• Journal of Aerospace System Engineering
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• v.16 no.2
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• pp.1-12
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• 2022

The purpose of this study was to investigate the supply and demand structure of the domestic space industry through analysis of industrial concentration index, by sector and dependence on revenue by customer type. As a result of industrial concentration analysis, in the case of space application, a supply monopoly or oligopoly structure was revealed in fields such as satellite broadcasting, space insurance, and satellite navigation. In the field of space equipment manufacturing, referred to as the traditional space industry, a supply monopoly structure appeared only in the field of launch pads and test facilities. As a result of analyzing the dependence on revenue by customer type, the dependence on the demand in the space application field is diversified among foreign countries, private institutions, and others. However, in the case of space equipment manufacturing, it is highly dependent on the demand of public institutions, and it seems that there is a monopsony structure.

• Journal of Information Technology Applications and Management
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• v.26 no.6
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• pp.65-78
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• 2019

This study describes the accounting approach of separating the value chain components that occur between the origin and destination of a country's total exports, and applied this analysis to the nation's information and communication industry. As a result of this study, the analysis results of ICT's global value chain for the United States and China, focusing on Korea, are as follows: First of all, the value added standard was relatively lower than the export amount standard for the information and communication industry. In particular, the gap was starkly visible in the information and communication manufacturing sector, where global vertical specialization was developed relatively. As a representative sector, the computer-related equipment sector exported to China became more specialized vertically than other information and communication industries. Next, the method of participating in vertical specialization of Korea's information and communication sector and its relative position in the global value chain came from domestic products (0.25/35.16) whose total exports, which were double calculated in the case of the U.S. market, returned home. On the other hand, about 32.68 percent returned to the Chinese market. Finally, in the global value chain level, the SW sector occupied a medium vertical culture location for the information and communication equipment sector and the information and communication service sector.

• Journal of the Korean Society of Safety
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• v.37 no.4
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• pp.120-128
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• 2022

Printed circuit boards (PCBs) are a basic component in the electronics industry and are widely used in nearly all electronic products, such as mobile phones, tablet computers, and digital cameras, as well as in electric equipment. PCB manufacturing involves the use of many chemicals and chemical processes and therefore has more risks than other manufacturing sectors. This study aims to identify the causes of possible accidents during PCB manufacturing through risk assessment, develop and implement safety measures, and evaluate the effectiveness of these measures. Note that the safety measures developed to mitigate the risks of a certain process were also implemented for other similar processes. The risk assessments conducted over seven years, from 2015 to 2021, at a PCB manufacturing company identified 361 hazardous processes. Between 2016 and 2019, 41-56 hazardous processes were identified per year; such processes decreased to fewer than 20 per year after 2020. Application of the risk assessment results to the improvement of the hazardous processes with the similar characteristics seems to be effective in decreasing the risks. Equipment-related factors such as lack of appropriate maintenance, low work standards, and defective protection devices were responsible for 59.8% of all possible accidents. Because PCB manufacturing involves many chemicals, skin contact with hazardous substances, electric shock, fire, and explosion were the most common types of possible accidents (81.7%). In total, 505 safety measures were implemented, including 157 related to purchase and improvement of equipment and devices for safety (31.1%), 147 related to the installation/modification of fire prevention facilities (29.1%), and 69 related to the use of standard electrical appliances (13.7%). Risk assessment conducted after implementing the safety measures showed that these measures significantly decreased risk; 247 processes (68.4%) had a risk level of 3, corresponding to "very low," and 114 processes (31.6%) showed a risk level of 4, corresponding to "low." In particular, risk assessment of 104 processes with risk scores of 12 and 10 other processes with risk score of 16 showed that the risk decreased to 4 after implementing the safety measures. Thus, implementing these measures in similar manufacturing sectors that involve chemical processes can mitigate risk.

• Journal of the Korean Society of Systems Engineering
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• v.11 no.2
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• pp.41-49
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• 2015

Industrial safety is one of the crucial agenda for Government as well as Manufacturing Industry. To cope with the needs, a great deal of policies and technical implementation have been proposed and implemented. With a great increasing attention on the Industry 4.0 and Smart Factory, industrial safety has received as a crucial agenda by the manufacturing industry in particular. Up until now, almost all of them have been made from the environmental aspects, rather than operator or workers. In this paper, we present our research results how to increase the workers' safety via smart factory technology, such as IoT and CPS. Our approach has been to see the problem from SE perspectives, to draw the real issues from the various stakeholders, and define how to solve the problem based on the emerging technologies. The developed systems can give conceptual framework for the 'smart' industrial safety system by providing solution architecture for how to monitor the location of workers, and moving equipments, and generate solutions how to avoid safety problems between them if detected.

• Journal of Practical Engineering Education
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• v.9 no.1
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• pp.49-56
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• 2017

Recently, due to Industry 4.0, there is a great interest in smart factory for productivity improvement and customer satisfaction in manufacturing industry, and construction is also actively pursued by government support. In particular, data integration and fieldbus communication technology to build an efficient production system are essential. Fieldbus is an open control system that is not tied to a specific vendor system and has various advantages such as compatibility with other products, accuracy of data transmission, and remote diagnosis. However, there are no educational equipment for training field buses, training courses and examples for practical training, and there are many limitations in improving the practical skills needed for building smart factories in the industrial field. Therefore, this study develops PLC based fieldbus education equipment and training course based on previous research results that selected PLC and communication technology suitable for domestic industry field for practical fieldbus training and develops the training program of Ethernet IP, Profibus DP, Modbus, CC-Link, and DeviceNet. In addition, it is confirmed that the control and remote diagnosis of distributed field devices are possible by data collection and monitoring.

• The Journal of Korean Institute for Practical Engineering Education
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• v.3 no.2
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• pp.136-141
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• 2011

The current tendency on development and change of equipment system in the factory are overlapped with the specific field of the existing systems such as PLC, DCS and SCADA, and the limited portion of the systems in the specific field stands in their own field. Specially, systematic integration, inspection control system and manufacturing management system, management information system are getting closely linked and therefore we increasingly need the open system. Meeting the needs, manufacturing automated equipments in the factory overcoming the shortcomings of unlinked unit equipment recently are getting changed to the phase closely linking with other systems. The training systems for the university, however, have not kept up with the needs from the industry, in spite that fused complex function and performance are asked in the field. To solve the problems, we suggest that the training courses and the equipment designed for the undergraduate education.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.2
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• pp.51-56
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• 2016

High brittleness is a characteristic of glass, and in many cases it is broken during the process of machining due to processing problems, such as scratches, chipping, and notches. Machining defects occur due to the vibration of the equipment. Therefore, design techniques are needed that can control the vibration generated in the equipment to increase the strength of tempered glass. The natural frequency of the machine tool via vibration analysis (computer simulation) must be accurately understood to improve the design to ensure the stability of the machine. To accurately understand the natural frequency, 3D modeling, which is the same as actual apparatus, was used and a constraint condition was also applied that was the same as that of the actual apparatus. The maximum speeds of ultrasonic and high frequency, which are 15,000 rpm and 60,000 rpm, respectively, are considerably faster than those of typical machine tools. Therefore, an improved design is needed so that the natural frequency is formed at a lower region and the natural frequency does not increase through general design reinforcement. By restructuring the top frame of the glass processing, the natural frequency was not formed in the operating speed area with the improved design. The lower-order natural frequency is dominant for the effects that the natural frequency has on the vibration. Therefore, the design improvement in which the lower-order natural frequency is not formed in the operating speed area is an optimum design improvement. It is possible to effectively control the vibrations by avoiding resonance with simple design improvements.

• Korean Management Science Review
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• v.12 no.2
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• pp.1-14
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• 1995

Recently Korean textile industry has been in the phase that requires its strategy change from the less-develped country style of the labor-intensive products to the developed country style of the technology-intensive products. It needs to make more efforts to develop the value-added products to meet the customer's various needs. In addition, development of technology, equipment, and design is required to implement its corporate strategy successfully. Although Korean textile companies have currently kept skillful labor and advanced equipments, they are losing their share in the international textile markets. This is mainly because corporate management has not been involved with efficient strategy. Strategy is an adoption of a company to environment by its corporate members, thus leading to the requirement of coordination of the main functions such as manufacturing and marketing. In fact, the coordination of the two departments toward reaching the corporate goal is not easy since the two are interested in different areas, respectively. Manufacturing people show their interests in production capacity, equipment layout, process technology, quality, purchasing, and labor while marketing people, target customer, product mix, advertisement, product specification, and customer service. For this reason, conflicts sometimes happen between the two departments. There are, however, many area that need a horizontal cooperation, for instance, in layout, process technology, product mix, and potential demand. Therefore, reciprocal coordination is necessary for achieving the firm's common objectives. This study was concerned with determining the factors that enhance the competitiveness of textile firms so that they could reach the common goal of the two departments with a horizontal collaboration.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.4 no.3
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• pp.13-19
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• 2005

Metal Bearing's research that use the clad steel had led in advanced country. Metal Bearing that is produced by domestic companies is ship, vehicles, development equipment and plant equipment. This is Cast White Metal Lining Bearing that is Bimetal Bearing standing 2 generation. Cast White Metal Lining Bearing is foreseen to be used widely on industry whole in the future. Cast White Metal Bearing is product that need precision processing. But the technique is generalized widely. So an advanced country is depending on import from a developing country that price is cheaper than itself manufacture. it is judged that high added value creation by deepening of price competition is difficult. Therefore need product development of new form and is changing to Trimetal Bearing parts. Trimetal Bearing is high quality technique that do compression junction to thin plates of special object on the Back Metal. Therefore, this research developed Trimetal bearing's materials.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.9
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• pp.64-71
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• 2019

We herein propose a systematic design method of hydraulic pipes used in heavy construction equipment. We found that even though many design studies have been conducted regarding major hydraulic components such as pumps, cylinders, and control valves, studies regarding the optimal design of hydraulic pipes are scarce. In this study, the design of four types of pipes is considered: two high-pressure and two low-pressure pipes. First, fluid flow analysis was conducted based on oil flow and pressure for various radii of curvature. For a check-valve pipe, we considered the location of an inlet pipe. We could visualize fluid flow inside the pipe according to the flow velocity and pressure distribution. Based on fluid flow analysis, we conducted a structural analysis that revealed the stress distribution and concentration for each pipe design. We selected the best design parameters for each pipe design, fabricated the pipes, and subsequently tested them for validity.