• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.397-400
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• 2004

The direct extrusion with porthole die can produce condenser tube which has the competitive power in costs and qualities compared with the existing conform extrusion. In general, porthole die extrusion has a great advantage in the forming that produces the hollow sections difficult to produce by conventional extrusion with a mandrel on the stem. Especially, condenser tube manufactured by porthole die belongs to sophisticated part and demands tighter dimension tolerance and higher surface finish than any other part. In order to confirm the general of porthole die extrusion, we perform the 3D FE analysis of hot porthole extrusion in non-steady state by using DEFORM 3D and investigate a pattern of elastic deformation for porthole die through the stress analysis using ANSYS 5.5 during extrusion process.

• Journal of Information Processing Systems
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• v.3 no.2
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• pp.64-72
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• 2007

Mobile technology appears promising as a method to promote group performance in circumstances dependent on time, but not member proximity. However, the success of mobile technology in group decision-making situations has not yet been proven. This paper aims to see how mobile technology affects the performance of group decision-making tasks that should be resolved urgently and/or sources of idea are disconnected with on-line network. Laboratory experiment was used to investigate the effects of mobile factors on group decision-making. The results from the experiment supported the proposition that pressures of time and location play a significant role in the assessment of group decision performance measures. We found that the adoption of mobile technology to group decision-making procedures might be competitive when group decision-making tasks are urgent and sources of idea are disconnected with on-line network, even though mobile technology is not a panacea on which to depend when designing group decision-making.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.2
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• pp.1-4
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• 2015

Qualification includes all activities to demonstrate that a product meets and exceeds the reliability goals. Manufacturers need to spend time and resources for the qualification processes under the pressure of reducing time to market, as well as offering a competitive price. Failure to qualify a product could result in economic loss such as warranty and recall claims and the manufacturer could lose the reputation in the market. In order to provide valid and reliable qualification results, manufacturers are required to make extra effort based on the operational and environmental characteristics of the product. This paper discusses optimal interval censoring design for reliability prediction of electronic packages under limited time and resources. This design should provide more accurate assessment of package capability and thus deliver better reliability prediction.

• Progress in Superconductivity and Cryogenics
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• v.17 no.3
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• pp.41-46
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• 2015

Recently, the development of the HTS power cable is actively promoted. As the length of HTS power cable increases, there have been many efforts to develop large capacity cryocooler. Among the various cryocooler, the Brayton refrigerator is the most competitive for HTS power cable. The Brayton refrigerator is composed of recuperative heat exchangers, a compressor, and a cryogenic turbo expander. In these components, the cryogenic turbo expander is a part to decrease the temperature and it is the most significant component that is closely related with overall system efficiency. It rotates with high speed using a high-pressure helium or neon gas at cryogenic temperature. This paper describes the design of a 10 kW class Brayton refrigeration cycle and the cryogenic turbo expander. Flow and structural analysis are performed for the rotating impeller and nozzle to verify the efficiency and the design performance.

• Asia pacific journal of information systems
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• v.3 no.2
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• pp.145-168
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• 1993

It has been asserted that information technology (IT) is being exploited by a number of corporations for strategic advantage. The successful implementation of an organization-wide IT, however, not only depends on its strategic and technological feasibility, but also on the effectiveness of organizational transformation strategies. In this case, the organizational transformation strategy and its success for the adoption of computerized typesetting systems (CTS) by one of the largest Korean newspaper companies, are described With an analysis on the Korean newspaper industry, the case explains the internal and external pressure towards the introduction of the new information technology and its development process. It also provides the architecture and operational mechanism of the CTS. Finally, the case analyzes the impact of the system on the competitive behaviors of the rivals in the industry.

• Proceedings of the KIEE Conference
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• 2004.11d
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• pp.63-66
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• 2004

It is widely known that the ultra high frequency (UHF) method that detects the electromagnetic wave of the PD pulses in the gas insulated space is one of the most competitive methods for its high sensitivity. From the above point of view, this paper describes the characteristics of GIS PD signals measured with ultra wide band (UWB) GIS PD defecting system in which PD signals are defected into the dual UHF band. Thc UWB PD detection system consists of the UWB UHF coupler, the UWB low noise amplifier (LNA) and the oscilloscope. The dual bands for PD signals are 0.5-2GHz(full band) and 1-2GHz(high band). As results, it was found that the partial discharges of each defect have their own characteristic pattern and the ratio of High hand to Full band increases with gas pressure.

• Journal of Information Technology Services
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• v.13 no.3
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• pp.1-23
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• 2014

This study investigates the effect of technological and environmental factors on the cloud computing assimilation, which then affects firms' performance. The technological characteristics include cost-savings, technology use advantage, technology infrastructure, and technology compatibility while environmental characteristics include partner cooperation, competitive pressure, environmental uncertainty, and business agility. Furthermore, we examine inter-organizational trust as a moderating effect between environmental characteristics and cloud computing assimilation. Data from a sample of 219 firms show the significant impacts of proposed variables with exception of technology infrastructure and technology compatibility. The findings also show that inter-organizational trust has a significant moderating effect in all paths except the one between business agility and cloud computing assimilation. The implication of this study suggests a theoretical framework explaining cloud computing assimilation and performance within inter-organizational environment.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1441-1446
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• 2008

Seoul Metro Line 9 (SML9) is the first subway line that private capital invests in Korea. SML9 will cross Seoul, linking the Gimpo Airport to the Gangnam district (25.5km) opening in the first half of 2009. SML9 has a new model in Korea constructed by metropolitan government and private company and operated by specialized public transportation service provider. SML9 is confronted with tough environment of stagnated public transportation and strong competitor, Olympic city expressway. And SML9 is under pressure for showing high efficiency as non-governmental organization from both customers and government. Consequently SML9 must lead the maximum efficiency by using its material and human resource. It is necessary that SML9 raise a competitive power and display its ability in active collaboration with relative organization and company. Hereupon, I propose renovation plans from viewpoint of operation field of SML9, (1) efficient train scheduling regime focusing on the combination of express and local train (2) close connection of other mean of transportation and (3) effective connection convention with Airport Railroad (AREX) as the line connected directly.

• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.2
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• pp.13-30
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• 2010

Existing domestic ink market had some problem because of dependence on CPP import, increasing cost, competitive price. For this reason, previous speed of research and developments are very slow. Therefore, develop the new waterborne type of non-chlorine resin, enhance the nation's position with manufacturing outstanding products. Through this thesis, the purpose is mix the polar resin and non-chlorine resin with many proportion and manufacturing better product than existing resin. Pilot production samples have run the test of adhesion, transparency, water resist and resist high pressure car washing. In conclusion, this thesis found that mix acryl Urethane resin and Non-Chlorine resin is the optimum condition.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.5
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• pp.670-678
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• 1999

Heat recovery steam generator(HRSG) is a principal component of the combined cycle power plant (CCPP) which utilizes the waste energy of the gas turbine exhaust gas. A design of the HRSG is a keypoint to achieve high cycle efficiency with competitive cost. This paper presents a brief review on the design of a HRSG which covers the basic design parameters and their effects on the performance and the investment cost. Finally the concept of the optimum design point is presented according to the selection of a pinch point temperature difference and a steam pressure as an illustrated case.