Browsing by Author "Aminbakhsh, Saman"
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Item A COMPARATIVE STUDY ON RESOURCE LEVELING CAPABILITIES OF COMMERCIAL PROJECT MANAGEMENT SOFTWARE PACKAGES FOR PROJECTS WITH RESOURCE CONSTRAINTS(2022-01-14) Hussein Farooq Albayati, Noor; Aminbakhsh, SamanIn construction project management the critical path method (CPM) is the most commonly used technique for project scheduling. Although this technique provides many advantages for project managers, it cannot efficiently deal with the allocation of the resources. Therefore, other techniques have been introduced to address resource allocation requirements of the projects. Of these techniques, Resource Leveling aims to minimize the fluctuation in resource usage histograms obtained by CPM without violating the resource constraints, while securing the shortest CPM duration. Resource leveling is vital for effective utilization of project resources (e.g., manpower, machinery, and equipment) as it helps precluding intermittent usage of the resources. Keeping the resource usage at a relatively constant level would result in a decrease in the overall project cost as the additional costs required to demobilize and remobilize the resources will be minimized. The main objective of this study is to analyze effectiveness and efficiency of the most widely used commercial project management software packages in solving resource leveling problems with constrained resources. To this end, the most recent versions – as per the date of this study – of three software packages, namely, Microsoft Project Professional 2019, Primavera P6 Professional 2019, and Asta Powerproject version 15.0.01.489 are examined. The performance of the practiced software are evaluated based on thirteen different priority rules over a set of problem instances available in the literature. The practiced problems include 640 instances providing a diverse combination of network complexity, activity number, and resource type number. Results obtained by the software are also compared with the solutions provided by the Serial Scheduling Scheme – a heuristic method. The findings of the leveling process reveal while all the three software packages manage to provide comparable results, Asta PowerProject transpire to be the all-round best performing method while Primavera sports the fastest leveling module. This study also sheds light on the challenges and practical hurdles to utilization of the aforementioned software for resource leveling purposes.Item A META-HEURISTIC FOR THE DISCRETE TIME-COST-QUALITY TRADE-OFF PROBLEM WITH GENERALIZED PRECEDENCE RELATIONSHIPS(2022-01-14) Abdulsattar, Abdulrahman M.; Aminbakhsh, SamanBuilding projects can certainly be considered as one of the most crucial elements that contributes greatly to economic growth of a nation. They facilitate developments in other industries too by providing appropriate working spaces and the means for mobilization of resources (e.g., office building, hospitals, schools, highways). Through unique public or private bids, the governments and stakeholders aim to achieve reasonable prices for such projects with minimum possible makespans and the best quality. Evidently, weighing the available offers and coming up with an optimal decision can pose challenges for the decision-makers. In this regard, generation of a tool that helps decision-makers strike a proper balance among the conflicting project objectives (i.e., time, cost, and quality) is imperative. To this end, this study proposes a method which assists in selection of the best compromise choices among the options available for each of the project activities. In addition to time and cost, the proposed method is designed to bring the quality aspect into the equation as well. To quantify the quality, a value referring to the weighted importance and performance of each activity is used. The proposed method is based on a slightly modified Genetic Algorithm (GA) that incorporates the domination concept for selection of the best solutions out of the potential candidates. The GA-based method is capable of handling unlimited number of precedence relationships for each activity and above all, it is able to capture and unravel any type of logical relationship. This very feature significantly improves the practical relevance of this research as parallelization of activities is a common practice in real-life projects. Planners by benefitting from the various types of relationships (i.e., Start-to-Start, Start-to-Finish, Finish-to-Start, and Finish-to Finish) and the concept of lag time frequently introduce parallelization into the network. Overlapped activities, in turn, help reduce the unwanted idle times and speed up the project significantly. In order to demonstrate the application and to evaluate the effectiveness of the proposed model, it is used for solution of three different Time-Cost-Quality (TCQ) tradeoff problems, two of which are generated within the context of this thesis. The practiced instances include a small benchmark TCQ problem with 18 activities taken from the literature in addition to more complex 29- and 63-activity TCQ problems produced herein based on existing 29- and 63-activity time-cost tradeoff problems, respectively. The obtained results reveal both the effectiveness of the proposed model and the possibility to be used by the planners amidst making arduous decisions.Article A Transformative Solution for Construction Safety: Blockchain-based System for Accident Information Management(Journal of Industrial Information Integration, 2023-07-05) Ahmadisheykhsarmast, Salar; Aminbakhsh, Saman; Sönmez, Rıfat; Uysal, FurkanEffective management of accident information is a crucial component of safety management within the construction industry, as it reflects the safety performance of the company and allows them to identify the root causes of accidents and prevent similar accidents in the future. However, existing safety information systems provide self-owned, isolated, and centralized environments and fail to present a secure, transparent, and trustworthy platform for monitoring and management of accident information. To address these issues, this paper presents a novel decentralized blockchain-based system for accident/incident information management of construction projects. The proposed system leverages the benefits and advantages of blockchain, smart contracts, and decentralized IPFS storage to address the security transparency, tampering, and trustworthiness issues of the conventional approaches. The proposed system is simulated by using real-world construction accident data to demonstrate how blockchain technology can provide a novel solution to assure security, transparency, authenticity, availability, and immutability of the accident/incident data for improving safety management.Item GENETIC-ALGORITHM-BASED OPTIMIZATION APPROACH FOR TIME COST TRADE-OFF PROBLEM WITH GENERALIZED PRECEDENCE RELATIONSHIPS(2022-01-21) Hama Faraj Ahmed Ahmed, Ary; Aminbakhsh, SamanDecreasing the overall cost of a project through reductions in its duration can be considered as one of the main goals of any construction project. Shortening the duration can be achieved by accelerating the construction project by utilization of more efficient construction techniques; that is, by allocation of additional and/or more productive resources. However, expedition of the project schedule will obviously incur extra costs due to implementation of high-price construction techniques. Meanwhile, this reduction of time might be plausible only up to a certain limit. Stemming from the highly challenging nature of this trade-off between the overall cost and the duration of the projects, still no planning software package provides any features for tackling it. The lack of such functionality has encouraged development of numerous optimization algorithm by several researchers for achieving a compromise between the conflicting objectives of time and cost. Despite a great deal of effort, a large body of literature ignore the various types of precedence relationships which are frequently incorporated in practice. In this thesis a Simulated Annealing-based Genetic Algorithm is proposed for solution of this optimization problem which is referred to as the time-cost trade-off problem (TCTP) in the construction context. The proposed hybrid GA is designed to ensure fast convergence without sacrificing the quality of the solutions found. The proposed optimization method is capable of solving TCTPs with generalized precedence relationships with realistic overlapping of activities. Performance of the hybrid GA proposed herein is tested over a wide range of frequently used problems and the results are compared with various existing methods. Practicality of this algorithm is also validated by fitting the model to a large-scale real-case construction project. As a result of validation, the utility of the proposed algorithm is illustrated which also highlights how it can help both the client and the contractor in speeding up the project without exceeding the budget.Item RISK ASSESSMENT OF CONSTRUCTION PROJECTS FOR OIL AND GAS PROCESSING FACILITIES IN IRAQ(2022-01-17) Samir Dawood Dawood, Muhanned; Aminbakhsh, Saman; Alfatlawi, Thair Jabbar MizhirOil and gas are among of the most important economic resources and are considered the main artery of natural reserves in Iraq. Companies and institutions involved in construction of processing facilities associated with such reserves have a pivotal role in the global economy. On the other hand, Iraq’s capital budget highly depends on the proportion of oil revenues. In this vein, many researchers have attempted to identify and analyze the risks pertinent to construction projects related to oil and gas processing facilities and have proposed various methods and practical plans for eliminating or reducing their effects on the critical success factors of time, cost, and quality. The aim of this study, analogously, is to determine the risks threatening the desired balance between the main objectives of construction projects in oil and gas sector of Iraq. For this purpose, findings of the literature review are used to develop an online questionnaire including 70 risk items widely referred to in the scientific arena in order to collect empirical data from academia, professionals, and decision-making authorities. Participants are chosen from different governmental and non governmental institutions and/or companies, namely, Iraq’s Ministry of Oil, Kuwait Energy, University of Baghdad, Kerbala and Al-Dorra refineries. General information related to 143 experts and their risk ratings are compiled using a five-point Likert scale. Grouped under eight risk categories, the level of likelihood and impact for each of the risk factors are determined. Based on the data collected from the respondents, risk matrices are developed to assess and rank the identified risks, whereof, the associated risk responses are proposed herein for the ten highest-ranked factors. SPSS and Microsoft Excel programs are used for statistical analysis of the collected responses and the consistency of the data is validated by using Cronbach’s Alpha reliability coefficient. Results points out ‘Instability in global oil and gas prices’ and ‘Delay in payments to the workforce’ to be the most significant risk items than can indirectly affect the success of the projects.