• 한국국방경영분석학회지
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• 제25권2호
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• pp.44-61
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• 1999

Cost estimation has posed a significant challenge to estimators, planners, and managers in both government and military. Considerable historical evidence shows that accurate cost estimation has been difficult to achieve across a wide range of projects, including weapon systems. This paper introduces new cost estimating concept, CAIV(Cost As an Independent Variable) and a cost estimating case study using PRICE model, computer aided parametric estimating models(CAPE) for K1 tank cost estimate. CAIV concept is to set realistic but aggressive cost objectives easily in each acquisition program and to achieve cost, schedule, and performance objectives considering various managing risks with a project manager and industry teams. The Price model is one of computer aided cost estimating models and widely used in U.S. defense system analysis as a tool for CAIV. We analyze theories, inputs, outputs of the PRICE model and present a case study for K1 tank to estimate costs in requirement and concept phase, program and budgeting phase, and life cycle phase. Finally we obtain results that the Price model can be used in various phases of PPBEES depending upon available data and time.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1209-1215
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• 2009

Recently, Construction Projects are being much bigger and more complex. So the importance of Construction Planning and Management is increasing and increasing because of the Construction Projects is involved in a variety of construction-related subjects. Competitive of the Construction Industry decided Cost, Construction Duration and Productivity. But they were just focused on Cost Saving instead of Construction Duration and Productivity. However, they have to finish construction projects using minimum cost and duration with quality and function of required level for successful Construction projects. Thus, current high exchange rate and high period, it is clear to decrease construction cost and to do economic construction in huge Construction Projects and it means more advanced Construction Schedule Management needs for economic construction. But Construction Scheduling Planning, basic of Construction Schedule Management, adjusted contract period without Pre-Planning, just depending on experience and ability of Construction Engineer. Because of that, this study suggests new Duration Estimate Method using Stochastic Model in BIM Environment for advanced Construction Schedule Management. Existing Duration Estimate Methods are just modified wrong points of them or analyzed effective factors of construction schedule. However, New Duration Estimate Method is just consists of Stochastic Model and BIM Environment without existing Duration Estimate Methods. So, new method has creativity and specialty. After this research, it would be a great model in construction industry field.

• 한국건설관리학회논문집
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• 제7권4호
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• pp.91-99
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• 2006

본 연구는 신축 교육시설 프로젝트의 개념단계에서 공사비를 예측하기 위한 인공신경망모델의 제안을 목적으로 한다. 현행 공공 교육시설의 개념단계 공사비예측에는 기본인자인 연면적에 의한 단일변수 모델이 적용되고 있다. 그러나 개념단계에서 단일변수 공사비예측모델을 적용하여 예측된 공사비는 그 오차범위가 크고, 실시설계 완료 후 물량산출에 의해 산정된 상세공사비와 비교하여 큰 차이를 보일 경우 프로젝트의 수정이 불가피하며, 이는 프로젝트의 비용을 증가시키고 공기를 지연시킨다. 그러므로 본 연구에서는 교육시설 프로젝트의 사업계획 수립 및 예산확보 과정에서 공사비예측에 적용이 가능한다 변수 인공신경망모델을 제안하였다. 개발된 모델을 평가한 결과 평균오차율이 6.82%로써, 평균 93.18%의 정확도를 기록하였다. 제안된 인공신경망모델은 지난 5년간 신축된 교육시설의 공사예정금액을 실적자료로 사용하여 학습되었기 때문에, 차후 교육시설 신축공사의 예산편성에 그 활용이 기대된다.

• 한국구조물진단유지관리공학회 논문집
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• 제11권6호
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• pp.131-142
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• 2007

생애주기비용을 고려한 교량의 설계 및 유지관리에 있어서, 점검진단, 보수보강 등에 소요되는 직접적인 비용뿐만 아니라 간접적인 비용인 도로이용자비용은 중요한 비용항목으로 고려되고 있다. 직접비용과 비교하여 상대적으로 추정이 곤란한 도로이용자비용의 추정을 위하여 우회도로의 효과를 고려한 이용자지연비용과 차량운행비용의 정식화를 수행하고, 시간지체에 따른 도로이용자비용의 추정을 위한 회귀모델 개발을 위하여 교통해석과 회귀분석을 수행하였다. 개발된 회귀모델을 생애주기 비용 및 성능 기반 유지관리 전략 수립에 적용하여 도로이용자비용이 생애주기분석에 미치는 영향을 분석하고, 개발된 모델의 적용성에 대해서 고찰하였다. 도로이용자비용은 생애주기분석에 기초한 유지관리전략수립에 큰 영향을 미치며, 개발된 회귀모델은 교량의 도로이용자비용의 추정에 실용적으로 활용될 수 있을 것으로 판단된다.

• 한국건축시공학회지
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• 제6권3호
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• pp.115-122
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• 2006

This study is aimed to get clear model for CM fee level in public construction project. For the practical use and main target, CM for fee contract only is assessed and analysed. Cost estimate by percentage of total contract sum and method based on the historical construction data have significant deficiency. An regression model and probabilistic model are suggested with 9 independent variables. In the case of limited work scope, an element based floor area model is suggested and concluded with fish-bone scheme.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.488-493
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• 2013

Accurate initial cost estimates are essential to effective management of construction projects where many decisions are made in the course of project management by referencing the estimates. In practice, the initial estimates are frequently derived from historical actual cost data, for which standard distribution-based techniques are widely applied in the construction industry to account for risk associated with the estimates. This approach assumes the same probability distribution of estimate errors for any selected estimates. This assumption, however, is not always satisfied. In order to account for the probabilistic nature of estimate errors, an alternative method for measuring the risk associated with a selected initial estimate is developed by applying the Bayesian probability approach. An application example include demonstrates how the method is implemented. A hypothesis test is conducted to reveal the robustness of the Bayesian probability model. The method is envisioned to effectively complement cost estimating methods that are currently in use by providing benefits as follows: (1) it effectively accounts for the probabilistic nature of errors in estimates; (2) it is easy to implement by using historical estimates and actual costs that are readily available in most construction companies; and (3) it minimizes subjective judgment by using quantitative data only.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.935-940
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• 2005

This paper presents the results of a statistical analysis using historical data of cost contingency. As a result, a model that predicts and estimates an accurate cost contingency value using the least squares estimation method was developed. Data such as original contract amounts, estimated contingency amounts set by maximum funding limits, and actual contingency amounts, were collected and used for model development. The more effective prediction model was selected from the two developed models based on its prediction capability. The model would help guide project managers making financial decisions when the determination of the cost contingency amounts for multiple projects is necessary.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.417-424
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• 2009

For a construction project to progress smoothly, effective cost estimation is vital, particularly in the conceptual and schematic design stages. In these early phases, despite the fact that initial estimates are highly sensitive to changes in project scope, owners require accurate forecasts which reflect their supplying information. Thus, cost estimators need effective estimation strategies. Practically, parametric cost estimates are the most commonly used method in these initial phases, which utilizes historical cost data (Karshenas 1984, Kirkham 2007). Hence, compilation of historical data regarding appropriate cost variance governing parameters is a prime requirement. However, precedent practice of data mining (data preprocessing) for denoising internal errors or abnormal values is needed before compilation. As an effort to deal with this issue, this research proposed a statistical methodology for data preprocessing and verified that data preprocessing has a positive impact on the enhancement of estimate accuracy and stability. Moreover, Statistically Preprocessed data Based Parametric (SPBP) cost models are developed based on multiple regression equations and verified their effectiveness compared with conventional cost models.

• 정보처리학회논문지D
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• 제10D권7호
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• pp.1137-1144
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• 2003

소프트웨어 규모를 측정하기 위한 기존의 기능점수 기법은 관리정보 시스템에 적합하도록 구성되어 있으나 최근의 실시간 및 내장형 시스템의 적용성 확장에 따라 완전기능점수(FFP, Full Function Point) 기법이 제안되었다. 그러나, FFP 기반의 소프트웨어 규모 측정 방법에 관한 많은 연구는 이루어지고 있으나, FFP로 측정된 소프트웨어 규모에 대한 개발비용을 추정할 수 있는 모델 연구는 미흡한 실정이다. 본 논문은 FFP로 실제 개발된 소프트웨어의 완전기능점수를 기반으로 소프트웨어 개발에 투입될 노력을 추정하는 선형 회귀분석 모델과 거듭제곱 회귀분석 모델을 평가하여 가장 적합한 모델로써 거듭제곱 모델을 선정하였다. 선정된 거듭제곱 모델을 적용할 경우 가장 근사치의 소프트웨어 개발비용을 추정할 수 있음을 보였다.

• 한국재난정보학회 논문집
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• 제9권1호
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• pp.11-21
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• 2013

본 연구는 2004년 이후 도입된 실적 공사비 제도에 의하여 착공된 지하철 건설공사를 대상으로 실적공사비, 공사규모 그리고 시간을 고려하여 공사비를 예측하는 식을 제시하였다. 11개의 지하철공사 자료를 이용하여 지하철 공사비 예측을 위한 비용-규모 지수 n(신뢰범위:0.5~0.7)을 구한 결과, 총공사비 0.713, 순공사비 0.77로 도출되었다. 본 연구에서 제시한 공사비 예측 식 모델은 향후 지하철 공사 적용 현장의 사업기획, 예비조사, 타당성조사, 기본설계 단계에서 개산 공사비를 추정하는데 효과적으로 적용할 수 있을 것이다.