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Crypto Commerce Comes to Texas: Making Texas Commercial Law More Competitive in the Digital Asset Economy
Get PDFAs crypto and blockchain-related activity continues growing in Texas, legislative efforts are underway to create a more favorable legal environment. Legal reforms, including the 2022 amendments to the Uniform Commercial Code (UCC) Article 12, enable the creation of "controllable electronic records" that we argue in a recent law review article1 can represent claims in bankruptcy by trade creditors ��� typically suppliers, contractors, and customers who have little ability to sell their distressed debt claims under current legal rules. By tokenizing these claims on blockchains as "debt tokens," the claims can be freely traded with legal certainty, increasing liquidity. Adopting UCC Article 12 would therefore make Texas an attractive jurisdiction for this kind of claims trading in the digital asset economy.Mosbacher Institute of Trade, Economics, and Public Polic
Analysis and Development of Novel Space Domain Awareness Algorithms in the Lunar Domain
No full textSpace domain awareness (SDA) is a current hot topic in the astronautical engineering community. Dealing with the study and monitoring of objects orbiting around the Earth, there is a new push to extend SDA methodologies to accommodate the cislunar domain and beyond to the lunar domain. Analysis of legacy and development of new SDA methods is of great interest for many upcoming space missions. Orbital maneuver planning, objecting tracking, and dynamic modeling are all coupled to the advancement of SDA methodologies.
This work investigates current and develops new Lunar SDA models and algorithms lying within three categories: optimal orbit transfers, the spherical harmonic gravity (SHG) field representation, and orbit determination through batch/sequential processes. Optimal bi-impulse orbit transfers are utilized to realize bang-bang fuel-optimal transfer solutions. A method to select a truncated model degree of an SHG field representation with respect to the total model uncertainty for a given orbit and spatial location is presented. The sensitivity of the traditional Lunar orbit determination (OD) algorithm utilizing Earth-based ground observations with reference to observational considerations is investigated. Gooding���s angles-only OD method is modified to perform Lunar satellite-to-satellite OD and is improved by accounting for observer uncertainty. Finally, a new modification to the Kalman filter is derived to restrict the state estimate and covariance updates
Direct Ink Writing of Polymeric Materials for Advanced Applications
No full text3D printing (3DP) has gained interest in recent decades for forming custom structures with complex geometries which are not readily produced by traditional manufacturing techniques. This advance in manufacturing processes must coincide with the development of appropriate materials. This dissertation focuses on the design of high-performance materials for the extrusion-based 3DP method of direct ink writing (DIW). Feedstock inks for DIW must be viscous, shear-thinning, and thixotropic to hold their shape after extrusion and solidify into monolithic structures. To achieve these rheological requirements, two approaches were taken: 1) liquidous polymers were combined with a variety of particle fillers to produce paste-like composites and 2) mild heat treatment facilitated the gelation of a polymer sol to create a printable ink.
Through the above approaches, a library of inks spanning thermal energy regulation, tunable porosity, hybrid solid-liquid structures, and ultralightweight thermal insulators have been developed. The rheology, microstructure, mechanical properties, and end use performance of these inks were evaluated, and the printed objects were found to be effective at their target tasks. For example, the thermal energy regulating ink maintained a 40% lower temperature than the internal environment when heated. The porous materials had controllable mechanical properties, with elastic moduli ranging from 3.4 to 25.4 MPa depending on the porosity level. Fluid-containing structures had tunable microstructures, thus providing a modular platform for incorporating functional liquids into monolithic printed parts. Finally, printed ultralightweight polyimide aerogels possessed similar low densities, high surface areas, and thermal insulation capabilities to traditional cast aerogels, demonstrating potential use as bespoke thermal insulators for electronics on air and spacecraft. This library of materials paired with future directions in ink standardization will propel the approachable technique of DIW into advanced applications
Determining Stream Fish Trait-Environment Relationships across Systems, Scales, and Forms of Alteration
Get PDFFreshwater ecosystems are under increasing threat from the growing human population and its demand for freshwater resources. River basins are increasingly fragmented by reservoirs and low head dams as well as growing urban developments and land use change. Interests in conserving and restoring these systems is growing as understanding of the importance of their diversity and the ecological services that they provide becomes more widely spread. Ecological integrity assessments and ecological models are used to inform management and restoration efforts around the world. These models typically rely on taxonomic information or single species inputs; however, including more trait-based approaches would allow managers to make better informed decisions across species and at the community level. My thesis presents a generalizable and modular framework for incorporating trait-environment relationships as well as traits themselves into methodologies for future ecological integrity assessment frameworks and restoration planning. With regard to using traits to inform ecological integrity assessments, my results identified six functional traits that were consistently responsive across three forms of anthropogenic alterations to rivers. The consistency in the directionality of four out of the six trait relationships further supports their inclusion as indicators of stream alteration. Further, in terms of informing ecological models used for restoration, my results identified three significant relationships between morphological traits and mesohabitat variables related to stream hydraulics. These relationships were identified using fish community data that were collected across gradients of stream size, climate, and degree of alteration, thus supporting their potential as general structuring principles within stream fish communities. By analyzing stream fish traits and their potential relationships to anthropogenic alterations and natural environmental gradients, I demonstrated the importance and benefits of incorporating traits into future stream conservation, restoration, and management
The Effects of Pishing and Playback on Avian Fitness
Get PDFPlayback and pishing are auditory stimuli used by researchers, tour guides, and amateur birders to facilitate viewing or detection of a bird. Playback, playing recordings of territorial songs or contact calls, and pishing, making a small, repetitive noise, stimulate a territorial or defensive response. Previous studies have found an increase in vocalization and reduction of self-maintenance, foraging, and movement behaviors in birds exposed to pishing and playback. Concerns have been raised about potential negative impacts of playback and pishing on avian long-term fitness, as a result of the behavioral shifts caused by these techniques. We studied the effects of pishing and playback on behavior of wintering and breeding birds in College Station, TX. Pishing and playback treatments were administered for five minutes in sets of five days with two day rest periods for four weeks. Behaviors were noted at 30 instantaneous intervals before, during, and after treatment for 45 minutes of observation. Behaviors noted were singing, calling, chasing, perch-hopping, flying, perching, foraging, and displaying. Species and distances of birds were noted. Analysis of the breeding season data shows that birds vocalized more during the treatment, but there was no significant difference in the post-treatment period. This indicates that behavioral shifts lasted less than fifteen minutes after exposure to pishing and playback. The results of this study will be able to guide regulations about the use of playback and pishing, an ever-increasing concern as the popularity of birding increases
Farmworkers as Heroes for COVID-19 Mitigation: Curriculum Development, Implementation, and Evaluation of S�� el H��roe (Be the Hero)
Get PDFMigrant and Seasonal Farmworkers (MSFW) are at heightened vulnerability for SARS-CoV-2 infection and transmission due to their occupational and lifestyle exposure. Furthermore, the high levels of chronic illnesses among the MSFW community also contribute to their vulnerability. The purpose of S�� el H��roe is to create a culturally and linguistically responsive outreach program by developing, deploying, evaluating, and disseminating a curriculum with the goal of mitigating the infection and transmission of SARS-CoV-2. The program seeks to do this by providing the necessary tools and knowledge to MSFWs to gain the necessary knowledge, skills, attitude, and self-efficacy to promote adoption of positive mitigation behaviors. In order to execute the purpose of the S�� el H��roe outreach program a formative evaluation for curriculum development was conducted, pilot testing then followed in which further modifications were identified to ensure program success, and finally program implementation. The expected outcomes are 1) Address limitations in risk mitigation literacy and build capacity of a hard-to-reach population (i.e., MSFW), 2) encourage MSFWs to make appropriate decisions to reduce the risk for infection and transmission of SARS-CoV-2, 3) strengthen CHW/P understanding of SARS-CoV-2 and the practice to mitigate infection, 4) promote positive behavioral changes in family risk mitigation behaviors, and 5) empower community residents with added skills and knowledge! Additionally, the S�� el H��roe outreach curriculum program can provide insight on the importance and effectiveness of creating a program that takes into consideration the culture and language of the target community
