• Title/Summary/Keyword: chain formation

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Dielectrophoretic Alignment and Pearl Chain Formation of Single-Walled Carbon Nanotubes in Deuterium Oxide Solution

  • Lee, Dong Su;Park, Yung Woo
    • Carbon letters
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    • v.13 no.4
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    • pp.248-253
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    • 2012
  • Dielectrophoretic filtering and alignment of single-walled carbon nanotubes (SWCNTs) were tested using deuterium oxide as a solvent. A solution of deuterium oxide-SWCNTs was dropped on top of a silicon chip and an ac electric field was applied between pre-defined electrodes. Deuterium oxide was found to be a better solvent than hydrogen oxide for the dielectrophoresis process with higher efficiency of filtering. This was demonstrated by comparing Raman spectra measured on the initial solution with those measured on the filtered solution. We found that the aligned nanotubes along the electric field were not deposited on the substrate but suspended in solution, forming chain-like structures along the field lines. This so-called pearl chain formation of CNTs was verified by electrical measurements through the aligned tubes. The solution was frozen in liquid nitrogen prior to the electrical measurements to maintain the chain formation. The current-voltage characteristics for the sample demonstrate the existence of conduction channels in the solution, which are associated with the SWCNT chain structures.

Optimal Supply Chain Formation Using Buyer Agent Negotiation in SET Model based Make-To-Order (최적 공급사슬망 구성을 위한 구매자 에이전트 협상방법론 개발)

  • Kim, Hyeon-Su;Jo, Jae-Hyeong;Choe, Hyeong-Rim;Hong, Sun-Gu;Son, Jeong-Ha
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2005.11a
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    • pp.461-470
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    • 2005
  • A dynamic supply chain that is composed of many different companies with different rent roles and interests allows free joining and secession. Buyers place orders simultaneously and manufacturers should compete each other for the orders. The purpose of our paper is how to find the optimal formation of supply chain ill a global viewpoint while allowing each member company to pursue his local goal The dynamic nature of supply chain formation causes the variation of cost depending on how many orders a manufacturer would accept. We propose a multi-agent based negotiation protocol that efficiently leads to the formation of optimal supply chain without giving up maximization of the individual profit in multi-agent environment of the make-to-order industry. The goal of the negotiation is to form a supply chain to minimize the overall sum of manufacturers' manufacturing cost, and earliness cost and tardiness cost based on SET model. We compare the negotiation protocol with Branch & Bound method. Finally, the validity and performance of buyer's negotiation has been tested experimentally.

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Thermal plasticity of growth and chain formation of the dinoflagellates Alexandrium affine and Alexandrium pacificum with respect to ocean acidification

  • Lee, Chung Hyeon;Min, Juhee;Lee, Hyun-Gwan;Kim, Kwang Young
    • ALGAE
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    • v.36 no.4
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    • pp.285-298
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    • 2021
  • The amount of CO2 absorbed by the oceans continues to rise, resulting in further acidification, altering some functional traits of phytoplankton. To understand the effect of elevated partial pressures of CO2 (pCO2) on functional traits of dinoflagellates Alexandrium affine and A. pacificum, the cardinal temperatures and chain formation extent were examined under two pCO2 (400 and 1,000 µatm) over the range of temperature expected to be associated with growth. The growth rate and chain formation extent of A. affine increased with higher pCO2, showing significant changes in cardinal temperatures and a substantial increase in middle chain-length (4-8 cells) fractionation under elevated pCO2 condition. By contrast, there were no significant differences in specific growth rate and any chain-length fractionation of A. pacificum between ambient and elevated pCO2 conditions. The observed interspecies variation in the functional traits may reflect differences in ability of species to respond to environmental change with plasticity. Moreover, it allows us to understand the shifting biogeography of marine phytoplankton and predict their phenology in the Korea Strait.

Characteristics of chain-forming cells in Gyrodinium impudicum using fluorescent ConA

  • Park, Eun-Ju;Kim, Gwang-Hoon;Cho, Yong-Chul;Cho, Eun-Seob
    • Journal of the korean society of oceanography
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    • v.34 no.4
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    • pp.214-219
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    • 1999
  • Cells of the dinoflagellate Gyrodinium impudicum form characteristic chains, which are associated with sugar accumulated on the cell surface. To resolve the relationship between chain-formation and cell surface sugar accumulation, confocal microscopy was used to observe sugar accumulation points in the vegetative cells and long chain-forming cells of G. impudicum cells treated with fluorescent-tagged ConA. In the stationary and exponential phases, both vegetative cells and chain-forming cells were similar to each other in fluorescent intensity. There was no evidence that chain-forming cells had a specific location for sugar accumulation on the cell surface. Most of the cells formed 2-cell chains one day after inoculation, but longer chains consisting of 4-8 cells increased markedly in 4day and 8 day cultures. Gyrodinium impudicum chains usually consist of more than four cells, and chains of 8 or even 16 cells can be observed in mature cultures. Temperature played an importantrole in chain-formation of the cells, threshold temperature for the development of long chain-formation was 19 $^{\circ}$C.

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A Study on the Supply Chain Partnership for SCM - Focusing on Apparel Companies and Outsourcing Suppliers - (의류업계의 SCM을 위한 공급 사슬 파트너십에 관한 연구 - 의류 업체와 완제품 아웃소싱 공급 업체를 중심으로 -)

  • Rhee, Byung-Ju
    • The Research Journal of the Costume Culture
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    • v.16 no.1
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    • pp.181-203
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    • 2008
  • This study suggests a model to identify relationships between Supply Chain Partnership(SCP) and the performance of Supply Chain Management(SCM) based on apparel companies and outsourcing suppliers of finished products that are in a position of getting into Supply Chain Level on apparel industry. This research model is based on an integrated model including a relationship between relationship formation factors and partnership strengthening factors in SCP; and supply chain performance a result of that relationship. The formation factors of SCP affect emotional elements(trust, commitment) of strengthening factors, and they, in turn, impact the performance of a supply chain through behavioral elements(collaboration, information sharing)16 hypotheses were formulated to research the degree of impact of SCP on supply chain performance. Theoretical and empirical research was executed in parallel to achieve the objectives of this study. Empirical research involved a research methodology using surveys. Survey target audiences were limited to designers and merchandisers over five years of experience with apparel companies and outsourcing suppliers for finished products operating mainly in Korea. SPSS 12.0 for Windows and AMOS 5.0 were used for data and statistical analysis. Reviewing the result of research model and identification of each hypothesis, total 11 from 16 hypotheses set by this research were selected, 5 hypotheses were dropped, and 4 meaningful paths were added.

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Expression of a Carboxy-Terminal Deletion Mutant of Recombinant Tadpole H-Chain Ferritin in Escherichia coli

  • Lee, Mi-Young;Kim, Young-Taek;Kim, Kyung-Suk
    • BMB Reports
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    • v.29 no.5
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    • pp.411-416
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    • 1996
  • In order to study the role of the protein shell in both iron uptake and iron core formation of ferritin, we constructed a deletion mutant of the ferritin gene and expressed the mutant gene in Escherichia coli, This mutant was obtained by introducing an amber mutation at position Pro-157 and a deletion of the 19 amino acid residues at the carboxy-terminus of the recombinant tadpole H-chain ferritin. The deleted amino acids correspond to E-helix forming the hydrophobic channel in the protein. E. coli harboring the plasmid pTHP157, which contains the deleted gene, was grown at $23^{\circ}C$ in the presence of 0.1 mM IPTG, and the induced protein appeared to be partly soluble. Nondenaturing polyacrylamide gel electrophoresis showed that the expressed mutant H-chains coassemble into holoprotein, suggesting that E-helix is not necessary for assembly of the subunits as reported for human H-chain ferritin. Its ability in iron core formation was proven in an Fe staining gel, the result disagreeing with the observation that the hydrophobic channel is necessary for iron core formation in human H-chain ferritin.

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Comparison on Track Formation Range between TWS and Adaptive Tracking Using Markov Chain Analysis in a Radar System (레이더에서의 Markov Chain 분석을 이용한 TWS 방식과 Adaptive Tracking 방식의 추적 형성 거리 비교)

  • Ahn, Chang-Soo;Roh, Ji-Eun;Jang, Sung-Hoon;Kim, Seon-Joo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.5
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    • pp.574-580
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    • 2013
  • Compared with the TWS(Track While Scan) tracking that uses scan-to-scan correlation at search illuminations for targets track, a phased array radar can use adaptive tracking which assigns additional track illuminations and the track formation range can be improved as a result. In this paper, an adaptive tracking, the search and track illuminations of a target are synchronized such that the extra illuminations are evenly distributed between the search illuminations, is proposed. Markov chain and track formation range for the proposed adaptive tracking are shown with them for the conventional TWS. The simulation result shows that the proposed adaptive tracking has improved track formation range by 27.6 % compared with the conventional TWS tracking under same track confirmation criterion.

Effect of Variation in the Molecular Structure on the Miscibility of Modified Polystyrene/Polymethacrylate Blends (Modified Polystyrene/Polymethacrylate 블렌드의 상용성에 대한 분자구조 변화의 영향)

  • Koo, Chung-Wan;Kim, Hyung-Il;Kim, Byeong Cheol
    • Applied Chemistry for Engineering
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    • v.10 no.5
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    • pp.743-747
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    • 1999
  • The component polymer was modified to enable the formation of intermolecular hydrogen bonding in the immiscibile polystyrene(PS)/polymethacrylate(PMA) blends. The mole percentages of hydroxystyrene of the poly(styrene-co-4-hydroxystyrene) copolymer(modified polystyrene, MPS) were controlled to 7%, 10% and 18%, respectively. MPS was used with PMA to study the variation of the miscibility in blends. PMA which had such different length of side chain as methyl, butyl, hexyl and ethylhexyl, respectively, was selected to study the effect of side chain length on the formation of intermolecular hydrogen bonding. As the hydroxyl content of MPS increased, the formation of intermolecular hydrogen bonding increased. The length of side chain of PMA had enormous effect on the miscibility of blend as confirmed from the result of cloud point measurement. As the length of side chain increased, the formation and the strength of intermolecular hydrogen bonding decreased severely due to the steric effect and the increased chain mobility.

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Purification and Characterization of Recombinant Tadpole H-Chain Ferritin in Escherichia coli

  • Chang, So-Ran;Kim, Young-Taek;Kim, Kyung-Suk
    • BMB Reports
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    • v.28 no.3
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    • pp.238-242
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    • 1995
  • The tadpole H-ferritin produced in E. coli was purified and its molecular properties were investigated to obtain information about the contribution of the H-subunit in the reaction of iron core formation. All the expressed subunits were assembled into complete holoprotein in vitro, presumably 24-mer, and the protein was heat-stable. Electron microscopy revealed that the recombinant ferritin forms spherically and contains iron core. No difference was observed in the absorption spectrum of the expressed protein compared to that of the natural ferritin. The Ouchterlony double diffusion of the expressed protein showed that the H-chain ferritin shares an antigenic determinant with natural tadpole ferritin. Rabbit anti-horse spleen ferritin discriminated the H-ferritin from natural ferritin. The rate of ferritin formation by the recombinant H-chain apoferritin was determined to be higher than that shown by natural tadpole ferritin, which consists of H, M and L-subunits. This phenomenon may be caused by the absence of M and L-subunits in the recombinant H-chain apoferritin.

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A Design of the Semantic Web for Collaborative Agents in Supply Chain Formation (공급사슬구성에서 협력적 에이전트를 위한 시맨틱 웹 설계)

  • Kim, Hyun-Soo;Cho, Jae-Hyung;Choi, Hyung-Rim;Hong, Soon-Goo
    • The Journal of Information Systems
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    • v.13 no.2
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    • pp.135-153
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    • 2004
  • The formation of a supply chain should be approached with distributive viewpoint considering the dynamic nature of ordering environments. The purpose of this paper is to design a semantic web to support agent negotiation forming supply chains. With the view of a supply chain as composed of competitive agents which represent each member of supply chains with a local goal, a supply chain is formed through negotiation of price, due date choosing partners to contract. In the development of a negotiation method, we employ ontology and rules which are the basic techniques of the semantic web for supporting automated negotiations. Especially, a framework for a negotiation process is suggested and domain, processes and rules ontology are designed interrelatedly. With this modeling, a possibility of the semantic web based agent negotiation is suggested.

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