• 한국노년학
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• v.27 no.2
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• pp.473-486
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• 2007

This study focused on the diversification of the elderly living cost estimate through statistical analysis method and Engel method(market basket method). The results of this study were as follows. First of all, due to Engel method, it has shown that the minimum living cost of aged couples was 566,478won on average of 2006, single aged men 306,210 won and single aged women 260,276 won. Secondly, according to the first way of statistical analysis, the minimum living cost of elderly couples was 860,043won, the standard was 1,018,669won and abundant 1,287,555won. The second way of that, the minimum(of elderly couples) was 694.916won, the standard 1,037,779won and abundant 1,556,551won. Those numbers included imputed rent. These results were changed to that the minimum is 435,416won, the standard 548,250won and the abundant 699,844won when imputed rent were excluded Moreover, it was also represented that the minimum of Engel method was between that of quasi-relative standard line and that of not imputed rent. Lastly, in the deprivation indicators method studied by Korea Institute for Health and Social Affair, it was concerned that an underestimation of elderly deprivation might have been got if some inappropriate data include. Given this study, it could not be judged that various estimating ways had been tried were consistency, but market-basket method was keenly needed. Market-basket method is being an absolute estimating way including only elderly data. Therefore, what is asking for first is - because other analysis can be limited by absolute estimating ways, particularly market-basket method - to be required systemic and all-arounded elderly living cost with more various ways.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.2
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• pp.117-124
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• 2005

This study tries to develop the models of measuring the level of product availability accommodated for features of specific customers dividing customers into VIP customers and general customers. Functions of costs that the models are composed of are cost of holding safety stock and cost of lost opportunities. The existing model of measuring the level of product availability which focused on cost of holding safety stock for VIP customers should be reinforced by considering cost of lost opportunities caused by general customers' quitting trades with a company. This study tries to present realistic solutions for problems in making decisions related to the total inventory. This study concludes that the model of the level of product availability meeting general customers' needs is more efficient according to increasing of a latent demand of the general customers who quit trades with a company and the cost of lost opportunities.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.04a
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• pp.387-393
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• 2001

Installing vibration control devices in the structure rises as a solution instead of increasing structural strength considering construction cost. Especially, viscoelastic dampers show excellent vibration control performance at low cost and are easy to install in existing structures compared with other control devices. Therefore, cost-effectiveness of structure with viscoelastic dampers needs to be evaluated. Previous cost-effectiveness evaluation method for the seismically isolated structure(Koh et al., 1999;2000)is applied on the building structure with viscoelastic dampers, which combines optimal design and cost-effectiveness evaluation for seismically isolated structures based on minimum life-cycle cost concept. Input ground motion is modeled in the form of spectral density function to take into account acceleration and site coefficients. Damping of the viscoelastic damper is considered by modal strain energy method. Stiffness of shear building and shear area of viscoelastic damper are adopted as design variables for optimization. For the estimation of failure probability, transfer function of the structure with viscoelastic damper for spectral analysis is derived from the equation of motion. Results reveal that cost-effectiveness of the structure with viscoelastic dampers is relatively high in how seismic region and stiff soil condition.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1132-1140
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• 2007

As it recently appears that Life Cycle Cost Analysis may be considered as new methodology for economic valuation of infrastructure many researches have been made to assess LCC(Life Cycle Cost) of each facility based on a reasonable methods. In general, LCC is composed of construction cost and expected maintenance repair cost. And especially, maintenance repair cost must be estimated to enhance the reliability through systematic and reasonable methods. However in Korea, because high speed railway steel bridges are recently constructed no direct statistical data are available for the account of the maintenance cost and then their maintenance characteristics are not linear yet. Therefore, the approach proposed in the paper utilizes a theoretical determination and degradation of the corrosion and fatigue of the bridges based on Rahgozar et al.(2006)'s model on fatigue notch factor considering into the corrosion to incorporate the corrosion effect into the fatigue strength reduction model. And then, the corresponding probability of failure is calculated in terms of the reliability index using S-N curve to formulate the fatigue limit state. Therefore, this paper proposes the minimum Life Cycle Cost through optimum maintenance plan analysis of high-speed railway steel bridges under construction. Finally, this paper reviews the proposed model in oder to confirm the applicability and feasibility by appling it to high speed railway steel bridges under construction

• Journal of the Korea Safety Management & Science
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• v.14 no.3
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• pp.119-126
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• 2012

Recently, the breakdown of online banking servers and the leakage of customer information give rise to much concern about the security of information systems in financial and banking companies in Korea. The enforcement of security for information system becomes much more important issue than earlier. However, the security reinforcement of information system is restricted by a budget. In addition, the activities' cost to secure information system from threatening are under uncertain circumstances and should be established by a human decision maker who is basically uncertain and vague. Thus, making the budget for information system is exposed to any extent of the risk for these reasons. First, we introduce brief fuzzy set theory and fuzzy AHP (Analytic Hierarchy Process) methodology. Then, the cost elements that comprise yearly budget are presented and the priorities among the cost elements are calculated by fuzzy AHP. The cost elements that are exposed to risk are evaluated from the both perspectives of the risk impact and risk occurrence possibility which are expressed as linguistic terms. To get information on the risk profiles-pessimistic, most likely, and optimistic-for each cost element, the evaluation is accomplished and the result is presented. At last, the budget ranges-minimum, mode, maximum-for each cost element are estimated with the consideration of the risk profiles.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.475-478
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• 2013

To carry out a one-off construction project successfully, effective and accurate early cost estimation is crucial, especially during the conceptual stage where very limited minimum information of construction project is given. As the level of accuracy of the early cost estimation has huge impacts on precise budgeting and cost management of a project, in other words, reducing the risk of a project, cost must be managed with special awareness. In an effort to improve the estimate accuracy of cost during the conceptual stage, this research introduces a Parameter Impact (PI) which can quantify weights of parameters and rank them; and PI development derived from the principle of impulse in physics is explicated. For a case study, 76 public apartment building cases in Korea are analyzed. To examine the validity of the proposed PI, a validation in terms of CBR applicability test and estimate accuracy comparisons using 10-nearest neighbor cases are carried out. The validation results support that the suggested PI can be applied in quantifying the weights of the parameters and CBR method for early cost estimation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.11
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• pp.3030-3049
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• 2023

With the development and wide application of hybrid network computing modes like cloud computing, edge computing and fog computing, the customer service requests and the collaborative optimization of various computing resources face huge challenges. Considering the characteristics of network environment resources, the optimized deployment of service resources is a feasible solution. So, in this paper, the optimal goals for deploying service resources are customer experience and service cost. The focus is on the system impact of deploying services on load, fault tolerance, service cost, and quality of service (QoS). Therefore, the alternate node filtering algorithm (ANF) and the adjustment factor of cost matrix are proposed in this paper to enhance the system service performance without changing the minimum total service cost, and corresponding theoretical proof has been provided. In addition, for improving the fault tolerance of system, the alternate node preference factor and algorithm (ANP) are presented, which can effectively reduce the probability of data copy loss, based on which an improved cost-efficient replica deployment strategy named ICERD is given. Finally, by simulating the random occurrence of cloud node failures in the experiments and comparing the ICERD strategy with representative strategies, it has been validated that the ICERD strategy proposed in this paper not only effectively reduces customer access latency, meets customers' QoS requests, and improves system service quality, but also maintains the load balancing of the entire system, reduces service cost, enhances system fault tolerance, which further confirm the effectiveness and reliability of the ICERD strategy.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.2
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• pp.113-127
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• 2007

In this study, a model to calculate the expected total construction cost is developed that simultaneously considers the rehabilitation cost related to the sliding of the caisson, the economic damage cost due to harbor shutdown in the event of excessive caisson sliding, and the economic damage cost due to temporal operational stoppage by excessive wave overtopping. A discount rate is used to convert the damage costs occurred at different times to the present value. The optimal cross-section of a caisson is defined as the cross-section that requires a minimum expected total construction cost within the allowable limit for the expected sliding distance of the caisson during the lifetime of the breakwater. Two values are used for the allowable limit: 0.3 and 0.1 m. It was found that the economic damage cost due to harbor shutdown by excessive caisson sliding is more critical than the rehabilitation cost of the caisson or the economic damage cost by excessive wave overtopping in the decision of the optimal cross-section. In addition, the optimal cross-section of the caisson was shown to be determined by the allowable limit for the expected sliding distance rather than the minimum expected total construction cost as a larger value is used for the threshold sliding distance of the caisson for harbor shutdown.

• Journal of the Korean Operations Research and Management Science Society
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• v.32 no.4
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• pp.51-60
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• 2007

In this study, we consider the minimum ADM problem which is the fundamental problem for the cost-effective design of SONET ADM embedded in WDM ring networks. To minimize the number of SONET ADMs, efficient algorithms for the routing and wavelength assignment are needed. We propose a mathematical model based on the graph theory for the problem and propose a branch-and-price approach to solve the suggested model effectively within reasonable time. By exploiting the mathematical structure of ring networks, we developed polynomial time algorithms for column generation subroutine at branch-and-bound tree. In a computer simulation study, the suggested approach can find the optimal solution for sufficient size networks and shows better performance than the greedy heuristic method.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.41-45
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• 2000

Geotube is made of permeable but soil-tight geotextile, hydraulically filled with soil include dredged sand and mud, which has been successfully applied in hydraulic and coastal engineering projects. Ceotube method is getting popular and being used a lot in many countries of the world because of the simplicity of the placement and construction, cost effectiveness and minimum impact on the environment, and enable to store & isolate contaminated materials as obtained by harbor dredging. Laboratory tests and field construction were performed to determine the design methodology and construction procedures. From the results of laboratory and field construction, the retention ratio of solid particle is a minimum 86%. The minimum permeability and the tensile strength of geotextile are $\alpha$ x 10$^{-4}$ cm/sec and 20t/m, respectively Also, based on the environmental test results, it can be concluded that this method does meet the Korean EPA standards.