• Title/Summary/Keyword: leaf analysis

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The Variation of Leaf Characterics in 6 Natural Populations of Stewartia koreana Nakai (노각나무 6개 천연집단(天然集團)의 엽형질(葉形質) 변이(變異))

  • Kim, Young-Jung;Kim, Kee-Chul;Lee, Byung Sil;Lee, Gab-Yeoun;Cho, Kyoung-Jin;Kang, Jin Taek;Kim, Tae-Dong
    • Journal of Korean Society of Forest Science
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    • v.94 no.6
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    • pp.446-452
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    • 2005
  • In order to examine the natural distribution variations between groups of the Stewartia koreana, the leaf form characteristics of the investigation sites were analyzed by each group. As a result, the Mt. Kumsan group showed a smaller value in leaf length, width, area, and the number of veins, but not in the petiole length and serration number. Among each character, the coefficient of variation(CV) of the characters excluding petiole length and leaf area was in a comparatively narrow range, from 11.6~17.4%. On the other hand, the CV of petiole length and leaf area between the groups was 34.9% and 28.4% respectively. The CV of these characters within the group was also extraordinary- petiole length showed 29.5~42% and leaf area showed 27.7~40.7%. Also, the simple correlation analysis between 12 leaf characteristics showed that the correlation between leaf width and leaf area was high (r=0.975). The correlations between leaf length and leaf area, between leaf length and leaf width were 0.971 and 0.969, respectively. A negative correlation between angle of leaf base and ratio of leaf length to leaf width was discovered (r= -0.843), meaning that the ratio of leaf length to leaf width decreases as angle of leaf base increases. A cluster analysis was enforced among leaf characteristics of the selected group as a standard on the similarity of quantitative, qualitative measurements. The results showed that at a 0.4 distance level, the subjects could be classified into 4 groups. Group 1 was the Mt. Jogyesan and Mt. Kayasan group, group 2 was Mt. Paegunsan, group 3 was Mt. Unmunsan and Mt. Mudungsan, and group 4 was Mt. Kumsan. At a distance level of 0.6, the subjects were classified into two groups. Group 1 was the Mt. Ktimsan group and group 2 was Mt. Mudungsan, Unmunsan, Paegunsan, Kayasan, and Cogyesan. Especially the Mt. Kumsan group had the smallest value in the leaf characteristics of leaf length, width, area, and the number of veins, showing an obvious difference from the other five groups. There were five principal components that had a meaningful eigenvalue over 1.0 among the 12 extracted components. The explanatory power of the top two main components (leaf length and width) on the total variation was 52.7%. The explanatory power was 91.3% when all 5 main components were included.

Quality Characteristics of White Pan Bread with Cudrania tricuspidata Leaf Powder (꾸지뽕잎 분말을 첨가한 식빵의 품질 특성)

  • Kim, Eunji;Ju, Hyoung-Woog
    • Culinary science and hospitality research
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    • v.22 no.7
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    • pp.173-186
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    • 2016
  • This study was conducted to investigate quality characteristics of white pan bread with Cudrania tricuspidata leaf powder having functional components. Mixograph, pH, TPA, volume, specific volume, moisture, CrumbScan, color value, sensory evaluation and shelf-life test were performed on the white pan bread with Cudrania tricuspidata leaf powder. The obtained results are as follows. Mixogram analysis results showed that the dough with Cudrania tricuspidata leaf powder was suitable for baking quality. The more Cudrania tricuspidata leaf powder was added in the dough, the higher dough pH was and the lower pH values after fermentation and of the final productwere. TPA analysis results showed that higher amounts of Cudrania tricuspidata leaf powder resulted in increased hardness, chewiness, and gumminess of the white pan bread. Volume and specific volume of white pan bread were decreased with increased amounts of Cudrania tricuspidata leaf powder. CrumbScan images showed that fineness of grain, crust thickness, and volume of the bread were significantly different depending on the amount of Cudrania tricuspidata leaf powder. While color value analysis showed that increasing the amount of Cudrania tricuspidata leaf powder resulted in low L and a values. The results of the acceptance test showed that CLP3 had better scores in the appearance and texture characteristics than the control, while taste and overall acceptance were higher in the CLP2 compared with the control. According to the results of the shelf-life test, the white pan bread with 1~2% of Cudrania tricuspidata leaf powder had a significantly lower hardness when compared with the control. It was judged that a lower amount of Cudrania tricuspidata leaf powder could help in maintaining the softness of bread crumbs. Moisture content in the white pan bread decreased with the increased amounts of Cudrania tricuspidata leaf powder, but there were no significant differences among specimens.

A Study on the Anisotropic Flow Characteristics of Droplets on Rice Leaf Surface (벼 잎 표면에서 액적의 이방성 흐름 특성에 관한 연구)

  • Kim, Tae Wan
    • Tribology and Lubricants
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    • v.33 no.6
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    • pp.251-255
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    • 2017
  • In this study, we aimed to clarify the wettability and anisotropic flow characteristics of rice leaves as a basic study for engineering applications of anisotropic flow characteristics of rice leaf surface. To investigate the surface structure of rice leaf, the micro grooves and asperities of rice leaves were analyzed and quantified by scanning electron microscope, Confocal laser scanning microscopy, and stylus profilometer. The analysis of the structure of rice leaf surface confirmed that asymmetrical cone - like protrusions in leaf veins were inclined toward the leaf tip. The static contact angle test showed that the contact angle at the midline vein or leaf vein location where the micropapilla is concentrated is about $20^{\circ}$ higher than the leaf blade position. The contact angles of fresh and dried rice leave were also compared. The dried rice leaves showed a contact angle of about $5^{\circ}$ to $15^{\circ}$ higher than that of fresh leaves, suggesting that the volume of the protrusions decreased as the water was removed, thus reducing the contact area with the droplet. In the contact angle history test the hysteresis in the leaf tip direction was found to be much lower than that in the leaf petiole direction. This results can be explained that asymmetrical cone - like protrusions had a significant effect on the droplet flow characteristics through contact angle hysteresis experiment.

Estimation Model and Vertical Distribution of Leaf Biomass in Pinus sylvestris var. mongolica Plantations

  • Liu, Zhaogang;Jin, Guangze;Kim, Ji Hong
    • Journal of Korean Society of Forest Science
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    • v.98 no.5
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    • pp.576-583
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    • 2009
  • Based on the stem analysis and biomass measurement of 36 trees and 1,576 branches in Pinus sylvestris var. mongolica (Mongolian pine) plantations of Northeast China, this study was conducted to develop estimation model equation for leaf biomass of a single tree and branch, to examine the vertical distribution of leaf biomass in the crown, and to evaluate the proportional ratios of biomass by tree parts, stem, branch, and leaf. The results indicated that DBH and crown length were quite appropriate to estimate leaf biomass. The biomass of single branch was highly correlated with branch collar diameter and relative height of branch in the crown, but not much with stand density, site quality, and tree height. Weibull distribution function would have been appropriate to express vertical distribution of leaf biomass. The shape parameters from 29 sample trees out of 36 were less than 3.6, indicating that vertical distribution of leaf biomass in the crown was displayed by bell-shaped curve, a little inclined toward positive side. Apparent correlationship was obtained between leaf biomass and branch biomass having resulted in linear function equation. The stem biomass occupied around 80% and branch and leaf made up about 20% of total biomass in a single tree. As the level of tree class was increased from class I to class V, the proportion of the stem biomass to total biomass was gradually increased, but that of branch and leaf became decreased.

Quality Characteristics of Cookies Added with Ginseng Leaf (인삼 잎을 첨가한 쿠키의 품질 특성)

  • Kim, Dam;Kim, Kyoung-Hee;Yook, Hong-Sun
    • Korean journal of food and cookery science
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    • v.30 no.6
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    • pp.679-686
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    • 2014
  • This study was carried out to evaluate the quality characteristics of cookies added with various concentrations (0, 1, 3 and 5%) of ginseng leaf powder. The pH of the cookies significantly decreased with increased ginseng leaf powder concentrations (p<0.05), but the density of cookies showed no significant differences. Spread factor, loss rate, and leaving rate of cookies decreased according to the amount of added ginseng leaf powder. The lightness and yellowness of cookies decreased as the concentration of the ginseng leaf powder increased whereas no significant difference in the redness was found with increased ginseng leaf concentration. In the texture analysis, the hardness of the cookies increased according to the concentration of ginseng leaf. DPPH free radical scavenging activity of the cookies significantly increased with increased ginseng leaf concentration (p<0.05). In the sensory evaluation, sensory scores for color, taste and overall acceptability were highest in the 3% ginseng leaf cookies. Thus, our results suggested that the optimum amount of ginseng leaf powder to add to cookies was 3%.

Uncertainty of Measurement in Nitrate Analysis from Burley Leaf Tobacco (버어리종 담배 중 질산성 질소에 대한 측정불확도)

  • Lee Jeong-Min;Lee Kyoung-Ku;Han Sang-Bin
    • Journal of the Korean Society of Tobacco Science
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    • v.27 no.2
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    • pp.226-234
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    • 2005
  • The uncertainty of measurement in nitrate from burley leaf tobacco by continuous-flow analysis method was evaluated following internationally accepted guidelines. The sources of uncertainty associated with the analysis of nitrate were weight of standard and sample, purity of standard, dilution of standard solution, calibration curve, water content, etc. The calculation of uncertainty based on the GUM(Guide to the Expression of Uncertainty in Measurement) and EURACHEM/CITAC Guide. An expanded uncertainty was obtained by multiplying the combined standard uncertainty with a coverage factor (k) calculated from the effective degree of freedom. The concentration of nitrate from burley leaf tobacco was $2.09\%$ and the expanded uncertainty by multiplying by the coverage factor(k, 2.20) was $0.13\%\;at\;a\;95\%$ confidence level.

Elastic Stiffness Analysis of Leaf Type Holddown Spring Assemblies (판형홀드다운 스프링 집합체의 탄성 강성도 해석)

  • Lim, Hyun-Tae;Kim, Jae-Won;Song, Kee-Nam
    • Nuclear Engineering and Technology
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    • v.27 no.5
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    • pp.760-766
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    • 1995
  • A general method is proposed for elastic stiffness analysis of the leaf type holddown springs using only the geometric data and Young's modulus of the springs. In this method, an engineering beam theory and Castigliano's theory are applied to elastic stiff analysis of the leaf type holddown springs. To show reliability and effectiveness of this method, the elastic stiffness from the proposed method is compared with test result and from the comparison, the unposed method has been proven to be effective for estimating the elastic stiffness of the leaf springs.

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Little Leaf and Yellowing Symptoms on Castanea crenata are Associated with Phytoplasma in Korea

  • Eun Ju Cheong
    • Journal of Forest and Environmental Science
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    • v.39 no.1
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    • pp.49-54
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    • 2023
  • For unknown reasons, a few trees in a private chestnut orchard in Icheon si, Gyunggi-do suffered leaf chlorosis and growth decline. Based on symptoms, phytoplasma was a probable cause. Leaf samples were collected from two symptomatic and non-symptomatic trees in the orchard for phytoplasma detection. An amplicon of about 1.2 bp size was obtained from both symptomatic trees by PCR with the universal 16S rDNA primers. Sequences of these amplicons were found to have 99% nucleotide sequence identity to the corresponding genomic region of 16SrIII (X-disease group). More than 100 phytoplasma isolates, such as Candidatus phytoplasma pruni, Milkweed yellows phytoplasma, Goldenrod yellows phytoplasma, Tsuwabuki witches'-broom phytoplasma, Candidatus Phytoplasma trifolii, etc. were involved in the list. Phylogenetic analysis revealed that the sequence obtained in this study closely clustered with Candidatus phytoplasma groups. While one of the amplicons shared 91% identity with the Candidatus phytoplasma castaneae, the other shared only 47%. It needs further analysis and investigation to determine the exact taxonomy. Meanwhile, based on the analysis of the sequences, chlorosis, and small leaves were associated with phytoplasma.

An Efficient Method for Calculating Nonlinear Stiffness of the Progressive Multi-Leaf Spring (Progressive Multi-Leaf Spring의 비선형 강성해석 법)

  • Kim, Sung-Soo;Moon, Won-Kyu;Yoo, Young-Il
    • Proceedings of the KSME Conference
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    • 2000.11a
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    • pp.413-419
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    • 2000
  • An efficient method for calculating the nonlinear stiffness of the Progressive Multi-Leaf Spring is developed and evaluated. It utilizes the interaction between the main and help spring that induces the nonlinearity. The main and the help springs are modeled as multi-leaf cantilever beams, and, then, they are integrated as one by connecting the two models for each side of the Progressive Multi-Leaf Spring at the center-bolt. The results from the developed model are evaluated by use of the commercial FEA program, ABAQUS. The nonlinear spring coefficients calculated by FEM analysis yield the numbers very close to the numbers calculated for the spring coefficients by used of the developed method. From the comparative evaluations, the developed method is accurate enough and very efficient in calculation time for evaluating the nonlinear spring property of the Progressive Multi-Leaf Spring.

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A Study on the Lift-off Characteristics of an Air-lubricated Multi-leaf Foil Journal Bearing (공기윤활 다엽포일 저널 베어링의 회전축 부상 특성에 관한 연구)

  • 이용복;김태호;김창호;이남수;장건희
    • Tribology and Lubricants
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    • v.17 no.4
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    • pp.290-296
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    • 2001
  • Lift-off means that the rotating journal surface separates from the leaf surface in an air-lubricated multi-leaf foil journal bearing. Lift-off builds up minimum film thickness which will provide load capacity between leaves and journal. In this paper an analysis of air-lubricated multi-leaf foil journal bearing was performed with effects of multi-leaf foil deflection and compressible lubrication equation simultaneously. Minimum film thickness built up versus journal speed predicts the lift off characteristics and these results will be useful in designing and selecting the proper speed of the air-lubricated multi-leaf foil journal bearing.