• Journal of Biosystems Engineering
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• v.27 no.1
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• pp.33-38
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• 2002

The indicated power of Stirling engine was affected by the heat exchange effectiveness of the regenerator. The temperature difference of working fluid between the expansion and the compression space of Stilting engine depends on the heat exchange effectiveness of the regenerator. The influence of the temperature ratio of expansion space to compression space of Stirling engine on the indicated power was analyzed by using Schmidt analysis in this study. In the Stirring engine, as the temperature ratio increased, the indicated power generally decreased. Therefor, it is necessary to develope the regenerator of high effectiveness. The actual indicated power was shown 64.9 percent of the predicted indicated power in maximum and 47.2 percent of that in minimum due to increased dead volume of engine, the loss of flow friction and heat transfer in the regenerator.

• Fashion & Textile Research Journal
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• v.13 no.2
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• pp.215-225
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• 2011

The purpose of this study is to identify the differences in persuasive effectiveness of visual merchandising according to merchandise class. For the experiment, 8 stimuli brands were selected. A total of 360 questionnaires were obtained from college students. The results were as follows. First, VM cognition were divided into 3 factors by confirmatory factor analysis: coordination, attractiveness, and function. Second, coordination and function had a positive effect on brand attitude. Third, brand attitude had a positive impact on brand loyalty. Fourth, it was revealed that merchandise class had a moderating role in the influence of VM cognition on brand attitude. This study has a meaning in that the theoretical extension of previous studies on VM was executed and demonstrated the moderating role of merchandise class when brand attitude was formed by VM cognition.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.2
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• pp.1-7
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• 2001

Use of high yield pulp and recycled fiber as raw materials and water system closure result in higher fines content and buildup of organic and inorganic contaminants in white water. These are detrimental for the effectiveness of chemical additives including retention aids. Thus it is imperative to employ a retention systems that maintains its efficiency in closed papermaking system for reducing fresh water consumption. The performance of four different microparticle retention systems including cationic polyacrylamide (C-PAM)/bentonite, highly charged cationic starch (HCS)/silica, C-PAM/micropolymer, cationic guar gum (CGG)/silica was evaluated and compared at three different levels of papermaking system closure. Buildup of detrimental substances in a closed white water system increased cationic demand and finally reduced the performance of retention systems. Cationic starch and guar gums maintained their effectiveness in retention in closed white water systems contaminated with anionic trashes because of their structural rigidity and hydrogen bonding ability. Particularly, cationic guar gums, due its stiffness of molecular structure, appeared perform better than catinonic starch.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.5
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• pp.1-9
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• 2003

Effectiveness of the microparticle retention systems in improving drainage, retention, formation has been recognized for many years. In this study the effectiveness of crosslinked cationic corn starches and silica-based microgels as components of Compozil system has been evaluated. It was shown that improvements in retention and strength could be achieved by employing crosslinked cationic corn starches especially at high conductivity. Silica-based microgels with better performance in retention and drainage than a commercial colloidal silica sol have been made through a reaction of sulfuric acid and sodium silicate solutions.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.43-49
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• 1999

Effectiveness of the microparticle retention systems in improving dramage, retention, formation has been recognized for many years (1, 2, 3, 4, 5). In this study the effectiveness of crosslinked cationic corn starches and silica-based microgels as components of Compozil system has been evaluated. It was shown that improvements in retention and strength could be achieved by employing crosslinked cationic corn starches especially at high conductivity. Silica-based microgels with better performance in retention and dramage than a commercial colloidal silica sol have been made through a reaction of sulfuric acid and sodium silicate solutions.

• ETRI Journal
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• v.37 no.2
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• pp.428-437
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• 2015

This study was conducted to analyze the effect of information security activities on organizational performance. With this in mind and with the aim of resolving transaction stability in the securities industry, using an organization's security activities as a tool for carrying out information security activities, the effect of security activities on organizational performance was analyzed. Under the assumption that the effectiveness of information security activities can be bolstered to enhance organizational performance, such effects were analyzed based on Herzberg's motivation theory, which is one of the motivation theories that may influence information protection activities. To measure the actual attributes of the theoretical model, an empirical survey of the securities industry was conducted. In this explorative study, the proposed model was verified using partial least squares as a structural equation model consisting of IT service, information security, information sharing, transaction stability, and organizational performance.

• Korean Journal of Construction Engineering and Management
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• v.19 no.1
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• pp.65-73
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• 2018

Since unfair trading practices between participants in construction project are common, the government has enforced several policies and systems to prevent or minimize the unfair trading practices in construction industry. However, not much attention has been paid to figure out which policies or acts are working or not. This paper analyzed the effectiveness of the policies and acts which are being implemented to prevent unfair trading practices and provided several suggestions to improve the performance of those acts. Survey was conducted to industry experts to collect data regarding their perceptions on those policies and acts. Then the effectiveness of the policies and acts were analyzed in terms of their importance and performance through IPA (Importance-Performance Analysis) based on the survey result. It was found through IPA that execution related acts such as investigation, exposure, and punishment for unfair trading practice have shown low effectiveness in entire construction process and dispute arbitration and mediation related center operated by authority showed low performance too. To improve the effectiveness of those acts, dispute arbitration system improvement, investigation & reporting system consolidation and enhancement practical binding force of punishment and penalty were suggested. Most of all, rules and culture for fair trading should become more established in construction industry by preventing conflict among participants through active communication.

• Journal of Korea Society of Digital Industry and Information Management
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• v.18 no.4
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• pp.55-65
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• 2022

The purpose of this study is to develop online educational contents and verify its effectiveness in order to strengthen the learning capabilities of college students. The theme of mind map online education contents is a mind map series for effective learning arrangement, and has been developed into a total of six contents. Each contents consisted of 20-30 minutes, and the details consisted of the concept, principle, learning case, how to write a mind map, and how to use a digital mind map. The results of the study are as follows. First, it was confirmed that the higher thinking ability of college students who took the mind map online education contents was improved. Second, it was confirmed that the self-directed learning attitude of college students improved after taking the mind map online education contents. Third, the reason why students' higher thinking ability and self-directed learning attitudes improved in this study is that they were developed in consideration of the composition of contents and appropriate video time. Therefore, in order to increase the effectiveness of online educational contents, it is necessary to examine specific cases using concepts from conceptual approaches to specific topics, and to faithfully reflect the procedure in which each learner can actually use the concept.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.3
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• pp.869-885
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• 2012

The purpose of this study is to present innovative approaches for u-Learning environment in public education with Digital Textbook. The Korean Government has been making efforts to introduce the u-Learning environment to maximize the learning effect in public education with Digital Textbook. However, there are only a few studies that analyze the effectiveness of u-Learning environment and Digital Textbook. This paper reviews the current status of u-Learning environment in Korea and analyzes the satisfaction level with Digital Textbooks. The first survey regarding technological factors was collected from 197 students. The results of the survey revealed that the level of satisfaction has declined over a year. The weakness of the study is that the sample frame is insufficient and survey questions did not reflect diverse factors of learning effectiveness. To supplement these shortcomings, 2,226 students were asked about learning performance. The results of the survey showed that the satisfaction with Digital Textbooks is much higher than that of paper textbooks. However, this paper is limited to u-Learning environments in public education. Therefore, research needs to be improved by reflecting both public and private sectors of education in following studies. This paper suggests useful guidelines to educators in improving their u-Learning environment.

• Journal of Korea Society of Digital Industry and Information Management
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• v.20 no.2
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• pp.49-61
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• 2024

This study developed an online learning support program to provide academic support for students on academic probation by considering the positive perception and advantages of online education and at the same time reflecting the difficulty in contacting students who have been placed on academic probation. The program consisted of topics and contents that could increase academic self-management and academic resilience of college students on academic probation, and the purpose was to verify the effectiveness of the online learning support program after operation. The research results are as follows. There was a significant difference in academic self-management, learning regulation, and positive attitude of college students on academic probation. This can be seen as the fact that college students on academic probation acquired the knowledge, skills, and attitudes necessary for studying, and their determination to study had a positive effect on their academic resilience. The significance of this study is that it developed a program that can help improve the academic resilience of college students on academic probation and analyzed its effectiveness.