• 국제학술발표논문집
• /
• The 2th International Conference on Construction Engineering and Project Management
• /
• pp.69-78
• /
• 2007

In real world, the project managers handle conflicting goals that govern the use of resources within the stipulated time and budget with required quality and safety. These conflicting goals are required to be optimized simultaneously by the project managers in the framework of fuzzy aspiration levels. The fuzzy linear programming model proposed herein helps project managers to minimize total project costs, completion time, and crashing costs considering indirect costs, contractual penalty costs etc by practically charging them in terms of direct cost of the project. A case study of bituminous pavement under construction is considered to demonstrate the feasibility of applying the proposed model for optimization of project parameters. Consequently, the proposed model yields an efficient compromise solution and the decision maker's overall degree of satisfaction with multiple fuzzy goal values. Additionally, the proposed model provides a systematic decision-making framework, enabling decision maker to interactively modify the fuzzy data and model parameters until a satisfactory solution is obtained. The significant characteristics that differentiate the proposed model with other models include, flexible decision-making process, multiple objective functions, and wide-ranging decision information.

• 한국건설관리학회:학술대회논문집
• /
• 한국건설관리학회 2003년도 학술대회지
• /
• pp.485-490
• /
• 2003

최근 대내외적인 건설환경의 급격한 변화와 건설공사의 대형화${\cdot}$복잡화 추세는 내외부적으로 많은 리스크 요인을 증대시키고 있기 때문에, 이에 대한 합리적이고 효율적인 관리방안의 중요성이 크게 대두되고 있다. 본 연구에서는 이러한 리스크 관리방안의 하나로서, 사업추진과정에서의 공사비 증액이 매우 제한되어 있어 입찰단계에서 견적금액의 불확실성 요소(예비비)를 고려해야만 하는 턴키공사 등 대형 건설공사를 대상으로, 이에 내재된 리스크요인의 정량화를 통해 합리적이고 적절한 예비비를 산정할 수 있는 모델을 제시하고자 한다. 예비비 산정모델의 개발을 위하여 실제 수행된 프로젝트를 선정하여 각 공사의 예비비 집행현황, 공사비 현황 등의 자료를 토대로 공사비에 영향을 미치는 인자를 도출하였으며, 몬테칼로 시뮬레이션(Monte Carlo Simulation)과 영향도(Influence Diagram), 의사결정 수형도(Decision Tree)를 혼합한 CRM(Cost Risk Model)을 적용하여 이러한 리스크 인자의 영향을 구조화하였다. 또한 구축된 모델을 기 완료된 대형공사에 적용하여 그 타당성을 검증하고자 하였다.

• 물과 미래
• /
• 제29권3호
• /
• pp.197-205
• /
• 1996

상수도 관망시설에서 각 관로는 시간이 경과함에 따라 각종 부식이 일어나 통수능이 저하된다. 그러므로 적절한 시기에 갱생이나 교체 등의 처리를 해주어야 한다. 본는 연구에서는 각 수요절점에서 요구수량, 요구압력 등 수리학적 조건을 만족시켜주며 동시에 최소의 비용으로 노구된 관로를 처리해주는 의사결정모형을 개발하였다. 교체비용, 관파열보수비용, 양수비용, 관 파열율, 연이율 등은 각 관로의 교체시기를 경제적으로 결정하는데 이용된다. 그리고 배수시설의 수리학적 만족여부는 관망계산 프로그램 KYPIPE에 의해 점검된다. 시스템이 수리학적 조건을 만족지 못할 경우 교체시기는 조건이 만족될 때까지 앞당겨진다. 본 모형은 기존 송배수시설인 수도권 광역상수도 제1단계에 적용되었다. 모형을 이용해 산출한 최적교체시키는 수리학적으로 모의해본 결과 문제가 없으며를 알 수 있었다.

• 산업공학
• /
• 제15권2호
• /
• pp.159-171
• /
• 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.

• 한국지역지리학회지
• /
• 제4권2호
• /
• pp.79-94
• /
• 1998

90년대에 들어서 국내에서는 많은 지리정보 사업이 실행되고 있다. 바로 이 시점이 지리정보 사업의 여러 가지 기술개발과 적용, 지리정보 사업의 공공 정책적 접근방법 및 연구가 필요한 시점이라고 본다. 본 연구는 공공기관에서 시행되는 지리정보 사업에 대한 정책적 중요성을 검토하고 정책 분석적 측면에서 사업은 어떻게 평가되어야 하며, 어떤 내용들이 어떠한 절차와 단계를 거쳐 검토되어야 하는가를 연구한 것이다. 이러한 정가와 분석을 위해서 '비용편익 분석'을 하나의 분석방법으로 제시하면서, 이 방법이 지리정보 사업을 평가하는데 어떠한 장정과 단점을 갖는지를 연구했다. 주요 이점은 자료 분석의 용이, 지도 출력 및 수정 변경의 비용 절감 등이 유형의 이점으로 볼 수 있는 반면, 저리정보의 질적 향상과 보다 정확한 지리정보의 관리 및 운영, 의사결정지원 등이 무형의 이점으로 나타났다. 그러나 이러한 이점들은 지리정보 사업 시행 이전의 비용편익 분석에서 효과적으로 분석될 수 있는 부문이 있는 반면, 무형의 이점들은 여전히 비용 편익 개념에서 제대로 파악될 수 없는 경우가 있다. 이러한 문제점들은 향후 연구 과제로써 일반적인 계량적 평가 방법과 아울러 질적인 무형의 이점까지도 평가할 수 있는 다양한 분석 방법 및 평가 수단의 계속적인 연구가 필요하다.

• Environmental Analysis Health and Toxicology
• /
• 제30권sup호
• /
• pp.6.1-6.4
• /
• 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.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 제13회 신호처리 합동 학술대회 논문집
• /
• pp.65-68
• /
• 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.

• 한국경영과학회:학술대회논문집
• /
• 한국경영과학회 2004년도 추계학술대회 및 정기총회
• /
• pp.147-157
• /
• 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
• /
• 제21권1호
• /
• pp.25-29
• /
• 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.

• 한국IT서비스학회지
• /
• 제11권4호
• /
• pp.69-85
• /
• 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.