• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.5
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• pp.1747-1753
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• 2010

In this study, a comparative study was performed to predict the vapor-liquid equilibria with maximum azeotropic pressure for ethanol-benzene binary system between an equation of state model and a liquid activity coefficient model. Peng-Robinson equation of state model with a Panatiotopoulos mixing rules (PRP) was used and NRTL liquid activity coefficient model proposed by Renon was selected. The PRP model, even though it has only two binary adjustable parameters, was not inferior to the NRTL model to predict vapor-liquid equilibria for low pressure region of ethanol-benzene system and showed a better prediction capability for high pressure region of ethanol-benzene system than the NRTL model with three binary interaction parameters.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.695-706
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• 2016

The present study sought to shed light on specific designs and strategies by investigating the impact that team project-based learning approach using Naver Band had on learning outcomes specifically, on satisfaction and achievement. Variables of perceived usefulness and perceived ease of use were chosen as critical predictors of the learning outcomes. 70 undergraduate students were divided into 18 groups and instructed to work on a team project using Naver Band for 6 weeks. Data analysis was completed using descriptive statistic analysis, correlation analysis, hierarchical regression analysis. Also, descriptions of Band from team reflection journal were analyzed. The major results of the study are as follows: first, perceived usefulness was the significant predictor of satisfaction and achievement. Second, 5 functions were revealed as strengths about Band.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.259-265
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• 2005

Binary isothermal vapor-liquid equilibrium(VLE) data were measured for water+n-methylformamide(NMF), benzene+NMF and toluene+NMF systems by using headspace gas chromatography(HSGC) at 353.15K. Additionally, the ternary liquid-liquid Equilibrium(LLE) data were determined by measuring of tie-line for the systems of NMF+benzene+n-heptane and NMF+toluene+n-heptane at 298.15 K. The measured isothermal binary VLE data have no azeotropes and were correlated well with $g^E$ model equations of Margules, van Laar, Wilson, NRTL and UNIQUAC. The experimental ternary tie line data were also correlated well with NRTL and UNIQUAC models. Besides their accuracy was analyzed by Hirata-Fujita and Maior-Swenson equations.

• Sijohaknonchong
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• v.42
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• pp.93-115
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• 2015

Dynamics of Sijo was regarded as a genre of 'closed nature' once. But ironically thanks to the 'closed nature', today dynamics of Sijo is refocused in diverse fields. Sijo is quoted not only in its original field of literature, but also in writing study. Quite remarkably, it is often referred to in the field of literary therapy, further in emotional healing. This article discussed the dynamics of Sijo as a manifestation of emotion especially called Gamsung in the process of the refocus. It is to show effectively that as a literary genre, Sijo can interact and share what is reasonal as well as what is emotional and sentimental in a poem as an emotional container beyond the lyricism Sijo has. Of course, it is also clear that the concept of lyricism may limit the dynamics of Sijo itself. Thus, the key word 'Gamsung' mainly referred to in this article was used to show the dynamics which Sijo has as much as possible, overcoming the limitation. That is, the purpose of the study is to prove that Sijo is the genre to represent human emotion most dynamically by reviewing the reasonal aspect of Sijo in addition to its emotional disposition which has been estimated to focus on sentiment or emotion. In the process of reinterpreting the structure of Sijo, the specific analysis on such emotional disposition and reasonal aspect was conducted by structurizing that as '(1) Facing, (2) Feeling dynamical, (3) Interpellating by feeling, and (4) feeling by sensation'.

• Journal of Korean Home Economics Education Association
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• v.20 no.1
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• pp.1-19
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• 2008

The purpose of this study was to find out the stress level, dietary behavior score, and relationship between stress level and dietary behavior score of middle school male students in Daejeon. Eight items of stress such as family, study, amusement, health, friend, girl friend, teacher, and daily life, and 3 items of eating behavior such as diet regularity, dietary balance and healthy diet were analyzed. The data were gathered by questionnaires from 140 students in Joong gu, Daejeon city during July 10 to 14, 2006 and 128 questionnaires(91.4%) were analyzed. The conclusion of this study were summarized as follows: 1st, the total stress level was 2.36 out of 5 full scales. The study related stress was the highest 2.93, and the stress related to girl friend was the lowest, 1.96, though there were no significant differences among the 8 kinds of stress items. 2nd, the total score of dietary behavior was 3.02 out of 5 full scales. 3rd, when the students were divided into 3 groups(low, meddle, and high group) according to the stress level, the middle group showed the highest score of dietary behavior, while the high group showed the lowest score, but non-significant. 4th, according to the relationships between stress levels and dietary behavior scores, significant relationships were found between the total stress score and dietary balance. And diet regularity score were influenced by stress items such as family related, study related, and health related.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.78-84
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• 2019

Recently, bio-butanol is being promoted as environmentally friendly sustainable energy. However, some problems are still obstacle for commercialization of bio-butanol: the development of cheap biomass and enhancement of fermentation ratio and preparation of economical separation process for fermented products. In the conventional ABE biobutanol fermentation process, organic acids with acetone, butanol, and ethanol are produced. Therefore, it is necessary to study phase equilibrium data and mixture properties for the design and operation of separation process. However, there is lack of design data for organic acids except acetic acid contained system. In this study, therefore, binary solid-liquid equilibria (SLE) and mixture properties: the excess molar volumes ($V^E$), molar refraction deviation (${\Delta}R$) and deviation of viscosity (${\Delta}v$) at 298.15 for $C_3-C_6$ organic acid were reported. The experimental SLE data were correlated with the NRTL and UNIQUAC activity coefficient model with less than 0.5 K of root mean square deviation (RMSD). In addition, $V^E$, ${\Delta}R$ and ${\Delta}v$ for the same binary systems were satisfactorily fitted using the Redlich-Kister polynomial with less than ca. 0.004 standard deviation.

• Korean Journal of Culture and Social Issue
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• v.26 no.4
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• pp.351-378
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• 2020

The purpose of the study was to identify the latent classes of meta-awareness of gender discrimination among Korean young adults using Latent Profile Analysis based on 'perceived ambivalence toward men among women', 'perceived ambivalent sexism among men', 'perceived gender(reverse-) discrimination in Korea'. After identifying the latent classes, the difference between gender role conflict, sense of distance from the opposite sex, and support for gender discrimination issues were explored among the classified groups. As a result, 3 latent classes among women and 2 latent classes among men were identified. Latent classes among women were named 'women with low sensitivity of sexism', 'women with high sensitivity of sexism' and 'women against sexism' and latent classes among men were named 'men with perception of gender equality', 'men with perception of reverse discrimination'. Types with higher levels of meta-awareness of gender discrimination were related with higher gender role conflict and higher sense of distance from the opposite sex. Among women, types with higher levels of meta-awareness of gender discrimination perceived higher levels of gender discrimination and showed more support for gender discrimination issues while among men, types with higher levels of meta-perception of gender discrimination only perceived higher levels of reverse discrimination. Based on the present findings, implications about the severe gender conflict among Korean young adults are further discussed in the article.

• Journal of the Korea Society of Computer and Information
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• v.11 no.6 s.44
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• pp.87-97
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• 2006

This study aims to identify the effect that the perceived usefulness and perceived ease of use have on learner flow in e-learning community. Based on literature review and Technology Acceptance Model(TAM), a potential model and five hypotheses were suggested. Questionnaire was carried out among 62 members of one e-learning community for preparatory teacher Cronbach alpha of the questionnaire was.88. The collected data were analyzed through correlation analysis and path analysis. The results of this research are as follows. Three hypotheses were adopted: Perceived usefulness will affect on attitudinal flow, Perceived ease of use will affect on attitudinal flow. and Attitudinal flow will affect on behavioral flow. Two hypotheses were rejected;. Perceived usefulness will affect on perceived ease of use and Perceived ease of use will affect on behavioral flow. The model revised through the results of path analysis had good-fitness. That is. overall fit measures (RMSEA, CFI. NNFI). indexes that show the suitability of the model were quite good. Findings of this study suggested the important strategies for designing e-learning community in order to promote learner flow.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.893-900
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• 1997

In this study, vapor-liquid equilibria of a binary system, which consists of glycerol and water, are measured using a vaporrecirculating modified Othmer still at various subatmospheric pressures. The constituent components of the binary system considered in this study exhibit a large difference in the boiling temperatures. Since it is generally observed that the properties of a mixture greatly differ from those of the pure components, the phase equilibrium characteristics of a mixture can not be predicted from the properties of the pure components. Furthermore, an abrupt increase in the boiling temperature occurs as the concentration of the higher boiling component exceeds a certain value. Therefore, it is essential to acquire realistic phase equilibrium data of the mixture for industrial applications. Using the UNIQUAC model, the experimental vapor-liquid equilibrium data are correlated with good accuracy. The thermodynamic consistency test is also performed to ensure soundness of the data.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.301-301
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• 2019

수위 관측 지점의 선정은 관측 기록의 목적, 지점의 접근성 등에 의해 결정되며, 수위는 유량을 계산하기 위한 필수 자료이므로 수위 관측 지점의 위치를 선정하는데 있어 수리조건은 매우 중요한 요소이다. 이에 수위관측소(WLS, Water Level Station)는 홍수예경보, 수해방지 등의 치수계획과 하천운영, 용수공급 등의 이수계획 및 생태계 보전을 위한 수질관리계획 등의 목적을 달성할 수 있는 지점에 WMO에서 제시한 수위관측소의 최소 밀도를 고려하여 설치된다. 한국의 경우 치수측면에서 홍수예경보시스템의 홍수예보 대상지점과 홍수유출 계산지점을 가장 중요한 요소로 판단한다. 이에 홍수통제소에서 운영하는 홍수예보 프로그램에 적절한 수위관측망을 고려하기 위하여 프로그램에서 사용되고 있는 소유역 출구점 또는 합류점을 모두 수위관측소 위치로 포함시키고 있다. 인도네시아 Citarum강 홍수예경보 모형의 실행 및 검정을 위해서는 주요 지류의 출구마다 수위관측소를 설치하는 것이 바람직하나, 수위관측소의 설치 및 운영에는 많은 비용이 소요되기 때문에 주어진 예산을 고려해야 하며, 홍수예보를 실시하는 이유는 홍수로 인한 피해를 경감시키기 위한 것이기 때문에 인구와 홍수피해 잠재성이 높은 지점을 위주로 설치를 계획하여야 한다. 사업 대상지역인 Citarum강에서 BBWSC가 운영 관리하는 WLS는 29개소이며, 이 중 대상지역인 Upper Citarum Basin(UCRB)에는 20개소의 WLS가 운영되고 있다. 본 설계에서는 $300km^2$당 1개소의 수위관측소를 설치하는 것을 기준으로 설정하여 홍수예경보가 필요한 WLS 8개소를 도출하였으며, 소유역의 출구점 또는 합류점 등을 고려하여 수위관측소 위치를 결정하였다. 또한 UCRB의 과거 홍수피해상황, 과거 홍수범람실적, 홍수범람도 등을 조사하였으며, 실시간 자료 전송을 위한 통신 환경, 차량의 접근 용이성 및 하천구역 대표성 등을 고려하여 홍수예경보 구축을 위한 최적의 수위관측망을 설계하였다.