• 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 Korean Society of Industrial and Systems Engineering
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• v.43 no.3
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• pp.41-52
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• 2020

This paper investigates the stress-reducing preventive maintenance model through numerical experiments. The preventive maintenance model is used to analyze the relationship between related conditions and variables to gain insight into the efficient operation of the system when performing preventive maintenance in real-world situations. Various preventive maintenance models have been developed over the past decades and their complexity has increased in recent years. Increasing complexity is essential to reflect reality, but recent models can only be interpreted through numerical experiments. The stress-reducing preventive maintenance is a newly introduced preventive maintenance concept and can only be interpreted numerically due to its complexity, and has received little attention because the concept is unfamiliar. Therefore, for information purposes, this paper investigates the characteristics of the stress-reducing preventive maintenance and the relationship between parameters and variables through numerical experiments. In particular, this paper is focusing on the economic feasibility of stress-reducing preventive maintenance by observing changes in the optimal preventive maintenance period in response to changes in environmental stress and the improvement factor. As a result, when either the environmental stress or the improve effect of stress-reducing preventive maintenance is low, it is not necessary to carry out the stress-reducing preventive maintenance at excessive cost. In addition, it was found that the age reduction model is more economical than the failure rate reduction model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.247-254
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• 2019

Recently, in designing military equipment, considerable attention has been paid to maintaining operations, including reliability, maintenance, and maintenance time of equipment, from the early stages of development. Therefore, both users and developers stress the importance of design considering the maintenance time. This study evaluated the specific methodologies for predicting the realistic maintenance time, such as the access complexity of equipment, other than the standard maintenance time provided by the conventional method mil-hdbk-470a at the beginning of the design, and applied the time conversion factor using a measure of the maintenance complexity. In addition, the actual maintenance time reflecting the actual maintenance time of the developed equipment and the time-conversion factor applied was compared/verified to confirm the reliability of the data. In a study to set a target for repair and the repair of equipment design in the future, it is expected that the maintenance time of equipment that fails to measure the maintenance time for the initial actual equipment will be reflected as a more realistic time. Moreover, activities, such as research and design reflection activities, will be performed to reduce the maintenance time, operational maintenance cost, etc.

• Journal of information and communication convergence engineering
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• v.4 no.1
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• pp.23-27
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• 2006

The discipline of software performance is very broad; it influences all aspects of the software development lifecycle, including architecture, design, deployment, integration, management, evolution and servicing. Thus, the complexity of software is an important aspect of development and maintenance activities. Much research has been dedicated to defining different software measures that capture what software complexity is. In most cases, the description of complexity is given to humans in forms of numbers. These quantitative measures reflect human-seen complexity with different levels of success. Software complexity growth has been recognized to be beyond human control. In this paper, we have focused our discussion on the increasing software complexity and the issue with the problems being faced in managing this complexity. This increasing complexity in turn affects the software productivity, which is declining with increase in its complexity.

• IE interfaces
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• v.14 no.3
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• pp.272-285
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• 2001

Proper maintenance techniques have been emphasized in recent years due to increased safety and reliability requirements of systems, increased complexity, and rising costs of material and labor. In the related literature, most studies assume that the system after cm or pm is 'as good as new'(perfect maintenance) or 'as bad as old'(minimal maintenance). But many maintenance activities may not result in these two extreme situations but in a complicated intermediate one. Therefore, perfect maintenance and minimal maintenance are not practical in many actual instances and so realistic imperfect maintenance should be modeled. For this study, various imperfect preventive maintenance models are investigated and analyzed. From the analysis of the imperfect maintenance models modeling methods and maintenance policies are arranged and presented some tables providing informations to the maintenance managers.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.23 no.1
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• pp.1-7
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• 2015

The aircraft maintenance demands a lot of aviation mechanics in urgent according to the high season and low season in seasonal demand adjusted, unplanned maintenance work such as AD (airworthiness directives) and troubleshooting of aircraft system fault. The advent of Super-Large Aircraft such as A380 with aircraft materials, power plant and avionics systems which were not in previous models must be expected to increase the complexity of the aircraft maintenance system. This study is intended to propose the development plan for formation of positive flexibility culture in aircraft maintenance organization through the review of previous research on flexibility culture of organization and through empirical research for bureaucratic and poor factors by the evaluation of flexibility culture level of domestic aircraft maintenance organization.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.2059-2063
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• 2004

Most power plants have operated many independent computerize systems for maintenance. Independence of systems have caused complexity of business process and inconvenience of computer system management. Because the equipment and material master data is not standardize and structurize, it is difficult to manage equipment maintenance history and material delivery. Especially equipment classification criterion is important for standardization of every maintenance information. It is necessary to integrate function of independent systems for business process simplification and rapid work flow. this paper provides equipment classification criterion design and system integration method with the case of live system development.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.215-217
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• 2013

The maintenance management in buildings has got more important by the increasing complexity of building sizes and use. Nowadays an expectation and a possibility of BIM technology become accepted as a new construction management method, therefore many studies and legal systems of it are being suggested actively. Although orders for BIM projects are supposed to be increasing, at present the BIM information accumulated from planning and design still doesn't have its continuity at the maintenance step after completion of construction in terms of LCC. It can't use the possibility that BIM originally has, and also causes some confusion in communication. This study analyzes and classifies required information in terms of BIM in the range of estimating repair costs of apartment buildings, as an example of a way to use BIM information at the maintenance step.

• Journal of The Korean Association of Information Education
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• v.2 no.2
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• pp.260-268
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• 1998

In this paper, I propose a metric model for measuring complexity of Web documentations which are wrote by HTML and XML. The complexity of Web documentation has effect on documentation understandability which is an important metric in maintenance and reusing of Web documentation. The understandable documents have more effect on WEI. The proposed metric uses the entropy to represent the degree of information flows between Web documentations. The proposed documentation complexity measures the information flows in a Web document based on the information passing relationship between Web document files. I evaluate the proposed metric by using the complexity properties proposed by Weyuker, and measure the document complexity. I show effectiveness of analyzing the correlation between the number of document file and document complexity.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.232-233
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• 2015

The maintenance management in buildings has got more important by the increasing complexity of building sizes and use. Nowadays an expectation and a possibility of BIM technology become accepted as a new construction management method, therefore many studies and legal systems of it are being suggested actively. Although orders for BIM projects are supposed to be increasing, at present the BIM information accumulated from planning and design still doesn't have its continuity at the maintenance step after completion of construction in terms of LCC. Therefore according to bim information, we set a goal of developing apartment maintenance system which is able to maintain by user and administrator viewpoint.