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Sustainable development of any country to some extent depends on successful accomplishment of construction projects, particularly infrastructures. Contractors have a key role in the success of these projects. Hence, the selection of a competent contractor as a complicated and hard decision process has a vital importance in the destiny of any construction project. Contractor selection is in essence a multicriteria decision-making that ought to encompass so many aspects of the project and the client’s requirements on one hand and the capabilities and past records of the contractors on the other hand. Failure in selecting a competent contractor may cause time and cost overruns; quality shortcomings; increasing in claims, disputes and change orders; and even failure of the project. In spite of deficiencies of selecting a contractor by the rule of “the lowest bid price”, it still prevails in many countries including Iran. In this paper, a new contractor selection model based on the best-worst method (BWM) and well-known Fuzzy-VIKOR techniques is proposed as a solution to overcome the deficiencies of the traditional “lowest bid price” rule. An illustrative example of a water channel construction project verified the applicability of the proposed model in practice.
Aziz Naghizadeh Vardin; Ramin Ansari; Mohammad Khalilzadeh; Jurgita Antucheviciene; Romualdas Bausys. An Integrated Decision Support Model Based on BWM and Fuzzy-VIKOR Techniques for Contractor Selection in Construction Projects. Sustainability 2021, 13, 6933 .
AMA StyleAziz Naghizadeh Vardin, Ramin Ansari, Mohammad Khalilzadeh, Jurgita Antucheviciene, Romualdas Bausys. An Integrated Decision Support Model Based on BWM and Fuzzy-VIKOR Techniques for Contractor Selection in Construction Projects. Sustainability. 2021; 13 (12):6933.
Chicago/Turabian StyleAziz Naghizadeh Vardin; Ramin Ansari; Mohammad Khalilzadeh; Jurgita Antucheviciene; Romualdas Bausys. 2021. "An Integrated Decision Support Model Based on BWM and Fuzzy-VIKOR Techniques for Contractor Selection in Construction Projects." Sustainability 13, no. 12: 6933.
Today, the construction industry has to turn into one of the major industries, which covers a wide range of dependent industries. Rapid changes in the construction environment require a great deal of effort for a company or organization to maintain survival and growth. The life of companies and organizations in the field of construction depends on the way they manage their projects. Achieving project success is a major goal of project managers. A method of evaluating and controlling the project success is to apply project performance management. As a result of the studies, the most important key performance indicators, their relevant sources and references, and the relationships related to the quantification of indicators and their relationships with each other have been introduced and described. These results could help researchers in the future to obtain information and resources related to each index. Safety, environment, cost, profitability, scheduling, productivity, sustainability, quality, client satisfaction, and team satisfaction are the most important indicators.
Shohreh Moradi; Ramin Ansari; Roohollah Taherkhani. A Systematic Analysis of Construction Performance Management: Key Performance Indicators from 2000 to 2020. Iranian Journal of Science and Technology, Transactions of Civil Engineering 2021, 1 -17.
AMA StyleShohreh Moradi, Ramin Ansari, Roohollah Taherkhani. A Systematic Analysis of Construction Performance Management: Key Performance Indicators from 2000 to 2020. Iranian Journal of Science and Technology, Transactions of Civil Engineering. 2021; ():1-17.
Chicago/Turabian StyleShohreh Moradi; Ramin Ansari; Roohollah Taherkhani. 2021. "A Systematic Analysis of Construction Performance Management: Key Performance Indicators from 2000 to 2020." Iranian Journal of Science and Technology, Transactions of Civil Engineering , no. : 1-17.
This study develops hybrid modeling and algorithmic frameworks for analyzing the mutual effects of multiple sources of uncertainty on the quality and the robustness of construction schedules. To cope with multiple sources of disruptions, i.e., random resource failures and severe weather conditions, this paper develops a simulation-optimization model that aims to generate delay resistant project schedules. The Variable Neighborhood Search (VNS) is hybridized with an event-driven simulation framework to generate efficient and robust solutions for computationally expensive resource-constrained project scheduling problems (RCPSP). The simulation experiments have been carried out by a flexible modeling framework that can be adopted by project experts to design construction schedules subject to the uncertainty associated with the multiple resource failure. The problem is mathematically formulated as a bi-objective optimization model aiming to minimize the project makespan and maximize a novel surrogate robustness function simultaneously. The computational results of the proposed VNS method have been compared with those obtained from the commercial optimization solvers. The simulation-optimization model’s application is demonstrated through a case study of the hydropower plant construction project with multiple renewable and non-renewable resources. Based on an extensive statistical analysis of real-life scenarios, this study contributes to a trade-off analysis of project makespan and robustness in construction projects. The t-test statistical analysis results indicate the significance of the project’s average delay reduction by implementing the robust project schedule. The outcomes confirm that the designed framework can generate a more efficient project schedule with a higher rate of protection compared with the existing robust approaches.
Ramin Ansari. Dynamic Optimization for Analyzing Effects of Multiple Resource Failures on Project Schedule Robustness. KSCE Journal of Civil Engineering 2021, 25, 1515 -1532.
AMA StyleRamin Ansari. Dynamic Optimization for Analyzing Effects of Multiple Resource Failures on Project Schedule Robustness. KSCE Journal of Civil Engineering. 2021; 25 (5):1515-1532.
Chicago/Turabian StyleRamin Ansari. 2021. "Dynamic Optimization for Analyzing Effects of Multiple Resource Failures on Project Schedule Robustness." KSCE Journal of Civil Engineering 25, no. 5: 1515-1532.
Uncertainties affect the scheduling of construction projects. They are among the main causes of delays in construction projects, which increase project costs and reduce project quality. Uncertainties in scheduling affect the duration of activities. Under such conditions, the duration of each activity is influenced by several risk factors; however, previous Bayesian scheduling models considered the effects of one or no factor on the duration of tasks. Also, all parameters of the scheduling network were not considered in those models. In this study, given the causal relationships between uncertainties and their multiple effects on the task duration, a duration model is presented. Next, the effects of uncertainties on all scheduling parameters are applied to Bayesian object-oriented networks through mapping precedence networks. Object-oriented Bayesian networks are a new project management approach to risk assessment and uncertainties in decision-making. This approach is quite effective in considering the causal structure of risk variables and assessing the repetitive structure of precedence networks in large-scale scheduling networks. The project completion time, total slack, delays, as well as other scheduling parameters are estimated using the model proposed, which is titled the Bayesian Precedence Network.
Kiazad Abbasnezhad; Ramin Ansari; Mahdi Mahdikhani. Schedule Risk Assessments Using a Precedence Network: An Object-Oriented Bayesian Approach. Iranian Journal of Science and Technology, Transactions of Civil Engineering 2020, 1 -17.
AMA StyleKiazad Abbasnezhad, Ramin Ansari, Mahdi Mahdikhani. Schedule Risk Assessments Using a Precedence Network: An Object-Oriented Bayesian Approach. Iranian Journal of Science and Technology, Transactions of Civil Engineering. 2020; ():1-17.
Chicago/Turabian StyleKiazad Abbasnezhad; Ramin Ansari; Mahdi Mahdikhani. 2020. "Schedule Risk Assessments Using a Precedence Network: An Object-Oriented Bayesian Approach." Iranian Journal of Science and Technology, Transactions of Civil Engineering , no. : 1-17.
The management and control of megaprojects are incredibly complex. Difficulties occur due to unexpected changes and errors. To effectively manage disruptive changes, reworks, and errors, project managers are required to consider the dynamic behavior of feedback loops that cause delays and disturbances. The system dynamics (SD) modeling approach has been used in the past few decades to address this need for the analysis and improvement of project performance. This paper discusses how changes in dynamics can influence the performance of a project. The SD model was utilized to improve project planning and simulate change-management policies for an Iranian project in the petrochemical industry. This study contributes by developing a dynamic simulation model for effective formulation of project change-management policies by taking into account the time, cost, quality, resource, and financial indicators. The model enables the decision maker to compare alternative change-management policies, e.g., funding, outsourcing activities, schedule adjustment, and labor control in terms of project performance indicators. Aided by a case study and an SD methodology, a comparative analysis of change-management policies was provided. Results indicated that resource planning has an essential role in the project performance improvement.
Ramin Ansari. Dynamic Simulation Model for Project Change-Management Policies: Engineering Project Case. Journal of Construction Engineering and Management 2019, 145, 05019008 .
AMA StyleRamin Ansari. Dynamic Simulation Model for Project Change-Management Policies: Engineering Project Case. Journal of Construction Engineering and Management. 2019; 145 (7):05019008.
Chicago/Turabian StyleRamin Ansari. 2019. "Dynamic Simulation Model for Project Change-Management Policies: Engineering Project Case." Journal of Construction Engineering and Management 145, no. 7: 05019008.
Delays and disruptions are extremely challenging issues to deal with in project management. In this article, a novel optimization approach to the buffer sizing method is introduced aimed at maximizing the robustness of the buffered schedule generated. The measures affecting the buffer sizing include the network complexity, flexibility, criticality, and robustness. The methodology presented is based on the critical chain project management concept, yet novel metrics are introduced to cover the uncertainties connected with the critical and non-critical chains. The overall purpose of the approach is to investigate the necessity and design of a decision support system to improve the process of critical chain project management. Utilizing a robust and flexible framework, this study tries to efficiently determine the size of feeding and project buffers. The weaknesses of the current critical chain project management approaches were overcome in the critical chain project management, and a new method was developed based on the integration of simulation and optimization techniques. In order to verify the efficiency of the method proposed, a case study is conducted. The outcomes indicate that the robust buffer allocation method proposed yields more stable project schedules, as against the traditional buffer sizing methods.
Ramin Ansari; Ahmad Makui; Parviz Ghoddousi. An Algorithmic Framework for Improving the Performance of the Critical Chain Buffer Sizing Method. Scientia Iranica 2017, 1 .
AMA StyleRamin Ansari, Ahmad Makui, Parviz Ghoddousi. An Algorithmic Framework for Improving the Performance of the Critical Chain Buffer Sizing Method. Scientia Iranica. 2017; ():1.
Chicago/Turabian StyleRamin Ansari; Ahmad Makui; Parviz Ghoddousi. 2017. "An Algorithmic Framework for Improving the Performance of the Critical Chain Buffer Sizing Method." Scientia Iranica , no. : 1.
In this study, a multi-attribute buffer sizing method is proposed aimed at maximizing the robustness of the buffered schedule generated. The project attributes concerning the network complexity, flexibility criteria, criticality index and robustness measures are considered through the buffer sizing process. The methodology presented is based on the critical chain buffer management methodology, yet innovative metrics are presented to deal with the uncertainties associated with the critical and non-critical chains. The buffer sizing method proposed eliminates the previous limitations and attempts to economically determine the size of the feeding and project buffers. Additionally, a risk analysis is performed to examine the effects of external factors on buffer sizes. The weaknesses of the existing buffer sizing approaches were overcome in the critical chain project management, and a novel buffer sizing method was established based on internal and external risk aspects. A simulation experiment is conducted in order to prove the effectiveness of the method proposed. The computational results of implementing the method on a real case study specify that the method proposed generates more stable project plans at a lower cost, compared with those generated using traditional buffer sizing methods.
Parviz Ghoddousi; Ramin Ansari; Ahmad Makui. A risk-oriented buffer allocation model based on critical chain project management. KSCE Journal of Civil Engineering 2016, 21, 1536 -1548.
AMA StyleParviz Ghoddousi, Ramin Ansari, Ahmad Makui. A risk-oriented buffer allocation model based on critical chain project management. KSCE Journal of Civil Engineering. 2016; 21 (5):1536-1548.
Chicago/Turabian StyleParviz Ghoddousi; Ramin Ansari; Ahmad Makui. 2016. "A risk-oriented buffer allocation model based on critical chain project management." KSCE Journal of Civil Engineering 21, no. 5: 1536-1548.
Unpredictable uncertainties cause delays and additional costs for projects. Often, when using traditional approaches, the optimizing procedure of the baseline project plan fails and leads to delays. In this study, a two-stage multi-objective buffer allocation approach is applied for robust project scheduling. In the first stage, some decisions are made on buffer sizes and allocation to the project activities. A set of Pareto-optimal robust schedules is designed using the meta-heuristic non-dominated sorting genetic algorithm (NSGA-II) based on the decisions made in the buffer allocation step. In the second stage, the Pareto solutions are evaluated in terms of the deviation from the initial start time and due dates. The proposed approach was implemented on a real dam construction project. The outcomes indicated that the obtained buffered schedule reduces the cost of disruptions by 17.7% compared with the baseline plan, with an increase of about 0.3% in the project completion time.
Parviz Ghoddousi; Ramin Ansari; Ahmad Makui. An improved robust buffer allocation method for the project scheduling problem. Engineering Optimization 2016, 49, 718 -731.
AMA StyleParviz Ghoddousi, Ramin Ansari, Ahmad Makui. An improved robust buffer allocation method for the project scheduling problem. Engineering Optimization. 2016; 49 (4):718-731.
Chicago/Turabian StyleParviz Ghoddousi; Ramin Ansari; Ahmad Makui. 2016. "An improved robust buffer allocation method for the project scheduling problem." Engineering Optimization 49, no. 4: 718-731.
Ramin Ansari; Eghbal Shakeri; Ali Raddadi. Framework for Aligning Project Management with Organizational Strategies. Journal of Management in Engineering 2015, 31, 04014050 .
AMA StyleRamin Ansari, Eghbal Shakeri, Ali Raddadi. Framework for Aligning Project Management with Organizational Strategies. Journal of Management in Engineering. 2015; 31 (4):04014050.
Chicago/Turabian StyleRamin Ansari; Eghbal Shakeri; Ali Raddadi. 2015. "Framework for Aligning Project Management with Organizational Strategies." Journal of Management in Engineering 31, no. 4: 04014050.