Though almost thirty years have passed since the 1991 Tunnel Fire, the wildfire hazard is still present in the Oakland Hills. This study was conducted to determine if the vegetation in the Oakland Hills had reverted back to fuel conditions that contributed to the Tunnel Fire, examine how the fire hazard has changed since 1991, and evaluate planned wildfire mitigation. The goal was to determine how fuel conditions have changed since 1991 and compare potential fire behavior to that of the Tunnel Fire. Additionally, the study examined the effectiveness of the mitigation actions described in the East Bay Regional Park District’s Wildfire Hazard Reduction and Resource Management Plan on lowering extreme fire behavior. Through the use of remote sensing, historical aerial imagery, satellite imagery, and Landsat imagery the 1991 and 2018 fuel conditions were analyzed. ArcGIS Pro and FlamMap 6 were used to compare hectares of fuel and changed in fire behavior between the two year. Mitigation actions were modeled with FlamMap 6 and ArcGIS Pro and fire behavior was compared between untreated conditions and post treatment conditions. The vegetation in the Oakland Hills, in the absence of fire, returned to a mature state, similar to the 1991 conditions. However, there was a reduction in the overall hectares of fuel model 147 in 2018. Modeled fire behavior indicated an overall reduction in extreme fire behavior when comparing 1991 to 2018. This reduction varied on a park level with each park performing differently. When modeled, mitigation was able to lower extreme fire behavior across the landscape but success varied on an individual park basis. In conclusion, should ignition occur presently, under foehn wind conditions, a fire would still exhibit very extreme behavior with a high potential for catastrophic loss, and implantation of planned mitigation measures may be able to lower the degree of extreme fire behavior.

The phenomenon global warming has necessitated the need for a transition towards more environmentally friendly behaviours. One tool amongst many, recognized by the European Commission as effective to fight global warming is energy communities. Västerås municipality’s project team is exploring the opportunity for their new district, Sätra, to operate as an energy community. This report showcases Sätra's economic, social, and technical circumstances, as well as Sweden's regulatory framework. It examines the potential role of local electricity market and smart grid with an energy community. To obtain the results, the methodology included interviews, document analysis, literature reviews, and a feasibility study. The results revealed that the barriers were lack of definition for energy community, lack of awareness among residents, marginalized groups, intermittency of renewable energy sources, and a lack of funding for initiatives. The incentives and mitigation tactics were to create a definition for 'energy communities,' to establish an umbrella organization, raise awareness, and secure funding. The result was compared with the case study of Sätra, and the Västerås municipality’s project team demonstrated utilization of incentives and mitigation strategies in the technical, regulatory, and economic aspects, indicating a likelihood of feasibility. The aspect in which the team did not utilize incentives and mitigation for the barriers was the social aspect. Local electricity markets were not deemed economically practical, but were acknowledged as resilient and efficient in energy distribution. Smart grid’s role in energy communities was, unanimously agreed upon, to be crucial for its features such as cybersecurity, energy efficiency, integration of renewable energy sources, and flexibility.

The response to climate change must include decisive and collaborative solutions that minimize global CO₂ emissions and enable a shift to low-carbon energy (renewable electricity) and CO₂-derived chemicals and fuels. A major challenge of minimizing fossil fuel use is producing critical chemicals and fuels for heavy industry and transportation in novel ways. These traditionally fossil-derived products can be derived from CO₂ that is captured from point sources or the atmosphere. Reactive CO₂ capture is an emerging area of research that focuses on developing materials and processes for CO₂ capture and in situ conversion to valuable chemicals or fuels. By combining these two steps, costly and energy-intensive steps of conventional integrated capture and conversion schemes are eliminated, including sorbent regeneration, CO₂ purification, pressurization, and transportation. These operations typically drive up the cost of capture and conversion processes, making them less economically attractive. The dual function material (DFM) is an Al₂O₃-supported, nano-dispersed catalyst and sorbent combination that demonstrates both capture and catalytic conversion properties, making reactive capture possible. Feasibility of the 1% Ru, 10% “Na₂O”/Al₂O₃ DFM for CO₂ direct air capture (DAC) and in situ catalytic methanation (DACM) has been demonstrated in previous work. Recent work has prioritized advanced laboratory testing and laboratory aging of this DFM under a variety of simulated ambient capture climates to assess the advantages and limitations of the material. A monolith was used as a structured support for the DFM to minimize reactor pressure drop, a particularly relevant challenge for DAC applications where large volumes of air must be processed to separate the small volume of CO₂ (~ 400 ppm). Findings from DFM monolith studies (1% Ru, 10% “Na₂O”/Al₂O₃//monolith) were shared with an engineering partner to support scale up efforts. Laboratory-simulated DACM cycles consisted of DAC performed at various real-world simulated ambient conditions followed by catalytic methanation, where the DFM was heated to 300°C in 15% H₂/N₂. Simulated DAC included O2 and humidity, and a surprising finding showed significant enhancement of CO₂ adsorption due to humidity in the capture feed. The maximum CO₂ capture capacity of the DFM monolith was measured to be 4.4 wt% (based on the weight of DFM material) at 25°C with 2 mol% H₂O in the DAC feed. Aging studies revealed consistent CO₂ capture and CH₄ production after over 450 hours of cyclic DACM testing that included simulated ambient conditions. No signs of deactivation of either the “Na₂O” sorbent or Ru catalyst were observed. The light-off temperature (indicative of kinetic control) observed for catalytic methanation was constant between fresh and aged cycles. These findings verified the qualifications of the 1% Ru, 10% “Na₂O”/Al₂O₃//monolith for the DACM application and supported further advanced bench and pilot plant testing by our engineering collaborator. Additional parametric studies were conducted to evaluate the effects of varying humidity during DAC and revealed that a higher H₂O concentration in the DAC feed correlates with greater CO₂ captured and converted with no evidence of competitive adsorption between CO₂ and H₂O. Additionally, it was found that temperature changes within ambient range (0 – 40°C) played little role in varying CO₂ captured under dry conditions, whereas moisture was found to be a major driver of capture capacity. Furthermore, stable performance at a reference condition was always achieved after excursions to varying ambient conditions. DACM tests revealed 30 – 40% of captured CO₂ desorbs during the temperature swing step, which was attributed mainly to the slow heating rate and low H₂ content (15%) required for safe laboratory operation. Unreacted CO₂ was eliminated by shortening the DAC step and engaging partial capture capacity of the DFM. This mode of cycling is more representative of that which would be carried out at scale, as shorter adsorption durations capitalize on the fastest adsorption kinetics exhibited by a capture material. Consistent with reported literature, findings suggest that CO₂ is preferentially adsorbed to stronger capture sites at the onset of DAC that are better able to retain CO₂ during heat up. Though the DFM is not fully utilized, these partial capacity cycles demonstrated higher conversions to CH₄ and a more efficient use of the material that will require less downstream purification at scale.

Stream ecosystems are increasingly at risk for thermal impairment as urbanization intensifies, resulting in more heated runoff from impervious cover that is less likely to be cooled naturally. While several best management practices, including bioretention filters, have been able to reduce thermal pollution, success has been limited. The extent of thermal mitigation required to prevent ecological damage is unknown. A calibrated runoff temperature model of a case study watershed in Blacksburg, VA was developed to determine the cumulative treatment volume of bioretention filters required to reduce thermal impacts caused by runoff from development in the watershed to biologically acceptable levels. A future build out scenario of the study watershed was also analyzed. Results from this study established that runoff thermal pollution cannot be fully reduced to goal thresholds during all storms using bioretention filter retrofits. While retrofitting significantly decreased temperatures and heat exports relative to the controls, increasing treatment volumes did not really enhance mitigation. Alternate thermal mitigation methods which actively remove runoff volume should be considered where more thermal mitigation is required. / Master of Science / Stream temperature is a significant ecological, biological, and chemical property affecting the long-term health of streams. However, as development intensifies, stream ecosystems are increasingly at risk of being damaged by thermal pollution, which causes warmer and less stable temperatures that distress aquatic organisms. While several stormwater management methods that reduce runoff-related pollution, known as best management practices (BMPs), were found to also decrease thermal pollution, their success has been limited. Furthermore, the extent of thermal mitigation required to prevent ecological damage is unclear. This study aimed to determine how much treatment by a popular BMP, the bioretention filter, was necessary across a watershed in Blacksburg, VA to adequately reduce thermal pollution to protect stream health. Mitigation impacts were tested on both existing and predicted future development conditions through model simulations. Results from this study established that thermal pollution from runoff cannot be fully reduced to goal thresholds consistently using bioretention filter retrofits. While retrofitting significantly decreased thermal pollution, increasing treatment volume did not considerably enhance mitigation. Results suggested that bioretention filters are not an effective method, and alternate thermal mitigation practices which actively remove runoff volume should instead be considered where intensive reductions in thermal pollution are necessary.

Yes / Air pollution has been integrated into global challenges over the last few years due to its negative impact on the health of human beings, increasing socio-economic risks and its contribution to climate change. This study attempts to evaluate the current status of Iran's air pollution with regard to the sources of emissions, control policies, as well as the health and climate consequences that have resulted through available data from monitoring stations reported in the literature, official documents and previous published papers. Many large cities in Iran surpass the permissible concentration of air pollutants, particularly particulate matter, sulfur dioxide, black carbon and ozone. Although regulations and policies are in place and enormous efforts are being made to address air pollution issues in the country, implementation and enforcement are not as effective as they could be. The significant challenges may be regarded as the inefficiency of regulation and supervision systems, the lack of air quality monitoring systems and technology, particularly in industrial cities rather than Tehran as well as the lack of continual feedback and investigations on the efficiency of regulation. Providing such an up-to-date report can bring opportunities for international collaboration, which is essential in addressing the air pollution worldwide. We suggest that a way forward could be more focused on conducting systematic reviews using scientometric methods to show an accurate picture and trend in air pollution and its association in Iran, implementing an integrated approach for both climate change and air pollution issues, collaborating with international counterparts to share knowledge, tools, and techniques.

This study proposes a framework and a process promoting creation of sustainable jobs and businesses in rural, arid and semi-arid agricultural conflict zones of Sub Saharan Africa, focusing on Somalia's societal stabilization and conflict mitigation. This task requires developing risk-reducing measures for infrastructure and service delivery in rural, post-conflict zones. Literature reviews identified two economic growth theories rooted in sustainability concepts for localized, pro-poor development. Ecological Economics Theory (EET) and Endogenous Growth Theory (EGT) are the philosophical bases establishing investment priorities. Additional research regarding Somali culture, key conflict factors, and potential business opportunities, provides an understanding of salient facts in Somalia's on-going, 27-years of war and potential culturally acceptable development pathways. Informal sources, Somali and non-Somali, were consulted to further identify and verify potential avenues for economic growth, sustainability, educational opportunities, allowing Somalia to emerge from the strife it has endured. Visits to Somalia and Somaliland confirmed that livestock, its products and related requirements, are key components for economic growth and job creation. Investigation, via pilot testing and case studies, was undertaken of technologies with potential to improve productive capacity and disrupt existing value chains. Initial framework elements were evaluated for job and business creation, through unstructured, semi-structured interviews, and questionnaire of Somali officials, and Somali and non-Somali conflict zone development practitioners. The pilot test used a small sample size and is a limitation of this work. Findings from the literature review, informal discussions, and the pilot test are synthesized into the framework presented in Chapter 5. The framework proposes development of an innovative, disruptive, and scalable business model that facilitates the simultaneous implementation of renewable energy production. It targets education for the livestock and agroforestry industry of Somalia, improving job and business opportunities. The model proposes modification of used shipping containers for the creation of modular elements, to satisfying infrastructural building components to initiate skills practice, job, and business growth. / Doctor of Philosophy / The wars and conflicts of various types in Africa have made the continent poorer and prevented development in many countries. One of the major, and seemingly intractable conflict locations, is Somalia located in the East Horn of Africa (EHA). This research provides an understanding of salient facts in Somalia's 27 years of war by examining culture and key conflict factors. The objective of this assessment is to identify potential culturally acceptable pathways that will lead to business opportunities and development as a means of conflict mitigation. The improvement of job opportunities for youth is viewed as a means to offset the current participation in the ongoing conflict. Somali and non-Somali sources were consulted to identify and verify avenues for economic growth, sustainability, and educational opportunities. Visits to Somalia and Somaliland confirmed that livestock, and related products, are key components for development and job creation. Technologies with potential to improve productive capacity and disrupt existing value chains were also evaluated. Findings from informal discussions and a pilot test of a proposed framework are presented. The framework identifies elements for development of an innovative, disruptive, and scalable business model that facilitates the implementation of renewable energy production. In addition, it targets education for the livestock and agroforestry industries, improving job and business opportunities.

<p>In sum, these studies described in this dissertation showed that both mycotoxin deoxynivalenol exposure and nutrient starvation can increase endocytosis and degradation of tight junction proteins in the lysosome. Therefore, manipulation of endocytic pathway as well as the signaling pathway involved in this process can be used to prevent intestinal barrier dysfunction in animals.</p> <p><br></p>

This study aims to empirically explore if there is an association between climate-related disasters and climate mitigation policy change in middle-income countries. This is important for understanding future climate mitigation policy, as disasters are predicted to increase in both frequency and severity. I explore this by studying climate mitigation policy activity change among countries in Latin America and the Caribbean. The region is chosen due to a lack of previous studies in both the region specifically, as well as in middle-income countries generally. Due to uncertainties in the exact time lag between the disaster and policy response, different methods are used: one 5-year normalized scatterplot and two fixed effects (FE) regressions with 1- and 2-year time lags respectively. The results show no statistically significant effects between the variables when looking at a 1-year FE regression or a 5-year normalized scatterplot, however, it does find a negative correlation between extreme-impact events and affected people when using a 2-year FE regression. A possible interpretation of the results is that severe climate-related disasters pause climate mitigation policy development, but not the process of the policies already developed pre-disaster and that these are short-term effects. However, further studies are needed to confirm this.

This dissertation presents a novel technique called duplicate with choose (DWCh) which is a modification of the fault detection technique duplicate with compare (DWC). DWCh adds a smart decider block to DWC that monitors the duplicated circuits and decides which circuit is fault free when a fault occurs. If chosen correctly, DWCh is able to mask faults at a lower cost than conventional techniques like TMR.This dissertation derives reliability expressions for DWCh showing that under ideal conditions its reliability exceeds the most commonly used fault masking technique for spacecraft, triple modular redundancy. For non-ideal conditions, DWCh provides a lower cost alternative than TMR but with lower reliability as well. Three types of DWCh smart deciders were developed for use with digital communications receivers. The first type used histograms as the statistical basis for the decider. The second type made use of moments for decision. The third type, although not generally applicable to other systems, used a signal common to communications receivers with excellent results. The communications receivers were subjected to hardware fault injection to gather datastreams affected by real world faults. The captured datastreams were used with Simulink models of the different deciders to quantify their performance and discover how a practical implementation of DWCh differs from the theoretical model. The increase in mean time to failure for DWCh when compared to simplex ranged from 20x to 130x depending on the specific smart decider tested.

Radio Astronomy, the study of distant objects in the radio spectrum, is set at defiance against all other users of the electromagnetic spectrum. Where traditional use would fill the electromagnetic spectrum with as much transmission and information as possible, Radio Astronomy would rather no man-made signals existed. Since that is not possible, they grumble and have to deal with unwanted transmissions impinging upon their instruments. I have demonstrated that subspace projection can remove these unwanted signals from Radio Astronomical data in post processing. I demonstrate it both on simulated data and on data taken from the Very Large Array radio telescope.In the process of implementing the algorithm, I show that the self power terms contain necessary information about the array element responses to RFI sources. While the autocorrelation are not used in the normal synthesis imaging process, my work shows that RFI mitigation using Subspace Projection performs better with the autocorrelations retained when computing projection matrices. Furthermore, I demonstrate that proper data collection allows a significant decrease in error under subspace projection. Potential enhancements to subspace projection are also briefly considered.