• Korean Journal of Construction Engineering and Management
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• v.6 no.4 s.26
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• pp.80-90
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• 2005

Activity durations retain probabilistic and stochastic natures due to diverse factors causing the delay or acceleration of activity completion. These natures make the final project duration to be a random variable. These factors are the major source of financial risk. Extending the Stochastic Project Scheduling Simulation system (SPSS) developed in previous research; this research presents a method to estimate how the final project duration behaves when activity durations change randomly. The final project cost is estimated by considering the fluctuation of indirect cost, which occurs due to the delay or acceleration of activity completion, along with direct cost assigned to an activity. The final project cost is estimated by considering how indirect cost behaves when activity duration change. The method quantifies the amount of contingency to cover the expected delay of project delivery. It is based on the quantitative analysis to obtain the descriptive statistics from the simulation outputs (final project durations). Existing deterministic scheduling method apply an arbitrary figures to the amount of delay contingency with uncertainty. However, the stochastic method developed in this research allows computing the amount of delay contingency with certainty and certain degree of confidence. An example project is used to illustrate the quantitative analysis method using simulation. When the statistical location and shape of probability distribution functions defining activity durations change, how the final project duration and cost behave are ascertained using automated sensitivity analysis method

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.85-96
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• 2004

This paper is to study on the decommissioning cost estimation for nuclear facilities of advanced nuclear organizations and countries for deriving the cost factors to be taken considerations into accomplishing decommissioning projects. Of cost categories producing the factors of decommissioning costs, dismantling and waste processing & disposals activities are examined to increase the its costs. Of labor, materials and other costs categories, labor costs are summarized to have overall majorities in the decommissioning cost factors. The main parameters of all factors affecting the decommissioning costs are analyzed as work difficulty, regional labor costs, peripheral cost, disposal cost and final burial costs.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.2
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• pp.218-226
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• 2023

In Korea, we still use function point based cost estimations for software size and cost of a project. The current problem is that we make difficultly calculating function points with requirements and also have less accurate. That is, it is difficult for non-experts to analyze requirements and calculate function point values with them, and even experts often derive different function points. In addition, all stakeholders strongly make the validity and accuracy of the function point values of the project before /after the development is completed. There are methods for performing function point analysis using source code [1][2][3][4] and some researchers [5][6][7] attempt empirical verification of function points about the estimated cost. There is no research on automatic cost validation with source code after the final development is completed. In this paper, we propose automatically how to calculate Function Points based on natural language requirements before development and prove FP calculation based on the final source code after development. We expect validation by comparing the function scores calculated by forward engineering and reverse engineering methods.

• IE interfaces
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• v.6 no.1
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• pp.87-97
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• 1993

In this paper, the plant layout planning is optimized at the K-area of the K-airline. The K-area includes 15 activies. The initial solution is found qualitatively by designing a space relationship diagram for the relationship. The cost of material handling is minimized by finding the final layout plan using CRAFT. In comparing to the master plan of K-airline, the final layout plan in this research can reduce the cost of material handling by 52%.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.766-771
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• 2007

In this research, we were going to make the function which can forecast the operating cost of metropolitan railroad that is performing a role of assistant highway within the city. In order to do this, based on service records of subway line 1st to 8th in Seoul, we extracted 23 variables which can affect to the operating cost, and we selected the final variable for estimate the function of operating cost from correlation among variables and influence analysis. Then, we performed regression analysis by stages using final variable. 6 independent variables are chosen for presuming the operating cost, and we obtained the final 3 variables (quantity of holding motor cars, peak quantity of possessed motor cars, and quantity of stations) as a result of regression analysis. Through this research, function of operating cost of metropolitan railroad has better applicability than existing preliminary validity, and it is used by further preliminary validity investigation and master plan or validity investigation which is accompanied by operation designing, thus we expect that it could make a great contribution to the priority order of investment for metropolitan railroad or process of policy decision.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.3
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• pp.241-244
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• 1991

An experiment was conducted to investigate the nutritional and economic effects of complete replacement of maize with sun-dried cassava (SDC) in the diet of broiler chickens raised from one day of age to seven weeks. The complete replacement of maize by SDC resulted in a 10 percent reduction (p<0.05) in final bodyweights (1.91 vs 1.72 kg); and a 5 percent reduction (p>0.05) in average feed intake (4.01 vs 3.81 kg). Feed efficiency was not affected (p > 0.05). Cost per kilogramme of feed was reduced by nearly 30 percent and cost per kilogramme of bodyweight gain lowered by about 26 percent by using SDC diet. Relative profit return after accounting for cost of feed and cost of day old chick was higher by 11 percent on the SDC diet. It was concluded that despite the reduction in final bodyweight, the attractive economic return obtained from using SDC, a locally produced ingredient, may be justified in place of maize which is imported.

• Journal of Astronomy and Space Sciences
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• v.25 no.4
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• pp.361-374
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• 2008

Recently, satellite formation flying has been a topic of significant research interest in aerospace society because it provides potential benefits compared to a large spacecraft. Some techniques have been proposed to design optimal formation trajectories minimizing fuel consumption in the process of formation configuration or reconfiguration. In this study, a method is introduced to build fuel-optimal trajectories minimizing a cost function that combines the total fuel consumption of all satellites and assignment of fuel consumption rate for each satellite. This approach is based on collocation and nonlinear programming to solve constraints for collision avoidance and the final configuration. New constraints of nonlinear equality or inequality are derived for final configuration, and nonlinear inequality constraints are established for collision avoidance. The final configuration constraints are that three or more satellites should form a projected circular orbit and make an equilateral polygon in the horizontal plane. Example scenarios, including these constraints and the cost function, are simulated by the method to generate optimal trajectories for the formation configuration and reconfiguration of multiple satellites.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.11
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• pp.2800-2812
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• 2012

The purpose of this study was to examine the syllable-word boundary misalignment cost on word segmentation in Korean continuous speech. Previous studies have demonstrated the important role of syllabification in speech segmentation. The current study investigated whether the resyllabification process affects word recognition in Korean continuous speech. In Experiment I, under the misalignment condition, participants were presented with stimuli in which a word-final consonant became the onset of the next syllable. (e.g., /k/ in belsak ingan becomes the onset of the first syllable of ingan 'human'). In the alignment condition, they heard stimuli in which a word-final vowel was also the final segment of the syllable (e.g., /eo/ in heulmeo ingan is the end of both the syllable and word). The results showed that word recognition was faster and more accurate in the alignment condition. Experiment II aimed to confirm that the results of Experiment I were attributable to the resyllabification process, by comparing only the target words from each condition. The results of Experiment II supported the findings of Experiment I. Therefore, based on the current study, we confirmed that Korean, a syllable-timed language, has a misalignment cost of resyllabification.

• Computers and Concrete
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• v.26 no.4
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• pp.309-316
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• 2020

The application of multi-variable adaptive regression spline (MARS) in predicting he long-term compressive strength of a concrete with various admixtures has been investigated in this study. The compressive strength of concrete specimens, which were made based on 24 different mix designs using various mineral and chemical admixtures in different curing ages have been obtained. First, The values of fly ash (FA), micro-silica (MS), water-reducing admixture (WRA), coarse and fine aggregates, cement, water, age of samples and compressive strength were defined as inputs to the model, and MARS analysis was used to model the compressive strength of concrete and to evaluate the most important parameters affecting the estimation of compressive strength of the concrete. Next, the proposed equation by the MARS method using particle swarm optimization (PSO) algorithm has been optimized to have more efficient equation from the economical point of view. The proposed model in this study predicted the compressive strength of the concrete with various admixtures with a correlation coefficient of R=0.958 rather than the measured compressive strengths within the laboratory. The final model reduced the production cost and provided compressive strength by reducing the WRA and increasing the FA and curing days, simultaneously. It was also found that due to the use of the liquid membrane-forming compounds (LMFC) for its lower cost than water spraying method (SWM) and also for the longer operating time of the LMFC having positive mechanical effects on the final concrete, the final product had lower cost and better mechanical properties.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.3
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• pp.97-105
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• 2011

Previous researches have focused on the efficiency of project execution and the satisfaction of internal customers In view of the fact that a project is successful if any defects are not found in the short-term performance test of the project final outcome. To execute a project that both internal customer and external customer are satisfied in terms of longer-term benefit perspective, the project claim costs (PCC) which may occur for the warranty period of the project final outcome should be considered. We propose a model included PCC to the linear programming between time and cost to expedite a project and perform the validity test by applying the model to an example project. This model and related procedure will contribute to overall project activities' cost reduction by taking preventive actions for PCC.