• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1371-1376
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• 2003

In the thermal power plant, the main steam temperature is typically regulated by the fuel flow rate and the spray flow rate, and the reheater steam temperature is regulated by the gas recirculation flow rate. However, Strictly maintaining the steam temperature can be difficult due to heating value variation to the fuel source, time delay changes in the main steam temperature, the change of the dynamic characteristics in the reheater. Up to the present time, PID Controller has been used to operate this system. However, it is very difficult to achieve an optimal PID gain with no experience, since the gain of the PID controller has to be manually tuned by trial and error. This paper focuses on tuning of the 2-DOF PID Controller on the DCS for steam temperature control using immune based multiobjective approach. The stable range of a 2-DOF parameter for only this system could be found for the start-up procedure and this parameter could be used for the tuning problem. Therefore tuning technique of multiobjective based on immune network algorithms in this paper can be used effectively in tuning 2-DOF PID controllers.

• Journal of Information Display
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• v.11 no.2
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• pp.39-44
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• 2010

The time dependences of the luminance properties of 55-inch CCFL and LED backlights and 32-inch FFL backlights with LCD panels were investigated during the warm-up time from the cold start. The long-term luminance maintenance curve of a standard CCFL was examined in a time window up to 5000 hours. These two time dependences are important characteristics from the viewpoint of initial picture quality and lifetime reliability, respectively. Empirical equations were suggested for the analysis of the time dependence of these luminance data. These approaches are expected to be helpful in predicting the luminance properties of backlights based on the luminance data obtained in a limited time window.

• Journal of Distribution Science
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• v.12 no.12
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• pp.119-130
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• 2014

Purpose - Franchise industries are significant both socially and economically. However, with increasing interest, there are manifold problems. It is necessary to seek measures for mature operation constantly despite unprepared franchisors, negative perceptions of the media and society toward franchise, and rapid changes in business start-up trends and propensity to consume that make business start-ups difficult. The paper aims to explain the effects of relational commitment and performance on the franchisor's management characteristics and justice in the food service franchise system. Research design, data, and methodology - This is an exploratory survey examining franchising in Korea. Based on a literature synthesis, we extract five constructs: managerial characteristics, support, fairness, trust, and satisfaction. We hypothesize that these factors influence the trust, satisfaction, and performance of franchisees. To examine these hypotheses empirically, we conducted a survey on the database of the Franchising Council of Korea. The study employs data from May to September 2014. In total, 135 completed questionnaires were received, of which 128 were usable. The data was analyzed with SPSS/PC 22.0. First, to test unidimensionality and nomological validity of the measures of each construct, we employed a scale refinement procedure. The result of a reliability test with Cronbach's α and factor analysis warranted unidimensionality of the measures for each construct. In addition, nomological validity of the measures was warranted from the result of the correlation and regression analysis. By analyzing the data, we can confirm most hypotheses. Results - Frist, franchisor characteristics have a positive effect on trust and satisfaction. Second, franchisor fairness has an effect on trust and satisfaction. Third, franchisor support has an effect on satisfaction. Further, the franchisee trust has an effect on satisfaction. Fourth, the satisfaction of a franchisee with a franchisor affects the performance of a franchisee. Finally, there is a possibility that not only franchisee performance but also increasing the credibility and improving the image of the franchisor through communication between franchisor and franchisee can improve franchisees' performance and satisfaction by motivating the franchisee for sustainable growth. Franchisers should endeavor for franchisees to obtain stable revenue with continuous and practical support. They should recognize that they can expand their business by supporting their franchisees. Franchisors should not only instantly respond to franchisees' troubles with interactive communications but also raise the ability of supervisors for better support. Franchisors should share their visions and goals with their franchisees and provide systematic and continuous support based on trust and clear company management. Franchisees should understand franchisors' position as well as participate in establishing the basic franchise system. Contributions - The paper contributes to understanding franchising in Korea. It offers insights and assistance to franchisors hoping to start franchises. This paper explores measurement issues related to franchisee performance by estimating its determinant factors (managerial characteristics, support, fairness, trust, and satisfaction). This study provides franchisors and practitioners planning to extend their franchising business with some practical knowledge.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.497-511
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• 2019

The purpose of this study is to examine the effects of entrepreneurship and personal characteristics on entrepreneurial intention and to analyze what factors influence the entrepreneurial intention through the moderating effects of social networks. So, the survey was conducted on 374 employees in their 30s or older. Descriptive statistics were used to understand the actual state of entrepreneurial intentions, and exploratory factor analysis was conducted to analyze the validity. In addition, a correlation analysis was conducted to identify relationships with variables, finally, a hierarchical regression analysis was performed to identify the effect of moderating social networks in entrepreneurship and personal characteristics. The study found that, firstly, Entrepreneurship was positively correlated with extroversion, achievement desire, self-efficacy, social network, entrepreneurial intention, and negatively correlated with introversion. Second, The extroversion of personal characteristics showed positive correlations with achievement desire, self-efficacy, social network, and entrepreneurial intention and negatively correlated with introversion. Introversion has a negative correlation with achievement desire, self-efficacy, social network, and entrepreneurial intention, and self-efficacy has a positive correlation with social network and entrepreneurship. Third, social networks have been shown to moderate the relationship between personal characteristics and entrepreneurial intention. Reflecting the results from this study, we expect that those preparing for future start-ups will be a meaningful reference to validate their capabilities and start them.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.1
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• pp.119-133
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• 2024

As a result of significant investments by the government in promoting public technology commercialization and fostering a venture startup ecosystem, there have been quantitative achievements, such as the registration of over 1,600 Innopolis Start-ups since 2006, generating a total revenue of 1.1 trillion won as of 2021. However, these achievements have been overshadowed by critical qualitative challenges, including a continuous decline in average revenue per Innopolis Start-up. This led to a focus on whether managers' technological and market orientations affect business performance. This study aims to provide insights into improving the qualitative growth of Innopolis Start-ups by analyzing the effects of technological and market orientations on business performance, as well as the moderating effects of adjusting marketing and research and development (R&D) costs on this relationship. Through prior research and empirical analysis, this study derives three main findings. First, technological excellence and innovation significantly influence the business performance of Innopolis Start-ups, while technological intensity does not. Second, customer orientation and competitive orientation significantly impact business performance, whereas entry barriers as a single factor do not. Third, adjusting marketing and R&D costs, as controlled variables obtained through general situations, has no direct impact on other variables. However, it interacts with entry barriers, influencing financial business performance, with R&D costs exhibiting a negative buffering effect and marketing costs showing a positive enhancing effect. This study confirms that both technological and market orientations directly influence the business performance of Innopolis Start-ups, thus being crucial factors affecting their growth. Moreover, it establishes that investments in marketing and R&D play significant roles in alleviating initial entry barriers and enhancing financial performance. Consequently, it underscores the importance of reinforcing technological and market orientations tailored to the characteristics of Innopolis Start-ups. Additionally, it proposes five theoretical contributions: strengthening institutional support systems for technology commercialization and innovation, improving qualitative evaluation criteria during the selection process of Innopolis Start-ups, conducting comprehensive analyses of technological and market aspects during startup selection, enhancing support for marketing education and consulting for smooth market entry, and supporting expenditure strategies and milestone setting tailored to the industrial characteristics of individual Innopolis Start-ups.

• Journal of Pharmaceutical Investigation
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• v.24 no.4
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• pp.297-300
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• 1994

Development of hyperlipidemic animal model is prerequisite for the screening of drugs lowering the blood lipoprotein level. In this study, two kinds of diet regimens were tried for the hyperlipidemic effect. The model will be used for the screening of current prescriptions to a variety of diseases related to hyperlipidemia by practioner of traditional herbal medicine. Fifteen male Wister rats of 200g were divided into three groups, and given normal, or either one of the two high cholesterol diets for up to 2 weeks. Regimen HC-1 and regimen HC-2 contained I% and 2% cholesterol in diet, respectively. Total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL) and lower density lipoprotein cholesterol (LDL) levels in the serum were measured before the start of the diet, at 1 week after the start, and at 2 week point. Both regimens resulted in hyperlipidemia with the typical characteristics of increase in TC and LDL, and reduction in HDL, and showed no observable side effects such as diarrhea. In conclusion, both of HC-1 and HC-2 regimens appeared appropriate as diet regimens for the hyperlipidemic rat model.

• Korean Journal of Schizophrenia Research
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• v.22 no.1
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• pp.1-7
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• 2019

Objectives: Clozapine is the drug of choice in treatment-resistant schizophrenia. However, its use is often delayed and a significant proportion of clozapine treated patients fails to respond and experience potentially dangerous side-effects. The aim of this retrospective study was to describe the clinical characteristics of patients started on clozapine and the rate and reason of discontinuation of clozapine. Methods: Medical records of 83 patients started on clozapine during the period of 2012-2016 were reviewed. Results: Clozapine started on patients in chronic phase; the mean age of start was 38.1 years old and the mean number of psychiatric admission was 6.5. A majority (80.7%) of the patients had been subjected to antipsychotic polypharmacy prior to clozapine and most (61.5%) of them were being treated with polypharmacy including clozapine. Overall, 39 (47.0%) subjects had continued clozapine whereas 15 (18.1%) discontinued it; 29 (34.9%) were lost to follow-up. The most common reason for discontinuation was side-effects (n=13) including six life-threatening cases, most of which occurred within 6 months of its start. Conclusion: This study demonstrated that there is some evidence of delays to clozapine use, high rates of polypharmacy and significant rate of discontinuation during the early phase of clozapine treatment.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.2
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• pp.137-151
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• 2020

Since the global financial crisis, the employment rate of young people worldwide has been declining, and the situation in Korea has worsened. Recently, the employment rate has been restored to a small extent due to the implementation of various government policies on youth employment and entrepreneurship, and many young entrepreneurs have been produced. In addition, various types of youth farming enterprises are emerging as the system for encouraging home farmers and villagers and fostering young farmers has been expanded. In this regard, this study examines the influence of CEO's personal characteristics and government's support policies on corporate performance in starting and managing youth rural enterprises. The purpose of this study was to analyze the effect on the performance of rural enterprises. Through this study, it will be able to know what are the important factors for young people to achieve results in starting a rural enterprise. The results of this study suggest three implications. The first is that the personal characteristics of the CEO are important for the performance of youth start-up rural enterprises. Second, in support policy, educational support affects performance, but funding policy does not have a significant effect. Third, since ICT's environmental characteristics do not affect the CEO's personal characteristics and support policies and corporate performance, it is more important to find ways to utilize them directly in the field than to develop ICT's environmental characteristics.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2769-2774
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• 2007

In vacuum ejector-diffuser systems where a finite volume secondary chamber is used, the secondary jet exhibits transient characteristics during start-up. A steady state is achieved after some time in which mass entrainment prevails indefinitely inside the ejector, though there is no flow from the secondary chamber. An attempt is made in this work to study the infinite entrainment of secondary jet into the primary jet from a finite secondary chamber, with the help of a computational fluid dynamics method. The present study is also intended to identify the operating range of vacuum ejector-diffuser systems where the steady flow assumption can be applied without uncertainty. The results obtained show that the only condition in which an infinite mass entrainment is possible is the generation of a re-circulation zone near the primary nozzle exit. The flow in the secondary chamber attains a state of dynamic equilibrium at this point. Steady flow assumption is valid only after this point.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.563-567
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• 2009

The polymer electrolyte membrane fuel cell(PEMFC) with the advantages of low-operating temperature, high current density, low cost and volume, fast start-up ability, and suitability for discontinuous operation becomes the most reasonable and attractive power system for transportation vehicle and micro-grid power plant in a household. 200W PEM-type FCs system was integrated by this study, then the electrical characteristics and diagnosis of the fuel cell were analyzed with variations on mass flow rate and stack temperature. The ranges of the variations are 1~8L/min on $H_2$ volume and $20{\sim}70^{\circ}C$ on stack temperature.