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Coal has been part of Wyoming's economy since the late 1800s and continues to have a major influence on the state. Since mining began, trends of rising and falling prices for coal have created economic instability. Currently, Wyoming's coal industry is experiencing a downturn, leading to lay-offs and financial hardship for the state and municipalities. The Wyoming legislature has attempted to invigorate the industry through several pieces of legislation. Some of these include increasing the purview of the Wyoming Infrastructure Authority, funding the Integrated Technology Center in Gillette, and preventing new taxation on the industry. Governor Matt Mead has prioritized diversifying not only the coal industry but also the state economy as a whole. Nationally the Trump Administration is attempting to revive the industry through the removal of regulations imposed by multiple agencies. While these measures are helping in some ways to make coal viable as an energy source again, the reality is that the coal industry globally is struggling. Government can only do so much to promote industry. Rather than market coal as an energy source, one company in Wyoming is proposing to refine and provide it as a feedstock for manufacturing carbon-based products. Ramaco Carbon, a Sheridan-based company, is in the initial stages of creating a large-scale research, development and manufacturing site with several tenants engaged in carbon-based manufacturing. Their efforts could change the future of coal in Wyoming.

A group of 92 male engineers, with comparison groups of 80 women and 55 human factors specialists, responded to an 18-item questionnaire covering various problems of potentially ambiguous display-control relations, labeling, and word usage. Some questions elicited strong commonality of response. Others illustrate response variability and group differences. Developed as a teaching aid, a questionnaire of this kind can also be used as a tool for exploring compatibility relations.

The legibility of displayed letters depends upon their size, or more accurately, their subtended visual angle at any viewing distance. Current design standards recommend letter heights in the range from 0.003 to 0.007 rad (10 to 24 mill of arc) for good viewing conditions, with 0.0015 rad (5 min) considered a lower limit based on normal visual acuity. A field study involving some 2000 measures for over 300 printed displays found a mean letter height of 0.0019 rad (7 min) at the limit of legibility, with over 90% legibility at 0.003 rad and virtually 100% at 0.007 radians.

In contrast with earlier research showing Lansdell numerals superior in legibility to conventional number shapes during brief exposure of single digits, the present study found that Lansdell numerals are read at least 15% more slowly than Mackworth or Elite numbers when groups of five symbols are scanned for a target digit, and are read 34% more slowly when the five digits in each group must be added. This lower readability indicates that Lansdell numerals should not be used in situations requiring interpretation of displayed numbers, i.e., should not be used for most display applications.

People scanned lists of hierarchically numbered items in order to perform various tasks. For tasks involving location of individual items, a list of format with complete numbering resulted in superior performance. For tasks requiring perception of list structure, an alternative format with implicit numbering was equally good if not better.

Twelve subjects scanned displayed prose passages to detect randomly inserted letter substitution errors. In comparison with steady displays, this check-reading task was performed 10% more slowly but with equal accuracy when the displayed material blinked at a 3-Hz rate. Although the potential value of blink coding confirmed in previous research is not questioned, the reduction in readability of blinking displays demonstrated in the present study suggests that some precautions must be taken in the practical application of this display coding technique.

Ten men scanned cathode-ray-tube displays to search for designated target items. Search time increased with increasing display density, and was 50% faster when a 3-cps blink was imposed on items of the target class. The blinking of nontarget items was almost equally effective, indicating that blink can be used either as an inclusion or exclusion code. In comparison with steady, nonblinking displays, search time was not significantly different for displays in which all items blinked, or in which a random selection of items blinked. It is concluded that for visual search tasks of the kind reported here, there is no marked deleterious effect of blink coding on symbol legibility, and no marked interference attributable to irrelevant blink.

Computer analysis indicates the feasibility of single-stroke keying for data entry of alphabetic names using the standard touch-tone telephone pad. In many practical job situations little ambiguity will result from the single-keying technique, and this ambiguity can be resolved under computer control.