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Method for Target Detection in a High Noise Environment Through Frequency Analysis Using an Event-Based Vision Sensor
No full textEvent-based vision sensors (EVSs), often referred to as neuromorphic cameras, operate by responding to changes in brightness on a pixel-by-pixel basis. In contrast, traditional framing cameras employ some fixed sampling interval where integrated intensity is read off the entire focal plane at once. Similar to traditional cameras, EVSs can suffer loss of sensitivity through scenes with high intensity and dynamic clutter, reducing the ability to see points of interest through traditional event processing means. This paper describes a method to reduce the negative impacts of these types of EVS clutter and enable more robust target detection through the use of individual pixel frequency analysis, background suppression, and statistical filtering. Additionally, issues found in normal frequency analysis such as phase differences between sources, aliasing, and spectral leakage are less relevant in this method. The statistical filtering simply determines what pixels have significant frequency content after the background suppression instead of focusing on the actual frequencies in the scene. Initial testing on simulated data demonstrates a proof of concept for this method, which reduces artificial scene noise and enables improved target detection
Piezoelectric Energy Harvesting from Roadways: Challenges, Advances, and Future Directions
No full textAs the global demand for renewable energy intensifies, piezoelectric energy harvesting from roadways has emerged as a promising avenue for sustainable power generation. This systematic literature review analyzes 61 peer-reviewed studies to assess the feasibility, performance, and potential of integrating piezoelectric systems into roadway infrastructure. While technology faces challenges, such as high installation costs, limited energy output, and a scarcity of thorough economic evaluations, findings suggest it holds considerable promise as a supplementary renewable energy source. The review analyzes the operational characteristics and efficiencies of various piezoelectric transducers, identifies key factors influencing system performance, and evaluates recent technological advances. It further considers the broader socioenvironmental implications of deploying such systems, including potential benefits for green infrastructure development and urban sustainability. Spanning two decades of research, this study highlights the transformative potential of piezoelectric technology in reshaping energy infrastructure. It emphasizes the need for continued interdisciplinary research, particularly in improving system efficiency, reducing costs, and evaluating long-term economic and environmental impacts. By identifying critical research gaps and proposing future directions, this review provides a foundational reference for engineers, policymakers, and researchers focused on sustainable infrastructure and innovative energy solutions
Life-Cycle Cost Analysis of Piezoelectric Energy Harvesters for Roadway Applications
No full textNumerous studies have explored the feasibility of piezoelectric energy harvesters as a renewable energy source within roadways. However, only a few have examined their cost effectiveness, despite the clear need for such an evaluation to determine the viability of large-scale implementation. This research aims to fill this gap by assessing the economic feasibility of integrating piezoelectric energy-harvesting technology into road infrastructure. A dynamic model is developed to estimate the total electrical energy output based on specific traffic conditions and harvester characteristics. This energy output is then used to conduct a life-cycle cost analysis (LCCA) and other key economic evaluations. Additionally, a sensitivity analysis is performed on four different piezoelectric prototypes identified from the literature to determine the impact of various parameters on system viability. The findings provide insights into the economic sustainability of piezoelectric energy harvesters, highlighting key cost drivers and areas for future improvement in system design and material selection
Multivariate probability of detection modeling including categorical variables and higher-order response models
No full textThis paper presents a methodology for extending probability of detection (POD) modeling for continuously valued (â vs. a) signal responses to allow for the addition of multiple variables beyond the simple discontinuity size model, along with higher-level interactions. The statistical methodology for correctly transforming these more complex linear models into POD curves is provided, and the approach is illustrated with a simulated dataset that includes polynomial and categorical predictors
PiCi for Stripline
No full textHistorically, the Thru-Reflect-Line (TRL) method for complex permittivity and permeability extraction has been sufficient in producing accurate and cost-effective measurements of material characteristics. However, this method requires rigorous setup for accuracy and more time to collect all necessary data samples. The Position-Insensitive and Calibration-Independent (PiCi) method for complex permittivity extraction offers an alternative method that is quicker and simpler, requiring less time and only two measurements - sample and line - instead of the TRL method\u27s four - thru, line, reflect, and sample. This method is currently limited to coaxial line and rectangular waveguides only. This paper extends the PiCi method to stripline using unique functions in the Newton-Raphson root search algorithm different from the functions used to characterize the waveguide and coaxial line parameters. The results show the stripline provides an accurate estimation of the material\u27s permittivity and permeability without adjusting for detector mismatch within the network analyzer. Further, detector mismatch correction provides improved stability at all frequencies of observation and increased precision at a sufficiently high frequency. Thus, this research validates another comparable method to the PiCi method for material characteristic extraction for the waveguide and coaxial line, further reducing measurement time and improving cost effectiveness. Abstract © AMTA
AFIT Generative AI Teaching Guidebook Synopsis
Full text linkThe main objective of this work was to bring together various perspectives on how to envision incorporating Gen AI capabilities into the learning environment and identify some best practices for their implementation. Any instructor who is interested in these capabilities but does not necessarily have a technical background can find pragmatic use of the examples provided. While the examples have a wide range of applicability, they are meant to serve as a starting point for educators to explore what would be beneficial to their educational environment, from traditional classroom settings to online continuing education courses
Radon–Hurwitz Grassmannian codes
No full textEvery equi-isoclinic tight fusion frame (EITFF) is a type of optimal code in a Grassmannian, consisting of subspaces of a finite-dimensional Hilbert space for which the smallest principal angle between any pair of them is as large as possible. EITFFs yield dictionaries with minimal block coherence and so are ideal for certain types of compressed sensing. By refining classical work of Lemmens and Seidel based on Radon-Hurwitz theory, we fully characterize EITFFs in the special case where the dimension of the subspaces is exactly one-half of that of the ambient space. We moreover show that each such Radon-Hurwitz EITFF is highly symmetric, where every even permutation is an automorphism
Convergent close-coupling approach to electron scattering on H\u3csub\u3e3\u3c/sub\u3e\u3csup\u3e+\u3c/sup\u3e : Scattering dynamics and dissociative processes
No full textCross sections for electron impact dissociative excitation and ionization in scattering on vibrationally excited levels of the ground electronic state of H3+, D3+, and T3+ are reported in the energy range of 8–1000 eV. Calculations have been performed using a newly developed version of the molecular convergent close-coupling code. Convergence of the cross sections with the size of the projectile partial-wave and close-coupling expansions is examined. Branching ratios and cross sections for the yields of D2+ and D+ from dissociative excitation of D3+ are presented and isotope effects are investigated. Cross sections for total dissociative ionization yielding atomic fragments such as D+ are presented and the total inelastic cross section is produced. Good agreement with available experiments has been demonstrated
Impact of Prior Exposures on Biomarkers of Blast during Military Tactical Training
No full textBlast injuries and subclinical effects are of significant concern among those Service Members (SMs) participating in military operations and tactical trainings. Studies of SMs repeatedly exposed during training find concussion-like symptomology with transient decrements in neurocognitive performance, and alterations in blood biomarkers. How prior mild TBI (mTBI) history interacts with low-level blast (LLB) exposure, however, remains unexplored, which we investigate in the present study, to identify interindividual biomarker changes from LLB exposures influenced by prior history of mTBI