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ReMoDeL-FPGA: Reconfigurable Memory-centric Array Processor Architecture for Deep-Learning Acceleration on FPGA
Get PDFDeep-Learning has become a dominant computing paradigm across a broad range of application domains. Different architectures of Deep-Networks like CNN, MLP, and RNN have emerged as the prominent machine-learning approaches for today’s application domains. These architectures are heavily data-dependent, requiring frequent access to memory. As a result, these applications suffer the most from the memory bottleneck of the von Neumann architectures. There is an imminent need for memory-centric architectures for deep-learning and big-data analytic applications that are memory intensive. Modern Field Programmable Gate Arrays (FPGAs) are ideal programmable substrates for creating customized Processor in/near Memory (PIM) accelerators. Modern FPGAs contain 100s of Mbits of dual-ported SRAM in the form of disaggregated, configurable Block RAMs (BRAMs). These BRAMs contain TB/s of available internal bandwidth. Unfortunately, developing FPGA-based accelerators for deep learning is not a simple task and demands the utilization of specialized tools provided by the FPGA vendors. It requires expertise in low-level hardware microarchitecture design. These are often not available to most researchers in the field of deep learning. Even with the ongoing improvements in High-Level Synthesis (HLS) tools, the requirement for hardware-specific design knowledge cannot be completely eliminated. This research developed a new reconfigurable memory-centric architecture and design approach that opens the advantages of FPGAs and Processor-in-Memory architecture to memory-intensive applications. Due to its high-performance and scalable memory-centric design, this architecture can deliver the highest speed and the lowest latency achievable from an FPGA overcoming the memory bottleneck
Examining the Impact of Parental Punishment and School Punishment on Delinquency and Criminal Justice Contact
Get PDFPrior research states the important role that both parents and schools play in setting children up for success. However, few researchers have studied how parents and schools work in tandem to achieve these outcomes. The current study aims to fill this gap by understanding the relationship between parental harshness and exclusionary discipline at age 9, specifically suspension, and how it affects delinquency and later criminal justice contact at age 15. Using longitudinal data from the Future of Families and Child Wellbeing Study (FFCWS), this study aimed to answer the following two research questions: 1) Does increased parental harshness and harsh school discipline increase delinquent behavior? 2) Does increased parental harshness and harsh school discipline increase the risk of criminal justice contact, specifically, police stops and arrests? The results show that youth who were suspended at age 9 were more likely to engage in delinquent behavior at age 15. However, youth who felt strongly connected to their school were less likely to engage in delinquent behavior as a result. Parental supervision was significant, showing that parents with high levels of monitoring their children can lead to a higher risk of being stopped by police. Additionally, parental harshness was significant for arrest, showing that experiencing high levels of parental harshness may increase the risk of youth being arrested. Despite these mixed findings, this study adds to the literature by combining both parental and school measures for a more holistic understanding of children’s delinquent behavior and risk of CJ contact
Batch and Placement Size Effects on the Setting Time of BCSA Cement Concrete
Get PDFBelitic calcium sulfoaluminate cement (BCSA) is an alternative to portland cement which offers numerous benefits due to its rapid-setting behavior and sustainability properties. BCSA cement concrete has many potential applications, particularly for structural and transportation infrastructure repair. Due to the rapid-setting properties of BCSA cement, a comprehensive understanding of the setting process is critical for efficient and effective use of this material. The primary objective of this research was to determine the effects of mixture size on the setting time and temperature behavior of BCSA cement concrete, and to investigate the relationship between initial set time and workability. Using a constant mix design, several BCSA cement concrete mixtures were created to test both batch and placement size effects. Temperature and ultrasonic pulse velocity (UPV) testing were performed to estimate the initial set time for all mixtures. A further set of mixes was performed to evaluate the relationship between initial set time and workability for BCSA cement concrete. Mortar penetration, temperature testing, and UPV were all monitored for each mix, while a workability relationship was estimated using the slump test. Overall, some changes in initial set were found for BCSA cement concrete as batch sizes were increased, but temperature and citric acid retarder dosage likely played a more significant role in the changes to initial set time. Likewise, minimal differences were seen in initial set time for mixes of varying placement size. Furthermore, the study found that the initial set time determined using mortar penetration gives a good approximation for the actual working time of BCSA cement concrete. An ultrasonic pulse velocity of 3500 m/s was also found to be a fairly accurate approximation for both penetrometer initial set, as well as working time for BCSA cement concrete mixtures. Overall, common estimates for initial set generally approximate the workability of BCSA cement concrete mixtures, while UPV has the potential to be used as a setting time test
Geochemical Analysis of Basement Rock as a Potential Metal Source in Mississippi Valley-Type Ores, Southern Midcontinent U.S.A.
Get PDFMississippi Valley-Type (MVT) ores are epigenetic, sedimentary hydrothermal base metal deposits that exist worldwide with type localities in the midcontinent United States. These Permian-aged sulfide ores represent an extraordinary concentration of economic metals, Pb and Zn. Ore deposits occur in vast districts that have a rich mining history. The Pb and Zn from these deposits account for 24% of worldwide reserves. The geologic processes responsible for MVT ore genesis are not fully understood, especially the sourcing of ore constituents. In the midcontinent, the Ouachita Orogeny expelled saline hydrothermal brines in response to high rates of subsidence. These fluids migrated through Arkoma Basin carrier beds and faults to deposit MVT ores up-dip within basin flank carbonate hosts. Base metals were leached into solution from surrounding wall rock, and metals traveled within the fluid to the ore deposition site. Which lithologies had a greater metal contribution is unconstrained. Lead (Pb) isotopes can be used to investigate potential relationships between geologic features. Southern midcontinent ores show highly radiogenic Pb signatures, so a lithologic metal source must have a similar isotopic nature. Precambrian basement rock has been a long-hypothesized metal source due to generally higher concentrations of radiogenic Th and U, evidence of hydrothermal alteration, and ore Pb source model ages yielding a 1.01 and 1.05 Ga Pb source. Fifty-three basement samples from the Central Plains Orogen (1.65-1.8 Ga) and Southern Granite Rhyolite Province (1.3-1.4 Ga) were collected from cores and cuttings retrieved during drilling operations. The full suite was analyzed for trace element concentrations, and thirty-nine samples were analyzed for radiogenic isotopes Pb, Sr, and Nd. Present-day Pb isotope ratios of basement rocks create linear trends similar to MVT ore trends and three samples are enriched in radiogenic Pb. Age-corrected Pb isotope ratios reflect the sample Pb signatures at the time of MVT ore deposition, and these ratios plot less similarly to ore Pb signatures. Age-corrected Pb isotope ratios alone suggest the basement rocks and the MVT ores are not genetically related. Present-day ratios are only slightly promising. The three highly radiogenic samples are unique from the rest not only because of their Pb signature but also their enrichment in 87Sr/86Sr and unique enrichment in heavy rare earth elements (HREEs). These data suggest that the basement as a whole did not supply metals to midcontinent MVT ores, but perhaps localized features within the basement such as younger intrusions or igneous dikes supplied the highly radiogenic Pb. The three anomalously enriched samples may represent one of these more local features. This would be consistent with the 1.01 and 1.05 Ga model Pb source ages because the expected age of midcontinent basement is 1.3-1.8 Ga. These new data provide valuable geochemical results to the limited database of southern midcontinent basement, and they have implications for understanding the formation of economic MVT deposits of the southern midcontinent
The School Lunchroom as an Important Context in Children’s Social Development: The Link Between Lunchtime Peer Acceptance and Peer Victimization
No full textSteggerda et al. (2022a) found that children’s self-reported lunchtime peer acceptance was predictive of later experiences of peer victimization. These authors speculated that the link between lunchtime peer acceptance and peer victimization is mediated by children’s internalizing or externalizing problems. The current study adds to the field’s understanding of the link between children’s lunchtime peer acceptance and peer victimization by considering whether internalizing symptoms and externalizing problems are potential mediating variables. Participants were 659 children from 34 classrooms (M age 9.31 years, SD = 0.50; 50.7% female; 42.7% Hispanic/Latinx, 30.3% White, 10% Pacific Islander, 7.8% bi/multiracial, 2.2% American Indian, 2.2% Black, 1.9% Asian, and 2.9% other). I used structural equation modeling (SEM) to test whether internalizing symptoms, externalizing problems, or the combination of these adjustment difficulties mediate the prospective link between lunchtime peer acceptance and peer victimization. I also tested whether pathways among these variables differed by gender, race, and ethnicity. Results indicated that internalizing symptoms consistently mediated the prospective relation between lunchtime peer acceptance and peer victimization. Significant differences in the pattern of findings were found across race and ethnic subgroups. Discussed are potential implications these findings have for school-based interventions for bullied children
Play Therapists Attitudes, Knowledge, and Skills in Identifying Disordered Eating in Children and Adolescents.
Get PDFThe prevalence of disordered eating among children and adolescents has been steadily increasing, posing an increase in the need for treatment. Recognizing and addressing disordered eating in childhood and adolescence is critical to fostering a healthy relationship with food and body image and ensuring the overall well-being of youth. Play has long been considered an important factor in understanding children\u27s lives and experiences and is the recommended counseling approach for children and adolescents (Landreth, 2012). Play therapy is grounded in the fundamental understanding that play is children\u27s and adolescents\u27 natural mode of expression, where toys are their words, and play is their language (Landreth, 2012). The play therapist is a licensed mental health clinician who has received specialized training and education in play therapy (Association for Play Therapy [APT], 2023b). The play therapist is, therefore, considered the most qualified professional to work with children and adolescents presenting with various mental health issues. While play therapists have received specialized education and training in working with children and adolescents (APT, 2023b; 2023c), training and education around disordered eating is not required and often not available. Play therapists serve many roles and share many spaces with youth and are therefore in a unique position to identify risk factors and to provide early intervention. By equipping play therapists with basic knowledge about disordered eating, they will be able to recognize the signs, provide tailored support, and know who to refer to in order to collaborate effectively with other professionals and families. In doing so, youth are offered a safe space to foster a healthy relationship with food and body image. The aim of this dissertation was to better understand play therapists’ attitudes, knowledge, and skills of disordered eating by assessing their knowledge of disordered eating in children and adolescents, their attitudes around disordered eating-related factors, and their perceived skills. The purpose of this study was to evaluate the knowledge, attitudes, and skills in identifying disordered eating patterns in children and adolescents. These findings helped support the need for more intentional training with disordered eating practices in children and adolescents
In-service Needs of Selected Arkansas Agriculture Teachers Related to Precision Agriculture Systems
Get PDFPrecision Agriculture (PA) entails the use of computer technology, including software and hardware, together with good agronomic practices to effectively utilize resources available to growers. PA may enhance profitability, sustainability, resilience, and efficiency when implemented successfully. The aim of this study was to identify, assess, and describe the PA in-service needs of selected high school agriculture teachers in Arkansas. Forty-four teachers participated in the study, recruited through convenience sampling during the annual Arkansas agriculture in-service workshop held at Camp Couchdale in July 2023. A survey instrument was developed, and all forty-four participants provided complete responses. The survey included twenty-nine PA competencies from seven PA technologies, along with selected community characteristics and PA barriers that might hinder teachers from integrating PA into their teaching. All participants perceived the twenty-nine competencies to be significantly important to include for high school instruction but felt their teaching proficiency in these areas was below average. Mean weighted discrepancy scores were used to identify areas requiring in-service training. GIS, soil sensing systems, UAVs, and RTK-GPS emerged as the top priority areas. The study identified barriers preventing participants from integrating PA competencies into their curriculum. The top identified barriers were lack of equipment, lack of curriculum materials, lack of personal PA knowledge and lack of In-service opportunities Additionally, it found significant correlations with community traits, such as growing on a row crop farm or managing, leasing, or owning one and PA in-service training
Identifying Grassland Cores in the Southeast: Relating Spatial Covariance to Avian Communities and Vegetation Structure
Get PDFGlobally, grasslands are declining in range, which is leading to a decline in grassland-dependent taxa. These declines can be attributed to a variety of issues, a major one being the encroachment of woody species into historic grasslands. There is a new framework for strategizing grassland management, referred to as “Defend the Core,” which calls for proactive management of intact grasslands, meaning conserving remaining grasslands by preventing woody encroachment in the first place. To successfully defend the core, it is imperative that we develop rapid methods to identify intact grassland cores for management priority. One method that can be used for identifying grassland cores is identifying and tracking spatial regimes, which can be done using the relatively new metric of spatial covariance. Spatial covariance can measure the degree of coexistence between two vegetative functional groups, essentially quantifying boundaries between two cover types. To identify grassland regimes, or intact grassland cores, we can calculate the spatial covariance between tree cover and grass cover. However, this metric was recently developed, and knowledge gaps remain. This metric has never been tested in grasslands of the southeastern United States and has not been used as a covariate for occupancy probability modeling. Additionally, spatial covariance has never been related to established on-the-ground metrics of vegetation structure. For this thesis, we used the Rangeland Analysis Platform cover data to calculate spatial covariance between tree and grass cover in historic grassland sites across the Mississippi Alluvial Valley and the Arkansas River Valley in central and east Arkansas. These sites have undergone varying management interventions and are highly fragmented in comparison to rangelands of the western US, where spatial covariance has previously been tested. In Chapter I, we related spatial covariance to a variety of established metrics for quantifying vegetation structure. We collected vegetation data at our study sites and used generalized linear models to understand the relationship between each vegetation measurement and spatial covariance. We found that there were no strong relationships between on-the-ground vegetation metrics and spatial covariance, only further emphasizing that spatial covariance is identifying and measuring something that is not captured by many traditional field-collected vegetation metrics. In Chapter II, we used spatial covariance in an occupancy framework to understand avian responses to spatial covariance and boundaries of grassland cores. We used a multi-species occupancy model to predict occupancy probability of the grassland bird community and individual grassland bird species and mapped these results across a known grassland core. We found that all grassland birds included in our models avoided areas with negative spatial covariance, or boundaries between grass and tree cover, and were more likely to occupy intact grassland cores that are free of boundaries. In this thesis, we delve deeper into the recently developed spatial covariance metric. We find that this metric is promising for identifying grassland cores from an avian perspective, which only helps better strategize management and protection of grasslands
Investigation of Optically Pumped GeSn Quantum Well Lasers
Get PDFSilicon photonic integrated circuits enable the capability of producing on-chip processing of photonic signals, including both emission and detection. Emission materials, however, have been limited for monolithic integration due to high processing temperatures, indirect bandgap materials, and material integration complications. The (Si)GeSn material system has recently attracted attention due to the bandgap transition from the Si and Ge, naturally indirect bandgap, to direct bandgap with sufficient Sn incorporation. Additionally, the low growth temperature (CMOS compatible; \u3c400 \u3e°C) of (Si)GeSn materials can enable the monolithic integration of the highly desired mid-infrared light emission on the Si Photonic platform. This dissertation first discusses a study showing improved quantum confinement in a (Si)GeSn quantum well through an increase in barrier height by utilizing SiGeSn materials for the barrier layer. Then an exploration of (Si)GeSn multiple quantum wells (4-, 6-, and 10-QW) helps find a minimum active region thickness necessary for adequate overlap between the active region and the optical mode to produce gain. Following this, the inclusion of capping layers (on top of the GeSn active region) in the (Si)GeSn layer structure increases the overlap between the optical mode and the active region of the layer structures. Finally, a dual-wavelength single-cavity (Si)GeSn laser is produced through appropriate quantum confinement in the well regions of the layer structure, sufficient optical mode overlap with the active region, and optical mode overlap with a lower layer which is also capable of laser emissions. The dual-wavelength operation is enabled due to the Fermi-level splitting of the band structure between the layers which are producing the lasing. Through these various material and device studies, the production of a single laser cavity capable of producing multiple emissions can extend the sensing capabilities of a single photonic circuit while also minimizing the necessary footprint. With applications such as gas and biological sensing, data communications, and light detection and ranging (LiDAR) systems, the (Si)GeSn material system has the capability to produce low-cost, high-yield, modules to improve the state of the art for monolithic Silicon Photonic Integrated light sources of the future
Student Perceptions and Academic Performance when Taught with Multiple Active Learning Methods in a High Enrollment Undergraduate Human Physiology Course
Get PDFWhen instructing very large groups of students in science, it can be difficult to engage all students in the content and measure their understanding. A major unaddressed challenge in science instruction is how specifically to design and implement strategies that engender active learning particularly in high-enrollment undergraduate courses. Active learning, which represents a diverse set of strategies, may include student engagement as part of instruction through discussions, active movement, and application (Bernstein, 2018; Cavanagh, et al. 2016; Michael, 2006 & Wilke, 2003). This study was designed to provide data addressing the gap in the literature regarding how the continual implementation of several active learning strategies in a large enrollment undergraduate Human Physiology class impacts students. I chose three active learning modalities for this study from Bernstein (2018) -- kinesthetic and movement, discussion, and problem-based learning and assigned each to units of study during the semester on a rotating basis so that the learning modality not the unit of study could be studied. This project specifically targeted students’ perceptions of learning through the three modalities and students’ retention of targeted content in Human Physiology. Students responded to an end of semester survey and evaluation on how their learning was impacted. A second research component analyzed students’ performance on summative exams under different active learning modalities to provide a comparative analysis across modalities and duration of the study. I found that students were overwhelmingly positive toward participating in these active learning environments and found these activities to be enjoyable and improve cognizance. In survey responses, students reported that active learning improved their knowledge retention and confidence in understanding the content. Students enjoyed and retained information and improved content retention leading to improved examination performance when taught with kinesthetic methods