• Advances in concrete construction
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• v.17 no.1
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• pp.13-26
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• 2024

Due to its capacity to address urgent environmental challenges connected to urbanization and stormwater management, pervious concrete, a sustainable and innovative material, has attracted a lot of attention recently. The aim of this study was to find the engineering characteristics of pervious concrete made from recycled aggregate (RA) at various aggregate-to-cement ratios (A/C) and the addition of 5% (by weight of total aggregate) of both natural and recycled fine aggregate to produce a very sustainable concrete product for a variety of applications. The three distinct aggregate-to-cement ratios, 6, 5, and 4, were used to produce pervious concrete using recycled aggregate in the research approach. The ratio of water to cement (w/c) was maintained at 0.3. Pervious concrete was created using single-sized recycled aggregate that passed through a 12.5 mm sieve and was held on a 9.5 mm sieve, as well as natural and recycled sand that passed through a 4 mm sieve. The production of twelve distinct concrete mixtures resulted in the testing of each concrete sample for dry density, abrasion resistance, compressive and splitting tensile strengths, porosity, and water permeability. A statistical method called GLM-ANOVA was also used to assess the characteristics of pervious concrete made using recycled aggregate. According to the experimental results, lowering the aggregate-to-cement ratio enhances the pervious concrete's overall performance. Additionally, a modest amount of fine aggregate boosts mechanical strength while lowering void content and water permeability. However, it was noted that such concretes' mechanical qualities were adversely affected to some extent. The results of this study offer insight into the viability of using recycled aggregates in order to achieve both structural integrity and environmental friendliness, which helps to optimize pervious concrete compositions.

• Steel and Composite Structures
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• v.53 no.1
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• pp.29-43
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• 2024

In this paper, the behavior of an innovative metallic a butterfly-shaped link as damper with shear and flexural mechanism was investigated experimentally and numerically. The damper is directly attached to the diagonal member of the Concentrically Braced Frame (CBF) to prevent buckling of the braces. Since it is expected that nonlinear behavior of the system is limited to the dampers, the other parts of structures remind elastic that the damper can replaced easily after a severe earthquake. The experimental outcomes indicated that both types of dampers (with shear or flexural mechanism) pertain to stable hysteresis loops without any significant degradation in stiffness or strength. Comparing the dampers indicated that the shear damper has a greater ultimate strength (4.59 times) and stiffness (3.58 times) than flexural damper but a lower ductility (16%) and ultimate displacement (60%). Also, the shear damper has a considerable dissipation energy 14.56 times greater than flexural dampers where dissipating energy are affected by ultimate strength, stiffness and ultimate displacement. Also, based on the numerical study, the effect of main plate slenderness on the behavior of the damper was considered and the allowable slenderness was suggested to the design of the dampers. Numerical results confirmed that the flexural damper is more sensitive to the slenderness than shear damper. Accordingly, as the slenderness is less than 50 and 30, respectively, for, shear and flexural damper, no degradation in ultimate strength is realized. By increasing the slenderness, the maximum reduction of the ultimate strength, stiffness, and energy dissipation capacity reached by 16%, 7%, and 17% for SDB dampers whereas it is 3%, 33%, 20%, and 45% for MDB.

• The Journal of the Korea Contents Association
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• v.11 no.6
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• pp.326-336
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• 2011

The Purpose of this study was to examine effects of mentoring function on career development and organizational effectiveness in private security service organization. Example number used on interpretation finally using purposive sampling method after this study establishes 5 places private security service company's security guard by population in Seoul on March, 2010 is total 227 people. Reliability of questionnaire appeared Cronbach's ${\alpha}$ value more than .667. Conclusions that appears in this study is as following. First, private security service organization's Mentoring function affects in career development. That is, if friendship, patronage, career management, society mind, and role model are mobilized, innovative own development, special capacity development, and information competitive power development are helped. Second, private security service organization's Mentoring function affects in organization effectiveness. If friendship, patronage, career management, society mind, and role model are mobilized, career satisfaction, organization immersion, and job satisfaction increase. On the other hand, change of jobs intention decreases if function of society mind is mobilized. Third, private security service organization's career development affects in organization effectiveness. If reform and special capacity development are helped, career satisfaction, organization immersion, and job satisfaction increase. While change of jobs intention decreases as development of information competition is helped. Fourth, Mentoring function exerts influence of causality on career development and organization effectiveness. That is, Mentoring exerts direct influence on organization effectiveness, but it exerts indirect effect through career development.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.679-688
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• 2000

Dispersants, which are used to break water-in-oil emulsions and to remediate oil-spills, are another water pollutants. In this study, magnetic separation technology was applied to remove dispersants from the sea. Magnetite and maghemite were used as magnetic sorbents and SDDBS, an anionic surfactant and Triton X-100, a nonionic surfactant, were employed as dispersants. Batch experiments were undertaken to study the sorption capacity and sorption equilibrium, and water-bath experiments were conducted to simulate the real situation and to describe the recovery of magnetic particles by the permanent magnet or electromagnet. Maghemite has rather constant removal efficiency for dispersants, regardless of surfactant species. On the other hand, removal efficiency by magnetite is higher for anionic surfactant than maghemite and is higher in distilled water than in seawater which contains more ions. The sorption of dispersants to magnetite is explained by electrostatic attraction and that of maghemite is described not only by electrostatic attraction, but also by structural characteristics that provide high sorption ability and surface condition. Water bath experimental results showed that recovery efficiency of magnetic particle after sorption for dispersants is nearly 100%. It is suggested that this magnetic separation technology is an effective way of dispersant removal because of short operating time, high sorption capacity, and high recovery efficiency of sorbents.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.737-742
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• 2017

Recently, unconventional high-rise building shapes have attracted attention as a landmark of metropolitan cities and the search for innovative building forms in architecture is ongoing. In this study, $Isotruss^{(R)}$ grid(ITG) used in smaller scale structures was applied to building structural systems and its structural performance was examined. The structural behavior of an ITG was compared with that of a diagrid structure as a reference structure. The stiffness-based design method of the diagrid system was used for the preliminary design stage of member sizing in an ITG. The structural design of 16, 32, and 48-story buildings was carried out for the two systems with the same size. The angle of the inclined columns for ITG and diagrid was $59^{\circ}$ and $68.2^{\circ}$, respectively. The lateral stiffness, steel tonnage of the exterior frame, axial strength ratio, story drift ratio, and natural frequency of the two systems were compared. Based on the analysis result of 6 buildings, the two systems had similar structural capacity; 93.3% and 88.7% of the lateral load was carried by the perimeter frame in the ITG system and diagrid system, respectively. This suggests that the ITG system is better in arranging core columns. Therefore, the proposed ITG system has not only a unique façade, but also substantial structural capacity equivalent to the existing system.

• 한국벤처창업학회:학술대회논문집
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• 2017.08a
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• pp.1-13
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• 2017

In the era of the 4th Industrial Revolution, as the importance of creative talent became more and more important, we recognized the urgent need for start-ups to innovate new growth industries and creative talents to lead these eras.And the importance of entrepreneurship education emphasized in entrepreneurship education and the necessity of creativity competency education.However, there is a lack of research on how creativity competency education affects entrepreneurship intention for college students. Especially, research on the moderating effect of social support on the effect of entrepreneurship through education is very insufficient. The purpose of this study is to examine the effects of creativity competence education on the will of entrepreneurship and empowerment of social support. For this purpose, 393 college students were used for empirical analysis for 1 month from August 2016. As a result of this study, the ability of communicative communication and creative problem solving had a positive effect on self - efficacy. On the other hand, innovative work behavior abilities did not directly affect self-efficacy. In addition, creative problem solving ability and innovative work behavior ability had a positive effect on the will to start up. Collaborative communication skills, however, did not directly affect the willingness to start a business. Self - efficacy has a positive effect on the will of founding. Finally, the moderating effect of social support between self-efficacy and willingness to work was not directly affected. The implication of this study is that the effect of the creativity competency education on college students has a positive effect on the self - efficacy of self and the positive influence on the will to start up. The results of this study are as follows. First, it is found that the influence of social support (parental support) is not positively influenced by the control effect of the parents. In the case of college students, As well as the need to do so. Therefore, in order to further increase the willingness of young people to establish a university in the university, it is necessary to provide education and programs not only for direct education for college students, but also for improving the understanding of the talents and entrepreneurship required by the age of their parents.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.5
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• pp.245-259
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• 2020

The development of technology and the advent of a non-face-to-face society are expected to have a direct impact on job problems. In line with this phenomenon, the government and education and training institutions are coping with job problems through the start-up support policy while at the same time inducing the creation of innovative companies. In particular, youth start-up support can be expected not only to compensate for market failures, but also to promote high-growth start-ups. Based on this background of research, this study examined the competency of young entrepreneurs to start their own businesses, their entrepreneurial self-efficacy, and their impact on success and satisfaction of start-ups. Based on the theoretical research, the research theory and research model were derived by setting entrepreneurial self-efficacy as a mediating variable after reviewing the relation between the main elements of start-up competency of young start-up entrepreneurs and start-up performance. The Youth Entrepreneurship Competency was divided into four categories: Entrepreneurial Competencies, Technical Competencies, Management Competencies, and Creative Competencies, and the hypothesis was that each had a significant impact on the start-up performance through the mediating effect of entrepreneurial self-efficacy. A survey was conducted on young entrepreneurs in their 20s and 30s in Korea for empirical research, and the analysis results were as follows. First of all, the competency of young entrepreneurs to start their own businesses affects the success of start-ups and the satisfaction of start-ups. There are differences in the competencies, and both technical and management competencies can be seen through the entrepreneurial self-efficacy to enhance the success of start-ups and the satisfaction of start-ups. Entrepreneurial competency was fully mediated to start-up success and partially mediated to start-up satisfaction. In the case of creative competency, there were only direct effects on successful start-ups, and the satisfaction of start-ups showed partial mediating effects. Thus, seven of the eight detailed hypotheses were supported and one was rejected. Based on the above findings, the implications were presented.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.1
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• pp.61-72
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• 2018

In a rapidly changing environment, such as globalization, technology-based startups are attracting attention as a new growth engine that creates jobs and added value and promotes national competitiveness. At present, countries around the world recognize the development of technology-based start-up companies as a major policy task and strive to make policy efforts to revitalize start-ups and strengthen innovation capabilities of companies. Especially, in order to secure superiority in the fierce market competition, it is becoming more and more important for the growth and development of technological start-up companies that pioneer new markets and energize the economy based on original and innovative technologies. Therefore, it is necessary to study systematically and plan for survival and growth of technology start-up companies. The purpose of this study is to investigate the entrepreneurial spirit of Innovation, Entrepreneurship, Risk Sensibility and Technology Innovation Capacity, R&D ability, Technology Accumulation Capacity, Technology Innovation System, The results of this study are as follows. the effects of marketing ability on technical performance and financial performance are examined. First, the CEO 's entrepreneurial spirit has an effect on the technical performance and financial performance of the management performance. Second, the technology accumulation ability and the R & D capability have a positive effect on the technical performance. Finally, it was found that the ability to commercialize the technology commercialization capacity affects both technical performance and financial performance. The policy implications that can be gained through this are as follows. First, by strengthening cooperation between universities and research institutes, related technology entrepreneurship education programs should be upgraded so that technology entrepreneurs or preliminary entrepreneurs can capture business opportunities and secure market price competitiveness. Secondly, R & D for the purpose of start-up should be developed and marketable technology should be developed and linked to direct start-up. Third, it is necessary to activate the program to match the company with the honorary retirement manpower of large enterprises and SMEs, which have more experience in field experience than the founders.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.6
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• pp.25-39
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• 2017

The role of traditional universities has been emphasized as a career path to advance into society. Recently, it has become a new paradigm of university education by emphasizing entrepreneurship as a career aspect. While entrepreneurship education is constantly expanding for college students, relatively few young people choose to start their own business. Despite the fact that the government is continuing to expand the university's entrepreneurship education, there are very few achievements that lead to actual entrepreneurship and student start-up There is still a lack of research on ways to cultivate creative talents and increase practical entrepreneurial intention. The results of this study are as follows: First, the effects of creativity competency education on self-efficacy and entrepreneurial intention were analyzed. The effect of self-efficacy on the entrepreneurial intention. Finally This study examined the effects of social support (parent support) between self-efficacy and entrepreneurial intention. This study used 393 samples in August 2016 for university students who received entrepreneurship education. The results showed that the ability of communicative communication and creative problem solving had a positive effect on self-efficacy. On the other hand, innovative work behavior abilities did not directly affect self-efficacy. In addition, creative problem solving ability and innovative work behavior ability had a positive effect on the entrepreneurial intention. On the other hand, the ability to communicate in a collaborative manner has no direct effect on the entrepreneurial intention. In addition, self-efficacy has a positive effect on the entrepreneurial intention. Finally, the adjustment effect of social support (parent support) between self-efficacy and entrepreneurial intention has no effect. The implications of this study are empirically verified the effectiveness of creativity capacity through entrepreneurship education and the result of meaningful research that the social support through cooperation of parents is indispensable in order to increase the actual starting will of college students. Therefore, universities need to establish entrepreneurship education programs for their parents in order to increase the willingness of college students to start-up. This study can be used as a meaningful basic data for establishing policy for student start - up and suggesting the right direction of entrepreneurship education.

• Journal of Science and Technology Studies
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• v.6 no.1 s.11
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• pp.1-30
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• 2006

This paper is to analyse the case of citizen participation employed in the local government, Buk-gu (Northern District) in the city of Ulsan, Korea. A kind of deliberative type of citizen participation named' citizen jury' was exercised to resolve an environmental conflict between Buk-gu government and its residents. The conflict was caused by the construction of a food waste recycling facility near by some residential areas in Buk-gu. Theoretically this paper makes a typology of citizen participation methods. Two criteria are employed. First of all, lay citizens are the primary participant or not? Secondly, interactive communication is feasible or not among participants in the process of citizen participation. Four generic types of citizen participation are sorted out: technocratic, pluralist, direct/participatory, and deliberative type. Especially deliberative type of citizen participation is based on an idea of deliberative democracy. This paper argues that the case of citizen participation employed in Buk-gu belongs to deliberative type of citizen participation. The argument is based on the following reasons. Firstly, primary participants in deliberation process can be considered as lay citizens though they are selected form local NGOs and religious groups. According to a survey, most of participants said that they would participate in the process of deliberation in the capacity of lay citizens though they were selected by their own groups. Secondly, the citizen participation process was deliberately designed and implemented to facilitate competence of primary participants and fairness in the deliberation. Viewed from this analysis, this Buk-gu case can be safely considered an innovative method of citizen participation which is also very successful in resolving intractable environmental conflict in the local government.