• The Korean Journal of Applied Statistics
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• v.24 no.4
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• pp.597-607
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• 2011

Value at Risk(VaR) is being widely used as a simple tool for measuring financial risk. Although VaR has a few weak points, it is used as a basic risk measure due to its simplicity and easiness of understanding. However, it becomes very difficult to estimate the volatility of the portfolio (essential to compute its VaR) when the number of assets in the portfolio is large. In this case, we can consider the application of a dimension reduction technique; however, the ordinary factor analysis cannot be applied directly to financial data due to autocorrelation. In this paper, we suggest a dimension reduction method that uses the time-series factor analysis and DCC(Dynamic Conditional Correlation) GARCH model. We also compare the method using time-series factor analysis with the existing method using ordinary factor analysis by backtesting the VaR of real data from the Korean stock market.

• 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.

• Journal of the Korea Institute of Building Construction
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• v.16 no.6
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• pp.487-495
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• 2016

The losses of accidents in the construction industry was significantly increased during the past decades. Therefore, the study of risk management measures in the domestic construction has become very important, and the inherent risk factors need to derive and analyze them based on the quantified method. However, most studies on the construction risk are conducted finding on the qualitative way. This study analysis the accident records from actual construction sites as a quantities study. A correlation analysis and regression analysis are adopted to identify the risk factors and develop a model. The results of this study are expected to be evolve through the accumulated effect and verification of data in the future through continuous feedback.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.50-50
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• 2017

도시홍수의 잠재적 위험은 홍수경감계획이 발전됨에 따라 감소하지만, 침수피해 가능성은 도시화와 도시 확장에 따라 증가한다. 침수피해 가능성에 대한 사전 파악 및 위험도 분석은 대규모 침수재해 발생 시의 위기관리에도 도움을 준다. 또한, 경제적 피해에 대한 예측은 재해발생 후 복구 및 복원 작업에 필요한 자원 할당에 매우 유용하며, 잠재적 홍수 피해에 대한 예측은 장기적인 홍수경감계획과 재해관리에 필요하다. 본 연구에서는 다차원 침수해석 모형의 결과로 산정 가능한 침수심, 유속 등의 지표들을 복합적으로 고려하여 침수위험도를 산정하고, 침수 발생 위험이 있는 지역의 인문 사회 경제적 지표를 통해 피해 저감 및 복구성을 반영하기 위한 재해 취약인자를 선정하여 해당 지역에 대한 취약도를 산정하였다. 또한, 분석된 위험도와 취약도의 연산으로 통합리스크 분석을 실시하여 침수 발생 시 해당지역에 대한 피해 예상과 지역별 상대평가가 가능하도록 하였다. 위험도와 취약도 및 리스크 분석은 다양한 인자를 동시에 고려하기 위해 여러 개의 기준에 대한 선호도를 결정하거나 최적 대안을 선택하는 다기준의사결정(MCDM)기법을 적용하였으며, MCDM기법 중 보편적으로 많이 이용되는 TOPSIS기법을 적용하였다. 이러한 리스크 분석은 우리나라 전체, 특정 시도, 시군구, 읍면동 간의 침수피해와 관련한 상대적 비교 평가가 가능하며, 대응 및 대비의 관점에서 저감 대책 수립의 우선 지역을 도출하는 데 활용될 수 있을 것이며, 침수피해 발생 후, 리스크가 큰 지역에 대해 우선적으로 복구 조치가 이뤄질 수 있을 것이다. 또한, 한정된 지자체 예산 안에서 도시홍수 피해 경감 대책 수립을 위한 의사결정에 활용될 수 있을 것으로 판단된다.

• Korean Journal of Construction Engineering and Management
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• v.12 no.4
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• pp.139-148
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• 2011

u-City projects are different with the existing urban development projects progress via convergence with IT technology. Therefore, it inheres many risk factors more than the existing development projects as including more complexity and variety. The risk management system to systematically manage those risks which get identified and quantified is required. Especially, the planning phase that is appeared the various forms has a large effect on the success of the business. However, the management of risk factors remains in the passive form. So the problems on u-City project in the planning phase and risk factors of existing development business were analyzed for the continuous growth and the successful performance of u-City project, and those risk factors was identified and quantified by using statistical technique. In the results of it, the core risk factors were obtained through which way and the basis for the effective risk management in u-City business is provided.

• Tunnel and Underground Space
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• v.23 no.4
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• pp.319-325
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• 2013

The objective of this study is to assess risks which might occur in connection with the storage of the highly compressed air in underground opening. Risk factors were selected throughout literature survey and analysis for the characteristic of CAES. Large risk factors were categorized in three components; planning and design phase, construction phase, and operation & maintenance phases. Large category was composed of 8 medium risk groups and 24 sub-risks. AHP technique was applied in order to analyze the questionnaires answered by experts and high-risk factors were selected by evaluating the relative importance of risks. AHP analysis showed that the operation & maintenance phases are the highest risk group among three components of large category and the highest risk group of eight medium risk groups is risk associated with the quality and safety. Risk having the highest risk level in 24 sub-risks is evaluated to be a failure of tightness security of inner containment storing compressed air.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.635-647
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• 2006

Korean construction companies first advanced to the international markets in 1960's and so far have brought more than 4,900 projects which account for 193 billion dollars approximately. With the large increase of national employment and income being followed by the achievement, Korea's construction industry has made an enormous contribution to the improvement of domestic economy for the last 40 years. However, recently the increased risk in international markets as well as the sharpening competition with foreign companies promising in terms of advanced technologies and low labor cost have been driving Korean construction away from the market shares. According to ENR (Engineering News Record, 1994~2003), it is revealed that 15.1% of top 225 global contractors are suffering from loss in international construction markets. This phenomenon is largely due to the highly uncertain characteristics of international projects, which are inherently exposed to various and complicated risky situations. Furthermore, especially for Korean construction companies, it is often the case that the failure in an international construction project cannot be offset by even a sufficient number of successful domestic achievements. Therefore, not only the selective screening among the nominated projects which have strong possibility of collapse but the systematic strategies for controlling potential risk factors are also considered indispensable in international construction portfolio management. The purpose of this study is to first analyze the causal relationships of the profit-influencing variables and the project success, and develop the profitability forecasting model in international construction projects.

• Korean Journal of Construction Engineering and Management
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• v.15 no.3
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• pp.66-73
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• 2014

The Korean construction industry has been severely impacted by the 2008 global financial crisis, which resulted in a significant reduction in the overall contract amount. For survival, many construction management (CM) companies had to adapt a strategy of lowering bid prices to maintain their competitiveness. As a result of the strategy, companies faced a number of issues including their decreased capability in risk management. However, most risk management-related studies focused on construction risk management, yet these studies lacked consideration of enterprise-level risk management practices. To fill the gap, the objectives of the present study are (1) to investigate, the risk management practices of Korean CM companies, (2) to identify factors that determine efficient enterprise-level risk management practices, and (3) to propose a module for the development of enterprise-level risk management. Lastly, the efficiency of the proposed development module was validated by using a survey.

• Korean Journal of Construction Engineering and Management
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• v.10 no.4
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• pp.14-25
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• 2009

Development work of apartment houses is a complex medium-and long-term project requiring grand resources and work force. Since in combination inner and outer project variables relate to project output, uncertainties caused by not only a given site condition but also politic, economy and social sectors are generated during the project. These risks influence output of the project as important factors, and ultimately as management variables in priority giving an effect on earnings and the financial structure of enterprises they should be manageable with the risk reduction plan. In this point of view, this study focused on development work of apartment houses among construction project. Risky factors were deduced, analyzed and evaluated based on Value Engineering from planning to designing to executing to maintaining. Eventually, this study showed the foundation guaranteeing competitive power of public and private construction sectors.

• Korean Journal of Construction Engineering and Management
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• v.6 no.3 s.25
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• pp.135-143
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• 2005

The purpose of this study is to diminish the risk through identifying the risk factors occurring in the process of real estate development projects, and analyzing and coping with the risk factors, and enable stable advance in the development process by improving the roles and work distribution of the project investor. The results of this study are as follows : 1) identifying the risks of contractions from the step of selecting the sites must be made possible through supplemental human resources expertise in plan and construction of the operation 2) as an improvement scheme, heightening the penetration wall of development projects from the investors, proposing a registration law and a selection standard of construction companies to investors' cooperating companies enabling the growth of superior investors.