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Showing 1 to 19 of 19 for “"Design Under Uncertainty"”.
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Optimal trajectory design under uncertainty
Reference trajectory design for atmospheric reentry vehicles can be accomplished through trajectory optimization using optimal control techniques. However, this method generally focuses on nominal vehicle performance and does not include robustness considerations during trajectory design. This …
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Multidelity approaches for design under uncertainty
… to account for their effects during engineering design to achieve robust and reliable systems. One approach is to represent uncertainties as random inputs to the numerical model of the system and investigate the probabilistic behaviour of the model outputs. However, performing optimization in …
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Multifidelity methods for multidisciplinary design under uncertainty
For computational design and analysis tasks, scientists and engineers often have available many different simulation models. The output of each model has an associated uncertainty that is a result of the modeling process. This uncertainty is referred to as model discrepancy and is defined as the …
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Alternative Freight Contracts: Data-driven Design Under Uncertainty
… how firms (shippers) should incorporate market uncertainty into their strategic procurement of truckload (TL) transportation services from suppliers (carriers). These direct point-to-point TL movements are a major segment of total freight volumes for shippers. As such, firms emphasize the need …
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Bayesian Saltwater Intrusion Prediction and Remediation Design under Uncertainty
… groundwater simulation models are subjected to uncertainty in their predictions. The goals of this research are to: (1) quantify the uncertainty in the groundwater model predictions and (2) investigate the impact of the quantified uncertainty on the aquifer remediation designs. To pursue the …
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Simulation-Based Design Under Uncertainty for Compliant Microelectromechanical Systems
… led to a greater emphasis on simulation-based design for increasing first-pass design success and reliability. The use of compliant or flexible mechanisms can help eliminate friction, wear, and backlash, but compliant MEMS are sensitive to variations in material properties and geometry. This …
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Optimal parameter sampling for aquifer remediation design under uncertainty
… are rarely known with certainty. To address this uncertainty, one may conservatively design the remediation system, so that the probability of failure to restore the aquifer is small. Alternatively, one may sample the aquifer to determine parameter values so that a less conservative remediation …
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Adaptive and Responsive Design Under Uncertainty for Resource-Constrained Small Satellites
… survival and operation. Traditionally, satellite design methods mitigate the effects of uncertainty through the use of ample margin. However, robust designs often sacrifice significant nominal performance in exchange for this reduced sensitivity to uncertainty. Small satellites in particular are …
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Microgrid planning and design under uncertainty: A case study in Northern Angola
… less than 2MW and (iii) is flexible enough to undergo future expansion as needed over time. The design of a proposed Microgrid solution for N'zeto and Tomboco villages located in Angola is developed through a thorough context study used in conjunction with remotely acquired contextual data and …
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Design as a search problem : interactive visualization for system design under uncertainty
… does not exist. To make informed decisions, and design successful strategies for value sustainment, effective visualization and analysis techniques are needed to derive valuable insights from this data. These challenges motivate this thesis research. The aim of this thesis is to leverage recent …
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Addressing deep uncertainty in space system development through model-based adaptive design
… a space system, many properties of the design space are initially unknown and are discovered during the development process. Therefore, the problem exhibits deep uncertainty. Deep uncertainty refers to the condition where the full range of outcomes of a decision is not knowable. A key …
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Comparing Probabilistic and Fuzzy Set Approaches for Designing in the Presence of Uncertainty
… fuzzy set models describe different aspects of uncertainty. Probabilistic models primarily describe random variability in parameters. In engineering system safety, examples are variability in material properties, geometrical dimensions, or wind loads. In contrast, fuzzy set models of uncertainty …
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Shape optimization of lightweight structures under blast loading
… blast events has made blast mitigating component design an active research subject. Standard up-armoring of ground vehicles can significantly increase the mass of the vehicle. Without concurrent modifications to the power train, suspension, braking and steering components, the up-armored vehicles …
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Computational Design of 2D-Mechanical Metamaterials
… that display unique properties from their underlying microstructure topology rather than the constituent material they are made from. Their effective properties displayed at macroscale depend on the design of their microstructural topology. In this work, two classes of mechanical …
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Development and Use of a Spatially Accurate Polynomial Chaos Method for Aerospace Applications
Uncertainty is prevalent throughout the design, analysis, and optimization of aerospace products. When scientific computing is used to support these tasks, sources of uncertainty may include the freestream flight conditions of a vehicle, physical modeling parameters, geometric fidelity, numerical …
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Designing a sustainable water storage system for livestock in Bodaway Gap using contextual engineering principles and community engagement
… Engineering framework that integrates technical design with sociocultural, political, and environmental realities to address water scarcity in Bodaway Gap, Arizona. Although the entire project originated under the assumption that household drinking water represented the community's most urgent …
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Time-dependent reliability methodologies with saddlepoint approximation
… to predict the time-dependent reliability in the design stage, given possible catastrophic consequences of a failure. Although extensive research has been conducted on reliability analysis, estimating the reliability accurately and efficiently is still challenging. The objective of this work is to …
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Computational and Machine Learning-Reinforced Modeling and Design of Materials under Uncertainty
… of materials is fundamentally determined by the underlying microstructural features. Therefore, designing high-performance materials using multi-scale models plays a significant role to improve the predictability, reliability, proper functioning, and longevity of components for a wide range of …
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A Data Mining Methodology for Vehicle Crashworthiness Design
<p>This study develops a systematic design methodology based on data mining theory for decision-making in the development of crashworthy vehicles. The new data mining methodology allows the exploration of a large crash simulation dataset to discover the underlying relationships among vehicle crash …