• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.6
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• pp.824-831
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• 2019

For effective development in consideration of the maintainability of the weapon system, it is necessary to understand whether the maintainability design requirements are satisfied at the early phase of development. This requires the application of an early design phase maintainability prediction process to provide opportunities for improvement. By defining the ambiguity group definition, fault isolation level, fault isolation probability, and countermeasures for faults, it was possible to predict early phase development. The MTTR of the initial design phase applying Procedure V to the artillery system was 3.46H, which is about 16 % higher than 2.98H, the MTTR using Procedure II. This is a result of system design ambiguity that has not been specified in the early phase of development.

• IE interfaces
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• v.11 no.1
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• pp.175-182
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• 1998

The maintainability prediction of an underwater military system is considered. A general and parctical prediction method for maintainability using MIL-HDBK-472 is presented. We develop a computer program to predict MTTR of an underwater military system. A case study is made to explain the proposed maintainability prediction method.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.2
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• pp.111-117
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• 2013

In this paper, we have proposed novel technique to improve maintainability for training vehicle of underwater weapon system. In case of under water weapon, the fire procedure is related with operation of expulsion system in submarines. So the submarine crews should practice the complex fire procedure of weapon system by using training vehicle, which is safer and cheaper than operational weapon. After emitted from submarine, the training vehicle rise to the surface and should be withdrawn from the sea. The recovered training vehicle is transported to maintenance depot and pass through the recycling procedure including disassembling the vehicle, data acquisition & analysis, battery charge, replacing expandable components, testing the captive equipment, and assembling the vehicle. The disassembling & assembling of training vehicle which is composed of watertight section or airframe, is time-consuming work. So in this paper, we have studied the elements of recycling procedure and propose the method to exclude the assembling & disassembling work for maintainability improvement.

• Journal of the Korea Society for Simulation
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• v.21 no.4
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• pp.75-80
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• 2012

This paper describes the development and applications of maintainability simulation system based on virtual reality technology. The immersive type maintainability simulator using virtual reality is developed and assembly simulation using DELMIA software is conducted for an air-to-ground munition as an example. The simulation processes and result validate the feasibility and effectiveness of maintainability simulation system for logistic element development.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.191-196
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• 2007

This paper is reviewed RAM(Reliability, Availability and Maintainability) data table utilized for RAM data management to Urban Maglev Transit. As railway systems become more complex, the RAM requirements are reinforced to ensure that a design meets Reliability, Availability, Maintainability criteria. Therefore, it needs the efficient management for RAM data of railway system to meet RAM target. At this study, RAM data management format is suggested to ensure reliability and maintainability based on acquired experience for overseas rolling stock. This RAM data table and FMECA(Failure Mode Effect Criticality Analysis) table are useful to the calculation of MTBF(Mean Time Between Failure), MTBSF(Mean Time Between Service Failure) and Maintainability. Also, this RAM management table will be efficient to improve the RAM evaluation to Urban Maglev Transit.

• Journal of the Korea Safety Management & Science
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• v.10 no.4
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• pp.159-163
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• 2008

This paper proposes various measures of reliability, maintainability and availability in information technology service management(ISTM). Global ITSM standards such as ITIL(IT Infrastructure Library) and ISO/IEC 20000 are introduced. Especially availability management of De-facto and De-juire standards is concerned with users and customers of IT service. The study presents seven reliability measures, six maintainability measures and two availability measures. These results can be effectively used with a appropriate IT availability management tools such as CFIA(Component Failure Impact Analysis) and SOA(Service Outage Analysis), etc.

• Journal of Information Technology and Architecture
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• v.10 no.4
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• pp.537-552
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• 2013

Software-as-a-Service (SaaS) has led to paradigm shifts in the information management area by combining it with SOA and Mashup. System developers now have more chances to access various high-quality functions through API opened on the web. But external resources are controlled by service providers so that it raises the component's uncertainty in system management which is related to external resources. In the cloud environment, components related to external resources causes negative effects on system's maintainability by making them dependant on service providers. This study proposes a way to enhance maintainability by using stable external resources. For this work, we suggest the N+1-tier model in which an external resource tier is added to the N-tier model. After that, we analyze how adding an external resource tier affects the decreasing complexity of maintainability and improving maintainability on web application.

• Journal of the Korean Society for Railway
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• v.11 no.4
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• pp.390-397
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• 2008

Quantitative RAM (Reliability, Availability, Maintainability) is the one of the important indicator that shows the quality of rolling stock. It is usually required in the domestic and abroad purchase specification of rolling stock. And achieving and demonstrating the quantitative RAM goals is also required. In this study, the method to set up these goals will be proposed in the aspects of service and logistic reliability, operational, achievement or inherent availability and maintainability. And we apply this proposed method to the real operation data.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.4
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• pp.119-126
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• 2021

During the development of a weapon system, the concept of maintainability is used for quantitatively predicting and analyzing the maintenance time. However, owing to the complexity of a weapon system, the standard maintenance time predicted during the system's development differs significantly from the measured time during the operation of the equipment after the system's development. According to the analysis presented in this paper, the maintenance time can be predicted by considering the system's complexity on the basis of the military specifications, and the procedure can be Part B of Procedure II and Method B of Procedure V. The maintenance work elements affected by the system complexity were identified by the analytic hierarchy process technique, and the system-complexity-reflecting weights of the maintenance work elements were calculated by the Delphi method, which involves expert surveys. Based on MIL-HDBK-470A and MIL-HDBK-472, it is going to present a Korean-style maintainability prediction method that reflects system complexity of weapons systems.

• Journal of Aerospace System Engineering
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• v.17 no.5
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• pp.1-10
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• 2023

This research sought to determine the optimal cycle of Planned Depot Maintenance (PDM) for Unmanned Aerial Vehicle (UAV), and PDM through Reliability and Maintainability-based simulation and Operating and Support (O&S) cost analysis using Reliability and Maintainability analysis results. The effectiveness of the PDM was verified economically, and the optimal PDM interval that balances UAV effective operations and sustaining engineering costs was presented.