• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.1117-1120
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• 2008

In order to develop an Ultra High Performance Concrete (UHPC) suited to the Korean conditions, KICT has carried out several parts of research in the field of UHPC from 2003. KICT developed UHPC which was a structural material exhibiting very remarkable mechanical performances with compressive strength, tensile strength and flexural strength rising up to 200MPa, 15MPa and 35MPa, respectively. In addition, this material presents exceptional durability regard to the very low diffusion and penetration speeds of noxious substances like chloride ions. This 200MPa strength concrete has been effectively adopted for the construction of bridges like Sherbrooke Bridge in Canada in 1997, Sunyu Bridge in Korea in 2002, Meata Bridge in Japan in 2003, Sheperds Guelly Creek Bridge, the first ultra-high strength concrete highway bridge in Australia in 2004 and, more recently in 2005, Mars Hill highway bridge in USA in 2005. The construction of structures using ultra high performance concrete is a worldwide development trend of concrete technology for the construction of advanced facilities in the 21st century.

• Journal of Digital Convergence
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• v.11 no.7
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• pp.185-192
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• 2013

The purpose of this study is to set the relationship between each parts that forms the engine of an automobile based on the 3D visualization technology which is able to be learned according to the skill of the operator in the industry field and to recommend the auto parts using a task ontology. A visualization method was proposed by structuring the complex knowledge by signifying the link and the node in forms of a network and using SOM which can be shown in the form of 3 dimension. In addition, by using is-a Relationship-based hierarchical Taxonomy setting the relationship between each of the parts that forms the engine of an automobile, to allow a recommendation using a weighted value possible. By providing and placing the complex knowledge in the 3D space to the user for an opportunity of more realistic and intuitive navigation, when randomly selecting the automobile parts, it allows the recommendation of the parts having a close relationship with the corresponding parts for easy assembly and to know the importance of usage for the automobile parts without any special expertise.

• Journal of Science and Technology Studies
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• v.12 no.1
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• pp.79-106
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• 2012

The paper discusses the issue of reality related to interaction between users and electronic figures that mediate by online game system. MMORPG(Massively Multiple Online Role Playing Game) has been known as virtual world that physically and electronically interconnect users and mechanical elements over huge area. Already game items have became a kind of reality for some users long time ago. How these figures could have been regarded as realities? It suggests to take place the temporality of practice around game world. Tremendous practices of human and machines produce their relations and these relations are reinforced self-referentialy. They could constitute their time-space frame that be situated a figure as the something in it.

• Journal of the Korea Concrete Institute
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• v.13 no.2
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• pp.146-152
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• 2001

The fractal geometry is a non-Euclidean geometry which discribes the naturally irregular or fragmented shaps, so that it can be applied to fracture behavior of materials to investigate the fracture process. Fractal curves have a characteristic that represents a self-similarity as an invariant based on the fractal dimension. This fractal geometry was applied to the crack growth of cementitious composites in order to correlate the fracture behavior to microstructures of cemposite composites. The purpose of this study was to find relationships between fractal dimensions and fracture energy. Fracture test was carried out in order to investigate the fracture behavior of plain and fiber reinforced cement composites. The load-CMOD curve and fracture energy of the beams were observed under the three point loading system. The crack profiles were obtained by the image processing system. Box counting method was used to determine the fractal dimension, D$_{f}$. It was known that the linear correlation exists between fractal dimension and fracture energy of the cement composites. The implications of the fractal nature for the crack growth behavior on the fracture energy, G$_{f}$ is appearent.ent.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.1
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• pp.89-98
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• 2002

Optical current sensor and optical voltage sensor modules were designed and fabricated to improve measurement error and insulation in automatic power distributor By using Faraday effect, optical current sensor with an $\alpha$-iron core was designed and fabricated to minimize current induction of the other phase and was optimized to maintain linearity. Optical voltage sensor was fabricated owing to the pockets effect and adopted spatial electric field type because of small room in an automatic power distributor. To connect a distributor with an external terminal for signal processing, optical multi connector was designed, fabricated and tested for coupling loss and gas leakage. The linearity of optical current sensor for applied current maintains variation of smaller than 2.5% for applied current range from 20A to 700A. The linearity of optical voltage sensor was smaller than 1% for appling voltage from 6.6kV to 19.8kV. Since the measured characteristics are good, these devices can be considered as being applicable in practice.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.251-254
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• 2007

A 10-year-old intact female Yorkshire terrier dog was referred for evaluation of marked abdominal distension and hemorrhagic effusion. Abdominal radiography and ultrasonography demonstrated abdominal effusion and intraabdominal mass with anechoic cystic components. On ascites cytology, neoplastic epithelial cells with vacuolated cytoplasm and prominent nucleoli were identified. Magnetic resonance imaging (MRI) showed the well-defined, heterogeneous, and large mass filled the intraabdominal cavity. At necropsy, a large mass arising from the right ovary was observed. Histopathologically, the mass was composed of papillary structures lined by neoplastic epithelial cells. The dog was definitively diagnosed as malignant ovarian adenocarcinoma with papillary pattern based on clinical and histopathological findings.

• 한국노년학
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• v.32 no.3
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• pp.801-817
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• 2012

This study focused on the relationship between elderly's participation in lifelong education(participation availability, participating fields) and ego integrity. To verify the correlation of two variables, mediating model structured by life satisfaction was used. The data was Seoul Welfare Panel Data made by Seoul Welfare Foundation in 2010 and the total subject was 1,862 elderly aged over 60. When it comes to research methods, structured equation analysis for verifying the mediating effect was practiced. The findings are as follows: First, life satisfaction did function as partial mediator on relationship between elderly's participation in lifelong education and ego integrity. Second, elderly's life satisfaction increased as participating in field of language, not in field of culture and art. Ego integrity of elderly was increased as participating in field of culture and art, not in field of self-improvement and hobby. This study indicates theoretical and practical interventions to promote elderly's lifelong education based on the conclusion elderly's lifelong education participation in the aging society has positive effects on life satisfaction and ego integrity are meaningful for successful aging.

• Journal of Digital Convergence
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• v.17 no.10
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• pp.439-446
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• 2019

Feminism on the theme of gender equality is emerging as an important issue in the overall Korean culture. Feminism is not only a level of claiming or advocating women's rights, but an essential subject of gaze and thought, not a distorted, artificially portrayed image of women distorted or typified in a story created by men in the past It is a film that explores the problem of the individual's life in society fundamentally. Jun Koeun's movie' 'micro-habitat'(2018) 'expresses a feminist theme that shows a strong self - selection and transcendental thinking in male - oriented stereotypes and inequal social structure. The film, which focuses on the public insight into society and the enhancement of the ideal human being from the viewpoint that the public film should lead the educated enlightenment character that raises the broad insight into the world and lead the mature social culture, I think it will play a big role.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.4
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• pp.209-220
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• 2019

Even though the scale of hard structures for beach stabilization should carefully be determined such that these structures do not interrupt the great yearly circulation process of beach sediment in which the self-healing ability of natural beach takes places, massive hard structures such as the submerged breakwater of wide-width are frequently deployed as the beach stabilization measures. On this rationale, asymmetric ripple mat by Irie et al. (1994) can be the alternatives for beach stabilization due to its small scale to replace the preferred submerged breaker of wide-width. The effectiveness of asymmetric ripple mat is determined by how effectively the vortices enforced at the contraction part of flow area over the mat traps the sediment moving toward the offshore by the run-down. In order to verify this hypothesis, we carry out the numerical simulations based on the Navier-Stokes equation and the physically-based morphology model. Numerical results show that the asymmetric ripple mat effectively capture the sediment by forced vortex enforced at the apex of asymmetric ripple mat, and bring these trapped sediments back to the beach, which has been regarded to be the driving mechanism of beach stabilization effect of asymmetric ripple mat.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.9
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• pp.729-738
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• 2021

Feedback flow control using an artificial neural network was numerically investigated for NACA0015 Airfoil to suppress flow separation on an airfoil. In order to achieve goal of flow control which is aimed to reduce the size of separation on the airfoil, Blowing&Suction actuator was implemented near the separation point. In the system modeling step, the proper orthogonal decomposition was applied to the pressure field. Then, some POD modes that are necessary for flow control are extracted to analyze the unsteady characteristics. NARX neural network based on decomposed modes are trained to represent the flow dynamics and finally operated in the feedback control loop. Predicted control signal was numerically applied on CFD simulation so that control effect was analyzed through comparing the characteristic of aerodynamic force and spatial modes depending on the presence of the control. The feedback control showed effectiveness in pressure drag reduction up to 29%. Numerical results confirm that the effect is due to dramatic pressure recovery around the trailing edge of the airfoil.