• Title/Summary/Keyword: Widening process

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Study on Design Education Plan Using Microcontroller Board Prototyping Tool

  • Nam, Wonsuk
    • International Journal of Contents
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    • v.14 no.3
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    • pp.61-68
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    • 2018
  • Unlike in the past, where the expression of the form was given a priority, with the widening of the scopes of the designs, the proportion of design education institution curricula targeting user experience and the application of technology is continually and gradually increasing. Open source microcontroller boards such as Arduino have initiated attracting attention as a countermeasure against these changes. These prototyping tools have many advantages for the diversification of expression and design verification in the design field and therefore have a high likelihood of being introduced into many design education institutes; however, the tools act as high entry barriers for design students who lack engineering knowledge. Although various educational content and tools have been developed to address the issue of barrier, existing solutions remain insufficient as alternatives for the purpose of activation. In this study, we investigated the present state of related education content and conducted a pilot workshop using a prototype microcontroller board with simplified coding. We intend to use the results of this investigation to develop study material for design education. We started by conducting a survey regarding the pre-university education situation. It was observed that engineering education opportunities are insufficient and the problem of mutual application between educations due to course-based education was not realized. We also analyzed the characteristics of simplified training tools using the microcontroller to establish a direction for educational design and conducted a pilot workshop using the microcontroller toolkit with a simplified coding process based on this content. Students who lack a basic knowledge of engineering technology received instruction, and after completing minimum preliminary training, they proceeded to practical exercises that involved utilizing the toolkit. Through this process, we identified the need for a simple-type microcontroller board with low-complexity for use in educating students majoring in design. We also identified some obstacles that serve as barriers to entry of utilizing microcontroller board. Based on these results, we propose several functional requirements and teaching guidelines for prototyping toolkits for design education.

Fabrication of Photo Sensitive Graphene Transistor Using Quantum Dot Coated Nano-Porous Graphene

  • ;Lee, Jae-Hyeon;Choe, Sun-Hyeong;Im, Se-Yun;Lee, Jong-Un;Bae, Yun-Gyeong;Hwang, Jong-Seung;Hwang, Seong-U;Hwang, Dong-Mok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.658-658
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    • 2013
  • Graphene is an attractive material for various device applications due to great electrical properties and chemical properties. However, lack of band gap is significant hurdle of graphene for future electrical device applications. In the past few years, several methods have been attempted to open and tune a band gap of graphene. For example, researchers try to fabricate graphene nanoribbon (GNR) using various templates or unzip the carbon nanotubes itself. However, these methods generate small driving currents or transconductances because of the large amount of scattering source at edge of GNRs. At 2009, Bai et al. introduced graphene nanomesh (GNM) structures which can open the band gap of large area graphene at room temperature with high current. However, this method is complex and only small area is possible. For practical applications, it needs more simple and large scale process. Herein, we introduce a photosensitive graphene device fabrication using CdSe QD coated nano-porous graphene (NPG). In our experiment, NPG was fabricated by thin film anodic aluminum oxide (AAO) film as an etching mask. First of all, we transfer the AAO on the graphene. And then, we etch the graphene using O2 reactive ion etching (RIE). Finally, we fabricate graphene device thorough photolithography process. We can control the length of NPG neckwidth from AAO pore widening time and RIE etching time. And we can increase size of NPG as large as 2 $cm^2$. Thin CdSe QD layer was deposited by spin coatingprocess. We carried out NPG structure by using field emission scanning electron microscopy (FE-SEM). And device measurements were done by Keithley 4200 SCS with 532 nm laser beam (5 mW) irradiation.

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A Study on the Method of Ecological Restoration at the Abandoned Expressways - Focusing on the 192.4k(Incheon) Young-Dong Expressway - (폐고속국도의 생태복원 방안 -영동선 192.4K(인천) 지점을 중심으로-)

  • Cho, Dong-Gil;Choi, Jae-Yong;Jeon, Young-Chul
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.13 no.5
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    • pp.38-50
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    • 2010
  • Expressways are often upgraded by widening the lanes and/or by reshaping the roads to be more linear for faster travel time. However, during the process of improving the route of the expressways, the areas where the old expressways used to be are often unused and abandoned. When these neglected sites are left alone, they often become dump sites causing pollution and impacting the surrounding environment. Therefore, it is important to restore the abandoned expressway sites to its full natural beauty. In this study, the abandoned expressway at the Soksa interchange in Pyungchang county, located in Kangwon province was studied for establishing the model of ecological restoration project. Considering the characteristics of the site, the target flora species was chosen to be Quercus species and the target fauna species as amphibians. After the target species were carefully chosen, each species' habitat requirements were studied in order to figure out the appropriate methods toward habitat restoration specifically for these species. In addition, to determine the most efficient method toward restoration of abandoned expressways, the study utilized the planting hole techniques, the crack techniques, and the colonization techniques. In terms of the spatial organization, public education program is incorporated at the main entrance area and the programs for experimenting, and developing vegetation and habitat restoration techniques are placed in the vicinity. In the master plan-to provide natural ecosystem at the site-ASCON (asphalt concrete) was removed first, then plans for restoration including species' habitat restoration were established. Furthermore, the project included plans for improving water quality polluted through non-point source considering the surrounding nearby road and farm lands. Finally, the study established a planning process that will experimentally apply to the abandoned expressway restoration method. In the future, there will be a continuous monitoring of the methods applied to verify if the restoration methods are effective. Also, new restoration techniques should be available according to a variety of abandoned expressways' characteristics.

Mechanical Properties of PVB 3D Printed Output Fumigated with Ethanol (에탄올 훈증처리한 3D 프린팅 PVB 출력물의 기계적 특성)

  • Kang, Eun-Young;Lim, Ji-Ho;Choi, Seunggon;Mun, Jong Wook;Lee, Yu Kyung;Lee, Sun Kon;Jeong, Dae-Yong
    • Korean Journal of Materials Research
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    • v.30 no.7
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    • pp.369-375
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    • 2020
  • FDM 3D printing structures have rough surfaces and require post-treatment to improve the properties. Fumigation is a representative technique for removing surface unevenness. Surface treatment by fumigation proceeds by dissolving the surface of the protruding structure using a vaporized solvent. In this study, 3D printed PVB outputs are surface-treated with ethyl-alcohol fumigation. As the fumigation time increases, the surface flattens as ethanol dissolves the mountains on the surface of PVB and the surface valleys are filled with dissolved PVB. Through the fumigation process, the mechanical strength tends to decrease, and deformation rate increases. Ethanol vapor permeates into PVB, widening the distance between chains and resulting in weak bonding strength between chains. In order to confirm the effect of fumigation only, an annealing process is performed at 80 ℃ for 1, 5, 10, 30, and 50 minutes and the results of the fumigation are compared.

Computational Analysis of the Effects of Spray Parameters and Piston Shape on Syngas-Diesel Dual-Fuel Engine Combustion Process

  • Ali, Abubaker Ahmed M.M.;Kabbir, Ali;Kim, Changup;Lee, Yonggyu;Oh, Seungmook;Kim, Ki-seong
    • Journal of ILASS-Korea
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    • v.23 no.4
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    • pp.192-204
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    • 2018
  • In this study, a 3D CFD analysis method for the combustion process was established for a low calorific value syngas-diesel dual-fuel engine operating under very lean fuel-air mixture condition. Also, the accuracy of computational analysis was evaluated by comparing the experimental results with the computed ones. To simulate the combustion for the dual-fuel engine, a new dual-fuel chemical kinetics set was used that was constituted by merging two verified chemical kinetic sets: n-heptane (173 species) for diesel and Gri-mech 3.0 (53 species) for syngas. For dual-fuel mode operations, the early stage of combustion was dominated by the fuel burning inside or near the spray plume. After which, the flame propagated into the syngas in the piston bowl and then proceeded toward the syngas in the squish zone. With the baseline injection system and piston shape, a significant amount of unburned syngas was discharged. To solve this problem, effects of the injection parameters and piston shape on combustion characteristics were analyzed by calculation. The change in injection variables toward increasing the spray plume volume or the penetration length were effective to cause fast burning in the vicinity of TDC by widening the spatial distribution of diesel acting as a seed of auto-ignition. As a result, the unburned syngas fraction was reduced. Changing the piston shape with the shallow depth of the piston bowl and 20% squish area ratio had a significant effect on the combustion pattern and lessened the unburned syngas fraction by half.

Faulkner's Narrative Strategies and the Nature of History in Absalom, Absalom!

  • Rhee, Beau La
    • Journal of English Language & Literature
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    • v.56 no.6
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    • pp.1091-1103
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    • 2010
  • Absalom, Absalom! is not only about family history but also about the nature of reconstructing history. Faulkner shows us what will happen if we give too much credit to the person having the authority; he first makes us listen to Rosa, so we just listen without doubt until we arrive at the question of the objectivity of her narration, when we get to know Sutpen's design. Meanings of "facts" change depending on who perceives the facts. The incremental repetition of the narrative in the novel resembles the process of our thinking mind and the process of history being constructed. Time is a significant element in determining the meaning of an event, not only because the event cannot be understood without its social, cultural context of the contemporary, but also because only the later events make it possible for the perceiver to categorize it in its proper place in history. Furthermore, through his narrative strategy, Faulkner suggests that imagination play a large part in recreating history. He blurs the distinction between facts and imagination, making us regard Shreve's and Quentin's conjectures as facts in several ways. The conversation between father and son, and the two brothers, which is an imagination constructed through the clues Mr Compson has offered, becomes a fact willingly accepted by the readers as well as Shreve and Quentin. The people in the past, present, and future may be very much unlikely to agree on the same event, because the gap in temporality will keep widening our perceptions. Faulkner demonstrates the nature of history in such a way that we can compare our understanding of the Sutpens' history in the earlier and later part of the novel through repetitions.

Shape Improvement and Optimum Gradation of Dry Processed Bottom Ash for Lightweight Mortar (경량 모르터용 건식공정 바텀애시의 입형 개선 효과와 최적 입도)

  • Choi, Hong-Beom;Kim, Jin-Man;Sun, Jung-Soo;Han, Dong-Yeop
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.3 no.1
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    • pp.7-14
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    • 2015
  • The aim of this research is suggesting dry processed bottom ash as a new and economical source of lightweight aggregate for mortar and concrete. The dry process of bottom ash is an advance method of water-free and no chloride because only cooled down by double dry conveyer belt systems. Furthermore, because of relatively slow cooling down process helps burning up the remaining carbon in bottom ash. Using this dry process bottom ash, to evaluate the feasibility of using as a lightweight aggregate for mortar and concrete, two-phase of experiments were conducted: 1) improving shape of the bottom ash, and 2) controlling grade of the bottom ash. From the first phase of experiment, additional abrasing process was conducted for round shape bottom ash, hence improved workability and compressive strength was achieved while unit weight was increased comparatively. Based on the better shape of bottom ash, from the second phase, various grades were adopted on cement mortar, standard grade showed the most favorable results on fresh and hardened properties. It is considered that the results of this research contribute on widening sustainable method of using bottom ash based on the dry process and increasing value of bottom ash as a lightweight aggregate for concrete.

Comparison of Normalization Methods for Defining Copy Number Variation Using Whole-genome SNP Genotyping Data

  • Kim, Ji-Hong;Yim, Seon-Hee;Jeong, Yong-Bok;Jung, Seong-Hyun;Xu, Hai-Dong;Shin, Seung-Hun;Chung, Yeun-Jun
    • Genomics & Informatics
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    • v.6 no.4
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    • pp.231-234
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    • 2008
  • Precise and reliable identification of CNV is still important to fully understand the effect of CNV on genetic diversity and background of complex diseases. SNP marker has been used frequently to detect CNVs, but the analysis of SNP chip data for identifying CNV has not been well established. We compared various normalization methods for CNV analysis and suggest optimal normalization procedure for reliable CNV call. Four normal Koreans and NA10851 HapMap male samples were genotyped using Affymetrix Genome-Wide Human SNP array 5.0. We evaluated the effect of median and quantile normalization to find the optimal normalization for CNV detection based on SNP array data. We also explored the effect of Robust Multichip Average (RMA) background correction for each normalization process. In total, the following 4 combinations of normalization were tried: 1) Median normalization without RMA background correction, 2) Quantile normalization without RMA background correction, 3) Median normalization with RMA background correction, and 4) Quantile normalization with RMA background correction. CNV was called using SW-ARRAY algorithm. We applied 4 different combinations of normalization and compared the effect using intensity ratio profile, box plot, and MA plot. When we applied median and quantile normalizations without RMA background correction, both methods showed similar normalization effect and the final CNV calls were also similar in terms of number and size. In both median and quantile normalizations, RMA backgroundcorrection resulted in widening the range of intensity ratio distribution, which may suggest that RMA background correction may help to detect more CNVs compared to no correction.

Extending the Self-ordering Regime of High-field Anodization by Using an Electrolyte Additive (전해액 첨가제를 이용한 고전계 양극산화의 자기정렬에 관한 연구)

  • Kim, Min-Woo;Park, Seong-Soo;Sim, Seong-Ju;Kang, Tae-Ho;Shin, Yong-Bong;Ha, Yoon-Cheol
    • Journal of the Korean Electrochemical Society
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    • v.14 no.4
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    • pp.219-224
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    • 2011
  • Using an electrolyte additive, we examined, for the first time, a novel self-ordering regime of 160~200 V in high-field anodization which had been used for a fast fabrication of self-ordered anodic alumina nanotemplate. FE-SEM analyses conducted after the high-field anodization, pulse detachment and chemical widening of pores showed the relationship of 2.2 nm/V in this voltage range, which was identical to the previously reported one in the literature. The growth rate of the alumina film was about 60 um/hr, which was 30 times faster than that of phosphoric acid mild anodization. This study provides a new process for the fast fabrication of nanotemplates with interpore distances larger than 300 nm.

A Field Study on the Present Situation, Tasks and Policies of E-business in Kangwon Province (강원지역 e-비즈니스 현황과 발전과제)

  • Min, Nam-Sik
    • Korean Business Review
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    • v.17
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    • pp.185-214
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    • 2004
  • This paper is focused on the e-business level in Kangwon Province by industries, volumes, employees comparing with nation wide survey output, and analysis of the tasks and problems of e-business in environment, infrastructure, process, manpower, effect. Poor level of Kangwon province was identified. It is important that role clarity and cooperation among central goverment, Kangwon province, large enterprises and small and medium enterprises. Local goverment and regional cities and counties should play a centripetal role of the regional enterprises, and faithfully execute the support policies of the central goverment, and make the unique supporting climate of coopration between the university and enterprises in consideration with situations of each regional characteristics. More specifically, there are widening the infrastructure of e-business for regional enterprises, strenthening educatin and public relation of the electronic commerce, supporting and utilizing the electronic ccommerce research center. Also, fund supporting for SOHO is desirable in consideration of the poor Kangwon land and population, and to enhence the electronic commerce technology of the Kangwon enterprises, relative importance of policy of it is incresing. In conclusion, indices of Kangwon province in all areas of the survey is appeared poor. So efficient and effective policies is needed in each central and regional goverment. To promote Kangwon enterprises, investment in e-business commerce should be expanded.

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