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Uncovering the hidden gem: The role of the undervalued quality in projects
In project management, the conventional focus on time and cost often overshadows quality’s undervalued, yet pivotal role. This study explores the nuanced dimensions of project success, centering on the Iron Triangle components: time, cost and quality (TCQ). Although quality is acknowledged in theoretical definitions, its economic significance and precise impact remain underexplored. This research addresses this gap by scrutinising the interplay between traditional success factors and project economic outcomes. By comparing projects with and without economic benefits, the study examines potential variations in TCQ influence. Furthermore, the research identifies specific traditional success factors associated with economic benefits and probes for a dominant factor with superior impact. A novel Project Unified Index (PUI) is introduced, enabling comprehensive economic performance assessment through TCQ analysis and statistical techniques. Intriguingly, the exploratory analysis reveals that time and quality possess more significant influence despite the apparent correlation between cost and profit. Quality emerges as a potential determinant, its significance often masked by meticulous measurement. This study underscores the paramount importance of quality, necessitating its redefinition across industries in a customer-centric manner. By repositioning quality as a decisive factor, this research reshapes perspectives on project management, steering future investigations towards a comprehensive understanding of quality’s pivotal role. The data for analysis were collected with the participation of a prominent professional project management association and a business master’s program in Hungary.
Journal Article
Optimizing of Discrete Time-Cost in Construction Projects Using New Adaptive Weight Formulations
In this paper, four new adaptive weight formulations are developed to enhance the performance of traditional Modified Adaptive Weight Approach (MAWA), which is the simplest way for solving the multi-objective optimization of discrete time-cost trade-off problem (DTCTP). Several numerical experiments are conducted to validate the newly proposed formulations. In addition, three meta-heuristic-based optimization algorithms are utilized to examine the variations within the results of the test instances. The proposed model provides several ways to solve DTCTP, as it includes different formulations and optimization algorithms. So, this model performs well for the medium and large-scale time-cost optimization problems on contrary to the traditional MAWA.
Journal Article
Fuzzy Multi-Mode Time–Cost–Quality Trade-Off Optimization in Construction Management of Hydraulic Structure Projects
Along with the increased use of water resources, some large water conservancy projects began construction to address power supply shortages and control flooding and drainage. As investment grows, construction cycles lengthen, external environmental impacts become bigger, and civil engineering project management becomes more complex. The real aim of the hydraulic-structure engineering project model is to manage ways of delivering the project on time while maintaining reasonable quality standards and building costs, to optimize project value. We note that the trade-off between conflicting objectives in a water conservancy project in an uncertain environment is a difficult task. To simulate the relationship between a project’s construction quality and its time limit, two new piecewise functions—a double exponential function and a quadratic function—were proposed, and then a fuzzy multi-mode discrete time–cost–quality trade-off concept for water-management projects was established. This model finds the best solution to an NP-hard problem using the particle-swarm optimization algorithm (PSO). A comparison of the calculations to previous studies validates the model and its computational approach. The optimized results of a water conservation project are provided as a conceptual framework for project planning and construction timeframes.
Journal Article
Duration prediction models for construction projects: In terms of cost or physical characteristics?
The purpose of this study is to investigate and to validate the ‘Bromilow’s Time-cost (BTC) model’ and the ‘Love
et al.
’s Time-Floor (LTF) model’ for Turkish public building projects, to check their appropriateness and to compare their prediction performances on project duration. The LTF model formulates the project duration in terms of gross floor area & floor numbers while the BTC model formulated it in terms of cost. Despite the consideration of the different characteristics, both models were inspired from Australian building projects. The study also presents ‘best-fit models’ as a benchmark for the BTC and the LTF models in order to fill the gap in construction duration predictions. The research data were collected from a total of 530 Turkish public building projects which were completed in seven geographic regions by performing an archive search work. 80% of the total data (i.e. from 424 projects) were used to establish the models while the remaining 20% (106 projects) were used for validation. Eight project characteristics of; total construction area, building height, gross floor area, floor numbers, contract sum, actual cost, contract duration and the actual duration were collected. Since there was no central archiving conduction to obtain these characteristics, more than a thousand tender documents were examined, and for 530 documents these characteristics were available. Consequently, it was found that the BTC model is superior to the LTF model, which confirms that ‘cost’ is a more significant predictor of the ‘duration’ than ‘gross floor area’ & ‘floor numbers’. However, the proposed ‘best-fit model’ indicated that the ‘area’ and the ‘height’ are the main predictors of the ‘duration’ as well as the ‘cost’.
Journal Article
Balanced strategy based on environment and user benefit-oriented carpooling service mode for commuting trips
Besides saving money and providing convenience, carpooling can result in environmental benefits to society; therefore, it is important to promote and improve daily carpooling services. However, some conflicts related to carpooling match rates and environmental protection have been influencing user satisfaction. To broaden the carpooling service scope and improve service flexibility, an environment and user benefit-oriented carpooling service model was developed that included mixed user groups, different user types, multiple origin and destination pairs, a time window and user attitudes, and considered the cost and time efficiency requirements of the users to guarantee individual benefits and provide more reasonable matches. A 0–1 nonlinear optimization model was built to describe the model and an improved genetic algorithm based on a nearby matching principle designed to find the optimal solution. Finally, a case simulation from Chengdu city was conducted to demonstrate the effectiveness of the proposed model and the influence of different user attitudes on the carbon emissions and match rates, from which it was found that the proposed carpooling mode was able to provide a more systematic carpooling plan, avoid the increased carbon emissions from potential mismatching due to time and efficiency losses, and guarante the maximum social benefit.
Journal Article
Multi-objective optimization of discrete time-cost tradeoff problem in project networks using non-dominated sorting genetic algorithm
The time-cost tradeoff problem is one of the most important and applicable problems in project scheduling area. There are many factors that force the mangers to crash the time. This factor could be early utilization, early commissioning and operation, improving the project cash flow, avoiding unfavorable weather conditions, compensating the delays, and so on. Since there is a need to allocate extra resources to short the finishing time of project and the project managers are intended to spend the lowest possible amount of money and achieve the maximum crashing time, as a result, both direct and indirect costs will be influenced in the project, and here, we are facing into the time value of money. It means that when we crash the starting activities in a project, the extra investment will be tied in until the end date of the project; however, when we crash the final activities, the extra investment will be tied in for a much shorter period. This study is presenting a two-objective mathematical model for balancing compressing the project time with activities delay to prepare a suitable tool for decision makers caught in available facilities and due to the time of projects. Also drawing the scheduling problem to real world conditions by considering nonlinear objective function and the time value of money are considered. The presented problem was solved using NSGA-II, and the effect of time compressing reports on the non-dominant set.
Journal Article
Microgeography and the Direction of Inventive Activity
I provide novel empirical evidence grounded in an original theoretical framework to explain why colocation matters for the rate, direction, and quality of scientific collaboration. To address endogeneity concerns due to selection into colocation and matching, I exploit the constraints imposed on the spatial allocation of labs on the Jussieu campus of Paris by the removal of asbestos from its buildings. Consistent with search costs constituting a major friction to collaboration, colocation increases the likelihood of joint research by 3.5 times, an effect that is mostly driven by lab pairs that face higher search costs ex ante. Furthermore, separation does not negatively affect collaboration between previously colocated labs. However, while colocated labs grow increasingly similar in topics and literature cited, separated ones embark on less correlated research trajectories. Research outcomes, instead, seem to be mostly influenced by how distance affects execution costs: after colocation, labs are more likely to pursue both lower-quality projects (a selection effect) and high-quality projects (an effort effect). Opposite effects on quality are observed after separation. Whereas search costs affect which scientists are likely to collaborate together, execution costs shape the quality of their output.
The online appendix is available at
https://doi.org/10.1287/mnsc.2017.2798
.
This paper was accepted by Ashish Arora, entrepreneurship and innovation.
Journal Article
Time–cost relationship for predicting construction duration
Reliable estimates of project cost and duration are necessary inputs for decision-making in the earliest stages of construction projects. As little data is available, the estimates can only rest upon records of similar completed schemes. The tools that use such records to facilitate project planning continue to be the object of interest of researchers. This paper investigates the applicability of a simple regression model for the prediction of road construction duration on the basis of early cost estimates. Statistical validity of the model was confirmed, and its predictive ability tested.
Journal Article
Models to Analyze Risk in Time and Cost Estimation of Tunneling Projects
Time and cost estimation of tunneling projects is usually performed in a deterministic manner. However, because the deterministic approach is not capable of dealing with uncertainty, probabilistic methods have been developed over the years to better account for this problem. Three models of this type are the Decision Aids for Tunneling (DAT) and two models developed at KTH Royal Institute of Technology and the Czech Technical University in Prague. To conduct a probabilistic time and cost estimation, it is important to understand and account for not only the uncertain factors that affect the project time and cost but also the involved parties’ different interests and contractual responsibilities. This paper develops a risk model for the specific purpose of time and cost estimation of tunneling projects. In light of this model, the practical application of the three probabilistic models is discussed from a risk-aware decision-maker’s perspective. The acquired insights can be helpful in increasing the experts’ risk-awareness in modeling time and cost of tunneling projects.
Journal Article