• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.11
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• pp.1600-1604
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• 2017

Mo-Cu alloys have been widely used for heat sink materials, vacuum technology, automobile and many other applications due to their excellent physical and electronic properties. Especially, Mo-Cu composites with 5~20 wt% copper are widely used for the heavy duty service contacts due to their excellent properties like low coefficient of thermal expansion, wear resistance, high temperature strength and prominent electrical and thermal conductivity. In most of the applications, high dense Mo-Cu materials with homogeneous microstructure are required for high performance, which has led in turn to attempts to prepare ultra-fine and well-dispersed Mo-Cu powders in different ways, such as spray drying and reduction process, electroless plating technique, mechanical alloying process and gelatification-reduction process. However, most of these methods were accomplished at high temperature (typically degree), resulting in undesirable growth of large Cu phases; furthermore, these methods usually require complicated experimental facilities and procedure. In this study, Mo-Cu alloying were prepared by planetary ball milling (PBM) and spark plasma sintering (SPS) and the effect of Cu with contents of 5~20 wt% on the microstructure and properties of Mo-Cu alloy has been investigated.

• Journal of Information Technology Services
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• v.11 no.4
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• pp.295-308
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• 2012

Software and Systems Product Line(SSPL) is a paradigm that has been developed and applied by European Union(EU) to achieve the productivity and competitiveness of EU industries on the world market. It is not just a simple system or software development methodology, but a sophisticated technology requiring capabilities for a high level of mass customization, platforms, processes and convergence of software and systems. EU has applied SSPL for the five selected industrial sectors including aerospace, automobile, medical equipment, consumer electronics and telecommunication equipment since 1990s and led the way to other industry sectors to stimulate the application of SSPL from 2006. In order for Korea to secure competitiveness in the manufacturing and service industries in the competitive borderless market, it is essential to gain the high level of capabilities for software development and convergence of software and systems. SSPL can be a powerful means to achieve this end. This paper discusses the paradigmatic concept of SSPL, how EU's major industries and companies have secured competitiveness through SSPL, key capabilities that are necessary for successful institutionalization of SSPL in Korea, and finally suggestions on core strategies to materialize the benefits of SSPL for Korea.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.3
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• pp.193-198
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• 2017

This paper discusses the design and control of a switched reluctance motor (SRM) drive system for a built-in car vacuum cleaner. The growing popularity of outdoor activities and recreation has led the automobile industry to expand technologies that increase the convenience of vehicles, and thus, a built-in car vacuum cleaner was introduced. However, the existing DC motor of a vacuum cleaning system has several disadvantages, such as maintenance cost and lifespan issues of its commutator-brush structure. An SRM can be a good alternative to the existing DC motor because of its high-speed capability, long lifespan, low maintenance cost, and high efficiency, among other advantages. A prototype SRM drive is designed and manufactured to verify its feasibility for use in a built-in car vacuum cleaning system. Dynamic simulation is conducted to determine the optimal switching angle for maximum efficiency and minimum torque ripple. Load test, noise measurement, and suction-power tests are also carried out.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.2
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• pp.45-50
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• 2021

In the recent fourth industrial revolution, the demand for additive processes has emerged rapidly in many mechanical industries, including the aircraft and automobile industries. Additive processes, in contrast to subtractive processes, can be used to produce complex-shaped products, such as three-dimensional cooling systems and aircraft parts that are difficult to produce using conventional production technologies. However, the limitations of additive processes include nonuniform surface quality, which necessitates the use of post-processing techniques such as subtractive methods and grinding. This has led to the need for hybrid machines that combine additive and subtractive processes. A hybrid machine uses additional additive and subtractive modules, so product deformation, for instance, deflection, is likely to occur. Therefore, structural analysis and design optimization of hybrid machines are essential because these defects cause multiple problems, such as reduced workpiece precision during processing. In this study, structural analysis was conducted before the development of an additive/subtractive hybrid processing machine. In addition, structural optimization was performed to improve the stability of the hybrid machine.

• Journal of Korea Society of Digital Industry and Information Management
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• v.18 no.4
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• pp.77-83
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• 2022

As users' needs for customized services increase, the service provision method is changing from a vertical structural service provision method to a horizontal structural service provision method. This paradigm shift has led to a change from the way existing users find the content they want to find and provide customized needs of users by content providers. With the recent development of smartphones and various AI technologies, demand for providing seamless services such as smartphones is increasing in automobiles. However, it is difficult to provide services in line with changes in this service paradigm because automobile services provide services centered on finished car manufacturers rather than individually providing services tailored to user needs. In this paper, we develop a Node-RED-based dynamic vehicle service simulation tool so that users can use the service they want in cars. The simulation tool developed provides a simulation environment for services authored by the user using NodeRed by writing, registering, and using NodeRed.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.55-60
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• 2022

Acceleration of the pace of life, increasing the amount of information, the emergence of "clip way of thinking" as a phenomenon has led to the problem of choosing forms of presentation of educational materials to students. One of the ways to solve this problem is to use the means of visualization of information flow, forasmuch as the thinking of modern youth is more effective in perceiving visual images than verbal means. The purpose of the research is to prove the effectiveness of the use of visualization in the process of teaching Ukrainian as a foreign language to students with clip way of thinking. The following methods have been used, namely: analysis, synthesis, comparison, systematization and generalization of scientific literature; testing and surveys; pedagogical experiment; quantitative and qualitative analysis of data, interpretation and generalization of the research results. The essence of visualization means has been revealed; the expediency of their use in the methodology of teaching foreign students the Ukrainian language has been substantiated. It has been proven that the role of Ukrainian teachers lies in taking into account all new trends in teaching, integrating computer perception of information by foreign students into teaching technology and using cognitive visualization in order to intensify the learning process.

• Design & Manufacturing
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• v.14 no.1
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• pp.8-14
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• 2020

In general, auto parts production assembly line is assembled and produced by automatic mounting by an automated robot. In such a production site, quality problems such as misalignment of parts (doors, trunks, roofs, etc.) to be assembled with the vehicle body or collision between assembly robots and components are often caused. In order to solve such a problem, the quality of parts is manually inspected by using mechanical jig devices outside the automated production line. Automotive inspection technology is the most commonly used field of vision, which includes surface inspection such as mounting hole spacing and defect detection, body panel dents and bends. It is used for guiding, providing location information to the robot controller to adjust the robot's path to improve process productivity and manufacturing flexibility. The most difficult weighing and measuring technology is to calibrate the surface analysis and position and characteristics between parts by storing images of the part to be measured that enters the camera's field of view mounted on the side or top of the part. The problem of the machine vision device applied to the automobile production line is that the lighting conditions inside the factory are severely changed due to various weather changes such as morning-evening, rainy days and sunny days through the exterior window of the assembly production plant. In addition, since the material of the vehicle body parts is a steel sheet, the reflection of light is very severe, which causes a problem in that the quality of the captured image is greatly changed even with a small light change. In this study, the distance between the car body and the door part and the door are acquired by the measuring device combining the laser slit light source and the LED pattern light source. The result is transferred to the joint robot for assembling parts at the optimum position between parts, and the assembly is done at the optimal position by changing the angle and step.

• KDI Journal of Economic Policy
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• v.26 no.2
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• pp.249-280
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• 2004

This paper analyzes the industrial growth of Korea in the 1990s and its relationship with the nation's export performance. The result shows that total factor productivity (TFP) played a significant role in the growth of some industries, where in particular a sharp increase in TFP was observed in the electrics and electronics industry and the automobile industry in the late 1990s. While CEPII RCA indexes for the Korean industries such as IT industry and automobile industry significantly increased since 1998, only limited evidence was found that TFP or TFI influenced RCA. Investigating Korea's export performance in the Northeast Asian context, this paper shows that, in the 1990s, the growth of Korea's exports to Japan was led by industries that recorded relatively fast growth in total factor input (TFI). In contrast, that to China was almost equally contributed by industries that experienced relatively fast growth in TFP or TFI. This paper also investigates competition between Korea and China, and Korea and Japan in the world market. The competition between Korea and China was relatively stronger for the Korean industries to whose growth TFI made a more significant contribution. While no decisive evidence is found for the relationship between TFP growth in Korean industries and their competition against Japan in the world market, it is revealed that the competition between Korea and Japan became less intense for the Korean industries to whose growth TFI made a stronger contribution. In this regard, the paper supports the view of 'nut-cracking' that the Korean economy has lost its competitiveness in the sectors where it maintained comparative advantage, but failed to catch up more advanced countries such as Japan by gaining competitiveness in more capital or technology intensive sectors.

• Korean Journal of Labor Studies
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• v.24 no.1
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• pp.65-105
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• 2018

This study examines the employment relations of TNC subsidiaries in Central and Eastern Europe(CEE). Specifically, this study analyzes the employment relations of Volkswagen subsidiaries, which has led the restructuring the CEE's automobile industry since the collapse of socialist regimes, and Hyundai subsidiaries, which has sought to cast employment relations through Greenfield Investment as a latecomer. After the collapse of socialism, with the massive inflow of foreign direct investment and the social legacy of weak labor unions, CEE has been included in the global production network as low-wage production base. Both VW and Hyundai have entered the CEE with their own characteristics and global strategies that have been developed in their home countries and have developed the local production. In the process, both have formed local employment relations, combining low-wage, unstable employment, and weak labor unions of CEE under their own strategy. In recent years, however, it has been doubtful of the sustainability of employment relations based on the advantages of low-wage production bases, as the pools of low-wage workforce decline and new union movements occur in CEE. These changes in CEE are an indication of the inherent contradiction of low-wage production base strategies.

• Science of Emotion and Sensibility
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• v.13 no.2
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• pp.309-316
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• 2010

This paper proposes healthcare bathing system for improving the multisensory function and not washing. We designed various types of bathtub for developing bathing system. This system consists of whirlpool bathtub for multisensory stimulation, a cover of bathtub with visual-auditory stimulation function, a small size PC for main control, touch panel, digital multimedia broadcasting (DMB), color-changeable LED mood lighting system for improving visual sensibility and speaker. We investigate the effects on autonomic nervous system during bathing with healthcare bathing system for improving the multisensory functions. To analysis physiological parameter, body temperature, blood pressure, intraocular pressure and heart rate variability (HRV) were measured before, during and after bath using healthcare bathing system. Experiments were performed on partial immersion bath and the water temperature was kept $39{\pm}0.5^{\circ}C$. The body temperature and the heart rate variability of the subject were measured every 5 minutes before, during, and after the bath. In analysis of HRV, the parasympathetic nerve increased from starting bath and decreased after 15 minutes. So the subjects felt comfortable at 15 minutes after starting bath. Blood pressure decreased to 16mmHg maximumly however pulse increased. Bath using healthcare bathing system for improving the multisensory functions affects positively the circulation of the blood. From this results, it leaves something to be desired in evaluation of serviceability and physiological analysis using the healthcare bathing system, however, we expect to analyze more clearly the relationship between the serviceability of product, physiological change and sensibility by various physiological parameters.