• 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.

• 한국전산구조공학회논문집
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• 제22권3호
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• pp.251-258
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• 2009

개념설계단계에서 전투차량은 크게 화력성능, 기동성능과 체계의 물리적 특성으로 나누어진다. 본 연구에서는 전투차량체계를 구성하는 3가지 특성 중 화력성능의 최적화로 제한한다. 체계의 개념설계 단계에서 화력성능에 영향을 미치는 주요 인자로 파괴효과에 직접적인 영향을 주는 탄의 중량과 원거리 사격을 고려한 최대사거리를 분석대상으로 선정하였다. 최대 사거리 분석을 위하여 강내탄도와 강외탄도해석은 질량 집중 모델, Le Duc모델과 질점탄도모델을 사용하여 분석하였다. 실험계획법과 회귀분석으로 반응표면식을 구성하고 선정된 인자를 반응표면법으로 최적화하였다.

• 한국방재안전학회논문집
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• 제12권4호
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• pp.63-72
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• 2019

최근 이상기후로 집중호우 및 태풍 등과 같은 극한홍수사상의 발생으로 인한 인적 및 물적 피해가 과거와 비교하여 증가되고 있다. 이러한 피해를 예방하기 위하여 유역 수문분석이 필요하지만, 미계측 유역에서는 수문분석을 위한 수문 자료의 관측이 비교적 제한적이다. 이에 본 연구에서는 수문 자료가 제한적인 미계측 유역의 태풍사상에 의한 피해에 대비하기 위하여 개념적 강우-유출 모형의 지역화 모형을 개발하였다. 개발된 지역화 모형의 검증을 통하여 유역을 대표하는 모형 매개변수를 산정할 수 있다고 판단하였다. 향후 하천관리 및 수방시설물 설계에 기초 자료로 활용될 것으로 기대한다.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2003년도 추계학술대회 및 정기총회
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• pp.35-40
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• 2003

This paper presents a method for designing layout on the yard and evaluating alternative designs of the layout by applying simulation. The method is based on the concepts of the conventional port container terminal with a perpendicular yard layout. In general, yard design of the container terminal is consists of the two major parts. One is to divide yard area between the number of sections and the number of runs and the other is to decide the number of equipment that is the yard truck and yard crane. In the past days, this design was depended on the experience of the terminal operator and the structure of the conventional terminal layout because it is a very complex decision problem. In this paper we suggest the method of yard design as a conceptual procedure and estimate the efficiency of the container crane and the optimal the number of equipment using the simulation. Numerical examples are provided in order to illustrate the conceptual procedure. As the example, the suggested method and simulation are applied to the virtual container terminal with a perpendicular yard layout. In the results, the number of sections and runs on yard area, the number of yard truck per container crane and the number of yard crane per run are decided. In additional, the traffic among blocks on yard layout is estimated in terms of rate.

• 한국건설관리학회논문집
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• 제15권2호
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• pp.53-61
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• 2014

건설 프로젝트는 생산과정 이전에 설계도면을 바탕으로 예상되는 비용이 산정되며, 기획단계는 소요예산을 책정하고 설계단계는 예산에 합당한 효율적 대안을 찾으며, 정확한 입찰금액을 예측하기 위해 수차례 이루어진다. 특히, 물량산출 이전까지 예측되는 공사비의 정확도와 신뢰도는 매우 중요하다. 그러나 국내의 경우 면적당 단가 방식 공사비 예측을 벗어나지 못할 뿐 아니라, 단계별 예측방법, 프로세스, 데이터 분석 및 관리기술 등이 표준화되어 체계적이고 종합적으로 관리되지 못하고 있다. 그리고 복합용도 프로젝트에서의 견적은 그 사례도 적고 단가정보를 얻기가 매우 어렵다. 이에 국내 복합용도 프로젝트 공사비 예측기술 및 관리기술 발전을 위하여 BIM의 공간정보를 활용한 내부마감 개략견적 코스트 모델을 개발하여 제시하였다.

• Nuclear Engineering and Technology
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• 제41권10호
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• pp.1347-1360
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• 2009

A multi-dimensional component for the thermal-hydraulic system analysis code, MARS, was developed for a more realistic three-dimensional analysis of nuclear systems. A three-dimensional and two-fluid model for a two-phase flow in Cartesian and cylindrical coordinates was employed. The governing equations and physical constitutive relationships were extended from those of a one-dimensional version. The numerical solution method adopted a semi-implicit and finite-difference method based on a staggered-grid mesh and a donor-cell scheme. The relevant length scale was very coarse compared to commercial computational fluid dynamics tools. Thus a simple Prandtl's mixing length turbulence model was applied to interpret the turbulent induced momentum and energy diffusivity. Non drag interfacial forces were not considered as in the general nuclear system codes. Several conceptual cases with analytic solutions were chosen and analyzed to assess the fundamental terms. RPI air-water and UPTF 7 tests were simulated and compared to the experimental data. The simulation results for the RPI air-water two-phase flow experiment showed good agreement with the measured void fraction. The simulation results for the UPTF downcomer test 7 were compared to the experiment data and the results from other multi-dimensional system codes for the ECC delivery flow.

• 한국재난정보학회 논문집
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• 제3권2호
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• pp.39-53
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• 2007

In modern society, the natural disaster damage is increasing by unusual weather conditions such as global warming. Many disaster victims in the disaster spot suffered from the heavy damages. In these conditions, this paper aims to improve of relief system in disaster. To achieve our aims, we analyzed the present disaster relief system in a legal, institutional aspect and disaster relief on the conceptual content, and look at the contents of the damage I have seen. And we are look at the issue of disaster relief, disaster relief measures to improve the present. In conclusion, this research suggests the improvements of the disaster relief system. First, Donations to secure transparency of the scheme passes. Second, the reality of actual expenses paid farmland. Third, recovery estimate by the reality. Fourth, when the disaster occurred, and the disaster of the itemized information. Finally, the degree of damage to the housing relief material support systems need improvement.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제16권2호
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• pp.111-118
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• 2016

Artificial intelligence (AI) is making computer systems intelligent to do right thing. The AI is used today in a variety of fields, such as journalism, medical, industry as well as entertainment. The impact of AI is becoming larger day after day. In general, the AI system has to lead the optimal decision under uncertainty. But it is difficult for the AI system can derive the best conclusion. In addition, we have a trouble to represent the intelligent capacity of AI in numeric values. Statistics has the ability to quantify the uncertainty by two approaches of frequentist and Bayesian. So in this paper, we propose a methodology of the connection between statistics and AI efficiently. We compute a fixed value for estimating the population parameter using the frequentist learning. Also we find a probability distribution to estimate the parameter of conceptual population using Bayesian learning. To show how our proposed research could be applied to practical domain, we collect the patent big data related to Apple company, and we make the AI more intelligent to understand Apple's technology.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.134-137
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• 1999

It is certain that the power quality will be very important at 21 century. Especially instant power shortage or power fault will occur serious problems. Accordingly stable power supplication is very technical problem. There are many way to make stable supplication as auxiliary generator, but this is long time delay complement. To solve this problem the superconducting magnetic energy storage is introduced. High Tc superconductor is more commercial.

• 한국주거학회논문집
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• 제17권1호
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• pp.107-115
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• 2006

It is the purpose of this study that propose method to estimate weights of decision-making for design concepts considering characteristics of places. In order to acquire these weights of concepts, the investigation with questionnaire by AHP(Analytic Hierarchy Process) is employed as a mean. Targets of this investigation was 63 respondents which were graduate students(21) and experts of design field(42). As a result, we could find differences between these weights of the relative concepts and know the differences in the weights of design concepts as characteristics of places were reflected. These weights of concepts will be take opinions about concept from design-related members into consideration. Therefore, In design process, the weights of design concepts will help for designer to verify the concepts in design initially, and finally be used by a criteria in decision-making. The Weights of decision-making for design concepts as a result of this study will be used as a guideline for the systematical and conceptual approach in design practice.