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In the construction industry, the primary concern of project-based organizations is how to achieve a balance between the optimal level of quality and the associated costs. The cost of quality (COQ) can help to achieve this balance. COQ in construction projects are dynamic in nature and hence should be considered as a complex interrelated system rather than a set of separate individual factors. This research aims to model the complex system of cost of quality and present policies for the reduction of those costs in construction projects. To implement the proposed model, the system dynamics approach is used to determine the impact of prevention and failure costs on the COQ and to analyze designed policies. The qualitative model i
Changes that occur during a project are a common and inevitable problem in the construction industry. Change is an important source of risk that could affect project performance significantly; thus, it is necessary to consider measures to predict and assess the risk of change. The purpose of this study was to develop a new framework for proactive change management in construction projects using fuzzy logic–based fault tree analysis. Fault tree analysis facilitates the evaluation of the change-formation process and assessment of the probability of change. In this study, fuzzy logic was used for quantitative analysis of the fault tree and to assess the impact of change on project objectives. A risk index was developed to assess the risk of
Believing in the fact that an activity can be performed through several methods or states, or that there may be several executive states for activities with different numbers of resources in real conditions, the scheduling obtained from different methods with different combinations of time, resources, and quality need to be evaluated and optimized. These are referred to as project scheduling problems with multistate resources. On the other hand, application of the theory of constraints to project management has led to the development of a novel approach in project planning and control known as the critical chain. The present paper seeks to use the critical chain technique and simultaneous time-cost-quality trade off. In this study, the mult
Considering that the mission of the project organization management is to create a commitment to the timetable, which prevents project delays and increases associated costs, and accept the fact that the delay in the completion time of the project results in the non-economization of the project, Therefore, the necessity of using proper planning and control methods seems necessary. One of the new methods used in project planning and control, which today focuses on many researchers, is the critical chain management method. In this research, multi-project scheduling with resource constraint in the critical-chain model has been investigated. In general, RCMPSP seeks to find the right sequence for project activities, so that the constraints of th
Implementation of infrastructure projects in a country is one of the key issues in the country economic growth. However, increasing the claim in the projects is inversely related to the objectives of the project due to the lack of understanding of the factors that create it and the impact of its factors on each other, especially in underground projects that we involve with many unknowns. In this research, for identifying the claim paths in DBF Tehran metro projects, after the library studies and review documents, we determined the main factors of the claim. Then, the effect of the causation factors on each other was analyzed using the system dynamics method, and finally, the most important paths that led to cost increases were identified as
The simultaneous reduction of the project cost and time has paramount importance in today's competitive world; however, it is necessary to balance the project time and cost because of the reduction asymmetry of the two factors in a project. How to balance the cost and time parameters in managing construction projects is also critical and there have always been some attempts made to provide different approaches to control it. Given the immense importance of considering resource constraints for project scheduling problems, and the proximity of the study conditions to the real world, resource constraints were also included. In a project, project managers need to be aware of resource constraints. As resource constraint scheduling
Nowadays traditional point of view is not able to meet the needs of construction project management. Therefore, the use of modern management approaches can be greatly helpful. The first step to reach this goal is to identify and verification variety of projects in terms of linear or network types, the difference in project and multi-project management, management and execute methods. In this research, critical chain management method is used instead of critical path method to provide more practical schedule. The proposed method solves a scheduling problem with time/resource tradeoff to provide a minimum-makespan deterministic schedule which will generally be a good starting point for project execution. Also to overcome the risk in the case,
In how to balance time and cost is crucial to construction project management. The main specification of time-cost trade off problem is discretization of the decision space to limited and accountable decision variables. In this situation the efficiency of the traditional methods decrease and applying of the evolutionary algorithm is necessary. The clever use of evolutionary algorithms allows us to solve many interesting and difficult problems and our ability to model complex problems increases tremendously. In this article use multi objective particle swarm optimization to solve two construction project management problems. These two projects include 7 and 70 activities with multiple modes. These problems are both in discrete domain includi
Cash-flow management is very important for contractors given that inadequate cash resources typically are the main causes for bankruptcy of construction companies. In comparison to most other industries, the construction industry is severely plagued by risk, and the success of construction projects usually depends on valuating all risks. However, conventional methods suggested by extant research on cash flow forecasting do not consider comprehensive identification of risk factors, interactions between the factors, and simultaneous occurrences of the factors. This study introduced a simple and appropriate probabilistic cash flow forecasting model using Bayesian Belief Networks (BBNs) to avoid bankruptcy of contractors by considering influenc
In the last decade, theory of constraint application in project management has led to make a new approach for project scheduling and control as a critical chain. In this paper, a multi-objective optimization model for multi-project scheduling on critical chain is investigated. The objectives include time, cost and quality. In order to solve the problem, a Simulated Annealing algorithm is developed and then analyzed to investigate the effect of each objective.. The number of activities in each project is not considered the same. Time, cost and quality values are calculated by solving the proposed algorithm and then the total utility amount is obtained. Sensitivity analysis is performed based on various values of each objective weight. Then,
In the last decade, theory of constraint application in project management lead to make a new approach for project scheduling and control as a critical chain. In this paper, a multi-objective optimization model for multi-project scheduling on critical chain is investigated. The objectives include time, cost and quality. In order to solve the problem, a Simulated Annealing algorithm is developed and then analyzed to investigate the effect of each objectives. The number of activities in each project is not considered the same. Time, cost and quality value are calculated by solving the proposed algorithm and then the total utility amount is obtained. Sensitivity analysis is performed based on various amount of each objective weights. Then the
The suggested cycle of project management maturity model generally include phases of evaluation, planning, improvement and finally cycle repeat which is largely based on a cycle known as Deming or PDCA.“Improvement Planning Phase” is the most important phase requiring development among these models that it is not discussed much. The major criteria for prioritization and planning in this phase were investigated in a research by authors. At first, the literature of subject is reviewed, by doing a series of interviews with project management consultants then prioritization criteria is identified, and eventually it is continued with more analysis on each of these criteria by distributing the questionnaire. The most significant criteria can
This paper surveys the studies on construction change systems and reveals some of the potential future works. It is tried to pick up the critical works to derive a true timeline of the systems. The findings show that leaping from best practice guides in late 1990s and generic process models in early 2000s to very advanced modelling environments in mid 2000s and early 2010s have made gaps along with opportunities for change researchers in order to develop some more easy and applicable models. Another finding is that there is a compelling similarity between the change and risk prediction models. So, integrating these two concepts, specifically from proactive management point of view, may lead to a synergy and help project teams avoid rework.
Metropolitan construction projects may be distinguished from other types of projects due to their specific nature. Issues with regard to purchase of property obstacles, a lack of accurate layout drawings for some underground facilities and, therefore, following probable changes in designs make it vital to have specific studies on risk analysis of such engineering projects. However, conventional methods offered in literature of risk analysis fail to consider the interactional mechanisms of risks and their simultaneous occurrence. This paper exploits the Multiply Connected Belief Network approach in MATLAB environment to analyse the simultaneous occurrence of risk factors on schedule delay of a highway project. The method of inference is thro
Delay is one of the problems occurring between owners and contractors. Deviation from base plans can be found using project control methods, continuous assessment of the schedule, determining progress percentages and earned value parameters. In such circumstances, conflicts might arise between contractor and owner as restoring project’s original schedule needs added expenditures by the contractor. Moreover, continuation of the previous procedure and late completion of the project will cause the owner damage.In this research, a mathematical model using game theory has been presented. The model investigates the behaviour and strategies of the parties involved in a delayed project through bargaining. It helps owners and contractors gain deep
Since their establishment, governments have been the main suppliers of resources for infrastructure projects, and provide a major source of tax revenue and revenue from national resources. On the one hand, there is a need to implement infrastructure projects in developing countries and increase national welfare, and on the other hand the external debt of Third World countries and the stress state budgets are rising. Further development of the private sector and emphasis on the privatization of government agencies in the 70s and 80s, created new ways to finance infrastructure projects, as an alternative to the use of public funds or borrowing from foreign sources. This resulted in the formation and development of various forms of public-priv
Minimizing both project time and cost is an important matter in today's competitive environment. Therefore trade-off between project time and cost is necessary. In projects, each activity can be started at different time points, depending on its precedence relationship and resource availability. Also cost and duration of the activities could be changed depending on the allocated resources. In addition, another strategy that affects the project total time and cost is resource leveling, which is applied to reduce excessive fluctuations in the resource usage. In this paper multi-mode resource-constrained project scheduling problem (MRCPSP), discrete time–cost trade-off problem (DTCTP) and also resource allocation and resource leveling proble