• Title/Summary/Keyword: PP&E

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A Study of Size and Frictional Effects on the Evolution of Melting Part I : Batch Mixer (입자크기와 마찰효과가 용융 과정에 미치는 영향 Part I : 회분식 혼련기)

  • Kim, Dong-Sung;Park, Yung-Jin;Lee, Bong-Kyu;Kim, Hyung-Su;Lee, Jae-Wook
    • The Korean Journal of Rheology
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    • v.11 no.1
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    • pp.44-49
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    • 1999
  • Effects of particulate size and frictional characteristics were examined on the melting behavior of PP (polypropylene) in a batch mixer. Powder and pellet types of PP were used and each component was blended with PE (polyethylene) wax and clay, respectively. It was observed that small size particulates, i.e. powder systems exhibit accelerated melting behavior; and it was also found that the abrasive additive acts as an effective agent for fast melting of PP powder. Retardation of melting due to the reduced friction was observed in PP pellet/PE wax blends, while melting rate of PP powder was increased by addition of PE wax.

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City Diplomacy: Current Trends and Future Prospects (1st edition), edited by Sohaela Amiri and Efe Sevin, Palgrave Macmillan, 2020, 389 pp., €85.59 (eBook), ISBN 9783030456146. Urban Diplomacy: A Cosmopolitan Outlook, by Juan Luis Manfredi-Sánchez, Bill Research Perspectives in Diplomacy and Foreign Policy, 2021, 96 pp., $108.54 (Paperback), ISBN 9004472177. City Diplomacy: From City-States to Global Cities, by Raffaele Marchetti, University of Michigan Press, 2021, 144 pp., €66.14 (Hardcover), ISBN 9780472055036.

Synthesis of Multifunctional Polypropylene-g-(acrylic acid/styrene) Fibrous Ion Exchanger by Electron Beam and Adsorption Properties of Lithum Ion (전자선 조사에 의한 다관능 Polypropylene-g-(acrylic acid/styrene) 섬유상 이온교환체의 합성과 리튬이온 흡착특성)

  • 황택성;박진원;이재천
    • Polymer(Korea)
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    • v.24 no.6
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    • pp.763-769
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    • 2000
  • The multifunctional cation exchangers, sulfonated polypropylene-g-(acrylic acid/styrene) [PP-g-(AAc/Sty)] were synthesized by the irradiational grafting of AAc and Sty onto PP staple fabric with electron beam accelerator and its subsequent sulfonation. The highest degree of grafting obtained was 190% at a monomer mixture of 30 vol% AAc: 70 vol% Sty and a solvent mixture of 30 vol% water : 70 vol% methanol and the degree of grafting decreased with an increase of the AAc content in the monomer mixture at constant solvent content. Maximum ion exchange capacity of the copolymer was 4.6 meq/g. The Li$^{+}$ adsorption ability of the copolymer synthesized in the study was the best among PP-g- AAc, sulfonated PP-g-Sty, and sulfonated PP-g-(AAc/Sty).).

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Surface Modification of Polypropylene Fiber by Plasma Discharge (방전처리에 의한 Polypropylene섬유의 표면개질)

  • 허만우;이창재;강인규;한명호;김삼수;임학상
    • Textile Coloration and Finishing
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    • v.11 no.2
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    • pp.27-37
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    • 1999
  • Polypropylene(PP) films were treated with plasma glow discharge to produce peroxy radicals on the surfaces. The peroxy radicals formed on the PP film surfaces were subsequently used for the graft polymerization of acrylic acid and acrylamide in an aqueous solution by heating, respectively. Introduction of acrylic acid and acrylamide on the PP film could be confirmed by the observation of carbonyl and primary amine absorptions based on carboxylic acid and amide, respectively. And introduction of functional group could be confirmed by weight analysis and ESCA. The water contact angle(90$^{\circ}$) of PP film was constant, irrespective of elapsed time, while plasma-treated and functional monomer-grafted PP films were slowly increased with elapsed time, showing the rearrangement of surface polar groups in air condition. The water contact angle$(90^\circ)$ of PP film was decreased by the plasma treatment$(56^\circ)$ and further decreased by the grafting of acrylic acid$(34^\circ)$ and acrylamide$(37^\circ)$, indicating increased hydrophilicity of the modified surfaces. The water contact angle of plasma-treated PP film increased a little as time elapsing. The half-life periods of surface voltage on acrylic acid-(31sec) and acrylamide-grafted PP(42sec) were significantly decreased when compared to those on PP(950sec) and plasma-treated PP film(241sec). In the experiments using acid, basic and disperse dyes, absorbance and $\Delta{E}$ values of functional monomer-grafted PP films were significantly increased than that of oxygen plasma-treated one.

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Multiple Inheritance and English Locative Inversion

  • Chung, Chan
    • Language and Information
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    • v.5 no.1
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    • pp.55-71
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    • 2001
  • One of the controversial issues in English locative inversion (LI) construction( e. g. Under the tree sat a woman) has been the functional status of preverbal PP and postverbal NP, i.e. whether they are a subject, a complement, or filer (topic) Based on the distributional parallelisms between the PP and NP on the one hand and an ordinary subject and filler on the other this paper proposes that the PP has a dual function as a subject and filler, while the NP also has some subject properties that the PP does not have These mixed functional properties are analyzed in the theory of HPSG expecially with the versions recently developed by Sag(1997) Manning and Sag(1999) and Ginzburg and Sag(to appear). This analysis claims that the LI construction needs to satisfy two general, independent constraints head-subject- phrase and head-filler-phrase. This position suggests that the English LI construction is an instance of the peripheral phenomena whose construction specific constraint is inherited from more general core constraints. (Dongseo University)

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Enhanced Induction of T Cell Immunity Using Dendritic Cells Pulsed with HIV Tat and HCMV-pp65 Fusion Protein In Vitro

  • Park, Jung-Sun;Park, Soo-Young;Cho, Hyun-Il;Sohn, Hyun-Jung;Kim, Tai-Gyu
    • IMMUNE NETWORK
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    • v.11 no.3
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    • pp.182-189
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    • 2011
  • Background: Cytotoxic T lymphocytes (CTLs) appear to play an important role in the control and prevention of human cytomegalovirus (HCMV) infection. The pp65 antigen is a structural protein, which has been defined as a potential target for effective immunity against HCMV infection. Incorporation of an 11 amino acid region of the HIV TAT protein transduction domain (Tat) into protein facilitates rapid, efficient entry into cells. Methods: To establish a strategy for the generation of HCMV-specific CTLs in vitro, recombinant truncated N- and C-terminal pp65 protein (pp65 N&C) and N- and C-terminal pp65 protein fused with Tat (Tat/pp65 N&C) was produced in E.coli system. Peripheral blood mononuclear cells were stimulated with dendritic cells (DCs) pulsed with pp65 N&C or Tat/pp65 N&C protein and immune responses induced was examined using IFN-${\gamma}$ ELISPOT assay, cytotoxicity assay and tetramer staining. Results: DCs pulsed with Tat/pp65N&C protein could induce higher T-cell responses in vitro compared with pp65N&C. Moreover, the DCs pulsed with Tat/pp65 N&C could stimulate both of $CD8^+$ and $CD4^+$ T-cell responses. The T cells induced by DCs pulsed with Tat/pp65 N&C showed higher cytotoxicity than that of pp65-pulsed DCs against autologous lymphoblastoid B-cell line (LCL) expressing the HCMV-pp65 antigen. Conclusion: Our results suggest that DCs pulsed with Tat/pp65 N&C protein effectively induced pp65-specific CTL in vitro. Tat fusion recombinant protein may be useful for the development of adoptive T-cell immunotherapy and DC-based vaccines.

A Threats Statement Generation Method for Security Environment of Protection Profile (PP의 보안환경을 위한 위협문장 생성방법)

  • 고정호;이강수
    • The Journal of Society for e-Business Studies
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    • v.8 no.3
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    • pp.69-86
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    • 2003
  • A Protection Profile(PP) is a common security and assurance requirements for a specific class of Information Technology security products such as firewall and smart card. A PP should be included "TOE(Target of Evaluation) Security Environment", which is consisted of subsections: assumptions, treat, organizational security policies. This paper presents a new threats statement generation method for developing TOE security environment section of PP. Our survey guides the statement of threats in CC(Common Criteria) scheme through collected and analysed hundred of threat statements from certified and published real PPs and CC Tool Box/PKB that is included a class of pre-defined threat and attack statements. From the result of the survey, we present a new asset classification method and propose a threats statement generation model. The former is a new asset classification method, and the later is a production rule for a well formed statement of threats.

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Synthesis of Aminated PP-g-styrene Fibrous Ion-Exchanger for Separation of Boron from Ground-Water (지하수로부터 붕소이온 분리를 위한 아민화 PP-g-styrene 이온교환체 섬유의 합성과 붕소 음이온 흡착에 관한 연구)

  • Hwang, Taek-Sung;Lee, Jin-Hyok;Lee, Myun-Joo
    • Polymer(Korea)
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    • v.25 no.4
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    • pp.451-459
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    • 2001
  • Fabric ion-exchanger, aminated PP-g-styrene was synthesized with styrene monomer onto PP staple fiber by pre-irradiational grafting with E-beam and subsequent chloromethylation and amination. Degree of grafting was increased with increasing the styrene monomer concentration and the highest degree of grafting was obtained 118% at a monomer concentration of 80% styrene. Optimum condition of Mohr's salt and sulphuric acid were 1.0 ${\times}\;10^{-3}$ M and 0.1 M. Amount of amination was increased with increasing degree of grafting. Swelling ratio of aminated PP-g styrene was higher than that of trunk polymer. Ion-exchange capacity was 6.7 meq/g, which was three times greater than commercial ion-exchanger. Optimum condition of baron ion adsorption was pH 4 and amount of adsorption were increased with increasing the amount of amination.

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Design and Performance Analysis of Electronic Seal Protection Systems Based on AES

  • Kim, Dong-Kyue;Lee, Mun-Kyu;Kang, You-Sung;Chung, Sang-Hwa;Yoon, Won-Ju;Min, Jung-Ki;Kim, Ho-Won
    • ETRI Journal
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    • v.29 no.6
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    • pp.755-768
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    • 2007
  • A very promising application of active RFID systems is the electronic seal, an electronic device to guarantee the authenticity and integrity of freight containers. To provide freight containers with a high level of tamper resistance, the security of electronic seals must be ensured. In this paper, we present the design and implementation of an electronic seal protection system. First, we propose the eSeal Protection Protocol (ePP). Next, we implement and evaluate various cryptographic primitives as building blocks for our protocol. Our experimental results show that AES-CBC-MAC achieves the best performance among various schemes for message authentication and session key derivation. Finally, we implement a new electronic seal system equipped with ePP, and evaluate its performance using a real-world platform. Our evaluation shows that ePP guarantees a sufficient performance over an ARM9-based interrogator.

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