• Journal of Powder Materials
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• v.22 no.5
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• pp.337-343
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• 2015

Powder compaction is a continually and rapidly evolving technology where it is a highly developed method of manufacturing reliable components. To understand existing mechanisms for compaction, parameter investigation is required. Experimental investigations on powder compaction process, followed by numerical modeling of compaction are presented in this paper. The experimental work explores compression characteristics of soft and hard ductile powder materials. In order to account for deformation, fracture and movement of the particles, a discrete-finite element analysis model is defined to reflect the experimental data and to enable investigations on mechanisms present at the particle level. Effects of important simulation factors and process parameters, such as particle count, time step, particle discretization, and particle size on the powder compaction procedure have been explored.

• 한국연소학회:학술대회논문집
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• 2002.11a
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• pp.89-95
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• 2002

A hybrid De- NOx technique of non-thermal plasma and $NH_3$ SCR process has been investigated to remove NOx from 300 hp marine engine exhaust under the low temperature conditions, i.e. $100-200^{\circ}C$. Fundamental investigation with Diesel-like simulant gas was also conducted. The performance of the present technique has been demonstrated by treating real diesel exhaust gases, in which high contents of soot, water vapor, $SO_2$, NOx, and unburned HC are included. Detailed engineering data for evaluating the feasibility of the technique are provided in the present investigation.

• Transactions of Materials Processing
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• v.11 no.7
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• pp.596-600
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• 2002

The ultrasonic bonding method and its feasibility are investigated in this work for joining the micro components and MEMS packaging. The ultrasonic bonding process is analyzed using a lumped mode, and preliminary experiments using the eutectic solder and copper pin were carried out to verify possibility to MEMS packaging. The ultrasonic bonding process appears to be adequate for MEMS packaging by providing localized heating at the selected area. Microscopic behavior of the bond joint through ultrasonic vibration needs further investigation.

• Transactions of Materials Processing
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• v.14 no.1 s.73
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• pp.57-64
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• 2005

This study deals with the cold forging process design for shaft in the main part of automobile motors with rectangular deep groove. In forging process, the accuracy and die lift is very important because it have influence on reduction of the production cost and the increase of the production rate. Therefore, it is necessary to develop the manufacturing process of shaft by cold forging., process variables are the cropped face angle of billet and the eccentric load of punch. The former is derived from cropping test, the latter is occurred by clearance between container and preform. Also, grooved preform select the process variable for decrease in punch deflection. We investigate that a deflection of punch and a deformation of preform to every process variables. Through this investigation, we suggest the optimal preform and process design, expect to be improved the tool life in forging process.

• Proceedings of the Materials Research Society of Korea Conference
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• 1996.05a
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• pp.64-64
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• 1996

• Journal of The Korean Association For Science Education
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• v.27 no.8
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• pp.724-742
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• 2007

The purpose of this study was to develop a scientific inquiry model that makes scientific inquiry accessible to science teachers as well as students. To develop a scientific inquiry model, we investigated the research process demonstrated by ten scientists who were working at academic research institutions or industrial research institutions. We collected data through scientists' journal articles, lab meetings and seminars, and observation of their inquiry process. After we analyzed the scientists' inquiry strategies and processes of inquiry, we finally developed the Scientist's Methodology of Investigation Process model named SMIP. The SMIP model consists of four domains, 15 stages, and link questions, such as "if, why", and "how". The SMIP model stressed that inquiry process is a selective process rather than a linear or a circular process. Overall, these findings can have implication science educators in their attempt to design instruction to improve the scientific inquiry process.

• Proceedings of the Microbiological Society of Korea Conference
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• 2002.10a
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• pp.73-75
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• 2002

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.157-164
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• 2019

This paper investigates applicable methods of using machine learning(ML) in design process that is currently at infant stage and discuss how designers can use machine learning in UX design process. This research is differentiated from design method for machine learning-based products or services. For this purpose, this paper conducted literature reviews and case investigation and discussed three categories of design method of combination with such as 1) UX design centered ML, 2) ML system centered UX, and 3) UX-ML matchmaking. With this investigation, the workshop was conducted with specifically applicable methods of 2) and 3) for designers. Throughout the workshop, this paper analyzed each method' process with pros and cons in details. Throughout the process, this paper suggests precise methods of applying ML into UX design process.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.111.1-111
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• 2003

• Journal of Conservation Science
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• v.35 no.1
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• pp.33-40
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• 2019

During the conservation and maintenance of the birthplace center yard of President Asan Yoon Bosun, four porcelain enamel dishware were excavated from the central yard well. The glaze layer of excavated enamel was severely damaged; hence, the conservation process was done rapidly. In addition, scientific investigation and analysis were conducted to confirm the material properties of the glaze layer. It was confirmed that the outer surface was inverted and dried, while the inner surface was upright and fired during the glazing and drying process by measuring the film thickness. By examining the breakup phenomenon, the breaking up of the white enamel on the colored enamel was confirmed. This indicates that the colored glaze rose to the surface depending on the density of the colored glaze and white glaze. The investigation of the cross-section of the film confirmed that the lower layer formed according to the bonding properties with metal during the glazing process. Analysis of the constituents of the identified lower layer confirmed that there are differences between the specific components of the metal oxide of the lower layer and the surface color development of the upper layer.