• Korean Journal of Construction Engineering and Management
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• v.14 no.2
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• pp.141-149
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• 2013

This paper presents a scheduling technique that reflects various constraints in remodeling project of inhabited condition. The remodeling project of inhabited condition is required more detailed planning and control due to claims by noise, vibration, dust, smells, limited lift capacity, and limited temporary stock area. Because of the constraints, complexity in scheduling is increased and earlier completion is required to reduce the possibility of safety and environment accidents. Especially, in case of inhabited condition, the scheduling should be linked day-time/night-time/weekend work. This paper proposes a structured scheduling technique to incorporate those constraints in remodeling of inhabited condition. This scheduling technique considers not only remodeling process but also dismantling, newly-construction, and residents movement. Process expression method using MS-Project also presented to keep connectivity with existing scheduling system.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.395-398
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• 2011

This paper introduces stochastic cash-flow modeling integrated with simulation based scheduling. The system makes use of CPM schedule data exported from commercial scheduling software, computes the best fit probability distribution functions (PDFs) of historical activity durations, assigns the PDFs identified to respective activities, simulates the schedule network, computes the deterministic and stochastic project cash-flows, plots the corresponding cash flow diagrams, and estimates the best fit PDFs of overdraft and net profit of a project. It analyzes the effect of different distributions of activity durations on the distribution of overdrafts and net profits, and improves reliability compared to deterministic cash flow analysis.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.468-473
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• 2011

The goal of a project manager is generally to minimize the cost of the project and also to cope with uncertainty. This paper deals with the problem of project scheduling a set of activities satisfying precedence constraints in order to minimize the sum of the costs associated with the starting times of the activities in the network with imprecise activity durations, represented by means of interval or fuzzy numbers. So far this problem has been completely solved by several authors when the activities durations have crisp values. However, they do not consider the imprecision in activity durations in their models. Here the framework of possibility theory is proposed to solve this problem. In fuzzy arithmetic, usually, the interval calculations are used for the aim of complexity reduction and simplification. Thus the case of interval-valued durations is first addressed, and then extended to fuzzy intervals. A numerical example is used to illustrate the developed concept.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.454-457
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• 2001

All of the partner must manage continually scheduling for the successful project in construction. Besides, that is not a important only contracter's managing but also owner's managing which is a very important about project finishing in time. Especially, in the case of mega project, the owner has to manage progress of scheduling to control contractor. And the case of progress to delay or to change, owner, contractor, and inspector must make a plan of recovery scheduling. This study proposes a construction process model from IDEF Methodology.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.941-946
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• 2005

It is essential for project managers to make schedule adjustment based on their professional experience, in terms of rescheduling action discussed in this paper. This paper discusses the topics of resource-constrained construction rescheduling by modifying the concepts of manufacturing rescheduling. Moreover, the influence factors of construction rescheduling problems are investigated and identified in this paper. According to initial schedule plan and present progress, a new rescheduling mechanism based on Constraint Programming (CP) techniques is developed to reschedule projects with the objective of minimizing total project cost or duration, under three rescheduling policies. Through case study, the behavior of three different rescheduling policies is analyzed and discussed in this paper.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.484-491
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• 2022

A paradigm shift in teaching modular construction in higher education and K-12 is proposed as a means to increase the future adoption of the modular construction technique. To this effect, a new education module is presented to STEM educators. This education module is based on LEGOs and directed towards educators in the architecture, engineering, and construction (AEC) industry. The main objectives of the education module are to increase interest and knowledge of modular construction, acknowledge the benefits of using 3D design with 4D scheduling, and create a simulating hands-on educational opportunity. The education module is designed to allow participants to experience a hands-on simulation of modular construction and stick-built construction through building a LEGO project. Participants are challenged to find the advantages and disadvantages in both construction systems first-hand and record their findings. Results are presented from the preliminary testing of this education model on a group of construction management students at the University of Nevada, Las Vegas. Overall, the survey results showed that the LEGO education module was successful at achieving the project's three main objectives: 1) increasing the participants' interest and knowledge of modular construction through an interactive project; 2) increasing the participants' understanding of the benefits of 3D design with 4D scheduling over the use of 2D drawings; and 3) creating a simulating hands-on educational opportunity to help participants compare modular construction to stick-built construction. In the end, this proposed a new LEGO education module addressing the problems identified from this study with more participants.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.530-539
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• 2007

Many construction projects such as highways, pipelines, tunnels, and high-rise buildings typically contain repetitive activities. Research has shown that the Critical Path Method (CPM) is not efficient in scheduling linear construction projects that involve repetitive tasks. Linear Scheduling Method (LSM) is one of the techniques that have been developed since 1960s to handle projects with repetitive characteristics. Although LSM has been regarded as a technique that provides significant advantages over CPM in linear construction projects, it has been mainly viewed as a graphical complement to the CPM. Studies of scheduling linear construction projects with resource consideration are rare, especially with multiple resource constraints. The objective of this proposed research is to explore a resource assignment mechanism, which assigns multiple critical resources to all activities to minimize the project duration while satisfying the activities precedence relationship and resource limitations. Resources assigned to an activity are allowed to vary within a range at different stations, which is a combinatorial optimization problem in nature. A heuristic multiple resource allocation algorithm is explored to obtain a feasible initial solution. The Simulated Annealing search algorithm is then utilized to improve the initial solution for obtaining near-optimum solutions. A housing example is studied to demonstrate the resource assignment mechanism.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.137-139
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• 2012

This paper presents a system architecture and database of construction quality management system which encourages real time information tracking and monitoring. It improves the real time quality record tracking by using QR code technology in the project delivery. The advantages and issues relative to QR code and the database structures of the tracking system are presented. Conventional project scheduling system, operation modeling and analysis system, and quality management system are hybridized using QR code technology. The system improves project quality management by tracking the atomic tasks which consists of a construction process at the lowest level of construction hierarchy. It analyzes the quality records to determine the causes of abnormality and/or nonconformity. Using QR code technology, the construction quality management system may be more effective than the conventional one. It was confirmed that the quality management processes in construction project delivery can be more visible and controllable by integrating QR code technology, project scheduling system, and quality management system.

• Korean Journal of Construction Engineering and Management
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• v.5 no.6 s.22
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• pp.72-79
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• 2004

Critical Path-based project management has been applied to the construction projects with a goal of delivering projects within original costs and time estimates. These current project management methods, rarely make early finishes of construction Projects. In addition, current practices on time management seems not to take advantages of early finishes concepts due to student syndrome and Parkinson's Law, This research study applied the Theory of Constraints(n) in the estimation of construction project duration. While the TOC includes variety of management techniques, in this study, it refers to critical chain that has been used to develop the specific management technique in scheduling. The concept of critical chain is applied to this study to solve the problems associated with the current scheduling method. The efforts focus to solve the p개blems associated with current construction project scheduling methods by adopting both stochastic estimation technique and the concept of schedule buffer,

• Journal of Construction Engineering and Project Management
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• v.3 no.2
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• pp.21-34
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• 2013

Various risk factors affect construction projects. Due to the uncertainties created by risk factors, actual activity durations frequently deviate from the estimated durations in either favorable or adverse direction. For this reason, evaluation of schedule uncertainty is required to make decisions accurately when managing construction projects. In this regard, this paper presents a new computer simulation model - the Repetitive Schedule Risk Analysis Model (RSRAM) - to evaluate unit-based repetitive building project schedules under uncertainty when activity durations and risk factors are correlated. The proposed model utilizes Monte Carlo Simulation and a Critical Path Method based repetitive scheduling procedure. This new procedure concurrently provides the utilization of resources without interruption and the maintenance of network logic through successive units. Furthermore, it enables assigning variable production rates to the activities from one unit to another and any kind of relationship type with or without lag time. Details of the model are described and an example application is presented. The findings show that the model produces realistic results regarding the extent of uncertainty inherent in the schedule.