Matching Items (5)
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- All Subjects: management
- All Subjects: Polymers--Deterioration.
- Genre: Academic theses
- Creators: El Asmar, Mounir
Description
Alternative Project Delivery Methods (APDMs), namely Design Build (DB) and Construction Manager at Risk (CMAR), grew out of the need to find a more efficient project delivery approach than the traditional Design Bid Build (DBB) form of delivery. After decades of extensive APDM use, there have been many studies focused on the use of APDMs and project outcomes. Few of these studies have reached a level of statistical significance to make conclusive observations about APDMs. This research effort completes a comprehensive study for use in the horizontal transportation construction market, providing a better basis for decisions on project delivery method selection, improving understanding of best practices for APDM use, and reporting outcomes from the largest collection of APDM project data to date. The study is the result of an online survey of project owners and design teams from 17 states representing 83 projects nationally. Project data collected represents almost six billion US dollars. The study performs an analysis of the transportation APDM market and answers questions dealing with national APDM usage, motivators for APDM selection, the relation of APDM to pre-construction services, and the use of industry best practices. Top motivators for delivery method selection: the project schedule or the urgency of the project, the ability to predict and control cost, and finding the best method to allocate risk, as well as other factors were identified and analyzed. Analysis of project data was used to compare to commonly held assumptions about the project delivery methods, confirming some assumptions and refuting others. Project data showed that APDM projects had the lowest overall cost growth. DB projects had higher schedule growth. CMAR projects had low design schedule growth but high construction schedule growth. DBB showed very little schedule growth and the highest cost growth of the delivery methods studied. Best practices in project delivery were studied: team alignment, front end planning, and risk assessment were identified as practices most critical to project success. The study contributes and improves on existing research on APDM project selection and outcomes and fills many of the gaps in research identified by previous research efforts and industry leaders.
ContributorsBingham, Evan Dale (Author) / Gibson Jr., G. Edward (Thesis advisor) / El Asmar, Mounir (Thesis advisor) / Bearup, Wylie (Committee member) / Arizona State University (Publisher)
Created2014
Description
In today's era a lot of the construction projects suffer from time delay, cost overrun and quality defect. Incentive provisions are found to be a contracting strategy to address this potential problem. During last decade incentive mechanisms have gained importance, and they are starting to become adopted in the construction projects. Most of the previous research done in this area was purely qualitative, with a few quantitative studies. This study aims to quantify the performance of incentives in construction by collecting the data from more than 30 projects in United States through a questionnaire survey. First, literature review addresses the previous research work related to incentive types, incentives in construction industry, incentives in other industry and benefits of incentives. Second, the collected data is analyzed with statistical methods to test the significance of observed changes between two data sets i.e. incentive projects and non-incentive projects. Finally, the analysis results provide evidence for the significant impact of having incentives; reduced the cost and schedule growth in construction projects in United States.
ContributorsPaladugu, Bala Sai Krishna (Author) / El Asmar, Mounir (Thesis advisor) / Ernzen, James (Committee member) / Sullivan, Kenneth (Committee member) / Arizona State University (Publisher)
Created2015
Description
Despite advancements in construction and construction-related technology, capital project performance deviations, typically overruns, remain endemic within the capital projects industry. Currently, management is generally unaware of the current status of their projects, and thus monitoring and control of projects are not achieved effectively. In an ever-increasing competitive industry landscape, the need to deliver projects within technical, budgetary, and schedule requirements becomes imperative to sustain a healthy return on investment for the project stakeholders. The fact that information lags within the capital projects industry has motivated this research to find practices and solutions that facilitate Instantaneous Project Controls (IPC).
The author hypothesized that there are specific practices that, if properly implemented, can lead to instantaneous controls of capital projects. It is also hypothesized that instantaneous project controls pose benefits to project performance. This research aims to find practices and identify benefits and barriers to achieving a real-time mode of control. To achieve these objectives, several lines of inquiry had to be pursued. A panel of 13 industry professionals and three academics collaborated on this research project. Two surveys were completed to map the current state of project control practices and to identify state-of-the-art or ideal processes. Ten case studies were conducted within and outside of the capital projects industry to identify practices for achieving real-time project controls. Also, statistical analyses were completed on retrospective data for completed capital projects in order to quantify the benefits of IPC. In conclusion, this research presents a framework for implementing IPC across the capital projects industry. The ultimate output from this research is procedures and recommendations that improve project controls processes.
The author hypothesized that there are specific practices that, if properly implemented, can lead to instantaneous controls of capital projects. It is also hypothesized that instantaneous project controls pose benefits to project performance. This research aims to find practices and identify benefits and barriers to achieving a real-time mode of control. To achieve these objectives, several lines of inquiry had to be pursued. A panel of 13 industry professionals and three academics collaborated on this research project. Two surveys were completed to map the current state of project control practices and to identify state-of-the-art or ideal processes. Ten case studies were conducted within and outside of the capital projects industry to identify practices for achieving real-time project controls. Also, statistical analyses were completed on retrospective data for completed capital projects in order to quantify the benefits of IPC. In conclusion, this research presents a framework for implementing IPC across the capital projects industry. The ultimate output from this research is procedures and recommendations that improve project controls processes.
ContributorsAbbaszadegan, Amin (Author) / Grau Torrent, David (Thesis advisor) / El Asmar, Mounir (Committee member) / Gibson, Jr., G. Edward (Committee member) / Arizona State University (Publisher)
Created2016
Description
With the growing popularity of 3d printing in recreational, research, and commercial enterprises new techniques and processes are being developed to improve the quality of parts created. Even so, the anisotropic properties is still a major hindrance of parts manufactured in this method. The goal is to produce parts that mimic the strength characteristics of a comparable part of the same design and materials created using injection molding. In achieving this goal the production cost can be reduced by eliminating the initial investment needed for the creation of expensive tooling. This initial investment reduction will allow for a wider variant of products in smaller batch runs to be made available. This thesis implements the use of ultraviolet (UV) illumination for an in-process laser local pre-deposition heating (LLPH). By comparing samples with and without the LLPH process it is determined that applied energy that is absorbed by the polymer is converted to an increase in the interlayer temperature, and resulting in an observed increase in tensile strength over the baseline test samples. The increase in interlayer bonding thus can be considered the dominating factor over polymer degradation.
ContributorsKusel, Scott Daniel (Author) / Hsu, Keng (Thesis advisor) / Sodemann, Angela (Committee member) / Kannan, Arunachala M (Committee member) / Arizona State University (Publisher)
Created2017
Description
The solar energy sector has been growing rapidly over the past decade. Growth in renewable electricity generation using photovoltaic (PV) systems is accompanied by an increased awareness of the fault conditions developing during the operational lifetime of these systems. While the annual energy losses caused by faults in PV systems could reach up to 18.9% of their total capacity, emerging technologies and models are driving for greater efficiency to assure the reliability of a product under its actual application. The objectives of this dissertation consist of (1) reviewing the state of the art and practice of prognostics and health management for the Direct Current (DC) side of photovoltaic systems; (2) assessing the corrosion of the driven posts supporting PV structures in utility scale plants; and (3) assessing the probabilistic risk associated with the failure of polymeric materials that are used in tracker and fixed tilt systems.
As photovoltaic systems age under relatively harsh and changing environmental conditions, several potential fault conditions can develop during the operational lifetime including corrosion of supporting structures and failures of polymeric materials. The ability to accurately predict the remaining useful life of photovoltaic systems is critical for plants ‘continuous operation. This research contributes to the body of knowledge of PV systems reliability by: (1) developing a meta-model of the expected service life of mounting structures; (2) creating decision frameworks and tools to support practitioners in mitigating risks; (3) and supporting material selection for fielded and future photovoltaic systems. The newly developed frameworks were validated by a global solar company.
As photovoltaic systems age under relatively harsh and changing environmental conditions, several potential fault conditions can develop during the operational lifetime including corrosion of supporting structures and failures of polymeric materials. The ability to accurately predict the remaining useful life of photovoltaic systems is critical for plants ‘continuous operation. This research contributes to the body of knowledge of PV systems reliability by: (1) developing a meta-model of the expected service life of mounting structures; (2) creating decision frameworks and tools to support practitioners in mitigating risks; (3) and supporting material selection for fielded and future photovoltaic systems. The newly developed frameworks were validated by a global solar company.
ContributorsChokor, Abbas (Author) / El Asmar, Mounir (Thesis advisor) / Chong, Oswald (Committee member) / Ernzen, James (Committee member) / Arizona State University (Publisher)
Created2017