• Title/Summary/Keyword: Key chain

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A Study on Accelerating Marine Equipments Industry for Enforcing Competitiveness of the Offshore Plants Industry (해양플랜트산업 경쟁력 강화를 위한 조선기자재산업 고도화에 관한 연구)

  • HA, Chang-Seung;JUNG, Dae-Hyun
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.5
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    • pp.1369-1379
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    • 2015
  • This study attempted an AHP analysis through interview with experts in the industries and questionnaire survey on recognition of organization members and future strategic development direction in order to upgrade shipbuilding equipment industries to marine plant equipment industries. Key research results are as follows. First, according to analysis on relative priority between three aspects on acceleration of shipbuilding equipment industries, importance was shown in the order of acceleration of internal competence, acceleration of manufacturing technology, and acceleration of supply chain, which means that the aspect on acceleration of internal competence had relatively higher importance. Second, as for relative importance of detailed item evaluation per respective aspect, it was found that development of core competencies was high from the aspect on acceleration of internal competence, higher value-addition was high from the aspect on acceleration of manufacturing technology, and IT infrastructure construction was high from the aspect on acceleration of supply chain.

Effect of Activation Energy and Crystallization Kinetics of Polyethylenes on the Stability of Film Casting Processes

  • Lee, Joo-Sung;Cho, Joon-Hee
    • Korea-Australia Rheology Journal
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    • v.21 no.2
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    • pp.135-141
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    • 2009
  • Effect of activation energy and crystallization kinetics of polyethylenes (PEs) on the dynamics and stability has been investigated by changing rheological properties and crystallization rate in film casting process. The effect of changes of these properties has been shown using a typical example of short-chain branching (SCB) in linear polyethylenes. SCBs in linear polymers generally lead to the increase of the flow activation energy, and to the decrease of the crystallization rate, making polymer viscosity lower in the case of equivalent molecular weight. In general, the increment of the crystallinity of polymers under partially crystallized state helps to enhance the process stability by increasing tension, and lower fluid viscoelasticity possesses the stabilizing effect for linear polymers. It has been found that the fluid viscoelasticity plays a key role in the control of process stability than crystallization kinetics which critically depends on the cooling to stabilize the film casting process of short-chain branched polymers operated under the low aspect ratio condition.

A Development of Reverse Supply Chain Simulation Model Considering a Recycling (재활용을 고려한 역공급사슬 시뮬레이션 모델 개발)

  • Lim, Seok-Jin;Park, Byung-Tae
    • Journal of the Korea Safety Management & Science
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    • v.11 no.4
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    • pp.193-199
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    • 2009
  • Recently, an industrial production-distribution planning problem has been widely investigated in Supply Chain Management(SCM). One of the key issues in the current SCM research area is reverse logistics network. This study have developed a simulation model for the reverse logistics network. The simulation model analysis reverse logistics network issues such as inventory policy, manufacturing policy, transportation mode, warehouse assignment, supplier assignment. Computational experiments using commercial simulation tool ARENA show that the real problems. The model can be used to decide an appropriate production-distribution planning problem in the research area.

Multiplex Reverse Transcription Polymerase Chain Reaction Assay for Simultaneous Detection of Five Cucurbit-infecting Viruses.

  • Lee, Su-Heon;Kim, Sang-Mok;Kim, Woo-Chang;Lee, Key-Woon
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 2003.10a
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    • pp.150.1-150
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    • 2003
  • A single-step multiplex reverse transcription polymerase chain reaction (RT-PCR) assay was developed for the simultaneous detection of five cucurbit-infecting viruses: cucumber mosaic virus (CMV), watermelon mosaic virus 2 (WMV2), zucchini yellow mosaic virus (ZYMV), cucumber green mottle mosaic virus (CGMMV), and kyuri green mottle mosaic virus (KGMMV). The multiplex RT-PCR provides a simple and rapid method for detecting various viruses in cucurbit plants, which will help diagnose many cucurbit plants at a time.

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The State-of-the-Art Review on the Information Technologies for Manufacturing Toward Digital Shipbuilding (디지털 선박생산화를 위한 생산정보기술)

  • 이경호;장윤석
    • Journal of Ocean Engineering and Technology
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    • v.17 no.4
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    • pp.81-85
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    • 2003
  • The industry has undergone a significant change over the last decade: digital business has become a strategy to survive; the extended enterprise is being implemented; parts are made where conditions are most favourable; non-core activities are out-sourced; advanced manufacturing systems and information technologies are introduced to improve manufacturing performance. Suppliers and distributors become part of the supply chain and they all comprise an integrated international co-operative network to provide manufactured goods and support services for a world market just in time, at low prices and with quality surpassing customers' expectations. In this paper, we review various state-of-the-art information technologies for the shipbuilding industry. The successful introduction and implementation of those technologies will be the key enabler for e-transformation in the shipbuilding industry.

Effectiveness of an Exponentially Smoothed Ordering Policy as Compared with Kanban System

  • Tamura, Takayoshi;Dhakar, Tej S.;Ohno, Katsuhisa
    • Journal of Korean Institute of Industrial Engineers
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    • v.34 no.1
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    • pp.1-12
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    • 2008
  • The Kanban system in Just-In-Time (JIT) production is very effective in reducing the inventories when consumption rate of the final product is relatively stable. When large fluctuations exist in the consumption rate, a new production ordering policy in which the production order quantity is determined by smoothing the demands exponentially is more suitable. This new ordering policy has not been investigated sufficiently. In this research, a multi-stage production and inventory system with stock points for materials and finished items located at each stage is considered. Approximations of average inventories at each stage in the system are derived theoretically. Numerical simulations are carried out to assess the accuracy of approximations and to evaluate the effectiveness of the new ordering policy as compared with the Kanban system. As a result, it is shown that the new ordering policy can achieve significantly lower inventory costs than the original Kanban system. The new ordering policy thus emerges as a key concept for an effective supply chain management.

Nanotechnology in elastomers- Myth or reality

  • Shanmugharaj, A.M.;Ryu, Sung-Hun
    • Rubber Technology
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    • v.12 no.1
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    • pp.1-7
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    • 2011
  • Nanotechnology is the fast becoming key technology of the $21^{st}$ century. Due to its fascinating size-dependent properties, it has gained significant important in various sectors. Myths are being formed on the proverbal nanotechnology market, but the reality is the nanotechnology is not a market but a value chain. The chain comprises of - nanomaterials (nanoparticles) and nanointermediates (coatings, compounds, smart fabrics). Elastomer based nanocomposites reinforced with low volume fraction of nanofillers is the first generation nanotechnology products and it has attracted great interest due to their fascinating properties. The incorporation of nanofillers such as nanolayered silicates, carbon nanotubes, nanofibers, metal oxides or silica nanoparticles into elastomers improves significantly their mechanical, thermal, barrier properties, flame retardency etc., Extremely small particle size, high aspect ratio and large interface area yield an excellent improvement of the properties in a wide variety of the materials. Uniform dispersion of the nanofillers is a general prerequisite for achieving desired properties. In this paper, current developments in the area of elastomer based nanocomposites reinforced with layered silicate and carbon nanotube fillers are highlighted.

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Synthesis, Characterization, and Properties of Ethoxylated Azo Dyes

  • Shen, Kaihua;Choi, Dong Hoon;Li, Zongshi
    • Fibers and Polymers
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    • v.4 no.1
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    • pp.32-37
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    • 2003
  • The nonionic surfactant properties of ethoxylated azo dyes, such ai cloud point and surface tension have been investigated. The synthesized ethoxylated azo dyes could dye polyester fabric without any special pre-treatment. When the average number of ethylene oxide (EO) in the ethoxylated azo dye reached 6, its fixation could exceed $90^{\circ}C$ from the thermosol dyeing process. The average degree of condensation of ethylene glycol in the chain was interrelated with the dyeing results and did not affect on the maximum absorption wavelength (λmax) of the polyoxyethylene dye. When the average length of polyoxyethylene chain decreased, the molecular weight of dyes became smaller and the fixation of dyes was improved.

The Synthesis of Chlorin-based Photosensitizers for using in Photodynamics Therapy by Modification of Methyl Pyropheophorbide-a

  • Wang, Jin-Jun;Han, Guang-Fan;Shim, Young-Key
    • Journal of Photoscience
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    • v.8 no.2
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    • pp.75-77
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    • 2001
  • The Grignard reaction of methyl pyropheophorbide-a (MPP-a) was performed to introduce lengthy alkyl chain for improving lipophilicity. After the introduction of alkyl chain to the both of carbonyls, peripheral aldehyde and cyclopentanone, the obtained diol 3 was subjected to dehydration to give monodehydrate product 4 selectively. The Qy band of prepared compounds were affected by the substituents on the Qy axis (N$\sub$21/-N$\sub$23/).

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A Study on the Criteria to Decide the Number of Aircrafts Considering Operational Characteristics (항공기 운용 특성을 고려한 적정 운용 대수 산정 기준 연구)

  • Son, Young-Su;Kim, Seong-Woo;Yoon, Bong-Kyoo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.1
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    • pp.41-49
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    • 2014
  • In this paper, we consider a method to access the number of aircraft requirement which is a strategic variable in national security. This problem becomes more important considering the F-X and KF-X project in ROKAF. Traditionally, ATO(Air Tasking Order) and fighting power index have been used to evaluate the number of aircrafts required in ROKAF. However, those methods considers static aspect of aircraft requirement. This paper deals with a model to accommodate dynamic feature of aircraft requirement using absorbing Markov chain. In conclusion, we suggest a dynamic model to evaluate the number of aircrafts required with key decision variables such as destroying rate, failure rate and repair rate.