• Korean Journal of Construction Engineering and Management
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• v.13 no.3
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• pp.14-24
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• 2012

Recently, a delivery system has been rapidly changed in the global construction market. Also, construction projects are becoming bigger and more technology-intensive. A lot of projects have been delivered by Design-Build(DB) System; from the standpoint of cost, approximately 40% of delivered constructions by a Public Procurement Service were DB in 2009. Nevertheless, the achievement has not surpassed our expectations on management of the project cost. On the characteristic of DB, the reasons why that happens are that projects contract have been signed after the Design Development Stage; the insufficient review about new technology and up-to-date construction methods; a lack of discussion in process of design. Those reasons cause a risk of increasing Cost of the projects. In order to solve these problems, it is desirable to find Cost-increasing factors in promoting the projects and select on the order of priority for Risk-Factor with careful management. Therefore, this study analyzed the weight of each phase of the project on the authority of properties of DB project, and identified Risk-factors which is increasing the cost on the aspect of project management. Based on this analysis, the impact assessment of Risk-factor is evaluated through the Failure Mode and Effect Analysis(FMEA).

• Korean Journal of Construction Engineering and Management
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• v.15 no.3
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• pp.113-119
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• 2014

Recently, the demand on the practical application of life-cycle cost effectiveness for design and rehabilitation of structure is rapidly growing unprecedently in engineering practice. Accordingly, in the 21st century, it is almost obvious that life-cycle cost together with value engineering will become a new paradigm for all engineering decision problems in practice. However, in spite of impressive progress in the researches on the LCC, the most researches have only focused on the Deterministic or Probabilistic LCC analysis approach (Level-1 LCC Model) at design stage. Thus, the goal of this study is to develop a practical and realistic methodology for the Lifetime risk based Life-Cycle Cost (LCC)-effective optimum decision-making at design stage.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.4
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• pp.413-427
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• 2006

It is necessary to study and develop guidelines for providing comfort and health indoor air quality for office workers since air-tight envelope system of current office building may cause poor indoor air quality. The purpose of this study is to propose guideline for volatile organic compounds in office base on the field study, human health risk assessment and cost-benefit analysis. The field study was conducted to survey the concentrations of volatile organic compounds in indoor air of 69 offices from June to September, 2005 in Seoul and Gyeonggi-do. The rate of excess to guideline of volatile organic compounds in indoor air of new apartment on the Ministry of Environment in Korea(MOE) was surveyed 37.6% for benzene, 6.8% for toluene, and 1.5% for ethylbenzene. As the result of human health risk assessment, mean cancer risk did not exceed 10-6 which is guideline of US.EPA. Also, total hazard index did not exceed 1 which is guideline of US.EPA. Through the cost-benefit analysis of angle on the social-economics to verify the necessary to establish the standards of volatile organic compounds for improvement and development of indoor air quality in office, the present value of benefit was higher than the present value of cost. With the above considerations in mind, it is suggested that the field study for indoor air quality in offices should be expanded and human health risk assessment and cost-benefit analysis be performed th offer scientific data for decision-making of policy for improvement and management of indoor air quality in office.

• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.61-66
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• 2003

The objective of this study is to develop a Cost-Benefit analysis system which would help us to make optimal decision among safety investment alternatives, calculating and comparing costs and benefits for facilities in chemical plants. So, the accident frequency analysis module and the accident damage prediction module were developed for estimating quantitative risks in chemical facilities, and domestic societal risk criterion was presented after the comparative analysis of major industrial cases and societal risk criteria of advanced countries like the Netherlands, Australia, U.S.A., U.K., and Germany. Also, the Cost-Benefit Analysis System which compares the safety investment alternatives based on their deduced net present values was developed through the selection of proper cost and benefit items by field studies

• Journal of Korean Academy of Nursing Administration
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• v.17 no.4
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• pp.516-523
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• 2011

Purpose: The purpose of this study was to examine the causal relationships of perceived risk, satisfaction, switching cost and loyalty in outpatient health services. Method: A survey using a structured questionnaire was conducted with 393 hospital outpatients. The analysis of data was done with both SPSS Win 17.0 for descriptive statistics and AMOS 18.0 for structural equation model. Results: The causal model yielded Chi-square=31.44 (p=<.001), df=4, GFI=.98, AGFI=.87, CFI=.97, RMSR=.04, NFI=.96, IFI=.97 and showed relatively good fit indices. Perceived risk had a significant direct effect on customer satisfaction. Customer satisfaction, financial switching cost and relational switching cost had significant direct effects on customer loyalty. Perceived risk and customer satisfaction had significant indirect effects on customer loyalty. Conclusion: These results suggest that we should decrease the perceived risk and improve the customer satisfaction and switching cost to retain loyal customers. Further study with both a larger sample from various hospitals and a longitudinal design is necessary.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.534-541
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• 2011

Risk evaluation approaches for bidding on international construction projects are typically partitioned into three stages: country selection, project classification, and bid-cost evaluation. However, previous studies are frequently under attack in that they have several crucial limitations: 1) a dearth of studies about country selection risk tailored for the overseas construction market at a corporate level; 2) no consideration of uncertainties for input variable per se; 3) less probabilistic approaches in estimating a range of cost variance; and 4) less inclusion of covariance impacts. This study thus suggests a three-staged risk evaluation model to resolve these inherent problems. In the first stage, a country portfolio model that maximizes the expected construction market growth rate and profit rate while decreasing market uncertainty is formulated using multi-objective genetic analysis. Following this, probabilistic approaches for screening bad projects are suggested through applying various data mining methods such as discriminant logistic regression, neural network, C5.0, and support vector machine. For the last stage, the cost overrun prediction model is simulated for determining a reasonable bid cost, while considering non-parametric distribution, effects of systematic risks, and the firm's specific capability accrued in a given country. Through the three consecutive models, this study verifies that international construction risk can be allocated, reduced, and projected to some degree, thereby contributing to sustaining stable profits and revenues in both the short-term and the long-term perspective.

• Korean Journal of Construction Engineering and Management
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• v.13 no.2
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• pp.147-155
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• 2012

Recently, various construction projects are invested with plenty capital, manpower and resources. The advanced methods of the construction management is introduced to Korea. However, the cases which get involved in excessive cost frequently occur. We can explain it means that the cost management in the entire phases and the risk factors in its works has not been done yet as expected. Thus, it is necessary to unearth risk factors relative to cost management and analyse them for preventing cost-increasing and the success of projects. In this point of view, this study aims to identify the risk factors of the cost management focused on pre-construction stages from the perspective of construction management which is possible to take part in the whole phases and works in cost management. Also, the impact priority and grade of risk factors to cost-increasing are evaluated by using FMEA.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.2
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• pp.158-170
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• 2009

This paper considers how the optimal export level is influenced by export risk, the degree of risk-averseness for exporting firms, and those firms' cost structure. In addition, export insurance is incorporated into some simple theoretical model to analyze the optimal export level. This paper applies genetic algorithm simulation to show that the exporting firms'risk-averseness do not affect the optimal export decision while export risk and cost function characteristic have relatively more significant effects on the optimal export level. Finally, our findings suggest that the most influential factor for the optimal export levels seems to be the monopoly power of exporting firms.

• Korean Journal of Construction Engineering and Management
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• v.18 no.3
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• pp.105-116
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• 2017

In recent years, large Korean construction companies have suffered serious losses in their overseas business. Many practitioners and researchers have analyzed causes of cost overrun in these projects. However, these arguments have not been empirically verified based on acutal project cases. This study investigated cost overrun rate, contingency, allowance, predicted risk before bidding, and actual and residual risk after award in the 67 international infrastructure projects conducted by 13 large construction companies. The causes of cost overruns are derived as follows. First, they identified the possibility of cost overrun to some extent before the bidding, but did not reflect the enough risk money to bid price. In particular, this behavior was more severe in badly cost-overrun projects. Second, the causes of cost overrun were more influenced by external environmental risk than internal capability risk. However, the internal risk in badly cost-overrun projects was relatively high compared to cost-underrun projects. Third, badly cost-overrun projects failed to mitigate risk. However, cost underrun projects were affected more by low exterior risk conditions than by well mitigated risk. This study provides more informed knowledge in controlling project costs in international infrastructure projects.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.2
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• pp.134-145
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• 2015

Objectives: An objective of this study was to perform a risk assessment and social cost-benefit analysis for revising permissible exposure limits for seven substances: Nickel(Insoluble inorganic compounds), benzene, carbon disulfide, formaldehyde, cadmium(as compounds), trichloroethylene, touluene-2,4-diisocyanate. Materials and Methods: The research methods were divided into risk and hazard assessment and cost-benefit analysis. The risk and hazard assessment for the seven substances consists of four steps: An overview of GHS MSDS(1st), review of document of ACGIH's TLVs (2nd), comparison between international occupational exposure limits and domestic permissible exposure limits(3rd), and analysis of excess workplace and excess rate for occupational exposure limits based on previous work environment measurement data(4th). Total cost was estimated using cost of local exhaust ventilation, number of excess workplace and penalties for exceeding a permissible exposure limit. On the other hand, total benefit was calculated using the reduction rate of occupational disease, number of workplaces treating each substance and industrial accident compensation. Finally, the net benefit was calculated by subtracting total cost from total benefit. Results: All the substances investigated in this study were classified by CMR(Carcinogens, Mutagens or Reproductive toxicants) and their international occupational exposure limits were stricter than the domestic permissible exposure limits. As a result of excess rate analysis, trichloroethylene was the highest at 11%, whereas nickel was the lowest at 0.5%. The excess rates of all substances except for trichloroethylene were observed at less than 10%. Among the seven substances, the total cost was highest for trichloroethylene and lowest for carbon disulfide. The benefits for the seven substances were higher than costs estimated based on strengthening current permissible exposure limits. Thus, revising the permissible exposure limits of the seven substances was determined to be acceptable from a social perspective. Conclusions: The final revised permissible exposure limits suggested for the seven substances are as follows: $0.2mg/m^3$ for nickel, 0.5 ppm(TWA) and 2.5 ppm(STEL) for benzene, 1 ppm(TWA) for carbon disulfide, $0.01mg/m^3$(TWA) for cadmium, 10 ppm(TWA) and 25 ppm(STEL) for trichloroethylene, 0.3 ppm(TWA) for formaldehyde, and 0.005 ppm(TWA) and 0.02 ppm(STEL) for toluene diisocynate(isomers).