bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effectiveness of Various Attitude Indicator Display Sizes and Extended Horizon Lines on Attitude Maintenance in a Part-Task Simulation
Authors: Comstock J. Raymond , Jones Leslie C. , Pope Alan T.
Published: January 2012

Spatial disorientation (SD) is a constant contributing factor to the rate of fatal aviation accidents. SD occurs as a result of perceptual errors that can be attributed in part to the inefficient presentation of synthetic orientation cues via the attitude indicator when external visual conditions are poor. Improvements in the design of the attitude indicator may help to eliminate instrumentation as a factor in the onset of SD. The goal of the present study was to explore several display concepts that may contribute to an improved attitude display. Specifically, the effectiveness of various display sizes, some that are used in current and some that are anticipated in future attitude displays that may incorporate Synthetic Vision Systems (SVS) concepts, was assessed. In addition, a concept known as an extended horizon line or Malcolm Horizon (MH) was applied and evaluated. Paired with the MH, the novel concept of a fixed reference line representing the central horizontal plane of the aircraft was also tested. Subjects' performance on an attitude control task and secondary math workload task was measured across the various display sizes and conditions. The results, with regard to display size, confirmed the “bigger is better” concept, yielding better performance with the larger display sizes. A clear and significant improvement in attitude task performance was found with the addition of the extended horizon line. The extended or MH seemed to equalize attitude performance across display sizes, even for a central or foveal display as small as three inches in width.
Effects of Automation Reliability on Human Monitoring Performance
Authors: Oakley Brian , Mouloua Mustapha , Hancock Peter
Published: January 2012

Human decisions to rely on automation of a simulated flight task were monitored in the present study. Participants performed the Multi Attribute Task (MAT) battery previously developed by Comstock and Arneguard (1990). Twenty-eight participants were tested for 7 different reliability levels. Decision accuracy, false alarm rates, and reaction time to simulated automation failures were collected for each participant over nine 10-minute sessions. The results indicated that the rate of automation failures detected varied inversely with automation reliability level. As automation level increased, detection rate decreased thereby indicating automation-induced monitoring inefficiency. However, the mean reaction time of correct detection rate decreased as automation reliability level increased. No significant effect of reliability was obtained for the false alarm rate data. The implications for training and systems design are also outlined.
Maintenance-Related Accidents: A Comparison of Amateur-Built Aircraft to all Other General Aviation
Authors: Nelson Nicole L. , Goldman Scott M.
Published: January 2012

In a previous study, Goldman, Fiedler, and King (2002) found that a little over 7% of the 1983–1999 National Transportation Safety Board general aviation (GA) accident investigation reports listed at least one maintenance-related error as the primary cause or factor. Amateur-built aircraft accounted for an average of 14% of these same general aviation maintenance-related accidents, even though amateur-built aircraft account for less than 3% of the GA hours flown. Using the 1983–2001 National Transportation Safety Board GA accident investigation reports, this study compares maintenance-related accidents for amateur-built and all other GA aircraft by type of maintenance procedure, airframe hours, phase of operation, and time since last inspection. For this 18-year sample of maintenance-related accidents, 413 involved amateur-built aircraft, and 3,262 involved all other types of GA aircraft. General aviation flight hours continue to increase: Amateur-built aircraft flight hours, alone, increased from under 300,000 hours in 1993 to about 900,000 in 2000.
Situation Awareness Oriented Design: From User's Cognitive Requirements to Creating Effective Supporting Technologies
Authors: Endsley Mica R. , Bolstad Cheryl A. , Jones Debra G. , Riley Jennifer M.
Published: January 2012

Situation awareness is a fundamental construct driving human decision making in complex, dynamic environments. By creating designs that enhance an operator's awareness of what is happening in a given situation, decision making and performance can improve dramatically. The Situation Awareness-Oriented Design process provides a means to improve human decision-making and performance through optimizing situation awareness. This method has been used to develop and evaluate system design concepts in aviation, medical and information intelligence operations. It features three main components: SA Requirements Analysis, SA-Oriented Design Principles, and SA Measurement and Validation. This design process is user-centered, and derived from a detailed analysis of the goals, decisions and situation awareness requirements of the operator derived through a Cognitive Task Analysis methodology called Goal-Directed Task Analysis. The development of tool suites for supporting high levels of situation awareness in military command and control are presented to illustrate the use of the SA-Oriented Design process for translating the results of cognitive task analyses into to user-centered system designs.
Elicitation by Critiquing: An Exploratory Study
Authors: Miller Janet E. , Patterson Emily S. , Woods David D.
Published: January 2012

Knowledge elicitation methods uncover information about how a practitioner works in a field. However, these methods have the challenges of grounding in context, accessibility to experts and tasks, being laborious and time consuming, and repeatability. This study investigated a critiquing methodology's ability to address these challenges while still being authentic and generative. The domain investigated was military intelligence analysis, a field that experiences a constant turnover of workers. To maintain the highest level of productivity, the expertise of their military intelligence analysis practitioners must be understood. A study was done involving a novice performing a basic analysis task. Then, six experts with various backgrounds critiqued the novice's process. The results suggest that the critiquing method addresses the challenges of knowledge elicitation methods while being authentic and generative. The specific guiding question for addressing both issues was ‘Can the critiquing method be used to help unveil expertise in intelligence analysis?’
Using Psychologically Plausible Operator Cognitive Models to Enhance Operator Performance
Authors: Forsythe Chris , Bernard Michael , Xavier Patrick , Abbott Robert , Speed Ann , Brannon Nathan
Published: January 2012

Research by Sandia National Laboratories (SNL) is currently being conducted that seeks to embody human-like cognitive capacities in machines by transforming the human-machine interaction so that it more closely resembles a human-to-human interaction. This document reports on the initial phase of research and development by SNL in creating a capability whereby a machine-based cognitive model provides a real-time awareness of the cognitive state of an operator. In the capability referred to as “Discrepancy Detection,” the machine uses an operator's cognitive model to monitor its own state and when there is evidence of a discrepancy between the actual state of the machine and the operator's perceptions concerning the state of the machine, a discrepancy may be signaled. The current project offers successful evidence that a machine may accurately infer an operator's interpretation of situations based on an individualized cognitive model of the operator.
Looking Forward: A Simulation of Decision Aids in Tomorrow's Classroom
Authors: Beck Hall P. , Dzindolet Mary T. , Pierce Linda G. , Piatt Nancy
Published: January 2012

Although there are many examples of successful application, the introduction of decision aids into the home, school and workplace has frequently failed to produce expected gains. The present study sought to determine if undergraduates could effectively use a decision aid to improve their scores on a multiple-choice test. The design was a 2 (Aid Accuracy: 60%, 80%) × 3 (Trial Type: Aid Given On Request (OR), Aid Given On Every Trial (OET), No Aid Available). Results revealed a statistically significant Aid Accuracy × Trial Type interaction. Providing undergraduates with an aid that whose recommendations were correct on 60% of the trials did not enhance their test scores. However, equipping students with an was 80% accurate increased performance above the no aid condition. More molecular analyses yielded a series of results that further defined the effects of the decision aid on student performance. The most important of these was the discovery of a “mere presence” effect. Thirty 30 of 44 students requested no advice in the OR arrangement. With respect to information received, their OR trials were equivalent to the No Aid trials. Nevertheless, these students performed substantially better on the OR trials than on the No Aid trials. Thus, the decision aid had effects on performance that cannot be attributed to the information it supplied.
Effects of Age on Utilization and Perceived Reliability of an Automated Decision-Making aid for Luggage Screening
Authors: McCarley Jason S. , Wiegmann Doug A. , Wickens Christopher D. , Kramer Arthur F.
Published: January 2012

An experiment examined the effects of age on utilization and perceived reliability of an imperfectly reliable decision-making aid in a luggage x-ray screening task. Forty-five young adults and 45 elderly adults performed a simulated luggage screening task. Some subjects were provided the assistance of an automated decision aid with a hit rate of .90 and a false alarm rate of .25. Others performed the task with no aid. Signal-detection analysis revealed that automation improved sensitivity only for younger participants, suggesting a tendency for older participants to underutilize the aid's recommendations. Data also revealed unique patterns of individual differences in cue reliance among older and younger participants. Perceived reliability of the aid did not differ between age groups. Order of information presentation (with the aid's recommendation coming before or after the raw data) had little effect for either age group.
Measuring Shared and Team Situation Awareness in the Army's Future Objective Force
Authors: Bolstad Cheryl A. , Endsley Mica R.
Published: January 2012

A simulation exercise was conducted to assess the effectiveness of a new Army force structure called Objective Force. This paper will describe how shared and team situation awareness (SA) were measured and analyzed in this experiment with regards to how well the new force structure supports both SA at the individual officer level, within teams and across teams. Shared and Team SA were measured using the Situation Awareness Global Assessment Technique (SAGAT).
How Cognitive Artifacts Support Distributed Cognition in Acute Care
Authors: Nemeth Christopher
Published: January 2012

In acute health care, tightly constrained teams of service providers perform complex procedures that routinely have significant consequences. Recent patient safety research encourages the use of decision support tools to improve human performance. Multiple hospital departments collaborate in a distributed cognition to balance the demand for health care with resources such as care providers, equipment and facilities. To plan and manage the balance, an anesthesiologist and a nurse coordinator predict resource availability, build consensus among team members, resolve disputes, plan resource allocation, assess and re-plan the balance between need and resources, speculate about future needs, create trial solutions, anticipate resource requirements, bump procedures and stash and husband resources. The Availabilities Sheet, Master Schedule, Operating Room (OR) Graph and OR Board are four cognitive artifacts used to support their work. Artifacts must, at a minimum, be reliable, informative, efficient, clear, accurate, and malleable. Improvements to these and other information tools will benefit team work processes and thereby enhance patient safety. An example demonstrates how cognitive artifacts are used to support distributed cognition.
Barriers to Implementing Wrong Site Surgery Guidelines: A Cognitive Work Analysis
Authors: Rogers Michelle , Render Marta L. , Cook Richard I. , Bower Robert , Molloy Mark
Published: January 2012

In this paper, we explore the barriers wrong-site surgery guidelines face when applied in current work practice. Over 40 hours of direct observation of the entire care process (from initial consultation through post-operative care) were conducted. A breakdown in communication between surgical team members and the patient, operating room policy and procedures, incomplete patient assessment, staffing issues, distraction, and availability of pertinent information were identified by the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) in 1998. In response to the high visibility of wrong-sited surgeries, the American Academy of Orthopedic Surgeons (AAOS) among others, developed guidelines intended to reduce the risk but failed to account for the dynamic complex environment. Several process elements emerged from our analysis of observation and interview data as they affected the outpatient surgical process of identification. This paper suggests strategies to enhance resiliency already present in the system.
Using communication patterns in the design of an adaptive organizational structure for command and control
Authors: Graham John , Gonzalez Cleotilde , Doyle Michael
Published: January 2012

What type of analysis should be used to inform design when both the future organizational structure and the experimental simulation are tenuous? Neither the application of a qualitative process tracing method nor low-level quantitative organizational designs are warranted. We hypothesized the analyses of high-level communication patterns in a role-playing exercise of a future organization structure would yield results that could both inform organizational design and shape iterative experimental designs. This study summarizes the comparison between communication patterns in an envisioned organizational structure and the actual patterns of information exchange of experienced military participants role-playing staff members in a future organizational design. The comparison between the hypothesized and actual communication performance indicated a different distribution of communication interaction from the expected. These results help guide both the future organizational concept as well as next iteration experiments.
Use of Critical Analysis Method to Conduct a Cognitive Task Analysis of Intelligence Analysts
Authors: Hutchins Susan G. , Pirolli Peter , Card Stuart
Published: January 2012

Intelligence analysts (IAs) engage in information seeking, evaluation, prediction, and reporting behavior in an information-intensive work environment. A Cognitive Task Analysis (CTA) was conducted to capture data that will provide input to support development of a model of the IAs processes, biases, and analytic strategies. A hybrid method was used to conduct the CTA, including a modified version of the critical decision method — the critical analysis method. The essential distinction was that participants were asked to describe an example of a strategic analysis problem. Procedures used to conduct the critical analysis method are described in this paper. Several factors contribute to making the IA's task challenging: ( i) time pressure to produce reports in a shorter timeframe, ( ii) a high cognitive workload, and ( iii) difficult human judgments that are required regarding uncertain validity and reliability of the data. Human judgments are involved in considering the plausibility of information, deciding what information to trust, and determining how much weight to place on specific pieces of data. Intelligence analysis involves a complex process of assessing the reliability of information from a wide variety of sources and combining seemingly unrelated events. This problem is challenging because it involves aspects of data mining, data correlation and human judgment.
Usar: A Game Based Simulation for Teleoperation
Authors: Wang Jijun , Lewis Michael , Gennari Jeffrey
Published: January 2012

We are developing simulations of the National Institute of Standards and Technology (NIST) Reference Test Facility for Autonomous Mobile Robots (Urban Search and Rescue) in order to develop and test our strategies for Robots-Agents-People (RAP) team coordination and control. We have shortened the simulation development cycle to a mere two months by using a commercial game engine to provide high quality graphics and dynamics and taking advantage of the sophisticated development environments available for modern games. In this paper we present our architecture and approach for using engineering models, digital photographs, and physical measurements to rapidly produce game-engine based high fidelity teleoperation simulations.
The Effect of Display Modality on Decision-Making with Uncertainty
Authors: Basapur Santosh , Bisantz Ann M. , Kesavadas T.
Published: January 2012

This research compared visual (color), auditory (tone pitch), and tactile (vibration amplitude) displays of uncertainty in a threat avoidance task. Thirty participants used these displays to navigate through a simulated minefield, selecting paths that would minimize their chance of hitting a mine, while moving through the field as quickly and directly as possible. Results showed the participants in the visual condition to be the most conservative (safer but longer), while those in the auditory condition took the shortest (riskier) path. Interestingly, in terms of trial time, while all participants tended to improve their performance with respect to speed, participants in the tactile condition started out more slowly, but were similar in speed to the fastest, visual condition, by the end of the trials.
Supporting System-Centered View of Operators Through Ecological Interface Design: Two Experiments on Human-Centered Automation
Authors: Furukawa Hiroshi , Parasuraman Raja
Published: January 2012

Human operators faced with an unexpected situation while controlling a complex system can take effective action if they are provided a system-centered view based on Ecological Interface Design (EID). To date there is only limited empirical support for the efficacy of EID in enhancing human-automation interaction. This paper presents results from two studies of EID in human-automation interaction, drawn from different domains, flight simulation and process control. In Experiment 1, use of an integrated display with an emergent perceptual feature was found to eliminate the automation complacency effect in monitoring for engine system malfunctions during a flight simulation task. In Experiment 2, a display with a multi-level representation of the intention of the automated controllers in a process control system was found to improve human-automation collaboration. These studies show that explicit visualization of the functional structure of a human-automation system in the interface supports the system-centered view in operators, thereby enhancing system performance.
The Use of Cognitive Feedback by Experts and Novices in a Judgment Task
Authors: Ma Jiao , Kudrycki Keith
Published: January 2012

Cognitive feedback (CFB) has been shown to increase performance in Multiple Cue Probability Learning (MCPL) tasks in both real life and experimental situations. Our experiment focuses on investigating how experts and novices behave differently in applying CFB, which is presented in forms of relative importance weights of each of the cues and the display of function forms (Weaver and Steward, 2000). We believe this study provided some interesting insight into how much domain knowledge is necessary to understand and apply CFB. The study examined how well novices and experts are able to process and use different types of feedback (i.e. CFB and Outcome Feedback) and hence determined which type is more useful for novices or for those with prior knowledge of the task. A total of 20 participants, 10 experts and 10 novices, were given a series of baseball statistics and asked to predict how many wins the team would have in a season based on these statistics. Performance measures (e.g. relative weighting accuracy, Lens Model measures), mental workload and judgment strategy were measured. Domain Knowledge was statistically significant for all weights except one less important cue, “stolen bases.” In other words, domain knowledge impacts weighting accuracy greatly. Domain knowledge was also found to have a significant effect on judgment performance (i.e. Lens Model measures), such as accuracy and knowledge. Mental workload was significantly affected by CFB, but none of the other dependent variables were.
Naturalistic Observation of Airport Incident Command
Authors: DeJoode Janie A. , Cooke Nancy J. , Shope Steven M.
Published: January 2012

In this paper we provide a set of observations, recorded in the context of incident command operations at an airport mass casualty exercise, that emphasize the need for cognitive engineering in the design of socio-technical systems such as this one. Observations of inadequate communication resources, insufficient leadership, and malfunctioning equipment were made. These shortcomings appeared to hinder team decision making and team communication capabilities. Our observations also revealed potential areas for improvements in the operation of airport incident command systems.
Usability of Configuration Systems in Design by Customer Web Sites
Authors: Khalid Halimahtun M. , Oon Yin Bee
Published: January 2012

This paper presents the usability findings of designing a cell phone online using a prototype configuration system to support mass customization. Two configuration systems were compared, one with 2-dimensional graphics, and the other with 3D virtual prototypes. Usability is measured on the effectiveness of the system in supporting Design by Customer activity and enhancing user satisfaction. About sixty subjects participated in the experiment. A matched between-subjects design was used with half of the subjects assigned randomly to the 2D configuration system and the remaining half to the 3D system. Their behavior was recorded on video, and they completed a usability questionnaire at the end of the session. The ANOVA results on web site features showed that designing a cell phone online induces the same pleasure to subjects irrespective of the system type. But the user satisfaction results indicated that the 3D system is more satisfying than the 2D system, suggesting that the use of 3D virtual prototypes increases satisfaction as it represents the real world environment that enables users to view and visualize the product directly. A flexible design procedure is also critical in increasing user satisfaction.
A Comparison of Older vs. Newer Over-the-Counter (OTC) Nonprescription Drug Labels on Search Time Accuracy
Authors: Shaver Eric F. , Wogalter Michael S.
Published: January 2012

The present study evaluated response time and accuracy to answer a series of questions of information in 16 (8 older and 8 newer ‘Drug Facts’) over-the-counter (OTC) drug labels. The newer labels include aspects, based on previous research, which should benefit performance. The results indicated that participant's response times were significantly faster with the newer labels compared to the older ones. However, this was not true of all OTC product samples. Accuracy was high (error rate low) for both label formats. Response times for females were significantly faster than males for both label types. The benefits of formatting text for facilitating information acquisition from drug labels and other kinds of printed information are discussed.
Influences of Information and Personal Concerns on Monetary Judgments
Authors: Leonard S. David
Published: January 2012

Previous studies have shown effects of various types of suggestions made by attorneys for developing a metric for damages to be awarded for pain and suffering. This study attempted to use rates set by respondents for their willingness to endure some of the problems of a wheelchair-bound individual as a means of getting the respondents to devise suitable awards for pain and suffering. Experimental subjects were asked how much would be necessary before they would spend a day living in a wheel chair, and control subjects were not. Variability of responses was high for both willingness to accept the wheelchair temporarily and for awards for pain and suffering. Although those who presumably thought about the problem more suggested higher awards, the difference was not statistically reliable. Within the Experimental Group there was a dependably greater amount awarded by those who said they would require larger sums to accept such a situation. Those respondents who were asked to specifiy total amounts suggested dependably lower awards than those who responded in terms of daily amounts. Possible reasons for some to these effects are discussed.
The Usability of Iconic Designs a Case Study of Juicy Salif
Authors: Russo B. , De Moraes A.
Published: January 2012

This paper is the first part of a research project about the lack of usability in products with a strong aesthetic appeal. The hypothesis of this research is that products — Icons, influenced by marketing and admired by consumers for aesthetic priority, have a disabled usability because of the absence of ergonomics approach during the design phase. Here, a short history about the arise of industrial aesthetic and the relationship between product and beauty is presented, together with a study about product's pleasurability. A case study about the lemon squeezer JUICY SALIF, a design icon considered product, is also presented, through usability tests, questionnaires and comments suggested by admirers through an internet forum.
Development of a Qwerty-Type Reduced Keyboard System for Mobile Computing: Tengo
Authors: Tan Ken C.F. , Ng Edwin , Oh Julian J.S.
Published: January 2012

As mobile devices get smaller and more text applications are migrated to the mobile platform, there is an increasing demand for a text-inputting solution that is not only fast, easy and intuitive but also suitable for sustained or intensive text-inputting. Because of the space constraint and ever-shrinking form factor of mobile devices, we approached the problem using a reduced keyboard system to minimize the number of keys required. We also wanted to capture the ubiquitous QWERTY design into the reduced keyboard design to minimize re-learning and tap on existing memory mapping of keyboard layouts. The third and last design consideration was to shrink the number of keys to a minimum of 10, thus allowing each key to ultimately be able to uniquely match to each individual finger. The end objective was thus the development of a 10 key ambiguous text-inputting keyboard system that is designed for double-thumbed or double-handed typing (QWERTY characteristic).
Human and Computer-Generated Essay Grades
Authors: Boring Ronald Laurids
Published: January 2012

The advent of computerized essay grading brings with it significant questions about the interaction between the grader and the student. An experiment is presented that compares two forms of human essay grading with computerized essay grading. Twenty human graders using either holistic or analytic grading methods marked 15 student essays. These essays were subsequently marked by computer using a grading implementation of latent semantic analysis. There were significant correlations between both holistic and analytic graders and the computerized essay grader.
Effect of Providing Foot Support on Lower Leg Temperature for Sedentary Workers
Authors: Hedge Alan , Bhambore Meghna
Published: January 2012

Fourteen subjects sat for 20 minutes either with their legs dangling and unsupported, or supported on a flat surface. Foot and calf skin surface temperature measures were taken using infrared thermography. Laboratory climate conditions were recorded. Results showed a significant decrease in both foot and calfskin surface temperatures (∼0.7°C and 0.2°C respectively) when sitting with the feet supported compared to sitting with the legs dangling but stationary. Results suggest that although foot support may be important, if the supported legs are stationary this may increase venous stagnation. Strategies for periodically moving the supported feet should be considered.
Performance and Economic Benefits of Object Oriented Task Analysis with Cognitive Flow Diagrams
Authors: Steinberg Richard K. , Riss Robert
Published: January 2012

While there have been many advances in Human Computer Interaction design, modern user interface (UI) design often remains deficient in its ability to augment human performance. McInerney and Sobiesiak (1999) argue that many user interface deficiencies arise because the UI design process is “ad hoc” and is based on subjective design methods. To build a user interface for a Command and Control (C2) display, an Object Oriented Task Analysis (OOTA) process was used. This process was augmented by incorporating a Cognitive Task Analysis and generating a human Cognitive Flow Diagram (CFD). By applying this structured engineering process built around an OOTA and CFD, C2 displays are being “recreated” in a manner that improves human performance and reduces cost offering a 6 to 1 ratio on return of investment for human factors effort in the program. The process resulted in display designs that outperformed baseline designs 25–70%.
The Ergonomics of Torture: The Moral Dimension of Evolving Human-Machine Technology
Authors: Hancock P.A.
Published: January 2012

No intelligent human activity is devoid of purpose. This is as true for science as for any other pursuit. The abdication of science from the realm of purpose — the propositional divorce of ‘what is’ from ‘what should be’ is a widely-perpetuated but fatal fallacy. As much as purpose predicates process, process promotes purpose. Purpose and process are locked in a symbiotic circle in which their independent existence is essentially meaningless. Unlike those who simply study the world as it is, we in human factors, as agents of change, must contemplate the world as it can be, in both its proximate and more distal forms. In seeking to change the world, as opposed to merely studying it, we cannot avoid the moral dimension of action. Here I examine our nascent approach to such issues using a pointed exemplar to trigger both visceral and cerebral response. The work is part of a continuing effort to found a new philosophy based upon perception-action mediated through our technological extensions to all human capacities.
Sage: Five Powerful Ideas for Studying and Transforming the Intelligence Analyst's Task Environment
Authors: Gray Wayne D. , Schoelles Michael J. , Bringsjord Selmer , Burrows Kirk , Colder Brian
Published: January 2012

Sage provides a scaled world in which real and simulated intelligence analysts work to solve realistic scenarios in innovative task environments. All aspects of Sage are instrumented for data collection and Sage itself is built to facilitate the swapping in and out of prototypes of innovative tools for information search, hypothesis generation, and hypothesis testing. Sage focuses not simply on the promised functionality of these tools, but the way in which the design of the interface supports or hinders the realization of this functionality. Beyond the individual tool and its interface, Sage supports the cognitive engineering of integrated task environments by the use of simulated cyborgs (simBorgs). SimBorgs combine high-fidelity computational cognitive models with low-fidelity artificial intelligence (AI) based reasoning components. This combination of cognitive modeling with AI enables the creation of intelligent agents, simBorgs, that will work tirelessly to perform usability testing on various combinations of tasks and interfaces.
The Effects of Age on Stress and the Biomechanics of Slips and Falls
Authors: Davis Thomas W. , Lockhart Thurman E.
Published: January 2012

A study was conducted to investigate if stress associated with a fear of falling contributes to the increased incidents of falls among older adults. The investigation compared physiological stress, with biomechanical parameters of walking for twenty-eight participants in two age groups: (18–35) and (65 or older). Both age groups were evaluated while walking over dry and slippery floor surfaces. Biomechanical parameters included: step length, required coefficient of friction (RCOF), slip distance, and heel contact velocity. Overall, the results indicated that there were differences between older and younger adult's biomechanical parameters of walking, and their physiological stress associated with an inadvertent slip. Younger adult's normal RCOF was higher and their normal step length was longer compared to older adults. Older adult's stress level after a slip was significantly higher than younger adults. Furthermore, younger and older adults modified their step length differently to avoid slipping, when walking over the slippery floor surface. It was concluded that for the participants in this study some anxiety and stress might be beneficial in reducing the occurrence of inadvertent slips and falls due to an increased awareness of their external environment.
Is Chaos Present in Static Postures Observed at Work: A Nonlinear Dynamics-Based Analysis of Surface EMG Signals
Authors: Karwowski Waldemar , Rodrick David
Published: January 2012

The primary objective of the study was to explore the nonlinear characteristics of surface electrical activity of the biceps muscle during two (job safety critical) static postures observed on the assembly line. The results showed that for each trial in both postures (posture 1: the MVC condition, and posture 2: the no-loading test posture) the positive Lyapunov exponents exist. However, the statistical test of significance showed that surface EMG of the biceps brachii was more chaotic under the maximum loading in simulated posture 1 than under the no-loading condition in simulated posture 2. At the same time it was observed that the recorded two types of time series (EMG data) were almost equally complex, indicating the same source of the data. The existence of chaos in the EMG measure of muscle activity may indicate that conventional analysis could bear little meaning in explaining muscular fatigue.
Trunk Muscle Coactivation in Isometric Exertion Tasks
Authors: Song Young W. , Na Sukhee , Chung Min K. , Lee In S.
Published: January 2012

Antagonist coactivation levels of trunk muscles were determined quantitatively using three coactivation measures: the sum of antagonist NEMG, the sum of antagonist force, and the sum of antagonist moment. Twelve male subjects performed isometric voluntary exertions gradually increasing to maximum efforts in six directions: flexion/extension, left/right lateral bending, and clockwise/counter-clockwise twisting. Coactivation levels were assessed at 10, 20, 30, 40, 50, 60, 70, 80, and 90% MVE in six directions. Antagonist coactivation was dependent on the magnitude and direction of the exertion moment, while it showed different patterns according to the coactivation measures. Twisting moments induced highest coactivation in all three measures.
Working Upstream: Successes in Reducing Injury Risks in Construction
Authors: Spielholz Peregrin , Carcamo Ernesto , Davis Gary
Published: January 2012

An engineering solution to remove an injury risk factor is the preferred route for preventing musculoskeletal injuries when feasible. Construction has presented a challenge that is only recently being aided by new tool designs and work in the area. However, many risks are introduced or exacerbated by factors “out of their control”. Several projects in Washington State have investigated the benefits of working with manufacturers and architects to reduce the level of risk before the construction phase by repackaging materials or considering alternative designs with worker health and safety taken into account. To reduce lifting risks, composition shingles were successfully repackaged in lighter bundles weighing 48–50 lbs (previously 64 lbs) in cooperation with a large manufacturer. This intervention is presented as an example of working upstream to reduce injury risks.
Short-term Changes in Upper Extremity Dynamic Mechanical Properties Associated with Power Hand Tool Use
Authors: Radwin R. G. , Sesto M. E. , Richard T. G.
Published: January 2012

This study investigated the relationship between repetitive eccentric exertions in power hand tool operation and upper limb mechanical properties including stiffness and inertial mass, and physiologic measures including localized pain, discomfort, and swelling. Tool parameters, including peak torque (3 Nm and 9 Nm) and torque build up time (50 ms and 250 ms), were controlled in a full-factorial design. Twenty-nine participants were randomly assigned to one of the four conditions and operated a pistol grip nutrunner four times per minute for one hour in the laboratory. An average decrease in stiffness (48%) and mass moment of inertia (60%) of the upper limb was observed immediately following pistol grip nutrunner operation. A previously developed dynamic tool operator model was used to predict resulting handle force and displacement, and the conditions associated with the greatest handle force and displacement demonstrated the greatest decrease in mechanical stiffness and inertial mass, and the greatest increase in localized discomfort.
A Macroergonomic Approach to the Evaluation of Turnover among IT Workers
Authors: Schwarz Jen , Carayon Pascale , Hoonakker Peter
Published: January 2012

In this study, we examine turnover intention in Information Technology (IT) workers, in particular among women and minorities. An initial set of intention to turnover questions from the Michigan Organizational Assessment Scale (Seashore, Lawler, Mirvis, & Cammann, 1982) was used. Phone interviews were conducted with 13 people from three IT companies to refine these turnover intention questions. A new set of three questions was then developed to capture the causes and consequences of turnover intention. Data from 125 IT workers using this new set of questions is also reported.
Human Factors in Healthcare: Combining Quantitative and Qualitative Analysis
Authors: Wolf Laurie , Marshall Jessica , Sledge Jennifer A. , Potter Pat , Boxerman Stuart , Grayson Deborah , Evanoff Brad
Published: January 2012

The increasing physical, emotional and cognitive demands placed on nurses and other health care workers, coupled with higher patient acuity levels in the healthcare settings, have increased the risks of employee work stress and potential errors. Large-scale re-engineering efforts to contain costs through staff reduction and streamlining of processes over the past two decades have contributed seemingly to increased job stress of healthcare workers. Traditional human factors engineering methods used to evaluate activities yield a linear listing of activities, time, and motions involved in the patient care process. However, this approach does not provide an understanding of the cognitive work of clinical decision-making. Without this understanding, it is impossible to make judgements on “value added” or wasted motions, and errors. Traditional Human Factors methodology can be enhanced by adding qualitative observation of the nursing care process. The combined methodology provides detailed documentation of environmental conditions, sources of interruptions, and cognitive demands which may contribute to medical errors and compromised quality of care.
Increasing Intraoperative Patient Safety: Monitoring Drug Concentrations
Authors: Drews Frank A. , Syroid Noah D. , Agutter Jim , Albert Rob , Westenskow Dwayne R. , Strayer David L.
Published: January 2012

Monitors that show intravenous drug and effect concentrations currently do not exist. However, using real-time displays of intravenous anesthetic concentrations and effects could significantly enhance intraoperative clinical decision-making and patient safety. Pharmacological models are available to estimate drug concentrations in the brain, and to predict the drug's associated physiological effects. An interdisciplinary research team developed a graphic display incorporating these models to show the predicted present and future concentrations and effects of anesthetic drugs in real-time. The results of this study show that anesthesiologists using the display controlled hemodynamic patient variables better than a control group. Additionally, when using the drug display the procedure was shorter than in the control group. Taken together, the availability of a drug display has the potential to increase patient safety significantly.
Differences in the Use of Bar Code Medication Administration (BCMA) in Acute Care and Long-Term Care Settings
Authors: Patterson Emily S. , Chapman Roger J. , Rogers Michelle L. , Render Marta L.
Published: January 2012

In this paper, we explore how the use of a software package, Bar Code Medication Administration (BCMA), differs in acute care and long-term care settings. Direct observation of BCMA use during medication administration was conducted on acute care (42 hours) and long-term care (37 hours) wards in a small, medium, and large hospital. The following differences were found for all three hospitals: 1) acute care ward nurses used more detailed printed reports to plan medication passes and detect errors in ordering and dispensing than on the long-term care wards, 2) barcoded wristbands were scanned more frequently to identify patients on acute care than long-term care wards (53% vs. 8%), and 3) nurses administered medications immediately after scanning and opening medication packets more frequently on acute care than long-term care wards (93% vs. 23%). The findings highlight the need to tailor the BCMA software for the long-term care setting in order to improve patient safety.
Preliminary Evaluation of Electric Scooter Related Problems in Continuing Care Retirement Communities (CCRC)
Authors: Hart Traci A. , Sifrit Kathy J. , Chaparro Alex , Stumpfhauser Laszlo
Published: January 2012

Electric Scooters are assistive devices that have been well received by the older adult population (65 years and older). The increase in usage of these scooters is causing a number of problems for Continuing Care Retirement Communities (CCRC) that allow residents to operate them within their facilities. Due to a lack of literature addressing the use of electric scooters, interviews were conducted with three Kansas CCRC s and secondary data sources were analyzed to begin identifying the problems associated with the use of electric scooters. A number of important issues surrounding the use of scooters in CCRC facilities were identified including: 1) an apparent discrepancy between the problems identified in government databases and those reported by staff at CCRC facilities, 2) limited or non-existent driver training and education, 3) the misuse of scooters by drivers, and 4) an incompatibility between the scooters design and the target population.
Instrument Ergonomics Treatment ND Prevention of Injury in the Musician
Authors: Boyette Jennifer
Published: January 2012

Instrument ergonomics is the study of the interaction between a musician, body positioning, and the physical requirement of classic instrument design. The instrument tolerates minimal design changes because of an unyielding mechanical structure that has developed over centuries. Additionally, the musicians' performance technique allows few alterations to the delicate style of movement learned throughout a lifetime of study. The resultant challenge of instrument ergonomics is addressed by physicians and therapists who specialize in the physical problems of performing artists.
Detection of Changes in Tactical Displays: A Comparison of Two Symbol Sets
Authors: Keillor Jocelyn , Thompson Laura K. , Smallman Harvey S. , Cowen Michael B.
Published: January 2012

A major design issue for military tactical displays concerns how to make as much information as possible available to the user “at a glance”, without compromising the ability of the user to decompose the display into meaningful units or chunks. The choice of symbology may therefore be a critical factor in managing the complexity of tactical displays. A new method for evaluating symbol sets was developed, using a flicker paradigm to simulate an operator's shifts of attention during interaction with the display and environment. Two symbol sets were compared: MIL-STD-2525B, and Symbicons, a hybrid symbology recently developed by the U.S. Navy. Overall, Symbicons outperformed the traditional MIL-STD-2525B symbols when participants were required to detect heading changes. Furthermore, only the Symbicons allowed participants to take advantage of advance knowledge of the platform type (sea or air) in which they could expect a heading change.
Cerebral Vascularity and Performance on an Abbreviated Vigilance Task
Authors: Hollander Todd D. , Helton William S. , Tripp Lloyd D. , Parsons Kelley , Warm Joel S. , Matthews Gerald , Dember William N. , Parasuraman Raja
Published: January 2012

Transcranial Doppler sonography (TCD) and transcranial cerebral oximetry (TCCO) measures of blood flow and oxygenization levels in the brain were collected while observers performed an abbreviated 12 min vigilance task designed by Temple et al. (2000) to serve as an analog to more traditional long-duration vigils. Both measures showed higher levels of cerebral vascular activity in the right as compared to the left cerebral hemisphere indicating that the overall level of performance in the abbreviated vigil is right-lateralized, a finding that coincides with the outcome of earlier blood flow studies featuring more traditional long-duration vigils. This parallel provides strong support for Temple et al's (2000) argument that the abbreviated vigil is a valid analog of more traditional long-duration vigilance tasks and implies that laterality in vigilance is a generalized effect in terms of cerebral vascular dynamics that appears in terms of both blood oxygenation and hemovelocity.
An Investigation of Extreme Alarm Response Patterns in Laboratory Experiments
Authors: Bliss James P.
Published: January 2012

Response patterns to unreliable alarm systems often conform to probability matching theory. However, some participants have been observed to respond to all or no alarms in a given set. In this paper, we analyze extreme response patterns within seven alarm mistrust experiments. In half of those experiments, participants had no redundant cues regarding individual alarm validity, and relied only on an estimate of overall alarm system reliability. In the other half, participants knew overall system reliability and could check individual alarm validity. Results show that participants without alarm validity information were more likely to respond to all alarms. Those who could check individual alarm validity matched the true alarm rate with their responses. Our results confirm the importance of designing information redundancy within alarm systems. Practical implications include providing underlying system information to operators to ensure appropriate response patterns. Further research should be conducted to investigate lack of responding for low alarm system reliability rates.