• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.2
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• pp.171-177
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• 2016

Software reliability in the software development process is an important issue. Software process improvement helps in finishing with reliable software product. Infinite failure NHPP software reliability models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this study, reliability software cost model considering shape parameter based on life distribution from the process of software product testing was studied. The cost comparison problem of the Lomax distribution reliability growth model that is widely used in the field of reliability presented. The software failure model was used the infinite failure non-homogeneous Poisson process model. The parameters estimation using maximum likelihood estimation was conducted. For analysis of software cost model considering shape parameter. In the process of change and large software fix this situation can scarcely avoid the occurrence of defects is reality. The conditions that meet the reliability requirements and to minimize the total cost of the optimal release time. Studies comparing emissions when analyzing the problem to help kurtosis So why Kappa efficient distribution, exponential distribution, etc. updated in terms of the case is considered as also worthwhile. In this research, software developers to identify software development cost some extent be able to help is considered.

• Land and Housing Review
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• v.2 no.4
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• pp.415-427
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• 2011

This study is aiming at estimating the demolition cost of deterioration housing by the rational method in order to provide for the demolition and new build project of the rental multi-family housing of LH. We investigated the actual state of demolition construction and work process of small size housing, and analysed an actual condition of estimation for the demolition cost through an advice by the expert of construction cost estimate. Furthermore, the 'estimation standard for the predetermined amount', 'estimation standard for the disposal cost of construction wastes' and precedent studies in public construction work were considered. As one of results in this study, cost accounting system, breakdown system and construction cost for the demolition work based on the standard of estimate were proposed and the predetermined amount of demolition construction for the multi-family housing with 2 or 3 floors could be produced by them. Eventually, It is estimated that the demolition cost per a multi-family housing is about 18,331,000(won) and 104,000(won) per floorage($m^2$). To the details, the result indicated that the direct demolition cost needs about 14,339,000(won) per a multi-family housing and the consignment disposal cost of wastes needs 3,992,000(won) per one. The results of the study will be used as the fundamental data to estimate the project cost in the phase of budget establishment for demolition and new build project of the deteriorated rental multi-family housings, and also cost accounting system of demolition construction and breakdown system are expect to be used effectively at the ordering of public construction work.

• Korean Management Science Review
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• v.12 no.1
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• pp.111-124
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• 1995

With the increasing interest of reducing process variation, statistical process control has served the pivotal tool in most industrial quality programs. In this study, system analyses have been performed associated with a cost incorporated version of a process control, a quadratic loss-based X over bar control chart model. Specifically, two issues, the capital/research investments for improvement of a system and the precision of a parameter estimation, have been addressed and discussed. Through the analysis of experimental results, we show that process variability is seen to be one of the most important sources of loss and quality improvement efforts should be directed to reduce this variability. We further derive the results that, even if the optimal designs may be sensitive, the model appears to be robust with regard to misspecification of parameters. The approach and discussion taken in this study provide a meaningful guide for proper process control. We conclude this study with providing general comments.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.04a
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• pp.178-185
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• 1999

Minimum life-cycle cost helps to evaluate cost effectiveness of base-isolated bridges under specific condition. Life-cycle cost mainly consists of the initial construction cost and the expected damage cost. Damage cost estimation needs proper model of input ground motion failure probability evaluation method and limit states definition. We model the input ground motion as spectral density function compatible with the response spectra defined at each seismicity and site condition. Spectrum analysis and crossing theory is suitable for reseating calculation of failure probabilities in the process of cost minimization. Limit states of base-isolated bridges re defined for superstructure isolator and pier respectively The method is applied to both base-isolated bridges and conventional bridges under the same conditions to investigate cost effectiveness of base isolation in low and moderate seismic region. the results show that base-isolation of bridges are more effective in low and moderate seismic region and that the site effects on the economical efficiency may not be negligible in such a region.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.988-993
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• 2012

Energy and cost analysis of the preprocessing for carbon capture and storage transportation such as supercritical compression and liquefaction is done using chemical simulation model. Direct compression to supercritical phase (process 1-1), liquefaction and pumping (process 1-2), carbon dioxide compression and expansion as a refrigerant itself (process 2), usage of other refrigerant with compression and expansion (process 3-1), with absorption chiller (process 3-2), cascade refrigeration (process 3-2) have been simulated and evaluated. The specific cost is about 4 to 7 $/ton.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.49-50
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• 2023

Asbestos is a building material that has been actively used because of its excellent durability and heat resistance until 2009, when it was found to be a first-class carcinogen and prohibited in Korea. Currently, asbestos dismantling is an essential process in demolition of old buildings. Workers are likely to be exposed to asbestos in the process of dismantling and removing them, which causes various occupational diseases, suggesting related laws and work standards to ensure the safety of asbestos dismantling process. Accordingly, prior studies have been conducted to analyze the level of asbestos exposure and influencing factors occurring during work, but most of them are mainly concerning health issue while research on process risks considering field characteristics and safety aspects of the work processes is still insufficient. Therefore, this study aims to derive the process risks affecting the safety of workers based on the survey results of asbestos dismantling companies, and further proposed a cost calculation model taking those risks into account.

• Korean Journal of Construction Engineering and Management
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• v.11 no.4
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• pp.22-31
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• 2010

Because the estimated cost at early stage has great influence on decisions of project owner, the importance of early cost estimation is increasing. However, it depends on experience and knowledge of the estimator mainly due to shortage of information. Those tendency developed into case-based reasoning(CBR) method which solves new problems by adapting previous solution to similar past problems. The performance of CBR model is affected by attribute weight, so that its accurate determination is necessary. Previous research utilizes mathematical method or subjective judgement of estimator. In order to improve the problem of previous research, this suggests CBR schematic cost estimation method using genetic algorithm to determine attribute weight. The cost model employs nearest neighbor retrieval for selecting past case. And it estimates the cost of new cases based on cost information of extracted cases. As the result of validation for 17 testing cases, 3.57% of error rate is calculated. This rate is superior to accuracy rate proposed by AACE and the method to determine attribute weight using multiple regression analysis and feature counting. The CBR cost estimation method improve the accuracy by introducing genetic algorithm for attribute weight. Moreover, this makes user understand the problem-solving process easier than other artificial intelligence method, and find solution within short time through case retrieval algorithm.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.219-226
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• 2014

In this study, reliability software cost model considering shape parameter based on life distribution from the process of software product testing was studied. The shape parameter using the Erlang and Log-logistic model that is widely used in the field of reliability problems presented. The software failure model was used finite failure non-homogeneous Poisson process model, the parameters estimation using maximum likelihood estimation was conducted. In comparison result of software cost model based on the Erlang distribution and the log-logistic distribution software cost model, because Erlang model is to predict the optimal release time can be software, but the log-logistic model to predict to optimal release time can not be, Erlang distribution than the log-logistic distribution appears to be effective. In this research, software developers to identify software development cost some extent be able to help is considered.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.283-284
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• 2012

High-rise building construction has been increasing for the recent years and the construction process has become more complicated. This suggests a need for precise planning based on reliable data to prevent cost overruns and delays. However, the process planning is implemented based mainly on the experience of engineers that can result in critical damage in cost and time. Accurate productivity estimation and unit cost analysis must be considered important matter to prevent such disaster. This study estimates productivity and unit cost of curtain wall operations in high-rise building construction by simulation techniques and statistical methodologies. This study suggests a decision making methodology for the site personnel that enables to compare various combinations of productivity and unit cost based on reliable data that has been collected in actual construction sites. It is expected that this study contributes to the following research of developing an optimized construction performance assembling model for the site personnel.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.143-145
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• 2005

In this paper, an empirical study result on pattern estimation method is devoted to reveal underlying data patterns with a relatively reduced computational cost. Presented method performs crisp type clustering with given n number of data samples by means of the sequential agglomerative hierarchical nested model (SAHN). Conventional SAHN based clustering requires large computation time in the initial step of algorithm. To deal with this concern, we modified overall process with a partial approach. In the beginning of this method, we divide given data set to several sub groups with uniform sampling and then each divided sub data group is applied to SAHN based method. The advantage of this method reduces computation time of original process and gives similar results. Proposed is applied to several test data set and simulation result with conceptual analysis is presented.