• Composites Research
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• v.37 no.2
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• pp.68-75
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• 2024

Polypropylene (PP), a thermoplastic resin with excellent mechanical, thermal, chemical, and water resistance properties, has been attracting attention due to its economic efficiency and recyclability. However, repeated processing of thermoplastic resins can lead to property degradation, and the point at which quality degradation occurs varies depending on the processing conditions. In this study, we evaluated the performance changes of composite materials with repeated processing by blending PP resin with various additives and conducting extrusion and injection processes repeatedly. In addition, we evaluated the mechanical properties of composite materials to evaluate the effect of MFI value change during repeated processing on fiber impregnation in composite material processing.

• Korean Journal of Materials Research
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• v.34 no.7
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• pp.330-340
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• 2024

Al-Mg-Si alloys are light weight and have excellent corrosion resistance, and are attracting attention as a liner material for high-pressure hydrogen containers in hydrogen fuel cell vehicles. Because it has excellent plastic hardening properties, it is also applied to car body panel materials, but it is moderate in strength, so research to improve the strength by adding Si-rich or Cu is in progress. So far, the authors have conducted research on the intergranular fracture of alloys with excessive Si addition from the macroscopic mechanical point of view, such as specimen shape. To evaluate their impact tensile properties, the split-Hopkinson bar impact test was performed using thin plate specimens of coarse and fine grain alloys of Al-Mg-X (X = Cr,Si) alloy. The effect of the shape of the specimen on the characteristics was studied through finite element method (FEM) analysis. As a result, it was found that the intergranular fracture of the alloy with excessive Si depended on the specimen width (W)/grain size (d), which can be expressed by the specimen size and grain size. As W/d decreases, the intergranular fracture transforms into a transgranular fracture. As the strain rate increases, the fracture elongation decreases, and the fracture surface of the intergranular fracture becomes more brittle. It was confirmed that intergranular fracture occurred in the high strain rate region even in materials with small grain sizes.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.759-772
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• 2017

This experiment was conducted to develop control method for Bemisia tabaci (Gennadius) on eggplant using sticky trap method. According to the color of the sticky traps, the attractiveness of the B. tabaci was the highest in the yellow trap, followed by the green and orange. However, white, blue, red, black and green sticky traps have reduced attractiveness of B. tabaci. In order to improve the efficiency and attractiveness of sticky trap to the B. tabaci, the different kinds of sugars such as glucose, fructose, oligosaccharide, starch syrup and pure sugar were added to sticky traps respectively. However, the effect of B. tabaci attractiveness was low in starch syrup, pure sugar, and non-treated sticky traps. The attracting effect of B. tabaci was depending on the location of sticky trap. The highest value was obtained where sticky traps were located in the top of the eggplant, followed by 30 cm above from the top level. In addition, we were installed up to 40 sticky traps to determine the optimal amount of sticky traps to control B. tabaci in eggplant. When increasing the sticky traps, the number of adult and nymphs of B. tabaci were tended to be decreased significantly. This tendency was more effective in the latter stages than in the early stages. As the number of sticky traps increased, not only the growth rate of eggplant, leaf length, and stem diameter were to be better. But also number of fruits and product marketable value were increased at the early stage of growing as well. The study had proven that the sticky traps had an effect on increasing the yield at the early stage of growth, but the efficiency of controlling decreased due to the high density of B. tabaci of the next generation.

• Journal of Distribution Science
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• v.15 no.11
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• pp.83-93
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• 2017

Purpose - The study aims to analyze the VMD(Visual Merchandising) perception factors in recent sporting goods store and clarify the effect of each VMD perception factors on brand image, satisfaction, and customer revisit intention. The VMD perception factors play an important role in attracting and actually inducing sales to the visiting customers. It has investigated the effect of VMD perception on customer satisfaction and revisit intention. It is expected that the company's marketing strategy with VMD will be differentiated and competitive in sports item stores, brand image enhancement, customer retention, and acquisition. Research design, data, and methodology - In order to verify the hypotheses of this study, a total of 380 questionnaires had been distributed. 360 respondents were used in the final analysis excluding 20 respondents' incomplete answers. The SPSS 18.0 program was used and the data analysis was conducted for the demographic characteristics and distribution behavior. Principal Components Analysis was used for the common factor extraction for validity analysis, and factor analysis was conducted to verify such as validity in brand image or brand attitude. As for Multiple regression analysis, was performed to verify and in the research model, and in and , the mediation was defined through the Sobel Test in order to verify the brand image mediating effects on VMD, store satisfaction, and revisit inquiry of sports store. Results - Qualitative research shows that VMD sub-variables such as aesthetic, fitness, and functional convenience influence store satisfaction and revisit intention. As a result of analyzing the mediating effect of the brand image, the more VMD is strengthened, the more brand image is improved and store satisfaction is also increased. Conclusions - VMD enhancement requires a VMD strategy aligned with the company's management policies and objectives, a visual directing and consistent concept that delivers a strong message to customers. The customer actual purchasing behavior is a combination of various factors such as sports item stores' interior design, display, advertisement promotion like POP(Point of Purchase), salespersons and their service quality, so that the VMD image and the brand image must be consistent and a unique strategic plan is required.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.1
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• pp.57-67
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• 2020

Recently, smart cities are attracting attention as a solution for a plethora of urban problems, including transportation, environment, safety, and energy. However, despite a substantial body of research dealt with the concept, trends, policy, and legal institutions of smart cities, few researchers have examined how the smart city services influence the cities from the dynamic perspective that considers the entire cycle of a city, including its growth, stagnation, and decline. Thus, it is vital to understand how the city changes with time from the view that a city is a system of sub-elements-population, industry, transportation, environment, housing, and land-closely interacting together. Within this context, this study explores how the urban dynamics of Anyang-city develop for the long term using the System Dynamics method and analyzes the effect of smart city project investment on the dynamics of Anyang-city. According to the result, Anyang-city is a "mature and stable" type, and its population is expected to decrease slowly by 2040. Specifically, the Anyang-city population will be reduced to 553,000 by 2030. It was analyzed that the number will decrease to 543,000 by 2040. It was also found that the investment in smart city projects in Anyang, based on the Plan for Anyang Smart City, would have the following effects: easing population decline, increasing number of businesses, improving urban safety index, and increasing average driving speed. The population will grow by 4,000 and the number of businesses will increase by 761 than before budget investment. The result of this paper is expected to contribute to identifying and predicting the effect of smart city policies from a long-term perspective.

• Journal of the Korean association of regional geographers
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• v.10 no.3
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• pp.624-641
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• 2004

Since 1995, when local autonomy policies were enacted in Korea, many local governments have adopted festival-centered place-marketing strategies, in order to develop their regional economies by attracting tourists, as well to provide the general public with information about local comparative advantages. This study assesses the spread effect of the Cheongdo Bull-Fighting Festival upon the regional tourism industry, by analysing questionnaire data obtained from festival visitors and merchants at other major tourist attractions in the area. It is concluded that the Cheongdo Bull-Fighting Festival has been insufficient in attaining the objective of developing the regional economy and the tourism industry, because at present, most of the festival spectators are not tourists as such, but rather residents of the Cheongdo daily community (Daegu metropolitan area), and they do not visit other major tourist attractions in conjunction with attending the festival. It is recommended that planning authorities adopt a strategy explicitly designed to increase the "tourists to local residents" ratio, and to improve tourism services to facilitate intra-regional movement of tourists and visitors alike.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.434-442
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• 2019

Low Impact Development(LID) techniques has been attracting attention as a countermeasure to solve frequent flood damage in urban areas. LID is a techniques for returning to the natural hydrological cycle system by infiltrating the runoff from the impervious surface into the soil. The Bio-retention, one of the LID element technology has outflow reduction effect by reserving and infiltrating storm water runoff from watersheds. Recently, a number of studies have been carried out as interest in the reduction of storm water runoff and non-point pollutants in Bio-retention has increased. However, quantitative analysis on the outflow reduction of Bio-retention applied to small watershed is insufficient. In this study, Bio-retention model was constructed in a small watershed using K-LIDM which is capable of hydrologic analysis. When the storage capacity was increased or dividing the Bio-retention and watershed, the outflow reduction effect was 20% according to the storage capacity increase and 5~15% in the distributed Bio-retention system. The results of this analysis will be used as the basic data of future Bio-retention research related to watershed characteristics, vegetation type and soil condition.

• The Journal of the Korea Contents Association
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• v.19 no.1
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• pp.682-695
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• 2019

In recent years, using a connected platform, companies have built and implemented a mobile viral marketing strategy to attract new customers and to have long-term relationships with existing customers. The emergence of interactive Web 2.0 has led to an explosive increase in customer engagement, and practitioners have become interested in connected platform to build close relationships with their customers. However, the study on the effectiveness of various customer influx methods using the connected platform that companies utilize for an increase of customer participation is insufficient. Based on the theoretical study of Sashi (2012), this study analyzes the actual mobile viral promotion of company A's open market shopping mall for the purpose of bringing new customers and having a long-term relationship with the new customers[1]. By analyzing the customer engagement type, the implications for the effectiveness of mobile viral promotion are suggested. First, as a result of the immediate effect of online viral promotion, promotions are partially effective in attracting new customers. Second, as a result of examining the change of customer engagement type in order to find out the long - term effect of online viral promotion, it was found that in most cases, new customers were not become satisfied customers and, Laggard Effect, which takes time to become a satisfied customer, has been confirmed.

• Journal of Intelligence and Information Systems
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• v.29 no.2
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• pp.149-170
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• 2023

This study analyzed the factors influencing users' intention to use the Metaverse by applying the extended technology acceptance model. In other words, the factors affecting users' intention to use the Metaverse were defined as technical characteristics (telepresence, interoperability, seamlessness, concurrence, and economy flow) and personal characteristics (social influence and perceived enjoyment) from the perspective of the Extended Technology Acceptance Model. For this purpose, a survey was conducted among men and women of various ages ranging from teenagers to 60s, and the data collected from 327 participants were analyzed using SPSS 22.0 and Smart PLS 4.0. The results showed that perceived usefulness and perceived ease of use, which are antecedents of the Extended Technology Acceptance Model, influence the intention to use Metaverse, and perceived ease of use influences perceived usefulness. Telepresence, interoperability and economy flow were found to have a positive effect on perceived usefulness, and interoperability, seamlessness and concurrence were found to have a positive effect on perceived ease of use. In addition, social influence and perceived enjoyment had a positive effect on intention to use the Metaverse. This study is significant in that it empirically analyzed the factors of users' acceptance of the Metaverse, which is attracting attention as a new platform that will bring significant changes to our daily lives and platform consumption environments.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2583-2591
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• 2013

A number of cities have been constantly decreasing their residents by the low quality of life and environment. A creative industry is being noticed for not only securing the competitiveness of the city but also increasing the number of population. Thus, the urban structure for inducing creative industry population becomes to major issue to the most of local governments. This study aims to suggest the relationships between urban structure and creative industry population based on different urban sizes. To measure the population of creative industry, this study used the 'National Business Survey' by the National Statistical Office, which classified the statistical data of industrial places on a basis of city, district, and borough. Based on the results of expert questionnaire surveys, it conducted an analysis on the importance of urban structure and drew some critical factors that have an important effect on attracting the population of creative industry. The relationships between creative industry population and urban structure evaluated by multiple regression analysis. This study found out that the cultural factors like cultural space or culture events were drawn as very significant factors that have a positive effect on the population of creative industry population. It is judged that the creation of culture environment, which can enrich the creative industry, is needed to strengthen the competitiveness of the cities.