• Title/Summary/Keyword: filling

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Studies on the Duration and Rate of Grain Filling in Rice (Oryza sativa L.) I. Varietal Difference and Effects of Nitrogen (수도의 등숙기간 및 등숙속도 연구 I. 품종간 차이 및 질소의 영향)

  • 조동삼;정승근;박연규;손석용
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.32 no.1
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    • pp.103-111
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    • 1987
  • Understanding grain filling characteristics represented by grain filling duration and grain filling rate is import-ant in improving higher yielding varieties and developing better cultural methods of rice (Oryza sativa L.). Recently developed 6 Japonica and 6 Japonica/Indica varieties were grown under 3 nitrogen levels at Experimental Farm of Chungbuk National University in 1986. The range of grain filling duration of 12 varieties was 20.9-39.0 days, while grain filling rate ranged from 53.8 to 136.6 mg. panicle$^{-1}$. day$^{-1}$. Although the difference of the average grain filling duration between Japonica varieties and Japonica/Indica was less than 4 days, the average grain filling rate of Japonica/lndica varieties was greater than Japonica more than 30%. Samgangbyeo showed the shortest grain filling duration of 21.0-24.2 days and the greatest grain filling rate of 119.3-143.8 mgㆍpanicle$^{-1}$. day$^{-1}$ under 3 nitrogen levels, while Seomjinbyeo and Milyang 23 showed the quite opposite grain filling characteristics. Nitrogen levels did not show any significant effects on grain filling characteristics. Negative correlation was round between grain filling duration and grain filling rate, and significant positive correlations of grain filling rate with grains/panicle, grain weight and panicle weight indicated that grain filling rate is more important characteristics of grain filling. Pathway analysis revealed that contribution of grain filling rate to panicle weight is rather indirect through grain weight.

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Association of Duration and Rate of Grain Filling with Grain Yield in Temperate Japonica Rice (Oryza sativa L.)

  • Yang, Woon-Ho;Park, Tae-Shik;Kwak, Kang-Su;Choi, Kyung-Jin;Oh, Min-Hyuk
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.52 no.1
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    • pp.112-121
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    • 2007
  • Grain filling is a crucial factor that determines grain yield in crops since it is the final process directly associated with crops' yield performance. Grain filling process can be characterized by the interaction of rate and duration of grain filling. This study was conducted, using 16 temperate japonica rice genotypes, with aims to (1) seek variations in grain filling duration and rate on area basis, (2) compare the contribution of grain filling duration and rate to grain yield, and (3) examine the influence of temperature and solar radiation for effective grain filling on grain yield in relation to grain filling duration and rate. Grain filling rate and duration exhibited highly significant variations in the ranges of $20.7{\sim}46.3\;g\;m^{-2}d^{-1}\;and\;11.2{\sim}35.5$ days, respectively, depending on rice genotypes. Grain yield on unit area basis was associated positively with grain filling duration but negatively with grain filling rate. Grain filling rate and duration were negatively correlated with each other. Final grain weight increased linearly with the rise in both cumulative mean temperature and cumulative solar radiation for effective grain filling. Higher cumulative mean temperature and cumulative solar radiation for effective grain filling were the results of longer grain filling duration, but not necessarily higher daily mean temperature and daily solar radiation for effective grain filling. Grain filling rate demonstrated an increasing tendency with the rise in daily mean temperature for effective grain filling but their relationship was not obviously clear. It was concluded that grain filling duration, which influenced cumulative mean temperature and cumulative solar radiation for effective grain filling, was the main factor that determined grain yield on unit area basis in temperate Japonica rice.

The Filling Imbalance in Multi-Cavity Injection Molds with Unary Branch Type Runner Lay-out (편측 분기형 러너 배열을 가진 다수 캐비티 사출금형에서의 충전 불균형도)

  • 강철민;정영득
    • Transactions of Materials Processing
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    • v.13 no.7
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    • pp.580-585
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    • 2004
  • Almost all injection molds have multi-cavity runner system fur productivity and are designed with geometrically balanced runner system in order to minimize filling imbalance between cavity to cavity during processing. However, filling imbalances have been observed though geometrically balanced runner lay-out. Generally, these filling imbalances are due to thermal unbalance, viscosity, characteristic of polymers and so on. These kinds of filling imbalances have already been reported by Beaumont since 1997, but his research has mainly focused on filling imbalance at binary runner. In this study, we conducted an experimental study about the filling imbalances in unary branch runner as well as binary branch runner and inquired into the causes of filling imbalances. The results could be summarized as fellowing: Filling imbalances existed in multi-cavity mold with unary branch runner, it could be decreased by optimizing processing condition such as increasing injection rate, and it is almost proportion to each polymer's temperature sensibility.

A Study of a Simultaneous Filling and Solidification During Casting Process (충전과 상변화 현상을 포함한 주조과정에 대한 연구)

  • Im, lk-Tae;Kim, Woo-Seung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.8
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    • pp.987-996
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    • 1999
  • An algorithm for modeling the filling of metal into a mold and solidification has been developed. This algorithm uses the implicit VOF method for a filling and a general implicit source-based method for solidification. The model for simultaneous filling and solidification is applied to the two-dimensional filling and solidification of a square cavity. The effects of the wall temperature and gate position on the solidification are examined. The mixed natural convection flow and residual flow resulting from the completion of a filling are included in this study to investigate the coupled effects of the filling and natural convection on solidification. Two different filling configurations (assisting flow and opposite flow due to the gate position) are analysed to study the effects of residual flow on solidification. The results clearly show the necessity to carry out a coupled filling and solidification analysis including the effect of natural convection.

Cu Filling Characteristics of Trench Vias with Variations of Electrodeposition Parameters (Electrodeposition 변수에 따른 Trench Via의 Cu Filling 특성)

  • Lee, Kwang-Yong;Oh, Teck-Su;Oh, Tae-Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.13 no.4
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    • pp.57-63
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    • 2006
  • For chip-stack package applications, Cu filling characteristics into trench vias of $75{\sim}10\;{\mu}m$ width and 3 mm length were investigated with variations of electroplating current density and current mode. At $1.25mA/cm^{2}$ of DC mode, Cu filling ratio higher than 95% was obtained for trench vias of $75{\sim}35{\mu}m$ width. When electroplated at DC $2.5mA/cm^{2}$, Cu filling ratios became inferior to those processed at DC $1.25mA/cm^{2}$. Pulse current mode exhibited Cu filling characteristics superior to DC current mode.

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Changes in soil physical properties of coir dust-mixed substrate as influenced by various filling amounts (용기내 충전량 변화에 따른 코이어 더스트 혼합상토의 물리성 변화)

  • Choi, Jong Myung;Lee, Hee Su
    • Korean Journal of Agricultural Science
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    • v.40 no.3
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    • pp.203-208
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    • 2013
  • Differences in the filling amount of substrates in container can influence severely on the soil physical properties and crop growth. This research was conducted to secure the fundamental informations related to the changes in soil physical properties as influenced by the filling amount of coir dust-based substrates in container. For the experiment, three substrates were formulated by blending coir dust (CD) with expanded rice hull (CD+ERH, 8:2, v/v), carbonized rice hull (CD+CRH, 6:4, v/v) or ground and aged pine bark (CD+GAPB, 8:2, v/v). Based on the optimum bulk density, the amount of substrates filled in 347.5mL aluminum cylinder were adjusted to 90, 100, 110, 120, and 130%. Then the changes in total porosity (TP), container capacity (CC), and air-filled porosity (AFP) by various filling amounts were measured. The TP decreased linearly in CD+ERH and CD+GAPB and quadratically in CD+CRH as the filling amounts of the media increased from 90% to 130%. The CC in CD+ERH and CD+GAPB media increased as the filling amount increased from 90% to 120%, then decreased in 130%, showing quadratic change. The CC in CD+CRH was the highest in 90% filling amount and decreased gradually as the filling amount of root medea increased. The AFPs in CD+ERH and CD+GAPB media were 38 and 37%, respectively in 90% filling amount and they decreased drastically until 110% filling, then gradually in 120 and 130% filling amount showing the quadratic changes. The AFP of CD+CRH at 90% filling amount was 22% and it decreased as the filling amount increased until 130%, showing linear change. These results indicate that the increase in filling amount of substrates influenced more severely the AFP than CC, and careful consideration on container filling is required to provide a better root condition thus maximize crop growth.

Weavability Limit of Yarns with Thickness Variation in Shuttleless Weaving

  • Seyam, Abdelfattah M.
    • Fibers and Polymers
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    • v.4 no.4
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    • pp.176-181
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    • 2003
  • Theoretical weavability limit relationships of fabrics from regular warp yarns and fancy filling yams with thickness variation in shuttleless weaving are reviewed. The relationships correlate maximum warp and filling cover factors, warp and filling yarn characteristics, the distribution of thick and thin places of filling yarn over the fabric surface, and the warp and filling weave factor. The research considers single filling feeder and multiple feeders cases. Additionally, comparisons between the weavability limit of regular yarns and fancy yams in shuttle and shuttleless weaving are given.

On the new mold structure with multi-point gate for filling-balance mold (다점 핀포인트 금형에서 균형충전이 가능한 사출금형 구조)

  • Kwon, Youn-Suk;Jeong, Yeong-Deug
    • Design & Manufacturing
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    • v.2 no.5
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    • pp.25-29
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    • 2008
  • Almost all injection molds have multi-cavity runner system for mass production, which are designed with geometrically balanced runner system in order to accomplish filling balance between cavity to cavity during processing. However, even though geometrically balanced runner is used, filling imbalance have been observed. Filling imbalance could be decreased by modifying processing conditions such as injections rate, mold temperature, injection pressure, melt temperature that are related to shear, viscosity. In this study, a series of experiment was conducted to investigate filling imbalance variation when modifying runner layout and ploymer and to determine which processing condition influences as the primary cause of filling imbalance in geometrically balanced runner system. The filling imbalance was desreased up to result range of $3{\leq}DFI{\leq}8(%)$ by using a new runner system for balanced filling.

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A Study on the Filling Imbalances between Multi-Cavity in Hot-Runner Mold (핫러너 금형에서 다수 캐비티 사이에 발생하는 충전불균형에 관한 연구)

  • Han Seong Ryeol;Kang Chul Min;Han Kyu Taek;Jeong Yeong Deug
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.9 s.174
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    • pp.173-178
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    • 2005
  • Recently plastic parts are molded for the purpose of mass production in multi-cavity system. Therefore, designer is usually designing mold that has geometrically balanced runner lay-out for filling balance at each cavity. Although, mold is manufactured with geometrically balanced runner lay-out, there are actually filling imbalances in the cavities. These filling imbalances phenomenon are caused by complicated interaction between melt and mold. In this study, based on previous studies for filling imbalances in cold-runner mold, filling imbalances in hot-runner mold were investigated by CAE and injection molding experiments. ABS and PMMA as amorphous polymer, PA as crystalline polymer were used to compare the filling imbalances. There were different results of CAE and experiment. The filling imbalances decreased as injection rate increased without regard to kind of resins and were lower than the one of cold-runner.

A Study on the Filling Imbalances between Multi-Cavity in Hot-Runner Mold (핫러너 금형에서 캐비티사이의 충전불균형 현상에 관한 연구)

  • Han S.R.;Jeong Y.D.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.598-601
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    • 2005
  • Plastic parts are molded for the purpose of mass production in multi-cavity system. Therefore, designer is usually designing molds that has geometrically balanced runner lay-out for filling balance at each cavities. Although, mold is manufactured with geometrically balanced runner lay-out, there are actually filling imbalances in cavities. These filling imbalances phenomenon are caused by complicated interaction between melt and mold. In this study, based on previous studies for filling imbalances in cold-runner mold, filling imbalances in hot-runner mold were investigated by CAE and injection molding experiments. ABS, PMMA as amorphous polymer and PA, PP as crystalline polymer were used to compare the filling imbalances. The filling imbalances decreased as injection rate increased without regard to kind of resins and were lower than the one of cold-runner.

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