• Membrane Journal
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• v.27 no.1
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• pp.84-91
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• 2017

In this study, heterogeneous ion exchange membranes were prepared by mixing cation or anion exchange resins and commercial polyvinylidene fluoride (PVDF) for MCDI process. The mixing ratios of PVDF and ion exchange resins were 1 : 1, 1.4 : 1, 2 : 1, and 3 : 1. We characterized SEM, water content, ion exchange capacity, methanol permeability, and ion conductivity. In the viewpoint of membrane characterization, the blending ratio of 2 : 1 showed the best. For the blending ratio of 2 : 1, heterogeneous cation exchange membrane showed the water content 34%, ion exchange capacity 1.54 meq/g, ion conductivity 0.019 S/cm, and methanol permeability $2.28{\times}10^{-7}{\sim}8.86{\times}10^{-7}cm^2/s$ while In the case of heterogeneous anion exchange membrane, the result showed 37%, 2.18 meq/g, and 0.034 S/cm and $1.46{\times}10^{-7}{\sim}8.66{\times}10^{-7}cm^2/s$.

• Membrane and Water Treatment
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• v.8 no.3
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• pp.259-277
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• 2017

Adsorption is a widely used technique for the removal of dyes from wastewaters by variety of adsorbents. In this work, the main focus is on the potential assessment of anion exchange membrane for the removal of different dyes using batch system and investigation of experimental data by applying various kinetic and thermodynamic models. The removal of anionic dyes i.e., Eosin-B, Eriochrome Black-T and Congo Red by anion exchange membrane BII from aqueous solution was carried out and effect of various parameters such as contact time, membrane dosage, temperature and ionic strength on the percentage removal of anionic dyes was studied. The experimental data was assessed by kinetic models namely pseudo-first-order, pseudo-second-order, Elovich liquid film diffusion, Bangham and the modified Freundlich models equation have been used to analyze the experimental data. These results indicate that the adsorption of these anionic dyes on BII follows pseudo-second-order kinetics with maximum values of regression coefficient (0.992-0.998) for all the systems. The adsorption of dyes was more suitable to be controlled by a liquid film diffusion mechanism. The adsorptive removal of dye Eosin-B and Eriochrome Black-T were decreased with temperature and thermodynamic parameters such as free energy (${\Delta}G^o$), enthalpy (${\Delta}H^o$) and entropy (${\Delta}S^o$) for adsorption of dyes on membrane BII were calculated at 298 K, 308 K and 318 K. The values of enthalpy and entropy were negative for EB and EBT representing that the adsorption of these dyes on BII is physiosorptive and exothermic in nature. Whereas the positive values of enthalpy and entropy for CR adsorption on BII, indicating that its adsorption is endothermic and spontaneous in nature. It is evident from this study that anion exchange membrane has shown good potential for the removal of dyes from aqueous solution and it can be used as adsorbent for dues removal on commercial levels.

• Membrane Journal
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• v.26 no.3
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• pp.229-237
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• 2016

We prepared heterogeneous ion exchange membranes (hetero-IEMs) for the application of membrane capacitive deionization (MCDI). Hetero-IEMs were fabricated by compressing the mixture of ion exchange resin powders and liner low density polyethylene (LLDPE). Characterization and MCDI desalination experiments were carried for the fabricated membranes. Electrical resistance of membrane decreased and water content increased with increasing the resin content in the hetero-IEMs. However, transport number indicating permselectivity of membrane was similar with that of commercial homogenesous ion exchange membrane. The results of MCDI desalination experiments showed that the adsorption amount for hetero-IEM was about 90% of that of homogeneous membrane due to the high electrical resistance of hetero-IEM. Although desalination performance of hetero-IEM decreased compared with homogeneous membrane, it was thought to be applicable to MCDI because of simple preparation and low price.

• Journal of the Korean Society for information Management
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• v.24 no.1 s.63
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• pp.121-145
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• 2007

This study aims to identify copyright issues regarding the knowledge content currently circulated through knowledge exchange markets in the Republic of Korea. The content providers of knowledge exchange markets comprise government & public institutions, full-text database companies, publishers and individuals. It is worth noting that commercial trade of copyrighted content or material among academic journals, database companies and knowledge exchange markets essentially exclude individual authors who are the actual copyright holders. In principle, the original author owns the copyright whether it has an explicit notice or not. Unless the author/owner officially agrees to transfer the copyright including the right for so-called "derivative works", content-making based or derived from the copyrighted material, digitalization of the copyrighted work as well as its registration on full-text database and circulation through knowledge markets are illegal.

• Journal of Magnetics
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• v.20 no.4
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• pp.336-341
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• 2015

MnBi alloys were fabricated by arc melting and annealing at 573 K. The heat treatment enhanced the content of the low-temperature phase (LTP) of MnBi up to 83 wt%. The Bi-excess assisted LTP MnBi alloys were used in the hybridization with the Nd-Fe-B commercial Magnequench ribbons to form the hybrid magnets (100-x)NdFeB/xMnBi, x = 20, 30, 40, 50, and 80 wt%. The as-milled powder mixtures of Nd-Fe-B and MnBi were aligned in a magnetic field of 18 kOe and warm-compacted to anisotropic and dense bulk magnets at 573 K by 2,000 psi for 10 min. The magnetic ordering of two hard phase components strengthened by the exchange coupling enhanced the Curie temperature ($T_c$) of the magnet in comparison to that of the powder mixture sample. The prepared hybrid magnets were highly anisotropic with the ratio $M_r/M_s$ > 0.8. The exchange coupling was high, and the coercivity $_iH_c$ of the magnets was ~11-13 kOe. The maximum value of the energy product $(BH)_{max}$ was 8.4 MGOe for the magnet with x = 30%. The preparation of MnBi alloys and hybrid magnets are discussed in details.

• The Journal of Asian Finance, Economics and Business
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• v.10 no.1
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• pp.9-17
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• 2023

The study attempted to answer the questions related to the expected effects of supply chain management variables which include: Partnership with Suppliers (PS), Relationships with Customers (RC), Quality of Information Exchange (QIE), and Postponement (P), as independent variables, total quality management (TQM) as a dependents variable, and just in time (JIT) as a mediator variable. The study relies on the descriptive approach by conducting an empirical study on commercial companies in Riyadh Governorate in the Kingdom of Saudi Arabia. Through the methods of descriptive and analytical statistics represented in exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and structural equation modeling (SEM)), using the AMOS and SPSS programs, the results of the applied study indicated that: There is an effect of supply chain management variables (quality of information exchange, Postponement) on just in time (JIT), there is no effect of the supply chain variables (relationship with customers, partnership with suppliers) on just in time (JIT), there is an indirect effect of the quality of information exchange, Postponement, partnership with suppliers, the relationship with customers on total quality management (TQM), relationship with customers affect on total quality management (TQM) indirectly, just in time (JIT) does not affect total quality management (TQM)

• International Journal of CAD/CAM
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• v.5 no.1
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• pp.39-47
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• 2005

Different CAx systems are being utilized throughout the product lifecycle due to the practical reasons in the supply chain and design processes. One of the major problems facing enterprises of today is how to share and exchange data among heterogeneous applications. Since different software applications use different terminologies, it is difficult to share and exchange the product data with internal and external partners. This paper presents a method to enhance the CAD model interoperability based on feature ontology. The feature ontology has been constructed based on the feature definition of modeling commands of CAD systems. A method for integration of semantic data has been proposed, implemented, and tested with two commercial CAD systems.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.288-291
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• 2005

This paper is aimed at presenting a proton exchange membrane (PEM) fuel cell stack. The fuel cell electrical output voltage and current (V-I) characteristic is described for the first time by a simplified closed form suitable. The characteristics obtained from the simulation are compared with the experimental results on a Ballard commercial fuel cell stack as well as to the manufacturer given data.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.12
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• pp.119-131
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• 2011

To be integrated into the IEC 61970-based K-Grid, application of open communication protocol and sub-system modeling to major nodes is needed. In this paper, a module which links load nodes in customers to CIM based on psXML/oBIX, one of open protocols, was developed and data modeling and communication protocols of IEC 61850-7-42 based DER and ESS which apply the module to the customers who have DER and ESS were designed. Also the XML-based distributed database middleware was designed. The proposed modeling and protocols were applied to the building in which commercial DER products and the effectiveness of the proposed data modeling and the communication protocol were evaluated.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.1398-1401
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• 2004

In case the problem came into the headlight composed of a bulb, lens and reflecting mirror, it has a sealed-beam type which must exchange all and semi-sealed beam type which can exchange only bulb. The headlight of train must be used at the time of going into tunnel and atmospheric phenomena such as heavy snow, rain and foggy as a rule, also it can be used with whistle blow when the dangerous article appears. In this study, general technical specification to improve headlight of the KTX and G7 high speed train is described throughout investigation technique of the industrialized country and headlight specification of train which is on commercial service.