Engineering data compendium. Human perception and performance. User's guide

The concept underlying the Engineering Data Compendium was the product of a research and development program (Integrated Perceptual Information for Designers project) aimed at facilitating the application of basic research findings in human performance to the design and military crew systems. The principal objective was to develop a workable strategy for: (1) identifying and distilling information of potential value to system design from the existing research literature, and (2) presenting this technical information in a way that would aid its accessibility, interpretability, and applicability by systems designers. The present four volumes of the Engineering Data Compendium represent the first implementation of this strategy. This is the first volume, the User's Guide, containing a description of the program and instructions for its use

Operant conditioning of monosynaptic spinal reflexes and its computational modeling and simulation

Spasticity, or more specifically hyperreflexia, is a common impairment following neurological injury such as stroke. Current clinical interventions aimed at reducing rectus femoris (RF) hyperreflexia have shown modest effect but entails side effects and limited clinical evidence. My previous research has shown that RF hyperreflexia is associated with reduced knee flexion in people post-stroke with Stiff-Knee gait (SKG). I posit that reducing RF hyperreflexia should improve walking following SKG after stroke. I developed a non-pharmacological procedure using operant H-reflex conditioning of the RF, which allows the patient to self-modulate one’s spinal reflex activity, elicited via electrical stimulation on peripheral nerve. With current evidence that operant H-reflex conditioning enhances gait function in individuals with SCI, I conducted a proof-of-concept study to examine the feasibility of this procedure on the RF for healthy and post-stroke individuals. Operant conditioning of neural activation has a high incidence of non-responders, and delineating the explicit response to feedback can help determine why some individuals may not respond to neurofeedback training. I developed a simulated operant H-reflex conditioning neurofeedback environment that separated the ability to self-regulate the neurofeedback signal from its perception by using an explicit, unskilled visuomotor task. Main outcomes indicated that biological variability modulates performance and operant strategy depending on the feedback type. While previous results provided a holistic view of the effect of feedback parameters on overall performance and operant strategy, the next approach focused on determining whether such decisions could be predicted based on feedback on a trial-by-trial basis. I observed that the feedback sensitivity was modulated by biological variability and reward threshold. I used computational models to investigate the best estimate of learning resulting in feedback-weighted averages of previous decisions. This thesis introduces a novel simulated operant H-reflex conditioning environment that serves as a simple and robust model to quickly examine learning mechanisms, optimize learning, and potentially identify non-responders.Mechanical Engineerin

Southwest Research Institute assistance to NASA in biomedical areas of the technology utilization program

The activities are reported of the NASA Biomedical Applications Team at Southwest Research Institute between 25 August, 1972 and 15 November, 1973. The program background and methodology are discussed along with the technology applications, and biomedical community impacts

Software architectural support for tangible user interfaces in distributed, heterogeneous computing environments

This research focuses on tools that support the development of tangible interaction-based applications for distributed computing environments. Applications built with these tools are capable of utilizing heterogeneous resources for tangible interaction and can be reconfigured for different contexts with minimal code changes. Current trends in computing, especially in areas such as computational science, scientific visualization and computer supported collaborative work, foreshadow increasing complexity, distribution and remoteness of computation and data. These trends imply that tangible interface developers must address concerns of both tangible interaction design and networked distributed computing. In this dissertation, we present a software architecture that supports separation of these concerns. Additionally, a tangibles-based software development toolkit based on this architecture is presented that enables the logic of elements within a tangible user interface to be mapped to configurations that vary in the number, type and location of resources within a given tangibles-based system

Transportation noise pollution - Control and abatement

Control and abatement of transportation noise pollutio

Engineering data compendium. Human perception and performance, volume 3

The concept underlying the Engineering Data Compendium was the product of a research and development program (Integrated Perceptual Information for Designers project) aimed at facilitating the application of basic research findings in human performance to the design of military crew systems. The principal objective was to develop a workable strategy for: (1) identifying and distilling information of potential value to system design from existing research literature, and (2) presenting this technical information in a way that would aid its accessibility, interpretability, and applicability by system designers. The present four volumes of the Engineering Data Compendium represent the first implementation of this strategy. This is Volume 3, containing sections on Human Language Processing, Operator Motion Control, Effects of Environmental Stressors, Display Interfaces, and Control Interfaces (Real/Virtual)

Fractal Physiology and the Fractional Calculus: A Perspective

This paper presents a restricted overview of Fractal Physiology focusing on the complexity of the human body and the characterization of that complexity through fractal measures and their dynamics, with fractal dynamics being described by the fractional calculus. Not only are anatomical structures (Grizzi and Chiriva-Internati, 2005), such as the convoluted surface of the brain, the lining of the bowel, neural networks and placenta, fractal, but the output of dynamical physiologic networks are fractal as well (Bassingthwaighte et al., 1994). The time series for the inter-beat intervals of the heart, inter-breath intervals and inter-stride intervals have all been shown to be fractal and/or multifractal statistical phenomena. Consequently, the fractal dimension turns out to be a significantly better indicator of organismic functions in health and disease than the traditional average measures, such as heart rate, breathing rate, and stride rate. The observation that human physiology is primarily fractal was first made in the 1980s, based on the analysis of a limited number of datasets. We review some of these phenomena herein by applying an allometric aggregation approach to the processing of physiologic time series. This straight forward method establishes the scaling behavior of complex physiologic networks and some dynamic models capable of generating such scaling are reviewed. These models include simple and fractional random walks, which describe how the scaling of correlation functions and probability densities are related to time series data. Subsequently, it is suggested that a proper methodology for describing the dynamics of fractal time series may well be the fractional calculus, either through the fractional Langevin equation or the fractional diffusion equation. A fractional operator (derivative or integral) acting on a fractal function, yields another fractal function, allowing us to construct a fractional Langevin equation to describe the evolution of a fractal statistical process. Control of physiologic complexity is one of the goals of medicine, in particular, understanding and controlling physiological networks in order to ensure their proper operation. We emphasize the difference between homeostatic and allometric control mechanisms. Homeostatic control has a negative feedback character, which is both local and rapid. Allometric control, on the other hand, is a relatively new concept that takes into account long-time memory, correlations that are inverse power law in time, as well as long-range interactions in complex phenomena as manifest by inverse power-law distributions in the network variable. We hypothesize that allometric control maintains the fractal character of erratic physiologic time series to enhance the robustness of physiological networks. Moreover, allometric control can often be described using the fractional calculus to capture the dynamics of complex physiologic networks

Artificial Intelligence Applications for Drones Navigation in GPS-denied or degraded Environments

L'abstract è presente nell'allegato / the abstract is in the attachmen

Low Heart Rate and Crime: Exploring the Link From an Analytical Perspective

Although low resting heart rate is often cited as “the best-replicated biological correlate” of antisocial behaviour, this association remains unexplained. Several theoretical explanations have been proposed throughout the years, but they have been mostly based on unfounded and questionable assumptions. Amongst these, fearlessness and stimulation-seeking hypotheses have gained ground and become well established in the literature, despite the fact that they have been subjected to scarce empirical verifications yielding mixed results. Therefore, employing situational action theory as a theoretical framework, a new explanatory model of the relationship between low heart rate and crime was developed. It was argued that heart rate cannot be a cause of crime, but only a marker of a cause of crime. Specifically, it was hypothesised that a person’s crime propensity would fully mediate the link between heart rate and crime. In order to test the crime propensity model and compare its efficiency against the fearlessness and stimulation-seeking hypotheses, the Cambridge adolescent behaviour study was conducted. It set out to explore the mechanism underlying the heart rate-crime association in a sample of 487 adolescents recruited from 14 schools in England. Participants completed self-report measures of stimulation-seeking, fearlessness, crime propensity, and criminal behaviour, and their heart rate was measured at rest and in response to a stressor. Crime involvement was significantly associated only with heart rate reactivity, whereas the link with resting heart rate was non-significant. Out of the three models with fearlessness, stimulation-seeking, and crime propensity as potential mediators, only crime propensity fully mediated the link between heart rate reactivity and crime, rendering the direct effect of heart rate reactivity on crime non-significant. Therefore, the empirical results supported the newly developed crime propensity model and highlighted the benefits of replacing the prevalent risk factor approach in (biosocial) criminology with an analytical approach that aims to explain what causes crime and how, and, equally importantly, what cannot cause crime.Cambridge Trust (Cambridge International Scholarship