• Title/Summary/Keyword: Research Process

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Feasibility study on developing productivity and quality improved three dimensional printing process

  • Lee, Won-Hee;Kim, Dong-Soo;Lee, Taik-Min;Lee, Min-Cheol
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.2160-2163
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    • 2005
  • Solid freeform fabrication (SFF) technology plays a major role in industry and represents a reasonable percentage of industrial rapid prototyping/tooling/manufacturing (RP/RT/RM) development applications. However, SFF technology still has long way to progress to achieve satisfactory process speed, surface finish and overall quality improvement of its application. Today, three dimensional printing (3DP) technique that is one of SFF technology is receiving many interests, and is applied by various fields. It can fabricate three dimensional objects of solid freeform with high speed and low cost using ink jet printing technology. However, need long curing time after manufacture completion. And it must do post-processing process necessarily to heighten strength of objects because strength of fabricated objects is very weak. Therefore, in this study, we proposed an improved 3DP process that can solve problems of conventional 3DP process. The general 3DP process is method to spout binder simply through printer head on powder, but proposed process is method to cure jetted UV resin by UV lamp after jet UV resin using printhead on powder. The hardening of resin is achieved strongly at early time by UV lamp in proposed method. So, the proposed process can fabricate three dimensional objects with high speed without any post-processing.

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A Process Management Framework for Design and Manufacturing Activities in a Distributed Environment (분산 환경하의 설계 및 제조활동을 위한 프로세스관리기법 연구)

  • Park, Hwa-Kyu;Kim, Hyun;Oh, Chi-Jae;Jung, Moon-Jung
    • The Journal of Society for e-Business Studies
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    • v.2 no.1
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    • pp.21-37
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    • 1997
  • As the complexity in design and manufacturing activities of distributed virtual enterprises rapidly increases, the issue of process management becomes more critical to shorten the time-to-market, reduce the manufacturing cost and improve the product quality. This paper proposes a unified framework to manage design and manufacturing processes in a distributed environment. We present a methodology which utilizes process flow graphs to depict the hierarchical structure of workflows and process grammars to represent various design processes and design tools. To implement the proposed concept, we develop a process management system which mainly consists of a cockpit and manager programs, and we finally address a preliminary implementation procedure based on the Object Modeling Technique. Since the proposed framework can be a formal approach to the process management by providing formalism, parallelism, reusability, and flexibility, it can be effectively applied to further application domains of distributed virtual enterprises.

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Sensitivity Analysis of Fabrication Parameters for Dry Process Fuel Performance Using Monte Carlo Simulations

  • Park Chang Je;Song Kee Chan;Yang Myung Seung
    • Nuclear Engineering and Technology
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    • v.36 no.4
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    • pp.338-345
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    • 2004
  • This study examines the sensitivity of several fabrication parameters for dry process fuel, using a random sampling technique. The in-pile performance of dry process fuel with irradiation was calculated by a modified ELESTRES code, which is the CANDU fuel performance code system. The performance of the fuel rod was then analyzed using a Monte Carlo simulation to obtain the uncertainty of the major outputs, such as the fuel centerline temperature, the fission gas pressure, and the plastic strain. It was proved by statistical analysis that for both the dry process fuel and the $UO_2$ fuel, pellet density is one of the most sensitive parameters, but as for the fission gas pressure, the density of the $UO_2$ fuel exhibits insensitive behavior compared to that of the dry process fuel. The grain size of the dry process fuel is insensitive to the fission gas pressure, while the grain size of the $UO_2$ fuel is correlative to the fission gas pressure. From the calculation with a typical CANDU reactor power envelop, the centerline temperature, fission gas pressure, and plastic strain of the dry process fuel are higher than those of the $UO_2$ fuel.

Differences in Characteristics of Recycled ONP for CaCO3 Adding Techniques (CaCO3 첨가법에 따른 재생 ONP의 특성변화)

  • Ahn, Young-Jun;Nam, Seong-Young;Um, Nam-Il;Ahn, Ji-Whan;Han, Choon
    • Journal of the Korean Ceramic Society
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    • v.51 no.2
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    • pp.97-102
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    • 2014
  • In order to improve the refresh rate of old newspaper(ONP), PCC shape-controlling experiments were carried out. The effect of a PCC polymorph on improving the quality of old newspaper was studied for a transformation from waste paper to eco-friendly paper. The synthesis of PCC consists of an in-situ process and a loading process to enhance the refresh rate of old newspaper. The characteristics between the in-situ process and the loading process could be analysed by SEM analyses of coated fiber surfaces. The retention rate ranges from 65 to 67% after the application of the in-situ process, and that after the loading process ranges from 55 to 58%. The retention rates thus show a difference of about 7-10%. In addition, the whiteness and ERIC characteristics of the in-situ process gave more efficient results than those of the loading process.

A Study on Mariners' Standard Behavior for Collision Avoidance (3) - Modeling of the execution process of an avoiding action based on human factors -

  • Park, Jung-Sun;Kobayashi, Hiroaki;Yea, Byeong-Deok
    • Journal of Navigation and Port Research
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    • v.32 no.4
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    • pp.279-285
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    • 2008
  • We have proposed modeling methods of mariners' standard behavior for collision avoidance by analyzing mariners' recognition process in a previous study. As a subsequent study, the aim of this study is to build a model of mariners' execution process which is one of six processes in the condition of collision avoidance. In this study, thus, the structure of mariners' information processing on the process of taking avoiding actions is described and the relation between mariners' behavior and necessary factors in the process is analyzed. And then we have built a model of mariners' standard behavior for execution process based on the characteristics of mariners in ship-handling, which are obtained from the international collaborative research on human factors. It is tried to define the contents of execution process based on the standard behavior of mariners for collision avoidance and to formulate information processing of mariners.

The Combination of Bacillus natto JLCC513 and Ginseng Soluble Dietary Fiber Attenuates Ulcerative Colitis by Modulating the LPS/TLR4/NF-κB Pathway and Gut Microbiota

  • Mingyue Ma;Yueqiao Li;Yuguang He;Da Li;Honghong Niu;Mubai Sun;Xinyu Miao;Ying Su;Hua Zhang;Mei Hua;Jinghui Wang
    • Journal of Microbiology and Biotechnology
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    • v.34 no.6
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    • pp.1287-1298
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    • 2024
  • Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that is currently difficult to treat effectively. Both Bacillus natto (BN) and ginseng-soluble dietary fiber (GSDF) are anti-inflammatory and helps sustain the intestinal barrier. In this study, the protective effects and mechanism of the combination of B. natto JLCC513 and ginseng-soluble dietary fiber (BG) in DSS-induced UC mice were investigated. Intervention with BG worked better than taking BN or GSDF separately, as evidenced by improved disease activity index, colon length, and colon injury and significantly reduced the levels of oxidative and inflammatory factors (LPS, ILs, and TNF-α) in UC mice. Further mechanistic study revealed that BG protected the intestinal barrier integrity by maintaining the tight junction proteins (Occludin and Claudin1) and inhibited the LPS/TLR4/NF-κB pathway in UC mice. In addition, BG increased the abundance of beneficial bacteria such as Bacteroides and Turicibacter and reduced the abundance of harmful bacteria such as Allobaculum in the gut microbiota of UC mice. BG also significantly upregulated genes related to linoleic acid metabolism in the gut microbiota. These BG-induced changes in the gut microbiota of mice with UC were significantly correlated with changes in pathological indices. In conclusion, this study demonstrated that BG exerts protective effect against UC by regulating the LPS/TLR4/NF-κB pathway and the structure and metabolic function of gut microbiota. Thus, BG can be potentially used in intestinal health foods to treat UC.

Exploration of the Direction for the Practice of Process-Focused Assessment (과정 중심 평가의 실행을 위한 방향 탐색)

  • Lee, Kyeong-Hwa;Kang, Hyun Young;Ko, Eun-Sung;Lee, Dong-Hwan;Shin, Bomi;Lee, Hwan Chul;Kim, Sun Hee
    • Journal of Educational Research in Mathematics
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    • v.26 no.4
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    • pp.819-834
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    • 2016
  • As a method to lead a change in mathematics education, recently reformation of assessment appears as a concept of process-focused assessment. Process-focused assessment is the concept that 2015 revised mathematics curriculum aims for, which is promoted also in policy. This research suggested a significance of process-focused assessment that has not been determined in conceptualization and the practical model. For this, this research investigated the content of the assessment on 2015 revised mathematics curriculum, and explored process-focused assessment based on the recent education assessment theory and research. Also, we suggested a model of practical plan by investigating the condition to perform the process-focused assessment. This research could take a basic role to practice process-focused assessment and investigate the concrete plan in the mathematics class field.