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Dynamics of Rotating 2D Ellipse in Stratified Flow
Get PDFSubmersible vehicles that move through seawater are subjected to a variety of effects. Seawater has a non-uniform density because of uneven heating and the tendency of dense saltwater to sink. This non-uniform density distribution induced by gravity is known as stratification and introduces vertical confinement and internal gravity waves to flows around bodies. Along with translational motion, these vehicles also perform rotational motion. To identify the effects of density gradient, body shape, and rotation on the flow, 2D direct numerical simulations (DNS) are run and analyzed. The simulations are conducted using the open-source CFD solver Nek5000, utilizing its overset-grid-based methodology. The results show previously unreported patterns of drag and lift acting on rotating bodies, and show the regime when rotating motion of the ellipse results in formation of internal gravity waves
\u3ci\u3eSo Much Cooler Online\u3c/i\u3e: Social Media Usage by Agricultural Educators in Secondary SBAE Classrooms
Get PDFSocial media has become a powerful tool in education, helping teachers connect with students and share information in new ways. Agricultural educators are using platforms like Facebook and Instagram to promote agricultural literacy and engage students in an online format. This study explores how high school agriculture teachers use social media, what challenges they face, and how comfortable they are using it. Through an online survey and analysis of social media engagement data, this research highlights the benefits and personal evaluation educators have when using these platforms. The results show that while social media helps teachers share resources and connect with students, online community engagement highlight an overwhelmingly positive sentiment towards posts about agricultural education. This research offers valuable insights for educators, schools, and policymakers on how to better support teachers in using social media effectively while addressing potential challenges
Mapping and Examining Recreation in Indian Creek, Bears Ears National Monument
No full textRecreation is growing in desert areas of the western United States, and mapping the expansion of these activities is vital to management and conservation efforts. Desert ecosystems provide many critical ecosystem services, including carbon storage, and the growing popularity of outdoor recreation in Western US desert regions poses a threat to these ecosystems. Unregulated recreational activities can harm desert plant and soil health, including the functioning of biological soil crusts. This research project focuses on mapping several types of popular recreational activities in order to monitor and evaluate the impact of these activities within the Indian Creek areas of Bears Ears National Monument. Mapping the presence of recreational activities is critical for devising effective conservation strategies and promoting sustainable land use in desert ecosystems. Comprehensive maps of foot trails, climbing routes, motorized off-roading trails, and campsites were created using a combination of data from recreation websites, satellite imagery, privately shared data from mapping organizations, and in-situ data collection. A literature review detailing the impacts of each of these types of recreation on desert ecosystem functioning was also performed. After quantifying and mapping all recreation in Indian Creek, researchers selected 30 study sites using these data. These study sites were later used in a more comprehensive study of the impacts of each type of recreation on desert soils and vegetation. A model of soil erosion risk in Indian Creek was also created using the Revised Universal Soil Loss Equation, and this model was visualized as a map. Satellite imagery was also used to calculate and display average vegetation loss in the area from 2015-2021
Modeling and Optimization of METS: An Enveloping Tensegrity Structure for Adaptive Stiffness Control in Space Applications
No full textTensegrity structures, defined by rigid elements in compression balanced by tensioned members, offer lightweight, flexible solutions for adaptive space systems. Stiffness modulation is vital for space applications, such as reinforcing robotic arms, stabilizing astronaut suits, and supporting deployable structures in microgravity. Traditional systems often rely on heavy actuators or rigid components, limiting adaptability and increasing mass. This research presents the Multi-Stiffness Expandable Tensegrity Structure (METS), an enveloping tensegrity system designed to conform to spacecraft appendages and provide tunable stiffness without external power. Using control string actuation and unit cell optimization, METS achieves scalability and adaptability, validated through modeling, innovation, and experiments targeting a 15% stiffness increase. This work advances lightweight, passive structures for NASA missions
Multi-Point Fabrication of Terahertz Metal Mesh Filters
No full textA metal mesh filter is fabricated by creating metallic squares on a dielectric substrate. This capacitive metallic filter is fabricated using direct write laser ablation consisting of a femtosecond laser in combination with a high numerical aperture objective. A multipoint fabrication approach is employed by using a holographic beam splitter element to split the beams into several identical gaussian beams. The transmission and reflection characteristics are discussed
A Novel Modular Spherical Joint for Truss Robots
No full textTruss robots and structures are beneficial for lunar missions because of their high strength-to-mass ratio. Even better are robots and structures that are highly modular, allowing the same materials to be rearranged to perform various tasks. The joints of these robots are what must be connected and disconnected to create different truss forms. Therefore, it is necessary to develop highly mobile, modular spherical joints that allow multiple truss elements to attach. Moreover, these joints must be resistant to the lunar regolith. Our contribution in this paper is the design of a new spherical joint and its application to an isoperimetric robot
Solvent Variability With Gold and Silver Nanoparticle Production Using Reverse Micelles
No full textThe synthesis of nanoparticle using reverse micelles is increasing in versatility, popularity, and effectivity. Nanoparticles have unique characteristics including a strong antimicrobial trait that can be effective and sterilizations and decomposition of microbes. Gold and silver have been effective as the ions used in the synthesis of such nanoparticles and have been successful for testing different solvent concentrations and production. Research has shown that different structures and sizes of nanoparticles are efficient at accomplishing different objective, however, trends show that the smaller the nanoparticle, the more efficient a nanoparticle is at fighting microbes
Potential of Genetic Modification in Brine Shrimp for Biotechnological Applications
No full textBrine shrimp (Artemia salina) are hardy organisms capable of surviving extreme environmental conditions, making them an ideal candidate for genetic modification in biotechnological research. This study investigates the potential of genetically modifying brine shrimp to unlock new possibilities in biotechnology. By integrating foreign genes into their genome, we explore how genetic engineering can enhance their adaptability, stress tolerance, and overall viability, providing opportunities for novel applications in fields such as environmental monitoring, bioengineering, and sustainable aquaculture. Our findings highlight the promise of brine shrimp as a versatile and sustainable platform for genetic modification, opening doors to innovative approaches in biotechnology that leverage the unique biology of these organisms
Mapping X-Ray Binaries Across the Milky Way With eROSITA and Gaia
No full texteROSITA is an X-ray telescope array on board the Spectrum-Roentgen-Gamma spacecraft, in a halo orbit around the L2 point. eROSITA is equipped with seven Wolter-1 mirror modules with each module containing 54 nested mirror shells for increased sensitivity1. The main mission for eROSITA is to perform the first all sky survey in the medium X-ray band, about 0.2-8 keV, over a 7-year duration period accompanied by three planned data releases, the first of which was published in early 2024. The eROSITA data release is, to date, the most detailed and sensitive all-sky X-ray survey ever completed, providing stunning views of the sky in X-rays and nearly 1 million distinct X-ray sources2
Astrometric Measurements of WDS 12115+5325 STF 1608 AB
No full textStar systems gravitationally bound to one another offer valuable insights into stellar properties through orbital analysis. Developing binary star orbits provides information to determine stellar masses.