• Journal of the Korea Convergence Society
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• v.8 no.11
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• pp.43-48
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• 2017

Semiconductors are leading the development of industrial technology, leading to miniaturization and weight reduction of electronic products as a leading technology, we are dragging the electronic industry market Especially, the semiconductor manufacturing process is composed of highly accurate and complicated processes, and effective production is required Recently, a vision system combining a computer and a camera is utilized for defect detection In addition, the demand for a system for measuring the shape of a fine pattern processed by a special process is rapidly increasing. In this paper, we propose a vision algorithm using mask image to detect scratch defect of semiconductor pockage. When applied to the manufacturing process of semiconductor packages via the proposed system, it is expected that production management can be facilitated, and efficiency of production will be enhanced by failure judgment of high-speed packages.

• The KSFM Journal of Fluid Machinery
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• v.4 no.3 s.12
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• pp.7-13
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• 2001

The present study investigates convective heat/mass transfer and flow characteristics inside a cooling passage of rotating gas-turbine blades. The rotating duct has staggered ribs with $70^{\circ}$ attack angle, which are attached on leading and trailing surfaces. Naphthalene sublimation technique is employed to determine detailed local heat transfer coefficients using the heat and mass transfer analogy. Additional numerical calculations are conducted to analyze the flow patterns in the cooling passage. The present experiments employ two-surface heating conditions in the rotating duct because the exposed surfaces to hot gas stream are pressure and suction side surfaces in the middle passages of an actual gas-turbine blade. Secondary flows are generated by Coriolis and centrifugal forces in the spanwise and streamwise directions. The ribs attached on the walls disturb the mainflow resulting in recirculation and secondary flows near the ribbed wall. The local heat transfer and flow patterns in the passage are changed significantly according to rib configurations and duct rotation speeds. Therefore, the geometry and arrangement of the ribs are important for the advantageous cooling performance. The experimental results show that the ribs enhance the heat transfer more than $70\%$ from that of the smooth duct. The duct rotation generates the heat transfer discrepancy between the leading and trailing walls due to the secondary flows induced by the Coriolis force. The overal heat transfer pattern on the leading and trailing walls for the first and second passes are depended on the rotating speed, but the local heat transfer trend is affected mainly by the rib arrangements.

• Journal of the Korean Society of Costume
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• v.56 no.3 s.102
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• pp.28-41
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• 2006

The purposes of this study were to analyze 'well-being' lifestyle pursuits depending on consumer types and to classify female consumer types according to their 'well-being' awareness. This study also intended to examine the levels of consumers' participation in pursuing a 'well-being' lifestyle, and to find female consumers' characteristics related to well-being lifestyle. The results of study were as follows: First, female consumers were classified in terms of their lifestyle by using their participation in, and awareness of well-being concerns. The results were divided into four groups: society/family-oriented group, 'well-being' oriented leading group, trend-oriented material wealth pursuit group, and selt~centered/fashionable appearance-oriented group. Second, the results of examining characteristics by female consumer type in terms of their pursuit of a well-being lifestyle show that the 'well-being' oriented leading group had the greatest number of innovators and followers. Also, the trend-oriented material wealth pursuit group consisted of mostly medium level participants, and the self-centered/fashionable appearance-oriented group had the greatest number of 'well-being' lifestyle bystanders. With regards to practical participation group, significant differences were found in the sections of 'health', 'leisure' and 'whole', except for 'appearance management'. With regards to purchase experience of 'well-being' products, the health-oriented leading group was the highest participation level in the sections of 'clothes' and 'food', except for 'residence', in which the society/family-oriented group was the highest. Third, demographical characteristics within female consumer types classified by 'well-being' lifestyle showed that the society/family-oriented group had a high percent of. dedicated housewives in their forties or fifties, and the trend-oriented material wealth pursuit group has a high percent of married people in their twenties or thirties. Also, the self-oriented/fashionable appearance-oriented group had a high percent of unmarried. people in their twenties.

• Journal of Auto-vehicle Safety Association
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• v.9 no.4
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• pp.26-31
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• 2017

The current autonomous vehicle competitions are dominated by a few leading research institutions and universities. Since the leading research groups have been able to accumulate their knowledge and to develop their own algorithms for autonomous vehicle for many years, the technology gap seems too big for other followers to catch up with. On the other hand, recent researches predict that there would be a sharp rise in demand for engineers with background in autonomous vehicle technology. Therefore, it would be warranted to further expand the base of the academia and autonomous vehicle industry. In an effort to achieve this goal, it would be beneficial to hold a new format of autonomous vehicle competition event where undergraduate students can play a leading role. So, this study is to analyze the current autonomous vehicle competitions and thus to establish a strategic plan to develop a unique and improved competition event. This study investigates the pros and cons of the domestic and international autonomous vehicle competitions. Based on the analysis for the current autonomous vehicle competitions, the authors suggest a strategic plan to initiate an autonomous vehicle competition. To implement the aforementioned strategic plan, it is necessary to develop a systematic environment where the education and communication are actively available. Through the strategic plan the authors propose, the newly launching autonomous vehicle competition will able to encourage the undergraduate students and professors to dive in the cutting-edge technology thereby increasing technology competitiveness.

• Journal of Sensor Science and Technology
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• v.29 no.1
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• pp.7-13
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• 2020

Dielectric capacitors are integral components in electronic devices that protect the electric circuit by providing modulated steady voltage. Explosive growth of the electric automobile market has resulted in an increasing demand for dielectric capacitors that can operate at temperatures as high as 400 ℃. To surpass the operation temperature limit of currently available commercial capacitors that operate in temperatures up to 125 ℃, Bi_1/2Na_1/2TiO₃ (BNT), which has a large temperature-insensitive dielectric response with a maximum dielectric permittivity temperature of 300 ℃, was selected. By introducing an intentional A-site cation deficiency and post-heat treatment, we successfully manage to control the dielectric properties of BNT to use it for high-temperature applications. The key feature of this new BNT is remarkable reduction in dielectric loss (0.36 to 0.018) at high temperature (300 ℃). Structural, dielectric, and electrical properties of this newly developed BNT were systematically investigated to understand the underlying mechanism.

• Journal of Sensor Science and Technology
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• v.29 no.1
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• pp.59-62
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• 2020

Currently, increasing attention is being paid to relaxor-based ferroelectric single crystals in photoacoustic images, especially for high-end applications. Among the crystals are (1-x)Pb(Mg_1/3Nb_2/3)O₃-xPbTiO₃ (PMN-100xPT) single crystals located near their morphotropic phase boundary (x = 0.30-0.35) because of their ultrahigh piezoelectric and electromechanical coupling properties. The alternating current poling (ACP) treatment, rather than the conventional direct current poling treatment, has recently been spotlighted due to its effectiveness in enhancing the piezoelectric properties. So far, it has been suggested that the enhanced piezoelectricity originates from either a domain miniaturization to nanodomains or from an electric-field-induced monoclinic symmetry. In this study, we demonstrate by thermally stimulated depolarization current measurements that the effect of ACP is too complex to be explained using a single mechanism and that the proposed electric-field-induced monoclinic symmetry is unlikely to exist.

• The Journal of the Korea Contents Association
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• v.20 no.2
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• pp.1-14
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• 2020

Leading the fourth industrial revolution era requires science and technology strategies that establish original research directions at the national level. To this end, it is necessary to look at the research and development activities for the fourth industrial revolution of technology-leading countries. In this study, the research programs of the U.S. Intelligence Advanced Research Projects Activity(IARPA), an organization focusing on cutting edge research on science and technology information such as artificial intelligence, are investigated by using network analysis. The findings show that, resolving around the information identification and forecasting, decision making and cybersecurity clusters, IARPA's research programs largely focus on finding hidden information and predicting specific events, supporting decision making by considering changes in and outside organizations or establishing cybersecurity. Also, this study finds that China and Japan, representative technology-leading Asian countries, refer to the research programs of IARPA to establish their science and technology policies. The results of this study suggest implications for Korea's science and technology policies in response to the fourth industrial revolution era.

• Journal of Distribution Science
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• v.14 no.10
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• pp.81-91
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• 2016

Purpose - This study proposes a strategic model for the late mover to effectively penetrate an industry that is dominated by a leading company. Thus, this study presents strategic implications for several late movers in overcoming the advantages of the leading company. Research design, data, and methodology - This study begins with a literature review followed by the formation of a strategic model that consists of: Repositioning, Utilization of Competence, Strategic Leadership, and Innovation. Specifically, this research analyzes LG Electronics (LG) as an example and investigates how LG infiltrates and grows in the water purifier market, overcoming the advantages of the powerful leading company. Results - The major steps taken by LG are summarized into four. First, LG studied the market, which had been conventionally treated as a single market. To penetrate the market, LG founded a new, special market segment. Subsequently, LG further segmented the market, executing a marketing strategy for each segment. Second, the unbending will of top managers was a key factor that addressed the challenge persistently. Third, even though LG was the late mover in the water purifier market, it had several technology competences such as compressor, refrigeration cycles, and algorithms. LG had profound knowledge in technology and used it effectively. Fourth, LG created a premium market through three innovative and distinguished factors such as the stainless water tank, sterilization service, and luxury design. Conclusions - This research draws four key findings from the example of the late mover in the water purifier industry: the reestablishment of a strategic position based on environmental change is an effective strategy for the late mover; strategic leadership is an important motive to generate late mover performance; and the late mover can utilize its existing knowledge and resources to overcome the first mover, such as presenting new added value compared to existing products as an effective catch-up strategy. Consequentially, through the study of performance determinants and the market penetration strategy of the late mover, this research has significance in providing basic material for companies trying to penetrate the market.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.12
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• pp.1184-1191
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• 2009

In order to reduce the download around the Smart UAV(SUAV) at Transition mode, flow control using synthetic jet has been performed. Many of the complex tilt rotor flow features are captured including the leading and trailing edge separation, and the large region of separated flow beneath the wing. Based on the results of part 1 of the present work, synthetic jet is located at 0.01c, $0.95c_{flap}$ and it is operated with the non-dimensional frequency of 0.5, 5 to control the leading edge and trailing edge separation. Consequently, download is substantially reduced compared to with no control case at transition mode using leading edge jet only. The present results show that the overall flight performance and stability of the SUAV can be remarkably improved by applying the active flow control strategy based on synthetic jet.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.12
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• pp.1173-1183
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• 2009

In order to reduce the download around the Smart UAV(SUAV) at hovering, flow control using synthetic jet has been performed. Many of the complex tilt rotor flow features are captured including the leading and trailing edge separation, and the large region of separated flow beneath the wing. In order to control the leading edge and trailing edge separation, synthetic jet is located at 0.01c, $0.3c_{flap}$, $0.95c_{flap}$. As non-dimensional frequency, the flow pattern is altered and the rate of drag reduction is changed. The results show that synthetic jets shorten the vortex period and decrease the vortex size by changing local flow structure. By using leading edge jet and trailing edge jet, download is efficiently reduced compared to no control case at hovering mode.