• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.485-490
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• 2003

Nowadays the rapid change in construction environment getting more globalized and complicated has caused lots of unexpected risks from inside and out of the country, so more sophisticated construction management strategies are being strongly needed. This paper suggests a risk management model with which we can estimate the appropriate contingency by quantifying the amount of probable risks immanent in large construction projects, which have a high degree of uncertainty in the anticipation of the total construction cost. To develop the model, the risk factors that make cost variations are elicited based on the real data of the contingencies assigned to the past projects. Furthermore, the influential relationship of risk factors is structured by applying the CRM(Cost Risk Model) which is the synthetic model of Monte Carlo Simulation, Influence Diagram and Decision Tree. The ultimate outcome of this research can by validated by tile case study with a large construction project performed.

• Water for future
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• v.29 no.3
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• pp.197-205
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• 1996

Flow carrying capacity of water distribution systems is getting reduced by deterioration of pipes in the systems. The objective of this study is to develop a managerial decision-making model for the rehabilitation of water distribution systems with a minimum cost. The decisions made by the model also satisfy the requirements for the discharge and pressure at demanding nodes in the system. The replacement cost, pipe break repair cost, and pumping cost are considered in the economic evaluation of the decision along with the break ratio and interest ratio to determine the optimal replacement time for each pipe. Then, the hydraulic integrity of the water distribution system is checked for the decision by a pipe network simulator, KYPIPE, if the discharge and pressure requirements, the decision made for the optimal replacement time is revised until the requirements are satisfied. The model is applied to an existing water distribution system, the Metropolita Water Supply Project (1st Phase). The result shows that the decisions for the replacement time determined by the economix analysis are accepted as optimal and the hydraulic integrity of the system is in good condition.

• IE interfaces
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• v.15 no.2
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• pp.159-171
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• 2002

Data Warehouses integrate data from multiple heterogeneous information sources and transform them into a multidimensional representation for decision support applications. Data warehousing has emerged as one of the most powerful tools in delivering information to users. Most previous researches have focused on marketing, customer service, financing, and insurance industry. Further, relatively less research has been done on data warehouse systems in the complex manufacturing industry such as ship production, which is characterized complex product structures and production processes. In the ship production, data warehouse systems is a requisite for effective cost analysis because collecting and analysis of diverse and large of cost-related(material/production cost, productivity) data in its operational systems, was becoming increasingly cumbersome and time consuming. This paper proposes architecture of the data warehouse systems to support cost analysis in the ship production. Also, in order to illustrate the usefulness of the proposed architecture, the prototype system is designed and implemented with the object of the enterprise of producing a large-scale ship.

• Journal of the Korean association of regional geographers
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• v.4 no.2
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• pp.79-94
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• 1998

This study begins with emphasis on the approach to public policy development and the extent to which a GIS framework can be used to evaluate projects objectively. This paper relates to public policy making and the use of GIS as a strategic management tool rather than the development of GIS technologies which has been the focus of attention since the advent of the first generation GIS systems in the 1960s. In order to consolidate a view towards public policy, the aim of this study is to show the advantages of using GIS to generate results which could be evaluated by cost and benefit analysis giving options of the alternative methods to estimate the feasibility of projects (both tangible and intangible) in a real public policy scenario. This study also reports that the tangible benefits associated with the GIS projects are better information processing, the easy analysis of data and the cost savings of map updates and printing, whilst the intangible benefits include quality decision making, and precise management of data through computing networks. In GIS context, the task of analysing and evaluating GIS projects is assumed in order to facilitate scientific and quantitative cost-benefit analysis. Previous methods of the cost-benefit analysis has not fully supported the evaluation of the intangible benefits and it has not been possible to make public policy realistic or scientifically understandable limiting decision makers in public domain. With the GIS decision makers are able to explore the potential of projects with this powerful decision supporting tool in practical application. On the basis of its potentials and limitations to cost-benefit analysis, therefore, it can be concluded that more flexible analysis and evaluation methodologies are needed to extend into the intangible benefits. In order to balance the evaluation of both quantitative and qualitative approaches on the cost-benefit analysis new or additional utilities will be required for the next GIS generation appraisal tool.

• Environmental Analysis Health and Toxicology
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• v.30 no.sup
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• pp.6.1-6.4
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• 2015

Objectives This study is conducted to estimate the cost paid by the public suffering from disease possibly caused by chemical and to examine the effect on public health. Methods Cost-benefit analysis is an important factor in analysis and decision-making and is an important policy decision tool in many countries. Cost-of-illness (COI), a kind of scale-based analysis method, estimates the potential value lost as a result of illness as a monetary unit and calculates the cost in terms of direct, indirect and psychological costs. This study estimates direct medical costs, transportation fees for hospitalization and outpatient treatment, and nursing fees through a number of patients suffering from disease caused by chemicals in order to analyze COI, taking into account the cost of productivity loss as an indirect cost. Results The total yearly cost of the diseases studied in 2012 is calculated as 77 million Korean won (KRW) per person. The direct and indirect costs being 52 million KRW and 23 million KRW, respectively. Within the total cost of illness, mental and behavioral disability costs amounted to 16 million KRW, relevant blood immunological parameters costs were 7.4 million KRW, and disease of the nervous system costs were 6.7 million KRW. Conclusions This study reports on a survey conducted by experts regarding diseases possibly caused by chemicals and estimates the cost for the general public. The results can be used to formulate a basic report for a social-economic evaluation of the permitted use of chemicals and limits of usage.

• Proceedings of the IEEK Conference
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• 2000.09a
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• pp.65-68
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• 2000

It is well-known that the decision rule in the mini-mum mean-squares-error decision feedback equalizer(MMSE-DFE) is biased, and therefore suboptimum with respect to error probability. We present a new family of algorithms that solve the bias problem in the adaptive DFE. A novel constraint, called the constant-norm con-straint, is introduced unifying the quadratic constraint and the monic one. A new cost function based on the constant-norm constraint and Lagrange multiplier is defined. Minimizing the cost function gives birth to a new family of unbiased adaptive DFE. The simula-tion results demonstrate that the proposed method in-deed produce unbiased solution in the presence of noise while keeping very simple both in computation and im-plementation.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.10a
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• pp.147-157
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• 2004

Enterprises and governments currently utilize COTS based information systems which are a kind of component based systems. Especially, COTS are widely utilized as information security systems and information systems including information security functions. This paper suggests an appropriate adaptation level of security functional components and a cost effective priority among them. To make a cost effective decision on adapting security functional components, this paper develops a hierarchical model of information security technologies and analyzes findings through multiple decision-making criteria.

• Management Science and Financial Engineering
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• v.21 no.1
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• pp.25-29
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• 2015

Recently much research efforts have focused on how to manage carbon emissions in logistics operations. This paper formulates a model to determine an optimal shipment size with aims to minimize the total cost consisting not only of inventory and transportation costs but also cost for carbon emissions. Unlike the literature assuming carbon emission factors as a given condition, we consider the emission factors as decision variables. It is allowed to make an investment in improving carbon emission factors. The optimal investment decision is shown to be of a threshold type with respect to unit investment costs. Moreover, the findings in this work provide insights on the various elements of the investment decision and their impacts.

• Journal of Information Technology Services
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• v.11 no.4
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• pp.69-85
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• 2012

This paper analyzes how IT adoption affects differently on the shippers' make-buy decision, depending on the changes through agency and coordination problems. Empirical findings are consistent with the theoretical predictions on the changes of shippers' decision, summarized as follows. First, while the adoption of agency-cost reducing IT leads to the increase in the proportion of private fleets, the adoption of coordination-cost reducing IT leads to the increase in proportion of for-hire carriage. Second, the extent of private fleets changes depends on the primary product type that trucks load, with products of important service task experiencing more increase. Third, the extent of for-hire carriage changes depends on the truck's trip distance, with long-trip trucks experiencing more increase. With the results, we present different policy implications from the conventionally advocated ones.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1134-1139
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• 2009

Haul routes for earthmoving operation need to be carefully selected because the decision on the haul routes could make a significant difference in the project's cost and time. This paper proposes a decision support system for improving productivity of earthmoving operation that helps construction managers choose the best haul routes of trucks based on time slots. Also, a methodology for optimal selection of haul routes considering traffic conditions and topographic conditions of the routes is explained. Raster data model is used to find an available shortest path based on cost weighted distance. A system was developed on a geographic information system environment for efficient database management and easy manipulation of graphical data. A real-world case study was conducted to verify the applicability of the proposed system.