bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Training Efficiency and Usability for a Graphical Flight Planning (GFP) System and a Conventional Multifunction Control Display Unit (MCDU)
Authors: Feigh Karen , Rogers William , Burke Kelly
Published: January 2012

A comparative study of a GFP input method and an MCDU for FMS-based flight planning was conducted to assess the impact of the input method on training and usability. Additionally, the effect of English language proficiency was also assessed. The GFP and MCDU systems were compared using 16 ab initio pilots with two levels of English proficiency. No significant differences were found for the majority of objective training measures analyzed, but there was a marginally significant advantage for the GFP system in terms of number of clearances successfully input within a specified time limit. Other significant differences in objective measures showed some advantages for GFP and some advantages for MCDU. The GFP had significantly better performance and significantly lower subjective rating of overall workload, ratings of effort and frustration. Overall the pilots perceived the GFP interface to be more intuitive, easier to use and faster to learn than the conventional FMS. Only minor differences were associated with English proficiency.
Measurement of Temporal Awareness in Air Traffic Control
Authors: Rantanen Esa M.
Published: January 2012

Temporal awareness, or level 3 situation awareness, is critical to successful control of air traffic, yet the construct remains ill-defined and difficult to measure. This research sought evidence for air traffic controllers' awareness of temporal characteristics of their tasks in data from a high-fidelity system evaluation simulation. Five teams of controllers worked on four scenarios with different traffic load. Several temporal parameters were defined for each task controllers performed during a simulation run and their actions on the tasks were timed relative to them. Controllers showed a strong tendency to prioritize tasks according to a first come, first served principle. This trend persisted as task load increased. Also evident was awareness of the urgency of tasks, as tasks with impending closing of a window of opportunity were performed before tasks that had longer time available before closing of the window.
Designing Memory Aids to Facilitate Intentions to Deviate from Routine in an Air Traffic Control Simulation
Authors: Loft Shayne , Smith Rebekah E. , Bhaskara Adella
Published: January 2012

In many occupations individuals need to remember to deviate from routine in order to perform intended actions, and a failure to do so can be catastrophic. The effectiveness of two memory aids was examined in an air traffic control simulation. After training on the air traffic control simulation, participants were instructed to press an alternative response key instead of a routine response key when accepting target aircraft into their sector. One type of memory aid presented this instruction constantly on the display screen. Despite this, individuals failed to deviate from routine just as often as when no such memory aid were available. A second memory aid was designed to pulsate (flash) at the time deviation from routine was required. This memory aid improved prospective memory performance. Implications for the design of memory aids for occupations where individuals monitor dynamic multi-item display screens are discussed.
Display type effects in military operational tasks using UAV video images
Authors: Minkov Yaniv , Oron-Gilad Tal
Published: January 2012

Employing advanced technology in combat can be helpful, but should be done with caution. Specifically, the use of video images retrieved from unmanned aerial vehicles (UAVs) by dismounted soldiers can be beneficial for presenting tactical and geographic information, when properly displayed. This work follows our previous studies on the type (e.g. size) of displays required by dismounted soldiers to process video feed from UAVs. Sixteen former infantry soldiers with no experience using UAV video feed participated. Four displays were examined in two scenarios (urban and rural) and in three different task domains (interpretation, orientation and response). Performance and subjective data were collected. Results show trends for differences between displays, scenarios, and task domain dependency. The most consistent trend marks the smallest display (personal digital assistant - PDA) to be unsuitable for this type of tasks.
False alerts in the ATC conflict alert system: Is there a “cry wolf” effect?
Authors: Wickens Christopher D. , Hutchins Shaun , Rice Stephen , Keller David , Hughes Jamie
Published: January 2012

We analyzed the extent to which a high false alert rate of the conflict alerting (CA) system in five ATC facilities was the cause of a “cry-wolf” effect, whereby true alerts of a pending loss of separation were associated with either controller failure to respond, or a delayed response. Radar track data surrounding 497 CA's were examined and from these we extracted information as to whether the alert was true or false, whether a trajectory change was (response) or was not (non-response) evident, whether a loss of separation occurred, and the controller response time to the CA. Results revealed an overall 47% false alert rate, but that increases in this rate across facilities was not associated with more non-responses or delayed responses to true alerts, or loss-of-separation. Cry-wolf appeared to be absent. Instead, desirable anticipatory behavior indicated that controllers often responded prior to the conflict alerts.
The Role of Human Factors in Older Worker Retention: What do we Know and what will we Need to Know?
Authors: Bruce Carrie , Gibson Sheree , Sanford Jon , Schwerha Diana , Spokus Diane , Whiting Harry S. , McLaughlin Anne , Shehab Randa L.
Published: January 2012

In less than two years the oldest of the baby boom cohort will begin to turn 65 and the projected mass exodus of the older workforce will begin—or will it? With the recent change in the economy and loss of trillions of dollars in retirement savings, many older workers will most likely need to work slightly longer than expected. Additionally, companies will be in need of retaining their most experienced employees or they will need to recruit experienced workers from other places. The goal of this discussion panel is to provide the latest data on ways we can utilize human factors and ergonomics interventions to retain older workers. Panel discussants are divided between industry and academia, and they will address: 1) issues related to common injuries of the older worker and ways to reduce them, 2) work factors significant to the retention of older workers, and 3) retaining older workers who have disabilities.
Cognition and Illness Experience are Associated with Illness Knowledge among Older Adults with Hypertension
Authors: Chin Jessie , D'Andrea Laura , Morrow Dan , Stine-Morrow Elizabeth A. L. , Conner-Garcia Thembi , Graumlich James , Murray Michael
Published: January 2012

We investigated how cognitive abilities and illness experience relate to illness knowledge. One hundred and forty-eight community-dwelling older adults including hypertensive patients and healthy adults completed a battery that measured illness knowledge, fluid cognitive abilities, crystallized abilities, and health history. Results suggested that hypertension knowledge was primarily associated with illness duration (despite a negative relationship between illness duration and fluid ability) and crystallized ability. Also, greater illness knowledge was associated with an illness perception that may be more consistent with self-care (e.g., greater sense of control). Implications for patient education and training are discussed.
Older Adults and Internet Health Information Seeking
Authors: Czaja Sara J. , Sharit Joseph , Nair Sankaran N. , Lee Chin Chin
Published: January 2012

The Internet is increasingly being used by consumers as a source of health information. This study examined factors that influence trust of Internet health information and how trust varies as a function of demographic characteristics, Internet experience, and computer attitudes. Data is also reported on the perceptions of the value and use of Internet-based health information. One hundred and twelve adults (50–85 years) were asked to perform Internet-based health information-seeking tasks and rate factors that influence their trust in Internet health information, the value of this information, and general trust of Internet information vs. trust of information from a doctor. The results indicated that trust is influenced by website identifiers (e.g., government agencies) and design features (e.g., ease of use). Most participants indicated that they would use the Internet health information and that access to this information would have some influence on their health behaviors. These findings underscore the importance of considering design and content issues when designing health websites.
Evaluating Emergency Department Information Technology Using a Simulation-based Approach
Authors: Pennathur Priyadarshini R. , Cao Dapeng , Sui Zheng , Bisantz Ann M. , Lin Li , Fairbanks Rollin J. , Guarrera Theresa K. , Brown Jennifer L. , Perry Shawna J. , Wears Robert L.
Published: January 2012

Manual status boards, which are used in many emergency departments to track patient and ED status information, are being replaced with electronic patient tracking systems. Such technology transitions can be challenging for the users and can produce undesirable consequences if the new technologies are not properly designed and tested. Understanding the impact of technologies such as electronic patient tracking systems before implementation in a real ED can help avert adverse safety consequences and promote user adoption. However, it is challenging to test technologies in real-world domains such as an ED, due to time pressures and safety critical tasks. A more feasible alternative is to employ simulation in a lab-based environment. This paper describes research measuring situation awareness and workload during user interaction with a simulated electronic patient tracking system. The impact of technology design on situation awareness and workload, and insights on design improvement are discussed.
Conscious versus Unconscious Processing in Dynamic Decision Making Tasks
Authors: Güss C. Dominik , Evans Jarrett , Murray Devon , Schaub Harald
Published: January 2012

Recent research suggests that unconscious processing is superior to conscious processing in tasks involving many decision alternatives (Dijksterhuis et al., 2006). One explanation for these findings is the limited information processing capacity of the human working memory and the almost unlimited resources of unconscious processing. The current study further investigates this topic by using more complex tasks than previously used, i.e., two complex, dynamic, and transparent tasks. Contrary to previous findings, instructions for conscious processing led to better performance in the more complex task. Results are explained referring to methodological reasons and to literature on metacognition. Besides the theoretical relevance, findings could be relevant for training programs on dynamic decision making.
Expert Judgment in a Heterogeneous Task Environment
Authors: Tsai Jennifer , Kirlik Alex
Published: January 2012

Recent times have seen an explosion of research on the intersection between rules, models, heuristics, and ecological task structure. Many groups have worked to connect loose strategies and findings into a more cohesive theory of judgment, specifying the particular ecologies under which various strategies work well or not. However, the majority of this research has been conducted under the assumption that judgment environments are homogeneous in composition. This paper reports an experiment in which the judgment task of interest possesses a heterogeneous structure, with different subsets of the task environment governed by different rules or weighting functions. Results reveal that experts were able to perform the task well by taking advantage of the heterogeneous nature of the task ecology, selectively choosing and adapting their use of strategies according to how well each operates in the different sub-ecologies of the task environment. Implications for understanding and supporting expert judgment in operational contexts are discussed.
Tactical Decision Making under Conditions of Uncertainty: An Empirical Study
Authors: Shattuck Lawrence G. , Miller Nita Lewis , Kemmerer Kacey E.
Published: January 2012

Uncertainty is a fundamental characteristic of warfare. Military decision makers confront uncertainty when the data they encounter are incomplete (missing), ambiguous, or conflicting. This study examined how different categories of uncertainty (ambiguous/missing, conflicting, baseline) affect response time and type of decisions made in a low-fidelity tactical decision making task. Prior to the study, researchers elicited real-world tactical scenarios from veterans of Operation Enduring Freedom and Operation Iraqi Freedom in which uncertainty was present. Nine scenarios were developed from the interviews and were given to 28 participants at the Command and General Staff College, FT Leavenworth, KS. Participants were asked to make a decision; their responses were recorded and analyzed. The results indicate that the category of uncertainty and scenario difficulty were significant factors in response time and type of decision made. These findings have the potential to improve human behavior modeling, tactical simulations, and representations of complex task environments.
Faith versus Trust: The Influence of Situational Experience on Perceived Signal Credibility, and a Distinction between Constructs
Authors: Bliss James P.
Published: January 2012

In this paper, operators' cognitive appraisal of sensor-based alarm systems is examined. To date, researchers have followed an inductive approach to alarm reactions, proposing trust-based theories to account for variability in alarm reactions. Deductive reasoning has likewise led researchers to collect data in support of various theories. Existing theoretical frameworks assume a common precursor to operator belief systems: firsthand experience with alarm systems. However, humans are frequently exposed to signals with which they have limited knowledge. The construct of alarm “faith” is proposed to account for initial differences in alarm responding prior to experience. Implications of the constructual distinction between faith and trust are discussed with consideration given to task training applications.
Cue validity, availability, and strategies: Finding experts in networked teams using the Team Map tool
Authors: Beer R. Dirk , Smallman Harvey S. , Lacson Frank C.
Published: January 2012

Team members in rapidly assembled and often spatially distributed command and control teams have little time to get to know each other. Yet they need access to each other's expertise to work effectively. Current tools such as organizational charts are inadequate because they do not provide sufficient cues to indicate who has what expertise. The Team Map tool is a “souped-up” organizational chart in the form of a table that can reveal information such as previous jobs, training or other attributes in an easy-to-use way. As the first step in its design, we investigate how much information can usefully be shown in the Team Map user interface, given several possible team organization types. Using a theoretical framework of cues and cue foraging strategies, we find that a Team Map with just one additional “summary” cue leads to robust expert-finding performance across organization types, regardless of validity of already available cues. Computer simulations of the foraging task showed participants used less of the information available in the user interface the more cues are provided, and that participants had relatively simple cue-use strategies.
The Effects of Automation Expertise and System Confidence on Trust Behaviors
Authors: Spain Randall D. , Bliss James P.
Published: January 2012

Trust in automation is more likely to be appropriate when information about the automation's capability is available. The goal of this study was to determine how automation expertise and system confidence affected automation trust behaviors. Forty-one participants completed a target detection task while receiving advice from an imperfect diagnostic aid that varied in expertise (expert vs. novice) and confidence (75% vs. 50% vs. 25%, no aid). Results showed that participants were more willing to comply with the highly confident expert aid than the highly confident novice aid. Furthermore, participants were more apt to generate false alarms as system confidence increased. These results suggest that, similar to interpersonal relationships, humans appraise automation features such as confidence and expertise when deciding to comply with automation. Implications and direction for future research are discussed.
Scaling Effects for Synchronous vs. Asynchronous Video in Multi-robot Search
Authors: Wang Huadong , Lewis Michael , Chien Shih-Hsiang , Velagapudi Prasanna
Published: January 2012

Camera guided teleoperation has long been the preferred mode for controlling remote robots with other modes such as asynchronous control only used when unavoidable. Because controlling multiple robots places additional demands on the operator we hypothesized that removing the forced pace for reviewing camera video might reduce workload and improve performance. In an earlier experiment participants operated four teams performing a simulated urban search and rescue (USAR) task using a conventional streaming video plus map interface or an experimental interface without streaming video but with the ability to store panoramic images on the map to be viewed at leisure. Search performance was somewhat better using the conventional interface; however, ancillary measures suggested that the asynchronous interface succeeded in reducing temporal demands for switching between robots. This raised the possibility that the asynchronous interface might perform better if teams were larger. In this experiment we evaluate the usefulness of asynchronous video for teams of 4, 8, or 12 robots. As in our earlier study we found a slight advantage in accuracy in marking victim locations for streaming video but overall performance was very similar.
Recovering from Interruptions: Does Alert Type Matter?
Authors: Andrews Alyssa , Ratwani Raj , Trafton Greg
Published: January 2012

One method for reducing the disruptiveness of interruptions is to present an alert prior to an interruption. Based on the Memory for Goals theory (Altmann and Trafton, 2002), this alert period provides an opportunity to maintain an associative link between the suspended primary task goal and relevant environmental cues which facilitates resumption. This theory does not, however, describe what types of alerts are most effective. Using reaction time and eye movement measures, three different types of alerts were examined to determine which alerts were the most effective and to determine which afforded the greatest opportunity to form an associative link between the suspended primary task goal and relevant environmental cues. Alert conditions resulted in faster resumption times than a no alert condition. There were no differences between the alert conditions themselves, despite eye movement differences reflecting cue association processes. The eye movement data suggest that one fixation is enough to form an associative link which reduces the disruptiveness of interruptions.
Use of Image-based Mnemonic Techniques to Enhance the Memorability of User-generated Passwords
Authors: Nelson Deborah L. , Vu Kim-Phuong L.
Published: January 2012

Participants in this study were assigned to one of three different password generation groups: image-based mnemonic, text-based mnemonic, or proactive password checking restrictions alone; and asked to generate and later recall passwords for five separate fictitious online accounts. Password accuracy and recall time were measured following both a short-term (10-minute) and long-term (1-week) delay. Results indicated that passwords were more quickly generated and accurately recalled when they were generated using the image-based mnemonic technique or proactive password restrictions alone, as opposed to the text-based mnemonic technique. Furthermore, use of the image-based mnemonic technique resulted in the generation of passwords that were more resistant to forgetting. Implications and future research considerations are discussed.
Password Authentication from a Human Factors Perspective: Results of a Survey among End-Users
Authors: Hoonakker Peter , Bornoe Nis , Carayon Pascale
Published: January 2012

Considering that many organizations today are extremely dependent on information technology, computer and information security (CIS) has become a critical concern from a business viewpoint. CIS is concerned with protecting the confidentiality, integrity, accessible information, when using computer systems. Much research has been conducted on CIS in the past years. However, the attention has been primarily focused on technical problems and solutions. Only recently, the role of human factors in CIS has been recognized. End-user behavior can increase the vulnerability of computer and information systems. In this study, using a large questionnaire survey among endusers, we examine password behavior of end-users.
Managing Ergonomics Course Projects in Operational Facilities So That Everyone Benefits
Authors: Johnson Steven L.
Published: January 2012

This paper presents methods of managing ergonomics course projects at operational facilities at the senior-level of an industrial engineering curriculum. Incorporating external projects into the course provides the students with an opportunity to apply the material that they have learned in class, as well as experience the issues related to applying the concepts in the “real world.” This paper discusses the benefits and challenges of conducting external projects. In particular, the methods of selecting projects, assigning groups, documenting progress, presenting results and assigning grades are discussed. Effectively managed projects can be a very beneficial learning experience for the student, as well as provide visibility for the university, department and discipline. In addition, experience has shown that the implementation of the recommendations made by the students can provide significant improvements for the participating companies.
A Case Study on the Backpack Weight of School Students
Authors: Loewenhardt Ruth A. K. , Ergo Elegant
Published: January 2012

This case study looks at the perceptions and measurements of backpack weight with regards to elementary, middle and high school students as studied during the American Occupational Therapy Association's National Backpack Awareness Day in Pleasanton, California. School students participated in the weigh-in with high school volunteers assisting an ergonomics consultant with measurements. Two consecutive years were compared and results suggest that the middle school students carry the greatest backpack weight as compared to their percentage of body weight. Perceptions of the students regarding the backpack weight indicated a self-reported discomfort with the amount to be carried each day specifically due to the requirements of their teachers. It is through education of backpack awareness that educators and students should work together to reduce the load that each student needs to transport on a regular basis.
Avoiding Misrepresentation in Forensic Human Factors
Authors: Nemire Kenneth
Published: January 2012

Every aspect of human factors consulting in litigation presents opportunities and challenges for acting in an ethical manner. This article discusses three types of misrepresentation that pose ethical problems: (1) disregarding information, (2) misrepresenting existing research, and (3) misrepresenting facts in a case. These examples are demonstrated in the context of three different lawsuits involving forensic human factors experts. The article concludes with a discussion of the role of the forensic expert to help reveal the truth, and a suggestion to revise the Human Factors and Ergonomics Society Code of Ethics.
Forensic Human Factors Results in Increased Pedestrian Safety
Authors: Johnson Daniel A.
Published: January 2012

Falls, a major cause of serious injuries, often result from uneven sidewalks caused by tree roots. The jurisdiction (city or county) may say the fall was the outcome of the victim's “inattention” and do nothing to eliminate the hazard. But accurate measurements of an irregular rise of sidewalk demonstrated to the city that a recognized hazard did exist and its defective maintenance contributed to the fall. The outcome was a financial award to the victim. Remedial actions were taken to reduce the chance of future falls on this and other city sidewalks.
Is Human Reliability Relevant to Human Factors?
Authors: Boring Ronald L. , Roth Emilie , Straeter Oliver , Laumann Karin , Blackman Harold S. , Oxstrand Johanna , Persensky Julius J.
Published: January 2012

This paper presents a number of views from a panel discussion on the relationship between human reliability analysis (HRA) and human factors. HRA emerged concurrently with the field of human factors and now features a nearly fifty-year shared history. While built on human factors, HRA distinguished itself early on from human factors due to its emphasis on predicting human performance. While one of the major focus areas of human factors has been improving the design of novel systems to optimize human performance, HRA has largely focused on predicting human performance for as-built systems. Over time, as HRA became closely tied particularly to the nuclear energy industry, it increasingly became a field associated more with reliability engineering than human factors. Yet, the similarity to human factors has not abated, nor has the opportunity for the two fields to cooperate. Human factors research provides the empirical basis to support predicting human performance in HRA. Importantly, HRA continues to benefit human factors by providing: (1) a framework for modeling human performance, (2) an example of how a human factors discipline can be seamlessly integrated with an engineering field, and (3) insights on how predictive modeling may be used as a system design tool.
Trends in Anthropometric Measures in U.S. Air Force Aircrew Survey Data
Authors: Choi Hyeg Joo , Zehner Gregory F. , Hudson Jeffrey A. , Fleming Scott M.
Published: January 2012

In 2008 a USAF Aircrew Sizing Survey project was launched. This survey is the first 3D whole body anthropometric survey of USAF aircrew. The primary purpose of this survey is to collect traditional anthropometric measurements, demographic information, and 3D data for body shape information on current aircrew personnel for use in crew station and protective equipment design. The specific aim for this paper is to compare the data collected to date with other available USAF aircrew anthropometric data as well as two extracted data sets, called JPATS (Joint Primary Air Training System) and JSF (Joint Strike Fighter) CAESAR (Civilian American European Surface Anthropometry Resource) which are currently being used as USAF design guidelines. The results from the comparisons between these survey data and available Air Force Survey data represent chronological trends in body dimensions for male and female aircrew. In addition, the noted anthropometric differences between the 2008–2009 survey data and the two extracted data subsamples (JPATS and JSF CAESAR) will help to determine the appropriateness of these subsets as substitute aircrew databases.
Healthcare Workers' Perceptions of Information in the Electronic Health Record
Authors: Russ Alissa L. , Saleem Jason J. , Justice Connie F. , Hagg Heather , Woodbridge Peter A. , Doebbeling Bradley N.
Published: January 2012

Electronic health record (EHR) systems and health information technology (IT) hold unrealized potential for improving the quality, continuity, and safety of medical care; they can also introduce new gaps in care and present unique challenges for healthcare workers. We conducted 14 key informant, semi-structured interviews at a large Veterans Affairs Medical Center and asked healthcare employees why paper use persists despite a fully implemented EHR. In this investigation, we performed a secondary analysis on interview data to identify characteristics of information technology (IT) that are important to support healthcare workflow. As a result of this study, 17 distinct information characteristics emerged; in this document, we provide detail on five characteristics that were often cited as desirable for workflow but insufficiently supported by health IT: 1) customizable, 2) prioritized, 3) trendable, 4) locatable, and 5) accessible. Results from this study reveal key electronic information characteristics for healthcare workflow and have implications for patient safety and future health IT designs.
Documentation in a Medical Setting: Effects of Technology on Perceived Quality of Care
Authors: DeBlasio Julia , Walker Bruce N.
Published: January 2012

The authors examine the social impact of introducing advanced exam-room technologies to the doctor-patient interaction. A total 342 participants viewed one of several video conditions portraying a physician conducting a medical interview in which he used one of 5 documenting methods/devices (nothing, pen and paper, PDA, desktop computer, wearable computer). After viewing the interaction, participants completed a series of questionnaires evaluating their general satisfaction with the quality of care (QoC) delivered during the medical interview. Results reveal that the type of technology used has a significant effect on QoC ratings. Though advanced technology offers the opportunity of better healthcare delivery, there may be a trade-off with lower ratings of interpersonal interactions.
NT-SEEV: A model of attention capture and noticing on the Flight Deck
Authors: Wickens Christopher , McCarley Jason , Steelman-Allen Kelly
Published: January 2012

N-SEEV is a model that predicts the noticeability of events that occur in the context of routine task-driven scanning across large scale visual environments. The model is an extension of the SEEV (salience, effort, expectancy, value) model, incorporating the influence of attentional set and allowing the possibility of a dynamic environment. The model was validated against two empirical data sets. In a study of pilot scanning across a high fidelity automated 747 cockpit, the SEEV component of the model predicted the distribution of attention with correlations of 0.85 and 0.88. In a lower fidelity study of pilot noticing of the onset of critical cockpit events (flight mode annunciators) the model predicted differences in noticing time and accuracy with correlations (across conditions) above 0.95. Other properties of the model are described.
A Componential Model of Human Interaction with Graphs: VII. a Review of the Mixed Arithmetic-Perceptual Model
Authors: Gillan Douglas J.
Published: January 2012

This paper provides a summary of the development and evaluation of a componential model of graph reading called the Mixed Arithmetic-Perceptual (MA-P) model. A review of the history underlying the development of the model begins the paper. The second section describes the research used to test the predictions from the model and to further develop it. The third section integrates the research to produce a single omnibus version of the MA-P model. Finally, the fourth section projects the future of the MA-P modeling approach, for specific versions of the model, additional research, as well as applications.
Evaluation of Mouse and Touch Input for a Tabletop Display Using Fitts' Reciprocal Tapping Task
Authors: Sasangohar Farzan , MacKenzie I. Scott , Scott Stacey D.
Published: January 2012

User performance with a tabletop display was tested using touch-based and mouse-based interaction in a traditional pointing task. Dependent variables were throughput, error rate, and movement time. In a study with 12 participants, touch had a higher throughput with average of 5.53 bps compared to 3.83 bps for the mouse. Touch also had a lower movement time on average, with block means ranging from 403 ms to 1051 ms vs. 607 ms to 1323 ms with the mouse. Error rates were lower for the mouse at 2.1%, compared to 9.8% for touch. The high error rates using touch were attributed to problems in selecting small targets with the finger. It is argued that, overall, touch input is a preferred and efficient input technique for tabletop displays, but that more research is needed to improve touch selection of small targets.
Dynamic Load Moment Exposure and Spine Function Impairment
Authors: Marras William S. , Lavender Steven A. , Sue A. , Splittstoesser Ferguson Riley E. , Yang Gang
Published: January 2012

A prospective study was performed in distribution center environments in order to determine which physical exposure measures related to a reduction in low back function. Workers in 50 distribution jobs employed in 21 distribution centers were monitored over at least a 6 month period for changes in spine function. Job exposures were monitored with a sonic-based exposure tracking system (laboratory in a backpack) that captured 197 physical exposure metrics per lift. Based upon the database containing over 60,000 lifts, a multivariate model was developed capable of predicting jobs characteristics associated with a decrement in spine function over time. The sensitivity and specificity of the model were 85% and 87.5%, respectively. These results provide valuable information for the control of risk in these environments and offer valuable insight regarding the biomechanical functioning of the spine.
The Need for a Lower Extremity Risk Assessment Model
Authors: Reid Christopher R. , McCauley-Bush Pamela , Karwowski Waldemar , McMullin Dianne L.
Published: January 2012

Current ergonomic risk assessment tools do not assess possible occupational (extrinsic) and personal (intrinsic) risk factors for the lower extremity regions of employees. This document proposes that it is possible to develop a lower extremity risk assessment (LERA) model for quantifying such risks. A literature review was conducted for work-related musculoskeletal disorders of the lower extremity that affect the nervous, muscular, vascular, and skeletal systems. This initial model of LERA was developed using epidemiological literature and subject matter expert opinion specifically for the knee joint and is considered a preliminary step towards quantifying the etiology of cumulative occupational knee disorders.
Menu Design for Touchscreen Interfaces
Authors: Kong Byung Don , Min Jung Sang , Myung RoHae
Published: January 2012

Touchscreens utilize a menu-based interface. Menu-based interfaces are an easy and efficient practice that considers the users' physical and cognitive characteristics. However, the users' behavioral characteristics using touchscreens is quite different from that required in a typical desktop environment. Hence, in this study, an efficient menu-based interface for touchscreens was investigated. It considered different users' physical and cognitive characteristics in a touchscreen environment. A dynamic menu layout was found to be more efficient in both physical and cognitive aspects compared to static menu layouts. Additionally, the columnar structure in menus did not influence users' task-performance in touchscreen interfaces.
The Persistence of Content Knowledge
Authors: Cullen Ralph H. , O'Brien Marita A. , Rogers Wendy A. , Fisk Arthur D.
Published: January 2012

Research has shown that changes in the way a website works or how it is laid out affects how well people are able to use that website. This study examined how changes in the content and procedures of a website-like system affect the way people recover from not being able to find information in that system. Participants were placed in one of four learning conditions, differing by the content and procedures taught for a simple website-like system. They were then tasked with finding certain pages in that system or systems with different procedures, content, or both. The first test (System B Online Test) showed that participants who had to learn new content were less efficient at finding that content, while participants who had to learn new content and procedures were the only ones slowed down. The second test (System C Online Test) showed that participants who had experienced a previous change in content responded to the new change faster, whereas people who started with inconsistent procedures (as compared to consistent) made fewer errors towards the end.
From UMPCs to Cell Phones: How Does Diminishing Screen Real Estate Affect Screen Access and Working Memory?
Authors: Byrd Keena S. , Caldwell Barrett S.
Published: January 2012

The goal of this study was to conduct preliminary research to inform system design for an advanced NASA assembly task. The primary objective of this research was to compare procedure-based task performance with three common mobile screen sizes: Ultra Mobile Personal Computer (7in/17.8cm), Personal Data Assistant (3.5in/8.9cm), and SmartPhone (2.8in/7.1cm). Study participants used these three screen sizes to view and complete a computer maintenance procedure. Results from 65 student participants indicated a significant difference in completion times between the three screen sizes (F(2, 120) = 690, p < 0.050), but no differences in subjectively-assessed cognitive workload, errors, or performance time. Competing task completion strategies were revealed through video analysis of access frequency and amount of time subjects spent reading the procedure before starting the experiment (F(2, 105) = 25.17, p<0.001). The 3.5 inch screen appeared to appropriately balance time spent reading the procedure before task start, and referring to the procedure during task execution.
Implicit Biases in Blame Allocation of Accidents across Organizational Components (Worker, Supervisor and Organization)
Authors: Haro Elizabet , Hung Yu-Hsiu , Yoo Hyun Seung , Littlejohn Robin
Published: January 2012

The objective of this study is to examine the relationship between implicit biases and blame allocation of accidents across organizational components (workers, supervisors, and organization). The ‘European American-African American’ and created ‘Latino-African American’ Implicit Association Tests (IAT) were used to measure the participants' implicit biases. The Accident Blame Allocation instrument was used to measure the participants' blame allocations, which included accident scenarios with pictures of male and female faces of European Americans, African Americans and Latinos. A total of 102 students, aged from 18 to 23, participated in the study. Results of the two IATs showed that the participants did not have obvious preference tendencies toward any ethnicity, and the ‘European American-African American’ and ‘Latino-African American’ IATs have a positive correlation with score of 0.48 ( p < 0.0001). Results of this study showed that implicit bias did not significantly correlate with accident blame allocation but that the participants' attitudes toward different ethnic groups affected their accident blame allocation patterns.
Speed-Accuracy Tradeoffs and the Role of Emotional Stimuli on the Sustained Attention to Response Task (SART)
Authors: Helton William S. , Kern Rosalie P. , Walker Donieka R.
Published: January 2012

In this study we investigated the properties of the sustained attention to response task (SART). In the SART, participants respond to frequent (high probability of occurrence) neutral signals and are required to withhold response to rare (low probability of occurrence) critical signals. We examined whether SART performance shows characteristics of speed-accuracy tradeoffs and in addition, we examined whether SART performance is influenced by prior exposure to emotional picture stimuli. Thirty-three participants in this study performed SARTs after being exposed to neutral and negative picture stimuli. Performance in the SART changed rapidly over time and there was a high correlation between participants errors of commission rate and their reaction time to the neutral targets (γ = -.72). SART performance was not significantly affected by emotional stimuli, but subjective reports of arousal were significantly affected by emotional stimuli.
Semantic versus Spatial Audio Cues: Is There a Downside to Semantic Cueing?
Authors: Barrow Jane H. , Baldwin Carryl L.
Published: January 2012

An auditory spatial Stroop paradigm was used to examine the effects of semantic and spatial audio cue conflict on accuracy and response time. Participants responded to either the semantic meaning or the spatial location of a directional word, which was either congruent (i.e. the word “right” being presented from the right) or incongruent (i.e. the word “right” being presented from the left). Contrary to our predictions, people responded more accurately to the semantic meaning of the directional words relative to spatial audio cues. An interaction between task type and congruency indicated people found it more difficult to ignore the semantic content of the word when performing the location version of this task relative to ignoring the location in the semantic task. Implications of these results for use in driver collision-avoidance warning systems are discussed. The current results indicate that performance benefits gained by the use of directional words in combination with spatial audio may be offset by greater detriment to performance when the warning system presents unreliable or incongruent semantic information.
Intelligibility of bone-conducted speech at different locations compared to air-conducted speech
Authors: Stanley Raymond M. , Walker Bruce N.
Published: January 2012

Bone-conduction transducers offer a unique advantage for radio communication systems, allowing sound transmission while the ear canals remain open for access to environmental sounds, or plugged for blocking of environmental sounds. This study compared the intelligibility of noise-degraded speech presented through bone-conduction hearing administered at different locations, and through air-conduction. Speech intelligibility was assessed using the Diagnostic Rhyme Test. Speech intelligibility was reduced for all of the bone-conduction hearing locations, relative to air-conduction hearing. There were also differences in performance for the various bone conduction locations. These results suggest that given noise-degraded speech, the performance decrement from using bone conduction will have to be weighed against the benefits of being able to dynamically block the ear canal, or leave it open, as situations require. Further, the choice of bone conduction transducer location would need to weigh possible performance differences against the various practical advantages of each location.
Detecting Critical Patterns in Maternal-Fetal Heart Rate Tracings over Time
Authors: Anderson Brittany L. , Scerbo Mark W. , Lee A. Belfore , Abuhamad Alfred Z.
Published: January 2012

The present study examined how individuals detect critical patterns in MFHR tracings in single and multiple monitor displays. Two studies were performed, varying the number of critical signals presented within displays. In the first study, the number of critical signals increased with increases in the number of displays. In the second study, the number of signals remained constant across display conditions. The results from Study 1 showed no decrement for either display condition; however, fewer critical signals were detected in the multiple display condition. In Study 2, there was no vigilance decrement nor was there a difference in number of signals detected for display condition. However, significantly more false alarms were committed for the multiple display condition. Although no definitive conclusion can be reached regarding vigilance performance and multiple displays, there is cause for concern from a clinical perspective about the degraded ability to detect signals from multiple displays. These findings highlight the need for additional research on factors that affect the ability to monitor MFHR tracings, particularly in clinical settings.
Judging the Lengths of Curved Lines
Authors: Gillan Douglas J.
Published: January 2012

Studying the psychophysical functions that physical length of lines to the perceived length is critical for the understanding of the perception of displays like maps and graphs. Previous research has examined straight lines and the circumference of a circle. The present research investigated the judgment of the length of both straight and curved lines, varying from slight to moderately high degrees of curvature and varying in length. In two experiments, the psychophysical functions relating perceived length to the physical length of a line was found to be similar for straight and curved lines. The Stevens' Law exponent for the straight and curved lines tended to be close to 1.0 for all lines, independent of curvature. The paper discusses spatial judgments, with a focus on the differences in the psychophysical functions or the various types of lines.
Decision Analysis Using Policy Capturing and Process Tracing Techniques in a Simulated Naval Air-Defense Task
Authors: Lafond Daniel , Champagne Julie , Hervet Guillaume , Gagnon Jean-François , Tremblay Sébastien , Rousseau Robert
Published: January 2012

Research in cognitive systems engineering (CSE) and decision support requires an understanding of the psychological processes involved in a given task. The purpose of the present study is to investigate how policy capturing and process tracing may help understand the decision mechanisms involved in a naval air-defense task and characterize how human decision making effectiveness can be improved. We report results from a study in which participants performed a threat evaluation and weapons assignment task within a naval air-defense microworld. Policy capturing and process tracing techniques provide both converging perspectives and complementary insights into complex decision making processes.
Skin and Bone Surfaces for a Three-Dimensional Kinematic Hand Model
Authors: Park Daewoo , Armstrong Thomas J. , Woolley Charles B. , Best Christopher J.
Published: January 2012

We have previously described the development of a 20 link, 25 degrees-of-freedom three-dimensional kinematic model of the hand (Buchholz and Armstrong 1992, Choi and Armstrong 2006). Each link corresponds to a segment of the hand. We also showed how this model can be used to predict 1) hand posture and finger placement using contact algorithms and 2) the space required for the hand to reach for and grasp work objects. The present model uses an array of points based on truncated cones to describe the skin surface. This study aims to develop models for describing the surface of the hand that are congruent with the anatomic structure of the hand. These models will improve the model predictions of finger placement and posture, of the space required by the hand, and the hand image. In addition, we also aim to develop models that describe the bones in the hand that will make it possible to study tendon excursions, loads and injuries. Graphic files that describe the surfaces of the hand and the bones were generated from multiple computed tomography images of adult human hands. The centers of flexor and extensor tendons were also identified in the images and located with respect to the above surfaces. These anatomical features were then scaled and added to the link structure of the biomechanical hand model.