• 제목/요약/키워드: texture analyses

검색결과 168건 처리시간 0.032초

알루미늄 판재의 이방성거동 예측을 위한 현상학적 모델과 결정소성학적 모델의 비교연구 (Study on Phenomenological and Crystal Plasticity Models to Predict Anisotropic Behaviors for Aluminum Alloy Sheets)

  • 정완진;윤정환
    • 소성∙가공
    • /
    • 제15권8호
    • /
    • pp.574-580
    • /
    • 2006
  • Anisotropy has an important effect on the strain distribution in aluminum alloy sheet forming, and it is closely related to the thinning and formability of sheet metals. Thus, the anisotropy of the material should be properly considered for the realistic analyses of aluminum sheet forming processes. For this, anisotropy can be approached in two different scales: phenomenological and microstructural (polycrystal) models. Recent anisotropic models (Yld2000-2d; Barlat et al.[1] 2003, Cuitino et al.[2] 1992) were employed in this work. For the simulation using shell element, the method which can impose plane stress condition in the polycrystal model is developed. Lankford values and yield stress ratios are calculated along various directions. As planar anisotropic behavior, a circular cup deep drawing simulation was carried out to compare the phenomenological and microstructure models in terms of earing profile.

The effect of constitutive spins on finite inelastic strain simulations

  • Cho, Han Wook;Dafalias, Yannis F.
    • Structural Engineering and Mechanics
    • /
    • 제5권6호
    • /
    • pp.755-765
    • /
    • 1997
  • Within the framework of anisotropic combined viscoplastic hardening formulation, accounting macroscopically for residual stress as well as texture development at finite deformations of metals, simple shear analyses for the simulation of fixed-end torsion experiments for ${\alpha}$-Fe, Al and Cu at different strain rates are reviewed with an emphasis on the role of constitutive spins. Complicated responses of the axial stresses with monotonically increasing shear deformations can be successfully described by the capacity of orthotropic hardening part, featuring tensile axial stresses either smooth or oscillatory. Temperature effect on the responses of axial stresses for Cu is investigated in relation to the distortion and orientation of yield surface. The flexibility of this combined hardening model in the simulation of finite inelastic strains is discussed with reference to the variations of constitutive spins depending upon strain rates and temperatures.

고온압출한 AZ 31 마그네슘 합금의 압축변형 중 집합조직과 미세조직의 발달 (Development of Textures and Microstructures during Compression in a Hot-Extruded AZ31 Mg Alloy)

  • 정병조;이명재;박용범
    • 대한금속재료학회지
    • /
    • 제48권4호
    • /
    • pp.305-314
    • /
    • 2010
  • The development of textures and microstructures during plastic deformation in a hot-extruded AZ 31 Mg alloy was investigated using a compression test with such parameters as deformation temperature, strain rate. It was observed from true stress-strain curves that twinning involves changes of the flow stresses. In the early stages of deformation at temperatures lower than $200^{\circ}C$, the occurrence of twins resulted in a decrease of the work-hardening rate, which increased drastically at a true strain of -0.05. The evolution of the deformation textures were assessed with the aid of EBSD analyses in terms of the competition between twinning and slip activity.

Compositional Change of MgO Barrier and Interface in CoFeB/MgO/CoFeB Tunnel Junction after Annealing

  • Bae, J.Y.;Lim, W.C.;Kim, H.J.;Kim, D.J.;Kim, K.W.;Kim, T.W.;Lee, T.D.
    • Journal of Magnetics
    • /
    • 제11권1호
    • /
    • pp.25-29
    • /
    • 2006
  • Recent experiments have demonstrated high TMR ratios in MTJs with the MgO barrier [1,2]. The CoFeB/MgO/CoFeB junctions showed better properties than the CoFe/MgO/CoFe junctions because the MgO layer had a good crystalline structure with (001) texture and smooth and sharp interface between CoFeB/MgO [3]. The amorphous CoFeB with 20 at%B starts the crystallization at $340^{\circ}C$ [4] and this crystallization of the CoFeB helps obtaining the high TMR ratio. In this work, the compositional changes in the MgO barrier and at the interface of CoFeB/MgO/CoFeB after the CoFeB crystallization were studied in annealed MTJs. XPS depth profiles were utilized. TEM analyses showed that the MgO barrier had (100) texture on CoFeB in the junctions. B in the bottom CoFeB layer diffused into the MgO barrier and B-oxide was formed at the interface of CoFeB/MgO/CoFeB after the CoFeB crystallization.

부추 분말 첨가 머핀의 제조 조건 최적화 (Optimization of Muffins Containing Dried Leek Powder Using Response Surface Methodology)

  • 유승연;정희선;박상현;신지훈;정현아;주나미
    • 대한영양사협회학술지
    • /
    • 제14권2호
    • /
    • pp.105-113
    • /
    • 2008
  • The purpose of this study was to develop a muffin containing dried leek powder. The complete analysis was conducted using the Design Expert 7 program (Stat - Easy Co., Minneapolis, MN, USA). The leek muffins were produced with varying amounts of leek powder (A), sugar (B), and butter (C). According to response surface methodology (RSM), there were 16 experimental points, including two replicates. The leek muffin formulation was optimized using rheology and sensory analyses. For the results, a quadratic model was applied in determining lightness, volume, hardness, and sensory characteristics, including flavor, texture, and overall quality; redness and height were represented by a linear model. Lightness decreased and redness increased with increasing amounts of leek powder (p<0.001). In addition, hardness displayed significant differences (p<0.001) with increasing amounts of leek powder. The sensory evaluation results showed significant differences for color, flavor, texture, and overall quality (p<0.05). Based on the numerical and graphical methods, the optimal formulation was determined as 8.30 g of leek power, 88.37 g of sugar, and 81.70 g of butter.

  • PDF

Sensory profile and technological characterization of boneless dry-cured ham with lactulose added as a prebiotic

  • Gomes, Hewerton Barbosa;Rodrigues, Lorena Mendes;Massingue, Armando Abel;Lima, Italo Abreu;Ramos, Alcineia de Lemos Souza;Ramos, Eduardo Mendes
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제33권2호
    • /
    • pp.339-348
    • /
    • 2020
  • Objective: This study investigates the technological and sensory profile of boneless dry-cured ham with different contents of lactulose added as a prebiotic ingredient. Methods: In addition to the control samples (without the addition of lactulose), three treatments were formulated to contain 2%, 4%, or 6% lactulose. Technological (lactulose content, instrumental color and texture profile analysis) and sensory (acceptance and check-all-thatapplies tests) analyses were performed on the final product. Results: The lactulose content in the finished product (1.86%±0.23%, 3.16%±0.18%, and 2.51%±1.35%) was lower than the lactulose originally added (2%, 4%, and 6%, respectively). The addition of 4% and 6% lactulose made (p<0.05) the products darker (lower L) and redder (lower h) with higher hardness and chewiness values, when compared to control samples. The additions of 2% and 4% lactulose reduce the appearance acceptability of the products, but overall the treatments were well accepted. Conclusion: The use of up to 4% lactulose as a prebiotic in the production of boneless dry-cured hams provides an alternative to improving its nutritional value with little alteration in the technological characteristics and still meeting the sensory characteristics desired by consumers.

홍삼분말을 첨가한 설기떡의 품질특성 (Quality Characteristics of Sulgidduk Containing Added Red Ginseng Powder)

  • 신승미;정정숙;한명륜;김애정;김영호
    • 한국식품조리과학회지
    • /
    • 제25권5호
    • /
    • pp.586-592
    • /
    • 2009
  • Sulgidduk samples containing 2, 4, and 8% red ginseng powder and a control[ED highlight - consider specifying what the control was, if 0%, then change to Sulgidduk samples containing 0(control), 2, 4 and 8%] were examined for moisture content, color, gelatinization properties, textural characteristics, and sensory qualities to determine the optimal ratio of red ginseng powder in the formulation. The moisture contents among the samples did not differ significantly. Specifically, they ranged from 39.64 to 40.69%, and increased as the red ginseng powder content increased. Additionally, the lightness decreased and the yellowness and redness increased as the red ginseng powder content increased. Evaluation of the gelatinization properties revealed that the, peak viscosity(P), hold viscosity(H), final viscosity(F), setback, and time to peak viscosity decreased with increasing red ginseng powder content, but the breakdown and temperature to peak viscosity did not differ significantly among samples[ED highlight - please ensure my changes are correct]. The hardness and adhesiveness decreased with increasing red ginseng powder content, as did the cohesiveness, gumminess, and chewiness; however, the springiness did not differ significantly among samples. Sulgidduk containing 4% red ginseng received the highest scores for flavor, taste, texture and overallquality. Based on the above results of the sensory and texture analyses, Sulgidduk containing 4% red ginseng had the highest quality[ED highlight - please ensure my changes are correct].

Transrectal Real-time Tissue Elastography - An Effective Way to Distinguish Benign and Malignant Prostate Tumors

  • Zhang, Yan;Tang, Jie;Liang, Hai-Dong;Lv, Fa-Qin;Song, Zhi-Gang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권4호
    • /
    • pp.1831-1835
    • /
    • 2014
  • Background: To investigate the relationship between extracellular matrix parameters and texture of prostatic lesions evaluated by transrectal real-time tissue elastography (TRTE). Methods: 120 patients suspicious for prostate cancer underwent TRTE. Targeted biopsies were carried out after 12-core systematic biopsy. Epithelia were stained with hematoxylin-eosin, and Victoria blue and Ponceau S were used to stain elastic-collagen fibers, and picric acid-sirius red for visualization of collagen type I (Col1) and III (Col3). Smooth muscles were visualized by immunohistochemistry. All image analyses were performed in a blind manner using Image Pro Plus 6.0, and the area ratios of epithelium, elastic fibers, collagen fibers and Col1/Col3 were determined. Results: 42 patients with typical elastograms were included in the final data analysis. Significant differences were detected between the benign and malignant groups in the area ratios of epithelium (P = 0.01), smooth muscles and Col1/Col3 (P = 0.04, P = 0.02, respectively). There were no significant differences in the area ratios of epithelium, smooth muscle and elastic fibers between the stiff and soft lesion groups. The area ratio of Col1 was ($0.05{\pm}0.03$) in the stiff group, and ($0.02{\pm}0.01$) in the soft group (P= 0.00). However, the area ratio of Col3 was ($0.03{\pm}0.02$) in the stiff group, and ($0.05{\pm}0.04$) in the soft group (P = 0.16). Col1/Col3 in the stiff group ($1.99{\pm}1.59$) was greater than in the soft group ($0.71{\pm}0.64$) (P = 0.01). Conclusions: Tissue hardness of prostatic tumors was mainly dependent on the Col1 content, Col1/Col3 being higher in malignant than in benign lesions, so the prostate tissue texture can be used as a target for distinguishing between the two with TRTE.

KODOS-89 지역 망간단괴의 성인과 분포 (Origin of Manganese Nodules and Their Distribution in the KODOS-89 Area, Northeastern Equatorial Pacific.)

  • 정회수;정갑식
    • 한국해양학회지
    • /
    • 제25권4호
    • /
    • pp.189-204
    • /
    • 1990
  • 태평양 클라리온-클리퍼톤 균열대 서부의 KODOS(Korea Deep Ocean Study)지역에 분포하는 망간단괴의 성인과 분포, 그리고 분포 원인을 규명하기 위하여 망간단괴와 퇴적물을 채취하여 화학 및 광물학적 분석을 하였다. 이 지역의 망간단괴는 Mn/Fe 비 가 크고 구리, 니켈, 아연, 마그네슘, 토도로카이트 함량이 높으며 표면조직이 거친 속성기원의 망간단괴(S-형 망간단괴)와 철, 코발트, 버나다이트 함량이 높고 표면조직 이 매끈한 수성기원의 망간단괴(S-형 망간단괴) 그리고 화학 및 광물조성과 표면조직 이 두 기원의 중간성격을 띄는 망간단괴(R-S-형 망간단괴)로 구분된다. 성인 및 부존 밀도 등의 특성에 따라 KODOS-89 지역은 크게 4지역으로 구분된다. 즉, 부존밀도가 10 kg/m$^2$이하이고 수성기원의 망간단괴가 분포하는 최북단지역, 부존밀도가 1 kg/m$^2$ 내 외이고 속성기원의 망간단괴가 분포하는 남부 지역, 그리고 부존밀도가 10 kg/m$^2$ 이 상으로 높고 수성기원의 망간단괴가 분포하는 해저산지역으로 구분된다. 이러한 망간 단괴의 분포특성은 주로 위도에 따른 수층의 생산성 및 해저지형의 차이에 의해 기인 되었다고 생각된다.

  • PDF

발아현미분을 첨가한 식빵의 품질 특성 (Quality characteristics of the bread with sprouted brown rice flour)

  • 최지호
    • 한국식품조리과학회지
    • /
    • 제17권4호
    • /
    • pp.323-328
    • /
    • 2001
  • 본 연구에서는 발아현미의 자연식품으로써의 이용효과를 극대화 시켜 이를 이용한 기능성 식빵을 제조하기 위해 발아현미분을 첨가하여 식빵을 제조하고 부피, 무게를 측정하여 제빵 특성을 측정하였으며, 식빵의 성분변화를 살펴보기 위해 일반성분, 환원당, 아미노산, 무기질, 지방산 분석을 행하여 영양성분을 분석하고, 관능검사를 실시하였다. 발아된 현미분 첨가량 증가에 따른 제빵특성을 살펴보면, 대조구에 비하여 현미분 10∼30% 첨가 식빵의 경우 완만하게 부피가 감소하였고, 40% 첨가구는 75.48%, 50% 첨가구는 66.29%로 감소하여 빵의 외형이 허물어지는 결과를 보였으며, 현미분양의 증가에 따른 식빵 무게의 큰 변화는 찾아볼 수 없었고, 발아 현미분의 첨가량은 30%정도까지가 적정한 제빵특성을 나타내는 것을 알 수 있었다. 일반성분, 구성 아미노산 함량의 변화는 발아현미분의 첨가량이 증가함에 따라 회분, 단백질, 지방, 환원당, 섬유소 및 구성 아미노산의 함량이 계속적으로 증가하였으나, 무기질, 지방산 함량은 대조군과 비교하여 큰 차이가 없었다. 발아현미분을 혼합하여 제조한 빵의 관능적인 성질은 발아현미분의 첨가량이 많을수록 대조군에 비하여 색, 외관, texture, 입안에서의 느낌에 대한 기호도는 약간 낮았으나, 씹을수록 느껴지는 고소한 맛과 향이 대조군에 비해 좋은 특성을 나타내어 빵에 대한 전체적인 선호도는 발아현미분 첨가량이 많을수록 더 높았다.

  • PDF