• Membrane Journal
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• v.29 no.3
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• pp.155-163
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• 2019

The anion exchange membrane using the blending polymer of poly(ether sulfone) and poly(phenylene sulfide sulfone) was prepared. It was confirmed by EDXS and FT-IR analysis that the prepared anion exchange membrane had the -N- as an anion exchange group. The ionic conductivity in 1 mol/L $H_2SO_4$ aqueous solution was measured. The ionic conductivity of the prepared anion exchange membrane was 0.015~0.083 S/cm, and had a high value compared with AFN and APS as a commercial anion exchange membrane. Permeabilities of the vanadium ions through the prepared anion exchange membrane were tested to evaluate the possibility as a separator in vanadium redox flow battery. Vanadium ion permeation rate in the prepared anion exchange membrane had a low value compared with Nafion 117 as a commercial cation exchange and AFN as a commercial anion exchange membrane.

• Journal of Internet Computing and Services
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• v.23 no.6
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• pp.59-69
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• 2022

For effective battlefield situation awareness and command resolution, information exchange without seams between systems is essential. However, since each system was developed independently for its own purposes, it is necessary to ensure interoperability between systems in order to effectively exchange information. In the case of our military, semantic interoperability is guaranteed by utilizing the common message format for data exchange. However, simply standardizing the data exchange format cannot sufficiently guarantee interoperability between systems. Currently, the U.S. and NATO are developing and utilizing information exchange models to achieve semantic interoperability further than guaranteeing a data exchange format. The information exchange models are the common vocabulary or reference model,which are used to ensure the exchange of information between systems at the content-meaning level. The information exchange models developed and utilized in the United States initially focused on exchanging information directly related to the battlefield situation, but it has developed into the universal form that can be used by whole government departments and related organizations. On the other hand, NATO focused on strictly expressing the concepts necessary to carry out joint military operations among the countries, and the scope of the models was also limited to the concepts related to command and control. In this paper, the background, purpose, and characteristics of the information exchange models developed and used in the United States and NATO were identified, and comparative analysis was performed. Through this, we intend to present implications when developing a Korean information exchange model in the future.

• Journal of Environmental Science International
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• v.16 no.8
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• pp.907-912
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• 2007

Ion exchange resin was used to remove silica ion at ultralow concentration. The effects of temperature, type of ion exchange resin and single/mixed-resin systems on removal efficiency were estimated. As temperature increased, the slope of concentration profile became stiff, and the equilibrium concentration was higher. In the single resin system, the removal of silica was continued up to 400 min, but the silica concentration was recovered to initial concentration after 400 min due to the effect of dissolved $CO_2$. In the mixed-resin system it took about 600 min to reach equilibrium. Because of faster cation exchange reaction than anion exchange reaction, the effect of $CO_2$ could be removed. Based on the experimental results carried out in the mixed-resin system, the selectivity coefficients of silica ion for each ion exchange resin were calculated at some specific temperatures. The temperature dependency of the selectivity coefficient was expressed by the equation of Kraus-Raridon type.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.4
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• pp.115-128
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• 2019

The study aims to investigate the pattern of relationships such as symmetric or asymmetric, between exchange rate and foreign direct investment in Bangladesh by applying Autoregressive Distributed Lagged (ARDL) and nonlinear ARDL. In this study, we employed quarterly data for the period of 1974Q1 to 2016Q4. Data were collected and aggregated from various sources namely, Bangladesh Economic Review published by Ministry of Finance and statistical yearbook published by Bangladesh Bureau of Statistics and an annual report published by Bangladesh Bank. The relationship between exchange rate and FDI inflows attract immense interest in the recent periods, especially for developing countries' perspective. The results of the study ascertain the long run relationship between FDI, exchange rate, monetary policy, and fiscal policy. Considering the asymmetric assumption, the findings from NARDL confirm the existence of a long-run asymmetric relationship in the empirical equation. In the long run, it is observed that positive change that is the appreciation of exchange rate against USD decrease FDI inflows and negative shocks results in grater inflows of FDI, however, the positive shocks produce higher intensity that negative shocks in Exchange rate. For directional causality, the coefficients of error correction term confirm long-run causality, in particular, bidirectional causality unveiled between FDI and exchange rate.

• Korea Trade Review
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• v.44 no.1
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• pp.17-30
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• 2019

This study is to investigate the effect of real exchange rate on bilateral trade balance between Korea and ASEAN 10 countries. Using quarterly data from 1991 to 2017 the paper analyzes whether or not the real depreciation of Korea's won could improve the trade balance in the short and long term. Based on Autoregressive Distributed Lag(ARDL) model, the empirical results show that trade balance, GDP, and real exchange rate are all cointegrated, representing the long-run relationship among variables. In the consideration of long-run relationship, the increases in ASEAN countries' GDP could have a negative impact and Korea's GDP positive impact on trade balance between Korea and ASEAN countries unexpectedly. For the main variable, the paper did not find the long-term effect of real exchange rate on the trade balance, for the short-term effect of the real exchange rate it was found that there exists the J-curve effect only in the case of Vietnam and Brunei. Therefore, these results imply that the intended policy concerning the exchange rate in the free-floating exchange rate system could be limited to improve the trade balance between Korea and ASEAN countries.

• The KIPS Transactions:PartC
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• v.10C no.5
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• pp.541-548
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• 2003

A fair exchange protocol enable two parties to exchange secrets with fairness, so that neither can gain any information advantage by quitting prematurely or otherwise misbehaving. Therefore a fair exchange is the most important for electronic transactions between untrusted parties. To design new fair exchange, after describing basic concepts, definitions and existing protocols and designing a non-interactive OT protocol using ELGamal's public key system, I will design new protocol to support fair exchange. In my designed new protocol, untrusted parties exchange secrets obliviously and verify that their received secrets are true by using transformed Zero Knowledge Interactive Proof extended to duplex. At this time, concerned two parties can't decrypt the other's ciphertext. .After all of the steps, two parties can do it. It is the most important to provide perfect fairness and anonymity to untrusted parties in this protocol.

• Polymer(Korea)
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• v.30 no.4
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• pp.291-297
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• 2006

In this study, adsorption properties of oxidized NO by plasma using aminated polyolefin-g-GMA hybrid anion exchange fibers were investigated. The maximum conversion of $NO_2$ by plasma was 49% at the conditions of 200 ppm NO, 10% $O_2$ and 30 L/min of flow rate. The adsorption content for N02 of hybrid anion exchange fibers increased with increasing the swelling ratio and the highest value was 1.5 g $H_2O/g$ IEF. The adsorption of $NO_2$ by hybrid anion exchange fibers were very fast until 10 min and reached its maximum value of 80% at 120 min. Ion exchange capacity of hybrid anion exchange fibers increased with increasing the swelling ratio and it showed the highest 0.6 mmol/g IEF values at L/D=5. The adsorption isotherm model for hybrid anion exchange fibers were closer to Freundlich than Langmuir adsorption isotherm model. It was shown that adsorption of the multi-molecular layer was dominant.

• Journal of the Korea Society of Computer and Information
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• v.27 no.12
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• pp.51-58
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• 2022

In this paper, we propose a decision tree-based machine learning model that leads to food exchange table renewal by classifying food groups through machine learning for existing food and food data found by web crawling. The food exchange table is the standard for food exchange intake when composing a diet such as diet and diet, as well as patients who need nutritional management. The food exchange table, which is the standard for the composition of the diet, takes a lot of manpower and time in the process of revision through the National Health and Nutrition Survey, making it difficult to quickly reflect food changes according to new foods or trends. Since the proposed technique classifies newly added foods based on the existing food group, it is possible to organize a rapid food exchange table reflecting the trend of food. As a result of classifying food into the proposed model in the study, the accuracy of the food group in the food exchange table was 97.45%, so this food classification model is expected to be highly utilized for the composition of a diet that suits your taste in hospitals and nursing homes.

• Membrane Journal
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• v.32 no.5
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• pp.336-347
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• 2022

Reverse electrodialysis (RED) is one of the promising eco-friendly renewable energy technologies which can generate electricity from the concentration difference between seawater and freshwater by using ion-exchange membranes as a diaphragm. The ion-exchange membrane is a key component that determines the performance of RED, and must satisfy requirements such as low electrical resistance, high permselectivity, excellent durability, and low manufacturing cost. In this study, pore-filled anion-exchange membranes were fabricated using porous polymer substrates having various thicknesses and porosity, and the effects of ion-exchange polymer composition and membrane thickness on the power generation performance of RED were investigated. When the electrical resistance of the ion-exchange membrane is sufficiently low, it can be confirmed that the RED power generation performance is mainly influenced by the apparent permselectivity of the membrane. In addition, it was confirmed that the apparent permselectivity of the membranes can be improved through IEC, crosslinking degree, membrane thickness, surface modification, etc., and the optimum condition must be found in consideration of the trade-off relationship with electrical resistance.

• Textile Coloration and Finishing
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• v.33 no.1
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• pp.24-30
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• 2021

In this study, PET containing 3% silver ion-exchange zeolite was mixed with cotton in a ratio of 6:4 to prepare a spun yarn to evaluate the tensile strength, absorption speed, absorption rate, antibacterial property, and the efficiency of deodorization. As a result, the following conclusions were obtained. First, it can be confirmed that silver ion exchange zeolite is evenly distributed inside and on the surface of the antimicrobial PET-SF through SEM. It was found that the tensile strength between the CVC sample mixed with silver ion zeolite PET and cotton and the normal cotton 100% sample was slightly lower in the CVC sample. Although the absorption speed and water absorption rate were measured to find out the moisture characteristics, it was confirmed that there was no significant difference. The contact angle was slightly larger in the antimicrobial CVC sample, but the time it took for the moisture to completely penetrate into the knit fabric was 0.85 seconds. In addition, it was found that out of the total mixing ratio, 40% of antibacterial PET was spun with regular cotton to produce yarn, which had an excellent bacteria reduction rate of 99.9% and a deodorization efficiency of 85%.