• Steel and Composite Structures
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• v.46 no.3
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• pp.385-401
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• 2023

Steel is becoming increasingly popular due to its high strength, excellent ductility, great assembly performance, and recyclability. In reality, steel structures serving for a long time in atmospheric, industrial, and marine environments inevitably suffer from corrosion, which significantly decreases the durability and the service life with the exposure time. For the mechanical properties of corroded steel, experimental studies are mainly conducted. The existing numerical analyses only evaluate the mechanical properties based on corroded morphology at the isolated time-in-point, ignoring that this morphology varies continuously with corrosion time. To solve this problem, the relationships between pit depth expectation, standard deviation, and corrosion time are initially constructed based on a large amount of wet-dry cyclic accelerated test data. Successively, based on that, an in-situ pitting evolution method for evaluating the residual tensile strength of corroded steel is proposed. To verify the method, 20 repeated simulations of mass loss rates and mechanical properties are adopted against the test results. Then, numerical analyses are conducted on 135 models of corrosion pits with different aspect ratios and uneven corrosion degree on two corroded surfaces. Results show that the power function with exponents of 1.483 and 1.091 can well describe the increase in pit depth expectation and standard deviation with corrosion time, respectively. The effect of the commonly used pit aspect ratios of 0.10-0.25 on yield strength and ultimate strength is negligible. Besides, pit number ratio α equating to 0.6 is the critical value for the strength degradation. When α is less than 0.6, the pit number increases with α, accelerating the degradation of strength. Otherwise, the strength degradation is weakened. In addition, a power function model is adopted to characterize the degradation of yield strength and ultimate strength with corrosion time, which is revised by initial steel plate thickness.

• Architectural research
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• v.16 no.4
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• pp.157-166
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• 2014

This research investigates the design process of free-form architecture to understand the design strategy and changing factors during the development phase and the cause for them. It is aimed to foresee the changing factors from the design process and to reduce design changes. It analyzes the design changes of free-form architecture based on projects with finalized documentation or under construction in South Korea. Many free-form shapes of the free-form architectures have to be adjusted to rigid-form in order to satisfy function and be economical to build. The research finds three patterns in design changes. First, from the factors for design changes: function, constructability, design, program add/subtract, efficiency, circulation; Function and Constructability are the higher factors compared with the rest. The two are the design changes suitable for actual usage and cost savings. Second, each project has different predominant factors for design changes as the degree of free-form is different. Contrary to initial expectation, the greater the degrees of free-form of the competition scheme, the higher the rate of Function among the factors for design changes. Constructability is higher when the degree of the free-form is less than others. It means that the lower the degree of the free-form, the more properly planned the space of the building is. Last, Constructability of free-form architecture is considered during the earlier design phase than definite-form, one by which the design changes by comparing 'Before fixed Space Program' (BSP) and 'After fixed Space Program' (ASP) design changes. The research would be helpful as a reference for setting up competition guidelines to reduce trial and error during the design process.

• Journal of the Korea Society of Computer and Information
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• v.16 no.1
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• pp.153-161
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• 2011

Focusing upon the post-adoption stage of IS, this study reasoned that IS users' personality is one of major influencing factors of continuous IS usage intention and empirically examined how the degree of continuous IS usage intention is variable according to the IS users' personality types classified based on MBTI(Myers Briggs Type Indicator). In order to validate the research model and hypotheses, this study made a field survey of 330 IS users and statistically analysed response data. The results of empirical analyses showed that the intent of continuous IS usage was affected by self-efficacy of IS; and self-efficacy by self-leadership of IS; and self-leadership by IS user' personality type and expectation confirmation. That is, it was found that IS users' personality type and three intervening variables(expectation confirmation, self-leadership and self-efficacy) were significant predictors of the intent of continuous IS usage. This study is thought to be contributive to providing the theoretical basis of finding IS success factors in the post-adoption stage and the practical guideline for effective personnel management relevant to IS implementation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.10
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• pp.2389-2395
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• 2015

An accurate feedback about customer satisfaction is a very important factor to efficiently manage achievements in the service industry. However, Korea is lack of quantitative and standardized system of customer satisfaction measurement. This paper suggests standardized survey system with more in-depth and various methods of questionnaire survey as well as analysis which is able to efficiently evaluate customer satisfaction. This system is that investigates customer satisfaction of process based services, which uses various methods including simply designed questionnaires, customer satisfaction survey via mobile, and an investigation on follow-up satisfaction rate. In addition, we adopted scoring system to digitize a degree of satisfaction rate, so the suggested system provides an opportunity to improve specific objects those need to be improved by clearly evaluating a degree of satisfaction rate and applying various analysis techniques, such as IPA (Importance Performance Analysis), process analysis, and expectation analysis etc. This study substantiates suggested system through applying it to travel agency which is a representative enterprise of tour service.

• Journal of the Korea Society of Computer and Information
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• v.17 no.8
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• pp.145-161
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• 2012

This study aims to explore how the degree of education related to information systems and the Internet literacy affect perceived security risk and how these three variables affect online transaction intention based on the Technology Acceptance Model (TAM). Since using smartphone to purchase necessary products is increasing, the study provided two different cases of using the existing Internet and smartphone to buy products. As a result of an empirical test, the degree of information system education, internet literacy, and perceived security risk had significant effects on online transaction intention mediating perceived usefulness and perceived ease of use. Unlike the expectation, the more people have education related to information systems, the more they have knowledge about hacking or cases of privacy infringement, leading to even more concerns about security, thereby believing the Internet transactions require much effort. The more the education about information system, the more we have concerns about security; therefore, perceived security risk have a positive(+) effect on perceived usefulness not a negative(-) effect. Lastly, while the degree of education related to information systems has relations with the recognition of the usefulness of the Internet transaction, the study showed that there are no relations of recognizing the usefulness and the ease of use of smartphone.

• Korean Journal of Organic Agriculture
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• v.11 no.3
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• pp.1-19
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• 2003

The operation of a five day workweek seems to be increased continuously, Many city-workers will make good use of their spare time and search after a lot of devices that can seek for the maximum value of leisure utility. The demand of potential customers that want to enjoy weekend in farming villages is coming out greatly. That is, the condition of users that will travel the farming villages is getting better. But the actual states of farming villages are not ready in many parts yet. Therefore we must activate the tourist attraction in farming villages that can be satisfied the city-workers' expectation. And after making the sightseeing environment infrastructure, we must develop the programs intimate with environment, improve the sightseeing agricultural management and consolidate various systems as soon as possible. So in this study, after investigating the demand preference degree of city-workers, I tried to grope an activation plan with the base which will reach. Being more urgent what more, not the simple sightseeing agriculture that the farming experience was the focus of, but it is very important to develop the program of environment sightseeing agriculture. It will lay the stress on playing and education culture which city-workers can enjoy and experience. And with constructing the base facility like a city form, we must develop cheap and various goods and the execution of modernized weekend farms. For this, first the consciousness conversion against the customer management of farmers must precede and the change of government policy and the support polity is important. I hope that this study with the five-day workweek has the chance to contribute in the economic growth of farming villages and efficient use and management of the natural environment resources through the activation of sightseeing agriculture.

• Journal of The Korean Association For Science Education
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• v.21 no.5
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• pp.893-905
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• 2001

Korean students ranked the 3rd out of 32 participating countries in the first cycle of PISA(Programme for International Student Assessment) science field, which assessed 15-years-old students' scientific literacy. PISA developed several variables such as parents' socio-economic status, parents' educational attainment, family wealth, and cultural possession, to investigate the effects of background variables on scientific literacy. On the other hand, motivation and engagement in science study were not given much attention, partly because science was the minor area in the first cycle of PISA. Therefore, PISA Korea developed a series of variables to collect data on students' learning motives and out-of-school activities in science as a national option. The results are as followings. First, Korea was found to be one of the PISA participating countries with the scientific literacy achievement least influenced by parents' socio-economic status, family wealth, and parents' cultural possession. Second, the degree of achievement in scientific literacy according to parents' educational attainment was in a positive correlation, similar to the overall tendency of PISA. Third, the most crucial learning motive for Korean students was their desire to develop scientific thinking abilities or obtain science knowledge. On the other hand, choosing jobs in the field of science or parental expectation was the least important learning motive. In particular, the motive for scientific learning was found to have a positive relationship with the degree of scientific literacy achievement. Therefore, the higher the students achievement, the stronger the motive for scientific learning in order to develop their ability to think scientifically or acquire science knowledge. Fourth, Korean students were shown to participate very little in out-of-school scientific activities other than watching TV programs related to science. Whatever the activities may be, the more actively involved students are in out-of-school scientific activities, the higher their scientific literacy achievement. Fifth, Korean girls were rather passive compared to boys in all areas, including science learning motive and out-of-school scientific activities. The gender difference was especially more pronounced in out-of-school scientific activities with wider gaps in such activities as reading scientific books or articles and visiting science-related web sites.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.507-512
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• 2001

The government set up a comprehensive plan for EC vitalizations in February 2000 and has begun implementing it. They hope to introduce EC into the economy at large and invoke reconsideration of its efficiency and transparency in the public sector. To accomplish this, the government has built EC utilization system within the industry and trade. However, the overall EC in the construction industry is below expectation. With the aid of the government, larger construction companies are building E-marketplace by increasing the investment in IT and organizing a consortium. On the other hand, small and medium construction companies have difficulties in investing in EC. On the basis of a field research, this study investigates problems that small and medium construction industry confronts in a domestic environment and EC system. It also analyzes the limitations of the tax reduction law for EC. Therefore, this study suggests a counterplan that defines the importance of a government guided plan and necessity of providing incentives to encourage EC Utilization degree.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.5998-6008
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• 2015

The value of social network and entrepreneurial orientation has widely been acknowledged as a critical resource of business success. However, the previous studies did not specify each role and conceptually have examined them as separate antecedents of firm performance. This study develops propositions concerning network capabilities and investigates the moderating effects of network structures (degree centrality, closeness centrality, and betweenness centrality) on the relationship between entrepreneurial orientation and firm performance. This research conducted with a sample of 115 small consulting companies in Korea. The findings indicate that closeness centrality moderates the relationship between proactiveness and performance. Also, the combination of betweenness centrality and proactiveness exerts a positive impact on performance. Accordingly, degree centrality enhances the influence of innovativeness on performance. In particular, betweenness centrality exacerbates the influence of risk-taking on performance against our expectation. Overall, these findings conclude the synergistic effects of network capability and entrepreneurial orientation on firm performance. Finally, practical implications and academic propositions are presented regarding the way firms could most effectively utilize entrepreneurial orientation and network capability to maximize firm performance.

• International Area Studies Review
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• v.15 no.3
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• pp.393-405
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• 2011

Three different models have been consecutively employed with the U.S. yield curve and the Korean composite stock price index, firstly to see the coupling between the economies of the U.S. and Korea, secondly to find out the time consumed completing the coupling, and lastly to figure out the impact of the recent U.S. financial crisis on this coupling. This study has, first of all, produced an empirical research outcome which proved the existence of coupling between two countries' economies. The direction of this coupling was consistent with the general expectation that when the yield spread between the U.S. 10-year Treasury Note and the U.S. 3-month Treasury Bill increased which often occurred with better prospects of U.S. economy, the asset price of emerging economies including Korea also rose reflecting the accompanying change in investment atmosphere in favor of risk. It has also found out that the degree of the coupling was maximized with a lag of one week. And finally the recent US financial crisis has been revealed to reduce the degree of the coupling by as much as half in a regression model with a dummy variable.