• Journal of Drive and Control
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• v.17 no.4
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• pp.125-132
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• 2020

The objective of this study was to analyze the axle load of a rice transplanter when planting rice seedlings at different working load conditions to select a suitable gear stage and a constant planting depth for rice seedlings. In this study, there are four levels of planting distances (26, 35, 43, and 80 cm) and three planting depths (low, medium, and high) with two gear stages (1.3 and 1.7 m/s). Axle loads and required planting pressures were analyzed statistically. It was observed that axle torques were increased with increasing planting depths for both gear stages, meaning that axle torques were directly proportional to planting depths for both gear stages. It was also observed that required planting pressures had a significant difference between planting distances. Planting pressures also showed significant difference according to gear stage and planting depth. These results indicate that planting pressures were directly proportional to both gear stage and planting depth. Results revealed that the automatic depth control system of a rice transplanter could not guarantee a constant planting depth as supplied pressures were variable. This indicates that a control algorithm is needed to ensure a constant planting depth. In the future, a control algorithm will be developed for an automatic depth control system of a rice transplanter to improve its comprehensive performance and efficiency.

• The Korean Journal of Franchise Management
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• v.11 no.4
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• pp.31-44
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• 2020

Purpose: The purpose of this study is to examine the effects of CEO's self-determination on entrepreneurship, business performance (operational and financial performance). Also, this research provide some strategic insights for improving business performance. In the proposed model, self-determination consists of autonomy, competence, and relatedness, and entrepreneurship consists of innovation, initiative and risk sensitivity, and proactiveness. More specifically, this study proposes a framework that entrepreneurship and operational performance will play mediating roles between self-determination and financial performance. Research design, data, methodology: In this study, an online survey was conducted on SME CEOs for analysis, and a total of 122 samples were used. In the analysis process for hypothesis verification and evaluation, frequency analysis was first performed to identify the demographic characteristics of the respondents, and confirmatory factor analysis was conducted to assess the reliability and validity of the measurement model. In addition, a structural model analysis was conducted to examine the structural relationships between CEO's self-determination, entrepreneurship, and business performance (operational and financial performance) using SmartPLS 3.0. Results: The findings and summary are as follows. First, the autonomy of self-determination has a positive effect on entrepreneurship. Second, the competence of self-determination affects entrepreneurship and operational performance. Third, it affects the innovation, initiative and risk sensitivity of the CEO's entrepreneurship, and ultimately, its operational performance. The results show that the business performance of Start-up also increases when self-determination can be a factor in increasing entrepreneurship in three sub-dimensionalities. Conclusions: The conclusion of this study is that in order for SMEs to develop into a sustainable company by securing competitiveness after start-up, external motivation such as external help and support from the state (local government) is important, but competence and relationship, which are components of self-determination. The intrinsic motivation of the CEO may be more important. To this end, CEO's should prioritize learning for competency development, and the government should pay attention to providing various educational programs through establishment of education policies and education systems to enhance the competency of start-up CEO's.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.579-586
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• 2021

This study examines the application of big data and tasks of tourism based on the case of Jeju Special Self-Governing Province, which used big data for regional tourism policy. Through the use of big data, it is possible to understand rapidly changing tourism trends and trends in the tourism industry in a timely and detailed manner. and also could be used to elaborate existing tourism statistics. In addition, beyond the level of big data analysis to understand tourism phenomena, its scope has expanded to provide a platform for providing real-time customized services. This was made possible by the cooperative governance of industry, government, and academia for data building, analysis, infrastructure, and utilization. As a task, the limitation of budget dependence and institutional problems such as the infrastructure for building personal-level data for personalized services, which are the ultimate goal of smart tourism, and the Personal Information Protection Act remain. In addition, expertise and technical limitations for data analysis and data linkage remain.

• Journal of the Korea Convergence Society
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• v.12 no.2
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• pp.21-28
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• 2021

In this study, we propose a deep learning-based NILM technique using actual measured power data for 5 kinds of home appliances and verify its effectiveness. For about 3 weeks, the active power of the central power measuring device and five kinds of home appliances (refrigerator, induction, TV, washing machine, air cleaner) was individually measured. The preprocessing method of the measured data was introduced, and characteristics of each household appliance were analyzed through spectogram analysis. The characteristics of each household appliance are organized into a learning data set. All the power data measured by the central power measuring device and 5 kinds of home appliances were time-series mapping, and training was performed using a LSTM neural network, which is excellent for time series data prediction. An algorithm that can disaggregate five types of energies using only the power data of the main central power measuring device is proposed.

• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.1
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• pp.1-9
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• 2021

Number of duck and its breeding facilities have been steadily decreasing for financial and social issues in Korea. Therefore, the 'turning point' for duck industry is strongly demanded. In this study, the questionary survey was carried out to provide backgrounds for developing policy and technology for duck breeding farms. The questionary survey aimed to investigate the information of operation strategy of farm, ventilation, cooling and heating. The total number of survey respondents was 74. In case of facility type, 55.4% of respondents stated they used greenhouse type, 31.3% for winch-curtain type, and 2.7% for windowless type (mechanically ventilated facility). More than 85% of the facilities were using 'natural ventilation', it meant that these situation can restrict the not only environmental control but also the supply policy for 'smart farm' of the Government. 44.6% used the combination of the cross-ventilation method and roof-ventilation method for ventilation operation in summer season, and 31.1% followed only the cross-ventilation method. In case of winter season, 36.5% used the cross-ventilation method, and 33.3% used the combination of cross and roof-ventilation, method. For the ventilation strategy, about 86.5% depended on farmer's experience. In case of heating and cooling, 79.7% were using kerosene heater for winter season, and 43.2% were using mist-spray for summer season, respectively. More than 75% stated that cooling and heating strategies were based on farmer's experience. From the analyses of the survey results, a few proposals for developing policy and technology for duck breeding farm was suggested.

• Journal of Digital Convergence
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• v.19 no.3
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• pp.161-166
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• 2021

The macroeconomic concept represents the movement of a country's economy, and it affects the overall economic activities of business, government, and households. In the macroeconomy, by looking at changes in national income, inflation, unemployment, currency, interest rates, and raw materials, it is possible to understand the effects of economic actors' actions and interactions on the prices of products and services. The US Federal Reserve System (FED) is leading the world economy by offering various stimulus measures to overcome the corona economic recession. Although the stock price continued to decline on March 20, 2020 due to the current economic recession caused by the corona, the US S&P 500 index began rebounding after March 23 and to 3,694.62 as of December 15 due to quantitative easing, a powerful stimulus for the FED. Therefore, the FED's economic stimulus measures based on macroeconomic indicators are more influencing, rather than judging the stock price forecast from the corporate financial statements. Therefore, this study was conducted to reduce losses in stock investment and establish sound investment by analyzing the FED's economic stimulus measures and its effect on stock prices.

• Journal of Powder Materials
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• v.28 no.6
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• pp.483-490
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• 2021

A new Fe-Cr-Mo-B-C amorphous alloy is designed, which offers high mechanical strength, corrosion resistance as well as high glass-forming ability and its gas-atomized amorphous powder is deposited on an ASTM A213-T91 steel substrate using the high-velocity oxygen fuel (HVOF) process. The hybrid coating layer, consisting of nanocrystalline and amorphous phases, exhibits strong bonding features with the substrate, without revealing significant pore formation. By the coating process, it is possible to obtain a dense structure in which pores are hardly observed not only inside the coating layer but also at the interface between the coating layer and the substrate. The coating layer exhibits good adhesive strength as well as good wear resistance, making it suitable for coating layers for biomass applications.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.12
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• pp.1904-1913
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• 2021

With the proliferation of smart phones and the development of IoT technology, it has become possible to collect personal data for public purposes. However, users are afraid of voluntarily providing their private data due to privacy issues. To remedy this problem, mainly three techniques have been studied: data disturbance, traditional encryption, and homomorphic encryption. In this work, we perform simulations to compare them in terms of accuracy, message length, and computation delay. Experiment results show that the data disturbance method is fast and inaccurate while the traditional encryption method is accurate and slow. Similar to traditional encryption algorithms, the homomorphic encryption algorithm is relatively effective in privacy preserving because it allows computing encrypted data without decryption, but it requires high computation costs as well. However, its main cost, arithmetic operations, can be processed in parallel. Also, data analysis using the homomorphic encryption needs to do decryption only once at any number of data.

• Journal of the Korea Society of Computer and Information
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• v.27 no.4
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• pp.61-77
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• 2022

The purpose of this study is to explain intention to use untact medical diagnosis and consultation services. We carried out the analysis of the survey data using Smart PLS 3.0 to test the hypotheses how the expected benefit variables and perceived risk variables of untact medical diagnosis and consultation services affect intention to use. According to the empirical analysis results, this study confirmed that quality of telemedicine service had a significant effects on perceived usefulness, Perceived Easy of Use. And accessibility had a significant effects on perceived easy of use, cost saving and expected benefits had a significant effects on use Intention of untact medical diagnosis and consultation services. Performance risk and service risk had a significant effect on medical risk. And medical risk had a significant negative(-) effects on use Intention of untact medical diagnosis and consultation services. This study has its meaning because it found out that it deals structurally and expansively with use intention of untact medical diagnosis and consultation services through positive and negative factors.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.3
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• pp.281-291
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• 2022

Global warming is accelerating due to the use of fossil fuels that have been used continuously for centuries. Now, humankind recognizes its seriousness, and is conducting research on searching for eco-friendly and sustainable energy. In the field of solar energy, which is a kind of eco-friendly and sustainable, many studies are being conducted to enhance the output performance of the module. In this study, the output improvement for the shingled module structure was studied. In order to improve the output performance of the module, the thickness of the encapsulant was increased, and the lamination process conditions have been improved accordingly. After that, the crosslinking rate was analyzed, and the suitability of the lamination process conditions was judged using this. In addition, a peeling test was conducted to analyze the correlation between the adhesion of the encapsulant and the output performance of the module. Finally, the optimization for the encapsulant material and the lamination process conditions for high-power shingled modules was established, and accordingly, the market share of high-power shingled modules in the solar module market can be expected to rise.