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Knowledge Management Modeling and Decision Analysis for USMEPCOM
Get PDFThis thesis explores the adoption of Value-Focused Thinking (VFT) in enhancing the Knowledge Management (KM) program at USMEPCOM, aiming to align decision-making with the organization’s values and goals. Through evaluating the current knowledge flow and policy drafts, it proposes categorizing command messages, establishing a centralized information repository, and scheduling a daily order release to improve information accessibility and operational readiness. Although no alternative offers a perfect solution, implementing Command Message Categorization is expected to significantly enhance operational efficiency and prepare USMEPCOM for future challenges
Radiological Decontamination Methodologies on Litter-Bound Patients in Arctic Environments, and the Associated Airborne Risks Posed to First Responders
Get PDFThis study was conducted to determine if air-based decontamination (decon) methods would be effective at both treating patients exposed to dry, radiological contamination as well as reducing its re-aerosolization during the disrobing process, such that these methods could be applied on litter-bound patients in extreme cold environments. A litter-bound, full-size mannequin dressed in a set of standard military issue extreme cold weather jacket and pants coated in 27 g (1 Tbs) of Copper Oxide (density 6.315 g/cm3 ) was given one of three treatments for dry aerosol decon. The three cleaning treatments included high-efficiency particulate air (HEPA) vacuum, a makeshift air shower, and a no-treatment control. Following the treatment, researchers removed the uniform off the mannequin and optical particle counters (OPCs) were used to take air samples in the immediate area of the simulated litter-bound patient to estimate airborne total dust concentrations posing risk to first responders during disrobing. Each treatment was conducted ten times for a total of 30 trials. An analysis of variance (ANOVA) test ( α=0.05 ) and Tukey Inferential test for multiple comparisons determined that HEPA vacuuming was significantly better than no treatment ( p=.0498 ) and resulted in an 86% reduction of re-aerosolized contaminant (mg/m3 ) during disrobing. Conversely, the air shower was significantly worse than no treatment (
Discerning Satellite Subsystem Costs to Improve Cost Estimation
Get PDFThe race for supremacy in the space environment is accelerating, with the United States taking a significant step by establishing its dedicated military branch for space operations. Achieving dominance in this realm relies on efficiently managing costs and securing rapid funding to initiate new programs. One step towards accomplishing this goal is to comprehend the cost distribution across the primary components of a Space Vehicle Bus and to delve into lower-level Work Breakdown Structure (WBS) elements for more precise and expeditious cost estimations. To achieve this, descriptive statistics for a variety of Bus subsystem WBS elements are provided in this study. Additionally, this research helps facilitate data selection decisions when developing Cost Estimating Relationships (CERs). Over the years, there have been transformations in satellite sizes, shapes, orbits, and mission requirements. Cost practitioners must make decisions on how to model and/or segregate data by these characteristics when developing their estimates. This research provides a flowchart for practitioners to follow when making data decisions for their CERs. It is recommended that cost practitioners initially filter by mission or orbit types. The subsequent level of separation suggests filtering based on shape, but the loss of data points may make this infeasible in some instances. Satellite size is also considered, but not recommended
Cost Estimating Relationships for Avionics Recurring Production Box Costs
Get PDFThis research investigates a dataset of 286 Department of Defense (DoD) avionics boxes, employing regression methods to establish seven cost estimation relationships (CERs) for predicting avionics recurring production box costs. Not confined to T100 costs, three baseline models use Ordinary Least Squares (OLS) T100 cost, explaining 83%, 86%, and 83% of dataset variation. Additionally, four robust models depict mean and median, T100 OLS, and T100 non-linear learning curves, explaining 67%, 65%, 97%, and 87% of the variation. These models strike a balance between simple baseline and overly complex computational models. Identified cost drivers include weight, year of first flight, volume, and the subfunctions radio and voice. This study represents the most extensive regression analysis of avionics box costs for recurrent production expenses, serving as a valuable reference for cost analysts in validating early estimations
Deploying Field-Capable Genome Sequencing: Human Performance Considerations Under Various Personal Protective Equipment Ensembles
Get PDFField-portable genome sequencing enhances the Department of Defense\u27s strategy for detecting biological threats, particularly in resource-limited environments. While current field-capable detection methods are effective, challenges in identifying emerging threats pose risks to personnel safety. As biotechnological advancements like portable nanopore genome sequencing can advance biological detection capabilities, the viability of conducting laboratory tasks under Mission-Oriented Protective Posture (MOPP) ensembles lacks sufficient data. This research assesses the effectiveness of tools like pipettes, centrifuges, vortexes, and nanopore sequencing within a MOPP ensemble. Novice participants were utilized to explore the extension of this capability, and they completed tasks in three conditions: Fatigues, Laboratory Personal Protective Equipment, and MOPP IV, following a Latin-square design order. Timing, errors, and Likert-scale questionnaires quantitatively measured participants\u27 confidence. Analysis revealed significant confidence differences in MOPP compared to Laboratory PPE and Fatigues (p=0.0078), indicating moderate confidence. No statistical errors differences were identified (p=0.5445). Task completion times varied significantly (p=0.0110), potentially increasing by 3% to 112%. This investigation provides an understanding of the imperatives for in-field laboratory operations, including portable genome sequencing. It explores potential implications within a MOPP IV ensemble, offering valuable insights into the challenges associated with employing this technology in exigent circumstances
Generalized Characterization of Biaxial Media using Ultra-Wideband Multi-Static Focused Beam System with Polarimetric Calibration
Get PDFNovel metamaterial and metasurface realizations provide unique control of the electromagnetic wave dispersion but present many challenges for accurate constitutive parameter extraction. One measurement approach commonly employed is a freespace non-destructive focus beam system. Modern implementations are configured with multi-static dual-polarized capabilities for characterizing complex materials and offer many advantages by enabling ultra-wideband sampling, multiple measurement degrees of freedom and larger sample sizes. Practical electromagnetic material characterization of complex bianisotropic media requires the advancement of wave propagation analysis and calibration schemes. This research focuses on generalized biaxial media characterization and multi-static focused beam system metrology with polarimetric calibration schemes and measurement standards. The fundamental analysis is developed to solve the forward model theory for general biaxial media based on eigenwave solutions from conventional and coordinate system transformation approaches. Theoretical scattering parameter expressions are identified for any excitation polarization and incidence angle. Then, a polarimetric self-calibration scheme for focus beam systems is developed using physically realizable metrology standards. Finally, the propagation theory and calibration schemes are validated with precision measurements and a revised measurement procedure for improved clutter subtraction. To support polarimetric calibration an ultra-wideband wire-grid polarizer measurement standard is developed based on manufacturing concepts from A-sandwich radomes. The polarimetric calibration techniques and measurement procedures are applicable to biaxial media as well as any general sample characterization
Developing a Lean Spacecraft Test and Evaluation Architecture for a Contested Space Domain
Get PDFThe US Space Force (USSF) is currently investigating possible opportunities to improve the testing paradigm of spacecraft in order to get assets on-orbit faster, while maintaining suitable quality to meet mission needs in a contested space environment. To support this goal, USSF’s approach to test and evaluation (T&E) is centered around the concept of integrated test. In this research, the space text lexicon is defined, addressing the ambiguities on exactly what integrated test is with respect to spacecraft systems development and on-orbit mission assurance. This research considered any statistical trends in categorical discrepancies (i.e., anomalies) during prelaunch integration and test (I&T) between past and present data, as well as any identified interconnected anomalies. Additionally, anomaly trends in operational on-orbit data were statistically analyzed in the same manner as pre-launch anomalies in order to identify any correlations between prelaunch tests and operational space vehicle reliability. The main correlation was that the thermal vacuum test was a predictor of the frequency of anomalies a spacecraft payload would experience while on orbit. Correlations were also made demonstrating the effects of sequential missions reduce frequency of discrepancies and increase the robustness of a spacecraft’s performance. This informed the development of a novel statistical function called the Spacecraft Survivability Index (SSI), characterizing space vehicle reliability through accounting for the assessed reliability of individual subsystems/components, together with the number and characteristics of component/system testing both performed and not performed.
These analyses will be used in the future to refine the SSI and use the SSI to model space vehicle I&T activities in order to assess how adjusting the I&T flow (through truncation, omission, etc.) affect space vehicle reliability. This research is intended to provide a quantitative means to demonstrate how the spacecraft I&T flow can be optimized for mission needs. This research will help determine impacts of practices, which will in turn be used to suggest and support Lean integrated spacecraft testing policy to the Test and Evaluation office at Headquarters USSF (USSF/TE), which reports directly to the Vice Chief of Space Operations. This is critical to the integrated test concept because it will clearly integrate the effects of pre-launch testing with on-orbit operations, enabling the collaborative planning between the contractor, Systems Program Office (SPO), testers, and operations teams, as well as a clear means to share data and independently evaluate system survivability. This work recommends the extensive use of government-held architectures to streamline flow of communication and data, as well as ensure integration between test events, including those as the NSTTC, all the while suggesting preference be made towards spacecraft that are commoditized and/or mature in design, as well as qualified in design
Statistical Reliability Estimation of Space Launch Vehicles
Get PDFSpace launch vehicle reliability is imperative to understand since launch vehicles are crucial in getting payloads into space for a hopefully successful mission. This thesis examines the reliability of commercial, civil, and military space launch vehicles through trend analysis and a variety of statistical methods. Data sets obtained from the Seradata database are analyzed for trends by looking at data subsets including launch date, launch country, final mission orbit, section (commercial, civil or military), launch vehicle family and failed subsystem. First-level Bayesian analysis and mean success rates are performed, primarily split up by launch vehicle family and total launches, and the results analyzed. Bayesian estimation techniques are the common practice in launch vehicle reliability studies currently published and provide great insight about both infant and mature space launch vehicles. Using Bayesian analysis techniques and trend analysis, many conclusions are made throughout this document related to overall launch reliability, country and sector specific launch reliability, and deep space related mission launch reliability. Trend analysis was performed on 1873 launches that occurred during the period 2000 to 2023 and it was found that while the number of launches has begun to exponentially increased over the 23-year period, the number of failures stayed within 10% of total launches each year, with the average success rate being 95% annually. 56% of launches were sent into low-Earth orbits (LEO) and 32% were sent into geosynchronous equatorial (GEO) orbits. Although both had success rates above 92%, LEO launches accounted for 73% of total launch failures while GEO launches accounted for 18% of launch failures. Specifically, looking at U.S. and Russian vehicles, the main system where failure occurred was withing the propulsion system where 72.3% of 47 reported launch failures. First-level Bayesian techniques were performed on 49 launch vehicle families and it was found that vehicles with a high accrual of launches performed better, resulting in first-level success rates of greater than 90%
Preliminary Analysis of Disposal Reachability for Selected Lagrange Points
No full textAnalytic research was conducted to determine disposal reachability about orbit families in L1, L2, and L4 Lagrange points. Candidate orbits were selected based on lower stability index in the respective orbit families about the Lagrange points. Initial considerations for the delta-v applied about the orbit families began at a magnitude corresponding to current geosynchronous orbit disposal maneuvers. This research analyzed candidate orbit families and determined groupings of low-cost delta-v transfers to determine reachability of possible maneuvers for graveyard orbits or escape trajectories
Investigating Hardware-based AES Countermeasures in the SAM4L Microcontroller for Side-channel Attack Mitigation
Get PDFSide-channel attacks (SCAs) represent a sophisticated method by which attackers exploit indirect pathways, such as power leakage and electromagnetic emissions to glean sensitive information from microprocessors. These attacks analyze variation in power consumption during operations like data encryption to infer protected data, potentially compromising the security of the device. For example, observing the power draw differences when a device encrypts known data can also serve defensive purposes. Attacks often overlook emissions and power patterns, while focusing on avoiding network and host-based detection systems. This oversight presents an opportunity for security professionals to use SCAs to enhance system defenses by monitoring these side channels for anomalies that indicate unauthorized access or operations. The dual nature of SCAs necessitates a deeper understanding and strategic implementation of countermeasures in microprocessor architecture to safeguard against vulnerabilities while potentially harnessing these channels for defensive insights