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Atlas of AI: Power, Politics and the Planetary Costs of Artificial Intelligence - Book Review
No full textAn Evaluation of the Relationship Between Beef Cattle Grazing Activity Traits and Conception Methods During the Breeding Season
No full textEfficient use of native rangelands and improved reproductive success are primary objectives in beef cattle production. Grazing behavior during the breeding season may be influenced by pasture characteristics, including size and water availability, as well as physiological differences due to reproductive status. This study aimed to evaluate the relationship between grazing activity and conception method in crossbred Angus cows over a 2-year period. The study was conducted during the winter months (December – February) on the Central Coast of California with a mean temperate of 53 degrees Fahrenheit. Cows (n = 76) were blocked by age and then randomly assigned to be fitted with a Knight GPS tracking collar. All cows, except first-calf heifers (n = 12), were synchronized for fixed-timed artificial insemination (FTAI) and bulls were turned out 7 d after for a 65 d breeding season. Cattle were managed in an intensive rotational grazing system (n = 36; mean size: 22.13 ± 13.53 ha). Cows were retrospectively classified into the following groups: conception to FTAI (AI; n = 23), natural service (Bull; n = 37), and non-pregnant (Open; n = 16). Average daily distance traveled (km/d) and elevation gain (m/d) were measured at 10 minutes intervals. Data were analyzed using the MIXED procedure in SAS 9.4, including the main effects of conception method, number of water sources, pasture size and their interactions. Pasture size was retroactively classified as Small (n = 11, mean = 26 acres), Medium (n = 15, mean = 51.60), or Large (n = 7, mean = 115.14). Daily distance traveled, and elevation gain exhibited a conception method × water source × pasture size interaction (P \u3c 0.001). AI-bred cows traveled the greatest distance in large and small pastures with only one water source available (P \u3c 0.001). In contrast, Open cows exhibited the greatest distance traveled when two water sources were available (P \u3c 0.001). In medium pastures, regardless of water source availability, distance traveled was comparable across conception methods (P ≥ 0.697). Open cows in large pastures with two water sources gained the most elevation (P \u3c 0.001). Elevation gain was more evenly distributed across conception methods in small pastures (P ≥ 0.998). Regardless of pasture size, AI cows exhibited greater elevation gain when only one water source was available (P \u3c 0.001). Bull bred cows were generally intermediate in daily distance compared with AI and Open groups, tended to show fewer extreme daily values, and concentrated activity more in lower elevation, central areas near water. By strategically managing pasture resources in the context of conception method then producers can increase grazing distribution in native rangelands to ensure continued sustainability
Analysis and Evaluation of Backtracking Settings for Energy Yield Optimization at the Cal Poly Solar Farm
No full textThe Cal Poly Solar farm has been built as a single axis tracking facility with two different types of panels. Both conventional single cell solar panels and twin cell solar cells have been used in its construction. Twin Cell panels typically perform better than their conventional counterparts when shaded by other panels in the row in front of them in a fixed tilt system. However neither module performs well when even a small portion is shaded. This project will access the system API to access data for the field and process to determine the energy yield improvements that can be made by optimizing backtracking settings for each array in the Cal Poly Solar Farm. Backtracking is a technique where the single axis tracker avoids shading other rows by sub-optimally tracking the sun until it is high enough in the sky that this is not necessary. This is relatively straightforward in a field that is flat or at least has all controlled modules in the same array. However the Cal Poly Solar farm installation has significant variation in terrain and this was transferred to the modules in adjacent rows such that they are not in the same plane nor are they parallel. As a result there is significant error in the backtracking algorithm that was not designed for this case which is seen by significant power losses in both of the types of panels. The subject of this research project is to determine the improvements that can be made in energy yield by adjustment of the backtracking settings for each array. The parameters have been adjusted and we will need to determine the change in daily energy yield that is achieved for all 12 trackers. This is extremely time intensive and we will be using automation to implement the calculations and comparisons, likely through use of Python. I have obtained access to allow data acquisition for power and energy data and operation of the tracking system at the Cal Poly Goldtree Solar Farm to allow this project to be completed 100% remotely if necessary. All control and data collection can be accomplished via a web based dashboard that allows us to monitor the performance of the farm in real time and to collect data that can be analyzed to determine the improvements
Seismic Resilience of Timber Structures
No full textWood houses dominate the construction landscape in the United States (U.S.), with over 94% of new homes constructed in 2022 being wood framed. New Zealand shares a similar construction landscape, with building practices for wood houses like those in California. Nevertheless, the 2010-2011 Canterbury earthquake sequence damaged nearly three quarters of the housing stock in the region. A total of 150,000 homes were damaged, with about one fifth exceeding NZ$100,000 in damage. To assess the likelihood of economic losses of California’s timber houses, a shake table testing campaign is underway at the California Polytechnic State University Advanced Technology Laboratory in San Luis Obispo. A full-scale, two-story timber specimen—designed with typical light-frame construction details—is being tested with representative nonstructural components, including windows, doors, and sliding doors. This project will provide experimental evidence of earthquake-induced economic losses in timber houses and serve as a foundation for developing mitigation strategies to reduce the economic impact on our society of future earthquake events
Refurbishing and Deploying Oceanographic Equipment
No full textIn this SURP project, a student will help catalog, refurbish, test, and then deploy oceanographic equipment into Morro Bay and nearby coastal regions. In 2024, the Talke lab inherited approximately $300-400k of oceanographic equipment (sticker price) that was originally bought between 2000-2020. Instruments include multiple pressure gauges, velocity instruments, salinity-temperature-turbidity gauges, particle sizers, and a sonar for making bathymetric measurements. Help is needed to check (“talk to”) these instruments, determine which still work, and then field deploy them into the central coast., For some instruments, additional hardware (batteries, cables) and communication adapters may be needed. Because instrument software is often old, emulation of older operating systems or DOS may be required to establish communication. Testing will first take place in a lab, then in Morro Bay. Measurements will be post-processed using software such as Matlab and compared to independent measurements to make sure they are accurate. If these instruments can be made to work again, it greatly increases the ability of Cal-Poly to make physical oceanographic measurements in the coastal zone, both for teaching and research purposes. Desired qualifications include experience with instrumentation, field work, and computer programming, and a willingness to learn-by-doing, to come up with solutions, and to implement them
Development and Test of an Automatic Mass Balancing System for Cal Poly\u27s Spacecraft Attitude Dynamics Simulator
No full textThe Cal Poly Spacecraft Attitude Dynamics Simulator (SADS) is an ongoing project to develop an air-bearing platform capable of recreating on-orbit rotational dynamics with near frictionless and torque-free rotations. However, any offset between the platform\u27s center of rotation and its center of mass will introduce a torque due to gravity.
This thesis presents the design, implementation, and experimental evaluation of a low-cost, automatic mass balancing system for the SADS to address this challenge. A new modular sliding mass system was developed that overcomes issues faced in previous iterations of the SADS, providing real-time positional control of the masses and a customizable center of mass envelope. An STM32-based onboard computer was developed that implements control laws, balancing algorithms, and attitude estimation using a combination of Simulink code generation and C/C++ drivers. A variety of balancing methods found in the literature are tested experimentally, including active feedback control, least-squares batch estimation, and Kalman filtering. The best balancing results are obtained using a PID controller to compensate for the horizontal imbalance, and an unscented Kalman filter for the vertical imbalance. This approach reduces the torque due to gravity to the order of 1x10^-4 Nm, which aligns with results achieved by comparable simulators at other universities. This work also contributes to the literature by demonstrating an experimental PID-based balancing approach and benchmarking its performance against alternative methods
Critical Prison Studies in Dialogue: Abolition-Feminist Pedagogy Within and Beyond the Classroom
No full text“Critical Prison Studies in Dialogue: Teaching and Learning” is a multi- week, undergraduate project that combines critical thinking, collaboration, and an analysis of the social relations and material logics of carceral systems in the U.S. It consists of a series of carefully scaffolded activities that create space for students to imagine a world in which incarceration is not the logical answer to the political and social problems that plague us. It also asks students to theorize, experience, and reflect on the process of abolition-feminist movement building on multiple scales within and outside the classroom
