• Title/Summary/Keyword: Morphological Structure

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The Effect of Electron Beam Irradiation on Chemical and Morphological Properties of Hansan Ramie Fibers

  • Lee, Jung Soon
    • Fashion & Textile Research Journal
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    • v.15 no.3
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    • pp.430-436
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    • 2013
  • The purpose of this study investigates the effects of electron beam(EB) irradiation on the chemical and morphological properties of Hansan ramie fiber. Hansan ramie fibers were irradiated with electron beam doses of 0, 1, 3, 5 and 10kGy. The effect of electron beam irradiation on the chemical components of fibers as well as the surface chemical and morphological properties were investigated using chemical component analysis methods based on TAPPI standards, XPS, and SEM. The results indicate that the surface layers can be removed under suitable EB irradiation doses. Alcohol-benzene extraction and lignin content increases gradually with an increase in EB irradiation and reaching a maximum at an EB dose of 3kGy, and decreases at 10kGy. The surface chemical changes measured by XPS corresponded to the chemical composition analysis results. The C1 peak and the O/C ratio decreased with the removal of the multi-layer and primary layer by EB irradiation. The SEM images show the inter-fibrillar structure etched by EB irradiation up to 5kGy. At 10kGy, the surface structure of the ramie fiber shows highly aligned and distinctive striations in a longitudinal direction. The removal of these exterior layers of the fiber was confirmed by changes in surface morphology as observed in SEM images.

Use of the Quantitatively Transformed Field Soil Structure Description of the US National Pedon Characterization Database to Improve Soil Pedotransfer Function

  • Yoon, Sung-Won;Gimenez, Daniel;Nemes, Attila;Chun, Hyen-Chung;Zhang, Yong-Seon;Sonn, Yeon-Kyu;Kang, Seong-Soo;Kim, Myung-Sook;Kim, Yoo-Hak;Ha, Sang-Keun
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.5
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    • pp.944-958
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    • 2011
  • Soil hydraulic properties such as hydraulic conductivity or water retention which are costly to measure can be indirectly generated by soil pedotransfer function (PTF) using easily obtainable soil data. The field soil structure description which is routinely recorded could also be used in PTF as an input to reduce the uncertainty. The purposes of this study were to use qualitative morphological soil structure descriptions and soil structural index into PTF and to evaluate their contribution in the prediction of soil hydraulic properties. We transformed categorical morphological descriptions of soil structure into quantitative values using categorical principal component analysis (CATPCA). This approach was tested with a large data set from the US National Pedon Characterization database with the aid of a categorical regression tree analysis. Six different PTFs were used to predict the saturated hydraulic conductivity and those results were averaged to quantify the uncertainty. Quantified morphological description was successively used in multiple linear regression approach to predict the averaged ensemble saturated conductivity. The selected stepwise regression model with only the transformed morphological variables and structural index as predictors predicted the $K_{sat}$ with $r^2$ = 0.48 (p = 0.018), indicating the feasibility of CATPCA approach. In a regression tree analysis, soil structure index and soil texture turned out to be important factors in the prediction of the hydraulic properties. Among structural descriptions size class turned out to be an important grouping parameter in the regression tree. Bulk density, clay content, W33 and structural index explained clusters selected by a two step clustering technique, implying the morphologically described soil structural features are closely related to soil physical as well as hydraulic properties. Although this study provided relatively new method which related soil structure description to soil structure index, the same approach should be tested using a datasets containing the actual measurement of hydraulic properties. More insight on the predictive power of soil structure index to estimate hydraulic properties would be achieved by considering measured the saturated hydraulic conductivity and the soil water retention.

A Structure of Passive Constructions in Korean and their meaning 'Potential' (한국어 피동문의 구조와 가능(potential)의 의미 해석 -대조적 관점에서-)

  • Mok, Jung-Soo;Kim, Yeong-Jung
    • Lingua Humanitatis
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    • v.8
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    • pp.369-387
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    • 2006
  • Which syntactic function should we assign to the 'ga-type' constituent which occurs in the morphological passive constructions in Korean, [N0-neun N1-i Vpass-ending]? This problem is very important in two respects. First, a small change of status of the particle 'i/ga' can exert an overall influence on the Korean grammar. Second, the particle '-i/ga' cannot guarantee that 'ga-type' constituents are subject of the sentence, so that the concept of syntactic category should be distinguished from that of syntactic function. This paper claims that the analysis of sentence has long been focused on the structure of proposition, namely the argument structure and that the direction of analysis should be turned to the 'person structure' which can be revealed on the pragmatic level. On the basis of this, this paper suggests that the specific type of the morphological passive constructions in Korean, [N0-neun N1-i Vpass-ending] should be analysed in line with the psych-verb constructions and that the modal meaning 'potential' of the passive constructions is correlated with sentence pattern and 'person structure'.

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A study on object recognition using morphological shape decomposition

  • Ahn, Chang-Sun;Eum, Kyoung-Bae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1999.05a
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    • pp.185-191
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    • 1999
  • Mathematical morphology based on set theory has been applied to various areas in image processing. Pitas proposed a object recognition algorithm using Morphological Shape Decomposition(MSD), and a new representation scheme called Morphological Shape Representation(MSR). The Pitas's algorithm is a simple and adequate approach to recognize objects that are rotated 45 degree-units with respect to the model object. However, this recognition scheme fails in case of random rotation. This disadvantage may be compensated by defining small angle increments. However, this solution may greatly increase computational complexity because the smaller the step makes more number of rotations to be necessary. In this paper, we propose a new method for object recognition based on MSD. The first step of our method decomposes a binary shape into a union of simple binary shapes, and then a new tree structure is constructed which ran represent the relations of binary shapes in an object. finally, we obtain the feature informations invariant to the rotation, translation, and scaling from the tree and calculate matching scores using efficient matching measure. Because our method does not need to rotate the object to be tested, it could be more efficient than Pitas's one. MSR has an intricate structure so that it might be difficult to calculate matching scores even for a little complex object. But our tree has simpler structure than MSR, and easier to calculated the matchng score. We experimented 20 test images scaled, rotated, and translated versions of five kinds of automobile images. The simulation result using octagonal structure elements shows 95% correct recognition rate. The experimental results using approximated circular structure elements are examined. Also, the effect of noise on MSR scheme is considered.

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Modeling of Fine Sediment Transport under Multiple Breakwaters of Surface-Piercing Type

  • Lee, J. L.;Oh, M. R.
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.557-562
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    • 2004
  • A surface-piercing barrier model is presented for understanding morphological development in the sheltered region and investigating the main factors causing the severe accumulation. Surface-piercing structures like vertical barriers, surface docks and floating breakwaters are recently favored from the point of view of a marine scenario since they do not in general partition the natural sea. The numerical solutions are compared with experimental data on wave profiles and morphological change rates within a rectangular harbor of a constant depth protected by surface-piercing thin breakwaters as a simplified problem. Our numerical study involves several modules: 1) wave dynamics analyzed by a plane-wave approximation, 2) suspended sediment transport combined with sediment erosion-deposition model, and 3) concurrent morphological changes. Scattering waves are solved by using a plane wave method without inclusion of evanescent modes. Evanescent modes are only considered in predicting the reflection ratio against the vertical barrier and energy losses due to vortex shedding from the lower edge of plate are taken into account. A new relationship to relate the near-bed concentration to the depth-mean concentration is presented by analyzing the vertical structure of concentration. The numerical solutions were also compared with experimental data on morphological changes within a rectangular harbor of constant water depth. Through the numerical experiments, the vortex-induced flow appears to be not ignorable in predicting the morphological changes although the immersion depth of a plate is not deep.

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Morphological features of thermophilic activated sludge treating food industry wastewater in MBR

  • Ince, Mahir;Topaloglu, Alikemal;Ince, Elif
    • Membrane and Water Treatment
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    • v.9 no.1
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    • pp.33-42
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    • 2018
  • Microscopic examination of the activated sludge and morphological characterization of the flocs provides detailed information about the treatment process. The aim of this study is to investigate the morphological parameters of flocs obtained from a thermophilic jet loop membrane bioreactor (JLMBR) in different sludge retention times (SRTs), considering EPS and SMP concentration, hydrophobicity, zeta potential. The results showed that irregularity decreased with the increasing SRT. The compactness value was calculated to be less than 1 for all SRTs. However, the sludge had a more compact structure when the SRT increased. Zeta potential increased whereas hydrophobicity and floc size reduced, with increasing SRT. Furthermore, 2-D porosity calculated using the hole ratio was higher at greater SRTs. Hence, there was a significant correlation between the results obtained using the imaging technique and operation conditions of thermophilic JLMBR.

Effect of Structural and Morphological Changes on the Conductivity of Stretched PANI-DBSA/HIPS Film

  • Lee, Jong-Hyeok;Kim, Eun-Ok
    • Bulletin of the Korean Chemical Society
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    • v.32 no.8
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    • pp.2661-2665
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    • 2011
  • We studied the effect of structural and morphological changes on the conductivity of a stretched conducting polymer film. To improve the poor processability of polyaniline, we used dodecylbenzenesulfonic acid as both a surfactant and a dopant during emulsion polymerization, followed by blending with high-impact polystyrene. UV-Vis/NIR spectra were obtained to observe conformational changes, and SEM and AFM were used to investigate morphological changes. FT-IR dichroism was applied to determine the microscopic orientation, and XRD patterns were obtained for quantitative crystallinity analysis. The electrical conductivity (${\sigma}_{\parallel}/{\sigma}_{\perp}$) was measured as a function of draw ratio. We found a clear correlation between morphological changes and (${\sigma}_{\parallel}/{\sigma}_{\perp}$), especially at the stretching limit. The conductivity of the films can be modified according to the desired application by controlling their structure and morphology.

Codium fragile subsp. fragile (Suringar) Hariot in Tunisia: morphological data and status of knowledge

  • Cherif, Wafa;Ktari, Leila;Bour, Monia El;Boudabous, Abdellatif;Grignon-Dubois, Micheline
    • ALGAE
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    • v.31 no.2
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    • pp.129-136
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    • 2016
  • The Mediterranean Sea is currently facing dramatic changes and threats, including change in native species and accidental introductions. The introduced green alga Codium fragile subsp. fragile (Suringar) Hariot influences diversity and community structure in some parts of the world. This paper documents the distribution of this species in Tunisia and provides a morphological description of C. fragile subsp. fragile in Northern Tunisia. Results confirm the identity of Tunisian specimens as the invasive subspecies C. fragile subsp. fragile. This is the first morphological characterization of this subspecies in Tunisia.

Molecular analyses and reproductive structure to verify the generic relationships of Hypnea and Calliblepharis (Cystocloniaceae, Gigartinales), with proposal of C. saidana comb. nov.

  • Yang, Mi Yeon;Kim, Myung Sook
    • ALGAE
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    • v.32 no.2
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    • pp.87-100
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    • 2017
  • The genera Hypnea and Calliblepharis of the family Cystocloniaceae are discriminated by their female reproductive structure, especially in the formation of carposporangia and gonimoblasts. Hypnea saidana, once classified based on obsolete evidence, has not been studied phylogenetically using molecular analysis and detailed reproductive structure though it shares many morphologic features with the genus Calliblepharis. To provide better understanding of generic relationship of H. saidana with Hypnea and Calliblepharis, we carried out molecular analyses using the nuclear-encoded small subunit ribosomal DNA (SSU) and chloroplast-encoded large subunit of the RuBisCO (rbcL), and exact morphological observations focusing on the reproductive structures of wild specimens. Our molecular phylogeny showed that H. saidana is closely related to Calliblepharis, but distinct from the clade of Hypnea. Female reproductive structure of H. saidana characterized by upwardly developing chains of carposporangia, central reticulum of cell, and gonimoblast filaments not connected to the pericarp provides definite evidence to assign the taxonomic position of this species to Calliblepharis. Based on our combined molecular and morphological analyses, we have proposed Calliblepharis saidana comb. nov., expanding the distribution of Calliblepharis habitat from the eastern Atlantic South Africa, the northern Indian Ocean, Australasia, and Brazil to the western Pacific Ocean.

Morphological Characteristics of Pseudosclerotia of Grifola umbellata in In Vitro

  • Choi, Kyung-Dal;Lee, Kyung-Tae;Hur, Hyun;Hong, In-Pyo;Shim, Jae-Ouk;Lee, Youn-Su;Lee, Tae-Soo;Lee, Sang-Sun;Lee, Min-Woong
    • Mycobiology
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    • v.32 no.1
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    • pp.1-5
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    • 2004
  • The present study was carried out to investigate morphological characteristics of pseudosclerotia of Grifola umbellata formed by artificial cultures. Isolate G. umbellata DUM GUS-01 was obtained from sclerotium cultivated in field. The fungal isolate was cultured on PDYM broth, PDYMA(potato dextrose yeast malt agar) and oak sawdust media at $20^{\circ}C$ under the dark condition. G. umbellata DUM GUS-01 showed a volumetric increment of fungal lumps rather than mycelial growth. Particularly, G. umbellata DUM GUS-01 produced a large amount of melanin pigments in all culture treatments. The color of the fungal mass has been changed into grey gradually, and then formed melanized rind-like structure on its superficial part. The fungal structures which were covered with melanized rind-like layer were named as pseudosclerotia of G. umbellata. The pseudosclerotia of G. umbellata DUM GUS-01 formed a new white mycelial mass, which was swollen out of the melanized rind structure for its volumetric increment. When the pseudosclerotia were sectioned, their structure was discriminated from two structures such as a melanized rind-like structure layer formed by aggregation of aged mycelia and a white mycelial mass with high density. As results of scanning electron microscopic examination, the pseudosclerotia of G. umbellata DUM GUS-01 which were formed in in vitro conditions were similar to the sclerotia of G. umbellata cultivated in natural conditions except for the crystals formed in medula layer of natural sclerotia. Although size, solidity of rind structure and mycelial compactness of pseudosclerotia were more poor than those of natural sclerotia, the morphological structure and growth pattern of pseudosclerotia were very similar to those of natural sclerotia. Therefore, it is probable to induce pseudosclerotia to sclerotia of G. umbellata in in vitro conditions. Consequently, it seems that the induced pseudosclerotia can be used as inoculum sources to substitute natural sclerotia in field cultivation.