• 제목/요약/키워드: mixed

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철도노반 혼합(흙과 암)성토의 다짐특성에 관한 연구 (Study on compaction characteristics of mixed fill materials(rock and soil) in railway roadbed)

  • 김대상;박성용;송종우;김수일
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 추계학술대회 논문집
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    • pp.505-510
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    • 2007
  • Concrete track will be constructed in Gyungbu High Speed Railway II(GHSR II) stage construction site from Daegu to Busan. Concrete track is supported by substructure consisting of the original ground and embankment and does not allow the settlement of track because of its structural type. The embankment is composed of rock and soil mixture and settlement is feasible. So management of settlement of embankment is key point in successful construction of the concrete track. Compaction management of mixed fill materials is important in minimizing the settlement of embankment. In this study, in order to assess the compaction characteristics of mixed fill materials, large laboratory compaction tests were conducted. Mixed fill materials were obtained from two construction sites in GHSR II construction site. Modeled mixed fill materials having different rock type, fine content, maximum particle diameter, and moisture contents were prepared. From the test results, compaction characteristics of mixed fill materials were analysed.

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냉간압축하에서 혼합금속분말의 치밀화 모델 (A Densification Model for Mixed Metal Powder under Cold Coompaction)

  • 조진호
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2000년도 춘계학술대회논문집
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    • pp.112-118
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    • 2000
  • Densification behavior of mixed copper and tool steel powder under cold compaction was investigated. By mixing the yield functions proposed by Fleck et al. and by Gurson for pure powder in terms of volume fractions and contact numbers of Cu powder new mixed yield functions were employed for densification of powder composites under cold compaction. The constitutive equations were implemented into a finite element program (ABAQUS) to compare with experimental data for densificatiojn of mixed powder under cold isostatic pressing and cold die compaction. finite element calculations by using the yield functions mixed by contact numbers of Cu powder agreed better with experimental data than those by volume fractions of Cu powder.

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초고층 주상복합 건물 거주자의 지역공동체의식과 근린활동 - 거주자와 입주예정자의 비교를 중심으로 - (Sense of Community and Community Interaction of Mixed-use Residential Buildings′ Residents : Comparisons between Groups of Mixed-use Residential Buildings′ Residents and their Expected Residents)

  • 이경희;채혜원
    • 가정과삶의질연구
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    • 제22권3호
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    • pp.1-9
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    • 2004
  • The purposes of this study were (a) to compare the level of sense of community and community activity of the mixed-use residential buildings' residents with the expected residents for the mixed-use residential building, (b) and to investigate the degree of their needs of social interaction. For the survey the questionnaire from 176 residents of mixes-use residential building in Seoul, and 67 expected residents in Bundang Newtown are used. The analytical methods adopted in this study were frequency, percentage, chi-square test and t-test. It was found that the level of sense of community and the community activities of the mixed-use residential building' residents were higher than those of the expected residents. Their residents reported higher degree of participation on community activities than the expected residents. It was also found that the common space in their residential area promoted the residents' sense of community and community activity.

냉간압축하에서 혼합 금속분말의 치밀화 거동에 관한 유한요소해석 (A Finite Element Analysis for Densification Behavior of Mixed Metal Powder under Cold Compaction)

  • 조장혁;조진호;김기태
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집A
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    • pp.393-398
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    • 2000
  • Densification behavior of mixed copper and tool steel powder under cold compaction was investigated. By mixing the yield functions originally proposed by Fleck-Gurson for pure powder, a new mixed yield functions In terms of volume fractions and contact numbers of Cu powder were employed in the constitutive models. The constitutive equations were implemented into a finite element program (ABAQUS) to compare with experimental data. and with calculated results from the model of Kim et at. for densification of mixed powder under cold isostatic pressing and cold die compaction. Finite element calculations by using the yield functions mixed by contact numbers of Cu powder agreed better with experimental data than those by volume fractions of Cu powder.

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단일 및 혼합모드하에서 304스테인리스강의 피로균열 진전속도와 방향특성 (Fatigue Crack Growth Rates and Directions in STS304 under Mode I and Mixed Mode)

  • 권종완;양현태
    • 한국공작기계학회논문집
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    • 제11권3호
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    • pp.102-109
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    • 2002
  • The fatigue crack growth under mixed mode condition has been discussed within the scope of linear fracture mechanics such as maximum tangential stress, maximum tangential principal stress and minimum strain energy density. The purpose of this study is to investigate the characteristics of fatigue test crack growth in 304 stainless steel under mixed node. The fatigue test results carried out by using inclined pre-crack specimens was compared to both of the theoretical predictions of the criteria, maximum tangential stress and stain energy density. As difference from theoretical analysis, the transition region from mixed mode to mode I appeared in the fatigue test. There is deep relationship between the angle of slanted pre-crack and transition. Therefore, as applying the different stress intensity factor to each node I+II and mode I, the directions and rates of fatigue crack growth are evaluated more accurately under mixed mode.

Hydrox Gas 혼합연소특성 에 관한 연구 (A Study on the Characteristics of Mixed Combustion for Hydrox Gas)

  • 김홍건;곽이구
    • 한국생산제조학회지
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    • 제19권2호
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    • pp.230-234
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    • 2010
  • Hydrox gas which is the mixed gas of hydrogen and oxygen gained fromwater electrolysis is one of the new clean energy sources and thus is researched and commercialized actively. Especially, it can be replaced the fossil energy and shows the better quality compared to the conventional energy such as LPG or acetylene gas. The mixed gas of hydrogen and oxygen is gained from water electrolysis reaction. It has constant volume ratio 2:1 of hydrogen and oxygen, and it is used as a source of thermal energy by combustion reaction. Further, hydrox gas is nearly a mixed ideal gas combusting itself completely and its combustion shows anunique characteristics of implosion. In this study, temperature rise effects on hydrox gas content through mixed combustion test of kerosene and hydrox gas and LPG and hydrox gas are investigated. it is also confirmed that economy of mixed combustion of hydrox gas as effective energy is fairly probable.

혼합모드(I+II)에서 피로균열진전에 미치는 응력비의 영향 (Effect of Stress Ratio on Fatigue Crack Growth in Mixed Mode(I+II))

  • 공병채;최명수;권현규;최성대
    • 한국기계가공학회지
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    • 제8권4호
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    • pp.90-96
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    • 2009
  • The loading condition of actual construction works is complex. The shear effect of mixed-mode load component are crack propagation mechanism in step larger than the crack initial mechanism. Therefore, in this study received a mixed-mode loading on fatigue crack stress ratio on crack propagation path and speed of progress to learn whether stress affects crack propagation. ${\Delta}$ P a constant state of fatigue tests in Mode I, II give the same stress ratio, frequency 10Hz, sinusoidal waveform was used. A lower stress ratio fatigue crack propagation angle is small. This is less affected by the Mode II. Therefore, a mixed-mode fatigue crack propagation is to progress by the Mode. Stress ratio in a mixed mode crack in the path of progress and found a lot of impact.

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Gumbel Mixed 모형을 이용한 용담댐 유역의 강수량 빈도 해석 (Precipitation Frequency Analysis Using Gumbel Mixed Model in the Yongdam Dam Basin)

  • 이길성;선우우연
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2011년도 학술발표회
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    • pp.378-382
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    • 2011
  • 지난 2010년 9월 21일~22일 서울지역에 발생한 시간당 최고 250 mm의 집중호우는 짧은 지속 시간동안 강수총량이 컸기 때문에 재산 및 인명피해가 상당했다. 기존의 강우빈도해석은 각 사상의 강수총량 또는 지속시간별 연최대치강우량을 기준으로 산정하는 방식인데 이번 이상홍수의 경우에는 강수총량과 첨두강수량이 높음에도 불구하고 지속시간이 짧기 때문에 체감적 강도에 미치지 못하는 재현기간을 가질 것으로 생각된다. 그러므로 빈도해석 시 기존 일변량 빈도해석과 달리 이변량, 삼변량, 다변량의 빈도해석이 필요할 것으로 사료된다. 본 연구의 대상유역은 용담댐 유역으로 강수총량, 지속시간, 첨두값을 대상으로 상관관계를 비교하여 지속시간과 첨두강수량에 대한 Gumbel mixed 모형을 적용하여 그에 따른 재현기간을 산정하였다. 또한 단일 Gumbel 모형과의 비교를 통해 두 모형의 차이점을 밝힘으로써 Gumbel Mixed 모형에 대한 신뢰도를 높였다. 따라서 본 연구에서 제안한 Gumbel mixed 모형은 이상홍수 뿐 아니라 다양한 수문학적 설계와 관리에 유용할 것으로 기대된다.

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혼류생산 방식을 적용한 신개념 용접조립 기술 연구 (Experimental Study of New Welding Assembly Technology Applied with Mixed-Model Production Method)

  • 박동환;구자준
    • 한국생산제조학회지
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    • 제23권6호
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    • pp.602-608
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    • 2014
  • Mixed-model production lines are often used in manufacturing systems. In production lines, different product types are simultaneously manufactured by processing small batches. This paper describes a new welding assembly technology involving the development of experimental models for a mixed-model production line in an automobile company. Due to the extensive number of models, the design of a welding assembly system is complicated. Performance evaluation is an important phase in the design of welding assembly lines in a mixed-model production environment. In this study, a new welding assembly technology for a mixed-model production method was used to weld the package tray and dash panel of a vehicle.

인공토양을 이용한 옥수수와 콩의 생육 연구 (Study on the Grow of Corn and Soybean in Artificial Soil)

  • 김선주
    • 한국농공학회지
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    • 제42권5호
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    • pp.59-69
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    • 2000
  • Sludge is generated in the process of water and wastewater treatment, and it has been causing various environmental problems. From this point of view, recycling of sludge appears to be the best way. The firing technology in pottery industry is applied to the sludge treatment , and the final product is called artificial soil. The effect of mixed artificial soil with upland soil was investigated through the crop growth experiment and the physical & chemical characteristics of the mixed soils were analyses. After the growth experiment , mixed soil plots contained more CEC, OM, TN, TP than upland soil plots. This result shows that the artificial soil produced form sludge can be mixed with upland soil, and crop can be increased. From the growth analysis, growth of soybean and corn in the mixed soil plots was better than that in the original upland soil plots. Heavy metals contents in the mixed soil plots were within the quality standard. This is a promising result since in most cases heavy metals are the most concern in the application of sludge product to farmland.

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