bluuebunny/crossref_metadata_2025 huggingface dataset:
The Relationship between Occupational Musculoskeletal Discomfort and Workplace, Personal, and Trunk Kinematic Factors
Authors: Allread W. Gary , Marras William S. , Fathallah Fadi A.
Published: January 2012

Little research exists that quantifies joint kinematics and associated musculoskeletal discomfort. Therefore, the main objective of this study was to investigate the relationship between musculoskeletal discomfort and trunk kinematic factors, workplace factors, and personal factors of those performing manual materials handling jobs in manufacturing environments. An industrial database of 337 subjects was used in this study. The results showed that the prevalence of reported low-back discomfort was 36.5%. The findings suggested that both workplace factors and kinematics were related to an employee's reported discomfort. Generally, physical parameters were associated with overall discomfort (‘No’ or ‘Yes’), whereas trunk kinematics seem to be associated with discomfort of specific body parts. The magnitudes of these associations were not large, implying that multifactorial models that include other factors, such as psychosocial indicators, in addition to those studied here, may further explain discomfort reporting.
Low Back Disorder Risk and Spinal Loading during Patient Transfer
Authors: Marras W. S. , Davis K. G. , Kirking B. C. , Bertsche P. K.
Published: January 2012

Patient handlers suffer from low back injuries at an alarming rate. While many have found patient handling to be associated with incidences of low back pain, there has been limited research quantifying the risk for the specific tasks performed by the patient handlers. The current study used both a risk evaluation system (Low Back Disorder risk model) and a biomechanical model (EMG-assisted spinal loading model) to quantitatively evaluate risk of LBD during patient handling. Seventeen subjects (twelve experienced and five inexperienced) performed several patient handling tasks. The patient transfers were between bed and wheelchair (fixed and removable arms) and between a commode chair and hospital chair. A “standard” patient (a 50 kg cooperative female; non-weight bearing but had use of upper body) was used in all patient handling tasks. Overall, patient handling was found to be an extremely hazardous job that had substantial risk of causing a low back injury. There was significant risk when transferring the patient with either one or two patient handlers. However, the greatest risk was associated with the one-person transferring techniques. The actual task performed had limited effect on the risk of LBD and the three-dimensional spinal loads. Even the safest of tasks (evaluated in this study) had significant risk. These findings suggest that the only feasible means to control risk would be to provide mechanical lift assists devices.
Impact of Total Quality Management on Work Environment Dimensions: An Empirical Study in the Public Sector
Authors: Taveira Alvaro D. , James Craig A. , Karsh Ben-Tzion , Sainfort François
Published: January 2012

The integration of Total Quality Management (TQM) and human factors has received increasing attention. In particular, the question of how TQM affects macroergonomic issues such as work environment dimensions (i.e. organizational design and culture) needs to be addressed. To this end, this study examines how TQM elements, as defined by the Malcom Baldridge Award, affect four work environment variables. The work variables, Supervisor Support, Task Clarity, Task Orientation, and Innovation, were selected for their theoretical relationship to TQM. Overall, the results indicate that as a group the TQM elements significantly predict the four work environment dimensions. Specific relationships between individual elements of TQM and the work environment dimensions are discussed, and directions for future research are proposed.
Influence of Organizational Culture in Europe on Perceptions of the Role of POS Technology in the Store
Authors: Hoffman Mark S. , Cohen M. , Bussemakers Myra P. , de Gruil Rasmus
Published: January 2012

Point Of Sale (POS) technology in supermarkets provides a common structure for fiduciary and organizational management, associate behaviors, and consumer interactions. Macroergonomic studies with two large European supermarket companies in Germany and Italy were completed. These studies included in-store observations, transaction processing measurement, associate and store management focus groups, and corporate management interviews. The store analyses revealed that organizational communication, social traditions, ergonomic standards, and legal restrictions were perceived barriers preventing the use of new technology to transform their business. In addition, conjoint analyses were conducted to determine technology solutions most critical to managing the business, and the expected benefits of implementing that technology. Results indicated that the North American retail model that uses new technology as the change agent of organizational does not directly apply to European supermarket retailers.
Integrating Micro- and Macro-Ergonomics
Authors: Gilmore David J. , Millard Derek
Published: January 2012

Understanding how a new piece of technology fits into a user's working environment is perhaps the classic definition of human factors or ergonomics – a view which fails to address the role of the organization in optimizing this fit. This paper presents a framework which tries to address this failure. The framework (the Dynamic Dilemmas model) is dynamic in that components of the framework are responding in real time to the behavior of other components – over and above any natural tendency they may have to develop and change on their own. And it is dilemma-based in that each component has its own needs and limits, not all of which can be met simultaneously, creating tricky choices concerning accommodation and optimization.

In this framework traditional usability is a part of a complex process optimizing the three-way fit between people, technology and organizations, with the fit being assessed in relation to the activities, skills, limits, needs, philosophy and whims of the people, technology and organization.
The Corruption of a Measurement System Due to Unintentional Bias: A Preliminary Macro-Ergonomic Study
Authors: James Matthew R. , Beruvides Mario G.
Published: January 2012

For the better part of the century, researchers have been analyzing the effect of an external prompt on human behavior. The phenomenon described by previous research has been dubbed the Pygmalion effect. This study looks at the effect an external prompt has on subsequent human behavior in a different setting than traditional Pygmalion studies. It examines the reaction of humans to external prompts in a measurement setting. The primary hypothesis of the research states that in a measurement system, indications about the expected outcome of inspections can lead people to inadvertently change their measurement techniques such that their results are significantly skewed toward the bias value compared to an unprompted group. The study was performed on 24 college students, measuring corruption in two different types of measurement systems, a rigid mechanical system and a visual inspection system. In two of the four measurement tasks in the rigid mechanical system, the evidence supported the hypothesis that a bias can be introduced. In the visual inspection system, each of the two measurement tasks supported the existence of an unintentional measurement bias. This study presents a challenge to the objectivity of measurement systems, which is a generally accepted, and poses several research questions from which future studies can be spawned and is a concern to researchers and practitioners interested in this aspect of macro-ergonomics.
Integrating User-Centered Design within a Virtual Product Development Organization: Observations from the Field
Authors: D'Souza Melroy E. , Dykstra Dean , Poole Anton
Published: January 2012

Currently, flexibility and time to market have become the new keys to product development. The need for versatility, low overheads, and direct customer communication has led to the birth of an emerging breed of organizations that employ a virtual product development model (VPDM). This paper explores the role of user-centered design within a VPDM being used in an actual industrial organization, and is based on the experiences of the authors working in that organization. It also discusses possible user-centered evaluation methods, and the factors that influence their use in this model. Finally, it provides recommendations for a more seamless integration of user-centered design within this model.
The Influence of Job Factors in the Introduction of Rest Breaks for Intensive Data Entry Work
Authors: Conway Frank T.
Published: January 2012

The study examined the relationships that psychosocial factors of work, psychological state, and personal factors had on musculoskeletal discomfort for intensive data entry work. A unique feature of this study was that the factors were measured at two locations which were implementing a new restbreak schedule. This schedule provided five minute hourly breaks in addition to two midshift breaks and a lunch break. Results indicated that psychological mood had a direct influence on musculoskeletal discomfort and that psychosocial aspects of work were more of an indirect influence on discomfort. These findings suggest tentative support for theoretical models of working conditions and health proposed by Smith and Carayon (1996) and Sauter and Swanson (1996). The results highlight the importance of psychosocial aspects of work on psychological mood state in a very narrowly defined data entry task performed uniformly by the employees. This may suggest that future intervention research needs to take into account the characteristics of the working environment and how they relate to employee health.
Results of Accessibility Analysis of Html and the Implications for Future Information Technologies
Authors: Chisholm Wendy , Vanderheiden Gregg C.
Published: January 2012

For the past four years, we have been examining how to make the WWW accessible for people with disabilities. This has involved gathering information through interviews, interactions with users having difficulty accessing the Web, creation and investigation of experimental Web pages and solicitation of feedback from demonstrations. The results show that the problem cannot be solved solely by modifications to Web pages. User agents (browsers), protocols (e.g., HTML) and assistive technologies need to change also. Regarding HTML pages, the results show the need to provide alternative forms of information and meta-information, elements to avoid, and the proper uses of HTML elements. In addition to making pages more accessible to people with disabilities, these measures also facilitate access by pocket browsers, indexing mechanisms, intelligent agents, and voice input/output access to the Web, as well as increasing the usability for all users.
Relative Importance of Different Verbal Components in Conveying Hazard-Level Information in Warnings
Authors: Young Stephen L. , Wogalter Michael S.
Published: January 2012

Participants rated 18 different warning-type statements describing various hazardous scenarios. The components of the statements were manipulated according to five variables: duration of exposure to the hazard, quantity of exposure to the hazard, likelihood of injury, severity of injury, and duration of injury. The relative importance of these variables in influencing hazard ratings was evaluated. The component describing injury severity was by far the best single predictor of hazard ratings (accounting for almost 78% of the hazard variance). Injury duration contributed an additional 15% of the variance. These results suggest that people consider the dimensions of injury severity and duration when evaluating the degree of hazard conveyed by warning text. Using these dimensions, warning text could be calibrated to the level of actual hazard to convey a better sense of hazardousness.
Perception of Risk in Automobiles: Is it Accurate?
Authors: Leonard S. David , Karnes Edward W.
Published: January 2012

Consumer concern with safety may be nullified because understanding of hazards associated with uses and misuses of products is often inadequate owing to lack of understanding relevant physical principles. These studies examined the public's understanding of hazards associated with automobiles. Recent safety advances have included passive restraint systems to increase the likelihood of buckling up. Such systems are usually passive/active systems, because lap belts must be manually buckled. Not buckling the lap belt may cause the system to become an injury-producing system rather than an injury-preventing system. Without lap restraint severe neck injuries and possible ejection from the vehicle can occur. Similar problems are posed by other seat belt behaviors. Surveys of general knowledge of these problems and of problems associated with the temperatures occurring in vehicles exposed to solar radiation indicated significant knowledge gaps. Suggestions are made for added warnings and informational programs to ameliorate the situation.
To Ph.D. or Not to Ph.D.? That is the Question!
Authors: Schoenfeld Victoria S. , Shapiro Ronald G. , Brown Megan L. , Jahns Dieter W. , Andre Anthony D. , Lund Arnold M. , Eggemeier F. Thomas , Cooke Nancy J.
Published: January 2012

Is a master's degree sufficient for a successful career in human factors, or is a doctoral degree necessary? This question has been a recent cause for discussion, especially among graduate students. In order to address this issue, the Old Dominion student chapter of the HFES developed some questions regarding the relative advantages of both degrees. Panelists were selected based on their experience with differing degrees. Megan Brown and Dieter Jahns are both practitioners who have master's degrees. Dieter is also Executive Director of the Board of Certification in Professional Ergonomics. Anthony Andre and Arnie Lund are practitioners, but both have doctoral degrees. Anthony is also an Adjunct Professor of Human Factors and Ergonomics at San Jose State University. In addition, Nancy Cooke and Tom Eggemeier are faculty members who have doctoral degrees. Tom teaches at a master's level institution while Nancy teaches at an institution that offers both master's and doctoral degrees. At the HFES panel session, panelists will focus on answering questions from the audience.
The Effect of Pacing and Explicit Costs on Human Decision Making Performance in Inspection
Authors: McDonald Tom , Gramopadhye Anand K.
Published: January 2012

Decision making is a critical component of visual inspection and a primary determinant of inspection quality. Previous studies in inspection have shown that pacing and costs have an effect on decision performance. The objective of this study was to evaluate human decision making performance under different conditions of pacing and cost tradeoffs. The study utilized twelve subjects who performed a decision-making (line judgment) task under paced and unpaced conditions and under various reward and penalty structures associated with various decision making outcomes (hits, correct accepts, false alarm, misses). The results were analyzed using Signal Detection Theory (SDT) measures of sensitivity and response criterion. Explicit costs had a significant effect on the response criterion, whereas pacing had a significant effect on the sensitivity.
User Preferences for Information Types in Advanced Traveler Information System Applications
Authors: Lerner Neil , Huey Richard , Zador Paul , Harpster Jeff , Duncan Doug
Published: January 2012

This experiment addressed the types of ATIS information travelers prefer to acquire, and how the information influenced route choice. Hypothetical trip scenarios provided information such as primary and alternative routes, time of day, current weather, trip purpose, etc. The participant had a set of from 9 to 16 sealed envelopes for each scenario, labeled as to the type of information inside. The participant opened as many envelopes as desired, in any order, to reach a decision as to what route to take. Participants typically only acquired three items of information, even though there were no constraints on information acquisition. “Incident location” was the most frequently selected, and most often opened first, but “delay” was most often cited as the most important item. Estimated travel times on the primary or alternate route were sought by some participants. Cluster analysis revealed three primary groups of individuals in terms of common information strategies. The findings are interpreted in terms of implications for the design of ATIS messages.
A Stopping-Distance Model for Driver Speed Decision Making in Curve Approach
Authors: Levison William H. , Kantowitz Barry H. , Moyer M. Joseph , Robinson Mark
Published: January 2012

One of the high priority research areas of the Federal Highway Administration is the development of the Interactive Highway Safety Design Model (IHSDM) that will allow highway designers to explicitly consider the safety implications of design decisions from the planning stage through the final design stage. The IHSDM will include a simulation model of driver/vehicle performance, which will contain a model for driver speed decision making as an important functional element. The speed decision model described in this paper requires two perceptual activities: (1) locate a target point a fixed radian distance into the idealized curve, and (2) estimate the stopping point given the current velocity and desired or current longitudinal deceleration. The control task becomes that of maintaining coincidence between the stopping and target points up to the point of curve entry. Correlation between model predictions and experimentally-observed trends of driver behavior is demonstrated.
The Effects of Age and Atis Use on Driving Performance: A Simulator Study
Authors: Fox Jean E.
Published: January 2012

Advanced Traveler Information Systems (ATIS) are in-vehicle computer systems that provide travel-related information (e.g., navigation assistance) to automobile drivers. ATIS has great potential to help drivers save time and money by leading them to their destination efficiently. However, there are great concerns that ATIS may interfere with driving performance. This study looked at the effects of ATIS use and the driver's age on driving performance in a high-fidelity driving simulator. The results indicate that ATIS use led to degraded driving performance in several measures. However, in some cases, the effects depended on age. Older drivers tended to be more cautious, while younger drivers tended to be more careless. These results suggest that ATIS systems and training materials may need to address the age-related differences in ATIS use and driving performance.
The Evaluator Effect in Usability Studies: Problem Detection and Severity Judgments
Authors: Jacobsen Niels Ebbe , Hertzum Morten , John Bonnie E.
Published: January 2012

Usability studies are commonly used in industry and applied in research as a yardstick for other usability evaluation methods. Though usability studies have been studied extensively, one potential threat to their reliability has been left virtually untouched: the evaluator effect. In this study, four evaluators individually analyzed four videotaped usability test sessions. Only 20% of the 93 detected problems were detected by all evaluators, and 46% were detected by only a single evaluator. From the total set of 93 problems the evaluators individually selected the ten problems they considered most severe. None of the selected severe problems appeared on all four evaluators' top-10 lists, and 4 of the 11 problems that were considered severe by more than one evaluator were only detected by one or two evaluators. Thus, both detection of usability problems and selection of the most severe problems are subject to considerable individual variability.
Instructor Use of Eye Position Based Feedback for Pilot Training
Authors: Wetzel Paul A. , Anderson Gretchen M. , Barelka Barbara A.
Published: January 2012

We conducted an 18 month study on the implementation and evaluation of a portable eye tracking system in a training environment. The system was used by F-16 simulator instructors to provide instructional feedback to F-16 student pilots during flight simulator training missions. The head-mounted components of the eye tracking system consist of a two-dimensional eye position measurement system and a miniature video scene camera. When displayed on a video monitor, a cursor corresponding to the student's line of sight allows the instructor to follow the student's visual scan pattern. The portable system can be used in a number of environments and applications to objectively assess visual behavior, to develop effective visual behavior, and to enhance training. In addition, the companion, real-time, automated analysis system can analyze, quantify, and summarize scan path behavior from recorded videotape.
Guidelines for the Use of Multimedia in Instruction
Authors: Williams James R.
Published: January 2012

The use of multimedia in instructional presentations has mushroomed in recent years due to the increased capabilities of computers and the inclusion of multimedia capabilities in most CBT authoring systems and presentation tools. While providing a wealth of opportunity to instructional developers, multimedia is often used ineffectively and may cause a decrease in learning performance. Many claims have been made as to the added effectiveness that multimedia can bring to training programs and presentations. The purpose of this paper is to provide researched-based guidelines for the use of multimedia that can be used by multimedia developers that may not be instructional technologists.
Aftereffects from Virtual Environment Exposure: How Long do They Last?
Authors: Stanney Kay M. , Kennedy Robert S.
Published: January 2012

The duration of the aftereffects from virtual environment (VE) exposure are not well characterized to date. Yet information concerning the incidence and enduring nature of these effects is essential to delimit the effective and safe use of VE technology. This study examined the aftereffects from VE exposure after three different exposure periods ranging from 15 to 45 minutes. Sixty participants were randomly assigned to one of the exposure periods, twenty to each condition. Sickness symptomatology, eye-hand coordination, and postural stability were measured before and after exposure. There were five measurements taken after exposure at 15 minute intervals. The results from the sickness symptomatology have been analyzed to date and show significantly higher symptomatology that persists for the entire post-exposure period in which measurements were taken. One hour after exposure the Total Severity of symptoms were 12 times higher than pre-exposure levels. Examining the three sub-dimensions of these symptoms indicated that one hour after exposure Nausea symptoms were 10x's higher, Oculomotor disturbances were 7x's higher and Disorientation was 95x's higher than pre-exposure levels. The very high levels of reported Disorientation are consistent with other studies that indicate that VE systems engender high levels of dizziness and vertigo upon post-exposure. The tangible and persistent aftereffects raise concerns for the safety and well being of VE system users and suggest that their activities should be monitored upon post exposure.
The Effects of Image Scale Factor on Vestibulo-Ocular Reflex Adaptation and Simulator Sickness in Head-Coupled Virtual Environments
Authors: Draper Mark H.
Published: January 2012

An experiment was conducted to determine the effects of virtual image scale factor on vestibulo-ocular reflex (VOR) adaptation and simulator sickness as a result of exposure to a head-coupled virtual interface. Subjects were exposed for 30 minutes, completing visual search tasks using active, unrestricted yaw head movement rotations. Three levels of image scale-factor changes (0.5X, 1.0X, 2.0X magnification) were explored. It was hypothesized that scale factors deviating from 1.0X magnification would cause VOR gain adaptation and increased simulator sickness. A secondary hypothesis predicted a moderate correlation between VOR gain adaptation and simulator sickness. Results demonstrated that significant VOR adaptation occurred only in the 0.5X and 2.0X scale conditions. VOR gain decreased an average of 15% in the 0.5X condition and increased an average of 6% in the 2.0X condition. Simulator sickness magnitudes in these two conditions were over twice that of the 1.0X condition. Only weak correlations were found between VOR gain adaptation and simulator sickness. Virtual interface design guidelines are suggested to minimize unwanted interface-generated effects on the user.
Effects of Age and Field-of-Viewon Spatial Learning in an Immersive Virtual Environment
Authors: McCreary Faith A. , Williges Robert C.
Published: January 2012

Adults and middle elementary schoolchildren (7-9 years old) were taught a route through a six room virtual house, while wearing a helmet mounted display (HMD) and using a joystick to navigate the virtual environment (VE). Participants viewed the environment under monoscopic conditions with field-of-view (FOV) set at either 30° H × 22° V or 48° H × 36° V. Participants performed tasks designed to assess their spatial knowledge in terms of landmark knowledge, route knowledge, and three configuration knowledge metrics. Landmark knowledge did not significantly change with age or FOV (p > .05). As both age and FOV increased, route and configuration knowledge significantly increased (p < .05). The results are discussed in terms of designing VEs for children.
The Effects of the Interface on Navigation in Virtual Environments
Authors: Peterson Barry , Wells Maxwell , Furness Thomas A. , Hunt Earl
Published: January 2012

Thirty participants explored two virtual mazes. Half of the participants used a hand-controller (joystick); the other half used the Virtual Motion Controller (VMC), a body-controller interface. Maneuvering performance, as measured by the precision with which subjects followed a marked route, was slightly better with the joystick. Route learning, as measured by the subjects' ability to replicate the route, was the same for both devices. Survey knowledge, or the ability to form a mental map of the space and to use it to find alternative routes was significantly better with the VMC. This enhancement in performance was conditional on maze difficulty. The more difficult the maze the greater was the performance benefit of using the VMC. The experiment provided evidence that an interface that uses the body may enhance certain components of navigation in virtual environments.
Virtual Environment Sickness: Adaptation to and Recovery from a Search Task
Authors: Singer Michael J. , Ehrlich Jennifer A. , Allen Robert C.
Published: January 2012

Virtual Environment technology provides a new way to simulate real world activities. Research conducted in our program and elsewhere indicates that VE sickness is common and may affect the use of VE (Lampton, et al., 1994; Wann, 1993). Kolasinski (1995) identified three categories of factors associated with simulator sickness: individual, task, or equipment (simulator) based. We employed the Simulator Sickness Questionnaire (Kennedy, et al., 1993) to investigate the progress of symptoms over an experiment. The task required searching through VE representations of complex building interiors for targets. The SSQ scores were not related to experimental condition nor was there a meaningful relationship with individual characteristics. Analyses found sickness: 1) increasing significantly from pre-VE exposure to mid-experiment measures, 2) significantly elevated at experiment end when compared to pre-experiment measures, and 3) not significantly different from the initial scores after a recovery period. These results indicate that a large proportion of the populace adapts to and recovers from VE successfully and within relatively short time frames.
Simulator Sickness and Related Findings in a Virtual Environment
Authors: Kolasinski Eugenia M. , Gilson Richard D.
Published: January 2012

Research indicates that users of Virtual Environments (VEs) can experience a variety of effects known as “simulator sickness.” A PC-based VE system was used to investigate sickness occurring in conjunction with a 20-minute exposure to the game Ascent. Forty undergraduates served as participants. Sickness was measured with the Simulator Sickness Questionnaire (SSQ). Data on gender, possible lingering/delayed effects, inter-pupillary distance (IPD), and final level reached in Ascent were also collected. Statistical comparison of the pre- and post-exposure SSQ data established sickness occurrence. The results indicated that sickness could be severe and may involve lingering and/or delayed effects. Gender differences in mean sickness scores were not statistically significant. A significant negative correlation was found between IPD and the SSQ Eyestrain symptom. Significant negative correlations were also found between sickness scores and final level reached in Ascent. These findings provide some insight into possible effects of VE exposure and suggest some areas for research.
Performance Errors in Virtual Work: Separating Display and Input Device Effects of a Virtual Environment Interface System
Authors: Eggleston Robert G. , Janson William P.
Published: January 2012

Psychomotor performance involves a closed-loop interaction of motor control and perception. A 3D virtual environment (VE) system inserts technology in both the motor side (input device) and perceptual side (viewing system) that will affect task performance. Often performance studies associated with VE systems will compare input devices or viewing systems without considering the affect of other components on performance. This may create a problem in the attribution of the absolute magnitude of effect that can be assigned to a single subsystem/device in a VE system. This paper presents a data analysis strategy and procedure to address the attribution problem. The procedure is described and illustrated with data from a comparative device study involving a 3D virtual environment system. Benefits and limitations of the strategy are discussed.
Testing the Tau Hypothesis against Alternative Information Sources used for Collision Avoidance
Authors: Stanard Terry , Smith Matthew R. H.
Published: January 2012

Research on the visual information used in collision avoidance has inappropriately attributed adequate task performance to the use of the visual variable tau (τ). We constructed a collision avoidance experiment where the τ hypothesis was tested against the use of other potential information sources, including expansion rate. Subjects viewed a head-on flight towards one or two barriers. During the first half of trials, a single barrier was present and subjects were instructed to approach it as closely as possible before ascending over it. During the second half of the trials, a second barrier was placed above the first and subjects flew through the resulting gap. The ascent dynamics were manipulated between subjects, such that a time-to-contact margin demarcated the collision boundary with one group, but a constant distance-to-contact margin with another group. Subjects in the time-relevant group responded in a manner more consistent with the use of expansion rate information, but neither a single critical expansion rate or τ strategy adequately explains performance in the two-barrier condition. Subjects in the distance-relevant group responded in a manner consistent with the use of relative distance information.
Human Factors Assessment of ISO 9241-7, “Requirements for Displays with Reflections.”
Authors: Kempic Joy , Olacsi Gary S. , Beaton Robert J.
Published: January 2012

This work evaluated the recently-published ISO 9241-7 “Ergonomic requirements for office work with visual display terminals (VDTs) - Part 7: Requirements for display with reflections” technical standard in terms of the readability of text passages presented on CRT displays. The effects of five illumination conditions and two screen contrast polarities on Tinker Reading Test scores (i.e., reading times and errors) were assessed for seven CRT/anti-reflection filter configurations. The readability scores were compared to ISO 9241-7 compliance classifications obtained for the seven CRT displays, as well as to two contrast metrics underlying the ISO 9241-7 compliance classifications: screen image luminance ratio and specular reflection luminance ratio. The findings show that only the specular reflection luminance ratio for large-area, negative polarity correlated with reading times. The present findings, along with those in a companion work (Olacsi, Kempic, and Beaton, 1998), contribute to the understanding of CRT viewability in glare environments and point out some shortcomings of ISO 9241-7. In particular, the findings indicate that specular reflections from CRTs degrade image quality more than do diffuse reflections, and, therefore, the importance of specular reflections is underemphasized in the ISO 9241-7 standard.
Human Factors Assessment of ISO 9241-7, “Requirements for Displays with Reflections”
Authors: Olacsi Gary S. , Kempic Joy , Beaton Robert J.
Published: January 2012

This work evaluated the recently-published ISO 9241-7 “Ergonomic requirements for office work with visual display terminals (VDTs) - Part 7: Requirements for display with reflections” technical standard in terms of perceived image quality judgments for CRT displays. The effects of five illumination conditions and two screen contrast polarities on image quality were assessed for seven CRT/anti-reflection filter configurations. Participants judged the image quality of the displays after reading text passages on the screen. Image quality judgments then were compared to ISO 9241-7 compliance classifications, as well as to two metrics inherent to the standard: screen image luminance ratio and specular reflection luminance ratio. The findings of this work (along with Kempic, Olacsi, and Beaton, 1998) contribute to a human factors justification of ISO 9241-7 and point up several shortcomings in this international standard. In particular, the findings indicate that specular reflections from CRTs degrade image quality more than do diffuse reflections, and, therefore, the importance of specular reflections is understated in the ISO 9241-7 standard.
The Virtual Retinal Display: A new Display Technology using Scanned Laser Light
Authors: Pryor Homer L. , Furness Thomas A. , Viirre Erik
Published: January 2012

The Virtual Retinal Display (VRD) is a new display technology that scans modulated low energy laser light directly onto the viewer's retina to create a perception of a virtual image. This approach provides an unprecedented way to stream photons to the receptors of the eye, affording higher resolution, increased luminance, and potentially a wider field-of-view than previously possible in head coupled displays. The VRD uses video signals from a graphics board or a video camera to modulate low power coherent light from red, green and blue photon sources such as gas lasers, laser diodes and/or light emitting diodes. The modulated light is then combined and piped through a single mode optical fiber. A mechanical resonant scanner and galvanometer mirror then scan the photon stream from the fiber in two dimensions through reflective elements and semitransparent combiner such that a raster of light is imaged on the retina. The pixels produced on the retina have no persistence, yet they create the perception of a brilliant full color, and flicker-free virtual image. Developmental models of the VRD have been shown to produce VGA and SVGA image quality. This paper describes the VRD technology, the advantages that it provides, and areas of human factors research ensuing from scanning light directly onto the retina. Future applications of the VRD are discussed along with new research findings regarding the use of the VRD for people with low vision
Sustained Attention and Feature-Integrative Displays
Authors: Miller Louis C. , Warm Joel S. , Dember William N. , Schumsky Donald A.
Published: January 2012

Observers monitored the repetitive presentation of a simulated submarine detection display for occasional targets. Observers were required to integrate information contained in one, two, or three indicators either in a simultaneous (comparative judgment) or successive (absolute judgment) format. Consistent with earlier findings on feature-integration, performance efficiency varied inversely with the number of features which needed to be integrated in signal detection. Unlike previous studies involving unitary discriminations, observers in the simultaneous conditions performed more poorly than those in the successive conditions as the information processing demands of the monitoring task increased. The results indicate that while systematic differences were found between simultaneous and successive task-types, different factors may play a role when observers must contend with multiple as compared to unitary sources of information.
Free Flight and the Air Traffic Controller: Active Control versus Passive Monitoring
Authors: Metzger Ulla , Parasuraman Raja
Published: January 2012

Free Flight, as originally proposed by the RTCA (1995), would allow transfer of authority for separation of aircraft from the air traffic controller to the pilot. More recent proposals have called for final authority to rest with the controller (FAA, 1997). These proposals have differing implications for the controller in terms of active control and passive monitoring. The present study investigated the effects of active control versus passive monitoring and traffic density on controller mental workload, performance, and memory in an air traffic control (ATC) task simulating FF conditions. Eighteen ATC specialists participated in an ATC simulation. Independent variables were (1) active control versus monitoring of traffic and (2) moderate versus high traffic density. Dependent variables included accuracy and timeliness in detecting potential conflicts, accepting and handing-off aircraft. Mental workload was assessed with a secondary task, heart rate variability and NASA-TLX ratings. Controller memory of aircraft positions was tested. Results showed detrimental effects of high traffic and passive control on performance. High traffic density increased mental workload. The detrimental effects of passive monitoring on controller performance validate the recent proposal to keep separation authority with the controller.
Alarm Related Incidents in Aviation: A Survey of the Aviation Safety Reporting System Database
Authors: Bliss James P. , Freeland Mary J. , Millard John C.
Published: January 2012

Today's aircraft cockpits are complex environments requiring pilots to monitor a large number of automated displays and alarm systems. A recent investigation of alarm-related incidents in Naval aircraft found high rates of alarm-related problems, particularly false and missed alarms. For the current research, we analyzed a sample of narrative accounts taken from the National Aeronautics and Space Administration's Aviation Safety Reporting System (ASRS). We categorized and tabulated the data according to alarm problem (false, missed, or other), aircraft type, avionics (alarm system), and flight phase. Our findings indicated that alarm-related incidents are still quite common in civil aircraft. Furthermore, most alarm-related incidents occur during the approach phase of a flight, and are likely to involve the Ground Proximity Warning System (GPWS) or the Traffic Collision Avoidance System (TCAS). We recommend further empirical research to understand alarm-related problems, particularly the cry-wolf effect.
Pilot Performance and Anxiety in a High-Risk Flight Test Environment
Authors: Hunn Bruce P. , Camacho Monica J.
Published: January 2012

Recent flight testing of an Automatic Ground Collision Avoidance System (AutoGCAS) provided the opportunity to test a variety of variables thought to influence pilot and aircraft performance under high-risk flight situations. Pilot anxiety ratings were compared to measures of elevation from the ground, airspeed, time-to-ground impact, bank angle, and heart rate during the accomplishment of dive recovery maneuvers. Pilot activation of an experimental AutoGCAS provided the chance to study pilot anxiety levels in situations not normally encountered during flight test. A multivariate statistical model was used to determine the contribution of each of the variables chosen on the outcome of flying a semi-automated aircraft control system under high-risk conditions. Results indicated that several flight variables with high face validity were not major contributors in terms of determining pilot performance, however a more complex model of interactive system effects may be indicated by this test.
The Use of Predictive Displays for Aiding Controller Situation Awareness
Authors: Endsley Mica , Sollenberger Randy , Stein Earl
Published: January 2012

This study provides an empirical evaluation of the effects of an enhanced predictive display concept for air traffic control. The predictive display informed the controller of the targeted altitude or heading of aircraft in a transitionary state The information provided simulated that which could be produced by a datalink from the aircraft's flight management system in a future air traffic system operation. The pilots in the simulation operated under self-separation rules and did not request clearances for altered flight plans. Use of the predictive display resulted in improvements in some air traffic control performance and situation awareness measures. Based on the results of the study, we recommend making improvements to the predictive display to better integrate it with the controller's radar display.
The Challenges of Long-Duration Spaceflight to Astronaut Safety, Performance, and Mission Success
Authors: Morphew M. Ephimia
Published: January 2012

The spaceflight environment is characterized by temperature extremes, microgravity, solar and galactic cosmic radiation, lack of atmospheric pressure, and high-speed micrometeorites. While these factors introduce a host of physiological, biomedical, and environmental stressors to flight crews, long-duration spaceflight has revealed an additional group of stressors that also impact flightcrew performance and behavior. Some believe that the most critical problems limiting long-duration spaceflight, after the biomedical, are the behavioral and performance (Atkov, 1996; Kozlovskaya, 1996). Flight safety and mission success depend on crew performance (Nechaev, Myasnikov, & Stepanova, 1996; Shields & King, 1998), as well as spacecraft system performance. Russian and American experience with long duration spaceflight has revealed that the stressors of long-duration spaceflight impact human performance more significantly than in short-duration flight (Jdanov, 1996; Kanas, 1985; Nichols, 1987). Accordingly, operation of the International Space Station (ISS) will necessitate greater resource allocation devoted towards understanding, developing, and applying effective performance, human factors, and psychologically-oriented countermeasures aimed at enhancing flight crew functioning. This paper is oriented towards providing human factors professionals with a high-level understanding of the stressors experienced by astronauts with long-duration spaceflight. For a more complete overview of the field of astronaut psychology and performance, see Whitmore and McQuilkin, 1998; Myasnikov and Zamaletdinov, 1996; Manzey, Schiewe, and Fassbender, 1995; Santy, 1994. The purpose is not to critique flight crews—as they are comprised of exceptional individuals who must deal with exceptional circumstances. As psychologists and human factors professionals, our purpose in illuminating these stressors and their effects is to apply our understanding of human performance and behavior to increase the overall safety, well-being, health, and performance of flight crews in preparation for ISS.
Space Human Factors Engineering Challenges in Long Duration Space Flight
Authors: Garland Daniel J. , Endsley Mica R. , Ellison June , Caldwell Barrett S. , Mount Frances E.
Published: January 2012

The focus of this panel is on identifying and discussing the critical human factors challenges facing long duration space flight. Living and working aboard the International Space Station (ISS) will build on the experience humans have had to date aboard the Shuttle and MIR. More extended missions, involving lunar and planetary missions to Mars are being planned. These missions will involve many human factors challenges regarding a number of issues on which more research is needed.
Expertise and Aging in Pilot Communication: The Role of Environmental Support
Authors: Morrow Daniel G. , Menard William E. , Stine-Morrow Elizabeth A. L.
Published: January 2012

We examined whether expertise reduced age differences on a pilot communication task. Young, middle-aged, and older pilots, and nonpilots of similar age and general cognitive ability, listened to recorded ATC messages that described a route through an airspace, while referring to a map of the airspace. They read back the ATC instructions (e.g., to change heading) and then answered a probe question about the aircraft's position. Morrow et al. (1999) used a similar procedure and did not find that expertise reduced age differences in readback accuracy. In the present study, participants were also allowed to take notes while listening to the messages. Contrary to the earlier study, pilots' readbacks were virtually perfect regardless of age, while readback accuracy declined with age for nonpilots. Note-taking may have provided environmental support that reduced working memory demands imposed by the communication task, which differentially benefitted older pilots. This suggests that cognitive aids such as note-taking is an important part of pilots' expertise.
Multiple-Task Performance: A Comparison of Younger and Older Adults
Authors: Sit Richard A. , Fisk Arthur D.
Published: January 2012

There is considerable disagreement among researchers regarding the psychological mechanisms underlying age-related acquisition and transfer of attentional control in multiple-task environments and effective training strategies. We outline a study conducted to examine the effects of extended practice on the performance of multiple tasks. In the study, five different training strategies (i.e., whole task, dual task, single task, embedded dual task, and embedded single task) were evaluated. The embedded dual- and single-task strategies required emphasis of a dual or single task within whole-task performance, respectively. The results revealed that both younger and older adults improved their multiple-task performance of a wide-ranging, complex set of tasks; however, younger adults consistently outperformed older adults. Except for single-task training, training strategy had little differential effect on younger adults' multiple-task performance. On the contrary, among older adults the most effective training strategies were the whole- and dual-task strategies, which required concurrent-task performance, self-assignment of task priorities, task coordination, and performance strategy development for two or more tasks. Single-task training, overall, was the least effective among the five training strategies. The theoretical and practical implications for these findings are disussed.