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Predictive Analysis of Defense Language Proficiency Test Outcomes: A Comparative Study Using Neural Networks and Logistic Regression
No full textExcerpt: Proficiency in foreign languages is crucial for effective global operations, and proficiency can be gained from training courses. In this work, we study the influence of various training courses by analyzing a 9,436-row dataset, including factors such as language, test timing, and their effect on an individual\u27s language test performance
Empirical Comparison of Shadow Imagery Resolution Advantages from Multispectral Image Stacking
No full textStructural Index Parameter for Capturing Structural & Aerothermal Effects in Conceptual Level Vehicle Design
No full textThe three phases of vehicle conceptual design include parametric sizing, configuration layout, and configuration evaluation. During the parametric sizing phase, the ability to define and quantify the technology level of an aerospace system allows the assessment of candidate designs based on feasibility given current technology or indicates if one must advance a particular technology. To meet this need, the structural Index (Istr) parameter merits exploration to consider structural and aerothermal effects during the parametric sizing phase of conceptual design given materials, structural concepts, and manufacturing capability. This study showcases the utility of this structural/materials technology parameter for high-speed vehicles by modernizing and expanding upon Paul Czysz\u27s original structural index (Istr) versus the surface temperature map. The modernized and expanded structural index (Istr) map is constructed by selecting a temperature-through-thickness method for a given thermal protection system (TPS) that simplifies a given surface temperature and atmospheric pressure profile into a constant heat pulse. One can then size the TPS to keep the structural temperature within material limits. The newly generated structural index (Istr) maps allow one to observe trends with variations in surface temperature, cruise time, average atmospheric pressure (Pavg), and TPS materials
Sensitivity Analysis of LEV Trajectory and Surface Separation to Discrete Jet Design Parameters
No full textThis paper presents results of a parametric investigation on leading-edge vortex (LEV) trajectory and separation control sensitivity to a recessed discrete jet’s location, orientation, and size when actuated at momentum coefficient ≤ 0.02 on a rounded leading-edge, 45 degree swept, cropped delta wing in incompressible flow. The study determined that the maximum spanwise displacement of the LEV separation point, and thus maximum recovery of the attached flow region, required minimum momentum and mass flow when the jet was located immediately downstream of and near-aligned with the laminar separation bubble reattachment line. Once optimally placed, the spanwise extent of LEV separation displacement is a function of momentum and mass flow, and greater momentum is required to achieve a prescribed spanwise displacement at greater angles of attack
Undergraduate Pacific Studies Exam Generation and Answering Using Retrieval Augmented Generation and Large Language Models
No full textThe capabilities of large language models have increased to the point where entire textbooks can be queried using retrieval-augmented generation (RAG). The study evaluates the ability of OpenAI’s ChatGPT-3.5-Turbo and ChatGPT-4-Turbo models to create and answer exam questions based on an undergraduate textbook. 14 exams were created with true-false, multiple-choice, and short-answer questions from a textbook available online. The accuracy of the models in answering these questions is assessed both with and without access to the source material. Performance was evaluated using text-similarity metrics including ROUGE-1, cosine similarity, and word embeddings. 56 exam scores were analyzed to find that RAG-assisted models outperformed those without access to the textbook, and that ChatGPT-4-Turbo was more accurate than ChatGPT-3.5-Turbo on nearly all exams. The findings demonstrate the potential of generative artificial intelligence tools in academic assessments and provide insights into comparative performance of these models
A Standardized Methodology for Evaluating a Digital Badging System [ Data Package ]
Get PDFDigital badges, a form of micro-credentials, have grown in popularity over the past decade. However, few standard processes exist to assess the potential of digital badging systems within an organization. This study proposes a generalizable methodology for comparing a badging system with other methods of recording skills and competencies. The experimental design is tested using the military\u27s cyber operations community as the target organization. Finally, mixed-method data from thirty-six participants is analyzed in accordance with the methodology. Based on the results, digital badging systems are perceived to be more valuable and usable than a current method of military talent management. This approach supports efforts to enhance formal and informal learning, competency-based learning, granular decision-making, and to build trustworthy systems of record
Recombobulate correction method for oscillating scene change artifacts in longwave infrared Fourier transform spectroscopy spectra
No full textCalibration of high-temperature Fourier transform infrared spectrometer data with low-temperature calibration measurements
No full textFourier-transform (FT) spectrometer data must be calibrated using at least two reference sources to yield a target temperature. An experiment was performed with an ABB MR304 FTIR spectrometer to determine the best calibration method for data from its MCT (mercury–cadmium–telluride) and InSb (indium–antimonide) detectors at temperatures well above the reference temperatures (extrapolation), as well as to analyze the effects of mesh screens on the detector behavior and calibration quality. Four datasets were collected and plotted on radiance versus instrument response plots to analyze the detector behaviors and to test how well lower temperature points predicted higher temperature points with linear and quadratic fitting. It was determined that the MCT detector is quadratic for low wavenumbers at a low signal but otherwise linear, and that the InSb detector is linear for all wavenumbers. It was concluded that (1) mesh screens have a detrimental effect on calibration quality and (2) linear calibration is the better method for calibration, including extrapolation
Fatima-GB: Searching Clarity within Marine Fog
No full textFog constitutes a thick, opaque blanket of air hugging Earth’s surface, laden with small water droplets or ice crystals. Fog disrupts transportation, poses security threats, disorients human perception, and impacts communications and ecosystems. Collusion of atmospheric, terrestrial, and hydrologic processes produces fog droplets that pullulate over hygroscopic aerosols that act as condensation nuclei. Marine fog is particularly complex, since underlying dynamic, thermodynamic, and (bio)physicochemical processes span fifteen decades of spatial scales, from megameter-sized synoptic weather systems to nanometer-scale bioaerosols. This paper overviews the first international field campaign [Fog and Turbulence Interactions in the Marine Atmosphere-Grand Banks campaign (Fatima-GB)] of the project dubbed Fatima conducted during 1–31 July 2022 in the Grand Banks region of the North Atlantic. Therein, weather systems and commingling cold and warm oceanic waters provide entrée for fog genesis. Measurement platforms included an islet southwest of Nova Scotia (Sable Island), a research vessel ( Atlantic Condor ), an offshore oil platform, and autonomous surface vehicles. The instrument array comprised of extant remote and in situ sensors augmented by novel sensing systems prototyped and deployed in marine fog to penetrate the smallest scales of turbulence, examine aerosols, and quantify radiation budget. The comprehensive dataset so gathered, together with satellite and reanalysis products, mesoscale model, and large-eddy simulations, demonstrated that the long-held hypotheses of marine fog formation by warm air advection over colder water and in areas of enhanced (shelf) turbulence need to be revisited. The study also elicited new phenomena, for example, the fog shadow (clearings of fog downstream of islands)