• 제목/요약/키워드: Chain Structure

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북천지역 자연학습 체험단지 초성을 위한 기본 계획(I) -하상분석, 대기질 및 생태분석- (Preliminary Design for Preparing a Natural Learning and Experimental Area in Bukchun and Boundary(I) - Analysis of Riverbed, Atmospheric and Ecological Environment-)

  • 정종현;최석규;조세환
    • 한국환경보건학회지
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    • 제28권2호
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    • pp.23-39
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    • 2002
  • This study focuses on the structure of geographical conditions, the riverbed, the meterological and atmospheric examination, the ecological environment, the food chain and the ecosystem, in order to establish a basic plan for preparing a natural learning area of environmental ecosystem in Bukchun and its surroundings, Gyeongju. The results could be summarized as follows. Bukchun is a first grade which extends 6km along the road from Bomun bridge to the junction of Hyungsangang. The basin area is 7.10$\textrm{km}^2$ and the slope is 1/200~1/300. Gyeongju has good atmospheric conditions, i.e. SO$_2$0.011 ~0.017ppm, CO 0.8~ 1.5ppm, NO$_2$0.013~0.019ppm, $O_3$0.013~0.020ppm, TSP 85~142$\mu\textrm{g}$/㎥, PM-10 47~90$\mu\textrm{g}$/㎥ and Pb 0.057 ~0.129$\mu\textrm{g}$/㎥, which is below the annual and daily averages, and is little lower than those of Pohang and Ulsan. The ecosystem of Bukchun is based on the structure of the food chain, which includes birds such as the grey and white herons at the top of the food chain. This study also considers the development of the river's in terms of culture, environment and ecology concept.

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

  • 이송희;김한수
    • Bulletin of the Korean Chemical Society
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    • 제17권8호
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    • pp.700-706
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    • 1996
  • We present the results of molecular dynamics simulations of monolayers of long-chain alkyl thiol [S(CH2)15CH3] molecules on an air-solid interface using the extended collapsed atom model for the chain-molecule and a gold surface for the solid surface. Several molecular dynamics simulations have been performed on monolayers with areas per molecule ranging from 18.30 to 32.10 Å2/molecule. It is found that there exist three possible transitions: a continuous transition characterized by a change in molecular configuration without change in lattice structure, a sudden transition characterized by the distinct lattice defects and perfect islands, and a third transition characterized by the appearance of a random, liquid-like state. The analysis of probability distributions of the segments shows that the structure of the chain-molecules at the air-solid interface is completely different from that at the air-water interface in the view of the degree of overlap of the probability distributions of the neighbor segments. The calculated diffusion coefficients of the chain-molecules on the monolayers seem to be not directly related to any one of the three transitions. However, the large diffusion of the molecules enhanced by the increment of the area per molecule may induce the second transition.

유비쿼터스 환경에서의 해양수산물 유통 가치사슬 혁신 및 전자상거래 시스템 구축에 관한 연구 (A Study on Restructuring of the Marine Products Value Chain and the Development of E-commerce Trading Systems in the Ubiquitous Environment)

  • 박명섭;김종욱;이원준;박상철
    • 한국IT서비스학회지
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    • 제5권2호
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    • pp.125-136
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    • 2006
  • In general, the distribution structure of marine products is very vulnerable to the uncertainties in the process from the production to the sale, and a lot of difficulty is thus inevitable in the supply control. Such a distribution structure is a very critical issue in securing the suability of marine products through systematic quality and hygiene control of marine products, and it is thus time to discuss the method to innovate and restructuring the distribution structure of marine products. From this point of view, this study approached the flow from production to consumption in view of SCM(supply chain management) beyond the partial discussion conducted so far for the distribution structure in the field of marine products. Further, this study suggested the establishment of electronic commerce systems with a traceability system built in RFID for marine products as an alternative of redesigning distribution infrastructure in the ubiquitous environment. From the results, we assured that such an electronic commerce system would be a new measure to improve the structure currently causing inefficiency and excessive distribution cost for the distribution structure of marine products.

Electronic Structure and Bonding in the Ternary Silicide YNiSi3

  • Sung, Gi-Hong;Kang, Dae-Bok
    • Bulletin of the Korean Chemical Society
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    • 제24권3호
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    • pp.325-333
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    • 2003
  • An analysis of the electronic structure and bonding in the ternary silicide YNiSi₃is made, using extended Huckel tight-binding calculations. The YNiSi₃structure consists of Ni-capped Si₂dimer layers and Si zigzag chains. Significant bonding interactions are present between the silicon atoms in the structure. The oxidation state formalism of $(Y^{3+})(Ni^0)(Si^3)^{3-}$ for YNiSi₃constitutes a good starting point to describe its electronic structure. Si atoms receive electrons from the most electropositive Y in YNiSi₃, and Ni 3d and Si 3p states dominate below the Fermi level. There is an interesting electron balance between the two Si and Ni sublattices. Since the ${\pi}^*$ orbitals in the Si chain and the Ni d and s block levels are almost completely occupied, the charge balance for YNiSi₃can be rewritten as $(Y^{3+})(Ni^{2-})(Si^{2-})(Si-Si)^+$, making the Si₂layers oxidized. These results suggest that the Si zigzag chain contains single bonds and the Si₂double layer possesses single bonds within a dimer with a partial double bond character. Strong Si-Si and Ni-Si bonding interactions are important for giving stability to the structure, while essentially no metal-metal bonding exists at all. The 2D metallic behavior of this compound is due to the Si-Si interaction leading to dispersion of the several Si₂π bands crossing the Fermi level in the plane perpendicular to the crystallographic b axis.

The Short-Chain Fatty Acid Receptor GPR43 Modulates YAP/TAZ via RhoA

  • Park, Bi-Oh;Kim, Seong Heon;Kim, Jong Hwan;Kim, Seon-Young;Park, Byoung Chul;Han, Sang-Bae;Park, Sung Goo;Kim, Jeong-Hoon;Kim, Sunhong
    • Molecules and Cells
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    • 제44권7호
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    • pp.458-467
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    • 2021
  • GPR43 (also known as FFAR2 or FFA2) is a G-protein-coupled receptor primarily expressed in immune cells, enteroendocrine cells and adipocytes that recognizes short-chain fatty acids, such as acetate, propionate, and butyrate, likely to be implicated in innate immunity and host energy homeostasis. Activated GPR43 suppresses the cAMP level and induces Ca2+ flux via coupling to Gαi and Gαq families, respectively. Additionally, GPR43 is reported to facilitate phosphorylation of ERK through G-protein-dependent pathways and interacts with β-arrestin 2 to inhibit NF-κB signaling. However, other G-protein-dependent and independent signaling pathways involving GPR43 remain to be established. Here, we have demonstrated that GPR43 augments Rho GTPase signaling. Acetate and a synthetic agonist effectively activated RhoA and stabilized YAP/TAZ transcriptional coactivators through interactions of GPR43 with Gαq/11 and Gα12/13. Acetate-induced nuclear accumulation of YAP was blocked by a GPR43-specific inverse agonist. The target genes induced by YAP/TAZ were further regulated by GPR43. Moreover, in THP-1-derived M1-like macrophage cells, the Rho-YAP/TAZ pathway was activated by acetate and a synthetic agonist. Our collective findings suggest that GPR43 acts as a mediator of the Rho-YAP/TAZ pathway.

공급사슬 위험평가 및 위험관리전략이 공급사슬 운영성과에 미치는 영향 (The Risk Assessment Effects of SCM and the Strategy of Risk Management on Supply Chain Performance)

  • 김동정;이영재
    • Journal of Information Technology Applications and Management
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    • 제21권4호
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    • pp.173-186
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    • 2014
  • This study outlines possible risk factors in the SCM of a company and correlates risk assessment, the strategy of risk management, and the supply chain performance. The data is surveyed from an international Korean company and is analyzed by the structure equation model of actual proof. The research model verifies the correlation between the risk assessment, the strategy of risk management, and the supply chain performance as dependent variables after the risk factors of the SCM are defined as independent variables. The research shows that there are consecutive links among the risk factors of the SCM, the risk assessment, and the strategy of risk management. The strategy of risk management was conclusively determined to have an effect on supply chain performance. Therefore, improving the supply chain performance of a company requires the constructive process for risk management based on a correlation between risk assessment and the strategy of risk management.

농산물 유통 정보화를 위한 공급사슬경영 프로세스 모델링 (A Supply Chain Management Process Modeling for an Agriculture Marketing Information System)

  • 명광식;박세권;강대원
    • 산업공학
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    • 제13권3호
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    • pp.358-377
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    • 2000
  • A supply chain is a network of facilities and distribution options that performs the functions of procurement of materials, transformation of these materials into intermediate and finished products, and the distribution of these finished products to customers. SCM(Supp1y Chain Management), by definition, encompasses all activities associated with moving goods, from the raw materials stage through to the end user. It includes source and procurement, production scheduling, order processing, inventory management, transportation, warehousing, and customer service. Importantly, it encompasses the information systems used to monitor these activities. In this paper, the present situation and problems of marketing process in Korean agricultural environments were reviewed through a systematic methodology, and then we proposed a new business process for solving these problems by appling a supply chain management. We expect this supply chain management system applied to agricultural marketing process can improve significantly the rationality and transparency of Korean agricultural marketing structure.

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N-Acetylglycine Side Chain is Critical for the Antimicrobial Activity of Xanthostatin

  • Kim, Si-Kwan;Ubukata, Makoto;Isono, Kiyoshi
    • Journal of Microbiology and Biotechnology
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    • 제13권6호
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    • pp.998-1000
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    • 2003
  • This study was carried out to elucidate the mode of bacteriostatic property of xanthostatin (XS), a novel depsipeptide antibiotic with an N-acetylglycine side chain and selective antimicrobial activity against Xanthomonas spp. Two biotransformed XSs were isolated by the treatment of XS with the cell lysate of Xanthomonas campestris pv. citri, a solvent partition, preparative TLC, and HPLC. Structure determination of those two biotransformed XSs demonstrated deletion of the N-acetylglycine side chain. Noteworthily, they showed no antimicrobial activity against Xanthomonas spp. This result suggests that the N-acetylglycine side chain plays a critical role in the antimicrobial activity of XS, and that the bacteriostatic property of XS is due to susceptibility of the ester bond between the hexadepsipeptide nucleus and the N-acetylglycine side chain to hydrolytic enzyme(s) produced by Xanthomonas spp.

공급사슬에 대한 개념적인 연구 (A Conceptual approach to supply chain)

  • 안웅
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2006년도 춘계공동학술대회 논문집
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    • pp.172-178
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    • 2006
  • 현대의 비즈니스 경영의 패러다임에서 가장 중요한 변화 중의 하나는 개별적인 비즈니스들이 단독으로 경영되는 자율적인 비즈니스 개체 보다 공급사슬이 더 높은 경쟁력을 갖고 있다는 사실이다. 비즈니스 경영은 네트워크 간의 경쟁시대에 진입하였으며, 개별 비즈니스의 궁극적인 성공은 비즈니스 관련자들의 복잡한 네트워크를 통합할 수 있는 경영능력에 좌우된다. 공급사슬은 최적해 접근방법에 의해서 종종 공학 또는 기술적인 관점에서 자주 논의 되어 졌다. 이 논문은 공급사슬에 대한 개념적인 연구이다. 공급사슬에 대한 개념적인 논의는 대부분 로지스틱스와 생산 및 운영관리 분야에서 수행되었다. 이 논문의 목적은 첫째로 그동안 연구되어진 공급사슬의 개념, 구조 및 통합을 이론적인 틀에서 분석 및 논의하는 것이다. 특히, 문헌에 나타난 공급사슬의 개념을 네 가지 특성으로 분류하여 제시하였으며, 공급사슬 구조에서는 민첩(agile), 린(lean) 및 leagility 공급사슬에 대해 다루었으며, 공급사슬 통합에서는 공급사슬통합자(supply chain integrator)에 대해 소개하였다. 둘째로, 공급사슬 문헌상에 처음으로 공리적인 공급사슬 모델을 제시하였다.

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Supply Chain Network 구성요소들의 양방향 선호도를 고려한 생산/분배 통합 모형 (Mutual Preferences based Design for Coordinated Production and Distribution on Supply Chain Network)

  • 정병희;최정일
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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    • pp.734-741
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    • 2002
  • The importance of efficient Supply Chain Management is increasing in accordance with recent industrial environment, such as globalization of business, complexity and diversity of company's management structure, and variety of customer's demand. In a rapidly changed environment of business, quick and efficient decision making is the important matter to the survival of the company. The purpose of this study supports decision making for efficient supply chain management. In this study, we consider simultaneously and mutually reflecting the preference of each constituent (Supplier, Manufacturing plant, Distribution center, Customer) on supply chain network, and decide company's strategic choice and coordinated production/distribution models of company. The Analytical Hierarchy Process is used for decision making of qualitative and quantitative elements. We use the results of AHP as inputs and propose mathematical models thru Mixed Integer Programming.

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