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Leveraging P4 Programmable-Hardware Switches for In-Network PMU Packet Recovery
Get PDFPhasor Measurement Unit (PMU) systems are essential for real-time power grid monitor- ing but often face data loss due to network delays, equipment malfunctions, or transmis- sion errors. Traditional centralized recovery solutions introduce significant latency and scalability challenges. This thesis presents a P4-based in-network recovery mechanism that embeds detection and recovery directly into the data plane of P4-enabled programmable switches, significantly reducing recovery time and infrastructure complexity. Using the Aurora 610 switch, the system detects missing packets via sequence number analysis and recovers magnitudes with an efficient register-based algorithm.
Evaluation demonstrates high accuracy and low latency, achieving a mean absolute percentage error (MAPE) of 0.39% and an average processing latency of 336.99 nanosec- onds with a 2.52-nanosecond standard deviation at a 5% packet loss rate. These results highlight the potential of programmable networks for scalable, efficient, and resilient PMU data recovery, advancing grid monitoring and anomaly detection in real-time applications
Development of a Manifold Microchannel Heat Sink for the Electrification of Aircraft
Get PDFThe miniaturization of microprocessors and power electronics is leading to critical thermal management challenges. For instance, the heat flux generated in modern computer chips is at the order of 100W/cm², which is well beyond the limit of air cooling. This high heat generation can cause a variety of thermal or mechanical failures in electronic devices. As such, there is a pressing need to devise effective cooling strategies for these microelectronic devices. Liquid cooling with microchannel heat sinks is a promising technology for high power loads. Nevertheless, traditional heat sinks with straight microchannels suffer from two critical challenges: high pressure drop and low-temperature uniformity. To address these challenges, this paper presents a 3D manifold microchannel heat sink developed using metal additive manufacturing. The flow structure and the microchannels help reduce the flow length in the across the device, reducing pressure drop, and minimizing temperature imbalances throughout the heat sink. To enable the fabrication of 3D flow structures, this novel heat sink is printed using direct metal laser sintering with 6005 aluminum alloy. The heat transfer coefficient and pressure drop of the 3D manifold microchannel heat sink were characterized by flow tests using an in-house liquid test loop. The final manifold design had a thermal resistance as low as 0.51 K/W and a pressure drop of 1.5 kPa. The manifold structure helped reduce the pressure drop for flowrates less than or equal to 0.4 L/min. This heat sink will lead to improved performance and reduced costs of thermal management systems in various industries and applications, including wafer-scale engines for supercomputing, amplifiers in radar systems, and high-voltage, high-frequency converters, inverters, and transformers in power grids and electrical propulsion systems
Editor\u27s Comments
Get PDFWelcome to Volume 8 of the Journal of Research on the College President. In this volume, you will find three exceptional studies that help provide an even stronger understanding of what has been described as one of the hardest jobs in not only in higher education, but in the country. These three articles were accepted through our peer review process, and this year we had 11 submissions, resulting in a 27% acceptance rate
Inquiry: The Unversity of Arkansas Undergraduate Research Journal - Volume 23 Issue 1 - Spring 2024
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Essays on Corporate Fraud and Racial Animus
No full textThis dissertation consists of two essays focusing on the effect of corporate fraud on mutual funds’ portfolio decisions and the impact of racial and ethnic animus on fund performance. The first essay examines how sophisticated investors respond to a higher corporate fraud intensity in a state. We find that mutual funds hold less equity in non-fraudulent local firms when the state-level fraud intensity is higher, and the result is concentrated in short-horizon funds but not for long-horizon funds. To establish causality, we employ Regulation SHO in 2004 as a plausibly exogenous event to corporate fraud intensity and find affirmative results. Increased holding and information cost for mutual funds when a state’s fraud intensity becomes higher appear to be the underlying mechanisms that help explain the finding. Overall, our study provides new evidence on how information risk induced by corporate frauds affects mutual funds’ investment behavior and highlights the asymmetry in costs that short- and long-horizon funds face. The second essay explores the effect of sociopolitical racial/ethnic animus on work performance. During the unexpected 2020-2021 “AAPI Hate,” mutual funds with female managers perceived as of East Asian descent (the primary targets) experienced performance deterioration relative to other female managers. The impact intensified in states with higher anti-Asian crime rates or sentiment, among more actively managed portfolios, and when these managers play leadership roles. We address alternative hypotheses, including investor redemption, workplace animus, childcare challenges, and concerns for families overseas during the pandemic. Performance deterioration manifests itself mainly in stock picking. Our study highlights the negative productivity impact of racial-ethnic animosity even when it arises outside the workplace and the labor market
Bilateral Asymmetry in the First Metacarpal: The Influence of Handedness in Humans and Non-Human Primates
Get PDFMuscle attachment sites (entheses) are often used to infer soft tissue anatomy and reconstruct behaviors within skeletal populations, but there remains a significant debate about whether and to what degree muscle use is accurately reflected in bony morphology. One of the most difficult problems in establishing the relationship between variation in muscle use and entheseal development is the inability to exclude a variety of external factors thought to influence enthesis development, including age, sex, body mass, and activity patterns. One way around this is to take advantage of the fact that humans are handed (preferentially using one hand over another, regardless of task), therefore showing asymmetrical patterns of muscle recruitment in the hands. If a direct relationship between bony morphology and muscle recruitment does exist, one would expect to find strong asymmetry in entheseal development within human hands. Conversely, non-human primates do not exhibit handedness and should not show asymmetrical manual entheseal development. The m. opponens pollicis is heavily used in many key grips employed during precision manipulation and is active during flexion, abduction, and adduction during thumb opposition. As such, the muscle insertion on the radial aspect of the first metacarpal is an ideal site for testing if enthesis development is reflective of repetitive muscle recruitment. This study examines if lifetime activity patterns influence bony morphology by comparing opponens pollicis muscle enthesis asymmetry between handed (Homo sapiens) and non-handed (Hylobates lar, Gorilla spp., Macaca fascicularis) primates to identify if differences exist between dominant and non-dominant hands. Additionally, since thumb flexion and opposition span all three joints, the functional signal from precision pinch and grasps should not be confined to a single bony region. Enthesis asymmetry is therefore hypothesized to serve as a predictor for asymmetry in the proximal and distal ends due to their role in flexion and stabilization during key grips. This study measured enthesis size between the right and left first metacarpals in a sample (n=197 pairs) of adult modern humans and catarrhine primates using both measurements obtained from calipers and from distance-based heat maps generated from 3-D renderings. Results demonstrated right-directional asymmetry in the opponens pollicis enthesis in modern humans and symmetry for non-human primates for enthesis size. However, it demonstrated that increased muscle recruitment alone is not sufficient to induce significant differences between sides; rather, this study established there is a threshold for enthesis size that most individuals do not exceed, and that, to infer muscle use based on enthesis size, the individual must exceed this threshold. Further, this study found that asymmetry in the opponens pollicis enthesis can predict a moderate amount of asymmetry within the proximal and distal ends of the metacarpal, but also found that ligamentous recruitment contributes to asymmetry within those areas. Overall, this study found support for inferring muscle use based on enthesis size but cautions against making large generalizations based on size alone, as further research is needed to better understand the roles that both muscle recruitment frequency and intensity play in enthesis development
Hospitality Highway Career Fair: An Exploratory Study
Get PDFThe goal of this creative project is to conduct research on career fairs and hospitality events to successfully host the first ever Hospitality Career Fair at the University of Arkansas. The lack of career advancement opportunities on the campus for hospitality management students continued to increase despite the rapidly growing industry across the community, so the creation of the career fair would allow improvement for the students and the companies. With a creative project, it allows more creativity and research to develop the overall plan for the event.
The project studies hospitality career events hosted at other universities to gain specific knowledge on what aspects were vital to the execution of the event and how it impacts the students, university, and community. The research showed major positive points to implementing a hospitality specific career fair on a campus, and proved that creating this event would be an accomplishment for the University of Arkansas.
In addition, the execution of the career fair can produce more research on what specifically works for that community and campus and can be used for the future of the Hospitality Career Fair
Money Talks: Implementing Open Banking in The United States
Get PDFAn open banking system exists when a third-party financial service provider has access to consumer financial information. What if the United States could be on the forefront of the next banking industry change? A well implemented system would mean a new, accessible way to make a transaction. This Comment will explore how the United States can implement an open banking system. First, this Comment defines open banking against the backdrop of the traditional transaction model. Next, this Comment describes the United Kingdom’s adoption of open banking, focusing on the benefits and detriments created by its adoption. Third, this Comment describes key, existing regulations in the United States that should lay a foundation for open banking. Finally, this Comment seeks to attack two critical questions that must be answered before open banking takes hold in the United States: (A) what the standard is, and (B) to whom that standard applies