• 제목/요약/키워드: Technical Index

검색결과 627건 처리시간 0.028초

변조지수가 2/3인 PCM/FM (PCM/FM With Modulation Index of 2/3)

  • 구영모
    • 한국항공우주학회지
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    • 제49권11호
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    • pp.941-944
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    • 2021
  • 텔레메트리 분야에서 많이 사용되는 PCM/FM은 변조지수가 0.7인데 이를 2/3로 변경하면 3-PSK로 해석이 가능하며 위상 변화 트렐리스 상태수가 3이 되어 간단한 비터비 복호기로 수신이 가능하다. 컴퓨터 모의실험한 결과 AWGN 채널에서 Eb/No 수신 성능은 BER이 10-5일 때 약 8.3dB로 이론적 한계값에 근접한다.

대공간 막 구조물 지붕의 수밀성능 확보를 위한 유지관리 지표 연구 (Technical Index for the Maintenance of Watertightness of the Roof of a Large-Span Membrane Structure)

  • 오상근;김동범;이선규
    • 한국건축시공학회지
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    • 제11권1호
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    • pp.51-59
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    • 2011
  • 최근 막 구조물의 수요 증가에 따라 막 구조물의 구조 및 재료적 연구의 진행은 막 구조물을 하나의 독립된 구조물로써 인정받을 만큼 활발히 진행되고 있지만, 유지 관리 측면의 연구의 경우 아직까지 이에 미치지 못한 상황이다. 특히 유지관리 측면에의 연구 중 지붕구조의 수밀성 및 누수에 관한 연구는 해외에서 일부만을 다루고 있어 국내 실정에 맞는 유지관리 지표 개발이 요구되고 있다. 이에 본 연구에서는 막 구조물 지붕부의 막재 및 접합부, 지붕 형태에 따른 누수취약부에 대해서의 하자 사례 조사를 통하여 누수 요인 및 열화 인자를 분석하였고, 이를 AHP기법을 활용하여 중요도를 부여하여, 막 구조물에서 필요한 유지관리 지표를 제안하였으며, 이를 바탕으로 막 구조물 지붕의 장기적으로 수밀성 확보를 위한 설계 및 시공단계서의 수밀성 평가 지표, 준공 후 사용과정에서의 점검 관리 지표를 제안하였다.

Ganoderma lucidum균 전처리를 이용한 볏짚의 상압.소다펄프화

  • 주용찬;강진하
    • 펄프종이기술
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    • 제34권4호
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    • pp.51-60
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    • 2002
  • This study was carried out to develop the biochemical pulping method to enhance energy saving and decrease the capital cost through the soda pulping under atmospheric pressure (100%). Nonwood substrates, rice straw, were pretreated by white-rot fungi, Ganoderma Iucidum. It has acquired several basic data that can be applied in bio-soda pulping. The results of this study were as follow. Without any nutrients or with glucose, N and glucose+N the weight losses of rice straws inoculated by Canoderma Iucidum were 8.5~29.8%, 9.3~32% 11.8~30.1% and 11.8~24.4% respectively for 5, 10, 15, 20, 25 and 30 days incubation. The more extending incubation periods, the more increasing weight losses. The yield of untreated rice saw was 54.8% after pulping. When any nutrients was not added or glucose, N and glucose+N were added for the pretreatment, the total yields were ranged 50.6~38.5%, 48.6~34.4%, 47.2~38.4% and 49.5~42.6% respectively for 5, 10, 15, 20, 25 and 30 days incubation. The yields were gradually decreased based on extending of incubation. The physical properties of rice straw soda pulps without fungal treatment, the density, breaking length, burst index, tear index and folding endurance were 0.24 g/$\textrm{cm}^3$, 2.32 km, 0.91 kPa $m^2$/g, 56.7 mN.$m^2$/g and 35 times, respectively. After pretreatment without any nutrients or with glucose, N and glucose+N as nutrients the density was 0.27~0.30 g/$\textrm{cm}^3$, the breaking length 3.14~5.25 km, burst index 1.42~2.78 kPa.$\textrm{m}^2$/g, tear index45.8~64.5 mN.$\textrm{m}^2$/g and folding endurance 47~288 times at all incubating periods when pulping was done. The physical properties were increased with the increasing incubation periods. However, when glucose+N was added, the physical properties were shown superior results each incubating duration.

골판지 고지의 물리화학적 처리에 의한 강도향상(제3보) - 수초지의 물리적 특성변화 - (Strength Property Improvement of OCC-based Paper by Chemical and Mechanical Treatments (III) - Handsheet physical properties -)

  • 이종훈;서영범;전양;이학래;신종호
    • 펄프종이기술
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    • 제32권2호
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    • pp.8-15
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    • 2000
  • This study is a continuation of the previous experimental analysis and is mostly focused on handsheet strength properties. Four completely different fibers, which were Hw-BKP, SW-BKP, White ledger, and OCC, were selected to investigate the effect of mechanical pre-treatment by Hobart mixer on handsheet strehgth properties. After equal time mechanical pre-treatment, the fibers were refined with laboratory valley beater for 10, 20 and 30 minutes, and handsheets were prepared from the fibers for physical strength comparison. Handsheets from SW-BKP and OCC showed 5-30% increase of breaking length, burst index, tear index, and compression index while handsheets from HW-BKP and White ledger no increase except tear index. In Hobart mixer pre-treatment, HW-BKP and White ledger fibers were easily attached to the wall of the mixer bowl and mechanical action was not effectively applied. The fiber length of Hw-BKP and White ledger were 0.837 mm and 1.591 mm, respectively, while SW-BKP and OCC were 2.744 mm and 2.033 mm, respectively, in weight weighted length. The effective mechanical pre-treatment seems to be related to the fiber length. Tear indexes of the pre-treated furnish were much higher than no pre-treatment at the same breaking length level.

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특허 지표 분석을 통한 국내 윤활유 제조 기술 평가 (The Evaluation of Korea's Competitiveness in Lubricants Industries Using Patent Index Analysis)

  • 김찬중;권성훈;김지용
    • Korean Chemical Engineering Research
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    • 제54권3호
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    • pp.332-339
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    • 2016
  • 본 연구에서는 윤활유 제조기술에 관한 국내외 특허 활동 분석을 통하여 윤활유 제조산업에서의 한국의 기술 경쟁력 분석 및 향후 대응 전략을 제시한다. 이를 위하여 본 연구에서는 한국을 비롯하여 미국, 일본 및 유럽연합 등 윤활유 제조산업에서의 주요 선진국들의 9가지 주요 윤활유 제조기술에 관한 최근 특허 동향을 통계적으로 분석한다. 또한 특허 수, 특허 인용수, 시장확보지수, 특허영향지수, 기술력지수 등 주요 특허 활동 평가 지표 분석을 통하여 한국의 윤활유 제조산업에서의 기술력, 경쟁력 등을 정량적으로 평가한다. 주요 결과로 한국은 뒤늦은 기술개발 등으로 윤활유 제조산업 진입은 상대적으로 늦으나 빠른 국내기술 확보를 통하여 높은 수준의 국내 기술을 보유하고 있다. 반면 상대적으로 낮은 국외 특허 활동으로 인하여 국내 기술의 국외 시장 진출이 용이치 않음을 분석하였다. 이 결과를 바탕으로 친환경 윤활유 시장 및 선진 기술 등 미래 유망 기술 전망 및 한국의 특허 전략을 제시한다.

Assessment of liquefaction potential of the Erzincan, Eastern Turkey

  • Duman, Esra Subasi;Ikizler, Sabriye Banu;Angin, Zekai;Demir, Gokhan
    • Geomechanics and Engineering
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    • 제7권6호
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    • pp.589-612
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    • 2014
  • This study includes determination of liquefaction potential in Erzincan city center. Erzincan Province is situated within first-degree earthquake zone on earthquake map of Turkey. In this context, the earthquake scenarios were produced using the empirical expressions. Liquefaction potential for different earthquake magnitudes (6.0, 6.5, 7.0) were determined. Liquefaction potential was investigated using Standard Penetration Test (SPT). Liquefaction potential analyses are determined in two steps: geotechnical investigations and calculations. In the first steps, boreholes were drilled to obtain disturbed and undisturbed soil samples and SPT values were obtained. Laboratory tests were made to identify geotechnical properties of soil samples. In the second step, liquefaction potential analyses were examined using two methods, namely Seed and Idriss (1971), Iwasaki et al. (1981). The liquefaction potential broadly classified into three categories, namely non-liquefiable, marginally liquefiable and liquefiable regions. Additionally, the liquefaction potential index classified into four categories, namely non-liquefiable, low, high and very high liquefiable regions. In order to liquefaction analysis complete within a short time, MATLAB program were prepared. Following the analyses, liquefaction potential index is investigated by Iwasaki et al. (1982) methods. At the final stage of this study, liquefaction potential maps and liquefaction potential index maps of the all study area by using IDW (inverse distance weighted) interpolation method in Geostatistical Analyst Module of ArcGIS 10.0 Software were prepared for different earthquake magnitudes and different depths. The results of soil liquefaction potential were evaluated in ArcGIS to map the distributions of drillings with liquefaction potential. The maps showed that there is a spatial variability in the results obtained which made it difficult to clearly separate between regional areas of high or low potential to liquefy. However, this study indicates that the presence of ground water and sandy-silty soils increases the liquefaction potential with the seismic features of the region.

국내 제조업에 대한 비가격 신재생에너지의 암묵가격, 대체가능성, 생산성 파급효과 분석 (An Analysis on Shadow Price, Substitutability, and Productivity Growth Effect of Non-Priced Renewable Energy in the Korean Manufacturing Industries)

  • 이명헌
    • 자원ㆍ환경경제연구
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    • 제24권4호
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    • pp.727-745
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    • 2015
  • 본 논문에서는 국내 제조업을 대상으로 통합개념의 '비가격'의 신재생에너지 투입에 대한 기업의 최적화 행태를 분석하기 위하여 투입요소의 가격에 대한 정보없이 추정이 가능한 투입물거리함수를 추정한다. 신재생에너지의 연도별 암묵 (shadow) 가격을 도출하여 변화 패턴을 근거로 향후 신재생에너지의 잠재가격을 예측한다. 신재생에너지와 화석에너지 간 대체 가능성에 대한 측정 등 잠재 생산성에 영향을 줄 수 있는 제반 환경을 평가하고, 기술변화와 기술 효율성 변화의 Malmquist 생산성 지수를 계측하여 신재생에너지 투입의 생산성 지수에 대한 파급효과 여부 및 크기를 분석한다. 분석 결과, 1992-2012년 기간 동안 신재생에너지의 암묵가격은 매년 평균 17%씩 증가하는 것으로 나타났으며, 신재생에너지와 비재생에너지는 대체가능성이 상호 낮은 것으로 측정되었다. 신재생에너지 투입량을 1% 증가시키면 산업 생산성은 연평균 약 0.04% 감소하는 것으로 나타났다.

골판지 고지의 물리화학적 처리에 의한 강도향상 (제3보 - 수초지의 물리적특성변화) (Strength property improvement of OCC-based paper by chemical and mechanical treatments (3 - handsheet physical properties))

  • 이종훈;서영범;전양;이학래;신종호
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2000년도 춘계학술발표논문집
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    • pp.70-70
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    • 2000
  • This study is a continuation of the previous experimental analysis and is mostly focused on handsheet strength properties. Four completely different fibers, which were Hw-BKP, Sw-BKP, white ledger, and OCC, were selected to investigate the effect of mechanical pre-treatment by Hobart mixer on handsheet strength properties. After equal time mechanical pre-treatment, the fibers were refined with laboratory valley beater for 10, 20 and 30 minutes, and handsheets were prepared from the fibers for physical strength comparison. Handsheets from SW-BKP and OCC showed 5-30% increase of breaking length, burst index, tear index, and compression index while handsheets from HW-BKP and white ledger no Increase except tear index. In Hobart mixer pre-treatment, HW-BKP and white ledger fibers were easily attached to the wall of the mixer bowl and mechanical action was not effectively applied. The fiber length of Hw-BKP and white ledger were 0.837mm and 1.591 mm, respectively, while SW-BKP and OCC were 2.744 mn and 2.033 mm, respectively, in weight weighted length. The effective mechanical pre-treatment seems to be related to the fiber length. Tear indexes of the pre-treated furnish were much higher than no pre-treatment at the same breaking length level.

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고점도 펄프를 위한 새로운 한지 펄프화법의 개발(제1보) - 닥나무 백피의 상압 펄프화 특성 - (Development of High Viscosity Pulping Method for Korean Paper (I) - Atmospheric Pressure Pulping Characteristics of Paper Mulberry White Bast -)

  • 이상현;최태호
    • 펄프종이기술
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    • 제43권2호
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    • pp.57-65
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    • 2011
  • Pulping of paper mulberry (Broussonetia kazinoki) white bast has been examined by novel atmospheric pressure pulping methods. The viscosity of pulp has been found to be highly sensitive and variable with pulping methods. Therefore, selections of pulping chemicals and conditions are very important. Two kinds of pulping procedures were employed for the high viscosity pulp manufacturing. The one is ammonium oxalate treatment and the other is sodium chlorite and acetic acid treatment. Not only chemical components and pulp yields which of paper mulberry white bast but also water retention value (WRV), whiteness index, yellowness index, and colors of every pulp were examined. The hot water, 1% NaOH, and ethanol-benzene extractives which of paper mulberry white bast were 4.48%, 28.45%, and 2.84%, respectively. The contents of holocellulose, lignin, and ash were 90.66%, 1.05%, and 2.18%, respectively. In the pulp yields, group 1 which treated with only ammonium oxalate were 77.04-81.71%, group 2 which treated with ammonium oxalate and acidified sodium chlorite separately and washed between first and second stages were 64.15-83.90%, group 3 which treated with ammonium oxalate and acidified sodium chlorite separately and not washed between first and second stages were 57.35-73.17%, and group 4 which treated with mixed ammonium oxalate and acidified sodium chlorite were 66.58-68.43%. The pulps treated with acidified sodium chlorite showed high whiteness index, but the pulps treated with only ammonium oxalate showed high yellowness index. Variations in the combinations of treatments resulted in different pulp characteristics.

CEN/TS 45545 출범에 따른 철도차량 화재안전 기술 동향에 대한 연구 (A Study on Technical Trend of Fire Safety on Railway Vehicles for Launch CEN/TS 45545)

  • 성시영;우이완;박재홍
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2010년도 춘계학술대회 논문집
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    • pp.1768-1773
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    • 2010
  • CEN/TS 45545 is Europe consolidation standard for fire safety on railway behicles. This is based on the International Union of Railways(UIC) and different European countries. It is intended to protect passengers and staff in railway in the event of a fire on board. It will be prepared in 2012. Based on this consolidate standard, they are going to make single market, for raising technical competitiveness, technical innovation and globalization of that standard. For this reason, European academies, manufacturers, and sub-manufacturers confer and stady animated about CEN/TS 45545. In Korea, get out the safety assessment for ues incombustible interior material, the needs of quantitative analysis on fire protection, demand on recognition of fire protection scenario, and define about fire load analysis are becomin more and more important. Therefore, this paper will estimate and compare Flammability, Smoke Density, Toxicity Index( this is the key point for appraised fire safety performance of material) between CEN/TS45545 and fire standards on railway vehicle. Then suggest criteria for fire safety on railway vehicles.

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