bluuebunny/crossref_metadata_2025 huggingface dataset:
A Comparison of Direct and Indirect Input Devices in a Volumetric Interactive Virtual Environment Workspace
Authors: Eggleston Robert G. , Janson William P. , Aldrich Kenneth A.
Published: January 2012

The purpose of this study was to evaluate the impact of two different types of input devices on psychomotor performance in a “full” 3D (volumetric) virtual environment. Three subjects used both a direct input device (hand-held stylus) and an indirect input device (6 degree of freedom, fixed mounted force device) to accomplish aimed movement to a target located in one of eight depth planes. Directness was characterized in terms of action space and perception space coincidence and natural kinematic arm-hand movements. Different instructions were used to place different demands on coordination of movement. Aim point performance was evaluated in terms of aiming speed and accuracy, and steadiness at the terminal point. A descriptive analysis showed consistently better performance on all measures with the direct device. A statistical analysis confirmed these trends, although significance often was not always achieved due to limited experimental power. In general, the results suggest an advantage for the direct input device in the range of 30% to 73% across target locations, depending on type of performance measured. The data are discussed in terms of action and perception space coincidence and the coordination of the multiple degrees of freedom property of external input devices.
Trade-offs between Spatial and Temporal Resolution in Driving Unmanned Ground Vehicles
Authors: van Erp Jan B.F.
Published: January 2012

Remote vision for steering unmanned vehicles is generally facilitated by on-board cameras. Due to limited bandwidth data-links, a trade-off exists between spatial and temporal image resolution.

In the present experiment, objective performance of military driving instructors was measured on a standardized task-battery in a fixed-base driving simulator. The results showed that the optimum choice of spatial and temporal resolution is task specific. The lack of an interaction between both the factors pleads for some provision for the operator to modify these parameters when switching between tasks.
Separation Maintenance in High-Stress free Flight using a Time-to-Contact-Based Cockpit Display of Traffic Information
Authors: Knecht William , Hancock Peter
Published: January 2012

We evaluated the navigational performance of commercial airline pilots in simulated free flight conditions using two cockpit displays of traffic information (CDTI). One display presented minimal essential navigation information. The other added color-based time-to-contact (Tc), minimum-range, and altitude intent information. New metrics of separation maintenance were developed. Results indicated performance gains for the CDTI that automatically calculates and displays conflict-alerting information. Recommendations are made for advanced avionics for use in free flight.
An Evaluation of Unisensory and Multisensory Adaptive Flight Path Navigation Displays: An Initial Investigation
Authors: Moroney Brian W. , Nelson W. Todd , Hettinger Lawrence J. , Warm Joel S. , Dember William N. , Stoffregen Thomas A. , Haas Michael W.
Published: January 2012

Unisensory and multisensory adaptive interfaces for precision aircraft navigation were tested under varying concurrent task demands. Participants - 12 USAF pilots - were required to perform a simulated terrain-following, terrain-avoidance navigation task, including evasive maneuvers, while also performing: (1) no additional task; (2) a visual search task; or (3) an auditory monitoring task. Real-time performance efficiency, as measured by lateral deviation from the flight course, was used to activate the adaptive navigation displays consisting of a visual azimuth steering line on the head-up display, a spatial auditory beacon, or a combination of the two displays. A completely factorial, within-subjects design was used to assess the effects of secondary task load and adaptive interface configurations on flight performance. The results indicated that the efficacy of multisensory, adaptive navigation displays is mediated not only upon the supplementary task confronting the pilots, but also upon the type of flight task performed and the strategies they adopted to acquire and use the information offered. Implications for the use of adaptive multisensory displays in tactical aircraft displays will be discussed.
Managing Uninhabited Aerial Vehicle (UAV) Information Employing a Reduced Area / Depth Separated Display
Authors: Wesler Mary Mc. , Lucas Jesse R. , Gallimore Jennie J. , Marshak William P.
Published: January 2012

Command and control in a military battlefield environment requires a large amount of information to be integrated rapidly. In situations where Uninhabited Aerial Vehicles (UAVs) are implemented, a single controller may have to supervise many UAV assets. During any given mission, the controller is required to manage multiple UAV elements such as flight parameters, target locations, and aircraft locations. This series of studies investigated the effect of display type on information presentation during a visual search task. The displays tested included a multi-depth display, a single display (toggling between two windows), and multiple displays set side-by-side. The multi-depth display is known as a True-Depth Display (TDD) which creates depth by the simultaneous use of two display surfaces in one visual space by means of a combiner glass. No significant differences were found between the use of a TDD and multiple displays in the first study. A significant difference was found between the use of a single display and multiple displays in the second study. Having no other significant effects or interactions might indicate that when space is limited, such as in a command and control vehicle, it appears as though the TDD will perform adequately when response time and accuracy are important for simple search tasks.
Perceptual and Conceptual Processing in Expert Cue Pattern Recognition
Authors: Fiore Stephen M. , Jentsch Florian , Oser Randall , Cannon-Bowers Janis A.
Published: January 2012

In this paper we describe an investigation of differences in cue-pattern recognitional strategies among expert aviators. Military instructor pilots were presented with meaningful and random configurations of instrument gauges. Tests of perceptual and conceptual ability in reading the instruments showed dissociations in performance across the differing configuration types. Results are discussed in relation to cue-pattern recognition processes and expertise.
Cutting Stock Problem: A Heuristic Solution Based on Human Intuitive Strategies
Authors: Kopardekar Parimal , Mital Anil
Published: January 2012

The goal of the cutting stock operation is to maximize the material utilization by laying out maximum number of parts on a sheet. Historically, laying of parts on a sheet has been performed by humans. As the manual process is very time consuming, a number of heuristic and mathematical algorithms have been developed in recent years. However, these algorithms do not guarantee higher utilizations than those achieved by human operators. This study investigated the feasibility of extracting and generalizing the involved human strategies in laying out parts. The results indicated that it is possible to extract and form generalized strategies leading to higher utilization. A group, trained with these strategies, achieved higher utilization than the untrained group. The trained group also achieved higher utilization than the most promising mathematical algorithm. This implies that these strategies can be used to train new operators. Using these strategies and automation aids such as a graphics software, the layout process will be much faster and produce high material utilization.
What is Command and Control Coming to? Examining Socio-Cognitive Mediators That Expand the Common Ground of Teamwork
Authors: McNeese Michael D. , Perusich Karl , Rentsch Joan
Published: January 2012

The design of command and control centers has undergone significant changes in recent years. In contrast to traditional human factors, contemporary approaches to the design of future command posts will necessarily engage various socio-cognitive activities that lead to effective and efficient teamwork. This paper provides a description of the contemporary “Living Lab” approach and the presentation of a study involving the use of socio-cognitive mediators within a simulated command post environment. The roles and outcomes of team member schema similarity and fuzzy cognitive maps (as two distinct types of mediators) are presented along with their use in a complex, situated problem domain involving AWACS command and control operators. Implications are drawn that suggest how socio-cognitive mediators may be used to expand and understand the common ground of teamwork and how this applies to the envisioned design of command and control centers.
Event Representations: Communicating Change Information in Supervisory Control
Authors: Christoffersen Klaus
Published: January 2012

There has traditionally been relatively little emphasis on temporal and event-oriented information in the cognitive engineering literature on representation design for supervisory control environments. Not surprisingly perhaps, current methods in these settings for capturing and representing events (patterns of behavior in the monitored system), are relatively crude. The need for more sophisticated representations of this type of information will become increasingly urgent as a result of evolving operations practices in many industries. This paper presents an argument for the importance of event information and briefly reviews how current representational techniques can make events hard for operators to observe and interpret. The paper concludes with a discussion of some of the challenges to be met in developing a principled basis for the design of more effective event representations.
Why Mission Control Works: Supporting Cognition and Collaboration in Distributed, Dynamic Worlds
Authors: Chow Renée
Published: January 2012

Studies of failures have dominated human factors research in complex, dynamic domains. The goal of this panel, however, is to use a case study of success - space shuttle mission control - to explore how robust problem-solving and effective collaboration among distributed, functionally distinct agents can be facilitated. This panel brings together human factors researchers and systems designers who are familiar with mission control to discuss the cognitive factors, organizational practices, and technological innovations that contribute to the success of space shuttle missions. As with other complex domains, economic and technological pressures are threatening mission control's bases for success. These pressures (e.g., budget/staff reductions, more complex technology, and longer, more remote missions) are intensifying demands for “smarter”, more autonomous computer support tools. Therefore, this panel explores approaches for designing intelligent systems and automation that perform as “team players” in challenging operational environments - where effective collaboration constitutes the key to success.
Situation-Oriented Displays of Space Shuttle Data
Authors: Thronesbery Carroll , Christoffersen Klaus , Malin Jane
Published: January 2012

Event-based, or situation-oriented, logs of Space Shuttle data were evaluated for their support of flight controllers in reviewing operations. An intelligent system was developed to bundle and annotate the data describing an operational event, or situation. A display tool was also developed to show this situation information to flight controllers, aiding the review of procedure operations and anomalies. Finally, flight controllers informally evaluated the situation displays in the context of scenarios based on recorded mission data. They confirmed that the situation-oriented logs provide useful information for reviewing operations and help the reviewer find relevant details associated with a procedure or anomaly. Initially, these logs were designed to support off-line tasks like shift hand-overs, anomaly analysis, and writing post-mission reports. As we learn more about how to support a quick understanding of events, we can better answer the challenges of real-time monitoring of large amounts of data and management by exception.

Miller's 7±2 is an oft-cited but misleading heuristic in user interface design. Miller extracted this rule of thumb by examining data on memory span, among other things. However, memory span procedures measure short-term memory at its upper limits and thereby greatly overestimate humans' ability to easily hold in mind unrelated, linguistic material. Justifications for using a maximum of 3 items as a design heuristic are presented.
Designing the Best Team for the Task: A Method that Combines Algorithms, Heuristics, and Expert Judgment
Authors: MacMillan Jean , Paley Michael J. , Serfaty Daniel , Levchuk Yuri N.
Published: January 2012

This paper describes a systematic, formal, quantitative approach for designing teams. The method develops a quantitative hierarchical mission or goal structure that specifies the parallelism, sequence, and structure of the tasks that must be accomplished in order to complete the team's mission. Using that quantitative task structure, we apply a systems engineering approach that describes organizational performance criteria as a multi-variable objective function to be optimized. We work closely with subject matter experts to develop the task structure and to specify the criteria to be optimized for the team (e.g., the distribution of workload among team members or the time needed to complete the mission). This process is iterative, with team designs produced, reviewed by domain experts, and modified. The method is currently being applied to two organizational design problems for Navy teams, and shows promise as a tool for human factors practitioners dealing with team design and organizational redesign issues.
Towards Tailor-Made Team Training
Authors: Bots Michael , Schaafstal Alma
Published: January 2012

This paper focuses on the relationship between team performance, task architecture and the design of team training. In exploring this relationship an experiment was carried out in which the effect of two cross-training instructions was examined on the performance of teams with an open versus fixed task architecture. The results indicate that an interaction generic instruction, consisting of general rules and guidelines, has a positive effect on the performance of teams with an open task architecture. The results also show that teams characterized by an open task architecture benefit the most of an explicit cross-training instruction focussing on task related interactions. The results of this research study will be discussed in terms of their relevance for designing effective training interventions, which take relevant team and task characteristics into account.
Using Automation to Support Decision Making: Challenges and Training Research Requirements
Authors: Oser Randall L. , Jentsch Florian G. , Bowers Clint A. , Salas Eduardo
Published: January 2012

Many of today's complex environments require operators to interact with sophisticated systems that are multi-modal and automated. Despite considerable advancements in systems design, performance is not always optimal. Research suggests that one reason for non-optimal performance may be due to inaccuracies in operators' understanding of how these complex systems work. These inaccuracies may lead to: (a) a bias towards use of automation, (b) over-trusting the automation, or (c) diffusing responsibility to the automation. Unfortunately, few theoretically-derived strategies exist to guide training design that builds an appropriate understanding of how the system works in addition to how to work the system. In this paper we take a training perspective to describe how and why automation may or may not be used to support decision making. Specifically, the paper will briefly: (1) discuss the training problems with human-computer teams, (2) describe a number of theoretical underpinnings for the problem, (3) provide an overview of challenges for addressing the problem, (4) forward two potential research areas that may mediate the challenges, and (5) describe expected payoffs for research in these areas.
Abais: Affect and Belief Adaptive Interface System
Authors: Hudlicka Eva , Billingsley John
Published: January 2012

We describe an Affect and Belief Adaptive Interface System (ABAIS) designed to compensate for performance biases caused by users' affective states and active beliefs. The ABAIS architecture implements an adaptive methodology consisting of four steps: sensing/inferring user affective state and performance-relevant beliefs; identifying their potential impact on performance; selecting a compensatory strategy; and implementing this strategy in terms of specific GUI adaptations. ABAIS provides a generic adaptive framework for exploring a variety of user assessment methods (e.g., knowledge-based, self-reports, diagnostic tasks, physiological sensing), and GUI adaptation strategies (e.g., content- and format-based). The ABAIS performance bias prediction is based on empirical findings from emotion research, and knowledge of specific task requirements. The initial ABAIS prototype is demonstrated in the context of an Air Force combat task, uses a knowledge-based approach to assess the pilot's anxiety level, and modifies selected cockpit instrument displays in response to detected increases in anxiety levels.
The Evaluation of the Siemens C10 Mobile Phone: - Usability Testing Beyond “Quick and Dirty”
Authors: Suwita Martin Böcker and Anne
Published: January 2012

In spite of the general appreciation of the need for usability evaluation, systematic evaluation studies of new products are the exception. This paper describes the evaluation conducted at Siemens of the prototype for a novel interface of a cellular telephone. The interface design itself is presented followed by a description of the test method, the 80 subjects sample, and the results. The conclusions focus on lessons learnt through the study and on the need of integrating usability evaluation into the product cycle.
Expert/Novice Comparison of Abstraction and Extensibility in OBject-Oriented Design
Authors: Ryan Caspar , Al-Qaimari Ghassan
Published: January 2012

This paper describes the design and execution of an experiment for establishing the differences in cognitive activity and design strategies between expert and novice object-oriented designers. A three stage experimental session was used to track the evolution of a design through a number of changing specifications. The primary focus of the study is the abstraction level of a design and the effect of this factor on extensibility. This paper represents a work in progress in which the experiment has been designed and executed on a sample of expert participants with final analyses and results not yet available. Consequently, it is the intention of this paper to describe the processes of designing the experiment; the associated analyses and the effort that was taken to guard the internal and external validity of the study.
Evaluation of Typing Key Layouts for Stylus Input
Authors: Lewis James R. , LaLomia Mary J. , Kennedy Peter J.
Published: January 2012

We studied initial user performance with and preference for alternative typing-key layouts for typing with a stylus. Previous analyses have indicated that, after asymptotic practice with this kind of typing, users should type fastest with certain nonstandard layouts. Although asymptotic performance is important in selecting a layout, it also is important to evaluate initial performance with and preference for layouts. Twelve participants used paper models of six different layouts to type four sentences. The layouts were the QWERTY, Dvorak, standard alphabetic, square alphabetic, and two digraph-based layouts. Performance and preference favored the QWERTY over the other layouts. The square alphabetic layout took a distant second place. QWERTY should be a product's default layout even if users can type with only a single finger or a stylus. If the QWERTY layout is not feasible, designers should consider using the square alphabetic layout for limited typing or a digraph-based layout for extensive typing.
Workspace Control Diagrams and Head-Mounted Displays as Alternatives to Multiple Monitors in Information-Rich Environments
Authors: John Mark , Manes Daniel I. , Oonk Heather M. , Ko Hiekeun
Published: January 2012

In environments such as Navy command and control, supervision and multi-tasking are often hindered by a shortage of screen space. An obvious solution is to use more or larger monitors. An inexpensive and practical alternative is to use an interface that allows rapid switching between workspaces (screens of information), providing, in effect, a large virtual desktop. One potentially effective switching interface is a workspace control diagram—a meaningful arrangement of buttons, each of which provides access to and information for a particular workspace. In Experiment 1, participants best performed a task that required frequent navigation among workspaces using two real monitors but were nearly as proficient when using one monitor with a workspace control diagram operated by hot keys. In Experiment 2, participants performed concurrent tracking and monitoring tasks about equally using four monitors with all workspaces visible and using two monitors with a workspace control diagram. Additionally, we discuss the potential of a much more radical workstation design alternative: head-mounted displays.
Searching Hard-Copy (Paper) vs. Electronic (CRT) Documents: Role of Experience, Amount of Text Displayed, and Book Metaphor
Authors: Blinn Benjamin , Biers David W.
Published: January 2012

This study examined possible sources of differences in searching for information in hard copy (paper) reference books and electronic versions of the same document with powerful search tools. Two hypotheses were advanced—the amount of text displayed to the user at any one point in time and the book metaphor. To test this hypothesis, 30 users were asked to perform several search tasks utilizing each of three document modes (Hard Copy, Electronic Scrolling, Electronic Page Flipping) over three sessions under one of two page length (Short, Long) conditions. Results indicated that there were no differences in search time as a function of document mode; however, the two computer modes were preferred over hard copy. Results were interpreted in terms of user computer experience and the difficulty in using the hard copy documentation when the amount of index and text information displayed to the user is controlled.
Effect of Error Correction Strategy on Speech Dictation Throughput
Authors: Lewis James R.
Published: January 2012

The eight participants in this experiment used two different commercially available speech recognition dictation systems to complete a variety of reading transcription tasks. Participants enrolled fully in both systems. They received training in two correction strategies for both systems: multimodal correction (voice plus mouse plus keyboard) and hands-free correction (voice-only), and used both strategies during the experiment. The key findings were:

• Both dictation systems were equally accurate. • Throughput (corrected words per minute) was significantly (63%) faster using multimodal correction. • Speaking rates were the same for both systems and correction strategies, averaging around 105-110 utterances (words and commands) per minute. • Correction speeds for the multimodal correction strategy (13.2 seconds per correction) were significantly faster than (a little more than twice as fast as) those for hands-free correction (29.1 seconds per correction). • At the end of the experiment, participants indicated they significantly preferred the multimodal correction strategy.
Information for PDA Application Design: Calendar Entry and Name Length Statistics
Authors: Lewis James R.
Published: January 2012

Personal Digital Assistants (PDAs) are small computing devices that support a user's personal organization activities. Because they are small, PDAs have limited memory and display area. The first study determined the values of calendar entry statistics for computer calendar users. These statistics can help architects of PDA calendar programs design their programs to simultaneously (1) satisfy their users' requirements and (2) take up the least possible amount of memory in the PDA. The second study estimated the distribution of U.S. name lengths. This information is useful for designers of PDA software who need to present names to users in touch-screen buttons. The mean length of names was 13.8 characters with a standard deviation of 2.543 (presented in a last name, first name format). Thus, a touch-screen button that can show 20 characters should show a resident of the United State's complete name approximately 99% of the time.
Comparing In-Keyboard Pointing Devices: Considerations for the Practitioner
Authors: Sawin David A. , Ark Wendy
Published: January 2012

Pointing sticks and touchpads are the leading integrated pointing devices for portable computers. Yet research shows that users are frustrated with these devices. With WIMP interface firmly entrenched and mobile computer use drastically rising, attention must be paid to the virtues and limitations of integrated pointing devices. This article offers a mixture of qualitative and quantitative findings that clarify the issues and the design factors that affect performance and satisfaction with integrated pointing devices. Findings indicate that the rate-control pointing stick is a more efficient and preferred pointer to the position-control touchpad device, but that other design factors such as palm rest size, LCD technology differences, and device implementation differences might account for more variance in pointer effectiveness and user satisfaction than the device type itself. Contradictory findings in the recent literature are explained in terms of differences among these other factors. Practitioner guidelines for these technologies are also discussed.
Application of Cognitive Principles to the Design of Direct-to-Consumer Advertising of Prescription Medications
Authors: Wogalter Michael S. , Paine Corinna S. , Mills Brian J. , Smith-Jackson Tonya L.
Published: January 2012

This research sought to determine the formats of direct-to-consumer (DTC) drug advertisements that would facilitate communication of benefit and risk information. Fictitious DTC advertisements were designed to test the effect of integrated (risk/benefit information presented in a single textual unit) versus separated (risk/benefit information presented in separate, distinct textual units). These two formats were orthogonally combined with the presence or absence of color (red) to distinguish the risk information or the risk information was the same color (black) as the rest of the text. Also included was a fifth condition in which separated risk information was made extremely salient by using an enhanced warning style similar to that advocated by the ANSI Z535 warning standard. Lastly a sixth condition was a control that lacked risk information. The 144 undergraduates and community volunteers who participated were presented 6 DTC advertisements representing 6 design formats embedded within a realistic-looking but fictitious leisure magazine in a repeated measures balanced latin square design. Advertisement effectiveness was determined by measuring performance on a knowledge test of benefit and risk information. Participants also ranked ordered advertisements on the basis of effectiveness of communicating drug uses and risks. Results showed that the presence of physical features that distinguish the risk information from other text facilitated information acquisition and increased the perceived effectiveness ranks. Implications for the design of advertisements for products with potential risks are discussed.
Trunk Flexion Strategies during Sudden Loading
Authors: Lavender Steven A. , Andersson Gunnar B.J.
Published: January 2012

Sudden loading has been shown through epidemiological studies to be linked with onset of low back disorders. The objective of this work was to identify response strategies used by individuals when subjected to sudden loading of the torso and determine the biomechanical consequences of the strategies employed. Eighteen subjects experienced “expected” and “unexpected” loadings while holding either an empty box or a pre-loaded a box. Dependent measures were comprised of kinematic and electromyographic data. Based on trunk flexion measurements subgroups were subgroups using stiff and flexible response strategies were identified. Those using the flexible strategy had greater posterior muscle response (agonist) and less antagonistic response from the anterior muscles. This finding suggest that those employing a flexible strategy may ultimately have a greater risk of over-exertion injury during sudden perturbations
Human Factors Concerns in Enterprise Resource Planning (ERP) Solutions
Authors: Kleiner Brian M. , Bishu Ram R. , Drury Colin G. , Nair Madhu , Getty Robert , Muralidhar Ajoy
Published: January 2012

Manufacturing and service industries throughout the world are continuously finding methods to remain lean and profitable. This process had accelerated the globalization of manufacturing facilities. The motto “determine the most effective way of producing” has driven these efforts. The results are a change from a “production and operations management” philosophy, to a “supply chain management” philosophy. ERP systems are system software that integrates all the functions in an organization. The integration is provided across all functional frontiers of the organization. For example, different links in the supply chain may exist at different parts of the world, leading to differences in a wide range of attributes, e.g., culture, work hours, different governmental regulations, and different customer requirements for the same product. These differences necessitate the need for integration and ERP systems are prescribed to fill the need. ERP systems, as they are common to a wide range of industries, are sufficiently generic and understandably complex. Popular brand systems are “People Soft”, “Oracle”, “Bean” and “SAP”. While they promise considerable benefits to organizations that implement them, the process of implementation, in itself, is very complex, often lasting two to three years and costing more than 1$00 million. The human factors' concerns are many, and unfortunately may be, the main cause of the problems that have plagued the ERP systems.
Upper Extremity Exposure among Wood Processing Operators
Authors: Bao Stephen , Silverstein Barbara , Cohen Marty
Published: January 2012

The main goal of this study was to quantify risk factors, that may contribute to the development of musculoskeletal injuries, in a trimmer's job of a large sawmill. Two operators participated in this study and each was measured for two days when two different products were processed. Detailed observational methods were used to quantify task distribution, repetitiveness of hand exertion and work postures. Surface electromyographic (EMG) and electrogoniometric measurements were employed to quantify muscle loads on four muscles in the neck/shoulder and forearm regions, and postural loads of the right wrist and forearm. Results of task distribution showed that the operators spent about 76% of the time monitoring and positioning boards. Thus, ergonomic intervention measures may need to be focused on improvements on this task. Major risk factors found at this job were high repetitive hand exertion, awkward wrist postures, high hand force exertion and static shoulder muscle load.
Lifting Ability of Army Men and Women in Relation to Occupational Demands
Authors: Sharp Marilyn A. , Knapik Joseph J. , Hauret Keith , Frykman Peter , Patton John F.
Published: January 2012

The primary purpose of this study was to examine the relationship between the lifting strength of soldiers entering the Army and the physical demands of their job. The muscle strength and body composition of 169 male and 153 female recruits were measured prior to basic training. Each soldier's lifting capacity was compared to the lifting standards of their assigned job. Nearly all soldiers were able to meet the standard for frequent lifting; however, 56% and 77% of women could not meet the standard for occasional lifting in the heavy (45.4 kg) and very heavy (>45.4 kg) physical demand category, respectively.
Physiological Evaluation of the Effectiveness of Six Different Back Belts
Authors: Hasan Hadi , Freivalds Andris
Published: January 2012

Back belts lately have generated considerable debate as to their effectiveness. Eight male subjects wore six different back belts (wide and narrow, firm and flexible) while squat and stoop lifting a tote box at two loads, 15% MVC and 40% MVC. Four different physiological measures were recorded: 1) erector spinae EMG, 2) ratings of perceived exertion, 3) blood pressure and heart rate, and 4) low back compressive forces (Fcomp). A no-belt control condition was also tested. A general linear model revealed no significant differences in any of the physiological measures for either the type of belt or no belt used (p>0.05). However, load and posture showed significant (p<0.05) effects. Also, the body mass index (BMI) was a significant covariate, with higher ratings, blood pressure, heart rate and Fcompfor higher BMI. Overall, the results of this study add to the growing body of evidence that back belts may not offer a reduction in the physical stress associated with manual materials handling.
Valve Wheel Rim Force Capabilities of Process Operators
Authors: Attwood Dennis A. , Nicolich Mark J. , Pritchard Kelly K. , Smolar Tamara J. , Swensen Eric E.
Published: January 2012

The force that an operator is able to apply to a valve wheel depends on the location of the wheel and the orientation of the valve stem as well as the diameter of the wheel and the quality of the interface between the wheel and the hands. The objective of this study was to create a database that captured the maximum force that chemical and refinery workers can apply to crack open a valve equipped with a wheel actuator. Participants were 66 volunteer process operators and managers from a refinery and a chemical plant located on the Gulf Coast of the United States. Turning strength was measured by recording the force applied to the rim of the valve wheel during an isometric contraction in which there was no movement of the body. The data collected in this study clearly demonstrate a relationship between the posture of the operator, as defined by the height and orientation of the valve wheel, and the maximum turning force that can be applied. For a horizontal stem, the most force could be applied when the valve was in the knee or waist area. For vertical stem valves, operators appear to be able to apply the maximum force when the valve is located between the waist and the shoulder.
Applying Usability Methods to a Large Intranet Site
Authors: Grose Eric , Jean-Pierre Susan , Miller Dwight , Goff Robert
Published: January 2012

This paper describes the usability design process of a project web site within Sandia National Laboratories. Most web site designers can claim no more knowledge about their users than a focus group. This paper, however, describes the use of usability techniques such as structured interviews, card sorting, and usability testing to establish a usable information structure with which project personnel can be immediately productive. First tests of the information structure after card sorting produced correct performance on almost 80% of test trials. Innovative techniques to analyze card sort results and to perform usability testing should provide some useful tools to others interested in designing sites for usability.
Ergonomic Tenets and the Bottom Line
Authors: Rodrigues Clarence C.
Published: January 2012

This paper proposes and discusses Ergonomic Tenets that will help the Ergonomist be a “bottom line” contributor. In support of these Tenets, this paper describes how the ergonomics function at a Fortune 200 food corporation developed into a bottom line contributor through the development and implementation of an ergonomic multidimensional action plan. As a result of this program, there was a 40% reduction in total OSHA recordable injuries for the back, wrist, shoulder and neck. In addition, there was a 50% reduction in the number of workers' compensation claims and a 60% reduction in these costs for back and repetitive motion injuries. This translated to cash flow savings of over $3 million. Also, OSHA citations and fines dropped to zero from 389 and $1.4 million, respectively. In addition, this paper will explain a cost justification technique that used workers' compensation costs to help justify engineering projects that fell short of the Company's financial requirements.
What's so Hard About Bronchoscopic Surgery?
Authors: Tawil Andrea Z. , Thomas Geb , Lee John D. , McLennan Geoffrey
Published: January 2012

This study identified aspects of bronchoscopic surgery that are the most physically and mentally demanding in order to focus future technological improvements in areas that are likely to result in the greatest gains in procedure success rate. Seventeen bronchoscopic surgeries were observed and the three participating physicians and their assisting respiratory therapists filled out questionnaires to identify areas of particular challenge. The results indicate that the greatest difficulty in performing pre-biopsy navigation is physical demand. Needle and forceps biopsies are the most difficult tasks of the procedure, where brush biopsies are the least difficult, forceps the next, and needle biopsies the most difficult. The greatest demand for all biopsies was mental. Physicians would benefit from technological developments that aided biopsy location and execution.
Prescription Medication Information: Improving Usability Through Human Factors Design
Authors: Isaacson Judith J. , Klein Helen Altman , Muldoon Robert V.
Published: January 2012

Prescription medications are an important yet potentially hazardous part of outpatient treatment. Safe and effective use requires users to understand and follow instructions and heed warnings. Many pharmacies now provide customers with information sheets describing proper prescription use and precautions. These instructions are generally accurate but often not user-friendly. Human factors research suggested physical, cognitive, and organizational features that might enhance usability. In Study 1, we assessed sheets currently in use and then designed human factored information sheets that complied with recommendations from past research. In Study 2, human factored sheets for two medications were compared with a typical commercial version. Participants read a sheet of each type and referred to it while answering questions about the medication described. Read times and test times were significantly faster for the human factored sheets. Accuracy was significantly better. Participants overwhelmingly preferred the human factored sheets. This demonstrates the power of human factors to provide low cost solutions to potential health hazards.
On Managing Human Factors Professionals in the Software Industry
Authors: Henneman Richard L.
Published: January 2012

In this paper, the author outlines aspects of managing groups of human factors professionals in the software consulting industry. The observations are based on the author's experience in managing HF groups. Because of the HF professional's academic training and research orientation, the appropriate management model is closer to an academic model than to a corporate model.
Age and Gender Differences in Stress Responses during Simulated Driving
Authors: Matthews Gerald , Joyner Lucy A. , Newman Rachel
Published: January 2012

A study of group differences in susceptibility to stress during simulated driving is reported. 74 drivers participated, with approximately equal numbers of younger (18-25) and older (55-78) drivers, and of men and women. Stress was manipulated by exposing half the sample to a failure experience; frequent, uncontrollable skids. Following the stress manipulation, drivers' hazard perception, speed and vehicle control were assessed. Subjective state before and after the drive was assessed by questionnaire. It was hypothesized that older and female drivers might show greater subjective distress and performance impairment in the stress condition. Results showed that age was a stronger influence on performance than either gender or stress. Older drivers showed impairments in hazard detection and vehicle control, but appeared to compensate through slower speed. Older drivers and women showed higher levels of distress throughout the study, but these groups did not show any differential sensitivity to the stress manipulation. It is concluded that driver stress as a safety problem largely depends on individual differences, although group differences may be evident in other circumstances.
Advanced Travel Time Information and Drivers' Route Choice: Stated Preference Data
Authors: Katsikopoulos Konstantinos V. , Yawa Duse-Anthony , Fisher Donald L. , Duffy Susan A.
Published: January 2012

The effects of travel time information on drivers' route choice were investigated using a stated preference approach. Two experiments were run in which the average travel time and travel time variability (in the form of a range of travel times) along two routes were varied systematically. In the first experiment the travel time information was displayed on a sheet of paper to a participant seated on a desk. The results were consistent with previous findings that drivers choose the route that minimizes their average travel while attempting to keep travel time variability at a minimum. The second experiment utilized essentially the same experimental design but now travel time information was displayed in a virtual environment through which a participant had to drive. In this experiment, the results were consistent with the notion that drivers used the cognitively more efficient strategy of choosing the route that simply minimized their average travel time without always attempting to process travel time variability information. Implications for methodologies of gathering route choice data are also discussed.
Apple Pie a La Mode: Combining Subjective and Performance Data in Human Computer Interaction Tasks
Authors: Grounds Christopher B. , Ensing Annette R.
Published: January 2012

Frequently, two or three alternative interfaces will be empirically tested in a laboratory setting. Often, an argument arises concerning whether the performance or the preference of the user should be taken into account when making decisions about the best interface alternative. Usually, when making decisions regarding time-critical interfaces where mistakes can be costly, user performance outweighs user preference. Should user preference be disregarded at this point? This method attempts to combine users' preference and performance into one linear model. Using preference and performance data from an experiment that tested three alternative prototypes for monitoring air defense engagements, the results showed that one alternative performed better than the others, but was not preferred. After using the Brown-Gibson model for multi-attribute decision making, the resulting linear model showed that a different alternative that did not perform as well could actually be the superior prototype.
Work Domain Analysis for Identification of Training Needs and Training-System Design
Authors: Naikar Neelam , Sanderson Penelope M. , Lintern Gavan
Published: January 2012

Training needs analysis is critical for designing effective training systems. However, traditional techniques for analysing training needs are inadequate for capturing the demands of modern workplaces, where the primary role of workers is to adapt on-line to cope with unpredictable contingencies. By identifying the functional structure of a work domain, which is independent of particular events, work domain analysis provides a framework for informing the design of training systems that will allow workers to be trained to deal with unpredictable situations. To illustrate this argument, we outline a work domain analysis of a fighter aircraft and show how it may be used for identifying the training needs of fighter pilots and for deriving functional specifications for a training system for this work domain.
Helpful Feedback? Deriving Guidelines for Advanced Training Systems
Authors: Cook Catherine A. , O'Shea Amanda M. , Young Alison L. , Stedmon Alex W.
Published: January 2012

This paper reports initial work being conducted to investigate the applicability of existing feedback principles to the provision of system generated on-line feedback in complex Naval training systems. The majority of Navy team training in the UK is currently undertaken at high fidelity shore-based trainers, although in future there may be greater emphasis on training at sea. Technologies are now becoming available which may facilitate enhanced embedded training capabilities, whereby the training system itself generates and delivers trainee feedback. This paper describes work that has been carried out to identify existing feedback principles in order that their utility can be evaluated in this context. There was found to be a multiplicity of terms used to describe similar and related concepts. A classification of feedback types relevant to individual and team training was therefore developed, based upon content and timing dimensions. This was subsequently refined to focus upon training individual taskwork in a complex Naval Anti-Air Warfare task. Both classifications are described, together with details of an ongoing experimental programme that aims to evaluate the benefits of providing on-line feedback in complex training systems.
Training Self Explanation and Reading Strategies
Authors: McNamara Danielle S. , Scott Jennifer L.
Published: January 2012

This research examines the effectiveness of a training intervention program designed to improve strategies for learning from texts and to determine whether the success of this intervention depends on readers' individual differences. Previous research has shown that readers who self-explain text aloud understand more from a text and construct better mental models of the content. However, some readers are poor self-explainers and gain little from the self-explanation process. This study examined the benefits of providing training in the use of self-explanation to undergraduate college students. Effects of prior knowledge, reading skill, and working memory capacity were also examined in relation to the benefits of self-explaining and self-explanation training. We found that comprehension and the benefits of self-explanation depended largely on prior knowledge. Training was more effective for low-knowledge readers, but only in terms of improving memory for the text. Training did not improve the low-knowledge readers' understanding of the text at a conceptual level.
Effects of Hand Movement Lag on Discrete Manual Control Tasks in Virtual Environements
Authors: Chung K. M. , So Richard H. Y.
Published: January 2012

Most Virtual Reality applications involve manual manipulation and suffer from lags. Effects of lag in a virtual environment have received much attention. However, effects of target distance and width had not been analyzed in separation. A study has been conducted to investigate the effects of, and interactions among, hand movement related lag, target distance, and target width on manual task performance in a virtual environment. With a constant hand-related lag, hand Movement Time obeys Fitts' law (R2>0.85). Lags of 110 ms or above can significantly increase hand Movement Times and their effects have significant interactions with the effects of target width but not with target distance. This finding indicates that, in the presence of lag, the effects of target distance and width should be analyzed in separation.