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The Current Status of the Startup CubeSat Program in TASA
Get PDFThe Startup CubeSat Program, approved by the National Science and Technology Council in Taiwan, spans from 2022 to 2031, covering a total duration of ten years. Serving as an incubator for Space Startups in Taiwan, the program is designed to assist vendors in completing proof-of-concepts (POCs) for their CubeSat missions, ensuring the viability and sustainability of their business models in the future. The initial phase of the Startup CubeSat Program comprises a 3U communication CubeSat and a 3U remote sensing CubeSat. The 3U Communication CubeSat aims to showcase the capabilities of high-speed satellite loT applications. Meanwhile, the 3U remote sensing CubeSat will focus on observing the concentration of chlorophyll on the ocean surface to support pelagic fisheries. Both CubeSats are currently in the integration and testing stage, with a scheduled launch date in July 2024. The second phase of the Startup CubeSat Program comprises three projects: a Ka-band communication mission, a Ku/L-band loT mission, and an ocean color imaging mission. In each project, there are four 8U CubeSats to enhance satellite services, facilitating global coverage and improved revisit times. All the details of these projects will be thoroughly described in this paper
Using Star Trackers to Improve Space Situational Awareness
Get PDFThe Kessler syndrome presents a scenario in which space debris produced from an orbital collision increases the risk of further collisions, resulting in an exponential growth of on-orbit debris. With the proliferation of Resident Space Objects (RSOs) in the near-Earth space environment, continual development of ground-based and space-based detection, monitoring, and cataloguing systems is paramount in mitigating the risks associated with collisions. Currently, cataloguing RSOs primarily utilizes ground-based optical and radar systems, however, their performance is impacted and constrained by weather and atmospheric distortions.
As a result of the challenges and limitations of ground-based observations, there is increasing demand for space-based RSO detection and monitoring by means of dedicated satellites and constellations, however, this approach requires significant upfront investment to realize. An alternative approach is the opportunistic use of star trackers, which are already used for attitude determination onboard many satellites. Collectively, by leveraging the naturally expanding and replenishing population of pre-existing flight hardware, these sensors can be used as an extensive network to collect on-orbit Space Situational Awareness (SSA) data without any significant investment. This approach mitigates the constraints of traditional ground-based RSO detection systems while also reducing the cost inherent in deploying a dedicated space-based system.
An RSO within the Field of View (FOV) of a star tracker can be detected and characterized through the application of computer vision and astronomy algorithms applied both within the on-board software and through the analysis of the downlinked data. An algorithm is developed for on-board RSO detection, allowing for the necessary characterization data to be compiled and downlinked for further analysis. The proposed detection algorithm utilizes a single-frame detection approach, in which the geometry and orientation of the observed signals are analyzed to differentiate the RSOs from the background stars. Combined with knowledge of the observer’s position and velocity, sequential detections of individual RSOs provides insight into their Keplerian orbital elements. To validate the effectiveness of the proposed algorithms, a series of synthetic and real night sky images are captured, and the algorithm is utilized to detect the observed RSOs
Qualification of 3D-Printed Titanium Volume-Optimized Propulsion Tanks for Small Satellites
Get PDFThe current state of the art for small satellite chemical propellant tanks is limited in design customization, is expensive, and is volumetrically inefficient within the cuboid volumes of small satellite buses. Space Dynamics Laboratory and Velo3D Inc. partnered to develop propulsion tank technology that solves these challenges using metal additive manufacturing (AM). We designed, analyzed, built, heat-treated, post-machined, precision cleaned, and qualification tested a titanium 6A14V volume-optimized 3D-printed propulsion tank with an integral printed propellant management device (PMD). They are rated for a maximum expected operating pressure of 400 psi. These tanks are 3D-printed in the desired cuboid mission geometries with significantly faster lead times, yielding a much lower cost while improving delta-V per size envelope.
This project focused on half ESPA satellite sized tanks, compatible with hydrazine or green propellant, with a scalable methodology to execute any size from 1U to full ESPA. The qualification testing results, processes developed, lessons learned, and key takeaways for the industry are presented. Additionally, this paper outlines a roadmap for the industry showing the pre- and post-printing processing steps needed for success in metal AM for propulsion tanks, referencing the applicable industry standards. We performed a thorough specimen testing campaign and share the results. Finally, we also designed, analyzed, 3D-printed, and heat treated a full ESPA sized propulsion tank with integral printed PMD.
This work demonstrates the viability of metal volume-optimized AM tanks for small satellite propulsion and the processes required to be successful in future projects
Balancing the Scales: Evaluating Variables of Greatest Impact to Profit Margins When Finishing Cattle
Get PDFThis study examines the risk associated with finishing cattle in a feedlot, specifically in the context of historically high cattle prices and quality grade grid marketing systems that have not adjusted to these elevated prices. The analysis also looks at performance factors that drive profitability differences in pens of cattle in a commercial feedlot, and how market factors also impact profitability. Regression analysis determines the significance of performance variables such as days on feed, average daily gain, feed conversion rates, and carcass characteristics on pen profitability. The impact of cattle breeding and pre-feedlot management of the cattle are also considered in the analysis. The outcomes of this research provide essential insights for stakeholders aiming to optimize economic gains in the contemporary cattle feeding industry
Evaluating the Cost of Gain and Financial Returns of Cattle Fed Hydroponically Produced Barley Fodder
Get PDFHydroponically produced fodder continues to garner attention as a feed source within livestock production. This attention in part is due to a belief that hydroponically produced fodder is more efficient in its use of inputs such as water when compared to conventional feeds. Water efficiency is especially appealing in areas like the Intermountain West region of the U.S where water availability is often constrained. This analysis looks to understand how using hydroponically produced barley fodder to finish steers compares economically to finishing steers on a nutritionally equivalent conventional finishing ration. To do so, a stochastic simulation model is constructed to compare the expected cost of gain and net return per head when finishing steers on a conventional ration and hydroponically produced barley fodder ration. The simulation results suggest that finishing steers on a hydroponically produced barley fodder ration leads to a mean cost of gain 88 lower than the conventional mean net return per head. Using a sensitivity analysis to better understand these results, we find that using hydroponically produced barley fodder to finish steers becomes more financially feasible than conventionally finished steers only when conventional feed prices are pushed to unrealistic extremes
MD Simulations of Collision Effects for a Strongly Coupled Plasma
Get PDFStudying strongly coupled plasmas can be effectively accomplished using molecular dynamics (MD) simulations. We have developed an advanced MD simulation code that can analyze plasmas with various coupling parameters. This code employs a spherically symmetric cut-off Coulomb force verified through convergence tests by modulating the cut-off and minimum force ranges. Additionally, it incorporates a new algorithm for optimizing the initial positions of particles at a given temperature. This method maintains the temperature constant and the velocity distribution unchanged. As a result, we eliminate the unphysical initial rises and oscillations in temperature that a random distribution of positions causes. The code also utilizes the Monte Carlo method to achieve the desired velocity distribution with a given initial moments. The computational efficiency of the MD simulations is significantly enhanced by using graphics processing units (GPUs) for parallel computing. By employing these advanced initialization methods for particle positions and velocities, we can measure the relaxation times of various non-Maxwellian moments across different coupling parameters. The collision coefficients obtained from these measurements are then compared with theoretical values. Furthermore, the code investigates the oscillations of higher-order moments in a magnetized plasma. By applying an appropriate linear combination of moment components, we can extract eigenmodes with single frequencies from these oscillations. This work provides a cornerstone for studying strongly coupled plasmas by presenting a intuitive method for constructing the fundamental characteristic of collisions in a many-body system, the collision matrices
Improving the Long-Term Maintenance and Durability of Pervious Concrete Pavements
Get PDFImpervious concrete is constructed for most new infrastructure such as housing developments, commercial projects, and industrial facilities, which prevents stormwater runoff from infiltrating into groundwater storage. Pervious concrete is a sustainable, economical, and safe alternative to collect runoff and prevent the issues resulting from increased land development.
Although pervious concrete has the benefit of a large porous structure for water infiltration, this high porosity leads to issues with debris, sand, and other materials clogging the porous areas. Pervious concrete also has the challenge of non-standardized material preparation techniques, testing, and construction practices. As such, more research is needed to improve the strength, durability, and long-term maintenance of the concrete before pervious concrete can be used in wider applications.
This thesis seeks to utilize advanced concrete mix designs and innovative maintenance strategies to improve the long-term maintenance and durability of pervious concrete structures. To address the first objective of this thesis, two pervious concrete mix designs are developed using normal cement as a control mix and a rapid-set cement mix as an advanced alternative construction material. The viability of the rapid-set cement mix is analyzed by implementing compressive strength and freeze-thaw durability tests for both mix designs.
The second objective of the thesis is to determine the most effective maintenance method to remove debris and maintain the porous structure of three pervious concrete systems. The maintenance methods used in this thesis compare an innovative upward flush system with vacuuming method to the typical pressure washing and vacuuming method.
The results of the compressive strength and freeze-thaw durability testing show that using rapid-set cement as an advanced construction material would be a suitable replacement in pervious concrete pavements. The maintenance method testing results demonstrate the effectiveness of the innovative upward flush system as being the most efficient at removing sand from the pervious concrete model.
With the conclusions from this study, further research can be carried out to find other innovative, eco-friendly, and cost-effective ways to implement and improve pervious concrete developments
Anomaly Detection on Wind Turbine Blades Using Aerial Imaging, Image Processing, And Deep Learning
Get PDFIn reaction to rising global temperatures and carbon dioxide emissions, many countries are looking to use energy sources other than fossil fuels. One such source of energy is wind energy, which can be harvested by wind turbines. By rotating at high speeds, the blades of these large turbines are able to convert wind energy to kinetic energy, which is then converted to electricity usable by the power grid. Traditional methods for inspecting these turbines for damages are expensive, unsafe, and susceptible to human error. These turbines are so tall and so large that inspectors run the risk of falling from large heights or being injured by falling turbine debris. It is also difficult to spot every damaged area on a blade so large. A solution to this problem is to have a drone fly up and take pictures of the blades. Afterwards, these pictures can be processed by a machine learning architecture, which is a specific type of AI (artificial intelligence). The AI will then tell the inspectors if damages exist on the blades. Wind turbines are normally turned off during inspection for the safety of the inspectors. If the turbines are left on during the inspection process to save money, the blades will likely be moving, so images of the blades may be blurry. This will make it more difficult for the AI to detect damages. This is why deblurring the images before further processing could be a great way to still have accurate results from the AI with rotating blades. In this study, the health of wind turbine blades is determined using specific machine architectures along with image deblurring techniques and a custom-made image set of wind turbine blades taken with a drone
Exploring Peer-Assisted Learning in a High-School-Based Suicide Prevention Intervention
Get PDFThis dissertation evaluated a form of teaching called peer-assisted learning in which people of similar ages and knowledge teach each other a subject. In this dissertation, peer-assisted teaching occurred in a suicide prevention organization called Hope Squad, which operates as individual chapters in high schools. The author first shared details from other researchers\u27 studies on peer-assisted learning, then conducted two studies on this form of instruction in Hope Squad: The first study reported on the experiences peers have from learning from their peers, and the second study reported on peers\u27 experiences teaching their peers. This dissertation may give researchers further insight into the experiences of peer-assisted learning participants. Reported results from this dissertation\u27s studies could also help to guide Hope Squad and other comparable organizations in the resources and support they might provide to their peer-assisted learning participants
Defining Engineering Leadership and Engineering Leadership Skills From the Perspectives of ABET Leaders and Professional Engineers
Get PDFLeadership within the engineering domain has gained significant recognition in recent years due to calls from the literature, industry, and engineering professional bodies to incorporate leadership training into the engineering curriculum. In response to these calls and despite various approaches that have been implemented by engineering institutions to teach engineering leadership, research indicates that there remains a lack of consensus on the definition of engineering leadership and the specific skills that should be emphasized in the teaching of engineering leadership. Also, there is evidence in the literature that there exists a debate regarding the nature of engineering leadership, with some contending that it is indistinguishable from leadership in general, and others asserting that it incorporates engineering design principles. This lack of consensus indicates varying interpretations and priorities among engineering leadership educators, and this could impede the formation of a cohesive understanding of engineering leadership and impact the quality of leadership education in engineering programs. This study contributes to ongoing efforts by researchers to embark on empirical studies on engineering leadership to bridge the conceptual gap and arrive at a generally accepted definition. In addition, this research aims to understand the nature of engineering leadership and to highlight the leadership skills that should be emphasized in engineering leadership training. Six ABET leaders and seven engineering leaders from the industry participated in this study. Their perspectives on engineering leadership definition and the skills that should be emphasized in engineering leadership training were explored through in-depth interviews. The outcome of analyzing their data resulted in a proposed definition of engineering leadership and the identification of eighteen engineering leadership skills that should be emphasized in engineering leadership training. Also, other outcomes from the study include 1) the indication that the main difference between engineering leadership and general leadership is the technical expertise component, resulting in a dichotomous view of engineering leadership as consisting of technical expertise and interpersonal skills, 2) the indication that engineering is a leadership profession starting from self-leadership and progressing to managerial leadership based on the 3- stages of engineering leadership model, and 3) a proposed a taxonomy of engineering leadership skills as consisting of technical skills, interpersonal skills, and personal professional skills