• 제목/요약/키워드: Commercial medium

검색결과 675건 처리시간 0.028초

중형 상용차용 프레스 성형 차축빔의 경량화 설계 (Structural Design of the Light Weight Axle Beam for Medium Duty Commercial Vehicle Using Hot Press)

  • 심기중;신행우;조원용;최규재;이영춘;손영호;전남진
    • 한국자동차공학회논문집
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    • 제23권4호
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    • pp.371-379
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    • 2015
  • This paper represents the structural design of the light weight axle beam for medium duty commercial vehicle using hot press. To reduce the weight of the axle, axle beam of solid type was replaced by hollow type which was made by hot press. According to the change of axle beam structure and manufacturing method, we have to investigate the structural strength and fatigue performance. To verify the axle beam performance, the structural analysis was carried out by simplified axle beam model and various design parameters that are axle beam height, thickness and width. From the analysis results, the light weight axle beam structure was founded and applied the full model analysis. This study will be used as a guidance in development of the light weight axle for medium duty commercial vehicle.

상용전원 주파수(60Hz)를 사용한 중전력 무선전력전송 연구 (Research on Medium-power Wireless Power Transmission using Commercial Power Frequency (60Hz))

  • 이기범
    • 한국전자통신학회논문지
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    • 제19권3호
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    • pp.497-506
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    • 2024
  • 본 논문에서는 상용전원 주파수(60 Hz)를 사용하여 중전력 무선전력전송을 구현한 것이다. 일반적인 자기유도 무선전력전송 장치는 수십 kHz 이상 사용하기 때문에 상용전원 주파수(60 Hz)를 그대로 사용할 수 없고, 교류/직류 변환기를 사용하여 60 Hz 전원주파수를 DC로 만들고, 고주파 파워앰프를 사용하여 DC를 수십 KHz로 만들어서 사용한다. 자기유도 무선전력전송에서 교류/직류 변환기와 고주파 파워앰프를 제거하고, 송전 공진탱크, 송전코일, 수전 공진탱크, 수전코일 만으로 구성한 상용전원 주파수를 사용하는 극저주파 무선전력전송 시스템을 구현하고, 무선전력전송 실험으로 검증하였다.

귀금속계열 WGS 촉매 연구 (Noble metal catalysts for Water Gas Shift reaction)

  • 임성광;배중면;김선영
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.2228-2231
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    • 2007
  • Water gas shift reactor in fuel processing is an important part that converts carbon monoxide into hydrogen. Fuel processing system for PEMFC usually has two stages of WGS reactors, which are high temperature and low temperature shifter. In this study we prepared noble metal catalysts and compared their performances with that of a commercial iron chromium oxide catalyst. Noble metal catalysts and the commercial catalyst showed quite different temperature dependence of carbon monoxide conversion. The conversion of carbon monoxide at the commercial catalyst was very low at medium temperature(${\sim}300^{\circ}C$) and increased rapidly as temperature increased while the conversion at noble metal catalysts was high in the medium temperature range and decreased as temperature increased, which is thermodynamically expected. Their characteristics agreed well with the literature published, and we are accomplishing further study for improvement of the noble metal catalysts.

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주상복합건물에 대한 면진기술의 적용 (Application of Seismic Isolation Technique in Residential-Commercial Building)

  • 이동근
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2000년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2000
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    • pp.465-472
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    • 2000
  • Seismic isolation technique has been applied mainly in low rise buildings and its seismic performance was satisfactory during Kobe Earthquake. However, in the case of medium and/or high-rise buildings, mid-story isolation could be more technically feasible than base isolation to reduce earthquake forces. In this paper, the seismic effectiveness of mid-story isolation in medium and/or high-rise shear building as well as low rise shear building was evaluated analytically. After verifying the effectiveness of mid-story isolation technique, this method also applied in residential-commercial building. It was found that mid-story isolation, that is isolation between upper residential area and lower commercial area, could reduce inter-story drift and floor shear forces comparing to the conventional fixed base.

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Internet Business Implementation Guidelines for Retailing Using Product Classification Framework

  • Lee, Heeseok;Park, Suyoung;Park, Byounggu
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2001년도 추계학술대회 논문집
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    • pp.91-94
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    • 2001
  • The exponential growth of the Internet usage has motivated the launching of many commercial business web sites. Internet as a purchasing medium shows several unique characteristics because of its customer- driven technologies and absence of physical products. Thus, new commercial medium provokes a reclassification of products. Twenty five types of commercial Products are empirically tested in the Internet retailing and found to be grouped into four categories. This classification framework is investigated in the view of involvement and web technology Furthermore, this paper proposes four business web implementation strategies - impressive, simple, sensory, and semantic - based on the product classification. Proposed guidelines on business web might increase customer satisfaction.

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육묘용 상토내의 폐암면 혼합비율이 메리골드 플러그묘의 생육에 미치는 영향 (Effect of Blending Rate of Waste Rockwool in Nursery Media on Growth of Marygold Plug Seedlings)

  • 전하준;황진규
    • 생물환경조절학회지
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    • 제16권1호
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    • pp.27-31
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    • 2007
  • 수경재배의 폐암면 처리문제를 해결하고 수입의존도가 높은 육묘용 상토 자재의 개발로 육묘산엽의 발전에 기여하고자 폐암면의 혼합비율을 달리한 플러그용 육묘상토를 조성하여 메리골드의 생육에 대한 효과를 조사하였다. 시판 육묘상토를 대조구로 하고, 시판 육묘상토에 이용되는 코코피트 대신에 폐암면을 10, 30, 50%로 혼합하여 혼합상토를 조제하여 50공 트레이에 파종하고 생육조사를 실시하였다. 메리골드의 발아율은 처리구간에 유의한 차이를 나타내지 않았다. 초장, 엽수, 경경, 엽면적과 지상부 및 지하부의 건물중 및 생체중은 시판상토와 폐암면 50% 혼합 처리구에서 양호하였다. 그러나 폐암면 30 및 10% 혼합처리구에서는 시판상토에 비해서 생육이 낮았는데 그 결과에 대해서는 정확한 원인을 밝힐 수 없었다. 본 실험에서는 폐암면을 플러그용 육묘상토의 자재로서 충분히 활용할 수 있다는 가능성을 보여 주었으며, 폐암면의 적정한 혼합비율에 대해서는 계속적인 실험이 필요한 것으로 생각되었다.

Evaluation of a Chromogenic Medium Supplemented with Glucose for Detecting Enterobacter sakazakii

  • Song, Kwang-Young;Hyeon, Ji-Yeon;Shin, Ho-Chul;Park, Chan-Kyu;Choi, In-Soo;Seo, Kun-Ho
    • Journal of Microbiology and Biotechnology
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    • 제18권3호
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    • pp.579-584
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    • 2008
  • A commercial chromogenic agar medium (DFI) was supplemented with glucose (mDFI) to enhance the specificity of Enterobacter sakazakii (E. sakazakit) detection. Escherichia vulneris (E. vulneris), a putative false-positive strain on the DFI medium, produces ${\alpha}$-glucosidase. The enzyme ${\alpha}$-glucosidase hydrolyzes a substrate, 5-bromo-4-chloro-3-indolyl-${\alpha}$, D-glucopyranoside $(X{\alpha}Glc)$, producing green colonies. E. sakazakii strains produced green colonies on both DFI and mDFI agar, whereas E. vulneris produced green colonies on DFI agar but small white colonies on mDFI agar. E. sakazakii and E. vulneris were also readily differentiated by colony color when the mixed culture of the two strains was plated on mDFI agar and incubated for 24 h at $37^{\circ}C$. The results indicate that the selectivity of the commercial chromogenic agar medium could be improved by a simple supplementation with glucose.

구연산 발효에 관한 연구 (제 2 보) 국산 포도당을 기질로하고 Asp. niger에 의한 발효 (Studies on the Citric Acid Fermentation (Part 2) The Citric Acid Fermentation by Asp. niger, as the Substrate of Local Commercial Glucose)

  • 이상선;박무영
    • 한국미생물·생명공학회지
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    • 제6권4호
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    • pp.167-171
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    • 1978
  • 전보에 개발된 배지에 국산 포도당을 이용한 발효결과, 구연산 생성은 37∼43g/ι이었다. 제품X의 경우는 제품Y에 비해 구연산 생성이 우수하여 43g/ι가 생성되었다. 국산 포도당을 Ambelite-IR -120으로 처리하고, peptone도 potassium ferrocyan-ide로 처리하여 금속이온을 제거한 뒤에, 10mg/ι의 철 이온을 첨가하였을 때 구연산 생성은 53gm/ι에 달하였다. 또한 원래 Sakaguchi 배지에 비해 3배나 많이 구연산이 생성되었다. 분리 동정된 Asp. niger를 다른 문헌과 비교하였을 때 큰 손색이 없었으며, 앞으로의 생리연구 및 mutation 연구가 필요하겠다.

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Comparison of Bifidobacteria Selective Media for the Detection of Bifidobacteria in Korean Commercial Fermented Milk Products

  • Kim, Eung-Ryool;Cho, Young-Hee;Kim, Yong-Hee;Park, Soon-Ok;Woo, Gun-Jo;Chun, Ho-Nam
    • 한국축산식품학회지
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    • 제30권1호
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    • pp.154-162
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    • 2010
  • This study was carried out to compare the efficacy and selectivity of TOS and BS media for enumeration of bifidobacteria in commercial fermented milk products. First, bifidobacteria was isolated from 20 fermented milk products, and all isolated bifidobacteria were identified by genomic technology as Bifidobacterium lactis. The two media significantly differed from each other with regard to the recovery of B. lactis, that is, the recovery of this organism was as much as 6 logs lower on BS medium than on TOS. When the concentration of BS solution (mixture of paromomycin sulfate, neomycin, sodium propionate, and lithium chloride) used in BS medium was reduced to 50% (BS50), a relatively high percentage recovery of bifidobacteria from pure cultures was achieved. Susceptibility tests to antibiotics and tests for selective agents for the isolated bifidobacteria and lactic acid bacteria were conducted. The BS solution inhibited some lactic acid bacteria and Bifidobacterium species, while mupirocin (MU) suppressed the growth of all tested lactic acid bacteria but not Bifidobacterium. As compared with BS50 medium, TOS with or without MU showed good bifidobacteria recovery and readily distinguishable colonies; in particular, TOS supplemented with MU had a high selectivity for bifidobacteria. In conclusion, all results suggested that TOS medium with or without MU was found to be suitable for selective enumeration of bifidobacteria from mixed cultures in fermented milk, and better in that capacity than BS medium.

지렁이 분립을 첨가한 유기상토가 벼의 유식물체 생육에 미치는 영향 - 톱밥발효 돈분으로 생산한 분립의 첨가 - (Effect of Commercial Organic Medium Amended with Vermicast on the Growth of Rice Seedlings(Oryza sativa L.) -Amended with Vermicast of Fermented Pig Manure with Sawdust-)

  • 이주삼;김인수
    • 한국유기농업학회지
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    • 제16권3호
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    • pp.299-308
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    • 2008
  • 유기상토에 툽밥 발효 돈분으로 생산한 분립의 첨가비율을 달리했을 때, 벼의 유식물체 생육에 미치는 영향을 조사하였다. 저면도포 무처리구에서 추청 벼는 분립 20%까지의 혼합비율, 흑미 벼는 분립 10%까지의 첨가비율에서 유식물체의 생육이 양호하였다. 또한 저면도포 처리구에서는 추청 벼와 흑미벼 모두 분립 5% 혼합비율에서 유식물체의 생육이 양호하였다. 저면도포 처리구가 무처리구에 비하여 낮은 분립 첨가비율에서 유식물체의 생육이 양호하였던 것은 뿌리신장에 의하여 토양표면에 시용된 분립으로부터 생육에 필요한 양분의 공급이 이루어졌기 때문으로 추정된다. 또한 장기간 벼를 육묘할 경우에는 유식물체의 생육이 양호하였던 분립의 적정 혼합비율의 범위가 갖는 상토의 이화학성의 유지가 필요하다고 판단된다. 지렁이 분립의 이화학적 특성으로 볼 때, 유기 경종농업에서 토양시용 또는 상토재의 원료로서 유용하게 활용될 수 있을 것으로 판단된다.

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