• Title/Summary/Keyword: Self-aggregate

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Studies on the Micelle Formation of Nonionic Surfactant(1) -1NMR Self-Diffusion and Proton Relaxation of Polyoxyethylene Alkyl Ether- (계면활성제 수용액의 미셀형성(제1보) - Polyoxyethylene Alkyl Ether의 자기확산과 프로톤 이완 -)

  • Choi, Seung-Ok;Jeong, Hwan-Kyeong;Lee, Jin-Hee;Nam, Ki-Dae
    • Applied Chemistry for Engineering
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    • v.9 no.6
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    • pp.822-828
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    • 1998
  • Binary system of water and polyoxyethylene dodecyl ether, $C_{12}H_{25}(OCH_2CH_2)nOH$, have been studied by $^1H$ NMR techniques. For n=5($C_{12}EO_5$) and n=8($C_{12}EO_8$), the self-diffusion coefficients of nonionic surfactants in the isotropic phase($L_1$) have been measured by using pulsed field gradient technique for a range of temperature and concentrations. In addition the line widths of the different proton signals have been monitored, and samples of some liquid crystalline characteristic were also studied. Dramatic Broadening of the methylene signals of the alkyl($C_{12}H_{25}$) chain is observed as the hexagonal liquid crystalline phase is approached in the $C_{12}EO_5-$water system, while only small broadening is observed in the $C_{12}EO_8-$water system. It was shown that there was a growth of $C_{12}EO_5$ micelles to rods with increasing concentrations, while the $C_{12}EO_8-$ micelles at low temperature remain small in the concentration range. The self-diffusion coefficients of the surfactants decrease rapidly with increasing concentration until a minimum is reached after which there is slow increase. The location of the minimum point occurs at lower concentrations the temperature is close to the cloud point, where the system separate into two isotropic phase. In the line width studies, broadening is found at a certain temperature interval when the concentration is increased in the $C_{12}EO_5$ system. The results indicate that the surfactant aggregates grow in size at the cloud point is approached. The aggregates seem to be flexible and probably not to be of a definite shape close to the cloud point. In the $C_{12}EO_8$ system, the micelles are much less affected by an increase in temperature and micellar growth can't be unambiguously established. The methylene signals of the ethylene oxide moieties consistantly show narrower $^1H$ signals, showing that in the aggregates they are less ordered than the chain methylenes. The various changes in aggregate size and shape are correlated with the stability ranges of the isotropic and liquid crystalline phases according to phase diagrams from the literature. Both aggregate size and phase structure are in qualitative agreement with concentration based on the effective shape of the molecules at different temperature and concentration.

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ACTIFELD에 근거한 증평 장소마케팅의 전략적 의사결정

  • Hong, Seong-Ho;Kim, Mi-Seong;Kim, Bo-Gyeong;Kim, Chong-Hoe;Lee, Man-Hyeong
    • Proceedings of the Korean System Dynamics Society
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    • 2007.06a
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    • pp.93-111
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    • 2007
  • Even though place-marketingstrategies geared towards upgrading regional competitiveness have been brought to the forefront, due attention has not given to how to set up practical and viable strategies. Based on Geoff Coyle's ACTIFELD method, this study aims at formulating a series of implementation strategies of Jeungpyeong Place-Marketing. As the ACTIFELD technique contains intrinsic devices which would facilitate structural and systematic approach, it can easily encompass both qualitative and quantitative factors in reinterpreting complicated social phenomena and providing feasible alternatives. Furthermore, the study carries out additional public opinion surveys and expert brainstorming methods, as specific means to overcome relative weak points within the proposed ACTIFELD approach. The followings are major research findings. Firstly, in terms of maximizing existing strategies, Jeungpyeong should develop commercial items focused on Korean Ginseng and its byproducts. Secondly, among various festivals, Jeungpyeong should devise concrete processes to concurrently concentrate its support on Pork (Samgyupsal) and Korean Ginseng Festivals. Thirdly, as the majority of Jeungpyeong people prefers both do-it-your-self and traditional types, Jeungpyeong should prepare appropriate governance systems to deal with these issues. Fourthly, in order to contribute regional vitality, Jeungpyeong should strengthen public relation activities including guest-staying facilities. Lastly, Jeungpyeong should constantly improve the aggregate value of County Identity (CI)-based brands and it should also pursue production and public relation strategies actively applying the elderly.

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Adhesive Strength in Tension of High Volume PAE-Modified Cement Mortar with High Flowability for Floor Finishing

  • Do, Jeong-Yun;Soh, Yang-Seob
    • Journal of the Korea Concrete Institute
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    • v.15 no.5
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    • pp.739-746
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    • 2003
  • Various researches on the application of polymer dispersions to the cement mortar and concrete have been carried out in many countries like America, Japan and Germany and so on due to their high performance and good modification effect. PAE of polymer dispersion widely used in situ was employed that the high flowability may be induced in the cement mortar. In order to investigate the modification of cement mortar with high flowability by PAE and fracture mode of adhesive strength properties in tension of that, experimental parameters were set as PAE solid-cement ratio(P/C) and cement: fine aggregate(C:F) and the experiments such as unit weight, flow, consistency change, crack resistance and segregation that inform on the general properties have been done. Adhesion in tension is measured with a view to comprehending the properties and fracture mode in tensile load. Consistency change of cement mortar modified by PAE did grow better as the ratio of PAE solid-cement increased and was much superior to that of resin based flooring such as polyurethane and epoxy which recorded the loss of consistency in 90 min. after mixing. Adhesive strength in tension increased with continuity during curing period and showed the maximum in case of C:F=1:1 and P/C=20%.

Prediction model of resistivity and compressive strength of waste LCD glass concrete

  • Wang, Chien-Chih
    • Computers and Concrete
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    • v.19 no.5
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    • pp.467-475
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    • 2017
  • The purpose of this study is to establish a prediction model for the electrical resistivity ($E_r$) of self-consolidating concrete by using waste LCD (liquid crystal display) glass as part of the fine aggregate and then, to analyze the results obtained from a series of laboratory tests. A hyperbolic function is used to perform nonlinear multivariate regression analysis of the electrical resistivity prediction model, with parameters such as water-binder ratio (w/b), curing age (t) and waste glass content (G). Furthermore, the relationship of compressive strength and electrical resistivity of waste LCD glass concrete is also found by a logarithm function, while compressive strength is evaluated by the electrical resistivity of non-destructive testing (NDT). According to relative regression analysis, the electrical resistivity and compressive strength prediction models are developed, and the results show that a good agreement is obtained using the proposed prediction models. From the comparison between the predicted analysis values and test results, the MAPE value of electrical resistivity is 17.0-18.2% and less than 20%, the MAPE value of compressive strength evaluated by $E_r$ is 5.9-10.6% and nearly less than 10%. Therefore, the prediction models established in this study have good predictive ability for electrical resistivity and compressive strength of waste LCD glass concrete. However, further study is needed in regard to applying the proposed prediction models to other ranges of mixture parameters.

Bio-functionalized Gold Nanoparticles for Surface-Plasmon- Absorption-Based Protein Detection

  • Kim, Wan-Joong;Choi, Soo-Hee;Rho, Young-S.;Yoo, Dong-Jin
    • Bulletin of the Korean Chemical Society
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    • v.32 no.12
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    • pp.4171-4175
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    • 2011
  • Bio-functionalized gold nanoparticles (AuNPs), which bio-specifically interact with biotin-(strept)avidin, were investigated in this study. AuNPs were functionalized with a synthetically-provided biotin-linked thiol (BLT), which was synthesized by amidation of the active ester of biotin with 2-mercaptoethylamine. The BLT-attached AuNP was bio-specific for streptavidin, making it potentially useful for biosensor applications. To test the bio-specific interactions, the colors, absorption spectra and TEM images were investigated for proteins such as streptavidin, cytochrome C, myoglobin and hemoglobin. The colors and absorption spectra changed when streptavidin was added to the BLT-attached AuNP solution. However, the color and spectra did not change when the other proteins were added to the same solution. These results show that the AuNPs provided a colloidal solution with excellent stability and highly selective absorption characteristics for streptavidin as a target molecule. Proteins were also screened in order to identify a general strategy for the use of optical biosensing proteins based on AuNPs. In addition, TEM images confirmed that streptavidin led the BLT-attached AuNPs to aggregate or precipitate.

Self-organized Spectrum Access in Small-cell Networks with Dynamic Loads

  • Wu, Ducheng;Wu, Qihui;Xu, Yuhua
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.5
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    • pp.1976-1997
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    • 2016
  • This paper investigates the problem of co-tier interference mitigation for dynamic small- cell networks, in which the load of each small-cell varies with the number of active associated small-cell users (SUs). Due to the fact that most small-cell base stations (SBSs) are deployed in an ad-hoc manner, the problem of reducing co-tier interference caused by dynamic loads in a distributed fashion is quite challenging. First, we propose a new distributed channel allocation method for small-cells with dynamic loads and define a dynamic interference graph. Based on this approach, we formulate the problem as a dynamic interference graph game and prove that the game is a potential game and has at least one pure strategy Nash equilibrium (NE) point. Moreover, we show that the best pure strategy NE point minimizes the expectation of the aggregate dynamic co-tier interference in the small-cell network. A distributed dynamic learning algorithm is then designed to achieve NE of the game, in which each SBS is unaware of the probability distributions of its own and other SBSs' dynamic loads. Simulation results show that the proposed approach can mitigate dynamic co-tier interference effectively and significantly outperform random channel selection.

A New Design Approach for Optimization of GA-based SOPNN (GA 기반 자기구성 다항식 뉴럴 네트워크의 최적화를 위한 새로운 설계 방법)

  • Park, Ho-Sung;Park, Byoung-Jun;Park, Keon-Jun;Oh, Sung-Kwun
    • Proceedings of the KIEE Conference
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    • 2003.07d
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    • pp.2627-2629
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    • 2003
  • In this paper, we propose a new architecture of Genetic Algorithms(GAs)-based Self-Organizing Polynomial Neural Networks(SOPNN). The conventional SOPNN is based on the extended Group Method of Data Handling(GMDH) method and utilized the polynomial order (viz. linear, quadratic, and modified quadratic) as well as the number of node inputs fixed (selected in advance by designer) at Polynomial Neurons (or nodes) located in each layer through a growth process of the network. Moreover it does not guarantee that the SOPNN generated through learning has the optimal network architecture. But the proposed GA-based SOPNN enable the architecture to be a structurally more optimized networks, and to be much more flexible and preferable neural network than the conventional SOPNN. An aggregate performance index with a weighting factor is proposed in order to achieve a sound balance between approximation and generalization (predictive) abilities of the model. To evaluate the performance of the GA-based SOPNN, the model is experimented with using nonlinear system data.

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Theoretical Inquiry for the Study on Beauty Aesthetics - Centered on the hairstyle -

  • Kim, Seong-Nam;Jung, Hyun-Jin
    • Journal of Fashion Business
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    • v.12 no.3
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    • pp.16-30
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    • 2008
  • The purpose of this study is to inquire into the necessity and problem of the study on beauty aesthetics, and the direction and method of its study theoretically by applying the concept of aesthetics to the beauty art as an attempt to build up aesthetic concepts of beauty art. As results of inquiry, the study on beauty aesthetics is essential for the adaptation to demands for the creativity of beauty art. As for problem of study on beauty aesthetics, it is necessary to conduct an aggregate study at various angles since the aesthetic value of beauty art (hairstyle) is realized by interaction of the social cultural value or practical value and pure artistic value, and the unique cosmetic beauty of any era or nation group individual is created on the basis of hair designers and individual spirit, emotion and taste, etc. and its perceptual aesthetic enjoyment is accomplished variously. As for the direction and method of study on beauty aesthetics, the quest with abstract speculative self-examination into the beauty having its subjective meaning must be accomplished. This thesis would like to contribute to the building up of beauty industry field as beauty arts based on the aesthetics by successive coming forward of personnel for beauty who combine the aesthetic abilities meeting the diversified requirements of modern society and by improving the recognition of persons recognizing the beauty industry field as a technical field only.

A Comparison Analysis of the Labor Efficiency between Quality-Adjusted Labor and Quality-Unadjusted Labor in Jeju Mandarin Production -Based on the Difference in Market Wages- (농업 노동의 질적 차이를 반영한 감귤 생산 노동투입 효율성 비교 분석 -시장 임금차이를 기준으로-)

  • Lee, Bong-Sil;Yu, Young-bong
    • Journal of Agricultural Extension & Community Development
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    • v.28 no.3
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    • pp.153-165
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    • 2021
  • This study aims to analyze the difference in production elasticity based on the types of agricultural labor input regarding its qualitative difference in Jeju mandarin production. To estimate the production function of qualityadjusted labor, we have set up a Quality-Adjusted Index based on the market wage of the agricultural field. We have conducted a multiple regression analysis of the newly estimated labor inputs using the Ordinary Least Squares regression. Results show that the production efficiency of aggregate total labor hours (quality-unadjusted labor input) is overestimated compared to quality-adjusted labor with qualitative labor homogeneity. Moreover, by analyzing household labor and employment labor, we have observed that the marginal productivity of household labor exceeds that of employment labor. In conclusion, this study verifies that securing labor input homogeneity is crucial for analyzing agricultural labor hours' economic efficiency accurately.

Biofilm Signaling, Composition and Regulation in Burkholderia pseudomallei

  • Pravin Kumran Nyanasegran;Sheila Nathan;Mohd Firdaus-Raih;Nor Azlan Nor Muhammad;Chyan Leong Ng
    • Journal of Microbiology and Biotechnology
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    • v.33 no.1
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    • pp.15-27
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    • 2023
  • The incidence of melioidosis cases caused by the gram-negative pathogen Burkholderia pseudomallei (BP) is seeing an increasing trend that has spread beyond its previously known endemic regions. Biofilms produced by BP have been associated with antimicrobial therapy limitation and relapse melioidosis, thus making it urgently necessary to understand the mechanisms of biofilm formation and their role in BP biology. Microbial cells aggregate and enclose within a self-produced matrix of extracellular polymeric substances (EPSs) to form biofilm. The transition mechanism of bacterial cells from planktonic state to initiate biofilm formation, which involves the formation of surface attachment microcolonies and the maturation of the biofilm matrix, is a dynamic and complex process. Despite the emerging findings on the biofilm formation process, systemic knowledge on the molecular mechanisms of biofilm formation in BP remains fractured. This review provides insights into the signaling systems, matrix composition, and the biosynthesis regulation of EPSs (exopolysaccharide, eDNA and proteins) that facilitate the formation of biofilms in order to present an overview of our current knowledge and the questions that remain regarding BP biofilms.