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B B Morgan

Publications and source records attributed to B B Morgan.

17 recordsLinked to original sources

Automation, task difficulty, and aircrew performance.

The effects of an automated system on team processes and performance were assessed in a laboratory simulation. Two-person crews were required to fly a complex emergency-response scenario under conditions of low and high workload. These flights were completed with or without the aid of an autopilot. The results indicated that the autopilot was effective in reducing subjective workload. However, the automation was associated with improved performance on only 1 of 4 performance measures. Furthermore, it was observed that problem-solving performance was worse in the autopilot condition during the high-workload flights. Investigation of crew process data indicated that workload savings afforded by the autopilot might have been invested in more explicit coordination. The results are discussed in terms of their implications for military aviators' performance, system design, and team training.

Adult↗

Anaphylactic transfusion reaction associated with a possible anti-A2m(1).

A 42-year-old leukaemic black male developed shortness of breath, itching, hot flushes, substernal pain, marked hypotension, and cardiorespiratory arrest after the infusion of 50 ml of pooled platelet concentrates. The patient had had one previous and uneventful red blood cell transfusion. Serologic studies of this patient's post-transfusion serum showed the presence of an antibody against one denatured IgA2 protein with the phenotype A2m(1 + 2-). All of the platelet donors were A2m(1) positive. The patient was successfully transfused with platelets from donors with the phenotype A2m(1 - 2+). Although 35.8% of Blacks and 30.0% of Chinese are A2m(1) negative, this is the first reported transfusion reaction associated solely with the occurrence of a possible anti-A2m(1) in an individual of the type A2m(1 - 2+).

Adult↗

Information processing in a binary classification task.

Three choice-reaction time studies were conducted to investigate whether information processing is exhaustive or self-terminating, serial or parallel, and N-dependent or N-independent. A total of 54 subjects were required to make key-pressing responses to one, two, or three digits presented in a circular display; one key was pressed if the display contained one or more target digits and another key was pressed if the display contained only nontarget digits. The first two studies utilized within-subjects designs in which the displays were constructed from only one target and one nontarget item (Study 1) or from three target and seven nontarget items (Study 2). The third study used a between-subjects design in which different groups of subjects responded to one-, two-, or three-element displays. In general, the results indicate that CRTs increased as the total number of display elements increased and decreased as the number of target elements (or the ratio of target to nontarget items) increased for a given display size. When only target elements were presented, CRT was independent of the number of elements displayed, and when only one target was presented, CRT increased as total number of elements increased. Theses combined results are interpreted as support for the inference that information processing in visual search tasks tends to be self-terminating, serial, and N-dependent (of limited capacity).

Adult↗

Assessment of learning abilities using complex experimental learning tasks.

Efforts are underway to develop a computerized methodology for the reliable, valid measurement of learning abilities. Central to these research efforts are the development of Complex Experimental Learning Tasks (CELTs) that provide real-time samples of learning. Objectives of current studies are the determination of relationships between performance on CELTs and performance on traditional cognitive abilities tests and the exploration of predictive value of measures of learning ability for academic performance. After construct and predictive validity are established, this methodology may be applicable to a wide range of assessment situations, including testing for the effects of environmental toxicants on learning abilities.

Aptitude Tests↗