37200 research outputs found
Sort by
Estimating Electric Power Consumption of Grid-Enabled Residential Heat Pump Water Heaters
No full textWe present two methods for estimating compressor electric power consumption of residential heat pump water heaters. Power is calculated using data from voltage and current instrumentation, which add costs and potential failure points to the unit. The two methods presented herein use thermal instrumentation or derived data that are typically included within modern residential heat pump water heaters. One method uses data from lower and upper tank temperature sensors. The other method uses an attribute that is commonly available within grid-enabled flexible load heat pump water heaters. For both methods, fit equations were derived, for which coefficients are tuned to achieve a reasonable fit between estimated and measured electric power consumption. Within this paper, we describe the fit equations and the methods for tuning the equation coefficients. We also present metrics of fit between measured and estimated power consumption, sensitivity analyses of the fit equation coefficients, and validation analyses of a tuned fit equation using multiple data sets
Regional and District Trends in Oregon’s Post-Pandemic School Enrollment and Achievement
No full textOregon has been highlighted as a state with large student enrollment changes after the pandemic, as well as persistent learning loss. Unlike many other states in the nation, this learning loss has persisted. This paper goes beyond the statewide trends to examine regional and district level patterns in both enrollment changes and learning outcomes. One major finding is that while districts in all regions experienced enrollment changes, Large Urban and Suburban districts had notable enrollment declines. These declines were driven by a decrease in White students. Meanwhile, Suburban districts had increases in Asian, Black, and Multiracial students. Another finding is that while student proficiency rates in ELA and Math declined across the states, some large Urban districts, such as Portland Public Schools, were able to mitigate pandemic challenges while other Suburban districts struggled to do so. Finally, the growth of enrollment in Virtual Schools is also described
Leaden Circles, Eternal Springs, and Rusty Pumps: Time, Nature, and Industry in Mrs. Dalloway
No full textThis article explores often-overlooked ecocritical aspects in Virginia Woolf’s Mrs. Dalloway, analyzing Woolf’s literary intersection of time, nature, and industry as a precursor to contemporary Anthropocene discourse. Acknowledging prevailing interpretations of Mrs. Dalloway through social lenses of trauma, class, and gender, Evans reveals how Woolf’s exploration of human-environment relationships is not only present but integral to interpreting the text fully. Drawing from textual close readings, scholarship on Woolf, and environmental humanities frameworks, Evans demonstrates how Woolf utilizes the Big Ben and a beggar woman to symbolize human-nature relationships. Evans’ ecocritical reading of Mrs. Dalloway repositions the 1925 novel within contemporary discussions about humans’ evolving relationship with the natural world. This reading offers a model for integrating perspectives of the Anthropocene into literary analysis to deepen social discourse about gender, class, trauma, and urbanity
Retention Intervention Program Success: An Inquiry Into Learning Organization Structural and Cultural Elements in California Community Colleges
No full textCommunity colleges serve a diverse, underrepresented, and economically disadvantaged student population, yet most students fail to complete their academic goals, with students from marginalized groups facing even more significant disparities. Some colleges have implemented Early Alert and Intervention (EA&I) programs to improve retention and completion rates. However, colleges may face organizational challenges in implementing and sustaining these retention programs. This qualitative study examined structural and cultural elements in community colleges that have successfully implemented EA&I programs, focusing on student services and student affairs practices that support a learning-centered environment. Findings suggest that effective EA&I programs are grounded in inclusive, collaborative, student-focused cultures, shared goals and vision, cross-functional communication, cross-hierarchical leadership, participatory governance, ongoing professional development, and continuous program improvement. Based on these insights, the study offers actionable recommendations for colleges aiming to implement or enhance their EA&I efforts
Is Ride-Hailing a Potential Solution for Older Adults After Driving Cessation? The Role of Objective and Perceived Accessibility
No full textDue to age-related physical and cognitive changes, older drivers have a greater risk of crashes and are restricted by age-dependent regulation. Nonetheless, many older adults in the United States maintain a car-dependent lifestyle and still prefer driving. When driving cessation or reduction becomes necessary, a primary concern is finding suitable alternative transportation modes. However, the availability of alternative transportation modes does not guarantee their actual use of these options.
As a relatively new transportation mode, ride-hailing services, such as Uber and Lyft, offer on-demand, door-to-door transportation and may be a feasible transportation solution for older adults who stop driving. While accessibility is often defined as access to opportunities, this study focuses on access to transportation itself--whether individuals can access and use alternative transportation services. This dimension is particularly relevant for older adults who may face physical, psychological, or technological barriers to accessing ride-hailing services.
This dissertation aims to investigate whether ride-hailing can be a potential solution for older adults who stop driving by examining both objective and perceived accessibility. Access to transportation is influenced not only by transportation service availability but also by individuals\u27 perception of ride-hailing. Therefore, this study examines the distinction between the actual availability of ride-hailing services and whether older adults perceive and adopt these services as their alternatives to driving.
The dissertation presents the main findings in two papers, supplemented with some additional analysis of ride-hailing trip characteristics. The first paper uses regional travel survey data from the Chicago Metropolitan Area, the Twin Cities Metro, and the Puget Sound Region to identify factors influencing ride-hailing adoption. To better understand age-related differences in ride-hailing use, the study compares segmented models across three age groups: younger adults (ages 18-54), middle-aged adults (ages 55-64), and older adults (ages 65+). This segmentation allows for the examination of middle-aged adults as a distinct group to provide insight into the future older adult population. Although current differences may reflect cohort effects, this group is approaching older age. The second paper investigates how older adults perceive ride-hailing services and their willingness to use them. This paper is based on semi-structured interviews with 18 older adults in the Portland, Oregon metropolitan area, to identify perceived barriers, concerns, and unmet needs related to ride-hailing services. Finally, additional analysis examines trip characteristics of ride-hailing across age groups. Due to the limited number of ride-hailing trips among older adults in the survey data, this analysis combines data across all three metro regions to compare trip distances, duration, and purposes between age cohorts
Dynamics of Urban Heat and Green Infrastructure
No full textThis dissertation provides a comprehensive analysis of the interaction between urban heat and green infrastructure (GI) in terms of dynamic aspects, spatiotemporal variation across various spatial scales, temporal phases, and socioeconomic contexts. By integrating a national-scale longitudinal analysis, street-level structural assessments, and neighborhood-specific resilience frameworks, this study enhances our understanding of how cities can utilize existing ecological assets to mitigate increasing heat risks while addressing systemic inequities.
Urban areas face unprecedented thermal challenges due to climate change and the urban heat island effect, with marginalized communities disproportionately affected. Although cities are increasingly adopting GI expansion for heat mitigation, significant knowledge gaps remain regarding the spatiotemporal complexity of thermal dynamics and their socio-ecological implications. This research utilized a unique pedestrian-level air temperature dataset from the National Integrated Heat Health Information System (NIHHIS) Heat Watch Campaign to explore these dynamics through three interconnected studies.
The first study investigated decadal changes (2013/14-2022/23) in urban greenery across 33 U.S. cities, employing satellite-derived vegetation indices and high-resolution urban air temperature maps. The findings revealed accelerated greenery loss in the hottest neighborhoods, with 69.7% of cities showing inverse relationships between heat burden and conservation efforts. A 150m grid-cell analysis highlights systemic preservation failures, indicating that current urban forestry policies inadequately protect vegetation in thermal hotspots.
The second study, conducted across four mid-latitude cities (Portland, Washington D. C., Philadelphia, and Boston), integrates vehicle-collected air temperature data with municipal tree inventories to assess cooling performance. These results indicate that tree diameter at breast height (DBH) is a significant predictor of microclimate cooling. Neighborhoods with the coolest microclimates have trees with an average DBH 2.87 inches (7.29 cm) larger than those in warmer neighborhoods, which tend to be less affluent areas, suggesting a temporal disparity of over a decade in tree maturity.
The resilience framework for the Portland Metro area distinguishes between resistance (afternoon-evening cooling) and recovery phases (evening-morning cooling). Through clustering analysis, seven neighborhood typologies were identified, revealing phase-dependent effects of urban characteristics. Areas with 30% canopy coverage optimized both resilience phases, whereas those with coverage exceeding 40% hindered overnight cooling. Socioeconomic disparities were apparent, with lower-income areas experiencing elevated temperatures, and low recovery cooling was correlated with racial demographics. The resilience framework offers planners a tool to evaluate neighborhood thermal performance, such as the cumulative heat exposure introduced in the study, and to identify phase-specific intervention needs.
By bridging the spatial and temporal scales, this dissertation offers evidence-based recommendations to assist cities in addressing heat inequities while enhancing ecological resilience. As urban temperatures rise, so must our commitment to stewarding existing ecological assets in the communities that need them most. The path to urban heat resilience lies not in planting our way out of crisis, but in protecting what already exists
An Exploration of Holistic Admissions Protocol in Graduate School: Implications for Access and Equity
No full textHistorically, graduate admissions policies at higher education institutions have heavily relied on standardized testing, which limits access to graduate and professional degrees for underrepresented demographic and gender groups. Recently, movements toward holistic graduate admissions processes and strengths-based evaluations of applicants have shown promise in equitably recruiting and admitting candidates. However, the field currently lacks common best practices and strategies for enhancing equity in the evaluation of applicant credentials. Furthermore, recent federal challenges to campus diversity and inclusion efforts have complicated these initiatives. To address these issues, this qualitative comparative case study examined five university graduate schools that are implementing holistic admission processes. Alongside data from interviews with institutional administrators, the study collected and analyzed policies, tools, training, and assessment efforts aimed at promoting equitable consideration of applicants. The findings revealed specific organizational frameworks that effectively support the operationalization and sustainability of holistic admission efforts: lateral coordination of efforts; coalitions that recognize power and privilege; empowerment and motivation in training; and the development of evaluation rubrics that reflect an institution\u27s mission and vision
Isolation Enhancement Based on TM010 and TE30 Mode Characteristics in a Patch Antennas Using Genetic Algorithm Optimization for Ku-Band Applications
No full textThis paper proposes a novel technique to enhance isolation in rectangular patch antennas by leveraging the mode characteristics of TM010 and TE30 to achieve better than −40 dB between the transmitter and receiver with dual‐polarization features. The primary innovation of this work lies in achieving significant isolation enhancement solely by combining two resonant modes with orthogonal polarizations, without incorporating any additional design elements such as parasitic components or decoupling structures. To validate the isolation enhancement based on these mode characteristics, a pair of rectangular transmitter and receiver patch antennas was designed to operate in the frequency range from 14 to 14.25 GHz. The transmitter antenna was designed using the TM010 mode with horizontal polarization, while the receiver antenna used the TE30 mode with vertical polarization. The design utilized a Rogers 3003 series dielectric substrate with a dielectric constant of 3.3 and a loss tangent of 0.003. A genetic algorithm with tournament selection and a multiobjective function was applied to optimize key performance metrics, such as impedance matching, bandwidth, and gain. Following successful optimization, the simulated results were validated against measurements, showing excellent agreement and confirming the accuracy of the proposed antenna design
Convergence Research for Sustainable Regional Systems
No full textSummary:
Convergence research addresses societal and environmental challenges by co-creating knowledge across disciplinary boundaries, often in deep collaboration with extra-academic parties to ensure that the research process is solution-focused, actionable, and just. As part of National Science Foundation (NSF)-funded research projects on sustainable regional systems, we present multiple perspectives on conducting convergence research within the coupled social-ecological-technological systems framework. These projects explicitly engage extra-academic parties to co-design and co-produce knowledge throughout all stages of this participatory research. We introduce the 3 C’s model as a framework that links a research team’s Communication, Collaboration, and Creation decisions to the likely degree of convergence and societal change achieved. This model assesses the degree of integration among different social sciences, biophysical sciences, engineering, and other scientific disciplines, as well as extra-academic partners ranging from governmental agencies and industries to non-profit organizations and tribal communities. Integration in this context is assessed by its ability to situate local problems within broader systemic lenses, resolve conflicts among the priorities of partners, and conduct cutting-edge research that addresses real-world needs with actionable sustainability solutions. By synthesizing inclusive and just practices of conducting convergent research across a selection of research teams, we provide recommendations for academic researchers and administrators to encourage and advance convergence research in solving challenging sustainability issues
Fueling Adaptation: Collaborative Wildfire Governance in the Colorado Front Range Landscape
No full textCollaborative governance plays a critical role in wildfire risk mitigation efforts. This study examines collaborative wildfire governance networks within the Colorado Front Range, a landscape that was designated under the USDA Forest Service\u27s Wildfire Crisis Strategy (WCS). Collaborative governance networks in the Colorado Front Range leverage partnerships across multiple organizational actors including federal, state, and local agencies, non-profits, fire districts, and research institutions. Through survey data collected from 281 respondents revealing a collaborative network of 401 organizations, the study aimed to identify the structure, capacity, and gaps in governance networks addressing wildfire risk in the Colorado Front Range. Survey results reveal a collaborative network that is led by non-profits and governmental agencies forming a dense core of highly connected organizations with peripheral actors engaged in more targeted partnerships. However, our findings reveal that notable gaps remain in the engagement of Indigenous communities, private-sector entities, and smaller local governments, indicating the need for targeted capacity-building and outreach efforts. Building such collaborative capacity is a gradual process that depends on sustained engagement and long-term investment. Partnerships involved a mix of formal agreements, funding flows, and informal collaboration. According to respondents who reported that their organization was influenced by the WCS, federal investment helped improve collaborative conditions and produced better collaborative outcomes, including greater trust, alignment, and improved landscape-level results