A significant change that employees in the United States have experienced because of the COVID-19 pandemic is the rise of remote work. There are many benefits of remote work, including increased performance and productivity. However, many remote workers struggle to separate work and life, leading to increased work-life conflict. Parents working remotely during the pandemic were the most likely to report challenges keeping work and life separate. The goal of this study was to better understand how parents’ work-life boundaries have changed during the pandemic. Based on interviews with 16 mothers and 16 fathers, this study examined how parents’ preferences for keeping work and life separate have adjusted and what factors affect their work and life. This research also looked at how mothers and fathers differ in their strategies to navigate between work and life when working remotely. This research uncovered six themes on how parents managed their work-life boundaries: two mindset shifts and four work-life separation strategies. Parents adapted their mindsets by redefining their priorities and setting realistic work and family expectations. The four boundary management strategies were turning off technology, sticking to a schedule, designating a home office space, and using a door-closed policy.
Peak load forecasting is crucial for reliable and effective grid operation. The day-to-day operation of the power grid requires load scheduling and dispatches of different energy resources including Energy Storage System and Demand Side Management programs. An effective implementation of these peak-shaving strategies relies heavily on when the peak demand occurs. Hence, forecasting the timing of peak load is as important as forecasting its magnitude.
A review of relevant literature indicates that there is no inclusive study on the topic of peak timing forecasting. This research aims to bridge the gap between industry requirements and academic research by addressing some key questions. First, the study defines the different forms of peak timing problems that arise in grid operation. Next, we investigate the problem of how we measure the peak timing forecast errors. The research critically reviews error measures used in the literature for peak timing forecasting. Based on the findings five new application-specific error measures are proposed. The research then focuses on one of the manifestations of the peak timing problem, that is, forecasting daily peak hours.
We analyzed the accuracy of peak hour forecasts from a state-of-the-art hourly load forecasting model and set it as the benchmark. The model selection process using different peak timing errors and load shape errors is investigated. Furthermore, two different frameworks for peak hour forecasting have been developed. The effectiveness of the proposed frameworks is empirically demonstrated in two case studies. The first case study is from a medium-sized Utility in the U.S. and the second one is from ISO New England. The proposed models demonstrate improved forecast results on the benchmark model by 12-16% in the test years of the two case studies. Additionally, when the models are only evaluated on the critical days with very high demands, they outperform the benchmark by 25-53%. Findings from this study emphasize the importance of developing explicit models for peak hour forecasting by analyzing the key determinants that vary with geographical location and regional factors.
This dissertation analyzes performance distribution, the financial impact of star performers, and how the researcher's discipline moderates the relationship between individual performance and the value of external funding at a private R1 institution. While publications have traditionally served as a metric for faculty success at research institutions, there needs to be more knowledge regarding the role of star performers in securing external funding. Data drawn from the institution's internal application system encompassed a sample size of 7,213 proposals submitted by faculty members over five years. Utilizing the Dpit package from the Comprehensive R Archive Network (CRAN), results indicate that a power law distribution offers a better fit than a normal distribution for modeling star performance, with a significant portion of generated value concentrated among a select group of star performers. Furthermore, the research demonstrates that an organization's strategic core competence moderates the individual performance of researchers and the overall value derived from research initiatives.
There is a growing mental health concern among Black Ratchet queer womxn in educational and criminal justice realms and the Covid-19 pandemic has left the educational climate in a state of high stress and anxiety. Consequently, Black Womxn in education are quitting from burnout. According to research, teacher burnout has been a concern for more
than 30 years, but currently there is a crisis. According to research “This is a five-alarm crisis. We are facing an exodus as more than half of our nation’s teachers and other school staff are now indicating they will be leaving education sooner than planned.: (Jotkoff, 2022).
Covid-19 has caused an increase in depression, anxiety, suicide ideation, and other health concerns in this population. External hindrances including racism, sexism, homophobia, and other ideologies rooted in America; negatively influence their mental well-being. Black queer womxn and girls are restricted from obtaining proper access to mental health services that take into consideration how identities are critical factors in mental well-being. This analysis will provide a rationale for utilizing culturally relevant mindfulness practices for Black queer womxn in educational sectors.
This dissertation embarks on a comprehensive exploration of the intricate dynamics surrounding access to and appreciation of natural environments within urban parks among the Latine population in Mecklenburg County. The central goal is to explore how Latine communities engage with urban natural spaces, affecting their perceived well-being. Through rigorous research, it investigates how human-environmental interactions in urban green spaces influence perceptions of well-being and their potential to mitigate disparities in access to such spaces and health outcomes. This study contributes significantly to the understanding of the interplay between urban green spaces, cultural perspectives, and well-being within the Latine community, addressing broader issues of environmental equity and health disparities. It enhances the geography literature by examining human-environmental interactions in urban parks within ascending Latine communities in the southern region. By integrating Michel Foucault's power and biopolitics theories and Landscape Theory. The research sheds light on the mechanisms of social control, access, and the cultural dimensions of landscapes. This research has implications for policy development, urban planning, and environmental management, aiming to promote equitable access to urban green spaces such as parks and improve health outcomes for marginalized communities.
Seasonal cold weather and frost action has a major effect on the design, construction, performance, and maintenance of roadways. Frost heaving and thaw weakening are especially problematic, subjecting all elements of a pavement system to significant changes in moisture content, stress, and strain. Nationally, this leads to recurrent annual maintenance costs estimated at over 2 billion dollars, as well as additional economic impacts because of related vehicle damage, road closures, and weight restrictions. Studies identify three basic requirements for frost action; freezing temperatures, availability of water, and frost-susceptible soils. While advances have been made in designing for freezing temperatures and providing for groundwater separation, very little progress has been made in terms of in situ soil improvement. A cost and labor-intensive approach is to replace unsuitable soils. As an alternative, Engineered Water Repellency (EWR), a process in which soils are made hydrophobic is presented as a suitable barrier limiting the transport of water through these soils, resulting in frost heave mitigation. This is achieved by combining soils with cost-effective and environmentally compatible polymers and other complex organic molecules. This process explored through a multi-year project funded by the U.S. National Science foundation, involved laboratory, field, and numerical studies.
The increasing threats posed by climate change and urbanization have elevated the importance of addressing Urban Heat Island (UHI) phenomenon, a critical concern impacting cities across the United States. This dissertation comprises three articles that collectively investigate the effectiveness of trees and greenspaces in managing UHI, creating a Heat Health Score (HHS) to identify areas experiencing UHI effects and investigate the perceived effectiveness of policies and programs aimed at reducing UHI in cities, while providing recommendations for Charlotte, NC in particular. Article 1 shows that urban greenspaces consisting of trees can help reduce the UHI effect by creating shade and cooling spaces, potentially reducing energy costs, improving human living conditions, providing food and habitat to wildlife, and improving aesthetics and land values. In Article 2, measures to mitigate the effect of UHI are evaluated from select cities and a ratio of daily average high temperature between locations and the corresponding difference in land cover of tree and shrub areas, create the Heat Health Score (HHS) (a unique metric) which allows municipalities and community groups to gauge the heat health between locations. These results show that most urban locations remain hotter and with lower vegetative cover than their suburban or rural counterparts, however, changes in tree and shrub cover can impact these results in a positive way. Results from Article 3 elucidate the perceived successes and challenges of current policies through a qualitative survey. These responses offer practical recommendations for policymakers across the US but for Charlotte, NC in particular.
These results draw from the real-world experiences and lessons uncovered in the three articles, in aggregate, these provide a valuable resource for city leaders and policymakers striving to create a more sustainable and climate-resilient city. It stresses the importance of urban greenspaces and urban trees in particular, provides community leadership with an easily accessible, not previously defined tool to discern urban heat health through the use of free, open-source data to score heat health, and provides insight into the perceived effectiveness of policies and programs used to mitigate UHI in cities in the United States.
Renewable energy resources advancement and offerings are steadily increasing, a major factor leading to its global fast adoption. The connection of these resources to the electric grid, however, needs to be studied to ensure efficiency both from an operational and regulatory standpoint. The IEEE 1547 has been used to establish standards for grid interconnection of some renewable energy resources (RERs). In this dissertation, the operations of RERs connected to the grid with respect to their control, management, and optimization are studied. It is of note that RERs are intermittent in nature and this can have effects on the power quality metrics or utility objectives on either network separately or collectively. For instance, the stability of the grid can be affected due to the low inertia of these resources, which can impact the voltage or the grid frequency. A novel adaptive controller was developed to damp the oscillations caused by these RERs, the controller was initially tested with RERs in one network architecture, and it offers advantages such as dynamically responsive support to the grid to control the frequency, a frequency spectrum was used to determine the amount of support required in an adaptive manner. The architecture was then expanded to a network model that has both transmission and distribution networks integrated together with the interconnection of multiple RERs connected to the grid, the capabilities of the proposed architecture were evaluated with different test cases with different grid events. The architecture had the capability to control multiple generators as well as damp the oscillations observed during the test cases and simulations performed, by adaptively updating the gain of the power system stabilizers (PSS).
On the management side, A new technique was developed with grid-connected RERs that provide real-time visibility of two integrated networks during operation. Presently, the operations don't offer such capabilities as the transmission system operator (TSO) is often times blind to the distribution system operator (DSO). Our technique makes it possible for the transmission network to adjust itself in real-time in case of sudden changes in the distribution network with RERs connected, A stochastic linear optimization technique; Linear decision rule (LDR) that establishes the relationship between the generators in the transmission network and the RERs in the distribution network was implemented, the technique addresses one of the major issues with integrated T&D networks which is boundary mismatch caused by the reverse power flow from the distribution network, in addition to offering the operational advantages required by most utilities like minimization of voltage deviation, and minimization of cost of operation, as it eliminates the need for curtailing RERs which is the current implementation used by most utilities, the technique theorem proof was also discussed. Furthermore, Grid Connected RERs are multiperiod in nature, it is therefore imperative to study their behavior at each time interval, the optimization framework was extended to such studies to handle the reverse power flow operation due to the irradiance daily curve, and the optimal power flow formulation was transformed to multiperiod optimal power flow MPOPF. The effectiveness of the proposed architecture was tested with an irradiance curve, and a typical residential load curve, it demonstrated the capability to reduce the boundary mismatch while ensuring the grid objectives for each network were achieved. Finally, the impact of electric vehicle charging was studied and a management approach was developed, Electric vehicles (EVs) adoption is also increasing impacts of the distribution network on the transmission network with respect to grid penetration, we developed a two-stage stochastic linear optimization in the integrated T&D to handle the uncertainty with electric vehicle charging and compared with effective EV charging management technique that was developed.
As the entry point into higher education for over half of the bachelor’s degree earners, (Trapani & Hale, 2019), community colleges are positioned to have a positive impact of bringing a more diverse student group into science, technology, engineering, and mathematics (STEM) majors. However, the vertical transfer function from community colleges into a four-year university is often not clear resulting in a gap between those with transfer aspirations and bachelor degree attainment. There are unique barriers that women of color transfer students encounter that can threaten persistence in STEM. This study contributed to the few studies (Allen et al., 2022, Jackson, 2013, & Reyes, 2011) that have focused on the experiences of women of color in STEM and transfer. The purpose of this qualitative phenomenological transfer student study was to understand how pre- and post-transfer women of color in STEM majors experience the transition into university from community college in North Carolina. This longitudinal study used interview data from 14 women who participated in a larger transfer study. Six of the women provided three interviews. Guided by the reconceptualized model of multiple dimensions of identity (Abes et al., 2007), the role of social identities and the impact on educational decisions was explored. Five major themes were identified: (1) the internalization of community college stigma, (2) blindsided: post-transfer rigor, (3) the loss of personal connection post-transfer, (4) feeling behind and other perceived roadblocks for STEM transfer students, and (5) can’t do it alone: leaning on support networks for success. The findings from this study led to recommendations to the current articulation agreement structure in North Carolina, and recommendations for post-transfer institutions to better support women of color in STEM.
The rapid proliferation and widespread adoption of microgrids (MG) necessitate the
development of new methodologies to holistically model all the active components
within MGs. It’s crucial to focus on specific islanding requirements, especially when
the primary grid power is unavailable. In order to ensure a high level of reliability
in an interconnected MG network, this dissertation presents an optimal scheduling
model designed to minimize the day-ahead costs of the MGs while taking into account
the existing operational constraints.
This problem is thoughtfully decomposed using Bender’s Decomposition method
into two key operating conditions: grid-connected and resilient operations. The ultimate
goal is to ensure that each MG within the network maintains sufficient online
capacity in the event of an emergency islanding situation, such as during extreme
weather events. These events often come with uncertainties regarding their timing
and duration, necessitating the consideration of multiple potential islanding scenarios
for each event.
The primary objective of this thesis is to establish optimal scheduling that guarantees
the feasibility of islanding for all conceivable scenarios of such events, with
load shedding as a last resort. The optimization model has been put into practice
across different layouts of the modified IEEE 123-bus test system, encompassing various
events over a 24-hour period. In addition to proposing a day-ahead scheduling
approach oriented towards resiliency for multiple MGs, a comprehensive cost analysis
and comparisons among all the test cases are also offered. The results convincingly
demonstrate the utility of the proposed day-ahead scheduling algorithm, particularly
for MG owners looking to foster collaborations with neighboring MGs. Lastly, after
iv
comparing with the traditional Single Stage MILP approach, the proposed method
has proven to be computationally faster for practical usage. It has been shown that
decomposing the problem using the proposed model makes it possible to combat real
life events with thousand scenarios, where the single stage approach may fail.