• 대한교통학회지
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• 제12권3호
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• pp.5-13
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• 1994

In the fields of rail and road design, most vertical alignment design have been thus far heavily dependent upon trial-and-errors of experienced engineers. However, it has long been inefficient in productivity of designing process. In order to overcome this inefficiency, this paper presents the optimal vertical alignment design method using mathematical optimization techniques. For optimization, mathematical model to minimize the construction cost is formulated and the separable programming technique and the Zoutendijk method are introduced to solve it. As result, it is shown that this optimization technique can give efficient solutions to all vertical alignment design fields with properly-estimated cost function.

• 품질경영학회지
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• 제18권1호
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• pp.77-83
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• 1990

A model for the economic design of an pn control charts with an assignale cause is presented and the loss-cost function for control schemes using these charts is derived. By minimizing this function with respect to the three control variables, namely, the sample size, the sampling interval and acceptance number, the economically optimal control plan can be optained. The article shows what influence increasing or decreasing condition, according to changeability of the size of these factors, of expected cost can have on the economy when an attribute control chart is used.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• 제1호
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• pp.213-218
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• 2001

To many developing countries like China, the practical way to constant development of city construction is low consuming. The basic methods of low-cunsuming landscape construction: 1) Low building consumption: Decreasing construction quantity. Using low-costing material. Designing low-consuming landscape. Reusing of building material. 2) Low energy consumption: Decreasing water consumption. Consuming and enrichment of earth fertilizer. Decreasing electrical consumption. 3) Low maintenance: Adapting natural material. Using local plants. Special design to decrease maintaining. Because of many reasons, China has not yet adapting Low-consuming Landscape Construction.

• 대한토목학회논문집
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• 제28권5D호
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• pp.665-675
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• 2008

본 연구는 터널공사를 대상으로 사업 초기단계에서 터널공사의 설계 대안에 대한 공사비를 신속히 추정하고, 사업이 진행되면서 상황변화에 따른 사업비 측면에서의 영향을 파악할 수 있도록 함으로써, 적정한 의사결정을 지원하기 위한 개략적 터널공사비 추정모델 제시를 목적으로 한다. 이를 위해 터널공사의 수행에 있어 공사비에 영향을 미치는 요인을 분석하고, 공사비 영향요인별 공사비 변화의 정도를 분석하였다. 공사비 영향요인은 천공방식, 굴착방법, 기폭장치, 적재장비 용량, 버력의 단위중량 및 토량환산계수, 터널 연장을 포함하는 7개의 요인을 대상으로 하여 각 영향요인의 변화에 따른 공사비 변동 크기를 분석하였다. 분석결과는 기획단계에서 사업의 기본적인 조건을 바탕으로 사업비를 추정하고, 설계 및 시공단계에서 설계 대안에 대한 공사비의 영향을 효율적으로 평가하는데 필요한 공사비 추정모델의 구축을 위한 기초정보를 제공할 것으로 기대된다.

• 한국건축시공학회지
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• 제5권1호
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• pp.97-103
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• 2005

Building costs means capital costs which include cost of land, costs of acquiring and preparing the site, construction costs, professional fees, furnishings, cost of financing the project. and cost of management required to run and maintenance the building for use. There are several phases that determine the building costs : design phase, construction phase, and operation & maintenance phase. So, the cost of work could be set against the examining the full range of complexities that a building program might contain. To solve this problem, it needs to compute building cost systematically. This is still in the development stage, awaiting the organization of rational cost data base. The method of cost saving by cost control could be constituted by detailed knowledge of building costs for all possible combinations of components and subsystems that can be assembled into integration model of cost factor on each phase of project development. The model of cost saving in each building phase is available for procedures of cost control of building systems.

• 에너지공학
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• 제23권4호
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• pp.236-239
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• 2014

한수원 중앙연구원은 2007년부터 정부과제의 하나로 전기출력이 1500MWe급인 GEN.III+ 원전 APR+를 개발하고 있다. APR1400에 비해 보다 개선된 안전성과 경제성을 갖는 원전을 개발하기 위해 국내 건설 중인 원전과 해외에서 개발 또는 건설 중인 ALWR(Advanced Light Water Reactor)의 설계내용 및 후쿠시마 원전사고로부터 도출된 개선사항을 반영하여 한국 실정에도 맞고, 해외 수출형 원전에도 부합되는 원전을 설계하고 있다. APR+의 경쟁력을 확인하기 위해 APR+ 표준설계개발 단계에서 3회의 경제성 평가를 수행하였다. 표준설계개발 단계에의 3차(최종) 경제성 평가 결과 APR+ N-th호기는 국내석탄화력 1000MWe급 대비 약 23% 경쟁력 우위인 것으로 평가되었다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 춘계학술대회 논문집
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• pp.387-393
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• 2001

Installing vibration control devices in the structure rises as a solution instead of increasing structural strength considering construction cost. Especially, viscoelastic dampers show excellent vibration control performance at low cost and are easy to install in existing structures compared with other control devices. Therefore, cost-effectiveness of structure with viscoelastic dampers needs to be evaluated. Previous cost-effectiveness evaluation method for the seismically isolated structure(Koh et al., 1999;2000)is applied on the building structure with viscoelastic dampers, which combines optimal design and cost-effectiveness evaluation for seismically isolated structures based on minimum life-cycle cost concept. Input ground motion is modeled in the form of spectral density function to take into account acceleration and site coefficients. Damping of the viscoelastic damper is considered by modal strain energy method. Stiffness of shear building and shear area of viscoelastic damper are adopted as design variables for optimization. For the estimation of failure probability, transfer function of the structure with viscoelastic damper for spectral analysis is derived from the equation of motion. Results reveal that cost-effectiveness of the structure with viscoelastic dampers is relatively high in how seismic region and stiff soil condition.

• 한국BIM학회 논문집
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• 제7권2호
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• pp.16-24
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• 2017

It is very important to estimate accurate construction total cost needed early in the project. In the initial phase of the design, the project cost estimates are determined by total quantity from design documents and the variables that affect the calculation of the total cost of the project. In order to determine accurate total construction cost, the contractor has to produce detailed quantity information based on the drawings and specifications. The process of preparing quantification and cost estimation documents is still being worked out manually, and a lot of errors have been occurred in many cases. Recent advances in information technology have led to the BIM based quantity takeoff and cost estimation. However, there are some limits to the extent to which the current specifications for BoQ documents are computed from BIM model. This research analyze the current BoQ cases and analyze how to make quantity takeoff possible through BIM. The study defined five levels of quantity category that could be produced by BIM. Only about 40% or indirectly usable items can be used when information is extracted to BIM modelling. This is very insufficient to fill out the BoQ. The BoQ document structure quantity takeoff specifications should be simplified in order to BIM based cost estimation more efficiently.

• Structural Engineering and Mechanics
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• 제43권1호
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• pp.31-51
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• 2012

This paper presents a computational study that explores the design of rigid steel frames by considering construction related costs. More specifically, two different aspects are investigated in this study focusing on the effects of (a) reducing the number of labor intensive rigid connections within a frame of given geometric layout, and (b) reducing the number of different member section types used in the frame. A genetic algorithm based optimization framework searches design space for these objectives. Unlike some studies that express connection cost as a factor of the entire frame weight, here connections and their associated cost factors are explicitly represented at the member level to evaluate the cost of connections associated with each beam. In addition, because variety in member section types can drive up construction related costs, its effects are evaluated implicitly by generating curves that show the trade off between cost and different numbers of section types used within the frame. Our results show that designs in which all connections are considered to be rigid can be excessively conservative: rigid connections can often be eliminated without any appreciable increase in frame weight, resulting in a reduction in overall cost. Eliminating additional rigid connections leads to further reductions in cost, even as frame weight increases, up to a certain point. These complex relationships between overall cost, rigid connections, and member section types are presented for a representative five-story steel frame.

• 대한간호학회지
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• 제49권5호
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• pp.586-600
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• 2019

Purpose: This study aimed to develop a web-based cost management program for visiting nursing centers (CMP-VNC), using time-driven activity-based costing (TD-ABC), and to analyze effects of the program. Methods: The CMP-VNC was developed using the combined prototyping approach and system developing life cycle method following four stages: need analysis with comprehensive literature reviews and focus group interviews, design and development of program algorithm, evaluation of the developed program validity using experts and users group, and application and effects analysis. The non-equivalent control group pretest-posttest design was used to analyze the effects of the program. The program demonstration was conducted for four weeks with 60 visiting nurses in 35 visiting centers. Results: The web-based program was developed. It has five interfaces with basic and special functions using TD-ABC, namely, input, visiting nursing activity, visiting nursing activity cost, cost efficiency, and cost calculation report. The experimental group showed significantly higher cost perception and cost confidence than control group. Conclusion: We found that the CMP-VNC can be an effective tool to increase visiting nurses' competency of costing and enhance efficiencies of visiting nursing centers.