• Transactions of the Korean hydrogen and new energy society
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• v.24 no.2
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• pp.99-106
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• 2013

The variations of performance and metabolites at an early stage were investigated for the successful start-up technology in continuous fermentative hydrogen production. Unsuccessful start-up was observed when the operation mode was changed from batch to continuous mode after the yield was reached to 0.5 mol $H_2$/mol $hexose_{added}$ by batch mode. $H_2$ production continued till 12 hours accompanied by butyrate production, but did not last with propionate production increase. It was suspected that the failure was due to the regrowth of propionic acid bacteria during batch mode which were inhibited by heat-shock but not completely killed. Thus, successful start-up was tried by early switchover from batch to continuous operation; continuous operation was started after the $H_2$ yield was reached to 0.2 mol $H_2$/mol $hexose_{added}$ by batch mode. Although $H_2$ production rate decreased at an early stage, stable $H_2$ yield of 0.8 mol $H_2$/mol $hexose_{added}$ was achieved after 10 days by lowering down propionate production. And it was also concluded that the reason for $H_2$ production decrease at an early stage was due to alcohol production by self detoxification mechanism against VFAs accumulation.

• Journal of Engineering Education Research
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• v.8 no.1
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• pp.71-83
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• 2005

This paper presents an internet-based self-learning educational system which can be enhancing efficiency in the learning process of Java language. The proposed self-learning educational system is called Java Web Player(JWP), which is a Java application program and is executable through Java Web Start technologies. Also, three important sequential learning processes : concept learning process, programming practice process and assessment process are integrated in the proposed JWP using Java Web Start technologies. This JWP enables the learners to achieve efficient and interesting self-learning since the learning process is designed to enhance the multimedia capabilities on the basis of various educational technologies. Furthermore, internet-based on-line voice presentation and its related texts together with moving images are synchronized for efficient language learning process. Also, a simple and useful Java compiler is included in the JWP for providing language practice environment such as coding, editing, executing and debugging Java source files. Finally, repeated practice can make the learners to understand easily the key concepts of Java language. Simple multiple choices are given suddenly to the learners while they are studying through the JWP and the test results are displayed on the message box. This assessment process is very essential to increase the learner's academic capability.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.1
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• pp.139-146
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• 2021

This study studied the network between positive psychology capital, intention of start-up, and start-up behavior for learners who are willing to start a business. The research targets were intended to study the impact of the connection relationship between each variable, targeting nail art certification learners who are willing to start their own businesses. For this study, the measurement variables of positive psychology capital, intention of start-up, and start-up behavior were set, and the collected data were analyzed for connection-centeredness and eigenvector after data collection. The findings are as follows. First, some variables affecting the intention of start-up showed optimism, resilience and hope of positive psychology capital. Second, the intention to start a business was shown to have a significant impact on the behavior of start-ups, which, unlike the preceding study, appeared to be almost outside the network structure, showing that the behavior of start-ups was not significantly affected by other variables. Third, it is important to increase self-efficacy in positive psychological capital in order to increase the behavior of start-ups. Fourth, the analysis of the eigenvactor among positive psychology capital, intention of start-up, and start-up behavior showed optimism as some of the most central variables. In other words, prospective start-ups were found to be aware of the hardships and expected positive results in the future. The implications of this study, along with the intention and behavior of prospective entrepreneurs, are important factors in positive psychology capital, and suggest the importance of various educational programs that can be enhanced by positive psychology capital in start-up education or training programs and what should be taught. In addition, this study analyzed the network by approaching it from the perspective of positive psychology capital of prospective entrepreneurs in order to enhance the effectiveness of support programs for start-ups by the government, public institutions or universities in the future.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2540-2542
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• 2003

This paper presents an internet-based self-learning educational system which can be enhancing efficiency in the learning process of Java language. The proposed self-learning educational system is called Java Web Player(JWP), which is a Java application program and is executable through Java Web Start technologies. In this paper, three important sequential learning processes : concept learning process, programming practice process and assessment process are integrated in the proposed JWP using Java Web Start technologies. This JWP enables the learners to achieve efficient and interesting self-learning since the learning process is designed to enhance the multimedia capabilities on the basis of educational technologies. Also, online voice presentation and its related texts together with moving images are synchronized for efficient language learning process. Furthermore, a simple/useful compiler is included in the JWP for providing language practice environment such as coding, editing, executing and debugging Java source files. Finally repeated practice can make the learners to understand easily the key concepts of Java language. Simple multiple choices are given suddenly to the learners while they are studying through the JWP and the test results are displayed on the message box.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.9
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• pp.1119-1124
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• 2018

So far BESS(Battery Energy storage system) has been widely applied to power systems rapidly. Usually it has been used to regulate the renewable energy output and to adjust the power system frequency. In 2013, EPRI has reported a study of utilizing BESS to replace two black start generators of American Electric Power(AEP) that will be demolished. If the BESS can be used as a self-starting generator, it is possible to shorten the long-distance primary transmission line and shorten the restoration time because BESS is capable of the high-speed start and there is no restriction on the installation position. This paper presents a possibility of using BESS as a self-starting generator by using PSCAD/EMTDC in Korean power systems. Herein, the process to estimated the required capacity of BESS is also presented.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.2
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• pp.35-49
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• 2021

The purpose of this study is by using the Grounded Theory method to examine the process of starting a business in an online shopping mall for young self-employed people with experience in using Company N's Partner Square (Gwangju), a startup infrastructure institution. In this study, in-depth interview survey data were used, and theoretical sampling method was used in the selection of study participants. After proceeding in the order of open coding, axis coding, and selective coding suggested by Strauss & Corbin, it was analyzed with a paradigm model. The main research results are as follows. First, even when parents were unaware about online shopping malls or had a negative mindset about it, but they had a positive mindset about their children's start-ups, it was found that their children tended to start online shopping mall businesses. However, if parents had a negative mindset about online shopping malls and about their children's start-up, then the child could not start an online shopping mall business. Second, it was found that the ability to use online shopping malls is important as a condition for entrepreneurship and achievement in online shopping malls for young people. In particular, Partner Square (Gwangju) was found to increase the ability to use online shopping malls and positively influence startups in online shopping malls. Third, it was found that young people have increased their self-esteem, discovering opportunities, and reinforcing their creativity, in addition to simply increasing their sales after starting the online shopping mall.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.234-251
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• 2022

In this study, effects of the psychological characteristics of office workers and start-up preparation on entrepreneurship intention by mediating entrepreneurial opportunity recognition were analyzed. As sub-variables of psychological characteristics, desire for economic achievement, self-fulfillment, and risk-taking tendencies were classified. The collected 357 questionnaires, SPSS v24.0 and Process macro 3.5 were used for empirical analysis. As a result, first, it was showed that self-fulfillment and start-up preparation had a positive (+) effect on entrepreneurial intention, and the effect of desire for economic achievement and risk-taking tendencies on entrepreneurial intention was not significant. Second, it was confirmed that psychological characteristics and start-up preparation had a significant positive (+) effect on the entrepreneurial opportunity recognition. Third, it was found that the effect of the entrepreneurial opportunity recognition on the entrepreneurial intention was significant in the positive (+) direction. Fourth, entrepreneurial opportunity recognition was tested as mediating the psychological characteristics of workers, start-up preparation and entrepreneurial intention. As a follow-up study, it is recommended that studies to analyze moderated mediating effects by the conditional process model including moderating variables and to discover the third mediator other than a mediator used in the research should be conducted.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.539-541
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• 2022

Due to the prolonged covid-19 pandemic, the rate of closure of the self-employed is rapidly increasing, and the economic damage is increasing. In this study, we provide various information such as the degree of overcrowding by region and industry through the analysis of business districts in Chungcheongbuk-do due to the outbreak of covid-19, and analyze the start-up environment by using public data to help start-up success and business stability. It provided support for self-employed people to use as basic data when starting a business.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.1
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• pp.14-17
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• 2007

Power system restoration following a massive blackout starts with re-energizing primary restorative transmission systems at first. The comparison of the TLCC(transmission line charging capacity) and the RPC(reactive power capability) of related black-start generator should be considered in this stage because overvoltage can be caused by self-excitation at the generator when the RPC is smaller than the TLCC. The RPC can be decided by two criteria. One is stator end core heating, and the other is steady state stability. RPC in steady state stability area has been found based on a synchronous reactance Xd. This paper presents RPC limit of salient pole machine which is different from that of non-salient pole machine in steady state stability area and shows derivation process about that.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.339-343
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• 2006

Model SCRamjet Engine intake is designed for Ground test. The designed Intake provides hot and slow flow with the combustor. Flow separation is controlled by the shock wave segregation based on the Korekegi criteria. With Kantrowitz limit analysis, side wall cut out region is also set for the self start.