A principled approach to the measurement of situation awareness in commercial aviation

The issue of how to support situation awareness among crews of modern commercial aircraft is becoming especially important with the introduction of automation in the form of sophisticated flight management computers and expert systems designed to assist the crew. In this paper, cognitive theories are discussed that have relevance for the definition and measurement of situation awareness. These theories suggest that comprehension of the flow of events is an active process that is limited by the modularity of attention and memory constraints, but can be enhanced by expert knowledge and strategies. Three implications of this perspective for assessing and improving situation awareness are considered: (1) Scenario variations are proposed that tax awareness by placing demands on attention; (2) Experimental tasks and probes are described for assessing the cognitive processes that underlie situation awareness; and (3) The use of computer-based human performance models to augment the measures of situation awareness derived from performance data is explored. Finally, two potential example applications of the proposed assessment techniques are described, one concerning spatial awareness using wide field of view displays and the other emphasizing fault management in aircraft systems

Morphological Changes Accompanying the Transition from Juvenile (Atmospheric) to Adult (Tank) Forms in the Mexican Epiphyte Tillandsia Deppeana (Bromeliaceae)

This is the publisher's official version, also available at: http://www.jstor.org/stable/10.2307/2443800.Two distinct morphological forms characterize the ontogenetic development of the epiphytic bromcliad Tillandsia deppeana. Juveniles are characterized by a non-impounding rosette of small, linear leaves covered with elaborate trichomes possessing a 4 + 8 + 16 + 64 shield cell pattern. The broader transitional leaves, which form an impounding rosette prior to the initiation of true adult leaves, also possess trichomes with the 4 + 8 + 16 + 64 cell pattern. Adult individuals have large, broad leaves with overlapping, sheathing bases which impound water and debris. These leaves have trichomes with shields exhibiting a 4 + 8 + 32 cell pattern. Trichome density is fairly uniform in the juvenile leaves with trichomes covering 100% of leaf surfaces, whereas in the adult leaves density is high at the base and diminishes significantly toward the apex. Stomatal density of both juvenile and adult leaves increases from the base to the apex, although this is most pronounced in the adults. Stomata in the adults are also arranged in longitudinal series parallel and abaxial to parallel rows of mesophyll tissue. The results of this study indicate that juveniles of 7". deppeana are more similar morphologically to adult atmospheric-type tillandsioid species than to the tank-forming adults into which they eventually develop

Inventory of Property owned by William W. Adams

Inventory of property owned by William W. Adamshttps://scholarsjunction.msstate.edu/lantern-mcpc/1211/thumbnail.jp

Appraisal of Property owned by William W. Adams

Appraisal of property owned by William W. Adamshttps://scholarsjunction.msstate.edu/lantern-mcpc/1210/thumbnail.jp

Avian Use of a Bottomland Hardwood Afforestation Site in the Red River Alluvial Valley

Colby W. Sharp is a Graduate Associate in the School of Biological Sciences at Louisiana Tech University. Heidi L. Adams and William B. Patterson are Assistant Professors in the School of Biological Sciences at Louisiana Tech University

Bostonia. Volume 12

Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs