• Title/Summary/Keyword: Interest Stability

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A design study of carbody with side-buffer (Side Buffer가 적용된 차량의 설계 고찰)

  • Kwon, Seung-Yeol;Kwak, Tae-Ho;Jeon, Si-Heon
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.1618-1623
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    • 2009
  • In this paper, we describe the design method of carbody structure with side-buffer. Recently railroad industry has a new interest with stability, fixed time, low environment pollution and mass transportation. Accidents have little on the railroad but railroad industry is trying to minimize carbody damage and passenger injury in case of accidents. So a side-buffer having anti-climber is applied to meet each special needs. Carbody with side-buffer is assembled with aluminum(6005A-T6) parts that are extruded. As the results of the study, it is showed that carbody with side-buffer has sufficient energy absorbtion about crashworthiness.

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Functional Inks for Printed Electronics

  • Choi, Young-Min;Jeong, Sun-Ho
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.63.1-63.1
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    • 2012
  • In recent years, the functional inks for printed electronics that can be combined with a variety of printing techniques have attracted increasingly significant interest for use in low cost, large area, high performance integrated electronics and microelectronics. In particular, the development of solution-processable conductor, semiconductor and insulator materials is of great importance as such materials have decisive impacts on the electrical performance of various electronic devices, and, therefore, need to meet various requirements including solution processability, high electrical performance, and environmental stability. Semiconductor inks such as IGO, CIGS are synthesized by chemical solution method and microwave reaction method for TFT and solar cell application. Fine circuit pattern with high conductivity, which is valuable for flexible electrode for PCB and TSP devices, can be printed with highly concentrated and stabilized conductor inks such as silver and copper. Solution processed insulator such as polyimide derivatives can be use to all printed TFT device. Our research results of functional inks for printed electronics provide a recent trends and issues on this area.

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Railway carbody analysis technology development for application Europe crashworthiness standard. (유럽 충돌안전도 규격 적용 철도차량 차체 해석 기술 개발)

  • Jeong, Ji-Ho;Park, Hyung-Soon;Park, Guen-Soo;Lee, Jang-Wook
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.231-237
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    • 2006
  • Recently railroad industry pulls a new interest with stability, fixed time characteristic, low environment pollution characteristic and mass transportation characteristic. With industrial development railroad it joins in, The many research and regulation production are coming to do. Specially like this activities are coming to be advanced actively from North America and Europe. From viewpoint of railway car production company, The vehicle production that a suitable Europe standard is essentiality for find a Europe market that The whole vehicle consuming hold it does a most big specific gravity. From this study, developed finite element model for analysis technology about crashworthiness of inside GM/RT 2100 standard and analyzed crash results.

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Bending Strength and Microstructure of Cement Paste Containing SWCNT Dispersion Solution (SWCNT 분산용액을 혼입한 시멘트 페이스트의 휨강도 및 미세구조)

  • Choi, Ik-Je;Kim, Ji-Hyun;Lee, Soo-Yong;Chung, Chul-Woo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2017.11a
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    • pp.149-150
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    • 2017
  • It is known that physical and chemical changes of cement hydrates cause problems in the volume stability of concrete. In order to overcome these problems, there is a growing interest in research on mixing technology of cement-based materials and nanomaterials. Among the nanomaterials, carbon nanotubes (CNTs) are attracting attention due to their excellent mechanical properties. The CNTs are made of cylindrically shaped graphene sheets. According to the number of sheets, single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) are classified. Although the SWCNT has superior mechanical properties, the research using MWCNT is vigorous due to the difficulty of marketability and manufacturing, but the research using SWCNT is insufficient. In this study, we investigate the effect of SWCNT on the formation of hydrate of cement paste by observing the microstructure of broken cement paste after measuring the flexural strength of cement paste with SWCNT dispersion.

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Effect of the Pressure Formation at the Tip of the Melt Delivery Tube in Close-coupled Nozzles in Gas Atomization Process

  • Unal, Rahmi
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.477-478
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    • 2006
  • Close-coupled atomizers are of great interest and controlling their performance parameters is critical for metal powder producing and spray forming industries. In this study, designed close-coupled nozzle systems were used to investigate the effect of the nozzle types and protrusion length of the melt delivery tube on the pressure formation at the melt delivery tube tip. The observed metal flow rate was not behaving as what was earlier assumed, namely that, deeper aspiration enhanced metal flow rate. Higher aspiration pressure at the tip of the melt delivery tube increases the stability of atomization process.

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DC-Voltage Regulation for Solar-Variable Speed Hybrid System

  • Niyitegeka, Gedeon;Lee, Kyungkyu;Choi, Jaeho
    • Proceedings of the KIPE Conference
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    • 2015.11a
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    • pp.123-124
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    • 2015
  • Recently interest on DC systems has been grown up extensively for more efficient connection with renewable energy. During the operation, there happens DC_link voltage variations. This paper focuses on the DC voltage stabilization applied in stand-alone DC microgrid to improve the system stability by keeping the voltage within limits. Batteries and a variable speed diesel generator cover the shortage of power after all available renewable energy is consumed. Load shedding or power generation reduction should automatically takes place if the maximum tolerable voltage variation is exceeded. PSIM based simulation results are presented to evaluate the performance of the proposed control measures.

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Nutritive Value and Functional Properties of Protein Concentrate Fractionated from Chrysanthemum Flowers

  • Park, Nan-Young;Park, Yong-Jin;Kwon, Joong-Ho
    • Preventive Nutrition and Food Science
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    • v.3 no.2
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    • pp.175-179
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    • 1998
  • Some functional properties and nutritive value were determined for the protein concentrated fractionated from chrysanthemum flower in orer to renew interest in the flowers as food. Proximate components of chrysanthemum flower protein concentration (FPC) showed 61.2% protein, 2.0% fat and 35.2% carbhydrate on a dry basis. In amino acid composition of FPC, glutamic acid was the highest in the content, follwoed by aspartic acid, leucine and lysine. The ratio of essential/ total amino acids(E/T) was 0.42, showing a higher level of essential amino acids compared to the FAO reference protein. Digestibility of chrysanthemum FPC by pepsin and trypsin was lwoer than that of casein and was negatively correlative to both water and fat absorptions. Similar characteristics were determined between chrysanthemum FPC and milk casein in their emulsifying activity and emulsion stability. This results indicate that flowers or petals of chrysanthemum might be developed as a good source of protein.

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Treatment of an Atrophic Scar with Fractional Carbon Dioxide Laser-assisted Poly-L-lactic Acid Delivery

  • Kim, Wan Jin;Jung, Ha Rin;Lee, Sang Ju;Cho, Han Kyoung
    • Medical Lasers
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    • v.10 no.3
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    • pp.181-184
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    • 2021
  • Scars can cause great psychological stress among patients. Currently, there are numerous topical agents, laser and surgical treatments available for skin rejuvenation and scar minimization. Laser-assisted drug delivery (LADD) is a treatment method that increases drug delivery by stimulating the skin physically and chemically to enhance the penetration of topical agents. This is one of the areas of great interest in the treatment of various skin diseases in addition to its use for cosmetic purposes. In particular, LADD is relatively non-invasive and has advantages in terms of accessibility and stability. Poly-L-lactic acid (PLLA) is a collagen stimulator known to gradually restore skin volume by inducing inflammation and fibroplasia. Herein, we report a case of treatment of an atrophic scar with fractional carbon dioxide laser-assisted PLLA delivery.

Transition-metal oxalate-based electrodes for alkaline water electrolysis : a review (전이금속 옥살산염 기반 알칼라인 수전해 전극 응용기술 동향)

  • Ha, Jaeyun;Kim, Yong-Tae;Choi, Jinsub
    • Journal of the Korean institute of surface engineering
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    • v.55 no.2
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    • pp.38-50
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    • 2022
  • As a low-cost and high-efficiency electrocatalysts with high performance and stability become a key challenge in the development of the practical use of water electrolysis, there is an intense interest in transition-metal oxalate-based materials. Transition-metal oxalate-based catalysts with excellent electrochemical performances have been widely applied in water electrolysis due to its low-cost and ease of synthesis. This review provides a useful summary on the development of transition-metal oxalate as potential catalysts for water electrolysis with a focus on the structural and compositional alteration, role of oxalate anion, and enhanced electrochemical performances.

Spore-Pollen Specters of Deed Turnn Lake Terrace, Darkhad Depression, Mongolia

  • Punsalpaamuu, G.
    • The Korean Journal of Quaternary Research
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    • v.17 no.2
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    • pp.39-41
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    • 2003
  • Pollen and spores as well as their morphological characteristics are biological stability materials in which contains historical information about vegetation and climate changes. As noted researcher Neishtadt in 1971, the lake and swamp deposits were developed only in Holocene period. The geological history of Darkhad depression which is situated in the Northern end of Mongolia from ancient time become under scientific interest of many researchers. Our investigation was focused on pollen analysis of lake sediment of Darkhad depression which caused bottom of paleolake. In Mongolia the palynology science is beginning to develop since 1990 and in 2000 the laboratory of palynology was established at the department of Biology, State Pedagogical University of Mongolia. Researchers from this laboratory working on pollen morphology of present flora in order to classify plants taxonomy. Another part of our investigation is mellitopalynology, which is studying of pollen grains in a honey. Although, this research has been extending by pollen analysis of sediment and lake deposits in past few years on the basis of high sensitive microscope and modem technology.

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