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A data-driven approach for the evaluation of seismicity risks associated with CO2 injection
Get PDFThis work examined the application of Bayes’ theorem in evaluating the risk of induced seismicity associated with CO2 sequestration in the Arbuckle Group, which extends across the southern Mid-Continent of the US. Geological storage can effectively contribute to reducing emission of CO2, otherwise released into the atmosphere, achieving the climate goals committed in the 2021 United Nations Climate Change Conference (COP26). However, concerns about risks associated with CO2 injection along with economic challenges of infrastructure required to execute the Carbon Capture Utilization and Storage projects stand against full realization of remarkable potentials. The main goal is usually for CO2 to be stored over geologic time; hence, geomechanical risks such as the seismicity in the field or potential CO2 leakage through seals cannot be ignored and is considered as one of the requirements to determine success of the project.
This work elaborated on the risk of potential seismic events that can impact the longevity and success of projects. Accurate risk estimation is key for environmental, economic, and safety concerns and is also one of the requirements to get class VI permits from the US Environmental Protection Agency. The increase of fluid injection in the Arbuckle Group and how it has increased seismicity risks was first demonstrated, and then utilizing the Bayesian approach, a statistical model where a random probability distribution is used to represent uncertainties within the model, including both input/output parameters to evaluate the seismicity risks was used to estimate these risks. Using the Arbuckle Group as a case study, established physics-based models of the system and the details from past observed/monitored failures was utilized to evaluate future risk potential for the area. In this approach, the current probability for the state of stress for the area under investigation was established, then the evolution in the state of stress was monitored. The stress state probability distribution was calculated to evaluate the probability of activating a critically oriented fault over a range of specified pore pressures.
The results suggest seismicity risk is directly a function of fluid injection and that the probability of inducing seismicity in the formation can be estimated. Based on the modelling results, at initial injection pressures there is a 24% risk of introducing seismicity in the Arbuckle Group when a critically oriented fault exists. Based on these results, sensitivity analysis was conducted to determine the features that can impact the risk level. Introducing the stress state constraints from the Arbuckle Group in Kansas State, the risk of seismicity reduced to 12%.
Considering the results from this work, operators can optimize the site screening and collect additional data to constrain inherent uncertainties in geomechanical risk evaluation and make informed decisions during operations. The result from this work shows that geological storage of CO2 with attention to seismicity risks in the Arbuckle formation can be a feasible safe strategy towards achieving climate goals in selected areas and there is value of information in obtaining stress data in these areas
Development of Envelope Evaluation Benchmarks Using EnergyPlus and Data-Driven Thermal Model
Get PDFResidential buildings account for a large portion of the consumption of the global energy and total energy by end use. To mitigate the rising trend of energy consumption, residential buildings show a huge potential by improving their energy efficiencies, thus achieving energy saving. Moreover, the envelopes of the residential building, as one of key factors in the energy consumption of a building, are closely related to building energy saving, as it closely determines how much heat is transferred between indoor space of the building and its outdoor environment. Even though the challenges in how to judge the performance of the residential envelopes, especially evaluation of the overall building envelope via model-based data-driven and measurement-based methods, have been addressed by current studies and still have their limitations in comparison with ground truth, a method to benchmark the envelope performance evaluation is still lacking and urgently needed. Therefore, a benchmarking method using both building energy and thermal network models is proposed in this study.
Specifically, this study first proposes a calibration method that utilizes both EnergyPlus and simplified 2R2C models. The EnergyPlus models are used to generate simulated data that are utilized in the simplified 2R2C model training. Moreover, this study also creates an excel dashboard, along with the the EnergyPlus and simplified 2R2C models, for the calibration process. Then three representative years of American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) standards are selected to the minimum thermal property requirement of residential building envelope and utilized in the calibrated EnergyPlus models. In the next step, a benchmarking method is proposed to determine the minimum required Tau value (time constant of building envelope) for a specific year of a residential building envelope. That is, different years of houses need to meet the minimum thermal property requirement of residential building envelope defined by ASHRAE standards. Lastly, the performance evaluation benchmarking process can be done with the determination of thermal properties identified by the simplified 2R2C model trained using simulated data from the calibrated EnergyPlus model.
Overall, this research successfully proposes an efficient calibration method to calibrate EnergyPlus modes used for residential buildings, introduces quantitative study and performance analysis of a calibration method that utilizes building thermal network models, and develops a benchmark method and shows investigation and analysis for building envelope performance evaluation. Therefore, this research contributes the knowledge of benchmarking the envelope performance evaluation using both EnergyPlus and data-driven thermal model for residential buildings
Design and setup of an Atom Interferometer Gyroscope using a strontium thermal beam
Get PDFA gyroscope was developed and demonstrated using strontium atom interferometry on a rotating platform. This will allow us to study the interplay of the Atomic Interferometer Gyroscope (AIG) physics with large rotation rates. This apparatus, not tested yet, is very promising because the proof-of-concept experiment for the new strontium interferometer used by the gyroscope gave us good results and there are many improvements to be explored such as Large Momentum Transfer (LMT). The applications for this apparatus can be inertial navigation and geophysical studies. The principle of operation is as follows: A thermal strontium atomic beam crosses three laser interaction regions where resonant beams stimulate transitions between strontium ground states and excited states. With this transition, these beams transfer momentum to atoms that divide, deflect and recombine the atomic wavepackets. A rotation induced phase shift between the two arms of the gyroscope causes a change in the detected number of atoms with a particular internal state. The rotations phase shifts are proportional to the vector velocity of the atoms. Furthermore, rotation Doppler-shifts the π and π/2 beams
Design and Implementation of a Novel Multicopter Unmanned Aircraft System for Quantitative Studies of the Atmosphere
Get PDFThe call for creating new innovative meteorological instruments to help fulfill observational gaps in the atmospheric sciences has been gaining strength in the past few years. This comes along with the urgent need to increase the understanding of fast-evolving atmospheric processes to subsequently provide accurate and reliable weather forecasts in a timely manner. The increased interest in obtaining atmospheric observations with higher spatio-temporal resolution pushed scientists to begin exploring and harnessing new leading-edge engineering technology. For instance, affordable and accessible Unmanned Aircraft Systems (UASs) technology emerged within this timeframe and has since evolved rapidly. Many researchers and institutions have agreed that UASs are promising technology candidates for targeted in situ weather sampling, which has the potential to meet the stringent meteorological measurement requirements. However, the current market has shifted and shaped UASs for other applications that may be unsuitable or suboptimal for weather sampling. Special considerations were examined in this study to conceptualize a specialized weather UAS (WxUAS) capable of collecting reliable thermodynamic and kinematic measurements. While also performing similarly to conventional weather instruments, such as radiosondes, Doppler wind lidars, and meteorological towers, as well as providing a complementary role whenever measurement limitations arise.
Therefore, given that the exploration of integrating weather instrumentation into UAS is rare, it is hypothesized that atmospheric measurements of a modified multicopter UAS that minimizes platform-induced errors can fill the thermodynamic and kinematic data gap in the planetary boundary layer (PBL). The proposed solution is a UAS-based in situ vertical profiler system, dubbed the CopterSonde, with necessary weather instrumentation, adequate sensor placement, and useful flight functions for optimal sampling of undisturbed air. This solution attempts to provide a holistic WxUAS design where the UAS itself was adapted to become not just a payload carrier but also part of the weather instrumentation system. Flow simulation studies backed with observations in the field were used to address sensor siting and mitigate sources of thermodynamic errors. Moreover, techniques for thermodynamic measurement correction, adaptable flight behavior, and 3D wind estimation were implemented using the experimental CopterSonde concept with results comparable to widely accepted conventional weather instruments. Additionally, the platform reliability was successfully demonstrated in different challenging environments, from freezing temperatures in Hailuoto, Finland, to high elevations in Colorado, USA. A robust concept of operation and decision-making algorithms were established to ensure safe flights during demanding field campaigns. As a result, the National Oceanic and Atmospheric Administration (NOAA) in the USA has recognized the CopterSonde as part of the approved UAS fleet for NOAA-related missions.
Overall, the engineering advances shown in this work helped to produce an optimized UAS capable of collecting targeted and reliable weather observations. Even though the CopterSonde is an experimental design, this work can be used as a guideline to define future standards for WxUAS development and deployment
Ecosystem Structural and Functional Indicators to Evaluate Conservation Easement Success in the Horse Creek Watershed near the Grand Lake o' the Cherokees, Oklahoma
No full textStream restoration activities in the United States commonly seek to improve aquatic and riparian structure. Traditional assessment methods evaluate ecosystem structure by estimating metrics such as biotic community assemblages, stream flow regimes, and riparian vegetation. However, very few assessments incorporate measures of ecosystem function, such as decomposition and productivity. In the Horse Creek watershed near the Grand Lake o’ the Cherokees in northeastern Oklahoma, stream restoration efforts take the form of cattle exclusion fences to address impaired stream habitat and water quality, and to decrease stress from livestock grazing on riparian vegetation. This study seeks to assess the impact of these conservation easements on ecosystem structure and function. Three sites were selected in the Horse Creek watershed, one within the conservation easement area and two outside of the exclusion fences. A reference stream, Fivemile Creek, was identified in the region for comparison. A geographic information system (GIS) evaluation of land use and land cover in the watersheds highlights a great degree of agricultural land use in the Horse Creek watershed, and a lesser anthropogenic impact in the Fivemile Creek watershed. Habitat assessments indicated that overall structural habitat quality was greatest at the reference site, lower in the conservation easement treatment site, and were the lowest at the two control sites. Fish and macroinvertebrate results indicate the greatest scores for biotic indices at the reference stream, followed by the conservation reach at Horse Creek, then the control reach. A remote sensing study of the watershed indicated that Normalized Difference Vegetation Index (NDVI) values increased during a two-year time interval in two of the three fenced-in conservation easement reaches, and aboveground biomass increased in all three fenced-in reaches. Ecosystem function was evaluated by estimating productivity and respiration through diel dissolved oxygen changes, and a cotton strip assay was conducted to evaluate rates of decomposition. Net primary productivity did not correlate to water quality, habitat metrics, or land use. Decomposition rates were lowest in the reference stream, were greater in the conservation easement site, and were greatest outside of the conservation easements. Results of metabolism and decomposition studies were treated as dependent variables and compared to physicochemical water quality parameters, watershed land use, and habitat metrics. These results support the use of cattle exclusion conservation easements to improve impaired water and habitat quality in the Horse Creek watershed
Scalable Multipartite Entanglement Using Squeezed light
Get PDFQuantum entanglement is a pure quantum mechanical phenomena with no classical counterpart. The strong non locality of multipartite entangled states makes it suitable for application of quantum mechanics towards quantum computing, quantum key distribution and quantum interferometry. Many methods have been proposed for the generation of scalable multipartite entangled states in the frequency domain and by time-bin multiplexing. However, these are not suitable for long distance quantum communication. To build a long distance quantum network, we need a spatially separable multipartite entangled system. In this thesis, we focus on the use of a quantum interferometer, known as the SU(1,1) interferometer formed using a two mode squeezed quantum state, to generate a multipartite entangled quantum system in the spatial domain.
We start with an introduction to the basic properties of quantum states of light and entangled systems. Later, we expand on the scheme proposed for the generation of multipartite entangled system. We go over the experimental implementation of this scheme and experimentally verify the existence of multipartite quantum correlated state
Ground-nesting birds in a changing climate: case studies of proximate behavioral mechanisms used by skimmers and terns to address seasonal variation in resources
Get PDFUnderstanding how species will adapt to anthropogenic climate change is one of the greatest challenges for ecologists and evolutionary biologists. For organisms with low dispersal abilities, rapid adaptation will often be critical for survival. Some species, primarily microorganisms and invertebrates with short generation times, might be able to adapt to changing environmental conditions or evolve in response to climate change. For species with longer generation times, the unusual rate and extent of anthropogenic alterations of the environment may exceed the capacity of mechanisms that populations have evolved to deal with environmental change. It has been posited that behavioral plasticity can reduce exposure to selective pressures and shield population from climate extremes. For this dissertation, I focus upon behavioral mechanisms that are used by individuals and populations to mitigate selective influences upon reproduction. Specifically, the chapters in this dissertation focus on dietary plasticity, alteration in parental reproductive strategies, and seasonal alteration in migration strategies. Combined, the three chapters provide support that phenotypic plasticity in behavior can be an important mechanism used address varying selective pressures in changing environments for longer lived species such as the Black Skimmer and Gull-billed Tern. For dietary generalists, having a degree of opportunism is valuable in changing climates where food resources are vulnerable to changing climactic conditions. Having the ability to alter parental investment, in the form of nest attendance and offspring provisioning can influence offspring survival by accelerating the advancement of offspring to the next developmental stage. And by adjusting migration strategies, individuals can control investment in time and energy allocation which thereby influences both reproduction and individual survival
Ravenscroft (34BV198) Bison Skull Piles: Explorations of Purpose and Meaning
Get PDFRavenscroft is a late Paleoindian arroyo bison kill located along a tributary of the Canadian River named Bull Creek in the Oklahoma Panhandle. Multiple field seasons eventually identified two stacks of bison skulls at the mouth of the arroyo. All but one of the skulls were missing mandibles. None of the skulls exhibited bashing, suggesting they were not set aside for brain removal. Two arroyos were identified, labeled RAV I and RAV II. Further complicating interpretations of purpose were the returned radiocarbon dates. Included in the piles were skulls representing at least three of the five kill events. These skulls span over 300 years of history, implying a much more complex purpose than subsistence or stockpiling. Through further analysis and comparison with other occurrences of stacked skulls worldwide, this thesis explores the potentially ritualistic aspects of this site and attempts to explain the purpose of the stacked skulls
Observation of opposite sign WW with an associated photon production at a center of mass energy of 13 TeV with the ATLAS detector at the LHC
Get PDFThe analysis presented in this thesis expects to provide the first observation of the opposite sign WW with an associated photon process and to measure its fiducial cross section. The analysis uses proton-proton collision data collected between 2015 and 2018 using the ATLAS detector at a center of mass energy of 13 TeV corresponding to an integrated luminosity of 139 inverse fb. Only events where one W boson decays to an electron and the other W boson decays to a muon are considered. Significant deviations from the measured opposite sign WW with an associated photon production cross section and the Standard Model (SM) prediction can provide evidence for beyond the Standard Model (BSM) physics. In addition, any deviation from the SM prediction can be parameterized in the framework of an effective field theory (EFT) and limits can be placed on these EFT parameters. The results of the EFT measurement are beyond the scope of this thesis and will be presented in another thesis. The majority of the background events arise from processes with prompt photons including tt with an associated photon and Z boson production with an associated photon. The analysis also considers backgrounds from non-prompt photons from electrons or hadrons. To improve the measurement sensitivity, a BDT (boosted decision tree) is trained using several well modeled input variables. The BDT combines the information from the input variables into a single variable: the BDT score. The opposite sign WW with an associated photon fiducial cross section and statistical significance are calculated by performing a binned maximum likelihood fit using the BDT output distribution. The expected statistical significance of the measurement is 7.2 σ and the expected fiducial cross section is 10.5 ± 14% (cross section) ± 15% fb (measurement). Where the cross section uncertainty is associated with the determination of the fiducial volume and the measurement uncertainty is associated with the determination of the signal strength using the binned maximum likelihood fit
Clustering Techniques in Multi-Objective Optimization: Applications in Climate-Driven Refugee Relocation
Get PDFAs climate change becomes increasingly concerning around the world, and with large uncertainty falling on the aspects of displaced people, a need for planning is prevalent. This complex problem—of which there is little to no preparation for—will require a comprehensive look into the different layers of the pathways to resettlement. The current process for refugee resettlement is not suitable for the prospective increase in the number of displaced people due climate related incidents, nor does it consider climate resettlement apart of the growing refugee population at the time. As this problem has proven to be laborious and extensive in the number of attributes to be considered, the goal of this study is to expand on a developing multi-objective optimization (MOO) problem by displaying how applying clustering methods can be beneficial to a resettlement plan for decision-makers. By applying k-medoids clustering (PAM) to host locations, the proposed addition aims neutralize some of the error in the arduous resettlement plan, provides the ability to adjust the granularity of focus, and takes a more practical look into an unknown, multi-faceted future