Correlated Bayesian Model of Aircraft Encounters in the Terminal Area Given a Straight Takeoff or Landing

The incorporation of unmanned aircraft terminal operations into the scope of Detect and Avoid systems necessitates analysis of the safety performance of those systems—principally, an assessment of how well those systems prevent loss of well clear from and collision with other aircraft. This type of analysis has typically been conducted by Monte Carlo simulation with synthetic, statistically representative encounters between aircraft drawn from an appropriate encounter model. While existing encounter models include terminal airspace classes, none explicitly represents the structure expected while engaged in terminal operations, e.g., aircraft in a traffic pattern. The work described herein is an initial model of such operations, scoped at this time specifically for assessment of unmanned aircraft landings and encounters with other aircraft either landing or taking off. The model shares the Bayesian network foundation of other MIT Lincoln Laboratory encounter models but tailors those networks to address structured terminal operations, i.e., correlations between trajectories and the airfield and each other. This initial model release is intended to elicit feedback from the standards-writing community.

La projection intégrée au Sketchpad III : origine en devenir d’un terrain critique de l’infographie

Le dessin d’architecture traditionnel repose sur la technique de projection : des lignes invisibles ou abstraites traversent un plan sur lequel leurs traces deviennent la représentation d’un objet. L’infographie associe les techniques d’informatisation et de communication avec la représentation graphique et devient une source de transformation de la technique de projection. L’analyse des programmes pionniers Sketchpad et Sketchpad III développés au MIT Lincoln Laboratory en 1963 expose cette transformation du rôle de la projection. La problématique spécifique de la représentation d’objets à trois dimensions permet de cerner des choix qui ont automatisé et dissocié les vues projectives. Les conséquences de cette transformation seront mises en évidence par un recours au travail théorique de Robin Evans et par un retour aux notions fondamentales de la géométrie descriptive.

Multimodal Biomarkers to Discriminate Cognitive State

Multimodal biomarkers based on behavioral, neurophysiological, and cognitive measurements have recently increased in popularity for the detection of cognitive stress and neurologically based disorders. Such conditions significantly and adversely affect human performance and quality of life in a large fraction of the world’s population. Example modalities used in detection of these conditions include speech, facial expression, physiology, eye tracking, gait, and electroencephalography (EEG). Toward the goal of finding simple, noninvasive means to detect, predict, and monitor cognitive stress and neurological conditions, MIT Lincoln Laboratory is developing biomarkers that satisfy three criteria. First, we seek biomarkers that reflect core components of cognitive status, such as work­ing memory capacity, processing speed, attention, and arousal. Second, and as importantly, we seek biomarkers that reflect timing and coordination relations both within components of each modality and across different modalities. This is based on the hypothesis that neural coordination across different parts of the brain is essential in cognition. An example of timing and coordination within a modality is the set of finely timed and synchronized physiological components of speech production, whereas an example of coordination across modalities is the timing and synchrony that occur between speech and facial expression during speaking. Third, we seek multimodal biomarkers that contribute in a complementary fashion under various channel and background conditions. In this chapter, as an illustration of the biomarker approach, we focus on cognitive stress and the particular case of detecting different cognitive load levels. We also briefly show how similar feature-extraction principles can be applied to a neurological condition through the example of major depressive disorder (MDD). MDD is one of several neuropsychiatric disorders where multimodal biomarkers based on principles of timing and coordination are important for detection (Cummins et al., 2015; Helfer et al., 2014; Quatieri & Malyska, 2012; Trevino, Quatieri, & Malyska, 2011; Williamson, Quatieri, Helfer, Ciccarelli, & Mehta, 2014; Williamson et al., 2013, 2015; Yu, Quatieri, Williamson, & Mundt, 2014).