• Title/Summary/Keyword: Chain Structure

Search Result 1,301, Processing Time 0.027 seconds

Molecular Dynamics Simulation for Bilayers of Alkyl Thiol Molecules at Solid-Solid Interfaces

  • 이송희;김한수;박형숙
    • Bulletin of the Korean Chemical Society
    • /
    • v.19 no.10
    • /
    • pp.1047-1054
    • /
    • 1998
  • We present the results of molecular dynamics simulations for three different systems of bilayers of long-chain alkyl thiol [S(CH2)15CH3] molecules on an solid-solid interface using the extended collapsed atom model for the chain-molecule. It is found that there exist two possible transitions: a continuous transition characterized by a change in molecular interaction between sites of different chain molecules with increasing area per molecule and a sudden transition from an ordered lattice-like state to a liquid-like state due to the lack of interactions between sites of chain molecules on different surfaces with increasing distance between two solid surfaces. The third system displays a smooth change in probability distribution characterized by the increment of gauche structure in the near-tail part of the chain with increasing area per molecule. The analyses of energetic results and chain conformation results demonstrate the characteristic change of chain structure of each system.

A Design of Peer-to-Peer Based IPTV System using Multiple Chain Architecture (다중 체인구조를 이용한 Peer-to-Peer 기반 IPTV 시스템 설계)

  • Kim, Ji-Hoon;Kim, Young-Han
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.45 no.12
    • /
    • pp.74-82
    • /
    • 2008
  • In this paper, we propose a P2P based IPTV system using a multiple chain architecture. Proposed system is robust to the peer churn. As opposed to the internet the IPTV network managed by a single ISP has fewer bandwidth constraints and end-to-end connectivity. So, we emphasize preferentially robustness of a P2P network in IPTV environment. A single chain structure which was proposed previously emphasizes simplicity, however there exists considerable delay time at the end part of peers as the number of peers increasing. As a solution to the problem, we propose the scheme which seperates the chain into several levels and again divides each level into spans to diminish a delay time. Though the chain is separated into level and span, basic structure of proposed scheme is still a chain structure. So the scheme simplifies the recovery procedure caused by join or departure of peers. We will show the improved performance of proposed scheme rather than single chain structure with respect to the delay time and reliability.

An Empirical Study on Value-Chain Network of Manufacturing and Implications on Cluster Policy (제조업의 가치사슬 네트워크 분석과 클러스터정책에 대한 시사점)

  • Kim, Yo-Han;Shim, Seung-Jin
    • Journal of Technology Innovation
    • /
    • v.15 no.1
    • /
    • pp.203-233
    • /
    • 2007
  • This study investigates how characteristics in the value-chain industrial cluster affect the R&D investment and the output of firms in each industries. For this, we try to extract the inter-industrial networking structure from the input-output table in which 17 manufacturing sectors are included. In particular, we will give shape to the "unit structure" which shows the intermediary flows of goods and services between industries in order to get an unit of final demand in a certain industry. Using this "unit structure", we can try the inter-industrial networking analysis and get some indices of centrality and centralization related to the characteristics of each industries in the value-chain industrial cluster. The results show that the centrality in the value-chain industrial cluster does not have any consequence for the R&D investment and the output in each industries. However, there is a correlation between the centralization in the value-chain industrial cluster and the R&D investment and the output of firms in each industries. These results may be very suggestive in bringing up a new frame of industrial cluster policy in a macro level.

  • PDF

A Study on the Supply Chain Security and Risk Management Strategies of Global Companies (글로벌 기업의 공급사슬보안 및 위험관리전략에 관한 연구)

  • Yang, Jung-Ho
    • Management & Information Systems Review
    • /
    • v.27
    • /
    • pp.149-172
    • /
    • 2008
  • Since the 9/11 terror attack, the event which caused supply chain disruption, supply chain security has becomes more important than ever before. Furthermore, such company's logistics strategies conflicting supply chain security as increased global sourcing, JIT manufacturing are increasing supply chain vulnerability. It could burden for global companies to strengthen supply chain security because not only it requires additional investment cost but also changes of companiy's global logistics strategy. However, on the other hand, supply chain visibility and resilience can be improved through supply chain security. In addition, it allows companies to stabilize supply chain structure as well as rapid and flexible response to market demand. The key issue is balancing between efficiency and supply chain security. To do this, identifying risk elements under the supply chain and assessing vulnerability of each supply chain components should be performed before developing efficient supply chain security management system without obstructing supply chain efficiency.

  • PDF

cDNA Cloning and Characterization of Type II Procollagen α1 Chain in the Skate Raja kenojei

  • Hwang Jae-Ho;Yokoyama Yoshihiro;Mizuta Shoshi;Yoshinaka Reiji
    • Fisheries and Aquatic Sciences
    • /
    • v.9 no.1
    • /
    • pp.22-29
    • /
    • 2006
  • We determined the partial cDNA of Type II procollagen ${\alpha}1$[pro-${\alpha}1$(II)] chain (1802 bp) of the skate Raja kenojei, which codes 581 amino acid residues. The partial structure of the pro-${\alpha}1$(II) chain consisted of a part of triple helical region (309 residues) and a C-domain (272 residues). Comparing the chain to other vertebrates showed relatively low homology (about 50%) at the amino acid level. However, eight Cys residues in the C-domain of the skate pro-${\alpha}1$(II) chain were conserved in common with those of other vertebrates. The skate pro-${\alpha}1$ (II) chain mRNA was detected by RT-PCR of various tissues, but was undetected in tissues containing Type II collagen. The low homology and unexpected expression pattern suggest the presence of another mRNA variant of the skate pro-${\alpha}1$(II) chain. The present study is the first report of the primary structure of pro-${\alpha}1$(II) chain in an elasmobranch.

Structural Analysis and Derivation of Vulnerability for BlockChain based System (블록체인 기반 시스템의 구조적 분석과 취약점 도출)

  • Kim, Jang-Hwan
    • Journal of Software Assessment and Valuation
    • /
    • v.15 no.1
    • /
    • pp.115-121
    • /
    • 2019
  • I analyzed the structure of a block-chain system and a block-chain-based service system. It is a decentralized book encryption system software technology that does not require a third party to secure trust between the two parties. Block chains are structured in a linked list structure. The block chain manage transaction information by blocking the transaction information, in conjunction with other blocks. As a result, I have discovered structural weaknesses in current block-chain systems and block-chain-based service systems. Once these possible structural problems are resolved, I expect that the block-chain-based service system will make various industrial contributions.

The effect of the structure of each component on the o/w microemulsion droplet size and stability

  • Changgui Han;You
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.22 no.2
    • /
    • pp.20-40
    • /
    • 1996
  • The oil in water type ME of 4 component system was composed with POE monoalkyl ether and POE sorbitan monoalkyl ester as surfactant, saturated hydrocarbon, side chain structure and aromatic structure as oil, and glycerine as cosurfactant using high pressure homogenizer. The objective of this study was to examine the role of surfactant and oil structure on droplet size and stability. The experimental results showed that the droplet size was smaller with bigger polarity of oil, less hydrocarbon, longer hydrophilic chain of surfactant and higher concentration of glycerine. SQ and LP systems showed very stable but AB and ISB system unstable microemulsion.

  • PDF

Structural Transcription of Organogels to Mesoporous Silicas: A Chain-length Dependent Morphology and Pore Texture

  • Huang, Yaqun
    • Bulletin of the Korean Chemical Society
    • /
    • v.33 no.11
    • /
    • pp.3711-3718
    • /
    • 2012
  • Here, we report a chain-length dependent morphology and pore structure tailing of mesoporous silica templated from organogels, which is formed by primary alkylamine and ethylene glycol at room temperature. As the chain length of alkylamine changes from 12 to 18, the resulted materials exhibit a morphology change from layers to spheres and platelets, respectively. SEM and TEM observation revealed that these shapes appear to be inherited from their parent organogels. Further pore structure characterization by nitrogen sorption analysis demonstrates that all the resulted silicas exhibit typical IV isotherms indicative of uniform mesopores, and their pore sizes are dependent on the chain length of alkylamine used.

A Study on Selection of Effective Supplier and Analysis of Evaluation Structure in Supply Chain Management (공급체인 관리하에서 효율적인 협력업체 선정 및 평가구조 분석에 관한 연구)

  • Kim, Jin-Ho;Lee, Byoung-Ki
    • IE interfaces
    • /
    • v.17 no.2
    • /
    • pp.169-179
    • /
    • 2004
  • In supply chain management, supplier capacity is very important to meet the customer demand quickly. This paper studies a supplier evaluation structure and then suggests a methodology using fuzzy theory for selecting an effective supplier. Several quantitative and qualitative evaluation factors should be analyzed in the evaluation structure. The qualitative factors includes not only product and service qualities but financial condition. The methodology deals with both the quantitative and qualitative factors together through fuzzy inference. A case study is also presented to show how to choose the best one among potential suppliers.