• Membrane Journal
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• v.17 no.2
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• pp.146-160
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• 2007

A parametric study on pervaporation-facilitated esterification was performed by using a practical model based on non-perfect separation through membrane which is not perfectly permselective to water. Thus, membrane selectivity as well as membrane capability to remove water should be taken into account in establishing the simulation model to explain how the membrane separation influence the esterification reaction process. It was shown by simulation that in the reaction systems with non-perfect separation, the permeation of reactants which are acid or/and alcohol retards the reaction by inducing the backward reaction so that reaction conversion curve is located between a reaction system coupled with pervaporation process having a perfect permselectivity to water and a reaction system without pervaporation process. The volume change of reaction system occurs as a result of the permeation through the membrane. The reaction volume change which can be characterized by the reaction ratio of $r_{\Psi}\;to\;r_{{\Psi}=1}$ affects reaction kinetics by concentrating reactants and products, respectively, with different extent with time; reactant-concentrating effect is dominant during the initial stage of reaction, resulting in facilitating the reaction, and then product-concentrating effect is exerted more on reaction, causing to slow down the reaction. When pervaporative dehydration is applied to the reaction system plays an important role in the reaction as well. The effect of timing to impose pervaporation on reaction system affected the reaction kinetics in terms of reaction rate and reaction conversion. A relationship was derived to explain membrane unit capacity and reaction parameters that will be used as a design tool to determine membrane unit capacity at a given reaction conditions or reaction parameters at a membrane unit capacity.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.419-426
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• 1999

In this study, the reaction rate constant, activation energy, total crosslinking density, elastic constant, cure properties ($t_5,\;t_{90}$), modulus, and abrasion resistance of rubber compounds were investigated as a function of cure temperatures, cure systems and reinforcing filler loadings. Reaction rate constants showed strong dependence on thc carbon black loading, cure temperature and cure system, and increased sharply with increasing the reaction temperatures. The lowest activation energy was obtained in the efficient cure (EC) system which corresponds to the high level of sulfur to accelerator ratio, and the activation energy was decreased with decreasing the carbon black loadings. The change of carbon black loadings directly affects the modulus and abrasion resistance, but the change of cure system showed various effects on the rubber compounds. Increased carbon black loadings showed the high modulus, improved abrasion resistance and short scorch time but decrease in crosslinking density and elastic constant. Higher crosslinking density and elastic constant were shown in the EC cure system regardless of carbon black loadings, but scorch timc ($t_5$) was not affected by the change of the ratio of sulfur to accelerator. Rapid optimum cure time ($t_{90}$) were showen in the EC cure system. Also, the equivalent cure curve coefficient of rubber compound was 0.96 for conventional cure (CC) system, and 0.94 for semi-efficient cure (SEC) and EC system regardless carbon black loadings. As regarding the abrasion resistance, wear volume showed the logarithmic increase for the loaded weight.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.2
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• pp.9-14
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• 2009

This study was conducted to develop a electronic circuit of primary color reaction for urine analyzer for measuring color response of urine strip. A primary color reaction system is equipped with the computer, electronic circuit, tray, detecting assembly and software. The determination of coefficient($R^2$) between reagent and color sensor were 0.9801(R), 0.9868(G) and 0.9837(B). To evaluate the system verification, we measured the primary color reaction of erythrocytes, Bilirubin, Urobilinogen, Ketones and Protein. We concluded that it is possible to use the developed the primary color reaction system for urine analyzer using u-health.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.129-146
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• 2010

System response times(SRTs) are getting important while increasing the function of system. In the past, most research studied SRTs on situation of computer usage. There are lacking the research on simple domain. This study focuses on behavioral and emotional effect on situation of cell phone usage(experience 1; independent variables: degree of SRTs, dependent variables: behavioral and emotional evaluation). And this study investigates the behavioral and emotional effect in same SRTs on different situation(experience 2; independent variables: degree of SRTs, usage mode, dependent variables: behavioral and emotional evaluation, stress, mental strain). The result indicated that long SRTs increased problem solving time and negative emotion. User evaluated the system differently according to usage mode after they performed the same task. In other word, if user had a strong goal, then they felt more negative emotion and mental effort than the user don't have a strong goal. In the goal mode group, it was important there are being of delay or not. This study demonstrated that SRTs and usage mode influence user's emotion and behavior performance in same task.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10d
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• pp.613-618
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• 2007

현재 하나의 TV에 연결할 수 있는 수많은 기기들이 개발, 판매되고 있다. 이렇게 연결하는 방법 중 현재 많이 사용하고 있는 방법 중에 하나인 HDMI의 경우에 HDMI-CEC라는 기능을 도입해서 연결된 각각의 기기를 따로따로 컨트를 하지 않고 하나의 리모컨으로 적용하는 방안을 제시하고 있다. 현재 가정에서 사용하는 DVD-Recorder에 HDMI-CEC 기능을 대응하여, 사용자가 원하는 기능을 여러 개의 기기를 직접 제어하는 것이 아니라, 단 하나의 키 동작으로 여러 개의 기기를 동시에 제어하는 시스템을 설계한다면 사용자에게 많은 편의를 줄 수가 있다. 그러나, 이러한 시스템을 설계했을 경우에 사용자가 원하는 동작을 정확히 안 하는 문제, 반응 속도가 너무 느려서 사용자가 동작을 안 하는 것으로 착각하게 만드는 문제와 HDMI-CEC의 Spec에서는 제시하고 있지 않으나 사용자의 편의물 위해서 지원해야 하는 경우가 있을 수 있다. 이 논문에서는 HDMI-CEC와 PDC의 spec에 대한 설명을 하고, HDMI-CEC를 적용한 시스템에 대한 설계를 한다. 그리고, 그 시스템에서 발견된 문제 중 정확한 동작을 하지 않는 TV가 꺼져있는 OnTouchPlay의 경우의 대한 처리와, 반응 속도가 느린 경우인 시스템을 부팅하는 경우의 반응시간을 줄이는 방안, 그리고 HDMI-CEC의 spec에는 없으나 사용자의 편의를 위해서 지원해야 하는 기능들에 대해 논한다.

• Information and Communications Magazine
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• v.34 no.5
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• pp.76-82
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• 2017

본고에서는 수요반응을 위한 스마트가전과 서비스사업자 간 인터페이스의 요구사항을 서술한다. 전체 시스템 구조는 NIST Special Publication 1108R2를 참조하되 보안에 대해서는 다루지 않는다. 또한 향후 수용가 중심의 수요반응 보급 및 확산을 위한 발전방향에 대해 알아본다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.6
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• pp.881-887
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• 2018

Various services using smart phones are being provided, and a variety of services are also provided in payment fields. Since the mobile payment services is closely related to the monetary part, various characteristics of the mobile system have a close relation with use trust. In this study, accessibility, compatibility, and security were selected as important factors in the mobile payment systems. We will examine how these system factors affect users' cognitive trust, emotional responses such as positive emotions and satisfaction. We surveyed users of mobile payment systems to achieve our research purposes. SPSS 23 and SmartPLS 2.0 were used for the analysis. The results showed that all system factors influenced cognitive trust and emotional response. However, positive emotions did not affect satisfaction. However, when we examine the relationship between emotional responses, positive emotions do not affect satisfaction.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.2
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• pp.144-150
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• 2013

Hybrid ceramic membrane (HCM) processes that combined ozonation with a ceramic membrane (CM) or a reactive ceramic membrane (RM), an iron oxide nanoparticles (IONs) incorporated-CM were investigated for membrane fouling control. Alumina disc type microfiltration and ultrafiltration membranes doped with IONs by sintering method were tested under varying mass fraction of IONs. Scanning electron microscope (SEM) images showed that IONs were well-doped on the CM surface and doped IONs were approximately 50 nm in size. Change in the pure water permeability of RM was negligible compared to that of CM. These results indicate that IONs incorporation onto CM had little effect on CM performance in terms of the flux. Natural organic matter (NOM) fouling and fouling recovery patterns during HCM processes confirmed that the RM-ozonation process enhanced the destruction of NOM and reduced the extent of fouling more than the CM-ozonation process by hydroxyl radical formation in the presence of IONs on RM. In addition, analyses of NOM in the feed water and the permeate showed that the efficiency of membrane fouling control results from the NOM degradation during HCM processes; leading to removal and transformation of relatively high contents of aromatic, high molecular weight and hydrophobic NOM fractions.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.5
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• pp.797-804
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• 2017

A social network is a typical social science environment with both network and iteration characteristics. This research presents a reaction analysis model of how each node responds to social networks when given input such as promotions or incentives. In addition, the setting value of a specific node is changed while examining the response of each node. And we try to understand the reactions of the nodes involved. The reaction analysis model is constructed by applying various techniques such as unidirectional, fuzzy set, weighting, and cyclic feedback, so it can accommodate the complicated environment of practice. Finally, the implementation model is implemented using Vensim rather than NetLogo because it requires repetitive input, change of setting value in real time, and analysis of association between nodes.

• Proceedings of the Korean Society of Computer Information Conference
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• 2014.07a
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• pp.189-190
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• 2014

현재 명동성당을 제외한 나머지 성당에 성물 방에서는 성물 판매 및 입고 장부, 수입 지출내역을 수기 식으로 운영 하고 있다. 따라서 본 시스템은 성당 성물 방에 적합한 판매재고관리 시스템을 개발하는데 그 목적이 있다. 본 개발 시스템은 성당에서의 성물 입고 및 판매, 재고 관리에 목표를 두고 주로 통계 및 재고관리와 반응 형 웹에 초점을 맞추어 개발되었다. 재고 관리를 위한 입고현황, 판매현황, 제품현황과 거래처 관리를 위한 거래처 현황, 거래처 거래현황을 주목적으로 하였다. 재고관리의 경우 재고가 적정재고 보다 수량이 적으면 알림을 띄워 알려주고 재고가 없으면 판매 할 수 없도록 하였다. 시스템을 개발함으로서 보다 효과적인 재고관리에 주력하였고, 입고, 판매, 수입 지출 내역을 장부로 직접 작성하면서 생기는 오류에 관련된 문제를 해소하도록 하였다. 스마트 폰에서 볼 수 있는 App을 별도로 개발 하지 않고 하나의 시스템으로 운영되어 유지보수 및 관리를 손쉽게 하기 위하여 반응 형 웹을 적용하여 스마트폰, 데스크 탑, 태블릿 PC등 각각 해상도가 다른 화면에서 동일한 정보를 제공하도록 하였다.