• 제목/요약/키워드: rate of length change

검색결과 458건 처리시간 0.033초

Y-Jet 노즐에서의 혼합관 길이변화에 따른 분무특성 연구 (Change of Spray Characteristics with Mixing Port Length of Y-Jet Atomizers)

  • 송시홍;이상용
    • 대한기계학회논문집
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    • 제18권11호
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    • pp.3021-3031
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    • 1994
  • Experiments have been performed to find out the effect of the mixing port length of Y-jet atomizers on the spray performance, using air and water as the test fluids. Water and air flow rates and drop sizes were measured at each injection pressure condition for different mixing port length. The air flow rate was almost unaffected by the change of the mixing port length. However, the water flow rate was relatively susceptible to the change of the mixing port length. The mixing point pressure was very much influenced by the mixing port length. Variations of spatial distribution of Sauter Mean Diameter (SMD, $D_{32}$) and the cross-section-averaged SMD ($D_{32,m}$) with different mixing port length and air/water mass flow rate ratio were examined. Generally, when the mixing port length was reduced, the mean drop size decreased and became spatially even.

지하수 양수량에 따른 지하수유동 및 포획구간 특성 변화 (Characteristics of Ground Water Capture Zone according to Pumping Rate)

  • 안승섭;박동일;오영훈
    • 한국환경과학회지
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    • 제22권7호
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    • pp.895-903
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    • 2013
  • This study analyzed on characteristics of the ground-water capture zone in coastal areas and mid-mountainous area according to pumping rate. For this study, it targeted Jejudo island where is the volcanic island. To analyze, MODFLOW model and MODPATH model, which are the ground-water flow analysis models, were used. As a result of research, the following conclusions could be obtained. As a result of analyzing influence of a change in pumping time upon length of capture zone, the length of capture zone in coastal area was indicated to be greater in the changing ratio compared to the length of capture zone in mid-mountainous area. Next, in the coastal area, the pumping rate and the capture-zone length are changing similarly. However, in mid-mountainous area, the length of capture zone was indicated to grow when the pumping rate comes to exceed 1,500m3/day. As a result of analyzing influence of a change in pumping time upon capture area, the tendency of a change in the area was indicated similarly in coastal areas and mid-mountainous area. Especially, it could be known that the larger pumping rate leads to the more definite increase in tendency to a change in capture area. Based on this study, it was allowed to be possibly used in the suitable pumping rate in coastal areas and mid-mountainous area of the volcano island in the future. A follow-up research is judged to necessarily analyze the influence of tubular-well group upon capture zone by additionally analyzing a change in capture zone targeting the concentrated tubular well.

프리믹스 시멘트 종류 및 CGS 치환에 따른 콘크리트의 길이변화율 특성 (Characteristics of Concrete Length Change Rate according to Premixed Cement Types and CGS replacement rate)

  • 한준희;김수호;백성진;한수환;김종;한민철
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2022년도 봄 학술논문 발표대회
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    • pp.154-155
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    • 2022
  • In this study, propose a plan to efficiently utilize CGS, a by-product generated from IGCC, as a mixed fine aggregate for concrete. The effect of the premixed cement types and CGS replacement rate on the overall characteristics and length change rate of concrete was analyzed. As a result of the analysis, the effect of CGS was found to be insignificant, and the effect of cement was found to be dominant.

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ATM ABR 서비스에서 큐 길이 변화를 이용한 개선된 폭주 제어 알고리즘 (Advanced Congestion Control Algorithm Using Change of Queue Length in ATM ABR Service)

  • 김체훤;강현철;곽지영;남지승
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 하계종합학술대회 논문집(3)
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    • pp.109-112
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    • 2000
  • The EPRCA(Enhanced Proportional Rate Control Algorithm) is one of the explicit rate control algorithm recommended by the ATM forum. EPRCA algorithm is using only two threshold to buffer change is not considered for calculating ER value. In this paper to cover the shortage, two more variables are added for considering increase of buffer quantity. So calculating proper ER would avoid before getting into the congestion situation. To analysis the affect, EPRCA and proposed algorithm are compared through simulation by analysis of change of buffer length and ACR change

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하복의 체표변화에 따른 동작적합성에 관한 연구 -하복동작 및 체형을 중심으로- (A Study on the Movement-Fitness according to the Surface changing of Lower-Limb -On the Movements and Shapes of Lower-limb-)

  • 박영득;서영숙
    • 한국의류학회지
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    • 제20권2호
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    • pp.257-269
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    • 1996
  • The puropose of this study was to investigate the movement-fitness according to the surface changing of lower limb The experimental items were divided into the lower limb movements (5) and body-shapes (7). This study was done by the expansion and contraction rate consideration of length, girth Also, the lower half of body shape-change on the movements and body-shapes by flat shell was done simultaneously. The summarized findings resulted from experiments and investigation are suggested as follows; First, when commpared the expansion and contraction rate of the length and girth items, the expansion rate of the back crotch length (14~20%), hip girth (10~ 21%) and knee girth (6.2~18.5%) in rabbit leap movement was the most notable among all variables considered in this experimentation. On the others hand, the front croth length (-22~-52%) contracted remarkably. And big-thigh type was the most notable on the body-shape comparision. Second, in comparision of the expansion and contraction rate of the area on the blocks, the expansion of the hip (50~200%) and knee (51~74%) block was the most remarkable. Especially, in the sit on knees movement of the hip-down type expanded 209.4%. Third, in comparision of the lower half of body shape-change, on the movements and body- shapes by the flat shell, under the influence of knee-joint and hip-joint the shape-changs of the hip and knee block was the most notable. But the shape-change of the waist, abdomen, calf, and ankle was feeble.

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Development of decontamination equipment to remove hot particulates contaminated in hot cell at KAERI

  • Kim Gye-Nam;Narayan M.;Won Hui-Jun;Jung Chong-Hun;Oh Won-Zin;Park Jin-Ho
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
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    • pp.258-268
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    • 2005
  • A new approach has been adopted to remove the hot particulates from nuclear facilities, KAERI, South Korea, by using the new compact cyclone train, made of steel ness steel, with optional vortex finder length. Flow rate results showed a dramatic change in removal efficiency, performance was changed with the change of exit tube length. The 15 m/s flow rate was found suitable one for new equipment with the 49 mm optimum exit tube length for 76 mm cyclone body diameter. Results shows the removal efficiency for $1\;{\mu}m$ was more than $65\%$ and for $10\;{\mu}m$ was seen ${\~}97\%$. Over 15 m/s flow rate, was not shown much different in removal efficiency. The removal efficiency increased with the flow rate, and pressure drop. Cut size diameter decrease with the inlet flow rate. Cut size diameter found lowest with 49 mm exit tube length and 15 m/s flow rate. For filters the performance decreased with the inlet velocity increased.

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알칼리 자극제 혼입 고로슬래그 콘크리트의 건조수축과 공극구조 (Drying shrinkage and Pore Structure of Blast Furnace Slag Concrete Mixed Alkaline Stimulation)

  • 박지웅;이건철;고산
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 추계 학술논문 발표대회
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    • pp.32-33
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    • 2016
  • This purpose of this study is to find the properties of pore structure and length change of blast furnace slag cement added alkali powder stimulant on shrinkage reducing agent presence. In length change, the specimen added alkaline stimulant was smaller than normal blast furnace slag concrete. And the specimen added shrinkage reduction agent was confirmed to show smaller rate of length change than the length. In MIP analysis of 1day-age, 0.1㎛ subsequent pore amount of the specimen added alkaline stimulant was significantly smaller value the normal blast furnace slag concrete specimen.

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BS 치환 모르타르의 ERCO 도포시 수분증발 및 수축변화에 미치는 영향 (Impact of BS replacement mortar's application to ERCO on moisture evaporation and contraction changes)

  • 백철;이제현;황찬우;장덕배;한민철;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 추계 학술논문 발표대회
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    • pp.115-116
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    • 2016
  • This study applied BS replacement mortar's ERCO to see what impact it has on moisture evaporation and contraction changes, and resulted in the following. Depending on the rate of change in length according to the cure method of BS replacement mortar, high-strength areas were shown to have a bigger increase in the rate of change in length than regular or low-strength areas, and differences in rate of change in length due to ERCO cure methods were shown to be slight. For rate of changes in mass, on the whole there was an increase in the order of dry curing, cover curing, 7-day water curing, and28-day water curing. A comprehensive view says that after removal of test piece specimens, ERCO application did not expect a sufficient curing effect in the BS area.

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고온을 받은 석회암 골재의 습도경시변화에 따른 체적거동 (Volume Change Caused from the Moisture Change in the Limestone Material Pressured under High Temperature)

  • 풍해동;손호정;허영선;한민철;양성환;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2011년도 추계 학술논문 발표대회
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    • pp.111-113
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    • 2011
  • This study investigated about how much the limestone's volume was changed as time passed while maintaining a certain level of moisture condition in the limestone material for concrete under high temperature. The result is summarized as follows: It was appeared that the limestone material under high temperature emitted some CO2 resulting from the decarboxylation, so that as the heating temperature was increased, the limestone's length change rate was decreased. In the leave time change after heating the stone, the both conditions of 50% and 100% made the limestone create Ca(OH)2 using some H2O. So it was appeared that as time passed, the limestone's length change rate first increased because of its volume expansion, but the rate was reduced after the limestone material was crumbled.

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유영운동에 의한 잉어의 심박수변화 (Heart Rate Change of Carp Cyprinus Carpio During Swimming Activity)

  • 안영일
    • 수산해양기술연구
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    • 제31권1호
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    • pp.24-28
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    • 1995
  • Exercise physiology of fish was studied by means of Electro-cardio-gram(ECG) technique with wired electrode system. Effects of swimming activity on the heart rate change for carp Cyprinus carpio was observed and analysed under swimming speeds among 1~3 Body Length/s and swimming durations of 10 and 60 minutes in the flume tank. The heart rate increase during swimming activity was observed in higher speed and longer duration conditions. The exercise effect on the heart rate continued even after fish stopped swimming. The time for recovery after exercise was tended to be elongated with the higher exercise condition.

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