• Title/Summary/Keyword: A/B Ratio

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Impact Performance of 3D Orthogonal Composites by Automated Tape Placement Process (자동적층 공정에 의한 3차원 직교 섬유배열구조 복합재의 충격특성)

  • Song S-W;Lee C-H;Um M-K;Hwang B-S;Byun J-H
    • Composites Research
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    • v.18 no.3
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    • pp.38-46
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    • 2005
  • In order to characterize the outstanding performance of three-dimensional (3D) composites, the low velocity impact test has been carried out. 3D fiber structures have been achieved by using the automated tape placement (ATP) process and a stitching method. Materials for the ATP and the stitching process were carbon/epoxy prepreg tapes and Kevlar fibers, respectively. Two-dimensional composites with the same stacking sequence as 3D counterparts have also been fabricated for the comparison of damage tolerance. For the assessment of damage after the impact loading, specimens were subjected to C-Scan nondestructive inspection. Compression after impact (CAI) tests were conducted to evaluate residual compressive strength. The damage area of 3D composites was greatly reduced $(30-40\%)$ compared with that of 2D composites. Although the CAI strength did not show drastic improvement for 3D composites, the ratio of retained strength was $5-10\%$ higher than 2D samples. The effect of stitching on the impact performance was negligible above the energy level of 35 Joules.

Physical and Sensory Characteristics of Sponge Cake with Added Broccoli (Brassica oleracea var. italica Plenck) Powder (브로콜리 첨가 스폰지 케이크의 품질 특성 연구)

  • Lim, Eun-Jeong;Lee, Hyun-Sun;Lee, Yoo-Hyun
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.6
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    • pp.873-880
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    • 2010
  • The purpose of this study was to investigate the quality characteristics of sponge cake with broccoli (Brassica oleracea var. italica Plenck) powder. Broccoli powder was mixed with wheat flour at various ratio (3, 5, 7, 9%, w/w) for physical and sensory evaluations. The specific gravity of bread dough increased with added broccoli powder. The moisture of the sponge cakes with added broccoli powder was higher than that of control. In the crumb color values, lightness (L) and redness (a) decreased upon broccoli powder addition, whereas yellowness (b) significantly increased (p<0.05). In the texture analysis hardness, cohesiveness, springiness and gumminess were reduced by addition of broccoli powder. When we evaluated the sensory characteristics of five subareas (color, flavor, texture, taste, and overall acceptability), 7% broccoli sponge cake showed the highest sensory properties except for flavor (p<0.05). Therefore, the results suggested that 7% broccoli sponge cake could be helpful in improving physical quality and taste.

Gaussian Noise Reduction Method using Adaptive Total Variation : Application to Cone-Beam Computed Tomography Dental Image (적응형 총변이 기법을 이용한 가우시안 잡음 제거 방법: CBCT 치과 영상에 적용)

  • Kim, Joong-Hyuk;Kim, Jung-Chae;Kim, Kee-Deog;Yoo, Sun-K.
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.1
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    • pp.29-38
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    • 2012
  • The noise generated in the process of obtaining the medical image acts as the element obstructing the image interpretation and diagnosis. To restore the true image from the image polluted from the noise, the total variation optimization algorithm was proposed by the R.O. F (L.Rudin, S Osher, E. Fatemi). This method removes the noise by fitting the balance of the regularity and fidelity. However, the blurring phenomenon of the border area generated in the process of performing the iterative operation cannot be avoided. In this paper, we propose the adaptive total variation method by mapping the control parameter to the proposed transfer function for minimizing boundary error. The proposed transfer function is determined by the noise variance and the local property of the image. The proposed method was applied to 464 tooth images. To evaluate proposed method performance, PSNR which is a indicator of signal and noise's signal power ratio was used. The experimental results show that the proposed method has better performance than other methods.

The short-term storage characteristics of cut kimchi cabbages treated with Ca2+ (Ca2+처리 절단배추의 소포장 단기 저장 특성)

  • Kim, Sang-Seop;Seong, Gi-Un;Hwang, Hee-Young;Jeong, Moon-Cheol;Chung, Shin-Kyo
    • Food Science and Preservation
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    • v.21 no.2
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    • pp.157-162
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    • 2014
  • To enhance the commercialization of fresh cut kimchi cabbage, the short-term storage effect of cut kimchi cabbage treated with $Ca^{2+}$ was studied. Cut kimchi cabbages ($3{\times}3$ cm) were treated with 2% calcium chloride (Ca), ascorbic acid (As), citric acid (Ct), and calcium chloride and citric acid (Ca/Ct), were put inside LDPE bags, and stored at $5^{\circ}C$ for 6 weeks. The weights reduced about 0.13~0.72%, and the ratio was the lowest in the Ca/Ct treatment. The reduction ratios of soluble soilds were 18.85~35.00%, and were the lowest in the Ca/Ct treatment. The titratable acidity decreased in all the treatments. The L values decreased, but a and b values of Hunter colorimeter increased in all the treatments. The preference for Ca/Ct treatment was the highest among all the treatments in the sensory evaluation. The marketing shelf-life of cut kimchi cabbage can be prolonged by the combination treatment of $Ca^{2+}$ and citric acid.

Changes in the Quality Characteristics of Mung Bean Starch Jelly with White Lotus(Nelumbo nucifera) Root Powder Added (연근가루를 첨가한 청포묵의 품질 특성 변화)

  • Park, Jin-Hee;Kim, Eun-Mi
    • Culinary science and hospitality research
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    • v.16 no.1
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    • pp.180-190
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    • 2010
  • This study investigates the quality characteristics of mung bean starch Jelly by addition of different ratios of white lotus(Nelumbo nucifera) root powder during 5 days of storage at $4^{\circ}C$. The moisture content of the samples ranged from 86.78 to 88.88%. The L value of the samples decreased as the amount of white lotus root powder increased; however, the a value and b value were significantly(p<0.05) increased. For the sensory evaluation, color and taste were decreased as the amount of white lotus root powder increased. Flavor and shine were not significantly different among the samples. And clarity and elasticity were highest in the sample with no powder and 5% of white lotus root powder. Hardness was decreased(p<0.05) as the amount of white lotus root powder increased. Overall acceptability was highest when using 0% and 5%. Texture profiles of hardness decreased as the amount of white lotus root powder increased. Hardness, gumminess, chewiness were found to drop significantly(p<0.05) after one day of storage. Cohesiveness was not significantly different among the samples according to the amounts of white lotus root powder. Adhesiveness was not significantly different in 0, 5, 10, and 15% of white lotus root powder. Syneresis was increased during the storage period. From the result, the most advisable mixture ratio of mung bean starch jelly with white lotus root powder was 19 g of mung bean starch, 1g of white lotus root, 0.1 g of salt and 160 mL of water.

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Quality Characteristics of Cookies added with Dropwort Powder (미나리 분말을 첨가한 쿠키의 품질특성)

  • Lee, Won-Gab
    • Culinary science and hospitality research
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    • v.21 no.4
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    • pp.42-54
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    • 2015
  • The purpose of this study was to investigate the quality characteristics of cookies prepared with dropwort powder(0, 2, 4, 6, and 8%) for flour. The bulk density of cookie dough of groups with dropwort powder shows significantly differences when compared to the control group. The pH of cookie dough and cookies were decreased by addition of dropwort powder. The moisture content of the groups with dropwort powder was higher than that of the control group. The weight and width of the groups with dropwort powder was lower than those of the control group. The spread ratio of the groups with dropwort powder was lower but the loss rate of cookies was higher than those of the control group. In color, the L, a, and b value was decreased significantly by addition of dropwort powder. The hardness of the groups with 2% and 4% dropwort powder was higher than that of the control group. DPPH radical scavenging activity of the control group was 20.62%, whereas the groups with dropwort powder ranged from 32.11~65.10%. Sensory evaluation scores in terms of appearance, flavor, taste, texture, and overall preference of groups with 2% and 4% of dropwort powder did not show any significantly differences when compared to the control group. Based on the above results, using less than 4% of the dropwort powder would be proper to make cookies.

Suitability of Various Domestic Wheats for Korean-Style Steamed Bread (한국형 찐빵 제조시 국내산 밀 품종의 적합성)

  • 김창순;황철명;김혁일;정동진;한재홍
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.6
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    • pp.1129-1136
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    • 2001
  • This study was to investigate the suitability of six domestic wheat cultivars for the Korean-style steamed bread made under optimal conditions. Six wheat flours milled from cultivars of Greu, Kumgang, Eunpa, Taptong Kobun, and Allgreu contained 13.8, 13.7, 13.7, 13.0, 11.7, 11.0% of protein. Control bread was made from blend (protein 10.5%) of 50% high strength and 50% low strength wheat flours milled from imported wheats. The volume of steamed bread made from Kumgang was highest followed by Eunpa, Tapdong, Kobun, Greu, control bread, Allgreu. Especially, the bread qualities of Kumgand and Kobun were superior to the control bread, showing better surface characteristics such as smoothness, glossiness, and whiteness, better shapes and desirable texture. Domestic wheat flours, having medium strength with high protein content above 13.0% were suitable for steamed bread except for Greu. Volumes of steamed bread made from domestic wheat flours were correlated with protein and ash content, flour color (L value), farinograph dough development time and stability, whereas spread ratio, total bread score and overall acceptability were correlated with farinograph dough stability It is concluded that flour quality is more important factor than protein content when domestic wheat flours are chosen for Korean-style steamed bread

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The Study of Magnetic Structure of Ni1-xMgxFe2O4 Ferrite System by Mössbauer Spectroscopy (Mössbauer 분광법에 의한 Ni1-xMgxFe2O4 Ferrite의 자기구조 연구)

  • Yoon, In-Seop;Baek, Seung-Do
    • Journal of the Korean Magnetics Society
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    • v.19 no.3
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    • pp.106-112
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    • 2009
  • $Ni_{1-x}Mg_xFe_2O_4$ ferrite system was studied by using X-ray diffraction and $M{\ddot{o}}ssbauer$ spectroscopy. The samples were prepared by ceramic sintering method with Mg content x. The X-ray diffraction patterns of samples show phase of cubic spinel structure. There are no remarkable changes of lattice constants in $Ni_{1-x}Mg_xFe_2O_4$ ferrite system. The $M{\ddot{o}}ssbauer$ spectra were consisted of two sets of six lines, respectively, corresponding to $Fe^{3+}$ at tetrahedral and octahedral sites. The magnetic hyperfine field of samples was decreased as increasing Mg contents x in both sites and it was shown Yafet-Kittel magnetic structure. $NiFe_2O_4$ was shown complete inverse spinel, but $NiFe_2O_4$ was shown partial inverse spinel which absorption area ratio (oct/tet) was 1.449 in $M{\ddot{o}}ssbauer$ spectrum.

Quality Properties of Jujube Yakju Based on the Adding Rate of Dried Jujube and Storage Periods (건조대추 첨가비율 및 저장기간에 따른 대추약주의 품질특성)

  • Choi, Jeong-Sil;Yeo, Soo-Hwan;Choi, Ji-Ho;Choi, Han-Seok;Jeong, Seok-Tae
    • Food Science and Preservation
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    • v.20 no.1
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    • pp.52-61
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    • 2013
  • This study was conducted not only to investigate the effects of rate of addition of dried jujube to Yakju (0, 0.5, 1.0, 1.5, 2.0 percent) but also to examine the quality changes in jujube Yakju during its storage (for 75 days at $35^{\circ}C$). The results showed no significant differences in pH, total acidity, soluble solids, and anthocyanin and alcohol contents of the Yakju right after its fermentation. With the increase in the amount of jujube that was added, the lightness of the jujube Yakju changed from 93 to 94, its redness decreased, and its yellowness significantly increased. The jujube Yakju that was fermented with 1.5-percent dried jujube had high sensory evaluation (selection rate) scores for color, flavor, taste and overall acceptability. It had no significant changes in pH and total acidity during its storage after its heat treatment. Its soluble solids contents tended to decrease with its heat treatment and to increase in its storage period. With respect to its color changes during its storage, the higher the ratio of the jujube that was added, the longer the storage period was, the lightness (L) and redness (a) decreased and the yellowness (b) increased. The polyphenol contents depended on the rate of addition of the dried jujube, but were not affected by the heat treatment and storage period. The organic acids in jujube Yakju were citric acid, succinic acid, lactic acid, malic acid and acetic acid.

Synthesis of the orange color pigment in the system of TiO2-SnO-ZnO by solid state reaction (고상반응법에 의한 TiO2-SnO-ZnO의 주황 안료 합성에 관한 연구)

  • Kim, Soomin;Kim, Ungsoo;Cho, Woo Seok
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.26 no.5
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    • pp.181-187
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    • 2016
  • In this study, new composition of orange color pigment was developed by replacing formerly used lead and chromium with environment-friendly elements. $TiO_2-SnO-ZnO$ composite was synthesized using the solid state reaction under the reducing atmosphere with the LPG and air mixture gas. The synthesized pigments were characterized by spectrophotometer, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS). The colorimetric analysis of pigments exhibited color values ranging from yellow to orange-red. Five different crystalline phases were formed after the heat treatment for 4 and 6 hours. The color of pigments was strongly influenced by the crystalline structure of $SnO_2$, having either cubic or tetragonal structure. The oxidation state study of elements revealed that the color of pigment is getting close to rYR with the increase of $Sn^{4+}$ ratio.