• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.381-386
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• 2001

This paper reports on the development of micro power system under way at Seoul National University. The interdisciplinary tin consists of members with various backgrounds of mechanics and materials. The need for micro power systems is explained, and a turbine under development is described. Design, and fabrication are introduced, and technical challenges in each phase are described. Furthermore, the interaction between the available fabrication methods and design is explained. Design involves use of commercially available codes to analyze flow fields, and fabrication takes advantage of the silicon wafer etching processes used to manufacture semiconductor devices.

• Molecular & Cellular Toxicology
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• v.2 no.4
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• pp.279-284
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• 2006

This paper describes the fabrication methods of a carbon nanotube (CNT) filter and a microdialysis chip. A CNT filter can help perform dialysis on a microfluidic chip. In this study, a membrane type of a CNT filter is fabricated and located in a microfluidic chip. The filter plays a role of a dialysis membrane in a microfluidic chip. In the fabrication process of a CNT filter, individual CNTs are entangled each other by amide bonding that is catalyzed by 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The chemically treated CNTs are shaped to form a CNT filter using a PDMS film-mold and vacuum filtering. Then, the CNT filter is sandwiched between PDMS substrates, and they are bonded together using a thin layer of PDMS prepolymer as adhesive. The PDMS substrates are fabricated to have a microchannel by standard photo-lithography technique.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.12-13
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• 2018

Reinforced concrete works account for 40 to 50 percent of the total construction work. However, the shortage of construction workers is a problem in the delay of the construction period of reinforced concrete. The partial rebar prefabrication is one of the ways to shorten construction period. Thus, this study compared the partial rebar prefabrication and field fabrication method through work sampling. As a result, the partial rebar prefabrication showed a significant decrease in time compared to field fabrication method. As a result of this study, it is expected to be used as a reference for the efficient selection of reinforced concrete methods.

• Journal of the Korean Ceramic Society
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• v.53 no.5
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• pp.478-482
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• 2016

Metal-supported SOFCs have been investigated to overcome the disadvantages of ceramic-supported SOFCs, including issues related to mechanical strength and sealing. In the case of ceramic-supported cells, the mechanical support is a brittle ceramic or cermet, and it contains expensive materials. However, metal-supported cells utilize ceramic layers that are only as thick as necessary for electrochemical functioning, thereby compensating for the disadvantages of ceramic-supported cells. The mechanical support is fabricated from inexpensive and robust metals, and the electrochemically active layers are applied directly to the metal support. The metal-supported SOFCs thus can provide a reduced system cost, ease of manufacturing, and operational advantages. Owing to these features, metal-supported SOFCs are a very promising candidate for commercialization. Given the importance of studying worldwide trends in metal-supported SOFC research for performance evaluation, this paper reviews development trends with a focus on fabrication methods. Furthermore, a novel fabrication method developed in KAIST is discussed.

• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.964-969
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• 2014

In Super Junction MOSFET, Charge Balance is the most important issue of the trench filling Super Junction fabrication process. In order to achieve the best electrical characteristics, the N type and P type drift regions must be fully depleted when the drain bias approaches the breakdown voltage, called Charge Balance Condition. In this paper, two methods from the fabrication process were used at the Charge Balance condition: Trench angle decreasing process and Bottom implantation process. A lower on-resistance could be achieved using a lower trench angle. And a higher breakdown voltage could be achieved using the bottom implantation process. The electrical characteristics of manufactured discrete device chips are compared with those of the devices which are designed of TCAD simulation.

• Journal of Power System Engineering
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• v.18 no.6
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• pp.7-12
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• 2014

The effect of various synthesis conditions in the fabrication of graphene using the exfoliation methods has been investigated. Graphite oxide and graphene fabricated by various synthesis conditions were identified by SEM and XRD. Graphite oxide was made from graphite by the chemical oxidation, and graphene was manufactured from graphite oxide by thermal exfoliation method. As a result, it is confirmed that graphite oxide was well formed from graphite, and the graphene could be obtained from graphite oxide. And it was found that the interlayer spacing between the graphene layers depended on the reaction time and particle size, regardless of the reaction temperature from $5^{\circ}C$ to $25^{\circ}C$.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1053-1059
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• 2009

Construction system modeling can enhance work performance by following the behaviors of a system. System behaviors may originate from physical aspects of a system, namely operation level variables, or from non-physical aspects of a system known as context level variables. However, construction system modelers usually focus on only one type of system variable (i.e., operation level or context level) which can lead to less accurate results. Hybrid modeling with System Dynamics (SD) and Discrete Event Simulation (DES) is one of the approaches that has been utilized to address this issue. In this research, an SD-DES hybrid model of a steel fabrication shop is developed, and the benefits of capturing context level variables together with operation level variables in the model are discussed.

• Journal of Industrial Technology
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• v.43 no.1
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• pp.49-55
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• 2023

Cluster tools are extensively employed in various wafer fabrication processes within the semiconductor manufacturing industry, including photo lithography, etching, and chemical vapor deposition. Contemporary fabrication facilities encounter customer orders with technical specifications that are similar yet slightly varied. Consequently, modern fabrications concurrently manufacture two or three different wafer types using a cluster tool to maximize chamber utilization and streamline the flow of wafer lots between different process stages. In this review, we introduce two methods of concurrent processing of multiple wafer types: 1) concurrent processing of multiple wafer types with different job flows, 2) concurrent processing of multiple wafer types with identical job flows. We describe relevant research trends and achievements and discuss future research directions.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.5
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• pp.695-703
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• 2000

The purpose of this study was to evaluate the effects of fabrication and tightening methods of gold cyliner on the preload of the standard abutment. Three linear strain gauges (KFR-02N-120-C1-23, Kyowa, Japan) were mounted longitudinally on the 5.5mm Standard abutment (Nobel Biocare, Sweden) and three kinds of gold cylinders such as, as-received gold cylinder, gold cylinder after casting, and plastic cylinder after casting with type IV gold alloy were connected over the top of the standard abutment. Two kinds of tightening methods, such as manual torque with handhold screwdriver and electronic torque using Electronic torque controller were used to generate preload on the abutment. The result were as follows; 1. The preload generated by tightening cast plastic cylinder with handhold screw driver, was the lowest among the six groups. 2. The preload generated by cast plastic cylinder was lower than those by gold cylinders regardless of the tightening methods. 3. The electronic torque controller produced higher torque values than the handheld screwdriver.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.2
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• pp.213-223
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• 2013

This study presents the process of fashion item development with velvet through creative thinking methods. Creativity is one of the most important requirements for a successful job career and education enhancing creative thinking is needed in the area of fabrication, product design, and marketing strategy development. Velvet was selected as a research stimulus because it is a luxurious fabric with various differential properties such as a soft touch, unique luster, excellent drapability, and fine physical properties. The research methodology included creative thinking methods review, the selection of the tools, idea sourcing and listing, sequential idea evaluation and sample product making. After review of the various creative thinking methods, a combination method and forced connection method were employed as research tools to confirm the usefulness of creative thinking training because of their independence of use and application simplicity. A total of 12 university students participated as subjects in this research. After some training, each student derived ten ideas for velvet products that utilized a combination method and forced connection method. A total of 120 ideas were evaluated for novelty, technical possibility, practicality, and marketability; subsequently, 24 ideas were adopted and developed as sample products. The effectiveness of creativity education in fabrication and product design classes was verified through the whole process of product planning.