bluuebunny/crossref_metadata_2025 huggingface dataset:
Icons vs. Alphanumerics in Pilot-Vehicle Interfaces
Authors: Camacho Monica J. , Steiner Bruce A. , Berson Barry L.
Published: January 2012

The effects on performance from the use of icons and alphanumerics in pilot-vehicle interfaces were investigated in an experiment. Varying numbers of single status display indicators were presented in both iconic and alphanumeric formats in fixed and random display positions across three levels of difficulty. Subjects' ability to maintain a tracking task while concurrently searching and selecting appropriate display indicators was tested. Results indicated that for all numbers of indicators presented, icons produced faster search and selection reaction times. Significant interactions were also found for format type and difficulty level. Questionnaire assessment revealed that subjects preferred the iconic to the alphanumeric formats. Implications for the design of aircraft interfaces and further research suggestions are discussed.
The Relative Effectiveness of Three Visual Depth Cues in a Dynamic Air Situation Display
Authors: Mazur Kim M. , Reising John M.
Published: January 2012

The purpose of this study was to evaluate the effectiveness of three visual depth cues, and combinations of these cues, in a dynamic air situation display. The study was conducted to help determine how best to display aircraft location to a pilot. Three different depth cues (stereo 3-D, aerial perspective, and familiar object size), were investigated. Additionally, two levels of display density (13 or 25 aircraft) were evaluated. The results of the study indicated that the number of depth cues, which ranged from zero to three, affected the subject's ability to determine aircraft location. Display density also affected performance. However, the particular type of depth cue did not have a differential effect. In other words, it makes a difference if one or two depth cues are displayed, but not the particular cues used.
Mental Models, Mental Workload, and Instrument Scanning in Flight
Authors: Hameluck Donald E.
Published: January 2012

This paper examined the correspondence between pilots' instrument scanning behavior during instrument approaches and their general knowledge (or “prototypical mental model”) of their information requirements and subjective reactions associated with procedural phases of the approaches. Factor analysis was used to characterize each of these two domains in terms of a set of underlying factors. The relationships between the factors of the instrument scanning domain and those of the mental model domain appeared to be based on the procedural requirements of the approaches (e.g., reduce airspeed and altitude).
A Secondary Analysis Comparing Subjective Workload Assessments with U.S. Army Aircrew Training Manual Ratings of Pilot Performance
Authors: Stewart John E. , Lofaro Ronald J.
Published: January 2012

The present research effort sought to determine the validity of subjective workload estimates for Aircrew Training Manual (ATM) tasks for the UH-60 helicopter generated via a modified Delphi technique. Delphi weights were found to predict performance ratings on the ATM tasks; ATM tasks associated with accidents also had higher Delphi weights than did those not so associated.
The Effects of Familiarization on the Comprehension of Synthetic Speech in Telephone Communication
Authors: Lauretta Donna J. , Rodman Robert D. , Antin Jonathan F.
Published: January 2012

Text-to-speech systems are currently used in a variety of telephone applications for remote access to information. While this form of synthetic speech may be cost-effective relative to digitized speech, the impoverished quality of the speech signal may adversely affect its comprehensibility in telephone applications. The primary objective of the present research was to investigate the amount of familiarization needed to achieve an asymptotic level of comprehension performance with high-quality synthetic speech presented in the telephone environment. Sixty-four male and female native English speakers listened to digitized natural and digitized synthetic sentences that contained relatively high and low-predictable components. Subjects provided truth-value judgments for which accuracy, response time and response certainty were measured. Results indicate that a high-predictable introductory message of approximately three relatively short sentences may improve comprehension performance of high-quality synthetic speech in some telephone applications.
How Do you Enter “D'Anzi-Quist” Using a Telephone Keypad?
Authors: Marics Monica A.
Published: January 2012

This study looked at the way users enter alphabetic information on a standard, 12 key telephone. Twenty subjects entered names on the telephone keypad using the one keystroke per letter method. Subjects were not given instructions on how to enter the characters Q, Z and other punctuation which do not appear on the keypad. Data were collected on the keys chosen for these special characters, and for keypress errors and name entry times. The results do not indicate a clearly preferred entry method for Q, Z and hyphen, however, apostrophes were likely to be skipped (not entered) by the subjects.
Designing a Help System Using a Goms Model: A Preliminary Method Execution Analysis
Authors: Elkerton Jay , Goldstein Steven J. , Palmiter Susan L.
Published: January 2012

The GOMS model (Card, Moran, and Newell, 1983) was used to develop the content of a help system from the goals, operators, methods, and selection rules needed to perform HyperCard™ authoring tasks. Three groups of 12 novice HyperCard users performed 28 authoring tasks using either the GOMS help system, an original help system developed by Apple® Computer, or no help at all (a control group). In the two help groups, users were provided the most complete help method and did not have to search for the help information. The results indicated that both help systems significantly decreased the time spent performing the authoring tasks when compared to the control group. Although a 23% decrease in execution time for GOMS users compared to original users was not significant, variance ratios confirmed that GOMS users, as a group, were more consistent when compared to original and control users. Also, GOMS users spent significantly less time per help display, translating the help methods into execution performance 78% more efficiently than original users. This result probably was due to the procedurally explicit and consistent help methods specified by the GOMS model.
Screen Design for Boolean Operators
Authors: Nolan Peter R.
Published: January 2012

Three studies from a text search usability program are reported. A logging study revealed the most frequent kinds of searches carried out by users. A laboratory study compared three user interface design alternatives accomodating these searches. A column layout with the logical operators AND, OR, and NOT as column headings, and which assumed parentheses by the spatial positioning of the search term, was significantly faster than the other two designs, and was also preferred by a majority of the subjects. An interview study indicated that users need a verification step prior to search submittal, and a thesaurus linked to the search term fields. There is a discussion of the limitation of each screen design and an evaluation of the methodologies used.
Streamlining the Design Process: Running Fewer Subjects
Authors: Virzi Robert A.
Published: January 2012

Recent attention has been focused on making user interface design less costly and more easily incorporated into the product development life cycle. This paper reports an experiment conducted to determine the minimum number of subjects required for a usability test. It replicates work done by Jakob Nielsen and extends it by incorporating problem importance into the curves relating the number of subjects used in an evaluation to the number of usability problems revealed. The basic findings are that (1) with between 4 and 5 subjects, 80% of the usability problems are detected and (2) that additional subjects are less and less likely to reveal new information. Moreover, the correlation between expert judgments of problem importance and likelihood of discovery is significant, suggesting that the most disruptive usability problems are found with the first few subjects. Ramifications for the practice of human factors are discussed as they relate to the type of usability test cycle the practitioner is employing, and the goals of the usability test.
Juggling Concern for Completeness and Consistency with Concerns for Flexibility and Adaptability Using Most
Authors: Carter James A.
Published: January 2012

The Multi-Oriented Structured Task analysis (MOST) methodology attempts to be most things to most of its users most of the time by balancing the needs of both system users and system designers for flexibility and adaptivity. The MOST methodology structures a task analysis and integrates it with other more formal specification methodologies including software engineering methodologies, human-computer interaction methodologies, and explicit user models. MOST stores these specifications in a knowledge base of four major interlinked foci for the information (users, tasks, data, and tools) and an optional foci (constraints) that can be linked to any of the major foci. The linkages in a MOST knowledge base facilitate the flexible structuring and restructuring of records. These linkages can model alternative designs and/or paths by which a system can adapt its interface while maintaining functional consistency. Various design heuristics (both software engineering and human factors) can be applied to an analysis recorded in a MOST knowledge base to assist in its transformation into a suitable design. The MOST methodology is designed to cooperate with and to assist the designer rather than to force the user to serve the methodology.
Effect of Touch Screen Target Location on User Accuracy
Authors: Leahy Michael , Hix Deborah
Published: January 2012

Users can be frustrated by touch screen applications that inaccurately record their touches. Enlarging touch sensitive regions can improve touch accuracy, but few specific quantitative guidelines are available. This paper reports on a controlled experiment that investigated the effect of target location and horizontal viewing location on user accuracy. Measurements showed that persons tended to touch below the target, with touch distance increasing as the target location moved down the screen. In addition, they tended to touch toward the sides of the screen. Using collected data for each of nine screen sectors, graphs were prepared that show the relationship between touch target size and expected accuracy. For example, a 36 mm2 target in the top left sector would be expected to accurately record 99% of its touches. The empirically-derived, quantitative guidelines will help designers create screens that decrease user errors and frustration.
The Effects of Structural and Overlay Design Parameters of Membrane Switches on the Force Exerted by Users
Authors: Sind Paula M.
Published: January 2012

Two experiments were conducted to evaluate the effects on applied force of structural design parameters and of feedback conditions inherent in the aesthetic overlay of membrane switch touchpads. In the first experiment which evaluated structure, 12 males and 12 females keyed 100 4-digit sequences into a computer using 6 of a total of 12 touchpads which differed in membrane ply thickness, spacer thickness, and spacer aperture diameter. The same task was completed by nine males and nine females in the second experiment, which evaluated feedback conditions inherent in flat, embossed, domed, embossed with dome, flat with escutcheon, and domed keycap aesthetic overlays. The results have important implications for the methods used for life-testing membrane switch touchpad devices and for the design of touchpads for minimizing user fatigue in extended-use keying applications.
Impact of Age-Related Play and Injury Patterns on Human Factors Criteria for Playground Equipment Safety
Authors: Ratté Donna , Morrison Melanie , Lerner Neil , Bellegarde Marie
Published: January 2012

About one-third of all public playground equipment injuries are sustained by children under 6 years of age. Injury data indicate that children in this age group are at particular risk of injuries to the head and face. A recent detailed analysis of playground equipment design issues (Ratté, Morrison, Lerner, Denham, and Johnson, 1990) formed the basis for an update and expansion of the Handbook for Public Playground Safety, published in 1980 by the Consumer Product Safety Commission. An important focus of this work was to develop recommendations that take into account the critical differences between preschool-age and school-age children with respect to the following factors: physical capabilities; anthropometric measures; play patterns; cognitive skills; and injury patterns and common injury scenarios associated with specific types of equipment. This paper illustrates how these factors were applied to the analysis of swing-related safety problems, and describes some of the difficulties involved in developing human factors criteria for playground equipment safety. Although specific design recommendations addressed the safety of each type of equipment, other issues were also of critical importance in evaluating each product's potential for injury, including use and fall zones around equipment, spatial relationships with other equipment and activities on the playground, separation of children of different ages, and adult supervision. These considerations sometimes represented conflicting safety concerns.
Knurls on Push and Turn Lids
Authors: Cranmer Laura , Konz Stephan
Published: January 2012

This study investigated the effects of knurling on exertable torque on “childproof” prescription lids; that is, where a “push and turn” action is required. Twelve lids with the same height (12.7 mm) were used. Six knurling designs were evaluated for two lid diameters (32 mm and 54 mm): a smooth lid, a lid with two levers, and lids with 7–8 knurls/cm, 4 knurls/cm, 2 knurls/cm and 1 knurl/cm. The 35 male and 13 female subjects pushed and turned the 12 lids in a clockwise direction against a torque meter. The effects of gender, size, knurl design, and the interaction of gender and size were significant. Males exerted 42% more torque than females. Subjects exerted 200% more torque on the 54 mm lids than the 32 mm lids. The interaction of size and gender showed that increasing lid diameter was more advantageous for males than females. The lid with two levers provided 54% more torque than the smooth lid for the 32 mm lid but only 21% more for the 54 mm lid. The knurl designs gave 4–15% more torque than the smooth lid.
An Examination of Flexible Group Work Spaces in the Open Office
Authors: Zimmer Linda , Cornell Paul
Published: January 2012

This paper examines the impact of flexible open office group work spaces on group work and workers. As a case study, two flexible group spaces were evaluated by means of a post occupancy evaluation. The evaluation methodology was driven by a series of seven hypotheses related to how the physical setting may impact group effectiveness in relation to group tasks, tools and work styles. The findings indicate that flexibility in open plan group work spaces is highly valued by the users.
“Offensible Space” — Law and Order Obstruction through Environmental Design
Authors: Atlas Randall
Published: January 2012

Defensible Space and Crime Prevention Through Environmental Design (CPTED) were the bright stars and catch phrases in the 1970's for crime prevention. Twenty one years latter, crime is increasing steadily. The law abiding community is being held captive to drug dealers, stressed out police, and over-extended budgets. Defensible Space strategies have not been integrated into the building community due to the lack of consensus, budget constraints, and the lack of power to implement improvements. One of the few successful applications of CPTED and Defensible Space principles have been well-to-do private sector housing, and criminal drug sites. This paper explores how the criminals have successfully applied Defensible Space principles to resist intrusion by outsiders and law enforcement creating “Offensible Space”. A study of 21 well known crime sites in South Florida was conducted. Environmental cues of surveillance, access control, and territoriality were observed and recorded. The findings reveal a remarkable adaptation on how it is that criminals are able to successfully implement Offensible Space concepts for illegal purposes.
Injury Severity and Likelihood in Warnings
Authors: Wogalter Michael S. , Barlow Todd
Published: January 2012

Two experiments examined the influence of injury likelihood and severity in warnings on product hazard perceptions (Experiment 1) and behavioral compliance (Experiment 2). In Experiment 1, participants were given a set of front panel labels for 10 household consumer products. Warnings on the labels were constructed by manipulating the likelihood (low vs. high) and severity (low vs. high) of injury. Labels lacking a warning served as controls. Participants rated the product labels under the guise of a marketing study in which most of the questions concerned product familiarity, cost, and label attractiveness. Only one question was of interest which probed the level of hazard posed by the products. The results showed that (1) the presence of a warning increased the products' judged level of hazard, (2) products with high severity warnings were viewed to be more hazardous than products with low severity warnings, and (3) likelihood of injury in the warnings had no influence on hazard perceptions.

Experiment 2 used a chemistry laboratory demonstration task to test the effects of injury likelihood and severity in a warning on compliance behavior (i.e., wearing gloves as directed by the warning). Greater compliance was shown when warned of a more severe injury, but only when the injury was of lower likelihood.

In general, both experiments showed that injury severity influences warning effectiveness to a greater extent than injury likelihood. The results suggest that to inform people of a hazard and to motivate them to comply with a directed behavior, product warnings should communicate the severity of consequences.
The Design of a Graphics-Based Traffic Information System Based on User Requirements
Authors: Gray Bruce G. , Barfield Woodrow , Haselkorn Mark , Spyridakis Jan , Conquest Loveday
Published: January 2012

This paper reports the results of several studies designed to investigate commuter behavior and decision making with the goal of obtaining functional requirements for a user-based advanced driver information system (ADIS). To achieve this objective, the following tasks were performed: (1) a large sample survey was administered to 9, 652 motorists commuting to a downtown location, (2) an in-depth interview was conducted focusing on the individual motorist's commute, and (3) a questionnaire was administered to investigate the relationship between various forms of graphical traffic information on commuter behavior and decision making. The information obtained from the above studies is being used to design traffic information screens that form the focal part of an ADIS.
Human Factors Participation in the Return to Work Process
Authors: Bowers-Carnahan F. Renae
Published: January 2012

In late 1989, LTV Aircraft Products Group instituted a Return To Work Committee to review the cases of UAW-represented employees who have been disabled and cannot function in their original job. The committee is new and is still formulating the details of the process, but industrial ergonomics has already been established as an important contributor. In LTV s process, Human Factors Engineering evaluates the employee's original job to determine whether it is, or can be modified to be, within his/her functional capabilities. The contributions of Human Factors to the LTV Return To Work Committee's process and potential problems are discussed. The success of the program is also discussed.
Performance Analysis of Acute Exposure to Hand-Arm Vibration among Underground Drillers
Authors: Hudock Stephen D.
Published: January 2012

The U.S. Bureau of Mines, the Ontario Mining Health and Safety Branch, and an underground gold mining operation cooperated in a research study to evaluate the pre-and post-shift response to hand-arm vibration (HAV) exposure among underground drillers. The acute effect of HAV exposure was evaluated using three distinct measurement tools, including a test of sensitivity to varying levels and frequencies of vibration using a vibrometry system, a test of hand strength using a grip strength dynamometer, and tests of both gross movements of hands and arms and fine fingertip dexterity using the Purdue Pegboard tasks. Paired T-tests found no significant differences between pre-shift and post-shift vibrometry scores among shifts. Right-hand pegging, assembly, and the combined pegging scores were significantly higher for the post-shift testing when shifts were combined. None of the three measurement tools used appeared to be adequately sensitive to determine the effects of acute exposure to hand-arm vibration.
Cost-Benefit Analysis of Usability Engineering Techniques
Authors: Karat Clare-Marie
Published: January 2012

A methodology for computing the value of iterative usability work is presented using data from a series of three usability tests of each of two software applications. The cost-benefit analysis methodology provides software development managers a basis for making pragmatic decisions about human factors work. The projected dollar value of the reduction in end user time on an application task based on data from the first to the third test is compared to the costs of the usability work. The analysis shows a 2:1 dollar savings-to-cost ratio for a relatively small development project and a 100:1 savings-to-cost ratio for a large development project. Sources of additional savings are examined. Methodological techniques employed during the iterative usability testing are highlighted and the tradeoffs concerning use of these techniques for human factors, software development schedule, and economic reasons are discussed. Cost-benefit analysis is one of several mechanisms that generate product management support for human factors work and may facilitate a better understanding of the value of incorporating human factors work in software development.
Computer Use in the Scientific Office
Authors: Miller Doug , Davis Donald D. , Elio Frank
Published: January 2012

The current research was designed to contribute to the study of scientists' computer use through the development of a linear predictive model of use. Nine variables were selected for study: computer experience, job requirements (profession, time spent on, and importance of 11 work activities), support system size, computer literacy, satisfaction with current tools, overall impact, the importance of computer literacy and skills to management, the importance of computer literacy and skills to colleagues, and interest in computers. There were three components to data collection: (a) on-line recording of participant computer use, (b) a questionnaire, and (c) a discussion period held immediately following completion of the questionnaire. Questionnaire measures were assessed for test-retest reliability and were developed to ensure content validity. Computer use was measured both with a computer-based measurement tool and with the study questionnaire. A cluster analysis on work activity data revealed three distinct clusters of scientists. A single capability with computers factor was derived from a factor analysis on computer literacy, computer experience, and interest in computers. Likewise, a single computer use factor was derived from a factor analysis on measures of use. A linear predictive model of profession + cluster membership + capability with computers accounted for 61 percent of the variance in participant computer use. These findings indicate that while scientists' computer use is determined by a complex set of inter-related variables, a great deal of the variance in scientists' computer use can be predicted from measures of job requirements (viz., profession, cluster) and capability with computers.
Electronic Performance Monitoring, Job Design and Psychological Stress
Authors: Rogers Katherine J.S. , Smith Michael J. , Sainfort Pascale C.
Published: January 2012

This study helps establish how electronic performance monitoring may influence employee physical strain levels through job design. It identifies job design variables which differ between monitored and non-monitored employees in the telecommunications industry (using discriminant function analysis). These variables' relationships to psychological stress outcomes were examined using multiple regression analysis. A group of 704 employees in three job categories (telephone operator {n=228}, customer service representative {n=230}, and clerk {n=246}) responded to a questionnaire survey mailed to their residence. Four hundred thirty-four of the respondents were monitored and 264 were not. The results indicated that the monitored employees had significantly higher levels of reported psychological stress than the non-monitored employees. The discriminant function analysis of job design variables showed that a variety of job design factors discriminated between monitored and non-monitored employees. High levels of workload, few lulls between periods of high workload, high levels of career/future ambiguity, poor relationships with supervisors, as well as low levels of task meaningfulness and completeness were significant predictors of psychological stress outcomes (tension, anxiety, depression and fatigue).
Factors Governing Performance in a Visual Interception Task
Authors: Fischer Susan C.
Published: January 2012

Two experiments examined factors governing performance in a dynamic spatial task requiring object interception. In the two experiments, several variables were systematically manipulated, including target trajectory, decision time, and interceptor to target speed ratio. In both experiments a systematic linear relationship between actual response time and decision time was observed. The slope of this function was less than 1, indicating that subjects were less sensitive to variation in actual decision time than an “ideal” observer. Performance patterns further indicated that subjects utilized both speed and distance information to guide their judgements, but failed to adequately incorporate speed information.
An Analysis of Performance in a Two Object Arrival Time Task
Authors: Law David
Published: January 2012

Three experiments investigated factors affecting performance in relative arrival time judgments. Male and female subjects predicted which of two moving objects in a computer controlled display would arrive first at a target. The relative arrival time of the objects, speed ratios, and path relations were varied. Results of the first experiment included a systematic pattern of error associated with an apparent distance bias. The second and third experiments added relative speed and distance judgment tasks. It was found that the levels of relative speed and distance employed in the arrival time task were discriminable and that performance in the speed and distance tasks was moderately predictive of performance in the arrival time task. It was also found that despite the evidence of a distance bias subjects did attempt to integrate speed related information in their decisions. The third experiment assessed the stability of performance in each of the tasks over time and provided evidence of individual differences in the ability to coordinate information.
Automotive Maintenance and Safety Preparedness among Drivers: Aspects of Age and Gender
Authors: Mayer David L. , Laux Lila F.
Published: January 2012

Almost every motor vehicle in use today came with a manufacturer recommended maintenance schedule. Many automobile manufacturers expect the owner (or driver) to perform certain first-line maintenance tasks on his or her own vehicle. This paper examines automobile drivers' knowledge of and preparedness to deal with many of these maintenance tasks as well as some emergencies which can arise as a result of their neglect. Relative differences between the genders are discussed as are differences among age groups. A set of non-driving maintenance functions commonly described in owner's manuals was selected for study. A survey was designed to measure drivers' knowledge with regard to these maintenance functions and other safety knowledge. The instrument also asked a number of questions designed to determine what types of safety equipment the drivers routinely carry with them as well as what types of other maintenance the subjects performed on their own cars. Subjects were 166 licensed male and female drivers between the ages of 16 and 92. Results indicate that many drivers may not be safely performing these tasks and, further, may not have the critical knowledge (and, in some cases, equipment) to perform them safely or to deal with common vehicle emergencies.
Gender Differences in Traffic Accident Risk Perception
Authors: DeJoy David M.
Published: January 2012

Excessive optimism has often been implicated in the disproportionate involvement of young males in traffic crashes. In this study, male and female students (ages 18–24) were asked to judge their relative driving safety, skill, and accident likelihood. They also rated 15 risky driving behaviors in terms of frequency, seriousness, accident potential, and apprehension likelihood. Driving experience/history data were also collected. Substantial optimism was evident in both sexes, but males tended to be more optimistic, especially when judging their driving skill. Males and females held similar perceptions concerning the frequencies and apprehension likelihoods of the risky behaviors, but males perceived the behaviors as less serious and less likely to result in accidents. Regression analyses showed that considerably more variance in optimism could be explained for males than females.
Requirements for An Aircraft Mishap Analysis System
Authors: Courtright John F.
Published: January 2012

As a result of long-standing, systematic mishap investigation and analysis practices, the U.S. Air Force has been able to achieve and maintain a consistently low level of aircraft mishaps. However, up to 90 percent of these mishaps are associated with human factors problems. In recognition of the need for better tools to identify the complex nature of human contributions to mishaps, the Air Force has established an Aircraft Mishap Prevention program to develop the capability to apply information gathering processes, sophisticated analysis techniques, and hypothesis generation support tools to help recognize and correct deficiencies in equipment design, training, and operational practices which contribute to mishaps. This presentation provides information on the scope, content, and approach to providing the expected full capability by 1993.

One challenge in the design of the program features was the need to accommodate a range of analysts skilled in mishap investigation practices but naive with respect to human factors considerations in analysis. This will be met by incorporation of supporting skilled staff and special purpose software which will aid these analysts to identify and evaluate human factors considerations in individual mishaps and across all mishaps. This presentation reviews human factors considerations in the software support features which will assist the analysts perform analyses and develop and evaluate countermeasures. Considerations and cautions in developing selected human-computer interaction is reviewed, with attention given to features to be incorporated to lead the analyst and to provide him with questions and considerations which must be resolved before a workable hypothesis can be developed or evaluated.
Vigilance in Transport Operations. Field Studies in Air Transport and Railways
Authors: Mollard R. , Coblentz A. , Cabon Ph.
Published: January 2012

Human operators in transport operations are often confronted to monotony, boredom and irregular work schedules. This situation seems to be more and more acute because of the growing automation of the systems. This paper presents the method and the first results of two field studies on the vigilance and performance of plane pilots and train drivers. The aim of these studies is to identify the factors that can modify the vigilance and to elaborate some specific solutions for reactivation. The method is based on the collection of physiological data in the field and on the task observation of the operators. The recorded physiological data (EEG, EOG), permit an evaluation of the vigilance and the rest-activity cycles. For pilots, results show a high occurence of decreases of vigilance, in particular during the phase of low workload (i.e. during the cruise). Furthermore it was shown that these periods of lowered vigilance can occur at the same moment for two crewmembers. For the train drivers a great number of decreases of vigilance were also observed. These decreases of vigilance were observed although the operators had sometimes a high level of activity. It was also noted a direct relation between the sleep duration and the rest onset. This study would provide some means to reactivate the train drivers when necessary and to improve the system of rotating work schedules.
The Army Manprint Idea: (Integrated Decision/Engineering Aid)
Authors: Malone Thomas B. , Heasly Christopher C. , Eike David R.
Published: January 2012

The US Army Human Engineering Laboratory (USAHEL) is developing an approach to the application of MANPRINT in the context of the Materiel Acquisition Process (MAP). This approach includes: 1) a MANPRINT roadmap, consisting of a formal and standard process for accomplishing MANPRINT at each phase of the MAP and which is tied to the activities, products and events of the MAP; 2) a tool kit consisting of a set of automated tools needed to implement the roadmap in a cost-effective manner; and 3) a repository of all pertinent information, and techniques for accessing all available information - available at the user's workstation irrespective of the original source.

The driving requirement for the USAHEL approach to HFE/MANPRINT is for integration. This includes: integration of the HFE/MANPRINT process into the Materiel Acquisition Process; the integration of HFE/MANPRINT tools into the process; the integration of HFE/MANPRINT tools and data bases in terms of data import and export; the integration of HFE/MANPRINT tools among themselves in terms of data import and export; and the integration of HFE/MANPRINT domains including HFE, manpower, personnel and training, system safety, and health hazard assessment.

The USAHEL approach to MANPRINT in the early stages of materiel development is to base the process for accomplishing MANPRINT on the HFE front-end analysis methodology as described in MIL-H 46855B. USAHEL, under contract with Carlow Associates Incorporated, is developing a MANPRINT standardized and formalized process tied to the events, activities, products and milestones currently for the first two phases of the MAP and incorporating a set of automated tools and information system to support the application of the MANPRINT process. The system, including the process, associated tools and information resources, have been designated the USAHEL MANPRINT Integrated Decision/Engineering Aid or IDEA.

IDEA includes a HFE/MANPRINT standardized and formalized process tied to the events, activities, products and milestones of each phase of the Materiel Acquisition Process (MAP) and incorporating a set of automated tools to support the application of the HFE/MANPRINT process. The process and associated tools have been completed for the Program Initiation Phase IDEA (prior to milestone 0) and the Concept Exploration Phase IDEA.

The elements of the IDEA system, as described in this paper, are: the HFE/MANPRINT process; an integrated HFE/MANPRINT information system; automated HFE/MANPRINT analysis tools; HFE/MANPRINT analyst productivity enhancement tools; HFE/MANPRINT information tools; a report generator for producing HFE/MANPRINT plans and reports; and, the user.
Using HSYS in the analysis of Human-System interactions: Examples from the offshore petroleum industry
Authors: Harbour Jerry L. , Hill Susan G.
Published: January 2012

In an attempt to better understand the interactional relationship between humans and operational systems, HSYS was developed. The HSYS methodology provides a systematic process for analyzing Human- SYStem interactions in complex operational settings. HSYS focuses on system interactions from the human's perspective and is built around a linear model of human performance, termed the Input-Action model. According to the model, all human actions involve, to varying degrees, five sequential steps: Input Detection, Input Understanding, Action Selection, Action Planning, and Action Execution. Based on the Input-Action model, a series of flowcharts, supported by detailed “topical modules,” have been developed to analyze each of the five main components in depth. During initial validation efforts, the HSYS methodology was used to analyze 28 accidents which occurred in the offshore petroleum industry from 1980 — 1989. Although numerous factors contributed to the various accident sequences examined, one frequently identified problem was a lack of situational awareness by crew members either immediately preceding the accident or during the actual accident sequence itself. A major contributor to this lack of awareness was inadequate input detection, caused by either inadequate input recognition, inadequate input discrimination, or inadequate attention. In most instances, the root causes for these inabilities were associated with inadequate sensor/display arrays and/or poor human-machine interface design and engineering.
Assessing Icon Appropriateness and Icon Discriminability with a Paired-Comparison Testing Procedure
Authors: Magyar Regis L.
Published: January 2012

Traditional methods of evaluating icon comprehension and discriminability have relied on a sequence of multiple screening tests to measure various aspects of icon meaning, image content, and the user's perception of the icon. The most frequently used procedures have been the icon appropriateness test to determine the best conceptual design from a group of icon candidates, followed by the icon matching test to ensure that individual icons are not confused with others in a set. This paper describes an automated paired-comparison test procedure that provides reliable measures of both icon appropriateness and icon discriminability using the same test method with a single metric. The procedure was validated in two experiments involving the design and evaluation of two different mouse-pointer icons. In Experiment 1, the procedure was used as an icon screening test to determine the most appropriate and meaningful icon that best represented each concept from two different sets of proposed icon variants. In Experiment 2, the same procedure was then used to confirm the discriminability of the final icon selections, and to verify the accuracy of results from the initial appropriateness test.
An Alternative Measurement Paradigm
Authors: Meister D.
Published: January 2012

If human factors measurement techniques are inadequate to provide requisite data, a new measurement paradigm must be adopted to supplement traditional research strategies. One is proposed which focusses on the selection of important research questions for which data are now not available. In addition, the use of experientially derived data as the first step in data collection is suggested. A five point programme to be implemented over a period of years is proposed.
Verbal Protocols as a Research Tool in Human Factors: Symposium Abstract
Authors: Deffner Gerhard
Published: January 2012

The five papers in this symposium are aimed at providing empirical background for addressing the questions of how useful, and also how usable, verbal protocol methodology is within the field of human factors. Research approaches range from experimental to case study, and topics range from comparative assessment of procedural variations in verbal protocols, to their application in unique task domains. Both types of research have shown encouraging results, which will be discussed in terms of potential standardization of procedure, and of wider use and application of verbal protocol methodology.
Concurrent versus Retrospective Verbal Protocol for Comparing Window Usability
Authors: Bowers Victoria A. , Snyder Harry L.
Published: January 2012

A traditional concurrent verbal protocol method was compared to a heavily cued retrospective verbal protocol in which users were presented with a video tape of their performance to help them recall their thoughts after task completion. The two methods of protocol were employed in a comparison of two different size monitors. Subjects were required to complete 12 tasks which varied in the number of windows required simultaneously on the monitor. The subjects' performance, as measured by steps to completion, task completion time, and errors committed, was compared across monitors and protocol methods. Subjective data were also collected in the form of task difficulty ratings, as well as a global measure of user satisfaction. Verbal data were compared to assess any information differences due to the methods of collection or the monitor sizes.

No performance or subjective differences were found between the two protocol methods. The kinds of information gathered were quite different for the two methods, with concurrent protocol subjects giving procedural information and retrospective protocol subjects giving explanations and design statements. Performance data, as well as subjective data, indicated that on tasks that require that one or two windows be present simultaneously, there were no differences between the two monitor sizes. As the number of simultaneous windows increased, however, the large monitor's advantages became apparent. Tasks which require that four windows be present simultaneously were judged to be easier and required fewer steps on the large monitor than on the small monitor.
Workload and Strategic Adaptation under Transformations of Visual-Coordinative Mappings
Authors: Caird J.K. , Hancock P.A. , Wade M.G. , Vercruyssen M.
Published: January 2012

Six right-handed male volunteers performed a bi-manual pursuit tracking task. Unknown to the subject, the mapping between both the absolute and relative motions of each control lever changed between trials, and could also change within a trial. There were four conditions which remained constant within a trial and four others which switched between combinations of the first four mappings. These eight total mappings could be performed under either a fast or slow target speed giving sixteen possible conditions, the order of administration of which was randomized across the subjects. Performance was assessed through the use of root mean square error (RMS) and percent time-on-target (TOT). Workload was derived from subjective report using the NASA Task-Load Index. Performance results differentiated three different groups within the mappings. The first group represented conditions in which despite scaling factors, the movement of the cursor remained consistent with the movement of the controls and was directly mapped. The second group, consisting of only two conditions, also presented internal consistency except that the movements of the cursor were mirrored in the movements of the controls, a direct but inverted map. The third group represented those conditions in which at least one period of performance decoupled the actions of the two controls. In general, workload distinguished the ordering of difficulty of the conditions, except that there was evidence of dissociation between performance and subjective evaluation in the three most difficult decoupled conditions. Verbal report of performer strategic behavior was elicited. Each line of evidence is considered in the attempt to understand how subjects explored the perceptual-motor space for strategic solutions when presented with the autonomy to do so.
Validation of a Driving Simulation Facility for Instrument Panel Task Performance
Authors: Kurokawa Ko , Wierwille Walter W.
Published: January 2012

The purpose of this study was to compare driver performance of 17 conventional automotive instrument panel (IP) tasks on the road and in the driving simulator and to validate use of the simulator in evaluation of an IP design.

Introduction of random crosswind was shown to influence the driving workload in the simulator. Comparisons of the visual attentional and manual demand measures demonstrated that a driving environment close to that in the car is provided by the simulator at zero crosswind level and that the driving simulator can be used to evaluate automotive IP designs.
Applying Knowledge Engineering to Training and Technology Transfer
Authors: Klein Gary A. , Crandall Beth
Published: January 2012

“Knowledge engineering” refers to the process of getting rules out of the heads of experts and into expert systems. A broader field include a variety of “low technology” applications. If we think of knowledge as a valued resource, analogous to petroleum, this suggests four aspects of knowledge engineering: (a) locating sources of expertise in organizations; (b) assaying the cost/benefits of engineering the expertise; (c) acquiring the knowledge; and (d) codifying the knowledge. In this paper we discuss knowledge engineering strategies and applications beyond expert systems.
Knowledge Acquisition and Representation for the Systems Test and Operations Language (STOL) Intelligent Tutoring System (ITS)
Authors: Seamster Thomas L. , Eike David R. , Ames Troy J.
Published: January 2012

This presentation concentrates on knowledge acquisition and its application to the development of an expert module and a user interface for an Intelligent Tutoring System (ITS). The Systems Test and Operations Language (STOL) ITS is being developed to assist NASA control center personnel in learning a command and control language as it is used in mission operations rooms. The objective of the tutor is to impart knowledge and skills that will permit the trainee to solve command and control problems in the same way that the STOL expert solves those problems. The STOL ITS will achieve this objective by representing the solution space in such a way that the trainee can visualize the intermediate steps, and by having the expert module production rules parallel the STOL expert's knowledge structures. This approach has resulted in a knowledge acquisition process that places a great emphasis on both the domain expert's knowledge structures and solutions steps. Concept sorting tasks combined with scaling analysis techniques are being used for organizing and analyzing domain concepts. These techniques have been used to identify the critical STOL commands, the related concepts, and significant problems that will direct the design of the tutor's user interface as well as the production rules of the expert module.
Development of a Part-Task, CBI Trainer Based upon a Cognitive Task Analysis
Authors: Redding Richard E. , Lierman Bruce
Published: January 2012

This paper describes the task analysis procedures and data obtained to support development of a part-task trainer for a CBI military training system (as well as various training aids and recommendations), and the trainer design and evaluation. This was part of a two-year R&D program which was unique in that the trainer was designed based upon data derived from an integrated task analysis methodology which incorporated both cognitive and behavioral methods. Because the task to be trained, electronic warfare, is an area with a complex conceptual base and heavy decision-making components, the task analysis was primarily cognitive. The task analysis provided information about expert versus novice mental models, and effective heuristics and algorithms for problem solving.