• 한국정밀공학회지
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• 제17권7호
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• pp.170-180
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• 2000

In this paper, to evaluate ease of exchange of subassembly considering module, it needs to analyze structure and function of subassembly, assembly and disassembly process. Exchange process of module can be divided into pre-process and in-process, and determination factors of exchange process are defined by analyzing characteristics of assembly and disassembly process. Based on the analysis of characteristics for structure and function of subassembly, influential factors of module can be proposed. Considered the interrelationship between determination factors of ease of exchange and influencing factors of module, ease of exchange can be evaluated.

• 상하수도학회지
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• 제29권1호
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• pp.65-75
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• 2015

In this study, cation and anion exchange process for performance evaluation was conducted. A pilot plant for the ultrpure water production was installed with the capacity of $25m^3/d$. The various production rate and regeneration of ion exchange rate were tested to investigate the design parameters. The test resulst was applied to calculate the operating costs. Changing the flow rate of the ion exchange capacity of the reproduction reviewed the cation exchange process as opposed to the design value is 120 to 164% efficiency, whereas both anion exchange process is 82 to 124% efficiency, respectively. This results can be applied for more large scale plant if the scale up parameters are consdiered. The ion exchange capacity of the application in accordance with the design value characteristic upon application equipment is expected to be needed. In this study, the performance of cation and anion exchange resin process was evaluated with pilot plant($25m^3/d$). The ion exchange capacity along with space velocity and regeneration volume was evaluated. In results, the operation results was compared with design parameters.

• 한국세라믹학회지
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• 제52권2호
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• pp.133-136
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• 2015

The outward diffusion of $Na^+$ ions in iron-bearing soda lime silicate glass via oxidation heat treatment before the ion exchange process is artificially induced in order to increase the amount of ions exchanged during the ion exchange process. The effect of the addition process is analyzed through measuring the bending strength, the weight change, and the inter-diffusion coefficient after the ion exchange process. The glass strength is increased when the outward diffusion of $Na^+$ ions via oxidation heat treatment before the ion exchange process is added. For the glass subjected to the additional process, the weight change and diffusion depth increase compared with the glass not subjected to the process. The interdiffusion coefficient is also slightly increased as a result of the additional process.

• 한국산학기술학회논문지
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• 제5권2호
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• pp.98-102
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• 2004

단일이온교환 프로세스를 도입하여 soda-lime-silicate 유리에 있어서의 이온교환 거동 및 물성변화를 관찰하였다. 온도 및 시간 변화에 따라 K/sup +/ 이온의 침투깊이, 이온교환량은 증가하였으며, 이에 비례하여 밀도, 굴절률도 증가하는 경향을 보였다 이온교환 과정에서 생성된 비가교 산소로 인하여 400nm에서 흡수 현상이 관찰되었으며, 열팽창계수는 구조의 치밀화와 이력현상에 영향을 받았다.

• 멤브레인
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• 제32권2호
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• pp.91-99
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• 2022

모든 인구 계층에 저렴한 비용으로 깨끗한 물의 수요를 충족시키는 것은 해결해야 할 세계적인 문제이다. 막 분리 공정을 통한 해수 및 기수의 탈염은 효율이 높고 확립된 방법이다. 그러나 막 분리 공정은 막 오염, 제거된 오염물의 처리, 그리고 자본집약적 공정이라는 본질적인 문제가 있다. 전기투석은 전위차가 구동력인 막 기반 분리 공정이다. 전기투석막의 장점은 뛰어난 효율과 저렴한 운영 비용이다. 전기투석공정에서 사용되는 이온교환막은 장기간 효율을 잃지 않기 위해 내화학성과 내열성, 그리고 기계적 안정성이 필요하다. 이 때, 전기투석막의 이온교환용량은 이온교환막의 전도도에 따라 크게 달라진다. 본 리뷰에서는 이온 전도도과 안정성을 향상시키기 위한 양이온 교환막과 음이온 교환막의 개조를 중점적으로 논의하였다.

• 반도체디스플레이기술학회지
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• 제16권3호
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• pp.106-110
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• 2017

Due to the plasma applied from the outside, which acts as an etchant during the etching process, considerable heat is transferred to the wafer and a separate cooling process is performed to effectively remove the heat after the process. In this case, a direct cooling method using a refrigerant is suitable for cooling through effective heat exchange. The direct cooling method using the refrigerant using the latent heat exchange is superior to the cooling method using the sensible heat exchange. Therefore, in this paper, AMESim is used to design a direct refrigerant cooling system using latent heat exchange simulator was built.The constructed simulator is reliable compared with the actual experimental results. It is expected that this simulator will help to design and search for optimal process conditions.

• 반도체디스플레이기술학회지
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• 제17권3호
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• pp.100-103
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• 2018

Due to the plasma applied from the outside, which acts as an etchant during the etching process, considerable heat is transferred to the wafer and a separate cooling process is performed to effectively remove the heat after the process. In this case, a direct cooling method using a refrigerant is suitable for cooling through effective heat exchange. The direct cooling method using the refrigerant using the latent heat exchange is superior to the cooling method using the sensible heat exchange. Therefore, in this paper, AMESim is used to design a direct refrigerant cooling system using latent heat exchange simulator was built.The constructed simulator is reliable compared with the actual experimental results. It is expected that this simulator will help to design and search for optimal process conditions.

• East Asian mathematical journal
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• 제37권1호
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• pp.79-85
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• 2021

In this paper, we investigate the valuation of vulnerable exchange option that has credit risk of option issuer. The reduced-form model is used to model credit risk. We assume that credit event is determined by the jump of the counting process with stochastic intensity, which follows the mean reverting process. We propose a simple approach to derive the closed-form pricing formula of vulnerable exchange option under the reduced-form model and provide the pricing formula as the standard normal cumulative function.

• 한국항만학회지
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• 제14권1호
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• pp.77-86
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• 2000

The planning process of complex projects in oceanic architectural engineering is characterized by the cooperation of many involved specialists and by a high degree of information exchange. In order to improve the quality of the structural design of oceanic buildings, information of different involved partners in the planning process has to be integrated. This paper aims to introduce a concept of the integrated structural design for the floating-type oceanic building using STEP(Standard for the Exchange of Product Model Data). STEP(ISO 10303) is an international standard for the computer-interpretable representation and exchange of product data and it provides a consistent data exchange format and application interfaces between different application systems. In this paper, the structural design process and information of oceanic buildings is analyzed and product models are preposed fir the exchange of the structural design information between superstructure and floating structure. The entities for calculating wind loads, metacenter and restoring forces are represented by Express. As a case study a floating hotel is applicated to describe the STEP physical file.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2004년도 International Conference Global Environmental Problems and their Health Consequences
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• pp.155-159
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• 2004

We synthesized ion exchange resin that can remove $NO_3\;^-$ selectively rather than $SO_4\;^{2-}$. Ion exchange property of the synthesized ion exchange resin occurred like the following process, $NO_3\;^-$ > $SO_4\;^{2-}$, the efficiency of functional group to remove $NO_3\;^-$ occurred in the process of $NPr_3$ > $NBu_3$ > $NEt_3$ > $NMe_3$ > $NPe_3$ > $N(EtOH)_3$, and the efficiency of functional group to remove $SO_4\;^{2-}$ occurred in the process of $NMe_3$ > $NEt_3$ > $NPr_3$ > $NBu_3$ > $NPe_3$.