• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.747-752
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• 2009

This research was performed by means of several different virgin granular activated carbons (GAC) made of each coal, coconut and wood, and the GACs were investigated for an adsorption performance of bromate in a continuous adsorption column. Breakthrough behavior was investigated that the breakthrough points of the virgin two coals-, coconut- and wood-based GACs were observed as 9252 bed volume (BV), 6821 BV, 5291 BV and 2431 BV, respectively. The experimental results of adsorption capacity (X/M) for bromate showed that two coal- based GACs were highest (1334.5 and 798.2 ${\mu}g$/g), the coconut-based GAC was intermediate (668.6 ${\mu}g$/g) and the wood-based GAC was lowest (156.8 ${\mu}g$/g). The X/M of the coal-based GACs was 2~8.5 times higher than the X/M of the coconut-based and wood-based GACs. The results of carbon usage rates (CURs) for the virgin two coal-, coconut- and wood-based GACs were shown as 0.19, 0.25, 0.33 and 0.71 g/day respectively. The adsorption capacity, k values, were also investigated by means of the GACs for bromate. The k values of two coal-, coconut- and wood- based GACs for bromate were found to be 121.3, 76.7, 43.3 and 14.6 respectively. This results suggested that using the virgin GAC made of coal was the best selection for removal of bromate in the water treatment for an advanced treatment.

• Journal of Global Scholars of Marketing Science
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• v.10
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• pp.1-26
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• 2002

The present study examines the role of subjectively perceived factors of the attitude toward web shopping in forming an intention to use a web shopping intention. An integrative research model is presented and tested empirically. It includes the following three aspects of belief in Davis' TAM: perceived usefulness, perceived ease of use, perceived enjoyment. Specially, internet self-efficacy, or the belief in one's capabilities to organize and execute courses of Internet actions required to produce given attainments, is a potentially important factor in efforts to gain more favorable attitude toward web shopping close the digital divide that separates experienced Internet users from novices. Prior research on Internet self-efficacy has been limited to examining specific task performance and narrow behavioral domains rather than overall attainments in relation to general Internet use, and has not yielded evidence of reliability and construct validity. Survey data were collected to develop a reliable operational measure of Internet self-efficacy and to examine its construct validity. Also, much previous research has established that perceived ease of use is an important factor influencing user acceptance and usage behavior of information technologies. However, very little research has been conducted to understand how that perception forms and changes over time. The present study examines that higher internet self-efficacy is more getting favorable web shopping attitude, and web shopping intention as more as usefulness, enjoyment through the internet.

• Journal of the Korea Concrete Institute
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• v.23 no.5
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• pp.581-590
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• 2011

Since ultra-high performance cementitious composites (UHPCC) not only represents high early age shrinkage strain due to its low water-to-binder ratio (W/B) and high fineness admixture usage but also reduces the cross section of structure from the higher mechanical properties, it generally has more shrinkage cracks from the restraints of formwork and reinforcing bars. In this study, free and restrained shrinkage experiments were conducted to evaluate the suitability of incorporating both expansive admixture (EA) and shrinkage reducing agent (SRA). The test results indi-cated that approximately 40~44% of free shrinkage strain was decreased. Also, the results showed that 35% and 47% of residual tensile stresses were relieved by synergetic effect of SRA and EA, respectively. Residual tensile stresses from ringtest were relaxed by approximately 61% and 64% of elastic shrinkage stresses due to SRA and EA, respectively, because of the tensile creep effect. Therefore, the creep effect should be considered to precisely estimate the restrained shrinkage behavior of concrete structures. The degree of restraint of UHPCC was approximately in the range of 0.78~0.85. The addition of combined EA and SRA showed minute influence on the degree of restraint. However, the effect decreased when thicker concrete ring was used. Tensile creep strains were measured and compared to the predicted values from 4-parametric prediction model considering time dependent restrained forces.

• Journal of Korea Society of Industrial Information Systems
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• v.20 no.1
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• pp.79-90
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• 2015

This study investigated the effects of 'K-POP' preference on purchase intention of Korean products. Especially, it revealed the mediating role between the participation intention of Korean culture event and the purchase intention of Korean products. Further, we examined the difference in the path relation according to the use-behavior of Korean wave contents. In this proposed model, we can see 'K-POP' preference had a positive effect on participation intention of Korean culture event, but it was not significant for purchase intention of common products. The participation in Korean culture event had significant effects on the purchase intention of Korean culture products and the purchase intention of common products. However, the purchase intention of Korean culture products had no significant effects on the purchase intention of common products. Thus, our finding showed that higher preference of 'K-POP' did not make cause purchase intention of common products. Further, the higher the preference of 'K-POP' was, the higher the participation intension of Korean culture event was and, as a result, the purchase intention of common products got higher. In addition, path analysis results according to the media usage behaviors show that Chinese consumer who uses the internet and has a higher preference of 'K-POP' had a positive effect on the purchase intention of common products. Furthermore, it has a positive effect on both purchase intension of Korean culture products and purchase intension of common products. In case of Chinese consumer who use the television, radio and newspapers, K-POP preference had no significant effect on the purchase intension of common products.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.777-787
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• 2020

With the development of the Internet and the spread of mobile devices, the online market is growing rapidly. As the number of customers using online shopping malls explodes, research is being conducted on the analysis of usage behavior from customer data, personalized product recommendations, and service development. Thus, this paper seeks to analyze the overall process of online shopping malls through process mining, and to identify the factors that influence users' purchases. The data used are from a large online shopping mall, and R was the analysis tool. The results show that customer activity was most prominent in categories with event elements, such as unconventional discounts and monthly giveaway events. On the other hand, searches, logins, and campaign activity were found to be less relevant than their importance. Those are very important, because they can provide clues to a customer's information and needs. Therefore, it is necessary to refine the recommendations from related search words, and to manage activity, such as coupons provided when customers log in. In addition to the previous discussion, this paper proposes various business strategies to enhance the competitiveness of online shopping malls and to increase profits.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.232-241
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• 2016

Among city parks, children's parks are more accessible than other parks in the city, and there are many users. They are used not only for children's playgrounds, but also for relaxation and leisure spaces for local residents. On the other hand, as a result of focusing on the quantitative increase by the engineering division by the Urban park Act, the consideration of the users of various classes is insufficient. The purpose of this study was to analyze the actual use of children parks in single - family housing and communal housing areas, and to identify the problems and future directions of the use of children parks. For this purpose, a case study and a document survey were conducted. First, through scholarship research, the theoretical review and the present situation were summarized based on the data, such as the papers and research reports related to the existing children's park. The status of the location, facilities and management were then identified through interviews and site visits with the children's park management staff. As a result, the children's park was utilized as a leisure space with high accessibility in the living area. As a result, the residence time of most users was within 1 hour to 2 hours. In particular, use by elderly people was higher than the use by children. Therefore, it would be desirable to design the future planning of the children's parks and to plan the arrangement in accordance with the future - oriented multi - purpose neighborhood type children's park.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.3
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• pp.189-199
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• 2009

The amount of information on the Web is explosively growing as the Internet gains in popularity. However, only a small portion of the information on the Web is truly relevant or useful to the user. Thus, offering suitable information according to user demand is an important subject in information retrieval. In e-commerce, the recommender system is essential to revitalize commercial transactions, raise user satisfaction and loyalty towards the information provider. The existing recommender systems are mostly based on user data collected at servers, so user data are dispersed over several servers. Therefore, web servers that lack sufficient user behavior data cannot easily infer user preferences. Also, if the user visits the server infrequently, it may be hard to reflect the dynamically changing user's interest. This paper proposes a novel personalization system analyzing the user preference based on web documents that are accessed by the user on a user device. The system also identifies non-content blocks appearing repeatedly in the dynamically generated web documents, and adds weight to the keywords extracted from the hyperlink sentence selected by the user. Therefore, the system establishes at an early stage recommendation strategies for the web server that has little user data. Also, user profiles are generated rapidly and more accurately by identifying the information blocks. In order to evaluate the proposed system, this study collected web data and purchase history from users who have current purchase activity. Then, we computed the similarity between purchase data and the user profile. We confirm the accuracy of the generated user profile since the web page containing the purchased item has higher correlation than other item pages.

• International Journal of Highway Engineering
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• v.13 no.4
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• pp.117-122
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• 2011

Asphalt concrete pavement can be widely seen on urban streets, highways, parking lots, and bike trails. Asphalt concrete pavement is relatively temperature sensitive materials due to the viscoelastic behavior, which can be defined as flexible performance in summer and rigid performance in winter. In terms of maintenance, it can be fixed quite easily if damaged. In addition, asphalt concrete pavement is generally found to be black and grey in color. However, several colors can be adopted to change the appearance of plain old boring, black and grey. Generally, there are two types of color systems in hot mix asphalt concrete materials. One system uses colored cementitious material that is applied to pavement surface through coating the surface of the asphalt pavement. The major disadvantage to this system requires a careful skill set to be used on the construction site in order to prevent taking off the cementitious material. The other coloring system colors the asphalt hot mixtures through using color additives. The main advantage to this system is that the asphalt pavement layer is colored using the same techniques that are already used in paving. The disadvantage is that the colors are limited to mainly reds and browns. In this study, a suggested color additive was evaluated, based on rutting, moisture sensitivity, and fatigue cracking performance.

• Korea journal of population studies
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• v.35 no.1
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• pp.181-209
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• 2012

Employment form and gender as stratification factors may generate health disparities in Korea. Previous studies have examined the existence of health disparities by employment form and gender. However, few studies examined how the health disparities can be reduced effectively. This study intends to confirm the existence of health disparities between employment-gender groups and explore the effective health resources which can reduce the possible disparities. Using a national probability sample of Korean adults collected in 2011, we attempts to test the interaction effects between employment-gender groups and health resources on self-rated health. For health resources, 24 variables of five dimensions(social relationship, psychological resource, activity factor, health behavior, and usage of medical service) are taken into account. In results, first, the health levels of the other three employment-gender groups are worse than that of male-regular workers. Second, the effective health resources which can reduce the health disparities are different across the employment-gender groups. An effective health resource for female-nonregular workers is a peaceful relationship with her children. Effective health resources for male-nonregular workers are peaceful relationships with his parents and siblings, low stress, religious activity, and exercise. An effective health resource for female-regular workers is interpersonal trust. These results imply that personal or social interventions for health of specific disadvantaged groups need to focus on specific resources which are more effective for the groups.

• Journal of Global Scholars of Marketing Science
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• v.13
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• pp.113-133
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• 2004

The present study examines the the role of subjectively perceived factors of the attitude toward job-seeking activities in forming an intention to use a web. An integrative research model is presented and tested empirically. It includes the following two aspects of belief in Davis' TAM: perceived usefulness, perceived ease of use. Specially, internet job-seeking efficacy, or the belief in one's capabilities to organize and execute courses of Internet actions required to achieve given goals, is a potentially important factor in efforts to gain more favorable attitude toward Internet uses. Survey data were collected to develop a reliable operational measure of Internet job-seeking efficacy and to examine its construct validity. An four-item Internet job-seeking efficacy scale developed for the present study was found to be reliable and internally consistent. Also, many previous studies have established that perceived usefulness is an important factor influencing user acceptance and usage behavior of information technologies. However, very little research has been conducted to understand how that perception forms and changes over time. The current work presents and tests the determinants of perceived usefulness. The present study found that higher internet job-seeking efficacy is an important concept which is significantly related to job-seeking activities by positively influencing intention and performance as well as usefulness on the Internet.