Matching Items (8)
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- All Subjects: Sustainability
- Genre: Academic theses
- Status: Published
Description
Random Forests is a statistical learning method which has been proposed for propensity score estimation models that involve complex interactions, nonlinear relationships, or both of the covariates. In this dissertation I conducted a simulation study to examine the effects of three Random Forests model specifications in propensity score analysis. The results suggested that, depending on the nature of data, optimal specification of (1) decision rules to select the covariate and its split value in a Classification Tree, (2) the number of covariates randomly sampled for selection, and (3) methods of estimating Random Forests propensity scores could potentially produce an unbiased average treatment effect estimate after propensity scores weighting by the odds adjustment. Compared to the logistic regression estimation model using the true propensity score model, Random Forests had an additional advantage in producing unbiased estimated standard error and correct statistical inference of the average treatment effect. The relationship between the balance on the covariates' means and the bias of average treatment effect estimate was examined both within and between conditions of the simulation. Within conditions, across repeated samples there was no noticeable correlation between the covariates' mean differences and the magnitude of bias of average treatment effect estimate for the covariates that were imbalanced before adjustment. Between conditions, small mean differences of covariates after propensity score adjustment were not sensitive enough to identify the optimal Random Forests model specification for propensity score analysis.
ContributorsCham, Hei Ning (Author) / Tein, Jenn-Yun (Thesis advisor) / Enders, Stephen G (Thesis advisor) / Enders, Craig K. (Committee member) / Mackinnon, David P (Committee member) / Arizona State University (Publisher)
Created2013
Description
Owner organizations in the architecture, engineering, and construction (AEC) industry are presented with a wide variety of project delivery approaches. Implementation of these approaches, while enticing due to their potential to save money, reduce schedule delays, or improve quality, is extremely difficult to accomplish and requires a concerted change management effort. Research in the field of organizational behavior cautions that perhaps more than half of all organizational change efforts fail to accomplish their intended objectives. This study utilizes an action research approach to analyze change message delivery within owner organizations, model owner project team readiness and adoption of change, and identify the most frequently encountered types of resistance from lead project members. The analysis methodology included Spearman's rank order correlation, variable selection testing via three methods of hierarchical linear regression, relative weight analysis, and one-way ANOVA. Key findings from this study include recommendations for communicating the change message within owner organizations, empirical validation of critical predictors for change readiness and change adoption among project teams, and identification of the most frequently encountered resistive behaviors within change implementation in the AEC industry. A key contribution of this research is the recommendation of change management strategies for use by change practitioners.
ContributorsLines, Brian (Author) / Sullivan, Kenneth (Thesis advisor) / Wiezel, Avi (Committee member) / Badger, William (Committee member) / Arizona State University (Publisher)
Created2014
Description
The United States building sector was the most significant carbon emission contributor (over 40%). The United States government is trying to decrease carbon emissions by enacting policies, but emissions increased by approximately 7 percent in the U.S. between 1990 and 2013. To reduce emissions, investigating the factors affecting carbon emissions should be a priority. Therefore, in this dissertation, this research examine the relationship between carbon emissions and the factors affecting them from macro and micro perspectives. From a macroscopic perspective, the relationship between carbon dioxide, energy resource consumption, energy prices, GDP (gross domestic product), waste generation, and recycling waste generation in the building and waste sectors has been verified. From a microscopic perspective, the impact of non-permanent electric appliances and stationary and non-stationary occupancy has been investigated. To verify the relationships, various kinds of statistical and data mining techniques were applied, such as the Granger causality test, linear and logarithmic correlation, and regression method. The results show that natural gas and electricity prices are higher than others, as coal impacts their consumption, and electricity and coal consumption were found to cause significant carbon emissions. Also, waste generation and recycling significantly increase and decrease emissions from the waste sector, respectively. Moreover, non-permanent appliances such as desktop computers and monitors consume a lot of electricity, and significant energy saving potential has been shown. Lastly, a linear relationship exists between buildings’ electricity use and total occupancy, but no significant relationship exists between occupancy and thermal loads, such as cooling and heating loads. These findings will potentially provide policymakers with a better understanding of and insights into carbon emission manipulation in the building sector.
ContributorsLee, Seungtaek (Author) / Chong, Oswald (Thesis advisor) / Sullivan, Kenneth (Committee member) / Tang, Pingbo (Committee member) / Arizona State University (Publisher)
Created2018
Description
For decades, load shifting control, one of the most effective peak demand management methods, has attracted attention from both researchers and engineers. Various load shifting controls have been developed and introduced in mainly commercial buildings. Utility companies typically penalize consumers with “demand rates”. This along with increased population and increased customer energy demand will only increase the need for load shifting. There have been many white papers, thesis papers and case studies written on the different types of Thermal Energy Storage and their uses. Previous papers have been written by Engineers, Manufacturers and Researchers. This thesis paper is unique because it will be presented from the application and applied perspective of the Facilities Manager. There is a need in the field of Facilities Management for relevant applications. This paper will present and discuss the methodology, process applications and challenges of load shifting using (TES) Thermal Energy Storage, mainly ice storage.
ContributorsWhitcraft, Daniel S (Author) / Sullivan, Kenneth (Thesis advisor) / Okamura, Patrick (Committee member) / Slife, Curtis (Committee member) / Arizona State University (Publisher)
Created2016
Description
With increasing interest in sustainability and green building, organizations are implementing programs such as Leadership in Energy and Environmental Design for Existing Buildings: Operations and Maintenance (LEED-EB) in order to focus corporate sustainability goals on the operations of a facility and the practices of the building occupants. Green building programs help reduce the impact of a facility and bring about several environmental benefits including but not limited to energy conservation, water conservation and material conservation. In addition to various environmental benefits, green building programs can help companies become more efficient. The problem is that organizations are not always successful in their pursuits to achieve sustainability goals. It frequently take years to implement a program, and in many cases the goals for sustainability never come to fruition, when in the mean time resources are wasted, money is spent needlessly and opportunities are lost forever. This thesis addresses how the Six Sigma methodologies used by so many to implement change in their organizations could be applied to the LEED-EB program to help companies achieve sustainability results. A qualitative analysis of the Six Sigma methodologies was performed to determine if and how a LEED-EB program might utilize such methods. The two programs were found to be compatible and several areas for improvements to implementing a LEED-EB program were identified.
ContributorsFurphy, Kimberly (Author) / Hild, Nicholas (Thesis advisor) / Olson, Larry (Committee member) / Sullivan, Kenneth (Committee member) / Arizona State University (Publisher)
Created2010
Description
In recent years, many school districts, community colleges, and universities in California have implemented energy management-as-a-service (EMaaS). The purpose of this study was to analyzes how EMaaS has been realized in California schools, including how performance expectations and service guarantees have been met, how value is created and captured, and which trends are emerging in the pay-for-performance models. This study used a qualitative research design to identify patterns in the collected data and allow theories to be drawn from the emergent categories and themes. Ten in-depth interviews were conducted with a diverse pool of facility managers, energy practitioners, superintendents, and associate superintendents working with EMaaS. Four themes emerged (1) peak shaving overperformance, (2) low risk/reward, (3) performance exactly as expected, and (4) hope in future flexibility. This study reveals medium to high levels of performance satisfaction from the customers of cloud-enabled and battery-based EMaaS in California schools. Value has been captured primarily through peak shaving and intelligent bill management. Large campuses with higher peaks are especially good at delivering energy savings, and in some instances without pairing batteries and solar. Where demand response participation is permitted by the utility companies, the quality of demand response performance is mixed, with performance being exactly as expected to slightly less than expected. The EMaaS business model is positioned to help California schools implement and achieve many of their future sustainability goals in a cost-effective way.
ContributorsHawkins, Spencer (Author) / Sullivan, Kenneth (Thesis advisor) / Parrish, Kristen (Thesis advisor) / Standage, Richard (Committee member) / Arizona State University (Publisher)
Created2020
Description
Although Saudi Arabia is moving towards a sustainable future, Existing residential buildings in the country are extremely unsustainable. Therefore, there is a necessity for greening the existing residential building. Mostadam green rating systems was developed by the Saudi ministry of housing in 2019 to address the long-term sustainability vision in residential buildings in the country. By setting Mostadam requirements as an objective of the retrofit process, it will ensure that the building achieve sustainability. However, Mostadam is new and there is a lack of knowledge of implementing its requirements on existing buildings. The aim of this research is to develop a framework to green existing residential buildings in Saudi Arabia to achieve Mostadam energy and water minimum requirements. The framework was developed based on an extensive keyword-based search and an analysis of 92 relevant research. The process starts with assessing the building against the minimum requirements of energy and water of Mostadam. After that, optimization phase is conducted. Building information modelling is used in the optimization phase. Energy and water efficiency optimization measures are identified from the analysed literature. Revit is used in the base model authoring and Green building studio cloud is used to simulate the energy and water efficiency measures. Then, payback period is calculated for all the efficiency measured to assess the decision making. A case study of a villa in Riyadh, Saudi Arabia is provided. result shows that the implemented efficiency measures led to an increment of 37.5% in annual energy savings and 26.1% in the annual water savings. Results shows that the application of the proposed framework supports evaluating energy and water efficiency measures to implement it on the buildings to achieve Mostadam minimum energy and water requirements. Recommendations were made for future work to bridge the knowledge gap.
ContributorsMohamed, Sara Murad (Author) / Sullivan, Kenneth (Thesis advisor) / Chong, Oswald (Committee member) / Hurtado, Kristen (Committee member) / Arizona State University (Publisher)
Created2022
Description
The intent of this study was to identify the most viable among a proposive sample of emerging sustainable construction technologies with respect to the Twin Cities Metropolitan Geographic Area. With space heating and space cooling accounting for such a significant portion of energy consumption in Twin Cities homes, a representative sample of homes was analyzed for annual heating and cooling loads. For each home a series of heating, ventilation, air conditioning (HVAC) and envelope equipment was modeled in order to provide data for various sustainable home construction technologies. The result was a specific amount of energy savings from baseline construction methods for each sustainable technology. The study found that integrated geothermal heat pump and radiant conditioning systems have a far greater impact on energy savings than the construction methods evaluated. Nevertheless, insulated concrete forms provided the greatest energy savings within the proposive set of construction methods. The greatest amount of space conditioning energy savings of all configurations tested was 73.48% using an integrated geothermal heat pump and radiant conditioning system, structural insulated panel wall construction, aerosol air infiltration prevention, and insulated concrete form basement construction. The results of the study were used to determine areas for further research and to provide awareness within the Twin Cities construction enterprise to determine the most viable technologies that contractors, municipalities, and citizens should prioritize moving forward.
ContributorsMcKilligan, Ryan (Author) / Sullivan, Kenneth (Thesis advisor) / Stone, Brian (Committee member) / Smithwick, Jake (Committee member) / Arizona State University (Publisher)
Created2019