Visual scanning

Workers in the chloralkaH industry were formerly occupationally exposed to mercury vapour. An increased frequency of intention tremors (time weighted average (TWA) of 0.026 mg/m ) was found in workers who inhaled mercury vapour for an average of 26 years. Neurobehavioural effects (motor speed, visual scanning, co-ordination and concentration) were affected in individuals with a TWA of 0.014 mg/m while workers exposed to an average of... 

The MCDF, ICSD and CSD currently acquire the vast bulk of their input data by visual scanning of the literature, followed by manual keyboarding of the relevant information. Only the PDB is compiled in its entirety from data submitted in machine readable form. Whilst all four databases perform extensive checks of data integrity, both computerized and visual, to ensure the accuracy of their final products, this function is particularly important for data acquired by manual methods. Statistics from the CSD show that some IS Tb of published structural papers contain at least one numerical error, and this is, of course, compounded by the inevitable additional risk of error due to the manual keyboarding. 

This test is from the WAIS-R digit symbol. It requires the subject to fill in blank spaces with symbols under the numbers 1 to 9. The key of numbers and symbols is in full view. After instruction and a brief practice session, the time allotment is 90 s and the score is the maximum correct in this time period. The task involves several functions visual memory, learning of nonverbal associates, sustained attention, speed of visual scanning, and visual motor planning... 

Senders, J. W. (1955). Man s capacity to use information fiom complex displays. In H. Quastler(Ed.),/w/b/7 aftow theory in psychology. Glencoe, IL Free Press. Senders, J. W. (1983). Visual scanning processes. Tilbuig, Netheriands University of Tilbuig Press. 

The aim of the research presented here is to try to use visual, scanning electron micrographs, and histological preparations as tools to predict the relative sensitivity of various plant species to simulated acid rain. It is hoped that these results might enable a prediction of the relative sensitivities of major plant groups of economic and aesthetic interest to air pollutants. 

With an energy spectrometer, the detection test is frequently based on a visual inspection of the spectrum. In this mode the analyst visually scans the spectrum and quickly establishes a background estimate based on a mental averaging of a large number of background channels. A small perturbation above this level that also has the shape of a peak is easily recognizable. Visual inspection yields a detection limit closely approaching the definition in Eqs. (11.36) and (11.37). 

Heightened awareness — A defensive driver knows what is going on in front, behind, and to the sides of the vehicle at all times. Remind your drivers to get into the habit of doing a constant visual scan aroimd the truck. This will include cleaning and properly adjusting mirrors. 

Of course, you can only use a fire extinguisher if you know where it is located. Fire code requires that portable extinguishers be located in conspicuous locations, along normal paths of travel and no more than 5 feet above the floor. Most labs will have fire extinguishers inside the lab. In labs that have Class B hazards (i.e., contain flammable liquids) the fire extinguisher must be no more than 50 feet from the door in a hallway. You should always visually scan any lab that you work in to see the location(s) of the fire extinguisher(s) and then also determine what type they are. 

Slah and spin in procedure tum(l) Skill error Failed to priorihze attention Break down in visual scan Adverse mental states Channelized attenhon... 

Bellenkes, A.H., Wickens, C.D. and Kramer, A.F. (1997), Visual Scanning and Pilot Expertise The Role of Attentional Flexibility and Mental Model Development Aviation Space and Environmental Medicine, 68, 569-579. 

Wickens, C., Dixon, S., Goh, J., Hammer, B. Pilot Dependence on Imperfect Diagnostic Automation in Simulated UAV Flights An Attentional Visual Scanning Analysis. In Proceedings of thel3th International Symposium on Aviation Psychology (2005)... 

Visual scan (speed and efficiency of movement of fixations in the visual field). Slowing of visual scan Difficulty to take in complex traffic situations Maltz and Shinar (1999) Pradhan et al. (2003). 

According to Snyder and Knoblauch (1971) to avoid a collision, pedestrians and drivers have to be aware of each other and to communicate with each other - at least partially. This interaction between the approaching driver and the crossing pedestrian requires both of them to perform at least six sequential processes (1) select the path of movement (2) visually scan the relevant scene for the potential or actual presence of the other (3) detect the other and assess his or her relative location (4) evaluate the intention of the other (5) decide on the proper course of action and (5) make the proper response to avoid a collision. If either the driver or the pedestrian performs all of these processes appropriately, a collision between them is avoided. However, if both fail to adequately perform any one of these processes then they are likely to collide. While it is a routine matter for drivers to visually search their environment for other traffic and potential obstacles (see Chapter 4), this is not the case for pedestrians. When pedestrians cross the street they must adjust their situation awareness. They have to change their direction of movement, attention, and visual search pattern whenever they change their walking path firom the curb to the road. Consequently, many crashes occur because drivers fail... 

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