• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.245-248
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• 1996

In this study, piezoelectric transducers were designed and manufactured using PZT-5A which had relatively high electromechanical coefficient, NDT system was developed with was able to inspect automatically using stepping motors, PC-Lab, and PC-Scope The optimum design conditions for NDT were presented and verified comparing PZT-5A probes with comercial probes. It was proved with comercial probes. It was proved by simulation and experiments that Epoxy is good as material of matching and backing layers. The envelope was reduced 60% with matching layer and 76% with matching and backing layer. NDT was successfully carried out for aluminum test pieces. Distance error of PZT-5A probe was 2.8%.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.5
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• pp.833-847
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• 2015

Although the transverse butt weld method with ceramic backing strip has been widely used in various industrial fields for its fabricational convenience, it is rarely used in offshore industries since the fatigue strength of the weld joint has not been proved sufficiently. This study conducted fatigue tests for series of butt weld specimens with horizontal (2G) and vertical (3G) welding positions in order to verify the fatigue strength compared to S-N curve by DNV (Det Norske Veritas), IIW (International Institute of Welding) and Eurocode 3. The difference of the 2G specimens and the 3G specimens are investigated in terms of angular distortion and the effect on the fatigue strength are analyzed.

• 한국디지털정책학회:학술대회논문집
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• 2003.12a
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• pp.101-114
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• 2003

In industrialised countries, innovation is a key source of economic growth. Research is a key driver of technological innovation and involves the process of systematic investigation and/or experimentation to discover new knowledge. The Governments' industry innovation policy supports a business focus on Research and Development (R&D) through a range of programs in order to achieve these aims. The Innovation Statement, launched by the Australian Prime Minister in January 2001, commits an additional $3 billion over five years to encourage and support innovation. The Australian Government aims to build world competitive firms and strong research capability in industry to strengthen Australia's international competitiveness and increase national prosperity. It develops policies and programs to enhance investment in innovation. The Australian Government also undertakes analysis and comparisons of innovation policies, instruments and approaches to maintain a leading-edge National Innovation System. This includes analysis of the innovation activities of other nations, and evaluation of the impacts of innovation policies and programs on Australia's institutions and enterprises. This paper examines Australia's Innovation policies, Backing Australian Ability.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2314-2316
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• 2000

In the construction of successful fuzzy models and/or controllers for nonlinear systems, identification of a good fuzzy Neural inference system is an important yet difficult problem, which is traditionally accomplished by trial and error process. In this paper, we propose a systematic identification procedure for complex multi-input single- output nonlinear systems with DNA coding method.DNA coding method is optimization algorithm based on biological DNA as are conventional genetic algothms (GAs). We also propose a new coding method for applying the DNA coding method to the identification of fuzzy Neural models. To acquire optimal TS fuzzy model with higher accuracy and economical size, we use the DNA coding method to optimize the parameters and the number of fuzzy inference system.

• Journal of Digital Convergence
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• v.1 no.1
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• pp.31-44
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• 2003

In industrialised countries, innovation is a key source of economic growth. Research is a key driver of technological innovation and involves the process of systematic investigation and/or experimentation to discover new knowledge. The Governments' industry innovation policy supports a business focus on Research and Development (R&D) through a range of programs in order to achieve these aims. The Innovation Statement, launched by the Australian Prime Minister in January 2001, commits an additional 53 billion over five years to encourage and support innovation. The Australian Government aims to build world competitive firms and strong research capability in industry to strengthen Australia's international competitiveness and increase national prosperity. It develops policies and programs to enhance investment in innovation. The Australian Government also undertakes analysis and comparisons of innovation policies, instruments and approaches to maintain a leading-edge National Innovation System. This includes analysis of the innovation activities of other nations, and evaluation of the impacts of innovation policies and programs on Australia's institutions and enterprises. This paper examines Australia's Innovation policies, Backing Australian Ability.

• Journal of Biosystems Engineering
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• v.20 no.1
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• pp.87-94
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• 1995

When farmer loads and unloads farm products with a trailer, linked to a tractor, the tractor-trailer is backed up to the loading duck. However, travelling backward is not easy and takes a time for even skilled operators. Therefore, unmanned backing up is necessary to save the effort. A backward controller of tractor-trailer was simulated using fuzzy logic and genetic algorithms. Operators drive the tractor-trailer back and forth several times for backing up to the loading duck. As the operators did it, a backward controller was designed using fuzzy logic. And genetic algorithms was applied to improve the performance of the backward controller. With the strings coded with the fuzzy membership functions, genetic operations were carried out. After 30 generations, the best fitted fuzzy membership functions were found. Those membership functions were used in the fuzzy backward controller. The fuzzy controller combined with genetic algorithms showed the better results than the fuzzy controller did alone.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.9
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• pp.111-116
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• 1998

The squeal of drum brakes was investigated numerically and experimentally. Modal testings were performed for shoes, drums, backing plates and their assemblies. In order to predict the squeal phenomena, stability analysis was performed based on a simplified self-excited vibration model. Based on modal testings, the dynamic properties of the brake elements and the parameters used in this analysis were determined. The geometries of shoes and drums were also considered. The result shows that the modification methods of the shoe and the drum design are feasible for noise reduction.

• Proceedings of the Korean Vacuum Society Conference
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• 2007.08a
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• pp.119-119
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• 2007

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5419-5424
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• 2014

A weld scallop is a small quadrant or half circle type hole installed in the weld line cross area for easy welding operation. Many types of T-bars with a scallop can be welded in a block assembly stage in shipbuilding. The difficulties arise from the fact that scallops are to be filled by build-up welding after welding of the cross line is complete. In this study, a non-scallop block joint welding method was developed using special type CBM (ceramic backing material). The wedge shaped CBM was devised to insert a CBM into just the V groove of weld line cross area without weld scallop. A saw-toothed shape was adopted for easy cutting of the unnecessary part in the CBM fitting process. The applicability of the developed method was verified through welding experiments based on the yard welding conditions.

• Proceedings of the KWS Conference
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• 2009.11a
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• pp.55-55
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• 2009

FGB(Flexible Glasswool Backing) Submerged Arc Welding has been one of the main welding processes for one side butt welding in shipbuilding industries, which can efficiently improve the welding productivity by the addition of a supplementary filler metal into the molten weld pool. As recent ships have become larger in size, the application of high tensile and higher grade of steels has been continuously increased. Single pass FGB SA welding process accompanies such a high heat input when welding thick plates that the mechanical properties of weld metal can be dramatically degraded. This study has been performed in order to obtain high toughness and tensile properties of high heat input FGB SA welds, and to evaluate the effect of alloy elements on their mechanical properties. To complete welding 25mm-thick EH36 grade steel plate by single pass, 1.2mm diameter and 1.0mm long cut wires has been distributed in the groove before welding, and three different test coupons have been made using C-1.5%Mn, C-1.8%Mn-0.5%Mo, and C-1.4%Mn-1.7%Ni cut wires to investigate the influence of nickel(Ni) and molybdenum(Mo) on the mechanical properties of welds. Test results showed that the addition of Ni and Mo effectively promotes the formation of Acicular Ferrite(AF), while significantly reducing the amount of Grain Boundary Ferrite(GBF) in weld metal microstructures, which resulted in a beneficial effect on low temperature impact toughness and strength.