• Title/Summary/Keyword: accumulation phenomena

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A Study on Displacement Current Characteristics of DMPC Monolayer (II) (DMPC 인지질 단분자막의 변위전류 특성 연구 (II))

  • Song, Jin-Won;Lee, Kyung-Sup;Choi, Yong-Sung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.2
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    • pp.343-348
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    • 2007
  • The physical properties of DMPC monolayer were made for dielectric relaxation phenomena by the detection of the surface pressures and displacements current. Lipid thin films were deposited by accumulation and the current was measured after the electric bias across the manufactured MIM device. It is found that the phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area. When electric bias is applied across the manufactured MIM device by the deposition condition of phospolipid mono-layer, it wasn't breakdown when the higher electric field to impress by increase of deposition layers.

Interfacial Effects in Filled and Reinforced Polymeric Composites

  • Xie, Hengkun
    • Electrical & Electronic Materials
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    • v.11 no.10
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    • pp.24-31
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    • 1998
  • Interfacial effect in polymetric composites have been studied extensively. This report deals mainly with the effects of interfacial space charge and interface structure. A model for the dynamic process of interfacial space charge accumulation is proposed. The new model might interpret some interface phenomena which is difficult to be explained in terms of traditional Maxwell-Wagner theory. An interface structure is also presented, by which the importance of surface treatment of glass Fiber for improving the properties of FRP could be well understood.

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Effects of Dimethipin on the Senescence of Excised Barley First Leaves (Dimethipin이 절단한 보리 제 1엽의 노쇠에 미치는 영향)

  • 전방욱
    • Journal of Plant Biology
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    • v.33 no.1
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    • pp.25-30
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    • 1990
  • Effects of dimethipin on the senescence of excised barley first leaves were investigated. Dimethipin markedly inhibited chlorophyll and protein loss and reduced peroxidase activity relevant to senescence phenomena in th excised leaves. Dimethipin decreased hydrogen peroxide content, later malondialdehyde content, and increased the activities of superoxide dismutase and catalase. The antisenescence effects of dimethipin may result from the stabilization of membrane structure through inhibiting the peroxidation of unsaturated lipid and the accumulation of free radicals during senescence.

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A Semiotic Study on the Formation Process of Korean Folk-Belief (한국 속신의 형성과정에 대한 기호학적 고찰)

  • Kim, Kyung-Seop;Kim, Eun-Joo
    • The Journal of the Convergence on Culture Technology
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    • v.4 no.3
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    • pp.171-178
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    • 2018
  • Man is confronted with a lot of unknowable phenomena in his life. With the passage of time, man has interpreted the world by the accumulation of experience and development of thought. In the early days of the civilization when all the phenomena was not explained in a scientific way, man was dependent of the psycho-cultural interpretation by the accumulation of experience. Folk-Belief is one of the psycho-cultural interpretation about the nature. If Folk-Belief is paraphrased in a semiotic way, it is as follows : 'the traditional expression which believes that one or several sign and condition show one or several effects.' In this respect, Folk-Belief is the interpretation about the nature, man and society, as it were, the world. Folk-Belief is folkloristic semiotics. This article intends to clarify the process of Folk-Belief formation process. To investigate the Folk-Belief formation process, this article regards Folk-Belief as an interpretant which is the term from the semiotic theory of C. S. Peirce. Peirce explains the incessant semiosis that sign brings forth sign through the trichotomy relation among sign - object - interpretant. Folk-Belief is explained by the general characteristics of interpretant of Peirce when we regard Folk-Belief as an interpretant. By Peirce, Folk-Belief is 'something which believes that human mind represents something about some phenomena' The category of 'some phenomena' is included in a range of semiotics, we can look into Folk-Belief in a semiotic way.

Theoretical analysis of quantification of drought frequency inflow series via K-water cumulative difference method (누가차분법을 통한 가뭄 빈도유입량 산정에 관한 이론적 고찰)

  • Kim, Jiheun;Lee, Jae Hwang;Kim, Young-Oh
    • Journal of Korea Water Resources Association
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    • v.55 no.9
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    • pp.701-705
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    • 2022
  • Reliable drought inflow scenarios are required to plan reservoirs in response to the present severe drought-like conditions. However, the previously developed method for generating drought inflows, the K-water cumulative difference method (KCM), is considered inadequate owing to its potential for negative inflow, reversal phenomena, and overestimation. Nevertheless, the occurrence of these aspects has not been theoretically analyzed. Hence, this study employed the quantile function and frequency factor for log-normal and Gumbel distributions to quantify the contributing factors of these limitations. Consequently, it was found that the negative inflows are generated when the difference in the location parameters, during the accumulation process, exceeds that of the scale parameters. In addition, as the standard deviation decrease during the accumulation process, the reversal phenomena, and inflated values prevailed.

Segregation Phenomenon of As-Cast and Heat Treatment Microstructures in Investment Casting of IN738LC Superalloy (IN738LC 초내열합금 정밀 주조의 주조 및 열처리 미세조직에 구성되는 성분 편석 현상)

  • Choe, Byung Hak;Han, Sung Hee;Kim, Dae Hyun;Ahn, Jong Kee;Lee, Jae Hyun
    • Korean Journal of Materials Research
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    • v.31 no.7
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    • pp.409-419
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    • 2021
  • The effect of solidification rate on micro-segregation in investment casting of IN738LC superalloy was studied. In Ni-based superalloys, the micro-segregation of solute atoms is formed due to limited diffusion during cast and solidification. The microstructure of cast Ni-based superalloys is largely divided into dendrite core of initial solidification and interdendrite of final solidification. In particular, mosaic shaped eutectic γ/γ' and carbides are formed in the interdendrite of the final solidification region in some cases. The micro-segregation phenomena formed in regions of dendrite core and interdendrite including eutectic γ/γ' and carbides were analyzed using OM, SEM/EDS and micro Vickers hardness. As a result of analysis, the lack of (Cr, W) and the accumulation of Ti were measured in the eutectic γ/γ', and the accumulation of (Cr, Mo) and the lack of Ti were measured in the interdendrite between dendrite and eutectic. Carbides formed in interdendritic region were composed of (Ti, W, Mo, C). The segregation applied to each microstructure is mainly due to the formation of γ' with Ni3(Al,Ti) composition. The Ni accumulation accompanied by Cr depletion, and the Ti accumulated in the eutectic region as a γ' forming elements. The Mo tends to diffuse out from the dendrite core to the interdendrite, and the W diffuse out from the interdendrite to the dendrite core. Therefore, the accumulation of Mo in the interdendrite and the deficiency of W occur in the eutectic region located in the interdendrite. Heat treatment makes the degree of the micro-segregation decrease due to the diffusion during solid solution. This study could be applied to the heat treatment technology for the micro-segregation control in cast Ni-based superalloys.

A Study on the Shear Fatigue Analysis Model of Reinforced Concrete Beams (철근 콘크리트 보의 전단피로해석 모델 연구)

  • 오병환;홍경옥
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.10a
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    • pp.389-392
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    • 1999
  • Fatigue is a process of progressive permanent internal structural change in a material subjected to repeitive stresses. These change may be damaging and result in progressive growth of cracks and complete fracture if the stress repetitins are sufficiently large. For structural members subjected to cyclic loads, the continuous and irrecoverable damage processes are taking place. These processes are referred as the cumulative damage processes due to fatigue loading. Moreover, increased use of high strength concrete makes the fatigue problem more important because the cross-section and dead weight are reduced by using high strength concrete. The purpose of this study is to investigate the shear fatigue behavior of reinforced concrete beams according to shear reinforcement ratio and concrete compressive strength under repeated loadings. For this purpose, comprehensive static and fatigue tests of reinforced concrete beams were conducted. The major test variables for the fatigue teats are the concrete strength and the amount of shear reinforcements. The increase of deflections and steel strains according to load repetition has been plotted and analyzed to explore the damage accumulation phenomena of reinforced concrete beams. An analytical model for shear fatigue behavior has been introduced to analyze the damage accumulation under fatigue loads. The failure mode and fatigue lives have been also studied in the present study. The comparisons between analytical results and experimental data show good correlation.

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Molecular Control of Gene Co-suppression in Transgenic Soybean via Particle Bombardment

  • El-Shemy, Hany A.;Khalafalla, Mutasim M.;Fujita, Kounosuke;Ishimoto, Masao
    • BMB Reports
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    • v.39 no.1
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    • pp.61-67
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    • 2006
  • Molecular co-suppression phenomena are important to consider in transgene experiments. Embryogenic cells were obtained from immature cotyledons and engineered with two different gene constructs (pHV and pHVS) through particle bombardment. Both constructs contain a gene conferring resistance to hygromycin (hpt) as a selective marker and a modified glycinin (11S globulin) gene (V3-1) as a target. sGFP(S65T) as a reporter gene was, however, inserted into the flanking region of the V3-1 gene (pHVS). Fluorescence microscopic screening after the selection of hygromycin, identified clearly the expression of sGFP(S65T) in the transformed soybean embryos bombarded with the pHVS construct. Stable integration of the transgenes was confirmed by polymerase chain reaction (PCR) and Southern blot analysis. Seeds of transgenic plants obtained from the pHV construct frequently lacked an accumulation of endogenous glycinin, which is encoded by homologous genes to the target gene V3-1. Most of the transgenic plants expressing sGFP(S65T) showed highly accumulation of glycinin. The expression of sGFP(S65T) and V3-1 inherits into the next generations. sGFP(S65T) as a reporter gene may be useful to increase the transformation efficiency of transgenic soybean with avoiding gene co-suppression.

A Study on Modeling of Short-Circuliting Phenomena and Selection of Current Waveform for Reduction of Spatter in GMAW (가스 메탈 아크 용접에서 단락현상 모델링 및 스패터 감소를 위한 전류파형 선정에 관한 연구)

  • 황주호;문형순;나석주;한광수
    • Journal of Welding and Joining
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    • v.14 no.1
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    • pp.57-67
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    • 1996
  • With an expansion in automation of welding processes, emphasis has been shifted from other welding processes to the GMA welding. However, there is a problem with this process that the spatter occurs very frequently. In GMA welding, there are several types in the way of metal transfer from the electrode wire to the weld pool, which have a close relatonship with the spatter genetration. This study was concerned with the spatter occurring in the short-circuiting transfer. In welding with short-circuiting, the electromagnetic force formed by the welding current facilitatics the rupture of the metal bridge between the wire and workpiece and ensures the normal process of the welding process. However, the spatter can be genetrated from the droplet because of the upward magnetic force, when the droplet contacts with the weld pool. The passage of current through the bridge results in the accumulation of the thermal energy, which causes the bridge to explode in the final stage of short-circuiting, thus forming the spatter. Based on the above phenomena in conjunction with other experimental results published, the physical phenomenon related with the occurrence of spatter was modeled and the current waveform was investigated to reduce the spatter. Finally, the fuzzy rule based method was proposed to predict the time of short-circuiting and arcing in the metal transfer.

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Nail Art Design Applied Jean Dubuffet's Assemblage (Jean Dubuffet의 앗상블라주(Assemblage)를 응용한 네일아트 디자인)

  • Jang Ae-Ran
    • Journal of the Korean Society of Costume
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    • v.55 no.4 s.94
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    • pp.29-37
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    • 2005
  • Beauty Art is an act which makes a face beautiful using various methods such as permanent, manicure and make-up. Recently, Beauty Art is recognized as the personal culture expressing the value of beauty and spirit. Therefore, there are growing interests in the comprehensive study of Beauty Art nor only from the beauty industries but also from academia, because Beauty Art is the high value-added field and Is recognized as a style of the dress. The purpose of this study is to open a new view to understand the Nail Art as a fold of experimental plastic art. The arctic expression is added to Beauty Art to develop it from the routine technique of the make-up and hairstyling to creative art. Assemblage is adopted to provide Beauty Art with fine harmonious expression which develop Nail Art into interesting and unique art area. Assemblage meaning compounding or collection is a technique through which three-dimension is added to two-dimension paintings, and which is an expression of an art work by recollection of miscellaneous articles or waste materials. Assemblage is a term which Jean Dubuffet coioned first in order to differentiate collage used by Picaso or Braque. Here, I present Nail Art Designs which applied Jean Dubuffet's works focusing on Automaticity and Happenstantial phenomena of materials, Materialization, and Directness. These features are characteristics of Assemblage which basic frameworks are fantastic collection, accumulation, constructive collection, and object collection.