• Bulletin of the Korean Chemical Society
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• 제23권11호
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• pp.1595-1603
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• 2002

In this paper we have presented the results of diffusion behavior of model systems for eight liquid n-alkanes ($C_{12}$-$C_{44}$) in a canonical (NVT) ensemble at several temperatures using molecular dynamics simulations. For these n-alkanes of small chain length n, the chains are clearly <$R_{ee}^2$>/6<$R_g^2$>>1 and non-Gaussian. This result implies that the liquid n-alkanes over the whole temperatures considered are far away from the Rouse regime, though the ratio becomes close to the unity as n increases. Calculated self-diffusion constants $D_{self}$ are comparable with experimental results and the Arrhenius plot of self-diffusion constants versus inverse temperature shows a different temperature dependence of diffusion on the chain length. The global rotational motion of n-alkanes is examined by characterizing the orientation relaxation of the end-to-end vector and it is found that the ratio ${\tau}1/{\tau}2$ is less than 3, the value expected for a isotropically diffusive rotational process. The friction constants ${\xi}$of the whole molecules of n-alkanes are calculated directly from the force auto-correlation (FAC) functions and compared with the monomeric friction constants ${\xi}_D$ extracted from $D_{self}$. Both the friction constants give a correct qualitative trends: decrease with increasing temperature and increase with increasing chain length. The friction constant calculated from the FAC's decreases very slowly with increasing temperature, while the monomeric friction constant varies rapidly with temperature. By considering the orientation relaxation of local vectors and diffusion of each site, it is found that rotational and translational diffusions of the ends are faster than those of the center.

• 정보화정책
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• 제28권2호
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• pp.3-33
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• 2021

본 논문의 목적은 4차 산업 핵심 기술 중의 하나인 블록체인에 대한 비즈니스적 관점의 해석을 통해 기술과 경영의 괴리를 축소하여 블록체인의 비즈니스화를 촉진하고, 동 분야에 대한 국내외 연구 동향을 분석하여 향후 연구방향을 제시하기 위함이다. 본 연구에서는 '구글학술검색', 'ScienceDirect' 및 'DBpia'를 통해서 식별된 블록체인 관련 연구문헌과 블록체인 기반 공급망 추적성 분야의 연구논문(해외 109편, 국내 6편)을 분석한 결과를 요약하면 다음과 같다. (1) 분산애플리케이션을 지향하는 3세대 블록체인이 등장한 이후 관련 연구가 활성화되고 있다. (2) 주요 연구분야는 기술(공학) 분야는 블록체인의 확장성 영역에, 비즈니스(적용) 분야는 블록체인기반 공급망 추적성 분야에 집중되어 있다. (3) 해외에 비해 국내 연구결과는 매우 열악하다. (4) 향후 4차 산업 사회의 구현과 글로벌 협업을 위해 블록체인을 기술이 아닌 비즈니스 서비스의 수단이라는 인식이 확산되어야 할 것이다.

• 유통과학연구
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• 제14권6호
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• pp.65-73
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• 2016

Purpose - Recently, the management conditions of small independent retailers are getting worse everyday as large-scale marts and franchised convenience stores are increasing. The objective of this research is to find out the antecedents and consequences of cooperation in voluntary chain in order to enhance small independent retailer's competitiveness. Voluntary chains, also called affiliation or symbol groups, or allied group represent a high market shared in some European countries like Italy, France, and Germany. Nevertheless, there are still limitations in this research from academic fields. Drawing from network theory, the author investigates the relationship between antecedent factors in voluntary chain cooperation, such as participation benefits, justice of compensation, and autonomy in voluntary chain, and relationship specific asset. The author also attempts to examine the relationship between the relationship specific asset and cooperation of voluntary chain member shop and cooperation and consequence factors of voluntary chain cooperation, such as efficiency, group cohesiveness, and long-term relationship. Research design, data, and methodology - The author presented conceptual framework integrating the major antecedents and consequences of voluntary chain cooperation. The data were collected from 174 independent small retailers who joined K-voluntary chain. K-voluntary chain consists of small independent retailers. In accordance with their status, each entrepreneur associated with the voluntary group can own one or more outlets and can be a part of the life and the decision-making process of the group. This participation is not based on company turnover or on the number of outlets, but based on a one member, one vote system. To verify the research model and test hypotheses, the author carefully investigated the reliability, content validity, convergent validity, and discriminant validity of the proposed model. The data were analyzed by using SPSS 18.0 and AMOS structural equation modeling program. Results - The results of this study are as follows. First, as antecedent variables, participation benefits and justice of compensation have positive effect on the relationship specific assets of voluntary chain members. Second, voluntary chain members' relationship specific asset also directly related to the level of its cooperation to chain headquarter. Third, cooperation of voluntary chain member shop facilitates efficiency, group cohesiveness, and long-term relationship. Unexpectedly, there are no effect autonomy in voluntary chain to relationship specific asset. Conclusions - This research shows several theoretical and practical implications to both marketing scholars and marketers. In terms of theoretical implications, this study applies to network theory and network theory variables to explain the antecedent and consequence factors of cooperation in voluntary chain. From the point of view from business management, most of all, this study shows the way how to reinforce competitiveness of voluntary chain. Specifically, it is necessary for voluntary chain headquarter to give higher level of participation benefit and justice of compensation to its members. Second, the results also indicate what the consequence factors of cooperation in voluntary chain. In other words, to increase the level of marketing efficiency, group cohesiveness, long-term orientation in retail voluntary chain, and chain headquarter need to facilitate participants' cooperation.

• 대한토목학회논문집
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• 제31권2D호
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• pp.275-284
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• 2011

Supply Chain Management는 제조업에서 부가가치의 60~70%가 제조과정 외부의 Supply Chain(공급체인망) 상에서 발생하는 특성을 가지고 있다. 여기에 기업 간의 경쟁이 치열해짐에 따라 효율적인 프로세스 형성을 위해 비용 및 공정 개선을 위한 노력이 선행되고 있으며, 고객지향, 고객만족, 시장요구에 대한 적응을 위해 공급체인의 혁신을 위한 중요성이 강조되고 있다. 그러나 현 건설산업에서는 협력업체와의 계급적인 구조 문제와 협력업체와의 관계 개선을 위한 의식부족 등으로 인해 SCM의 적용에 많은 어려움이 있다. 건설산업에서도 제조업과 마찬가지로 일부특성상의 상이점이 있지만, SCM의 적용을 통해 건설산업에서의 효율적인 업무 프로세스 개선을 위한 다양한 SCM 연계활동이 가능할 것으로 판단된다. 따라서 본 연구를 통해 건설산업 분야에서의 SCM 전문 교육 프로그램의 개발을 통해 건설 SCM 전문가의 육성과 함께 건설 SCM의 적용을 위한 활성화가 이루어질 수 있는 기틀을 마련하고자 한다.

• Bulletin of the Korean Chemical Society
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• 제22권8호
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• pp.872-876
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• 2001

Topological changes caused by the alkaline and enzymatic attacks of solution-grown, chain-folded lamellar crystals (SGCs) of poly[(R)-3-hydroxybutyrate] P(3HB) have been studied in order to investigate the chain-folding structure in P(3HB) crystal regions. NaOH and an extracellular PHB depolymerase purified from Alcaligenes faecalis T1 were used for alkaline and enzymatic hydrolysis, respectively. The measurements were performed on crystals attached to a substrate which is inactive to degradation mediums. Both alkaline and enzymatic attacks lead to a breakup of the lamellar crystals along the crystallographic b-axis during initial erosion. Since hydrolysis preferentially occurs in amorphous regions, this morphological result reflects relatively loosely packed chains in core parts of lamellar crystals. Additionally, it was supported by the ridge formation along the b-axis in the lamellar crystals after thermal treatment at a low temperature because of the thermally sensitive nature of the loosely packed chains in lamellar crystals. However, the alkaline hydrolysis accompanied the chain erosions or scissions in quasi-regular folded lamellar surfaces due to smaller size of alkaline ions in comparison to the enzyme, resulting in the decrease of molecular weight.

• 한국항만경제학회지
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• 제29권4호
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• pp.201-222
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• 2013

본 연구는 다국적 기업들이 그들의 글로벌 공급사슬을 얼마나 지식이라는 전략적 자원에 기초하여 조직하고 운영하고 있는지, 그리고 지식을 지향하는 공급사슬관리가 기업의 글로벌 공급사슬관리 성과에 어떠한 영향을 미치는지를 분석하는데 목적을 두고 있다. 이를 위해 Nonaka(1994) 등이 제시한 지식창조 프로세스를 적용하여 지식지향 글로벌 공급사슬관리의 개념을 구체화하는 측정모형을 제안하였으며 기업의 지식경영 시스템과 지식창조 프로세스가 기업의 글로벌 공급사슬관리 성과에 어떠한 영향을 미치는지를 실증적으로 분석하였다. 113개의 다국적 기업을 대상으로 한 실증분석을 통해 본 연구에서 제안한 측정모형의 타당성과 신뢰성을 검증하였다. 또한 표본 기업들을 글로벌 공급사슬관리에 있어서의 지식지향 수준에 따라 군집화하여 비교분석한 결과, 글로벌 공급사슬상에서 창출되는 지식을 효과적으로 관리하는 기업들이 글로벌 공급사슬관리 성과에 있어서도 전반적인 우위를 나타내는 것으로 분석되었다.

• 한국정밀공학회지
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• 제16권2호통권95호
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• pp.39-49
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• 1999

This paper describes the development of a vision-aided position and orientation recognition system for automatically adjusting electronic tuners which control the waveform by rotating variable resisters. The position and orientation recognition system estimates the center and the angle of the tuner grooves so that the main controller may correct the difference from the ideal position and thereby manipulate the variable resisters automatically. In this paper a robust algorithm is suggested which estimates the center and the angle of the tuner grooves fast and precisly from the source image with lighting variance and video noise. In the algorithm morphological filtering, 8-chain coding, and invariant moments are sequentially used to figure out image segments concerned. The performance of the proposed system was evaluated using a set of real specimens. The results indicate the system works well enough to be used practically in real manufacturing lines. If the system adopts a high speed frame grabber which enables real time image processing, it can also be applied to positioning of robot manipulators as well as automated PCB adjusters.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.311-311
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• 2006

The morphology of Poly(styrene-b-methylmethacrylate) (P(S-b-MMA)) block copolymer thin films deposited on silicon wafers was controlled by treating the substrates with Self-Assembled Monolayers (SAM) of phenylsilanes with different alkyl chain lengths. It was found that the treatment with SAM strongly modified the substrates properties, especillay the surface energy, as compared with bare silicon oxide. By futher adjusting the molecular weight of P(S-b-MMA), a variety of morphologies could be generated, including a perpendicular orientation of lamellea of PS and PMMA, which is required for industrial applications.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.5-8
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• 1997

A study on the electrical conduction characteristics of the ultrathin organic films is one of the important factors for the development of molecular electronic devices. The Langmuir- Blodgett(LB) technique has recently been attracted interest as a method of the deposition ultrathin films. We hate fabricated N-docosyl N\`-methyl viologen-diTCNQ(DMVT) anion radical LB film and investigated the molecular orientation and electrical conduction characteristics. We have measured infrared transmission-reflection spectra. The alkyl chain is found to he well-ordered with the tilt angle of 13$^{\circ}$ with respect to the substrate surface normal and the TCNQ plane is tilted at 76$^{\circ}$ the surface normal. In ESR spectrum, we confirmed that a half-amplitude linewidth is clearly dependent on the incident angle, which indicates conducting species change. The in-plane conductivity of 31 lagers is approximately 1.33$\times$10$^{-6}$ S/cm. The ohmic behaviour was observed below 0.6 V, when current-voltage(I-V) characteristics was measured verically.

• 대한수학회논문집
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• 제39권3호
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• pp.643-645
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• 2024

In this note, we aim to correct some of the results presented in [1]. Namely, the statements of Proposition 2.1, Corollary 2.2, Corollary 2.3, Theorem 2.4 and Theorem 2.6, concerning only the monoids 𝓞𝓟_n and 𝓟𝓞𝓟_n, have to exclude transformations of rank two. All other results of [1], as well as those mentioned above but for the monoids 𝓞𝓡_n and 𝓟𝓞𝓡_n, do not require correction.