) The mean score of the support need for the caretaking activities was 30.69. The support need for the caretaking activities was significantly high in the mothers who had the second child, compare with the mothers who had first or third child. And the support need for the caretaking activities was significantly high in the mothers who had caretaking help compare with the mothers who had no caretaking help. The specific subjects of 'mother-infant interaction', 'immunization' and 'prevention of accident' on the support need for the caretaking activities were relatively high. 3) The mean score of the educational need of caretaking activities was 29.3. The educational need of caretaking activities was significantly high in the mother who had the second child compare with the mothers who had first or third child. And the educational need of caretaking activities was significantly high in the mothers who had caretaking help compare with the mothers who had no caretaking help. The specific subjects of 'mother-infant interaction', 'emergency care' and 'prevention of accident' on educational need of caretaking were relatively high. 4) The maternal burden of caretaking was not correlated with the support need or the educational need of caretaking activities. But the support need of caretaking activities was significantly correlated with the educational need of caretaking activities. 5) The support and educational need of caretaking activities were significantly high in the mothers who wanted home care for caretaking their infants. Through the study, it was found that there is considerable maternal burden of caretaking as well as the support and educational need on the caretaking activities in the mothers whose child is young. Therefore developing the systematic and effective program is needed to meet the mother's need. The results of this study will be useful resources to develop the program. On the other hand, it can be recommanded that home health care will be one of the approach to support the mothers caretaking activities.

• The Journal of Engineering Geology
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• v.18 no.2
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• pp.127-136
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• 2008

Geophysical survey for establishing a wide site for the distribution of water content, wetting front infiltration due to the rainfall, and distribution of groundwater level has been performed by using 8round penetration radar (GPR) method, electrical resistivity method, and so on. On the other hand, a narrow area survey was performed to use a permittivity method such as time domain reflectometry, frequency domain reflectometry, and amplitude domain reflectometry methods for estimating volumetric water content, soil density, and concentration of contaminant in surface and subsurface. The permittivity methods establish more corrective physical parameters than different found survey technologies mentioned above. In this study for establishment of infiltration behaviors for wetting front in the unsaturated soil caused by an artificial rainfall, soil physical parameters for volumetric water content, pore water pressure, and pore air pressure were measured by FDR measurement device and pore water pressure meter which are installed in the unsaturated weathered granite soil with different depths. Consequently, the authors were proposed to a new establishment method for analyzing the variations of volumetric water content and wetting front infiltration from the responses of infiltrating pore water in the unsaturated soil.

• Journal of the Mineralogical Society of Korea
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• v.23 no.1
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• pp.63-71
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• 2010

The artificial rains having different pH and weathering simulation test were performed for Gyeongju Namsan granite and dacitic tuff to predict the role of acid rain in the deterioration of stone monuments located in Gyeongju area. The pH 4.0 rain reacted with the fresh granite showed near neutral pH at the early stage due to the hydrolysis of minerals in the rock surface. But the pH changed back to the initial pH in the later stage. On the other hand, the pH 5.6 rain showed the neutral pH for a longer time than the experiment with pH 4.0 rain, reflecting slower reaction of minerals due to the weaker acidity. When the pH 5.6 rain reacted with the weathered granite, the water showed neutral pH longer than the case of the fresh granite. The similar tendencies were observed in the experiment of dacitic tuff, except that the pH 4.0 rain reacted with dacitic tuff took a longer time to go back to the initial pH as compared with the case of granite. These results may due to the differences in mineral composition and texture of two rocks. Dacitic tuff contains more fine-grained or glassy groundmass than granite and is more reactive with weaker acid rain. It was predicted that the weight loss and strength decrease rate of dacitic tuff would be approximatetly twice relative to those of granite in the same experimental environment.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.8
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• pp.359-368
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• 2017

What is the term "intelligence information society", which is a term that has been continuously discussed recently? This means that the automation beyond the limits of human ability in the whole societies based on intelligent information technology is a universalized social future. In particular, it is a concept that minimizes human intervention and continuously pursues evolution to data (or big data) -based automation. For example, autonomous automation is constantly aiming at unmanned vehicles with artificial intelligence as a key element. However, until now, intelligent information research has focused on the intelligence itself and has made an effort to improve intelligence logic and replace human brain and intelligence. On the other hand, in order to replace the human labor force, we have continued to make efforts to replace workers with robots by analyzing the working principles of workers and developing optimized simple logic. This study proposes important strategies and directions to implement intelligent information education policy and intelligent information technology research strategy by suggesting access strategy, education method and detailed policy road map for intelligent information technology research strategy and educational service. In particular, we propose a phased approach to intelligent information education such as basic intelligence education, intelligent content education, and intelligent application education. In addition, we propose education policy plan for the improvement of intelligent information technology, intelligent education contents, and intelligent education system as an important factor for success and failure of the 4th industrial revolution, which is centered on intelligence and automation.

• Resources Recycling
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• v.26 no.4
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• pp.42-49
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• 2017

As a fundamental study for the separation of vanadium and tungsten from the leaching solution obtained from the soda roasting and water leaching process of spent SCR (Selective Catalytic Reduction) catalyst was carried out. The precipitation behaviors of vanadium and tungsten using the artificial solution (V: $1g{\cdot}L^{-1}$, W: $10g{\cdot}L^{-1}$) was investigated depending on temperature, NaOH concentration and the amount of $CaCl_2$ (aq.) added. V (aq.) was selectively precipitated at lower temperature than 293 K while tungsten also was precipitated at higher temperature. Precipitation rate of V and W was decreased by the increasing concentration of NaOH. On the other hand, excess Ca addition induced the increase of precipitation rate for V and W due to the formation of $Ca(OH)_2$ following the pH decline. The response surface methodology was employed to optimize the selective precipitation. Vanadium of 99.5% and tungsten of 0.0% was precipitated at $0.5mol{\cdot}L^{-1}$ of aqueous NaOH and 1 equivalent ratio of $CaCl_2$ at 293 K.

• Cross-Cultural Studies
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• v.27
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• pp.59-79
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• 2012

China and Japan are geographically close and the two countries had shared the Chinese Character Culture and the thoughts of Confucianism, Buddhism and Taoism since the ancient age. They also actively exchanged culture in various areas. Some cultural exchanges had been caused by surrounding environment and culture had been introduced to other country in a natural way; while some cultural exchanges had been forcibly introduced through artificial process. It is believed that such cultural phenomenon must have had impact on the make-up cultures of the two countries and it was assumed that there must have been commons and differences in the make-up cultures of the two countries. This study explored the historical background of the Ching dynasty of China and the Edo Age in Japan, which are in the same time frame, and studied the aesthetic consciousness of the two countries at the time. Then the make-up style of ladies in the two countries had been studied to find out how their aesthetic consciousnesses had been expressed in the make-ups of the two countries. Then the commons and differences in make-up skills between the two countries had been identified. According to the study results, the main stream of aesthetics during the Ching dynasty in China can be classified into Confucianism aesthetics and Taoism aesthetics. On the other hand, the main stream of aesthetics during the Edo Age in Japan can be classified into "mitate(見立)", "ikki(いき)" and "garumi(かるみ). The skin care in the make-up culture of Ching dynasty in China was based on "rouge (?脂, yanzhi)" and "powder(粉, fen)". The Ching ladies loved the make-up style using rouge. It had been same both in the high society and common people. The eyebrow care was delicate and curved so that the feminine beauty with elegant spirit could be emphasized. The lips had been expressed to be smaller and the ladies tried to express elegance and reliability, rather than frail and tender feminine image. The skin care in the make-up culture of Edo Age in Japan focused on even applying of white powder so that the face would look soft. The eyebrow make-up was a very important part of the make-up. The shapes of eyebrow had been advanced in various styles and there had been eyebrow make-up styles such as "crescent-shaped brow (三日月), "crane style brow (鶴眉) and "Tang style brow (唐眉). The lips had been applied of thick red color, imitating the make-up skill of the ladies in the entertainment business. The lips make-up skill expressing the lips in two colors had been quite popular. Among the make-up skills during the Edo Age in Japan, the "black teeth (齒黑)" can be said as the most unique make-up style of Edo Age.

• Journal of Science Education
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• v.45 no.2
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• pp.156-171
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• 2021

This study aims at investigating the characteristics of trends of future education over time though the literature review and examining the accuracy of the framework for forecasting future education proposed by the previous studies by comparing the outcomes between the literature review and media articles. Thus, this study collects the articles dealing with future education searched from the Web of Science and categorized them into four periods during the new millennium. The new articles from media were selected to find out the present of education so that we can figure out the appropriateness of the proposed framework to predict the future of education. Research findings reveal that gradual tendencies of topics could not be found except teacher education and they are diverse from characteristics of agents (students and teachers) to the curriculum and pedagogical strategies. On the other hand, the results of analysis on the media articles focuses more on the projects launched by the government and the immediate responses to the COVID-19, as well as educational technologies related to big data and artificial intelligence. It is surprising that only a few key words are occupied in the latest articles from the literature review and many of them have not been discussed before. This indicates that the predictive framework is not effective to establish the long-term plan for education due to the uncertainty of educational environment, and thus this study will give some implications for developing the model to forecast the future of education.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.131-142
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• 2019

The primary objective of this study was to determine the content of biogenic amines in Korean traditional fermented soybean pastes (doenjang) and to isolate potential probiotic Bacillus sp. with the ability to inhibit biogenic amines accumulation. There were significant differences in the bacterial cell counts, pH value, titratable acidity, salinity, and biogenic amine content between the samples. Among Bacillus strains isolated from doenjang, Bacillus (B.) licheniformis DB102, B. subtilis DB203, B. stearothermophilus DB206, Bacillus sp. DB209, Bacillus sp. DB310, B. coagulans DB311, B. cereus DB313, B. amyloliquefaciens DB714, Bacillus sp. DB917, B. cereus DB 915, B. subtilis DB1020, and Bacillus sp. DB1022 were found to be able to produce biogenic amines. On the other hand, biogenic amine-degrading strains were identified as Bacillus sp. DB403, Bacillus sp. DB407, B. subtilis DB517, B. licheniformis DB612, and B. subtilis DB821. In particular, Bacillus sp. DB407 and B. subtilis DB821 showed probiotic properties including tolerance to artificial digestive juices, adherence to intestinal epithelial cells, resistance to antibiotics, and antibacterial activity against biogenic amine-producing strains. In conclusion, the two probiotic Bacillus strains may be considered as the suitable starter for manufacture of fermented soybean foods with low biogenic amines content.