• 한국도로학회논문집
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• 제19권5호
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• pp.153-162
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• 2017

PURPOSES : This study was conducted to analyze the effects arising from extending the duration of nighttime road construction on improving road quality and durability. METHODS : Most previous studies estimating the social cost of various construction conditions did not consider road pavement cooling time as a factor in improving road pavement quality. This study investigated the feasibility of achieving higher road quality and durability by extending the duration of nighttime road construction time extension. For this investigation, the effects of such an extension on traffic conditions were analyzed based on micro-simulation studies and scenario-based cost-benefit analyses, using factors including traffic volume, delay, construction cost, and road pavement cooling time. RESULTS : The results of the traffic simulation studies and cost-benefit analyses indicate that the current road construction method that emphasizes completing nighttime road construction by 6 a.m. reduces pavement life while causing relatively little traffic delay. If the night construction time is instead extended to 2 p.m., road pavement lifetime is increased, reducing road re-construction cost. These savings are greater than the cost of congestion arising from extending the duration of nighttime construction. CONCLUSIONS : The current nighttime construction durations need to be extended in order to efficiently manage roads and reduce road management costs.

• 한국건축시공학회지
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• 제12권6호
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• pp.636-647
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• 2012

Construction projects have become so large, complicated and incredibly high-tech that process management is currently considered one of the most important issues. Unlike typical manufacturing industries, most major construction activities are performed in the open air and thus are exposed to various environmental factors. Many studies have been conducted with the goal of establishing efficient techniques and tools for overcoming these limitations. Productivity analysis and prediction, one of the related research subjects, must be considered when evaluating approaches to reducing construction duration and costs. The aim of this research is to present a quantified impact analysis of construction delay factors on construction productivity of a steel staircase system, which has been widely applied to high rise building construction. It is also expected to improve the process by managing the factors, ultimately achieving an improvement in construction productivity. To achieve the research objectives, this paper analyzed different delay factors affecting construction duration by means of multiple regression analysis focusing on steel staircase systems, which have critical effects on the preceding and subsequent processes in structure construction. Statistical analysis on the multiple linear regression model indicated that the environment, labor and material delay factors were statistically significant, with 0.293, 0.491, and 0.203 as the respective quantified impacts on productivity.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.608-615
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• 2022

Construction projects are large-scale projects that require extensive construction costs and resources. Especially, scheduling is considered as one of the essential issues for project success. However, the schedule and resource management are challenging to conduct in high-tech construction projects including complex design of MEP and architectural finishing which has to be constructed within a limited workspace and duration. In order to deal with such a problem, this study suggests resource and sequence optimization using constraint programming in construction projects. The optimization model consists of two modules. The first module is the data structure of the schedule model, which consists of parameters for optimization such as labor, task, workspace, and the work interference rate. The second module is the optimization module, which is for optimizing resources and sequences based on Constraint Programming (CP) methodology. For model validation, actual data of plumbing works were collected from a construction project using a five-minute rate (FMR) method. By comparing actual data and optimized results, this study shows the possibility of reducing the duration of plumbing works in construction projects. This study shows decreased overall project duration by eliminating work interference by optimizing resources and sequences within limited workspaces.

• 한국건축시공학회지
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• 제14권6호
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• pp.591-596
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• 2014

본 연구는 현재 사회적 문제가 되고 있는 도시재생 사업의 매몰비용 관련 인식 조사를 목적으로 실시하였다. 조사결과 지방정부, 중앙정부, 정치권, 조합원 및 토지 등 소유자 모두 매몰비용에 관하여 일정부분 책임과 부담 의무의 필요성이 있는 것으로 나타났다. 매몰비용에 대한 지원은 어느 하나의 주체에게 책임을 전가하기보다 정비 사업에 참여했던 주체 모두가 함께 책임을 통감하여 문제가 되고 있는 매몰비용의 부담과 해결 방안까지 공유해야하는 것으로 나타났다. 공공은 매몰비용에 대해 직접적인 지원보다는 간접적 지원(기반시설 부담, 세제혜택, 규제기준 완화 등)을 통하여 조합 등이 사업 추진의 지속 여부에 대하여 합리적인 선택을 할 수 있도록 유도하여야 하여야 할 것이다.

• 한국농공학회논문집
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• 제50권4호
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• pp.51-58
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• 2008

Unit costs for energy production in bioenergy facilities are dependent upon both fixed cost for facility construction and operational costs including biomass feedstock supply. With the increase of capacity, unit fixed cost could be decreased while supply cost tends to increase due to the longer transportation distance. It is desirable to take into account biomass availability in planning bioenergy facilities. A cumulative curve relationship was proposed to relate biomass availability and cumulative products of biomass amount and transportation distance. Optimum size of gasification facilities was affected by collection cost, biomass cumulative relationship. Based on biomass availability of Icheon-City, optimum sizes were about $400kW_{th}$ for gas production, and about $200kW_{el}$ for power generation. Unit cost of bioenergy production could be substantially reduced by reducing collection cost through supplying biomass from diverse sources including land development areas where significant amount of waste wood is generated. When planning bioenergy facilities, however, biomass availability and spatial distribution are key factors in determining the size of capacity.

• Computers and Concrete
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• 제25권2호
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• pp.111-118
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• 2020

The construction field must always explore sustainable ways of using its raw materials. Studying the environmental impact generated by reinforced concrete raw materials during their production and transportation can contribute to reducing this impact. This paper initially presents the carbon dioxide emissions from reinforced concrete raw materials, quantified per kilo of raw material and per cubic meter of concrete with different characteristic strengths, for southern Brazil. Subsequently, reinforced concrete elements were optimized to minimize their environmental impact and cost. It was observed that lower values of carbon dioxide emissions and cost savings are generated for less resistant concrete when the structural element is a beam, and that reductions in the cross section dimensions of the beams, sized based on the use of higher strength concrete, may not compensate for the increased environmental impact and costs. For the columns, the behavior differed, presenting lower values of carbon dioxide emissions and costs for higher concrete strengths. The proposed methodology, as well as the results obtained, can be used to support structural projects that have less impact on the environment.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2017년도 학술발표회
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• pp.218-218
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• 2017

Urbanization increases impervious area and decreases the water quantity infiltrating into soil layers. This leads to lack of ground water, it could be possibly problematic for agricultural water for crop growth in lower basins, reducing not only ground water but also streamflow quantities. One such approach to minimize the impact of urbanization is to apply low impact developments (LIDs). LIDs are to decrease the percentage of impervious area so that infiltration rate is increased, there is a need to simulate the LIDs prior to the construction. LIDs in Storm Water Management Model (SWMM) are limited to be seven types, however it is often required to simulate LIDs more than seven types. Therefore an approach to apply eleven LIDs is provided in the study, updating the model parameters. A scenario containing eleven LIDs was given by the environmental decision makers, the effect of LIDs were simulated with the expected annual costs considering establishment and maintenance costs.

• 한국도로학회논문집
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• 제15권2호
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• pp.149-157
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• 2013

PURPOSES : This study is to analysis for benefit and construction cost in underpass for small vehicles. METHODS : The study was performed using the traffic software VISSIM 5.20 for analysis on a variety of traffic conditions and analysed of benefits of changes through analysis of travel speed and travel time after modeling of existing underpass and small vehicle underpass. RESULTS : Results of this study, the benefits will be reduced by the introduction underpass for small vehicles were analyzed because heavy vehicles use the intersection above the underpass. However, it was required economic analysis considering both the benefits reduction and the construction costs reduction because it has the effect of reducing the construction cost. Showed that the difference in benefit changes depending on the v/c and heavy vehicles ratio and construction cost was difference by types of underpass. As a result of performing economic analysis with total benefits and construction cost, it was analyzed to be economical in underpass over a certain size. CONCLUSIONS : The result of this study are expected to be able to contribute to reviewing for feasibility due to the small vehicles underpass introduction and economic analysis. The study is case study to the underpass in Daegu. Therefore, the future requires the calculation of benefits reflect a wider range of traffic conditions and the economic analysis to construction cost calculation for various types of grad separation facilities.

• 대한안전경영과학회지
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• 제19권1호
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• pp.53-62
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• 2017

Full embroidery industrial accidents in recent years has shown a declining trend. But disaster embroidery of domestic construction industry were more than 20,000 deaths per year is about 500 people. The government has introduced a construction site often changing the recruitment of new construction based on health and safety as an alternative to road safety education training yisuje of construction workers, daily work periods short. Certificate of Basic OSH Training in Constructions had also been evaluated as successful by reducing the accident rate problem. It is conducted in private educational institutions has occurred on the friction between workers and employers and training costs are difficult to approach workers in the education standards for such facilities due to the superintendent. Educational institutions are institutions that have been caused by excessive competition lowered levels of education. There is also a lack of evaluation that the training is limited to the basic safety knowledge. These details are brought formal safety education purposes only and is introducing the results of other self jyeotgi difficult to reap the proceeds to good effect. In this study, we propose a plan for improving operational problems and enemy status based on research data presented after the Certificate of Basic OSH Training in Construction.

• 설비공학논문집
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• 제24권1호
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• pp.70-76
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• 2012

The purpose of this study is to analyze of the operating characteristics of the Gas engine driven Heat Pump(GHP) and to reduce maintenance costs through the most Economical plan. As the zoning modifications that have economic effects were confirmed. Applications should be made with a similar purpose of the space. The combination of a modified space has led to reduced operating hours of the outdoor unit. The reduction of the outdoor unit operating hours, reducing maintenance costs accordingly. When analyzed at six years have elapsed, the amount of savings through zoning modifications is more than an additional construction cost. During the design phase, cost-effective operation of the GHP is required for the proper zoning plan.