Task load measuring

These values are determined by experiment. It is, however, by no means a trivial task to measure the lamina compressive and shear strengths (52,53). Also the failure of the first ply of a laminate does not necessarily coincide with the maximum load that the laminate can sustain. In many practical composite laminates first-ply failure may be accompanied by a very small reduction in the laminate stiffness. Local ply-level failures can reduce the stress-raising effects of notches and enhance fatigue performance (54). 

K. Izzetoglu, S. Bunce, M. Izzetoglu, B. Onaral, and K. Pourrezaei. fnir spectroscopy as a measure of cognitive task load. In Proceedings of the 25th Annual International Conference of the IEEE EMBS, pages 3431-3434, 2003. 

Workplace assessments usually lequiie special attention to task demands, performance, and load. The demand measures form the counterpart of the performance measures, they specify the task or demand requirements of the environment (inputs whereas the performance/outcome measures define the way the operational output is assessed. Load measures, which are often the prime focus of ambulatory studies, can only properiy be interpreted in the context of task requirements, on the one hand, and performaiKe, on the other. 

Task and stimulus conditions, load measures, task demands... 

Second, to check the workload manipulation the participants were asked to complete the NASA-Task Load Index (TLX Hart Staveland, 1988). The TLX is a subjective measure of workload composed of six rating scales that address the contributions of various sources of workload. Prinzel et al. (in press) had their participants complete the TLX after each 16-minute period. 

M. R. Wilson, J. M. Poolton, N. Malhotra, K. Ngo, E. Bright, and R. S. Masters, "Development and validation of a surgical workload measure The surgery task load index (SURG-TLX),"... 

Due to the complexities and challenges of measuring creativity, there have been different approaches for assessment (Charyton 2005, 2008 Charyton et al. 2011) and evaluation (Carroll and Latulipe 2009). Carroll and Latulipe (2009) suggest that the Creativity Support Index (CSl) may be useful and was modeled after the NASA Task Load Index (TLX). The CSl contains Likert scale questions that aim to measure Czikszentmihalyi s ow construct that focuses on being absorbed in the creative process. The CEDA could be used along with these other measures for NASA. 

The task load analysis approach calculates the requirements of target tasks as they are which may provide the psychological influence of the operators. This approach measures the workload by estimating the resources used for tasks [Mitchell, 2000a]. 

Given the predominance of the information processing approach to assessing driver behavior, it is worthwhile to briefly describe the main methods that have been developed to measure it. In general three approaches have been used to assess mental task load performance based measures using a secondary task, physiological measures of stress, and subjective evaluations of mental load. 

Determining Mental Load. To obtain a model, we first needed to determine which measures would most likely correlate with user interruptability. As a first candidate, we examined measures of user mental load during a task. In the past, the most common measure of mental load has been NASA s Task Load Index (TLX) [11], a subjective self-assessment of various mental and physical aspects of a task. Results take the form of a multi-dimensional rating, based on the weighted average of six subscales mental demand, physical demand, temporal demand, performance, effort, and frustration. 

The above problems of fabrication and performance present a challenging task of identification of the governing material mechanisms. Use of nonlinear finite element analysis enables close simulation of actual thermal and mechanical loading conditions when combined with measurable geometrical and material parameters. As we continue to investigate real phenomena, we need to incorporate non-linearities in behavior into carefully refined models in order to achieve useful descriptions of structural responses. 

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