• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.201-210
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• 2018

This paper proposes a new start-up method for a load commutated inverter (LCI) in a large synchronous gas-turbine generator. The initial rotor position for start-up torque is detected by the proposed initial angle detector, which consists of an integrator and a phase-locked loop. The initial rotor position is accurately detected within 150ms, and the angle difference between the real position and the detected position is less than 1%. The LCI system operates in two modes (forced commutation mode and natural commutation mode) according to operating speed range. The proposed controllers include a forced commutation controller for the low-speed range, a PI speed controller and a PI current controller, where the forced commutation controller is connected to the current controller in parallel. The current controller is modeled by Matlab/Simulink, where a six-pulse delay of the thyristor and a processing delay are considered by using a zero-order hold. The performance of the proposed start-up method is evaluated in Matlab/Psim at standstill and at low speed. To verify the feasibility of the method, a 5kVA LCI system prototype is implemented, and the proposed initial angle detector and the system performance are confirmed by experimental results from standstill to 900rpm.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.117-128
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• 2018

Various government support policies are being promoted in order to stimulate growth of SMEs. The government is striving to provide effective support through direct methods of tax, finance and indirect methods through support programs. However, the view on the government's startup policy is still tense. We are sympathetic with the need for support, but discussions continue to be made on the effectiveness of support projects and support projects. Therefore, this study evaluates the importance and satisfaction of the government start-up support project. For this purpose, we conducted questionnaires on ICT start-ups who have experienced government start-up support projects. Of these, 128 were analyzed for GAP analysis and ISA. As a result of the GAP analysis of the government start - up support project, the degree of satisfaction (4.408) was lower than the degree of importance (5.221), confirming that the beneficiary's evaluation on the start-up support project was negative. As a result of the importance-satisfaction analysis, 'R&D' and 'commercialization' are located in the maintenance area, and 'government funding', 'marketing, overseas advancement' projects are included in the concentrated area. In the low-ranking areas, there are 'entrepreneur events and networks' items. Finally, there are 'facilities and spaces', 'mentoring and consulting', and 'entrepreneurship education' in the surplus areas. As a result of multiple regression analysis, it was found that 'R&D', 'entrepreneurial education', and 'government funding' influenced satisfaction. Based on the results of this study, it is expected that it will contribute to improving the quality level of the government start-up support project by establishing the support policy for the ICT start-up enterprises and improving the system.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.2
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• pp.95-104
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• 2019

Fear to start-up failures has been known to have a negative impact on entrepreneurial intention. This is one of the reasons why the government adopts a policy to help university students overcome their fear of start-ups. Setting educational goals to foster innovative and progressive entrepreneurs, universities have been conducting entrepreneurship education, but it is hard to say that constructive results have been achieved so far. Rather than adopting the practice of optional entrepreneurship education, there is a need to have all university freshmen mandatorily take the course of entrepreneurship education. This study aims to uncover the impact of more aggressive entrepreneurship education position in the university by analyzing empirical data. The relationship between an entrepreneurship level and entrepreneurial intention was tested, and start-up fear was also considered. In the research model, self-leadership and self-efficacy were included as regressors to entrepreneurship levels. Especially, this study tested moderate effects of start-up community during the course. The results from the sample of 2,500 freshmen indicate that entrepreneurship level is significantly improved by taking the course; however, fear to start-up failures remains still. In addition, empirical findings show that putting start-up communities in the entrepreneurship education helps students by moderating self-leadership and self-efficacy. This study extends our knowledge of entrepreneurship education in university by analyzing university freshmen data empirically.

• Journal of the Korea Convergence Society
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• v.12 no.2
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• pp.163-171
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• 2021

The purpose of this study is to examine the current operation condition of fashion start-up companies and the characteristics of their founders in Fashion Creative Studio that is one of government programs supporting fashion start-up of rising fashion designer's brands in Korea and one of supporting facilities. For this purpose, this study surveyed 32 fashion start-up companies founders in Busan Fashion Creative Studio and analyzed the data based on the survey. The results are as follows. First of all, 82% of the founders have experience to start their business in 20s and 60% of founders with not more than 3 to 5 years of work experience related to fashion challenge to start a business. Secondly, major distribution channels of the fashion start-up companies are mainly on-line open-market consisting of 36% and SNS is up to 80% as the main promotion method. In addition, exports to China account for 71% of all exports. Lastly, 33% of businesses consider viral marketing by influencer and 50% of them make plan to export their items to East Asia. It is of research significance that this study can suggest the successful direction of establishing and operating fashion start-up companies through making good use of Fashion Creative Studio, the supporting program including facility.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.113-120
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• 2013

This study aimed to obtain quantitative data for WWTP operators in phosphorus removal process. This was done by reviewing and comparing phosphorus removal efficiency(%), coagulants dosage(Al/P and $Al_2O_3$(mg/L)), sludge production($kg/m^3$), and operation cost($won/m^3$) of start-up and normal operation data. Phosphorus removal efficiency of all tertiary treatment process was up to 70 ~ 89 % in start-up and normal operation. Average molar ratio(Al/P) was similar as 5 in both operations, but average coagulants dosage (mg/L) of start-up (8.5 mg/L) was higher than normal operation (6.2 mg/L). Average operation cost was higher for start-up ($33.6won/m^3$) than normal operation ($28.4won/m^3$), while electricity cost required for the normal operation ($9.0won/m^3$) was higher by $3.5won/m^3$.

• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.60-70
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• 1997

Since, human error is a major factor contributing to disaster during start-up of operation in Boiler plant. it is necessary to develop an automation system which prevent mode of operation that are known to be dangerous and to bring a loss of energy. The aim of this study is to suggest a model for the computer-aided synthesis of operation sequence as a part of automation system for start-up operation. Synthesis is accomplished by the formation of a hierarchical network of goals which decide sequence of operations. Hierarchical Network is formed by using method which upper goals ( i.e. upper operation al situation) are classified by the function of themselves into lower goals (i.e. lower operational situation). Knowledge for deciding operation sequence is generated by putting In order the knowledge of hazard operation and energy management.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.3
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• pp.408-415
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• 1998

This study presents experimental results on the shut-down and start-up characteristics of a residential split-system air-conditioner with capillary tube, using R410A as a R22 alternative refrigerant. During shut-down, the transient characteristics are evaluated by measuring the high side and low side pressures and temperatures of the system. The dynamic behavior of the system after start-up is also investigated at the high temperature cooling test condition. All experiments are performed in psychrometric calorimeter. The cooling capacity, power consumption, dehumidification capacity and cycle characteristics after start-up are analyzed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.2
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• pp.104-110
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• 2016

The process of three-dimensional (3D) printing (also known as "rapid prototyping" and "additive manufacturing") uses computer-created digital models to produce 3D objects with a desired shape by stacking materials through a layer-by-layer process. The industrial potential and feasibility of 3D printing technology were recently highlighted in President Obama's State of the Union address in 2013. Since his speech, worldwide investment in and attention toward 3D printing technology have increased explosively. In addition, a number of 3D printing technology-based start-up companies have been established and evaluated as emerging enterprises making successful business models. In this paper, successful start-up companies (domestic and overseas) based on 3D printing technology will be reviewed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.34-37
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• 2010

One dimensional transient analysis was studied for turbopump-fed liquid propellant rocket engine(LRE) system in starting using AMESim. The effects of timing of gas generator fuel valve opening and gas generator ignition to start-up stability were researched for open cycle type system using LOX/RP-1 to propellants. Result show that the parameters and sequence on start-up should be considered to design optimized turbopump-fed LRE system.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.1
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• pp.101-116
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• 2019

Technology-based start-up is important in that it encourages innovation, facilitates the development of new products and services, and contributes to job creation. Technology-based start-up activates entrepreneurship when appropriate support is provided within the ecosystem. Thus, understanding the technology-based start-up ecosystem is crucial. The purpose of this study is as follows. First, in Herrmann et al.'s(2015) study, we compare and analyze the ecosystem of each country by selecting representative regions such as Silicon Valley, Tel Aviv, London and Singapore which have the highest ranking in the start-up ecosystem. Second, we try to deeply understand the start-up ecosystem based on in-depth interviews with various stakeholders such as VC investors, start-ups, support organizations, and professors related to the Korean start-up ecosystem. Finally, based on the results of the study, we suggest development and activation of Korean technology-based start-up ecosystem. As a result, the Seoul start-up ecosystem showed a positive evaluation of government support compared to other advanced countries. In addition, it was confirmed that the ratio of tele-work and start-up company working experience of employees was higher than other countries. On the other hand, in Seoul, It was confirmed that overseas market performance, human resource diversity, attracting investment, hiring technological engineers, and the ratio of female entrepreneurs were lower than those of overseas advanced countries. In addition, according to the results of the interview analysis, Seoul was able to find that start-up ecosystems such as individual angel investors, accelerators, support institution, and media are developing thanks to the government's market-oriented policy support. However, in order for this development to continue, it is necessary to improve the continuous investment system, expansion of diversity, investment return system, and accessibility to the global market. A discussion on this issue is presented.