• 제목/요약/키워드: Homogenized

검색결과 403건 처리시간 0.021초

INCOMPRESSIBLE NAVIER-STOKES EQUATIONS IN HETEROGENEOUS MEDIA

  • Pak, Hee Chul
    • 충청수학회지
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    • 제19권4호
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    • pp.335-347
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    • 2006
  • The homogenization of non-stationary Navier-Stokes equations on anisotropic heterogeneous media is investigated. The effective coefficients of the homogenized equations are found. It is pointed out that the resulting homogenized limit systems are of the same form of non-stationary Navier-Stokes equations with suitable coefficients. Also, steady Stokes equations as cell problems are identified. A compactness theorem is proved in order to deal with time dependent homogenization problems.

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Al-Mg-Mn합금의 기계적(機械的) 성질(性質)에 미친 여비압재(予備圧在)의 영향(影響) (Effect of Pre-Rolling on the Mechanical Properties of AI-Mg-Mn Alloy)

  • 예길촌;맹선재
    • Applied Microscopy
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    • 제4권1호
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    • pp.5-10
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    • 1974
  • 본 실험에서는 여비압연이 4. 6%Mg-0.5% Mn-0.18%Cr의 알루미늄합금의 균질화처리 및 그의 기계적 성질에 마치는 영향을 조사하였다. 여비압연후 균질화 열처리된 시편은 주조상태의 시편에 비하여 실온 인장강도 및 연신률이 증가되고 있음을 보여주었다. $400^{\circ}C$의 고온 인장시험의 결과는 여비압연후 균질화열처리한 시편이 주조상태 또는 그의 균질화처리만 시행한 것에 비하여 다소 낮은 인장강도와 현저히 향상된 연신률을 소지함을 보여주었다. 여비압연후 균질화열처리된 시편의 금속현미경조직은 다른 시편들에 비해 결정입계에 ${\beta}$ 상등의 제2상이 현저히 감소되고 있음을 나타내고 있다. 시편의 결정입내 및 입계에 있어서의 주된 합금첨가원소인 Mg 분포상태를 EPMA를 사용하여 조사하였다. 이 결과는 균질화처리를 시행하기 전에 여비압연을 도입함으로써 균질화처리의 효과가 증대되고 있음을 보여주고 있다.

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Cholesterol Removal from Homogenized Milk with Crosslinked β-cyclodextrin by Adipic Acid

  • Han, Eun-Mi;Kim, Song-Hee;Ahn, Joungjwa;Kwak, Hae-Soo
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권12호
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    • pp.1794-1799
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    • 2005
  • The present study was carried out to develop crosslinking of $\beta$-cyclodextrin ($\beta$-CD) using adipic acid, and to determine the optimum conditions of different factors ($\beta$-CD concentration, mixing temperature, mixing time and mixing speed) on cholesterol reduction from homogenized milk. Crosslinked $\beta$-CD was prepared with adipic acid. When the milk was treated with different conditions, the cholesterol removal rate was in the range of 92.1 to 93.1% with 1% $\beta$-CD addition, which were not significantly different among treatments. After cholesterol removal from milk, the used crosslinked $\beta$-CD was washed for cholesterol dissociation and reused. For recycling study, the cholesterol removal rate in the first trial was 92.5%, which was mostly same as that using new crosslinked $\beta$-CD. With repeated ten time trials using same sample, 81.4% of cholesterol was removed from milk. Therefore, the present study indicated that the optimum conditions for cholesterol removal using crosslinked $\beta$-CD were 1% $\beta$-CD addition and 10 min mixing with 400 rpm speed at 5$^{\circ}C$ with over 90% cholesterol removal. In addition, crosslinked $\beta$-CD made by adipic acid resulted in the effective recycling efficiency.

3차원 중성자 확산계산을 위한 KMRR Hafnium 조정집합체 균질화에 대한 연구 (Homogenization of KMRR Hafnium Control Assembly for 3-D Diffusion Calculation)

  • Park, Hang-Bok;Kim, Young-Jin;Kim, Hark-Rho;Lee, Ji-Bok
    • Nuclear Engineering and Technology
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    • 제20권4호
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    • pp.233-240
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    • 1988
  • KMRR은 잉여반응도 및 출력분포조절을 위하여 Hafnium관을 사용한다. 현재 노심해석은 핵연료집합체 단위로 균질화된 5군 군정수를 이용하여 중성자 확산코드인 VENTURE을 이용한다. Hafnium관내에 핵연료가 들어있는 특수한 조정 집합체에 대해서도 이러한 균질화된 군정수를 사용한 중성자 확산계산이 적용될 수 있는가를 조사하였다. 비교계산은 중성자 수송코드인 TWOTRAN을 사용하여 잉여반응도 및 출력 준위에 대해 수행하였다. 계산결과 현재의 균질화된 군정수를 사용하는 중성자 확산계산이 큰 오차없이 적용할 수 있는 것으로 나타났다.

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미역과 다시마를 주원료로 한 묵 제조1. 미역, 다시마묵의 최적 조건과 그 물성에 관하여 (Preparation of Mook with Sea Mustard and Sea Tangle 1. The Optimum Condition of Sea Mustard and Sea Tangle Mooks)

  • 정용현;김건배;최선남;강영주
    • 한국식품영양과학회지
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    • 제23권1호
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    • pp.156-163
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    • 1994
  • To investigate the optimum conditions of seaweed Mooks prepared with sea mustard (Indaria pinnatifida) and sea tangel(Laminaria japonica), pH, viscosity , yield and jelly strength were studied on the sol and /or gel (Mook ) made from homogenized seaweeds. Solubilization conditions of homogenized seaweeds were heating at $65^{\circ}C$ for one hour after mixing homogenized seaweed with 1 % $K_2$HPO$_4$ by 1 ; 1 (v/v) . Gelation conditions were 24 hrs by natural permeation of Ca++ into the sol in three times (v/v) of 1 % CaCl$_2$ solution to solubilized seaweed passed through 60 mesh of sieve. There are generally no relationship between viscosity of solubilized seaweed and jelly strength of Mook produced by gelation of the sol in CaCl$_2$ solution . Jelly strength of sea mustard Mook was more than 500g/$\textrm{cm}^2$ , yield was 87.5% of the solubilized and filtrated seaweed . Jelly strength and specific gravity of sea tangle Mook were higher those of sea mustard Mook, while its yield was lower than that of sea mustard Mook.

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균질 처리가 막걸리 고형분의 현탁 안정성에 미치는 영향 (Effect of Homogenization on Suspension Stability of Makgeolli)

  • 신제영;강창수;최한석
    • 현장농수산연구지
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    • 제23권2호
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    • pp.33-41
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    • 2021
  • The effect of homogenization treatment on the suspension stability of makgeolli was evaluated. The non-soluble solids of makgeolli that were not homogenized were precipitated at 1.0-68 mm after 10 minutes of standing and 2.0-70.5 mm after 30 minutes of standing. On the other hand, in the makgeolli homogenized with a blender for more than 20 seconds, no precipitated non-soluble solids were observed during the initial 10 minutes, and when it was left still for 30 minutes, it showed precipitation of 2.0 mm (control 58.0 mm). The makgeolli treated with a high-pressure homogenizer did not show any sedimentation until 30 minutes of standing. In the sensory evaluation, the high-pressure homogenized makgeolli had a score of 3.93, whereas non-treated had a score of 2.80, which was improved by 40% by homogenization.

노치가 있는 콘크리트의 인장파괴 거동에 관한 연구 (A Study on the Tensile Failure of a Notched Concrete)

  • 이준석;최일윤;엄주환;방춘석
    • 콘크리트학회지
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    • 제9권5호
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    • pp.189-196
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    • 1997
  • 본 연구에서는 유한요소법을 이용한 콘크리트 인장균열의 발생 및 전파양상을 모형화하기 위하여 분산균열(smeared crack) 모델의 일종인 2차원 균질화된 균열(homogenized crack)모형을 제안하였다. 제안한 모형은 인장균열면을 따라 속도 불연속계(velocity discontinuity)를 도입하고 평형방정식 빛 적합방정식을 이용하여 인장균열을 포함한 콘크리트의 구성방정식을 유도할 수 있으며 인장균열이 소성연화거동을 하는 경우. 유한요소망내에서 객관성이 유지될 수 있음을 밝히기 위하여 1차원 영역내에서 엄밀해를 유도하였다. 제안한 모형을 이용한 1차원 또는 2차원 유한요소 해석은 기존의 노치를 포함한 콘크리트 시편에 대한 실험과 상응하는 결과를 보였을 뿐만 아니라 유한요소망의 객관성이 유지되고 있음을 밝혔다. 제안한 모형은 큰 어려움없이 3차원 영역으로 확대할 수 있을 것이며 이에 대한 추가적인 연구가 계속될 것이다.

저속충격을 받는 적층복합재료 평판의 미시구조를 고려한 interlaminar stress 거동 연구 (Interlaminar stress behavior of laminated composite plates under Low velocity Impact)

  • 지국현;김승조
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2005년도 춘계학술발표대회 논문집
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    • pp.249-252
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    • 2005
  • Prediction of damage caused by low-velocity impact in laminated composite plate is an important problem faced by designers using composites. Not only the inplane stresses but also the interlaminar normal and shear stresses playa role in estimating the damage caused. The work reported here is an effort in getting better predictions of damage in composite plate using DNS approach. In the DNS model, we discretize the composite plates through separate modeling of fiber and matrix for the local microscopic analysis. Through comparison with the homogenized model. In the view of microscopic mechanics with DNS model, interlaminar stress behaviors in the inside of composite materials is investigated and compared with the results of the homogenized model which has been used in the conventional approach of impact analysis.

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다채널 3T 자기공명장치에서의 Compressed B1 제어법 (Compressed B1 Control Method in Multi-channel 3 T MRI)

  • 유형석
    • 전기학회논문지
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    • 제62권8호
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    • pp.1120-1124
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    • 2013
  • Our objective of this study was to reduce radio frequency coil (RF) control time at 3 T MRI systems. A compressed method is proposed with a convex optimization and pseudo-inverse method in multi-channel RF coils. After applying the proposed methods, fields are homogenized with less field data. Even with 80% compression, the fields are well homogenized and localized, indicating that mapping requires only 20% of the original data. Detailed values are compared between each compressed result in and outside the region of interest at 3 T.

김치식빵의 제조와 품질에 관한 연구 (Studies on Preparation and Quality of Kimchi-Bread)

  • 박인경;김미경;김순동
    • 동아시아식생활학회지
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    • 제10권3호
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    • pp.229-238
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    • 2000
  • This study was conducted to investigate the effect of homogenized kimchi product (HKP) on dough characteristics and quality of bread. Fermented homogenized Chinese cabbage kimchi product was added 0.10, 20 and 30% to wheat flour. The pH of dough decreased with an increase in the amounts of HKP, which showed at PH 4.9 for the dough added 30% HKP. Fermentation time of the dough was reduced as much as 9~23 minutes as compared with the control products. Loaf volume index of the bread prepared by adding 10 ~30% HKP increased also by 12.7 ~ 19.0%. Hardness, cohesiveness, springiness and gumminess of the bread added with 30% HKP were lower than those of the control. The gas forming cell of the bread added with 30% HKP were good and regular. Crust and internal color of the bread with more HKP had tendency to redness. Sensory quality of the kimchi-bread estimated by shape, flavor and overall quality was better than that of control product, especially the kimchi-bread qualify at addition of 30% HKP was best.

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