Matching Items (26)
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Description
In developed countries, municipalities deliver drinking water to constituents through water distribution systems. These transport water from a treatment plant to homes, restaurants, and any other site of end use. Proper water distribution system infrastructure functionality is a critical concern to city planners and managers because component failures within these

In developed countries, municipalities deliver drinking water to constituents through water distribution systems. These transport water from a treatment plant to homes, restaurants, and any other site of end use. Proper water distribution system infrastructure functionality is a critical concern to city planners and managers because component failures within these systems restrict or prevent the ability to deliver water. The reduced capacity to deliver water forces the health and well being of all citizens into jeopardy. The breakdown of a component can even spark the failure of several more components, causing a sequence of cascading failures with catastrophic consequences. To make matters worse, some forms of component failures are unpredictable and it is impossible to foresee every possible failure that could occur. In order to prevent cataclysmic losses that are experienced during system failures, the development of resilient water distribution infrastructure is vital. A resilient water distribution system possesses an adaptive capacity to mitigate the loss of service resulting from component failures. Traditionally, infrastructure resilience research has been retrospective in nature, analyzing the infrastructure system after it suffered a failure event. However, this research project takes water distribution resilience research in a new direction. The research identifies the Sensing Anticipating, Adaptation, and Learning processes that are inherent in the current operations of each component in the water distribution system (pumps, pipes, valves, tanks, nodes). Additional SAAL processes have been recommended for the components that lack adaptive management in current practice. This workis unique in that it applies resilience theory to water distribution systems in an anticipatory manner. This anticipatory application of resilience will provide operators with actionable process for them to implement during failure situations. In this setting, resilience is applied to existing systems for noticeable improvements in operation during failure situations.
ContributorsRodriguez, Jordan Robert (Author) / Seager, Thomas (Thesis director) / Eisenberg, Daniel (Committee member) / Bondank, Emily (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description

Heat vulnerability of urban populations is becoming a major issue of concern with climate change, particularly in the cities of the Southwest United States. In this article we discuss the importance of understanding coupled social and technical systems, how they constitute one another, and how they form the conditions and

Heat vulnerability of urban populations is becoming a major issue of concern with climate change, particularly in the cities of the Southwest United States. In this article we discuss the importance of understanding coupled social and technical systems, how they constitute one another, and how they form the conditions and circumstances in which people experience heat. We discuss the particular situation of Los Angeles and Maricopa Counties, their urban form and the electric grid. We show how vulnerable populations are created by virtue of the age and construction of buildings, the morphology of roads and distribution of buildings on the landscape. Further, the regulatory infrastructure of electricity generation and distribution also contributes to creating differential vulnerability. We contribute to a better understanding of the importance of sociotechnical systems. Social infrastructure includes codes, conventions, rules and regulations; technical systems are the hard systems of pipes, wires, buildings, roads, and power plants. These interact to create lock-in that is an obstacle to addressing issues such as urban heat stress in a novel and equitable manner.

Created2016-08-25
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Description

The leading source of weather-related deaths in the United States is heat, and future projections show that the frequency, duration, and intensity of heat events will increase in the Southwest. Presently, there is a dearth of knowledge about how infrastructure may perform during heat waves or could contribute to social

The leading source of weather-related deaths in the United States is heat, and future projections show that the frequency, duration, and intensity of heat events will increase in the Southwest. Presently, there is a dearth of knowledge about how infrastructure may perform during heat waves or could contribute to social vulnerability. To understand how buildings perform in heat and potentially stress people, indoor air temperature changes when air conditioning is inaccessible are modeled for building archetypes in Los Angeles, California, and Phoenix, Arizona, when air conditioning is inaccessible is estimated.

An energy simulation model is used to estimate how quickly indoor air temperature changes when building archetypes are exposed to extreme heat. Building age and geometry (which together determine the building envelope material composition) are found to be the strongest indicators of thermal envelope performance. Older neighborhoods in Los Angeles and Phoenix (often more centrally located in the metropolitan areas) are found to contain the buildings whose interiors warm the fastest, raising particular concern because these regions are also forecast to experience temperature increases. To combat infrastructure vulnerability and provide heat refuge for residents, incentives should be adopted to strategically retrofit buildings where both socially vulnerable populations reside and increasing temperatures are forecast.

ContributorsNahlik, Matthew J. (Author) / Chester, Mikhail Vin (Author) / Pincetl, Stephanie Sabine, 1952- (Author) / Eisenman, David (Author) / Sivaraman, Deepak (Author) / English, Paul (Author)
Created2016-11-11
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Description

In an extreme heat event, people can go to air-conditioned public facilities if residential air-conditioning is not available. Residences that heat slowly may also mitigate health effects, particularly in neighborhoods with social vulnerability. We explored the contributions of social vulnerability and these infrastructures to heat mortality in Maricopa County and

In an extreme heat event, people can go to air-conditioned public facilities if residential air-conditioning is not available. Residences that heat slowly may also mitigate health effects, particularly in neighborhoods with social vulnerability. We explored the contributions of social vulnerability and these infrastructures to heat mortality in Maricopa County and whether these relationships are sensitive to temperature. Using Poisson regression modeling with heat-related mortality as the outcome, we assessed the interaction of increasing temperature with social vulnerability, access to publicly available air conditioned space, home air conditioning and the thermal properties of residences. As temperatures increase, mortality from heat-related illness increases less in census tracts with more publicly accessible cooled spaces. Mortality from all internal causes of death did not have this association. Building thermal protection was not associated with mortality. Social vulnerability was still associated with mortality after adjusting for the infrastructure variables. To reduce heat-related mortality, the use of public cooled spaces might be expanded to target the most vulnerable.

ContributorsEisenman, David P. (Author) / Wilhalme, Holly (Author) / Tseng, Chi-Hong (Author) / Chester, Mikhail Vin (Author) / English, Paul (Author) / Pincetl, Stephanie Sabine, 1952- (Author) / Fraser, Andrew (Author) / Vangala, Sitaram (Author) / Dhaliwal, Satvinder K. (Author)
Created2016-08-03
Description

As average temperatures and occurrences of extreme heat events increase in the Southwest, the water infrastructure that was designed to operate under historical temperature ranges may become increasingly vulnerable to component and operational failures. For each major component along the life cycle of water in an urban water infrastructural system,

As average temperatures and occurrences of extreme heat events increase in the Southwest, the water infrastructure that was designed to operate under historical temperature ranges may become increasingly vulnerable to component and operational failures. For each major component along the life cycle of water in an urban water infrastructural system, potential failure events and their semi-quantitative probabilities of occurrence were estimated from interview responses of water industry professionals. These failure events were used to populate event trees to determine the potential pathways to cascading failures in the system. The probabilities of the cascading failure scenarios under future conditions were then calculated and compared to the probabilities of scenarios under current conditions to assess the increased vulnerability of the system. We find that extreme heat events can increase the vulnerability of water systems significantly and that there are ways for water infrastructure managers to proactively mitigate these vulnerabilities before problems occur.

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Description

The leading source of weather-related deaths in the United States is heat, and future projections show that the frequency, duration, and intensity of heat events will increase in the Southwest. Presently, there is a dearth of knowledge about how infrastructure may perform during heat waves or could contribute to social

The leading source of weather-related deaths in the United States is heat, and future projections show that the frequency, duration, and intensity of heat events will increase in the Southwest. Presently, there is a dearth of knowledge about how infrastructure may perform during heat waves or could contribute to social vulnerability. To understand how buildings perform in heat and potentially stress people, indoor air temperature changes when air conditioning is inaccessible are modeled for building archetypes in Los Angeles, California, and Phoenix, Arizona, when air conditioning is inaccessible is estimated.

An energy simulation model is used to estimate how quickly indoor air temperature changes when building archetypes are exposed to extreme heat. Building age and geometry (which together determine the building envelope material composition) are found to be the strongest indicators of thermal envelope performance. Older neighborhoods in Los Angeles and Phoenix (often more centrally located in the metropolitan areas) are found to contain the buildings whose interiors warm the fastest, raising particular concern because these regions are also forecast to experience temperature increases. To combat infrastructure vulnerability and provide heat refuge for residents, incentives should be adopted to strategically retrofit buildings where both socially vulnerable populations reside and increasing temperatures are forecast.

Created2015
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Description

Access to air conditioned space is critical for protecting urban populations from the adverse effects of heat exposure. Yet there remains fairly limited knowledge of penetration of private (home air conditioning) and distribution of public (cooling centers and commercial space) cooled space across cities. Furthermore, the deployment of government-sponsored cooling

Access to air conditioned space is critical for protecting urban populations from the adverse effects of heat exposure. Yet there remains fairly limited knowledge of penetration of private (home air conditioning) and distribution of public (cooling centers and commercial space) cooled space across cities. Furthermore, the deployment of government-sponsored cooling centers is not based on the location of existing cooling resources (residential air conditioning and air conditioned public space), raising questions of the equitability of access to heat refuges.

Using Los Angeles County, California and Maricopa County, Arizona (whose county seat is Phoenix) we explore the distribution of private and public cooling resources and access inequities at the household level. We do this by evaluating the presence of in-home air conditioning and developing a walking-based accessibility measure to air conditioned public space using a combined cumulative opportunities-gravity approach. We find significant inequities in the distribution of residential air conditioning across both regions which are largely attributable to building age and inter/intra-regional climate differences. There are also regional disparities in walkable access to public cooled space.

At average walking speeds, we find that official cooling centers are only accessible to a small fraction of households (3% in Los Angeles, 2% in Maricopa) while a significantly higher number of households (80% in Los Angeles, 39% in Maricopa) have access to at least one other type of public cooling resource which includes libraries and commercial establishments. Aggregated to a neighborhood level, we find that there are areas within each region where access to cooled space (either public or private) is limited which may increase the health risks associated with heat.

Created2016
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Description

As of May 2022, there have been more than 80 million confirmed cases of COVID-19 across the United States, and over two million cases in Arizona. The pandemic has had a devastating impact on local, national, and global economies. This brief features the findings from data collected from a survey

As of May 2022, there have been more than 80 million confirmed cases of COVID-19 across the United States, and over two million cases in Arizona. The pandemic has had a devastating impact on local, national, and global economies. This brief features the findings from data collected from a survey administered to Arizona residents in April of 2021, as well as national statistics, to understand some of the economic consequences of COVID-19 and its impacts on Arizona households.

Created2022-06-01