• Journal of Software Assessment and Valuation
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• v.16 no.1
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• pp.27-36
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• 2020

The software development cost appraisal is treated as a part of the program completion appraisal, and the software engineering methodology is applied. In particular, software cost estimation techniques have been actively applied. For more information about the software development costs calculation, we can refer to the "SW cost estimation guide". Although successful appraisal of a number of development costs based on the guide has been processed, but a number of cases requiring discussion of appraisal results have been discovered. In this study, we propose a use case-based size estimation method to maintain the accuracy and consistency of size estimation. As a result of performing performance evaluation of the proposed method in an environment similar to the development cost appraisal case, it was proved that the accuracy was improved over the existing function points method.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1693-1705
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• 2013

To restore old aqueduct in Korea which is a irrigation bridge to supply water in paddy field area, it is needed to estimate approximate costs of restoration because the basic design for estimation of construction costs is often ruled out in current system. In this paper, estimating models of construction costs were developed on the basis of performance data for restoration of RC aqueduct bridges since 2003. The regression analysis (RA) model and case-based reasoning (CBR) model for the estimation of construction costs were developed respectively. Error rate of simple RA model was lower than that of multiple RA model. CBR model using genetic algorithm (GA) has been applied in the estimation of construction costs. In the model three factors like attribute weight, attribute deviation and rank of case similarity were optimized. Especially, error rate of estimated construction costs decreased since limit ranges of the attribute weights were applied. The results showed that error rates between RA model and CBR models were inconsiderable statistically. It is expected that the proposed estimating method of approximate costs of aqueduct restoration will be utilized to support quick decision making in phased rehabilitation project.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.19 no.2
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• pp.67-81
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• 1990

The objective of this is to develop a practical software package to calculate annual energy consumption of HVAC (Heating Ventilating, and Air Conditioning) System in a building. It can quickly estimate loads and energy consumption, and have a function of economic analysis through the estimation of operating cost. Techniques of save energy consumption used in a building are necessary from the stage of design process to operation. The single most significant task is on HVAC Systems. Their installation costs, and related operating costs have enormous influence upon initial and maintenance costs. HVAC designers and engineers now have a wide variety of software choices available, but only a few of them have been developed in this country and no source program has been disclosed. Neither load culculation nor estimation of energy consumption is systematically made by the domestic HVAC design firms. Even though computer improved over the years with a trend of large scale load calculation and system selection through simulaion, the utilization of software nowadays does not make good progress due to lack of working environment. Therefore, it is necessary to develop a practical software package with which load calculation can be made with ease and kind manner. This study concerns the development of a software package which makes it possible to design HVAC system and save energy consumption in operation. The algorithm used in this program is a Modified Bin Method widely known as a simplified energy analysis means.

• Journal of the Korean Operations Research and Management Science Society
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• v.18 no.1
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• pp.1-18
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• 1993

The family disaggregation model of hierarchical production planning (HPP) is the problem of (0 -1) mixed integer programming that minimizes the total sum of setup costs and inventory holding costs over the planning horizon. This problem is hard in a practical sense since optimal solution algorithms have failed to solve it within reasonable computation times. Thus effective familoy disaggregation algorithm should be developed for HPP. The family disaggregation algorithm developed in this paper consists of the first stage of finding initial solutions and the second stage of improving initial solutions. Some experimental results are given to verify the effectiveness of developed disaggregation algorithm.

• Environmental Engineering Research
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• v.12 no.5
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• pp.197-200
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• 2007

Advanced control is getting increasingly demanded in water and wastewater treatment systems. Various case studies have shown significant savings in operating costs, including energy costs, and remarkably short payback times. It has been demonstrated that instrumentation, control and automation (ICA) may increase the capacity of biological nutrient removing wastewater treatment plants by 10-30% today. With further understanding and exploitation of the mechanisms involved in biological nutrient removal the improvements due to ICA may reach another 20-50% of the total system investments within the next 10-20 years. Disturbances are the reason for control of any system. In a wastewater treatment system they are mostly related to the load variations, but many disturbances are created also within the plant. In water supply systems some of the major disturbances are related the customer demand as well as to leakages or bursts in the pipelines or the distribution networks. Hardly any system operates in steady state but is more or less in a transient state all the time. Water and energy are closely related. The role of energy in water and wastewater operations is discussed. With increasing energy costs and the threatening climate changes this issue will grow in importance.

• Journal of Biosystems Engineering
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• v.19 no.3
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• pp.258-273
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• 1994

In this study, an expert system named ESMEF (Expert System for Mechanized Entrusted Farming) was developed. The function of ESMEF is to provide the various data and informations for entrusted farming such as farm machinery management data, mechanization systems by farm sizes, number of units and sizes of machinery needed, machinery replacement analysis, mechanization costs analysis. Mechanization systems were selected by ESMEF for different farming sizes of Chungnam Province and an economic analysis was conducted as an example. The results showed that the farm machinery purchasing costs were 1,344~4,829 thousand won per ha and there was no significant difference for farm sizes above 60 ha. The total annual machinery costs were 3,595~4,537 thousand won per ha, and a minimum cost was appeared for farm size of l00ha at first. According to this analysis, an optimum entrusted farming size would be 100ha by the present available farm machinery systems.

• Journal of the Korea Institute of Building Construction
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• v.12 no.5
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• pp.518-527
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• 2012

This study uses a hybrid estimation tool for effective cost data management of building projects, and develops a realistic cost estimation model. The method makes use of newly available information as the project progresses, and project cost and percentage progress are analyzed and used as inputs for the developed system. For model development, case-based reasoning (CBR) is proposed, as it enables complex nonlinear mapping. This study also investigates analytic hierarchy process (AHP) for weight generation and applies them to a real project case. Real case studies are used to demonstrate and validate the benefits of the proposed approach. By using this method, an evaluation of actual project performance can be developed that appropriately considers the natural variability of construction costs.

• IE interfaces
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• v.18 no.2
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• pp.117-125
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• 2005

One of the primary means of achieving global competitiveness is to reduce the COPQ in our business units. Although the COPQ is not known precisely, it is known to be very high. Also, it may be underestimated by the hidden costs due to non-value added activities, such as potential lost sales, costs of redesign due to quality reasons, and extra manufacturing costs due to defects, etc. In any manufacturing or service operation, all actions and resource expenditures of a company should be focused on creating value for customers. Any activity or resource of not creating the value for customers could be regarded as waste, which consequently causes the COPQ. In this paper, a management system is developed for evaluating and reporting the COPQ in our business units, based on the Six Sigma DMAIC (Define, Measure, Analyze, Improve, Control) roadmap.

• KCID journal
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• v.5 no.2
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• pp.52-60
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• 1998

Seawater desalination means conversion of seawater to freshwater usually for consumption by human beings. This study was conducted to evaluate production costs of freshwater occuring from different types of water resources development facilities such as v

• Nutrition Research and Practice
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• v.9 no.4
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• pp.400-403
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• 2015

BACKGROUND/OBJECTIVES: By the year 2050, thirty-eight percent of the Korean population will be over the age of 65. Health care costs for Koreans over age 65 reached 15.4 trillion Korean won in 2011, accounting for a third of the total health care costs for the population. Chronic degenerative diseases, including coronary heart disease (CHD), drive long-term health care costs at an alarming annual rate. In the elderly population, loss of independence is one of the main reasons for this increase in health care costs. Korean heath policies place a high priority on the prevention of CHD because it is a major cause of morbidity and mortality. SUBJECTS/METHODS: This evidence-based study aims to the estimate potential health care cost savings resulting from the daily intake of omega-3 fatty acid supplementation. Potential cost savings associated with a reduced risk of CHD and the medical costs potentially avoided through risk reduction, including hospitalizations and physician services, were estimated using a Congressional Budget Office cost accounting methodology. RESULTS: The estimate of the seven-year (2005-2011) net savings in medical costs resulting from a reduction in the incidence of CHD among the elderly population through the daily use of omega-3 fatty acids was approximately 210 billion Korean won. Approximately 92,997 hospitalizations due to CHD could be avoided over the seven years. CONCLUSIONS: Our findings suggest that omega-3 supplementation in older individuals may yield substantial cost-savings by reducing the risk of CHD. It should be noted that additional health and cost benefits need to be revisited and re-evaluated as more is known about possible data sources or as new data become available.