• Title/Summary/Keyword: chain orientation

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Comparison of Effects of Ultraviolet and $^{60}$ Co Gamma Ray Irradiation on Nylon 6 Mono-filaments

  • Ohtsuka, Mika;Suzuki, Yoshino;Sakai, Tetsuya;Netravali, Anil N.
    • Fibers and Polymers
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    • v.5 no.3
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    • pp.225-229
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    • 2004
  • The effect of UV and $^60{Co}$ gamma radiations on the physical and mechanical properties of nylon 6 mono-filaments with different draw ratios has been studied. Specimens were exposed to either up to 25 Mrad of gamma or up to 168 hrs of intense UV irradiation. The results show that nylon mono-filaments exposed to gamma rays, with much higher quantum energy than UV, undergo a larger extent of molecular chain scission. Higher irradiation dose also results in the production of insoluble, macroscopic three-dimensional cross-linked network structure. The amorphous regions with a lower density of cohesive energy (lower molecular orientation) show a higher extent of cross linking reaction whereas amorphous regions with a higher density of cohesive energy (higher orientation) show higher extent of chain scission reaction, irrespective of UV ray or gamma ray irradiation.

Effect of Uniaxial Drawing Conditions on the Orientation of Poly (ethylene 2,6- naphthalate) (일축 연신 조건에 따른 Poly(ethylene 2,6-naphthalate) 배향에 관한 연구)

  • 진병석;이성효;이광희
    • Polymer(Korea)
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    • v.25 no.5
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    • pp.699-706
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    • 2001
  • The effects of uniaxial drawing conditions on the molecular orientation of poly (ethylene 2,6-naphthalate) (PEN) are investigated. Birefringence measurements show that the orientation is significantly enhanced at high draw ratio, low drawing temperature, and fast drawing speed. The characteristics of orientation examined by FTIR- ATR dichroism method represent almost same results. Amorphous orientation function increases with drawing rate at $120^{\circ}C$, but it decreases with drawing rate at $141^{\circ}C$. These behaviors can be explained with the relation between crystallization and chain relaxation rates. It is observed that the orientation of PEN film is accompanied by significant alignment of the naphthalene rings of PEN parallel to the film surface.

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A Study on the Molecular Orientation and the Surface Mophology of polyimide precursor ultrathin film (폴리이미드 전구체 초박막의 분자배향과 표면상태에 관한 연구)

  • Jeong, Soon-Wook
    • Journal of the Korean Applied Science and Technology
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    • v.22 no.3
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    • pp.228-233
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    • 2005
  • Langmuir-Blodgett(LB) technique can speak the best candidate of the future molecular electronic devices. But, precursor as molecular ultrathin film devices require the bulk property that are influenced by the molecular orientation. So, this device is one of current interest in molecular electronic device development of new materials. In this study, quantitative evaluation of molecular orientation in LB films of polyamic acid alkylamine salt was performed analysis experiment comparing the absorption or transmission intensity of the FT-IR spectrometer and reflection or absorption spectra with UV-visible absorption spectra. It could find that the polar angle(${\theta}$) of the dipole moment appears in about $68^{\circ}$ and the tilting angle of the alkyl chain is about $11.5^{\circ}$.

The Apparel Purchasing Behavior of Adolescent groups Segmented by their Brand Orientation (청소년의 상표지향성에 따른 의복구매행동)

  • 주성래;정명선
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.2
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    • pp.230-241
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    • 1999
  • The purpose of this study was to investigate the purchasing behavior of adolescent consumer groups divided by their brand orientation. Questionnaires were administered to 507 middle and high school students who resided in Kwang-ju between September 22-27 1997. Data were analyzed by factor analysis cluster analysis ANOVA Duncan-test frequency and {{{{ chi ^2 }}-test. The results were as follows : 1. Adolescent consumers were classified by three groups ; brand attached groups : brand attached group (Group I) brand interest group (Group II) and brand indifference group (Group III) according to their brand orientation. 2. There were significant differences among groups in using information sources : Group II used more sources of information than the other two groups. 3. As evaluating attributes of product Group I considered brand prestige most important Group II considered design fashionablity imfortant orderly and Group III considered pricemost important. 4. Group I patronised expensive brand chain stores Group II patronseied department stores and Group III prefered independently owned cheaper priced retailers. 5. The apparel purchasing price range was higher for Group I and became lower for Group II Group III.

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Automatic Control Point Measurement and Photo Orientation via Matching with Control Patch

  • Jaw, Jen-Jer;Wu, Yi-Shen
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.375-377
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    • 2003
  • In this study, we employ the control patches, which have been created in previous photogrammetric projects, serving for the candidates of the control points that are likely to be found in the newly taken photos by utilizing image matching technique. Among others, the successful implementation of the above idea lies in the underlying factors: (1). Predicting the control patches and projecting them onto new photos; (2). Alignment of control patches with respect to the new photos; (3). Generating the equivalent ground elements of control patches versus the new photos for the purpose of correlation; (4). Developing effective matching methods and matching strategy; (5). Refining the exterior orientation parameters. What may show significance in this work comparing to traditional aerial-triangulation chain is that whenever at least three matched control patches succeed in a single photo, it follows that single photo orientation is applicable. The experiments suggest the potential efficiency of automatic control point measurement from control patch database and photo orientation by the proposed workflow.

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Case Analysis of Industry-Oriented Collegiate Curriculum Development and Implementation in the IT Sector: A Supply Chain Management Approach (현장수요 지향적 대학IT 교과과정 개발 및 운영 사례연구 : 공급사슬관리적 접근)

  • Om, Ki-Yong;Lee, Jae-Won;Yoon, Suk-Cheon
    • The Journal of Korean Institute for Practical Engineering Education
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    • v.2 no.1
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    • pp.8-16
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    • 2010
  • Confronted with serious problems in nurturing IT engineers such as a mismatch in supply and demand of IT workers, shortage of globally competitive IT professionals, and insufficient education and training of university graduates, the Ministry of Information and Communication has decided to adopt a new approach in national IT engineering education, based on supply chain management (SCM) in manufacturing. SCM weighs improving competitiveness of the supply chain as a whole via a long-term commitment to supply chain relationships and a cooperative, integrated approach to business processes. These benefits of SCM are believed to provide useful insight into a more effective IT education and industry orientation. On the basis of the SCM literature, a framework for industry-oriented practical IT higher education is designed, and then applied in the field of computer-software engineering in Korea.

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A Study of the Competitive Factors of ICT Venture and SMEs in the Global Digital Ecosystem (벤처·중소 ICT 기업의 디지털 생태계에서의 글로벌 경쟁력 요인 연구)

  • Lee, Kae Soo;Yoon, Heon-Deok
    • Journal of Information Technology Services
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    • v.15 no.1
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    • pp.1-18
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    • 2016
  • Recently, in the bio-field success stories of ventures through a biosimilar technology is being excavated. but the growth of ICT industry has been stagnant since reaching a boom in the dissemination of early high-speed internet in 2000s. The purpose of this study is to explore the factors of change of business model and business strategy of ICT ventures and SMEs with the evolution of the digital ecosystem, and to drive the factors to be competitive on the global value chain. The researcher selected an entreprenuership, market-innovation orientation, technology-innovation orientation, and Administration-innovation orientation as internal factors influencing the global competence and healthiness of the ecosystem as external factors. The researcher applied samples of 94 ICT Venture and SMEs to a research model, and adopted 5 hypotheses. The researcher believes that only a few hypotheses were adopted because it takes time for overall innovation orientation of ICT Venture and SMEs to result in the real global competence as the their innovation orientation is still on the level of domestic market. And the researcher also thinks that only healthiness of the ecosystem affected management performances because the companies' performances of the last 3 years were so weak that the correlation between innovation orientation of each company and the performances were not big enough.

The Role of Relational Capital in Supply Chain Management for Distribution Service Firms (유통서비스 기업의 공급사슬 운영성과 경로에서 파트너 관계자산의 역할)

  • Cho, Yeon-Sung
    • Journal of Distribution Science
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    • v.13 no.11
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    • pp.111-121
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    • 2015
  • Purpose - This study's purpose is to investigate the impact of supply chain management (SCM) factors among targeted Korean distribution firms. Antecedents are established for supply chain orientation (SCO) for the management and organization of cultural assets. The research sets up SCO corresponding to management cultural assets and to organizational factors in the results. The research model is created to examine the SCO based on a strategic perspective and the operational performance of the SC and SCM. In addition, an integrated model is constructed to analyze the moderating effect by setting partner cooperation as a relational capital factor. The main aim of this study is to analyze the characteristics of the supply chain structure as a source of competitive advantage for distribution service firms participating in the supply chain. In the moderating effects analysis, the role of partner cooperation as relational capital is examined in detail. Research design, data, and methodology - The study examined the existing research related to supply chains, discussing the antecedents of the performance of SCM and SCO. SCM was established with the partner's cooperation as relational capital. Including the moderating effects of the partner cooperation, the research proposed a seven hypotheses path analysis model. The samples were collected from the Korean export enterprises in the distribution service sector, with 185 samples selected for the final analysis. To try and measure the four latent variables presented in the analysis model based on existing studies, 22 measurement items were used. The empirical analysis used the appropriate PLS (partial least squares) method on the path analysis reliability and validity and for common method bias. After testing the seven hypotheses, the research tested the moderating effects to the path analysis. Using PLS as structural equation modeling, the seven hypotheses were tested including the moderating effects of the partner relational capital on the 185 samples. Results - In the results, the SCO had a positive impact on both SCM and the relational capital of partner cooperation. The SCM had a significant impact on the operational performance of the SC. Further, partner cooperation also had a significant impact on SCM and the operational performance of the SC. The moderating effect analysis of the SCM and partner cooperation found a significant impact on the operational performance of the SC. On the other hand, the moderating effect of the SCO and partner cooperation did not affect the SCM. Conclusion - The results of this research show that the existing supply chain-related research can be applied to the operational performance of the SC for a Korean distribution service firm. In view of the fact that SCO is a source of competitive advantage, it should be taken into account when a firm wants to improve the performance of the SCM of the distribution service. This is because it can be assumed that SCO plays a role in supply chain management for the distribution firm.

Effects of Physico-chemical Factors of Sol on the Degree of Preferred Orientation in $Pb(Mg, Zn)_{1/3}Nb_{2/3}O_3$ Thin Films (Sol의 물리화학적 변수들이 $Pb(Mg, Zn)_{1/3}Nb_{2/3}O_3$ 박막의 우선 배향성에 미치는 효과)

  • 조문규;장현명;김광수
    • Journal of the Korean Ceramic Society
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    • v.32 no.3
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    • pp.305-312
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    • 1995
  • Thin films of Pb(Mg, Zn)1/3Nb2/3O3 were fabricated by spin coating the Pb-Mg-Zn-Nb-O complex alkoxide sols on(111) Pt-coated MgO (100) planes. It was observed that the content of H2O and the rheological characteristics of sol greatly influenced the orientation of perovskite grains after thin-film formation. A strong preferential orientation of (100)-type planes of the perovskite grains was obtained for the sol aged for 15 days with the molar ratio of H2O to total metal alkoxides=2. As small angle X-ray scattering experiment in the Porod region was performed to correlate the observed preferential orientation with the network structure of precursors at various stage of aging. It was shown that the degree of branching of the Pb-Mg-Zn-Nb-O precursor chain had a direct effect on the preferred oreintation, and weakly branched precursor systems led to highly oriented grains after thin-film formation.

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Residual Stress Behavior of High Temperature Polyimide Thin Films depending on the Structural Isomers of Diamine (Diamine의 구조적 이성질체에 따른 내열성 폴리이미드 박막의 잔류응력거동)

  • 임창호;정현수;한학수
    • Journal of the Microelectronics and Packaging Society
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    • v.6 no.2
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    • pp.23-30
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    • 1999
  • The relationships between morphological structures and residual stress behaviors of polyimide thin films depending on isomeric diamines were investigated. For this study, Poly(phenylene biphenyltetracarboximide) (BPDA-PDA) and poly(oxydiphenylene biphenyltetracarboximide) (BPDA-ODA) films were prepared from their isomeric diamines: 1,3-phenylene diamine (1,3-PDA) 1,4-phenylene diamine (1.4-PDA), 3,4'-oxydiphenylene diamine (3,4'-ODA), and 4,4'-oxydiphenylene diamine (4,4'-ODA), respectively. For those films, residual stresses were detected in-situ during thermal imidization of the isomeric polyimide as a function of processing temperature over the range of 25~$400^{\circ}C$ using. Thin Film Stress Analyzer (TFSA). In comparison, residual stress of BPDA-1.4PDA having better in-plain orientation and chain order was the lowest value of 7MPa whereas those of BPDA-1,3-PDA, BPDA-3,4'-ODA, and BPDA-4,4'-ODA were in the range of 40-50MPa. Conclusively, the effect of morphological nature (chain rigidity, chain order, orientation) and chain mobility relating to the g1ass transition behavior on the residual stress of isomeric polyimide thin films wart analyzed.

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