• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.91-97
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• 2004

In this paper, we conducted basic study on the reliability management that is a key factor to develop highly-reliable launch vehicles, and proposed the strategy for reliability management that can be applied to the KSLV program. Based on the analysis of international launch vehicles data, this paper also presented the reliability target that is essential for Korea's entering into the international commercial market.

• Journal of Korean Society for Quality Management
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• v.44 no.1
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• pp.29-42
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• 2016

Purpose: This paper reviews the papers on reliability issues which are published in the Journal of the Korean Society for Quality Management (KSQM) since 1965. The literature review is purposed to survey a variety of reliability issues for several categories Methods: We divide all of reliability issues into 9 categories: acceleration test, reliability estimation, system reliability, software reliability, reliability data collection and analysis method, lifetime distribution, maintenance and warranty strategy, reliability applications, and reliability applications to military area Results: Dividing all of papers on reliability published in KSQM for 50 years into 9 categories, we provide a chronological roadmap for individual categories, and summarize the contents and contributions of surveyed papers Conclusion: The review paper is expected to provide future direction to improve reliaiblity theories and applications in manufacturing and service industries

• Journal of the Korean institute of surface engineering
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• v.36 no.2
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• pp.214-225
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• 2003

Trends in microelectronics packages such as low cost, miniaturization, high performance, and high reliability made area array interconnecting technologies including flip chip, CSP (Chip Scale Package) and BGA (Ball Grid Array) mainstream technologies. Underfill technology is used for the reliability of the area array technologies, thus electronics packaging industry regards it as very important technology In this paper, the underfill technology is reviewed and the recent advances in the underfill technology including new processes and materials are introduced. These includes reworkable underfills, no-flow underfills, molded underfills and wafer - level - applied underfills.

• Journal of Korean Society for Quality Management
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• v.45 no.3
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• pp.365-377
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• 2017

Purpose: In the A rotorcraft, the division of a long yaw control rod was studied to improve the heat treatment capability. The purpose of this study was to analyze whether division of yaw control rod affects quality reliability in the A rotorcraft and analyze whether it secured flight safety. Methods: The structural static test and the vibration durability test on the split shape of yaw control rod were carried out in order to examine and verify the existing structural analysis results. Results: Structural static test results showed that there were no cracks and vibration durability test results showed that there was no damage or breakage on the split yaw control rod. Conclusion: This study showed that the quality reliability was confirmed and thus the flight safety of the A rotorcraft was secured. And it is expected that the split technique of the yaw control rod will contribute to the development of the rotorcraft industry in the future.

• Journal of Welding and Joining
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• v.31 no.3
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• pp.84-88
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• 2013

These days embedded technology may be the most significant development in the electronics industry. The study focused on the development of active device embedding using flexible printed circuit in view of process and materials. The authors fabricated 30um thickness Si chip without any crack, chipping defects with a dicing before grinding process. In order to embed chips into flexible PCB, the chip pads on a chip are connected to bonding pad on flexible PCB using an ACF film. After packaging, all sample were tested by the O/S test and carried out the reliability test. All samples passed environmental reliability test. In the future, this technology will be applied to the wearable electronics and flexible display in the variety of electronics product.

• Journal of Ship and Ocean Technology
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• v.3 no.1
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• pp.27-41
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• 1999

The objective of the paper is to study the impact of changing the traditional hull design of bulk carriers by providing them with a double hull while keeping the same deadweight. It is demonstrated that by introducing the double hull the structural reliability is increased throughout the entire life and also the extend of the needed repair is reduced. The results are obtained with recently developed mathematical tools for the reliability assessment of ship hulls subjected to the existence of multiple cracks both in the stiffeners and in the plating and it models the crack growth process. The effect of corrosion is represented as time dependent. The long-term stress range acting on the elements is defined as a function of the local transverse pressure of the internal cargo and outside sea water combined with the stresses resulting from the longitudinal bending of the hull, which is a combined with the stresses resulting from the longitudinal bending of the hull, which is a combineation of horizontal and vertical bending moments. The effect of maintenance actions is modelled as a stochastic process. The results show that a different design of the midship section improves the structural safety and also the economy with respect to structural repair of bulk carriers.

• Nuclear Engineering and Technology
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• v.53 no.5
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• pp.1658-1663
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• 2021

Research on climate change and global warming on the power generation systems are rapidly increasing because of the Importance of the sustainable energy supply, thus the electricity supply since its growing share, in the end, uses energy supply. However, some researchers conducted this field, but many research gaps are not mentioned and filled in this field's literature since the lack of general statements and the quantitative models and formulation of the issue. In this research, an exergy-based model is implemented to model a set of six power generation technologies (combined cycle, gas turbine, nuclear plant, solar PV, and wind turbine) and use this model to simulate each technology's responses to climate change impacts. Finally, using these responses to define and calculate a formulation for the relationship between the system's energy performance in different environmental situations and a dimensionless index to quantize each power technology's reliability against the climate change impacts called the Pahlev reliability index (P-index) of the power technology. The results have shown that solar and nuclear technologies are the most, and wind turbines are the least reliable power generation technologies.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1422-1431
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• 2015

The reliability of power system components can be affected by a numbers of factors such as the health level of components, external environment and operation environment of power systems. These factors also affect the electrical parameters of power system components for example the thermal capacity of a transmission element. The relationship of component reliability and power system is, therefore, a complex nonlinear function related to the above-mentioned factors. Traditional approaches for reliability assessment of power systems do not take the influence of these factors into account. The assessment results could not, therefore, reflect the short-term trend of the system reliability performance considering the influence of the key factors and provide the system dispatchers with enough information to make decent operational decisions. This paper discusses some of these important operational issues from the perspective of power system reliability. The discussions include operational reliability of power systems, reliability influence models for main performance parameters of components, time-varying reliability models of components, and a reliability assessment algorithm for power system operations considering the time-varying characteristic of various parameters. The significance of these discussions and applications of the proposed techniques are illustrated by case study results using the IEEE-RTS.

• Proceedings of the Korean Reliability Society Conference
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• 2001.06a
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• pp.51-58
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• 2001

No Abstract, See Full Text

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.584-591
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• 2020

Reliability is an important factor in weapons systems. Low reliability causes the weapons system to fail to function properly, which directly leads to the weakening of combat capability. This paper classifies the structure of the 5.56 mm rifle, which is currently used by the Korean army, into a total of seven assemblies and describes the eight functions necessary for the rifle to operate normally. In addition, the concept of reliability was defined as the MRBF, and the Poisson process model and TTT plot were explained as a reliability analysis theory for the repair function system. Next, the field-data obtained by defining failure as the replacement of parts other than periodic exchange of parts were refined, and the reliability was analyzed by entering the refined field operation specifications into the Minitab program. As a result, the reliability of the rifle was determined to be 251.73. The assembly parts that required improvement was identified as the barrel, lower body, and butt stock assembly, and 10 detailed parts needed to be improved. Finally, the limits of the reliability analysis using the field-data currently available for small caliber firearms were considered.