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1. Reducing Simulation Input-Model Risk via Input Model Averaging

   https://doi.org/https://doi.org/10.1287/ijoc.2020.0994  

   Nelson, Barry L.; Wan, A.T.K.; Zou, G; Xinyu Zhang, X; Jiang, X (October 2020, INFORMS journal on computing)

   null (Ed.)

   Input uncertainty is an aspect of simulation model risk that arises when the driving input distributions are derived or “fit” to real-world, historical data. Although there has been significant progress on quantifying and hedging against input uncertainty, there has been no direct attempt to reduce it via better input modeling. The meaning of “better” depends on the context and the objective: Our context is when (a) there are one or more families of parametric distributions that are plausible choices; (b) the real-world historical data are not expected to perfectly conform to any of them; and (c) our primary goal is to obtain higher-fidelity simulation output rather than to discover the “true” distribution. In this paper, we show that frequentist model averaging can be an effective way to create input models that better represent the true, unknown input distribution, thereby reducing model risk. Input model averaging builds from standard input modeling practice, is not computationally burdensome, requires no change in how the simulation is executed nor any follow-up experiments, and is available on the Comprehensive R Archive Network (CRAN). We provide theoretical and empirical support for our approach. 

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2. Distributional input uncertainty

   https://doi.org/10.1109/WSC57314.2022.10015344  

   Chen, Motong; Liu, Zhenyuan; Lam, Henry (December 2023, Proceedings of the Winter Simulation Conference (WSC))
3. FlexType: Flexible Text Input with a Small Set of Input Gestures

   https://doi.org/10.1145/3581641.3584077  

   Gaines, Dylan; Baker, Mackenzie M; Vertanen, Keith (March 2023, Proceedings of the 28th International Conference on Intelligent User Interfaces)

   In many situations, it may be impractical or impossible to enter text by selecting precise locations on a physical or touchscreen keyboard. We present an ambiguous keyboard with four character groups that has potential applications for eyes-free text entry, as well as text entry using a single switch or a brain-computer interface.We develop a procedure for optimizing these character groupings based on a disambiguation algorithm that leverages a long-span language model. We produce both alphabetically-constrained and unconstrained character groups in an offline optimization experiment and compare them in a longitudinal user study. Our results did not show a significant difference between the constrained and unconstrained character groups after four hours of practice. As expected, participants had significantly more errors with the unconstrained groups in the first session, suggesting a higher barrier to learning the technique.We therefore recommend the alphabetically-constrained character groups, where participants were able to achieve an average entry rate of 12.0 words per minute with a 2.03% character error rate using a single hand and with no visual feedback. 

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4. Constrained Control of Input Delayed Systems With Partially Compensated Input Delays

   https://doi.org/10.1115/DSCC2020-3271  

   Abel, Imoleayo; Janković, Mrdjan; Krstić, Miroslav (October 2020, ASME 2020 Dynamic Systems and Control Conference)

   null (Ed.)

   Abstract Control Barrier Functions (CBFs) have become popular for enforcing — via barrier constraints — the safe operation of nonlinear systems within an admissible set. For systems with input delay(s) of the same length, constrained control has been achieved by combining a CBF for the delay free system with a state predictor that compensates the single input delay. Recently, this approach was extended to multi input systems with input delays of different lengths. One limitation of this extension is that barrier constraint adherence can only be guaranteed after the longest input delay has been compensated and all input channels become available for control. In this paper, we consider the problem of enforcing constraint adherence when only a subset of input delays have been compensated. In particular, we propose a new barrier constraint formulation that ensures that when possible, a subset of input channels with shorter delays will be utilized for keeping the system in the admissible set even before longer input delays have been compensated. We include a numerical example to demonstrate the effectiveness of the proposed approach. 

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5. Multi-Input SFQ Multiplexers

   https://doi.org/10.1109/TASC.2025.3538651  

   Oluwadamilare, Tejumadejesu; Friedman, Eby G (August 2025, IEEE Transactions on Applied Superconductivity)