• Journal of the Korea Society for Simulation
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• v.27 no.1
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• pp.1-13
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• 2018

Earthwork planning is one of the critical issues in a construction process management. For the construction process management, there are some different approaches such as optimizing construction with either mathematical methodologies or heuristics with simulations. This paper propose a simulated earthwork scenario and an optimal path for the simulation using a reinforcement learning. For reinforcement learning, we use two different Markov decision process, or MDP, formulations with interacting excavator agent and truck agent, sequenced learning, and independent learning. The simulation result shows that two different formulations can reach the optimal planning for a simulated earthwork scenario. This planning could be a basis for an automatic construction management.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.1
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• pp.113-122
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• 1985

Although PERT/CPM has been used for over twenty years as a technique for scheduling in a variety of industries and various extention to the basic model have been improved the realism of considering resource constraints, none of these techniqueis have integrated resource acquistion load times and inventory records into scheduling technique. This paper is to designed to over-come basic shortcoming of previous CPM into incorperate with MRP technique.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.661-670
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• 2006

The utilization of simulation has been limited in planning construction process because it is difficult to collect data and build a model using simulation method. This study collects construction operation data and analyzes the characteristics of its distribution. Through the statistical analysis on the empirical data, this study identifies Beta distribution functions is one of the most proper in duplicating the characteristics of construction equipment operation data into a computer simulation. The information obtained in this study can support preparing input data for another simulation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1D
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• pp.83-91
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• 2008

This study establishes the model to estimate a work time and a machine equipment combination in a NATM tunnel. Also it includes the increasing rate of haulage distance in the model for to make near to reality model. A simulation model focuses on the mucking process which affects the work effectiveness very highly to plan of machine use in tunneling operation. With the analysis of work effectiveness through tunnel simulation model, it is defined the problem of planning phase. Also it shows the optimal working time and efficiency of machine used through change the number of dump truck and haulage distance.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.347-353
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• 2008

Generally speaking, it is important to know the activities itself exactly and to control the activities correctly so as to assure timely progress and the quality of any project. In order to progress smoothly in accordance with construction schedule, it is important to systematize the preliminary arrangements necessary for each process and then manage them. In this study, in order to progress smoothly the quality and schedule management of the construction, we can be made systematically pre-works in accordance with construction schedule by the civil construction items of the apartment house construction. we suggested pre-construction control item by the workers through experiential method of construction engineers in accordance with network schedule.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.243-243
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• 2020

본 연구는 장래 유입수질 변화로 해수담수화(Desalination) 역삼투압(Seawater Reverse Osmosis) 공정의 전력비 예측 모델을 개발하고 별도의 해수담수화 추가공정이 필요한지 검토하였다. 플랜트 시설은 한번 설치되면 오랜 기간 운영이 되고, 주요 공정의 시설물 변경이 어려우며, 특히 해수담수화 시설의 경우에는 생활용수 및 공업용수를 수요자에 상시 공급함으로서 중간에 추가 시설물을 증설하거나 변경하기가 쉽지 않다. 따라서 해수담수화 시설의 계획 초기부터 현재의 유입수질 및 장래의 수질 변화를 예측하여 해수담수화 공정을 계획하는 것이 필요하다. 금회 검토는 해수온도 및 염분도 변화를 고려하여 서해에 위치한 대산산업단지 해수담수화 시설의 해수담수화 공정 전력비를 예측하였고, 입력 자료(온도 및 염분도)는 국가해양환경정보통합시스템(MEIS, Marine Environment Information System) 22년 과거자료(1997~2018년)를 이용하였다. 개발된 모형에 적용하여, 해수담수화에 필요한 전력비의 변화를 예측할 수 있으며, 이를 바탕으로 해수담수화 시설물 공정계획을 검토할 수 있었다. 금회 연구에서는 장래 수질변화 예측모형의 결과를 기반으로 해수담수화 시설물 공정을 제시하였다는데 의의가 있다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3D
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• pp.451-456
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• 2011

There is a relationship between effective time management and project success. Therefore, advanced time management techniques have recently been introduced. This paper investigates the current time management practices for road construction sites and proposes lean construction practices to effectively implement time management. This would be helpful to establish an effective schedule plan. Also, an efficient construction site time management system can be developed base on this fundamental research. Furthermore, future research should be performed to investigate the performance of lean construction.

• Korean Journal of Construction Engineering and Management
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• v.15 no.2
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• pp.3-11
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• 2014

As the recent construction projects have been carried out as a mixed-use complex project that includes architecture, civil, mechanical, electrical, and landscape, as well as become bigger and high-rise with the increased repetitive works, the TACT technique has received more attention as an effective method for achieving a target completion date by securing the continuous works. Although the TACT technique can maintain a steady flow without the interruption of works in order to utilize the resources of the repetitive works, it can not be considered as the systematic scheduling technique because the schedule computations are not possible as well as a critical path can not be recognized. This paper proposes the applicabilities of scheduling and monitoring the TACT schedule by the BDM technique as comparing and analyzing the methodologies for apartment finish works by the Excel, the Primavera(P6) based on the PDM technique, and the Beeliner based on the BDM technique that is a new networking technique, respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2509-2518
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• 2013

Augmented reality (AR) technology visualizes a real type object that cannot simulate in virtual reality technology by overlapping a virtual object and real object in a computer system. This study suggests a methodology and prototype system for applying AR system to rebar distribution work in a civil engineering project. Rebar work in civil engineering project is a representative activity that is progressed by empirical approach of skilled labor rather than formalized manual. AR technology improves the constructability of rebar work because AR tool can identify missing rebars and different rebars comparing with the drawings. AR system developed in this study can enhance the understanding of rebar work using 3D modeling with real image of construction site and save construction cost by reducing reconstruction work.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5D
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• pp.655-664
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• 2008

Lean Construction recommends implementing site production management by measuring the reliability of daily production tasks, collecting the causes for failure of incomplete tasks, and identifying problems in the existing process based on the collected data. Although many research projects have been performed to introduce Lean Construction in Korea, there are not many cases in which day-to-day site production operations has been stringently evaluated based on such methods. This paper introduces three cases in which such techniques were implemented on a residential, civil infrastructure and plant project. On each project, process maps were created with the superintendents and daily production meetings were held for two weeks. Consequently, the average PPC for the three projects was 79% for PPC and 16% for PAT. In addition, the majority of the failures were due to 'Directive/Plan' and 'Prerequisites.' The results show that project stakeholders (owners, contractors, etc.) lack the ability to plan ahead and keep to their plans, and also lack the capability to synchronize workflow between themselves. The results also reveal that project participants need to be more proactive in solving process problems on site and also need to be better educated in Lean concepts and methodologies.