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Performance-Based Contracts: Discovering the Role of PBC in Resilience
Get PDFThe lifecycle sustainment costs for complex and expensive systems (e.g., aircraft, ships, or manufacturing equipment) often exceed their purchase costs. Reducing sustainment costs, even by a fraction, can create competitive advantages for the system owner. The operations and supply chain management (O&SCM) field asserts that this competitive advantage in life cycle sustainment operations is achievable through performance-based contracts. However, empirical validation of this assertion is required. This research investigates performance-based contracts to validate their asserted impact on sustainment operations and develops a branch of research to understand their role in organizational and supply chain resilience. This research consists of three independent studies, each with its own focus and objective
Simulating MQ-9 Aircrew Training to Determine Throughput, Identify Bottlenecks, and Optimize Manning Levels
No full textUnprecedented demand for unmanned aerial systems (UAS) by the United States Air Force is driving a corresponding demand on training units responsible for producing UAS aircrew. This research develops a simulation model of daily training operations based on historical data from a UAS flying training unit. Current requirements, operations, and instructor manning levels are used to derive a baseline throughput of trained aircrew. Subsequent analyses explore the impact of course frequency, class size, and instructor manning levels on trained aircrew produced. This research shows specific adjustments in staff skill mix and class size can significantly increase student throughput and reduce training time. Results drive novel approaches for course execution, increasing instructor utilization and informing staffing for appropriate manning levels required to meet growing UAS aircrew requirements
Vacuum Lift Apparatus
Get PDFAn apparatus for lifting a load to a desired altitude using an evacuated hollow lift body is disclosed. Once evacuated, the apparatus is lighter than the surrounding atmosphere. The lift body can be formed as a hollow fluid tight structure with a tube wound and sealed in a helical pattern or a dual membrane structure with a pressurized intermediate volume sandwiched between inner and outer membranes. A load can be attached to the apparatus and lifted to an altitude where the effective density of the apparatus and load is equivalent to the density of the surrounding atmosphere
How Individuals’ Opinions Influence Society’s Resistance to Epidemics: an Agent-based Model Approach
Get PDFBackground: Protecting public health from infectious diseases often relies on the cooperation of citizens, especially when self-care interventions are the only viable tools for disease mitigation. Accordingly, social aspects related to public opinion have been studied in the context of the recent COVID-19 pandemic. However, a comprehensive understanding of the effects of opinion-related factors on disease spread still requires further exploration. Methods: We propose an agent-based simulation framework incorporating opinion dynamics within an epidemic model based on the assumption that mass media channels play a leading role in opinion dynamics. The model simulates how opinions about preventive interventions change over time and how these changes affect the cumulative number of cases. We calibrated our simulation model using YouGov survey data and WHO COVID-19 new cases data from 15 different countries. Based on the calibrated models, we examine how different opinion-related factors change the consequences of the epidemic. We track the number of total new infections for analysis. Results: Our results reveal that the initial level of public opinion on preventive interventions has the greatest impact on the cumulative number of cases. Its normalized permutation importance varies between 69.67% and 96.65% in 15 models. The patterns shown in the partial dependence plots indicate that other factors, such as the usage of the pro-intervention channel and the response time of media channels, can also bring about substantial changes in disease dynamics, but only within specific ranges of the dominant factor. Conclusions: Our results reveal the importance of public opinion on intervention during the early stage of the pandemic in protecting public health. The findings suggest that persuading the public to take actions they may be hesitant about in the early stages of epidemics is very costly because taking early action is critical for mitigating infectious diseases. Other opinion-related factors can also lead to significant changes in epidemics, depending on the average level of public opinion in the initial stage. These findings underscore the importance of media channels and authorities in delivering accurate information and persuading community members to cooperate with public health policies
Applying Machine‐Learning Methods to Laser Acceleration of Protons: Lessons Learned From Synthetic Data
No full textIn this study, we consider three different machine‐learning methods—a three‐hidden‐layer neural network, support vector regression, and Gaussian process regression—and compare how well they can learn from a synthetic data set for proton acceleration in the Target Normal Sheath Acceleration regime. The synthetic data set was generated from a previously published theoretical model by Fuchs et al. 2005 that we modified. Once trained, these machine‐learning methods can assist with efforts to maximize the peak proton energy, or with the more general problem of configuring the laser system to produce a proton energy spectrum with desired characteristics. In our study, we focus on both the accuracy of the machine‐learning methods and the performance on one GPU including memory consumption. Although it is arguably the least sophisticated machine‐learning model we considered, support vector regression performed very well in our tests
A Survey of Learning Technology Integration in Information Warfare Education
No full textInformation and communication technologies (ICTs) are enduringly important in today’s world. From paying for morning coffee at the local cafe to receiving a text message from a loved one, ICTs are a part of everyday life. On a larger scale, entire nations are dependent on ICTs. From power grids to the storage of classified documents, nations have come to rely on ICTs. This dependence on ICTs has increased information warfare’s importance as a warfighting domain. In order to effectively conduct information warfare operations, operators must first be properly trained on how to be successful in this domain. The use of learning technologies could be useful to train information warfare forces. This paper surveys the current state of learning technology integration into information warfare education. Learning technologies have become commonplace in today’s professional world. Many topics in organizations are taught through learning technologies such as interactive computer-based trainings, educational videos, and more complex serious games. This is no different for information warfare professionals. Learning technologies can provide alternative ways to teach important information warfare concepts such as the roles, assets, and capabilities that are necessary to succeed in this domain. The use of artificial intelligence, game-based learning, gamification, and simulation-based learning to enhance the training of information warfare forces is discussed in this survey. Additionally, the effect of adding learning technology into information warfare education curriculum as well as the key elements for each type of learning technology integrated are analysed. This paper also identifies areas of future research to further develop this topic. These findings are useful to information warfare educators who are developing curriculum or looking for ways to introduce new technologies into existing curriculum. Artificial intelligence, game-based learning, gamification, and simulation-based learning are all great options to support information warfare education, and there are even more options that have yet to be researched that present further opportunities to study in this area. © 2024 Curran Associates Inc.. All rights reserved
Article Comprising Bonded Substrate Comprising Nanocrystals and Method of Making and Using Same
No full textThe present invention relates to devices for measuring property changes via in-situ micro-viscometry and methods of using same. The aforementioned device is inexpensive and can be used to quickly and accurately measure numerous physical and chemical property changes, including but not limited to the rate of chemical cure, change in tack, and rate of mass loss, for example, rate of moisture, solvent and/or plasticizer change
Steady Boussinesq Convection: Parametric Analyticity and Computation
No full textSteady solutions to the Navier-Stokes equations with internal temperature forcing are considered. The equations are solved in two dimensions using the Boussinesq approximation to couple temperature density fluctuations. A perturbative Stokes expansion is used to prove that that steady flow variables are parametrically analytic in size of the forcing. The Stokes expansion is complemented with analytic continuations, via functional Padé approximation. The zeros of the denominator polynomials in the Padé approximants are observed to agree with a numerical prediction for the location of singularities of the steady flow solutions. The Padé representations not only prove to be good approximations to the true flow solutions for moderate intensity forcing, but are also used to initialize a Newton solver to compute large amplitude solutions. The composite procedure is used to compute steady flow solutions with forcing several orders of magnitude larger than the fixed-point method developed in previous work
A Panel Data Regression Model for Defense Merger and Acquisition Activity
Get PDFExcerpt: This paper examines the relationship between a prime contractor\u27s financial health and its mergers and acquisitions (M&A) spending in the defense industry. It aims to provide models that give the United States Department of Defense (DoD) indications of future M&A activity, informing decision-makers and contributing to ensuring competitive markets that benefit the consumer.
The results show a significant relationship between efficiency and M&A spending, indicating that companies with lower efficiency tend to spend more on M&As. However, there was no significant relationship between M&A spending and a company\u27s profitability or solvency. These results were consistent with previous research and the study\u27s hypotheses for profitability and solvency. However, the effect of liquidity was the opposite of the expected result, possibly due to the defense industry\u27s different view on liquidity compared to previous research
Charactering Receiver Clocks for the Detection and Identification of Inauthentic GNSS Signals
No full textGNSS receiver clock drift can be estimated as part of the Time Differenced Carrier Phase solution. In this work, a commercial receiver driven by a few configurations of clock is used to estimate the clock drift from multi-constellation GNSS data. Since inauthentic GNSS signals generated with a simulator have an impact on the receiver clock solution, the simulator may be detected or even identified by observing changes in the receiver clock drift solution