• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.4
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• pp.373-381
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• 2017

A Collaborative Optimization (CO) methodology for ring-stiffened composite material pressure hull of underwater vehicle is proposed. Structural stability and material strength are both examined. Lamination parameters of laminated plates are introduced to improve the optimization efficiency. Approximation models are established based on the Ellipsoidal Basis Function (EBF) neural network to replace the finite element analysis in layout optimizers. On the basis of a two-level optimization, the simultaneous structure material collaborative optimization for the pressure vessel is implemented. The optimal configuration of metal liner and frames and composite material is obtained with the comprehensive consideration of structure and material performances. The weight of the composite pressure hull decreases by 30.3% after optimization and the validation is carried out. Collaborative optimization based on the lamination parameters can optimize the composite pressure hull effectively, as well as provide a solution for low efficiency and non-convergence of direct optimization with design variables.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.40-45
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• 2008

This study describes tensile test results under room and elevated temperatures for AISI 304 stainless steel which is widely used for a airframe structural material. Tensile tests were conducted according to ASTM standards. Reliability analysis was conducted by using normal probability paper to evaluate A and B basis tensile strengths applicable to airframe structural design.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.577-580
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• 2003

Problem of repairing by boring is that it deteriorates stabelety and durability of structure by permeation of seawater from underneath after damage and repair of reinforcing rod regarding of spot. The purpose of this study is to improve the porblem by using the repair method of general boring to mend the of large mat basis. Direction of thes experiment is to apply the new repair material and the method to control the blazing fire factor caused by the crack from the foundation of large mat and also to estimate it's integrity. New method of construction is method of contruction that do speace scurity in vertical drilling and bottom useing water jet. New material used bantonite and rubberized asphalt. Test result existent repair method of construction large size mat basis perforation is difficult and reinforcing rod can be damaged coule there were a lot of problems with re-water leakage of crack repair region, but overcomes existent short coming by method that apply in this study.

• Korean Institute of Interior Design Journal
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• no.26
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• pp.121-128
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• 2001

This study deals with 'Sachlichkeit' , as essence of materiality that architectural building materials process, which forms the physical basis for actual building. There have beennu merous researches that deals with various elements that compose architecture, but the emphasis seemed to be concentrated on the meta-physical discussion concerning formal concept. An issue on sachlichkeit as materiality does not necessary mean to mention production process of architecture, rather it is aim of this study to seek possibility to find elements that generate architectural form, through interpreting meaning of materials as substructure generator to make architectural possible. Architectural act can be defined as a process where physical material in life is composed into architecture by the hands of architect. Material used in life is composed into architecture by the hands of architect. Material used in this process basically has neutral characteristic, so 'Sachlichkeit'solely depends on the intentions of architects. This study interprets the intention of architects through the frame of modern-basis proposed by Hilberseimer, and a result architecture is defined as an object projected by architect's subjectivity.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.301-304
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• 2001

Hot-compression tests were carried out to investigate the hot workability of Ti64 and Ti6246 alloys at different temperatures and strain rates. Processing maps were developed on the basis of the dynamic material model unifying the relationship among constitutive behavior, hot workability and microstructure development. Stable regions, defined on the basis of four stability criteria 0${\delta}log(m)/\frac{\bot}{\varepsilon})<0$, s<1 and ${\delta}log(s)/\frac{\bot}{\varepsilon})<0$, were found to be associated with dynamic recovery and recrystallization.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.1
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• pp.1-5
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• 2005

A new model of plasma etch process was constructed by using a radial basis function network (RBFN). This technique was applied to an etching of silicon carbide films in a NF$_3$ inductively coupled plasma. Experimental data to train RBFN were systematically collected by means of a 2$^4$ full factorial experiment. Appropriateness of prediction models was tested with test data consisted of 16 experiments not pertaining to the training data. Prediction performance was optimized with variations in three training factors, the number of pattern units, width of radial basis function, and initial weight distribution between the pattern and output layers. The etch responses to model were an etch rate and a surface roughness measured by atomic force microscopy. Optimized models had the root mean-squared errors of 26.1 nm/min and 0.103 nm for the etch rate and surface roughness, respectively. Compared to statistical regression models, RBFN models demonstrated an improvement of more than 20 % and 50 % for the etch rate and surface roughness, respectively. It is therefore expected that RBFN can be effectively used to construct prediction models of plasma processes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.255-258
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• 2000

The new approach for synthesis of novel condensation monomers and polyimides on the basis of them was developed. The correlation between synthesis regularities, structure and properties of monomers and polyimides was studied. The areas of industrial application of synthesized polymer were determined.

• Archives of design research
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• v.15 no.2
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• pp.5-18
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• 2002

Recently, the West's interest on Buddhism has been uprising. If the interest on Buddhism is especially from Western intellectuals, it will surely be the motive to change, the future of Western society. Actually, while the West has been interested in the material civilization on the basis of Christianity, the East has been pursuing after the spiritual culture on the basis of Buddhism. However, what does it mean that many of civilized westerners have come to dislike the manner of scientific pursuit and strict rationality which made them wealthy materially\ulcorner It means that they have felt their ideologies which is based on the Christian culture, has met an end or at least they have started to get interested in the Eastern ideology, 'Buddhism'. Particularly, if we agree that industrial design is a field of basis on the stringent rationality, and is a field of applied science on the basis of technology and production, it surely must have rather been influenced by Christian culture than Buddhism. But regardless of material richness by Christian culture, some Western intellectuals'secession from christianity means that their pursuit of material civilization doesn't help much in chasing after human original happiness. Instead, they are charmed by the fact that their mental illness problem, which is the result of the incessant pursuit of materialism, can be salved more 'scientifically'rather by Buddhism than Christianity. Compared with the westerners'spiritual unhappiness by the strong pursuit of material, Buddhism lowers their passion for material and help to lead their lives happily with least'pursuit of materialism. In this sense, I insist that we need to study'Design'from a viewpoint of Buddhist idea.

• Journal of the Korean Society for Heat Treatment
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• v.21 no.4
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• pp.213-218
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• 2008

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.664-667
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• 2004

It may have to establish the definite standard for performance evaluation basis about cementitious waterproofing material in job site that applied the method of construction formed cement waterproof course on concrete surface In present paper shows the effective selection method of waterproof layer of optimum thickness for economic performance as evaluating of the need thickness on waterproof property of penetrating waterproofing material.