• Title/Summary/Keyword: Chain transfer

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A Study on the International Transfer of Retail Know-how: A Case of 7-Eleven (소매 노하우의 국제이전에 관한 연구 : 7-Eleven 사례를 중심으로)

  • Kim, Hyun-Chul
    • Journal of Distribution Research
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    • v.13 no.4
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    • pp.1-19
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    • 2008
  • This study investigated the international transfer of retail know-how via the prism of Learning Organizational Theory. As a case, 7-Eleven, a worldwide chain of convenience stores was examined. Its international transfer of retail know-how occurred when 7-Eleven, originally founded by Southland Corporation in Dallas, Texas, was introduced in Japan in 1973 in the form of 7-Eleven Japan. Our analysis shows that both strategic core learning and adaptive learning played a significant role during the international transfer of retail know-how. Our findings reveal the evidence of the following elements of strategic core learning such as the convenience store concept, the three principles of store management, the minimum profit guarantee system, and the margin-based royalty system. On the other hand, the retailing mix such as store type, store location, store size, and merchandising acted as the acting agents of adaptive learning. The hypothesis verification methods acted as the main methods for adaptive learning. Through the persistent adaptive learning, inimitable innovations could be brought forth. However, the elements of strategic core learning should provide the direction for the adaptive learning.

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Comparison to Dielectric Properties of LB Films for Length of Methylene Group (메틸렌기의 길이에 따른 LB막의 유전 특성 비교)

  • Kang, Ki-Ho;Kim, Do-Kyun;Choi, Yong-Sung;Chang, Jeong-Soo;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1843-1845
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    • 1999
  • We have investigated the dielectric characteristics of palmitic acid(PA), stearic acid (SA) and arachidic acid(AA) Langmuir-Blodgett(LB) films because these fatty acid systems have a same hydrophilic group and a different hydrophobic one (alkyl chain length). In this work. fatty acid systems were used as LB films and the status of the deposited films was confirmed by evaluating the transfer ratio. the UV absorption and the capacitance. Also, the dielectric characteristics such as the frequency-capacitance characteristics and the dielectric dispersion and absorption characteristics of PA, SA and AA through-plane were measured. The relative dielectric constants of PA, SA and AA LB films were about $2.6\sim4.6$, $2.4\sim4.1$ and $2.2\sim3.8$, respectively. That is, the relative dielectric constants were decreased in proportion to the chain length of methylene group. And, the dielectric dispersion and absorption of each fatty acid LB films have arisen from spontaneous polarization of dipole polarization in the range of $10^4\sim10^5[Hz]$.

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Developing XML Messaging System for Supply Chain Management (공급사슬관리를 위한 XML 메시징 시스템 개발)

  • 김용수;임종선;주경준;주경수
    • Journal of Internet Computing and Services
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    • v.3 no.5
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    • pp.1-8
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    • 2002
  • Because XML is a W3C standard and has characteristics like platform-independent, it has a critical role in e-commerce. Business rules and procedures should be standardized for efficient B2B integration, But a lot of companies are its own XML documents instead of standard document, Therefore many organizations try to make standards for e-commerce based on framework. Also, in case use supply chain administration system, because document transmit between corporation use on-line, need messaging system that can transfer XML message In this paper, XML messaging system is designed and implemented. Client requests service in XML and server returns response in XML in this system, So we con more easily and efficiently to exchange document between company this XML messaging system.

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Synthesis and Characterization of Low Molecular Weight Poly(methyl acrylate)-b-Polystyrene by a Combination of ATRP and Click Coupling Method

  • Hasneen, Aleya;Kim, Su-Jeong;Paik, Hyun-Jong
    • Macromolecular Research
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    • v.15 no.6
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    • pp.541-546
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    • 2007
  • The combination of atom transfer radical polymerization (ATRP) and click chemistry was employed for the efficient preparation of well-defined block copolymers. Bromo terminated poly(methyl acrylate) (pMA-Br) was prepared by an ATRP initiator, ethyl-2-bromoisobutyrate (EBiB). Subsequently, the bromine chain end of pMA-Br was converted to an azide group by simple nucleophilic substitution reaction. ${\alpha}-Alkyn-{\omega}-bromo-functionalized$ polystyrene was also synthesized by ATRP using the alkyn-functionalized initiator, propargyl-2-bromoisobutyrate (PgBiB). In both cases, the conversion was limited to a low level to ensure a high degree of chain end functionality. Then the coupling reaction between the azide end group in $pMA-N_3$ and alkyn-functionalized PgBiB-pSt was performed by Cu(I)catalysis. This coupling reaction was monitored by gel permeation chromatography (GPC). The synthesized block copolymer was characterized by FT-IR, $^1H-NMR$ spectroscopy and $^1H-^1H$ COSY correlation spectroscopy.

Preparation and Rheological Properties of Alkali-Soluble Associative Thickener (알칼리 용해성 회합 증점제의 합성 및 유성학적 물성에 관한 연구)

  • Seo, Eun-Hyun;Lee, Doug-Youn;Lee, Jong-Kil;Kim, Jung-Hyun
    • Applied Chemistry for Engineering
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    • v.8 no.4
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    • pp.673-678
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    • 1997
  • Associative acrylic thickeners were prepared by emulsion copolymerization using nonionic vinyl surfactant esters as an associative macromonomer and their rheological properties were investigated. The thickening efficiency was shown to depend on the chain length of therminal hydrophobe and degree of ethoxylation of VSE. increasing the content of VSE enhanced the efficiency of the resulting polymers as a thickener. It was attributed to the intermolecular association of terminal hydrophobes of associative thickener in aqueous solution. The chain transfer agent caused to reduce the molecular weight of associative thickener, resulted in decrease of thickening efficiency.

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Qualitative Analyses of Porypyrrole-Glucose Oxidase Enzyme Electrode for Immobilization (Polypyrrole-Glucose Oxidase 효소전극에 대한 효소 고정화의 정성적 평가)

  • Kim, Hyun-Cheol;Gu, Hal-Bon;SaGong, Geon
    • Proceedings of the KIEE Conference
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    • 1999.11d
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    • pp.984-986
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    • 1999
  • In the case of immobilizing of glucose oxidase in organic polymer using electrosynthesis, the glucose oxidase obstructs charge transfer and mass transport during the film growth. This may lead to short chained polymer and make charge-coupling weak between the glucose oxidase and the backbone of the polymer. That is mainly due to insulating property and net chain of the glucose oxidase. Such being the case, it is useless to increase in amount of glucose oxidase more than reasonable in the synthetic solution. We establish by means of qualitative analysis that amount of immobilized glucose oxidase can be improved by adding a hole ethyl alcohol in the synthetic solution. As ethyl alcohol was added by 0.1mol $dm^{-3}$ in the synthetic solution, the faradic impedance of resultant electrode was increased about five times as much as the case of ethyl alcohol free in the solution, and mass transport was limited more than over. That is due to insulating property and net chain of the glucose oxidase. Moreover, in ultraviolet spectra of the synthetic solution, the adsorption peak at 285nm corresponding to glucose oxidase was decreased. It suggests increase in amount of immobilized glucose oxidase.

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THERMAL POLYMERIZATION OF 2-HYDROXYETHYL METHACRYLATE WITH PHENYLSILANS (PHENYLSILANS와 2-HYDROXYETHYL METHACRYLATE의 열중합)

  • Sung, A Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.5 no.2
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    • pp.87-90
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    • 2000
  • Poly(HEMA)s have been used as the optometric material for the preparation of soft contact lens. The bulk thermal polymerization of 2-hydroxyethyl methacrylate (HEMA) with various hydrosilanes such as $phSiH_3$, $phMeSiH_2$, and $ph2SiH_2$ were performed to produce poly(HEMA)s containing phenylsilyl end moeity. It was found for thermal polymerization that while the polymerization yield and polymer molcular weights decreased as the relative phenylsilane concentration increases, the TGA residue yields and the relative intensities of SiH IR stretching bands increased as the relative hydrosilane concentration increases over HEMA. The polymerization yield, molecular weight, and TGA residue for the thermal polymerization were higher than those for the photo polymerization. Thus, the hydrosilanes significantly influence on the polymerization as both chain-initiation and chain-transfer agents.

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Full-Duplex Operations in Wireless Powered Communication Networks

  • Ju, Hyungsik;Lee, Yuro;Kim, Tae-Joong
    • ETRI Journal
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    • v.39 no.6
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    • pp.794-802
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    • 2017
  • In this paper, a wireless powered communication network (WPCN) consisting of a hybrid access point (H-AP) and multiple user equipment (UE), all of which operate in full-duplex (FD), is described. We first propose a transceiver structure that enables FD operation of each UE to simultaneously receive energy in the downlink (DL) and transmit information in the uplink (UL). We then provide an energy usage model in the proposed UE transceiver that accounts for the energy leakage from the transmit chain to the receive chain. It is shown that the throughput of an FD WPCN using the proposed FD UE (FD-WPCN-FD) can be maximized by optimal allocation of the UL transmission time to the UE by solving a convex optimization problem. Simulation results reveal that the use of the proposed FD UE efficiently improves the throughput of a WPCN with a practical self-interference cancellation capability at the H-AP. Compared to the WPCN with FD H-AP and half-duplex (HD) UE, FD-WPCN-FD achieved an 18% throughput gain. In addition, the throughput of FD-WPCN-FD was shown to be 25% greater than that of WPCN in which an H-AP and UE operated in HD.

Amphiphilic Norbornene-Based Diblock Copolymers Containing Polyhedral Oligomeric Silsesquioxane Prepared by Living Ring Opening Metathesis Polymerization

  • Park, Su-Dong;Xu, Wentao;Chung, Chan-Hong;Kwon, Young-Hwan
    • Macromolecular Research
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    • v.16 no.2
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    • pp.155-162
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    • 2008
  • We report the successful synthesis of poly(NBECOOH-b-NBEPOSS) copolymers, taking advantage of the sequential, living ring opening metathesis polymerization of NBETMS and NBEPOSS using the $RuCl_2(=CHPh)(PCY_3)_2$/$CH_2Cl_2$/$20^{\circ}C$ system, followed by the hydrolysis of trimethylsilyl groups in poly(NBETMS-b-NBEPOSS) copolymers. The living behavior of ROMP of NBETMS was first investigated using two diagnostic plots, a first order kinetic plot and a $\bar{M}_n$ vs. conversion plot. The plots confirmed that no termination and chain transfer reaction had occurred during polymerization. Poly(NBECOOH-b-NBEPOSS) copolymers were prepared using the sequential monomer addition of NBEPOSS to living poly(NBETMS) chain ends, followed by the hydrolysis of trimethylsilyl groups in the poly(NBETMS-b-NBEPOSS) copolymers. The high structural integrity of poly(NBE-COOH-b-NBEPOSS) copolymers was confirmed by $^1H$-NMR, $^{13}C$-NMR spcctroscopy and GPC.

Studies on the Graft Copolymerization of Glycidylmethacrylate to Chloroprene Rubber and the Adhesive Nature of the Copolymer (클로로프렌고무와 글리시딜메타아크릴과의 그라프트 공중합 반응과 그 공중합물의 접착능에 관한 연구)

  • Sohn, Jin-Eon;Choe, Byong-Kwon
    • Elastomers and Composites
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    • v.11 no.1
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    • pp.54-62
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    • 1976
  • It has been studied the graft copolymerization of glycidyl-methacrylate monomer containing two functional groups (vinyl- & epoxyl-) to chloroprene rubber. The reaction occured in the manner of chain transfer mechanism was carried out by means of solution polymerization in toluene in the presence of benzoyl peroxide as the radical initiator. The graft copolymer obtained from this work was analyzed by using IR spectrum, and the physical properties of the polymer such as the thermal behavior were also studied according to TG-DTA methods, and the potency of adhesiveness for the purpose of commercial application was investigated. Experimental results for the graft copolymerization are summarized as follows. 1) A small amount of initiator (0.5%) and 50% of monomer showed the best result for the grafting of monomer to the polymer chain of rubber while the 15% of rubber solution was found to be most suitable to raise either for the grafting ratio or the polymerization ratio. 2) Optimum temperature for better yield of graft copolymer was proved to he at $75^{\circ}C\sim80^{\circ}C$ while those of reaction time was to be $1\sim2$ hours.

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