• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.spc1
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• pp.132-141
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• 2006

Artificial structures have been designed as pilot structures to promote the creation and restoration of tidal flats. However, little information is available as to whether such artificial construction affects the macrobenthic community structure. We monitored the variation of the macrobenthic community structure and species composition near natural and artificial structures (seaweed and a timber fence) on the tidal flats near the Iwon Dike, Korea. In total, 137 macrobenthic species were recorded during this study, predominantly crustaceans (47%), polychaetes (18%), and molluscs (27%). Polychaetes comprised over 50% of the total density, followed by gastropods (38%) and crustaceans (11%). Macrobenthic species composition in the artificial and natural areas, was initially similar, but it differed after 7 months. The gastropod Umbonium thomasi, the most dominant species, was present at both sites in the first month after the start of the experiment, but disappeared at the artificial sites within 7 months, suggesting disturbance by the environmental factors. The number of species and diversity (H') varied significantly within sites at the beginning of the experiment, but no difference was observed after 7 months. Multivariate analysis (multidimensional scaling) revealed significant differences in community structure between the artificial and the natural areas from 7 months after the start of the experiment, except from 18 to 21 months. The community structures were mainly influenced by U. thomasi. Community structure at the artificial sites was affected by environmental variables, such as carbon, COD/IL sulfide, loss of ignition, kurtosis and silt, which changed over time. We observed no significant correlations between environmental variables and the dominant species, except in the case of Spio sp. and Macrophthalmus dilatatus, suggesting that the biological interactions and temporary disturbances such as typhoon, as well as the effects of artificial structures may also be important regulating factors in this system.

• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.66-78
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• 2011

It is getting difficult to manage water resources in South Korea because more than half of annual precipitation is concentrated in the summer season and its intensity is increasing due to global warming and climate change. Artificial recharge schemes such as well recharge of surface water and roof-top rainwater harvesting can be a useful method to manage water resources in Korea. In this study, potential artificial recharge site is evaluated using geographic information system with hydrogeological and social factors. The hydrogeological factors include annual precipitation, geological classification based on geological map, specific capacity and depth to water level of national groundwater monitoring wells. These factors were selected to evaluate potential artificial recharge site because annual precipitation is closely related to source water availability for artificial recharge, geological features and specific capacity are related to injection capacity and depth to water is related to storage capacity of the subsurface medium. In addition to those hydrogeological factors, social aspect was taken into consideration by selecting the areas that is not serviced by national water works and have been suffered from drought. These factors are graded into five rates and integrated together in the GIS system resulting in spatial distribution of artificial recharge potential. Cheongsong, Yeongdeok in Gyeongsangbuk-do and Hadong in Gyeongsangnam-do, and Suncheon in Jeollanam-do were proven as favorable areas for applying artificial recharge schemes. Although the potential map for artificial recharge in South Korea developed in this study need to be improved by using other scientific factors such as evaporation and topographical features, and other social factors such as water-curtain cultivation area, hot spring resorts and industrial area where groundwater level is severely lowered, it can be used in a rough site-selection, preliminary and/or feasibility study for artificial recharge.

• Restorative Dentistry and Endodontics
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• v.17 no.2
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• pp.383-397
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• 1992

The purpose of this study was to evaluate the influence of artificial saliva contamination on bonding of several dentin adhesives to dentin. Sixty - three human molar teeth extracted within a month were used. Each tooth was sectioned longitudinally in a buccolingual direction to obtain 126 specimens. These specimens were randomly divided into three groups and were treated by Scotchbond 2, Gluma and All bond. Each group was subdivided into three subgroups; normal group not contaminated with artificial saliva, contaminated with artificial saliva and dried group, and contaminated with artificial saliva and washed and dried group. Enamel/dentin bonding agent(Dental Adhesive of Scotchbond 2) was applied and light cured on the treated dentin surfaces. Thereafter P - 50 were cured on them, and specimens were stored in $37^{\circ}C$ artificial saliva for 24 hours before measuring shear bond strength. Shear bond strengths were determined using an universal testing machine with cross head speed 1mm/min and SEM examinations were conducted to evaluate the resin - dentin interface and degree of penetrating resin string into the dentinal tubules. The following results were obtained. 1. Normal groups not contaminated with artificial saliva showed greater shear bond strength than any other group contaminated with artificial saliva(P<0.01). 2. The shear bond strengths showed no significant difference between washed groups with distilled water and not washed groups after contamination with artificial saliva(P>0.05). 3. In normal groups, the shear bond strength of A group was significantly greater than in any other group(P<0.01). 4. In Sand G groups, fractures after shear bond strength tests occured adhesively on resintooth interface in all specimens. But in A groups, fracture of the normal group occured cohesively in dentin and fracture of the contaminated groups occured adhesively and cohesively. 5. On SEM examination, the number of resin strings penetrated into dentinal tubules were the greatest in normal groups, followed by, in descending order, washed groups and not washed groups after contamination with artificial saliva.

• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.1
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• pp.1-5
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• 1998

One cervical cancer cell line, C9, carrying human papillomavirus type 18 (HPV18) genes that is one of the major etiologic concoviruses for cervical cancer was characterized. This cell line was further characterized for its capacity related to the epithelial cell proliferation, stratification and differentiation in reconstituted artificial epithelial tissue. The in vitro construction of three dimensional artificial cervical opithelial tissue has been engineered using C9 epithelial cancer cells, human foreskin fibroblasts and a matrix made of type I collagen by organotypic culture of epithelial cells. The morphology of paraffin embedded artificial tissue was examined by histochemical staining. The artificial epithelial tissues were well developed having multilayer. However, the tissue morphology was similar to the cervical tissus having displasia induced by HPV infection. The characteristics of the artificial tissues were examined by determinining the expression of specific marker proteins. In the C9 derived artificial tissues, the expression of EGF receptor, as epithelial proliferation marker proteins for stratum basale was observed up to the stratum spinosum. Another epithelial proliferation marker for stratum spinosum, cytokerations 5/6/18, were observed well over the stratum spinosum. For the differentiation markers, the expression of involucrin and filaggrin were observed while the terminal differentiation marker, cytokeratins 10/13 was not detected at all. Therefore the reconstituted artificial epithelial tissues expressed the same types of differentiation marker proteins that are expressed in normal human cervical epithelial tissues but lacked the final differentiation capacity representing characteristics of C9 cell line as a cancer tissue devived cell line. Expression of HPV18 E6 oncoprotein was also observed in this artifical cervical opithelial tissue though the intensity of the staining was weak. Thus this artificial epithelial tissue could be used as a useful model system to examine the relationship between HPV-induced cervical oncogenesis and epithelial cell differentiation.

• Journal of Practical Engineering Education
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• v.13 no.2
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• pp.233-242
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• 2021

In this paper, as a liberal arts course for non-majors, we proposed a supervised learning artificial neural network parameter optimization method and a basic education method for activation function to design a basic artificial neural network subject curriculum. For this, a method of finding a parameter optimization solution in a spreadsheet without programming was applied. Through this training method, you can focus on the basic principles of artificial neural network operation and implementation. And, it is possible to increase the interest and educational effect of non-majors through the visualized data of the spreadsheet. The proposed contents consisted of artificial neurons with sigmoid and ReLU activation functions, supervised learning data generation, supervised learning artificial neural network configuration and parameter optimization, supervised learning artificial neural network implementation and performance analysis using spreadsheets, and education satisfaction analysis. In this paper, considering the optimization of negative parameters for the sigmoid neural network and the ReLU neuron artificial neural network, we propose a training method for the four performance analysis results on the parameter optimization of the artificial neural network, and conduct a training satisfaction analysis.

• Journal of The Korean Association of Information Education
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• v.24 no.5
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• pp.453-462
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• 2020

With the development of artificial intelligence, a lot of platforms have emerged that enable anyone to easily access and learn about artificial intelligence or create artificial intelligence models. Therefore, in this study, we analyzed various artificial intelligence education platforms and developed and proposed a SW education class plan using a framework-based artificial intelligence education platform for activating artificial intelligence based SW education. The artificial intelligence-based SW education framework aims to cultivate artificial intelligence literacy on the basis of computational thinking. In addition, a learner-centered project class was formed to include elements that could be fused with real life contexts or other subjects. Using this, with the theme of creating an artificial intelligence program to help separate garbage collection, a six-hour project-based class was developed and proposed using practical arts, social studies, and creative experiential activities. This project class was organized using a platform that is not difficult, such as AI Oceans and Entry.

• Journal of dental hygiene science
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• v.22 no.3
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• pp.156-163
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• 2022

Background: This study attempted to apply resin infiltrant (RI) as a method to maintain the effect of tooth bleaching treatment and compared it with fluoride varnish (FV) or artificial saliva to evaluate the effect. Methods: Sixty healthy lozenge specimens were classified into five groups. Group 1 was the negative control group, and discoloration was induced after artificial saliva treatment of the tooth specimen (G1_S+C). Group 2 was a positive control group, in which pigmentation was induced after bleaching treatment and artificial saliva treatment (G2 _B+S+C). Coloration was induced in group 3 (experimental group 1) after bleaching treatment and artificial saliva treatment, followed by application of fluorine varnish (G3_B+FV+S+C). Coloration was induced in Group 4 (experimental group 2) after applying RI after bleaching treatment and artificial saliva treatment (G4_B+RI+S+C). Pigmentation was induced in group 5 (experimental group 3) after bleaching treatment and artificial saliva treatment, followed by acid treatment (etching) and treatment with RI (G5_B+E+RI+S+C). Coffee and wine were used to induce discoloration. The lightness value (L^*) of the CIE L^*a^*b^* color system was obtained by image analysis. Kruskal-Wallis H analysis was performed for the mean difference in L^* values by group. Results: When coloration was induced with coffee, there was no significant difference in L^* value between artificial saliva (G2 _B+S+C), FV (G3_B+FV+S+C), and RI (G4_B+RI+S+C, G5_B+E+RI+S+C) groups. There was no significant difference in L^* values between the artificial saliva (G2 _B+S+C), FV (G3_B+FV+S+C), and RI (G4_B+RI+S+C, G5_B+E+RI+S+C) groups, even in the case of wine induced coloration. Conclusion: It was confirmed that artificial saliva or RI treatment had similar effects to the FV previously used to maintain the effect of tooth bleaching treatment.

• Journal of Biomedical Engineering Research
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• v.44 no.3
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• pp.167-175
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• 2023

Chest PA is the basic examination of radiographic imaging. Moreover, Chest PA's demands are constantly increasing because of the Increase in respiratory diseases. However, it is not meeting the demand due to problems such as a shortage of radiological technologist, sexual shame caused by patient contact, and the spread of infectious diseases. There have been many cases of using artificial intelligence to solve this problem. Therefore, the purpose of this research is to build an artificial intelligence dataset of Chest PA and to find a posture evaluation method. To construct the posture dataset, the posture image is acquired during actual and simulated examination and classified correct and incorrect posture of the patient. And to evaluate the artificial intelligence posture method, a posture estimation algorithm is used to preprocess the dataset and an artificial intelligence classification algorithm is applied. As a result, Chest PA posture dataset is validated with in over 95% accuracy in all artificial intelligence classification and the accuracy is improved through the Top-Down posture estimation algorithm AlphaPose and the classification InceptionV3 algorithm. Based on this, it will be possible to build a non-face-to-face automatic Chest PA examination system using artificial intelligence.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.177-179
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• 2022

In the Google Deepmind Challenge match, Alphago defeated Korea's Sedol Lee (human) with 4 wins and 1 loss in the Go match. Finally, artificial intelligence is going beyond the use of human intelligence. The Korean government's budget for the Digital New Deal is 9 trillion won in 2022, and an additional 301 types of data construction projects for artificial intelligence learning will be secured. From 2023, the industrial paradigm will change with the use and application of learning of artificial intelligence in all fields of industry. This paper conducts research to utilize artificial intelligence algorithms. Focusing on the analysis and judgment of data in artificial intelligence learning, research on the appropriate target and scope of application of algorithms in artificial intelligence machine learning and deep learning learning is conducted. This study will provide basic data for artificial intelligence in the 4th industrial revolution technology and artificial intelligence robot use in the 5th industrial revolution technology.

• Journal of Technologic Dentistry
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• v.46 no.1
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• pp.8-14
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• 2024

Purpose: This study compares the deformation of traditional resin dentures to resin dentures printed with digital light processing (DLP). Methods: Eleven edentulous research models were developed. Ten of them were made with traditional resin dentures. The remaining one was prepared for scanning and 3D (three-dimensional) printing. Ten traditional resin dentures were made, with the remaining artificial teeth created using 3D software and a DLP printer. Traditional resin dentures, 3D printed resin denture artificial teeth, and a denture base with artificial teeth were all cleaned simultaneously in an ultrasonic cleaner for 3 minutes. Three groups were assigned four artificial tooth measurement points, which were then measured with digital calipers. The measured data was analyzed using descriptive statistics. The significance test was conducted using a nonparametric test Kruskal-Wallis test due to the small number of specimens (α=0.05). Results: The traditional resin dentures had the lowest strain rate at -0.04%, while the group that manufactured only artificial teeth had the highest strain rate at -0.09%. However, no statistically significant difference was observed between the 3 groups (p>0.05). Conclusion: During ultraviolet-type ultrasonic cleaning, traditional resin dentures (TD group) and denture base with artificial teeth made of DLP (DD group) demonstrated stable durability, whereas the artificial teeth made of DLP (AD group) with only artificial teeth did not show a good deformation rate.