• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.1
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• pp.55-67
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• 2010

Decision problem called an optimal release policies, after testing a software system in development phase and transfer it to the user, is studied. The applied model of release time exploited infinite non-homogeneous Poisson process. This infinite non-homogeneous Poisson process is a model which reflects the possibility of introducing new faults when correcting or modifying the software. The failure life-cycle distribution used generalized gamma type distribution which has the efficient various property because of various shape and scale parameter. Thus, software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement becomes an optimal release policies. In a numerical example, after trend test applied and estimated the parameters using maximum likelihood estimation of inter-failure time data, estimated software optimal release time.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.3
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• pp.9-17
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• 2010

Decision problem called an optimal release policies, after testing a software system in development phase and transfer it to the user, is studied. The applied model of release time exploited infinite non-homogeneous Poisson process. This infinite non-homogeneous Poisson process is a model which reflects the possibility of introducing new faults when correcting or modifying the software. The failure life-cycle distribution used superposition which has various intensity, if the system is complicated. Thus, software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement becomes an optimal release policies. In a numerical example, after trend test applied and estimated the parameters using maximum likelihood estimation of inter-failure time data, estimated software optimal release time. Through this study, in terms of superposition model and simply model, the optimal time to using superposition model release the software developer to determine how much could count will help.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.983-984
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• 2012

• Journal of Convergence for Information Technology
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• v.7 no.2
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• pp.67-76
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• 2017

Along with shortening the life cycle of software utilization and supporting various types of user functions, the importance of software architecture development has been emphasized recently. If a software architecture is developed flexibly and reliably for expansion to support new functionality, it can quickly cope with new market demands. This paper proposes an architecture design method based on design recovery of open source software to reuse the software in the development of sustainable software system. When using open source software to develop a software system based on software architecture, we can develop a software system rapidly and also can improve the reliability of the system because we use the already proven open source software in the development.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.2
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• pp.183-191
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• 2010

Decision problem called an optimal release policies, after testing a software system in development phase and transfer it to the user, is studied. The applied model of release time exploited infinite non-homogeneous Poisson process. This infinite non-homogeneous Poisson process is a model which reflects the possibility of introducing new faults when correcting or modifying the software. The failure life-cycle distribution used mixture which has various intensity, if the system is complicated. Thus, software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement becomes an optimal release policies. In a numerical example, after trend test applied and estimated the parameters using maximum likelihood estimation of inter-failure time data, estimated software optimal release time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.8
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• pp.1915-1925
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• 1998

The switching system software is large scale, real-time multi-task system which requires high reliability. The reliability assessment of large-scale software is very important for the success of software development project. For this raeson, the software quality measurement is much more important. In this paper, we have learned about the software reliability, metho of the analysis of failure data and estimation of software quality. To estimate the software reliability, using the failure data found during of the system test. We apply the two software reliability growth models, named Goel-Okumoto(G-O) and S-shaped model, to estimate the software reliability. Also, we compared with the results and we reviewed fully not only development cycle but validation and verification of the test data, for each software versions. This paper presents a software reliability model that suitale the software development project and the activeity of quality control for the switching system.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.225-229
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• 1996

In order to accomplish large-size information systems successfully, one of the most improtant factor is the system integration(SI) of individual software projects which consist of the systems. A developer of each project should consider aspects of SI through the development cycle, and a manager of the entire system should manage, control, and evaluate each from a SI point of view. In this research, management models for the system managers, development models for the developers of unit projects, and standardized output documents for the management and evaluation purpose are presented based on the SI concepts.

• Journal of the Korea Computer Industry Society
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• v.5 no.1
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• pp.9-18
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• 2004

Successful project planning relies on a good estimation of the manpower required to complete a project in addition to the schedule options that may be available. Existing software manpower estimation models present the total manpower and instantaneous manpower distribution for the software life cycle. Putnam's Rayleigh and Phillai et al.'s Gamma models present a model with assumption that the manpower is needed at the system delivery. This means that 40 percent of total manpower is applied at the software development, and the other 60% is applied during maintenance phase. However Warburton observes the manpower is needed during development phase with the peak at the completion of the software design phase. So, the existing models were not appropriate to be applied to practical projects. This paper suggests the Sigmoid model which does not consider the point of manpower peak to fix the problem above. The suggested model showed some improvement when practical data was applied. Therefore, the Sigmoid model can be used as alternative of Rayleigh and Gamma model to estimate distribution of manpower during software development phas.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.2
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• pp.363-374
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• 2015

Instrumentation and control(I&C) system has been mainly designed and operated based on analog technologies in existing Nuclear Power Plants(NPPs). However, As the development of Information Technology(IT), digital technologies are gradually being adopted in newly built NPPs. I&C System based on digital technologies has many advantages but it is vulnerable to cyber threat. For this reason, cyber threat adversely affects on safety and reliability of I&C system as well as the entire NPPs. Therefore, the software equipped to NPPs should be developed with cyber security attributes from the initiation phase of software development life cycle. Moreover through cyber security assessment, the degree of confidence concerning cyber security should be measured and if managerial, technical and operational work measures are implemented as intended should be reviewed in order to protect the I&C systems and information. Currently the overall cyber security program, including cyber security assessment, is not established on I&C systems. In this paper, we propose cyber security assessment methods in the Software Development Life Cycle by drawing cyber security activities and assessment items based on regulatory guides and standard technologies concerned with NPPs.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.1099-1100
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• 2005