bluuebunny/crossref_metadata_2025 huggingface dataset:
Ergonomics in Product Design Solves Manufacturing Problems: Considering the Users' Needs at Every Stage of the Product's Life
Authors: Dockery Christopher A. , Neuman Thomas
Published: January 2012

This paper demonstrates a systematic process for effectively considering in the product design process the ergonomics requirements of all who will interact with a product during its entire life cycle. This process goes beyond applications of ergonomics commonly found in industry. Development of the process is discussed. Several case studies from large corporations illustrate the application of the process including: deficiencies in conventional design processes relative to order of events, time requirements, effectiveness of the final design, and project scope. The product design process is discussed relative to when and how ergonomics should be included. Relationships are explored between ergonomics, the process, and the following concepts: design for manufacturability; design for serviceability; total quality management; customer driven products; flexible manufacturing.
Improving Ultrasound Systems by User-Centered Design
Authors: Aucella Arlene F. , Kirkham Thomas , Barnhart Susan , Murphy Lawrence , LaConte Kris
Published: January 2012

A series of user-centered design methods were applied during the development of an ultrasound system. The methods included hospital site visits, interviews with sonographers, videotapes of examinations and usability testing with simulations of the console and displays. Based on user feedback and preferences, over one-hundred design changes were made to both the console and control panel. The resulting system accommodates users through an adjustable control panel and display monitor. In addition, the control panel and corresponding operator interface software reflects frequency-of-use and sequencing-of-use of functions, leading to more efficient interaction with the system.
Quantitative Approaches to Team Communication and Performance: A Harmony of Systems Analysis Tools
Authors: Caldwell Barrett S.
Published: January 2012

Effective team performance in dynamic, high-consequence environments requires an interdisciplinary integration of human interactions with technological systems components. Several systems analysis approaches have substantial applications to the study of team communication and performance. This paper examines cybernetics and sociotechnical approaches to information exchange and coordination in human-technology systems. One component of cybernetics, based on quantitative feedback control engineering tools, can be effectively integrated with group communication and coordination principles from sociotechnical research. The author suggests ways in which these systems frameworks can be utilized and consolidated to support a more harmonious and quantitatively grounded examination of human performance in complex systems.
Designing an Intelligent Tutoring System Interface to Account for Personality Differences
Authors: Cushman Pauline K.
Published: January 2012

Intelligent Tutoring Systems have been designed for a variety of purposes. Much of the design effort has been aimed at the actual subject matter. Often ignored has been the critical nature of the interface. If the way people interact with computers is directly related to their personality, then systems should respond differently to different people. This paper describes the design of an interface for an Intelligent Tutoring System that, given the student's personality, will make adjustments in the style of interaction.
Intelligibility of Synthesized Voice Messages in Commercial Truck Cab Noise for Normal-Hearing and Hearing-Impaired Listeners
Authors: Morrison H. Boyd , Casali John G.
Published: January 2012

A human factors experiment was conducted to assess the intelligibility of synthesized speech under a variety of noise conditions for both hearing-impaired and normal-hearing subjects. Modified Rhyme Test stimuli were used to determine intelligibility in four speech-to-noise (S/N) ratios (0,5,10, and 15 dB), and three noise types, consisting of flat-by-octaves (pink) noise, interior noise of a currently produced heavy truck, and truck cab noise with added background speech. A quiet condition was also investigated. During recording of the truck noise for the experiment, in-cab noise measurements were obtained. According to OSHA standards, these data indicated that drivers of the sampled trucks have a minimal risk for noise-induced hearing loss due to in-cab noise exposure when driving at freeway speeds because noise levels were below 80 dBA. In the intelligibility experiment, subjects with hearing loss had significantly lower intelligibility than normal-hearing subjects, both in quiet and in noise, but no interaction with noise type or S/N ratio was found. Intelligibility was significantly lower for the noise with background speech than the other noises, but the truck noise produced intelligibility equal to the pink noise. An analytical prediction of intelligibility using Articulation Index calculations exhibited a high positive correlation with the empirically obtained intelligibility data for both groups of subjects.
The Time Delay to Start Evacuating upon Hearing a Fire Alarm
Authors: Proulx Guylène
Published: January 2012

An experiment was designed to observe the evacuation drills of occupants in four mid-rise apartment buildings. Each mid-rise building contained approximately 100 apartments, with 1 to 4 persons per apartment. All printed fire safety procedures stated that upon hearing the fire alarm all occupants should leave the building or move to an area of refuge, which means the movement of 100 to 200 people for each drill. The buildings chosen for this project were characterized as mixed-occupancy buildings; that is, they included adults, children, seniors and people with handicaps.

Occupants received a memo that an evacuation drill would take place during the upcoming week. The evacuations were planned and carried out with the full participation of the local fire departments. The evacuation drills were recorded on video-cameras located throughout the buildings. This paper presents the results regarding the time at which each occupant started to evacuate which varies between 30 seconds to over 24 minutes. Most occupants who heard the fire alarm started their evacuation approximately 2 1/2 minutes after the alarm activation. The impact of the alarm system, the location of alarm-bells, training and pre-evacuation actions are discussed.
Gathering and Recording Human-Related Causal Data in Marine and Other Accident Investigations
Authors: Hill Susan G. , Byers James C. , Rothblum Anita M. , Booth Richard L.
Published: January 2012

One of the missions of the U.S. Coast Guard (USCG) is to promote safety at sea through the prevention and mitigation of marine accidents. One means of preventing accidents is through the thorough investigation of the causes of marine casualties, the analyses of which can illuminate needed safety improvements. A study was conducted with the purpose of learning more about the USCG casualty investigation process, analyzing the data entry process, and making recommendations for improvements to the current computer system and the casualty investigation process. The study identified four major factors in the USCG system, particularly related to the reporting of human-related causes, which may have broad application to other safety professionals who contemplate the use of similar automated reporting and analysis systems. These widely applicable factors were:

• the reliability and completeness of the data can be affected by the investigators' understanding of the purpose and scope of the accident database; • the collection of human factors data can be overlooked and oversimplified; • the taxonomy/classification scheme affects data collected as well as data reported; • the computer interface used for data entry can affect the reliability, validity, and completeness of the human factors data.
Cognitive Strategies and Their Transformations as a Factor of Control Systems Safety in Emergencies
Authors: Venda Valery F. , Shelton R. Duane , Spikov A. A. , Jessau Cory , Chachko S. A.
Published: January 2012

In accordance with the laws of ergodynamics (Venda and Venda, 1994), it has been suggested that, when the condition in a control system goes from a normal situation to an emergency situation, human performance efficiency dynamics should be wave-like, first demonstrating a decrease due to different functional-structures, (normal and emergency), then transform from one to the other. Special emergency experiments were organized and It was found that operators used three different cognitive strategies that transformed from one to the other. This process caused the wave-like dynamics of performance efficiency. Operator's performance efficiency first decreased and, only after cognitive strategy transformations were completed, the efficiency then increased. The processes were then reconstructed and studied at the regional training centers in Krasnoyarsk (Siberia, Russia) and Kiev (Ukraine).
Oh! Say, Can You Hear that Train Coming to the Crossing?
Authors: Mortimer Rudolf G.
Published: January 2012

How effective is the horn on trains in alerting motorists, cyclists and pedestrians of the approach of a train to a highway-railroad crossing? Road users become aware of trains approaching crossings either by seeing them, hearing the warning horn or by warning devices at the crossing. Auditory warnings have some advantages over others, but practical problems of sound transmission and the noise environment of road users limit their effectiveness. Factors that affect the audibility of train horns and crossing bells are discussed. Train and crossing bells are generally effective for persons in their immediate environment, but are relatively ineffective for occupants of closed vehicles. Because of the lack of reliability of the detectability of auditory warning signals provided to motorists and others approaching rail-highway crossings, they should visually scan the tracks to ascertain the presence of a train.
Using the “Blur Tolerance” Technique to Predict and Optimize the Legibility Distance of Symbol Highway Signs
Authors: Schieber Frank
Published: January 2012

This study investigates the hypothesis that variations in symbol sign legibility distance can be accounted for on the basis of a sign's dependence upon high spatial frequency contours to convey critical information. Using digital image processing techniques, highway signs were blurred to remove all high spatial frequency information. A blur recognition threshold was established for each experimental sign by sequentially “deblurring” it until the observer could report the critical details defining its recognition criteria. Correlational analyses were then conducted to determine if legibility distance (collected in a previous study) could be predicted from the blur recognition threshold data. A significant correlation was observed between blur recognition threshold and sign legibility distance (r = −0.734, N=12, p < 0.001). That is, symbol signs with high levels of “blur tolerance” could be recognized at significantly greater viewing distances. These results support the application of new computer-assisted “recursive-blur” design techniques to optimize the effectiveness of symbol highway signs and related visual stimuli (see Schieber, Kline and Dewar, 1994).
A Cost Benefit Analysis Tool (CBAT) for the Management of User Interface Design and Evaluation Tasks
Authors: Bowen Charles
Published: January 2012

A user interface cost benefit analysis is an examination of the estimated costs associated with user interface design and evaluation tasks against the potential benefits to the software product. The Cost Benefit Analysis Tool (CBAT) is a human factors management tool written in SuperCard™. The tool is based on research by Mayhew (1993) and Mantei and Teorey (1988). CBAT supplements previous research efforts by the addition of more user interface tasks during typical software development lifecycle phases. The main cost benefit form is completed by means of electronic worksheets which are used to estimate both the costs and the benefits used in the overall analysis. Both cost and benefit estimates can be tailored to individual organizational needs. The tool provides the capability to print out data used to perform the cost benefit analysis and on-line help is provided for all worksheets. Future enhancements to CBAT are suggested in the following areas: additional user interface cost tasks and benefit estimates, the saving of analysis data into individual files, the inclusion of a graphic scheduling capability, and improvements to the software performance and flexibility.
Estimating Cognitive Complexity and the Need for Cognitive Task Analysis
Authors: DeVries Michael J. , Gordon Sallie E.
Published: January 2012

Because an increasing number of systems are being developed to support complex cognitive functioning, task analysis is commonly being augmented with cognitive task analysis, which identifies cognitive processes, knowledge, and mental models relevant to task performance. Cognitive task analysis tends to be lengthy and time-consuming, so designers frequently ask how they might know if it is actually necessary for a specific project. In this paper, we assume that much of the need for cognitive task analysis depends on the inherent “cognitive complexity” of the task. We present a model of cognitive complexity, and show how it was used to develop a computer-based tool for estimating relative cognitive complexity for a set of tasks. The tool, Cog-C, elicits task and subtask hierarchies, then guides the user in making relatively simple estimates on a number of scales. The tool calculates and displays the relative cognitive complexity scores for each task, along with subscores of cognitive complexity for different types of knowledge. Usability and reliability were evaluated in multiple domains, showing that the tool is relatively easy to use, reliable, and well-accepted.
Using a Distributed Interactive Simulation Environment to Investigate Machine Interface and Training Requirements
Authors: Winsch Beverly J. , Atwood Nancy K. , Quinkert Kathleen A.
Published: January 2012

In anticipation of changes brought about by increasingly powerful technologies and systems, the Combat Vehicle Command and Control (CVCC) program evaluated the use of an automated command and control (C2) system developed for the Abrams series tank. The system included a prototype C2 device with map display, navigation and digital messaging capabilities, an automated target acquisition system, and digital workstations in a Tactical Operations Center. Results yield a number of recommendations and represent the culmination of a five-year research program which has successfully utilized an iterative approach to investigate training and system design requirements for the prototype CVCC system. Data are discussed within the context of the need for design and training efforts aimed at alleviating the growing information management requirements faced by users of emerging C2 technologies.
Human Factors Certification of Systems
Authors: Wise John A. , Hopkin V. David , Stager Paul , Harwood Kelly
Published: January 2012

There is growing interest in the regulatory organizations (e.g., FAA, ICAO) to establish human factors based certification procedures for aviation technologies. This panel will discuss some of the issues debated during an international workshop on human factors certification of aviation technologies.
Identification of Desired System Features in an Advanced Traveler Information System
Authors: Kinghorn Rhonda A. , Bittner Alvah C. , Kantowitz Barry H.
Published: January 2012

This study evaluated consumer acceptance of variations of a currently available Advanced Traveler Information System (ATIS). We also wanted to determine if video demonstration was sufficient for observers to grasp the fundamentals of ATIS devices. A total of 109 licensed drivers viewed two videotaped demonstrations of TravTek, and then completed questionnaires. Principal Factor Analyses resulted in patterns of desired features and other composite variables used in regression analyses. Basic map features (e.g., vehicle position/location, outline of route) and voice features were the two dominant feature patterns. Other composite variables included understanding of the system capabilities, trust, self-confidence, tolerance of system errors, demonstration fidelity and attention. Results of the regression analyses indicated that different variables were significant predictors of each pattern of desired features.
The Effects of Sensory Modality and Information Priority on In-Vehicle Signing and Information Systems
Authors: Mollenhauer Michael A. , Lee Jaesik , Cho Ken , Hulse Melissa C. , Dingus Thomas A.
Published: January 2012

During this study, subjects drove an interactive driving simulator and were presented road sign information from a visual dash-mounted LCD display or from digitized auditory voice. Information priority was also manipulated in that subjects received all sign information typically present in the roadway environment, or only “filtered” high priority regulatory and notification information. The effects of display type and filtering on information recall, driver performance, and driver preferences were measured. The results indicate that presenting information in an auditory mode results in a higher level of road sign information recall, but also decreases the subjects' driving performance when compared to a visual display. Subjects were also able to recall more road sign information and drove at a higher level of performance during the filtered conditions. Subjects rated auditory information as more distracting than visual information.
Quantitative Evaluation of 4 Computer Keyboards: Wrist Posture and Typing Performance
Authors: Chen C. , Burastero S. , Tittiranonda P. , Hollerbach K. , Shih M. , Denhoy R.
Published: January 2012

The present study focuses on an ergonomic evaluation of 4 computer keyboards, based on a quantitative analysis of wrist posture and typing performance and on subjective analyses of operator comfort during typing. The objectives of this study are (1) to quantify differences in the wrist posture and in typing performance when the four different keyboards are used, and (2) to analyze the subjective preferences of the subjects for alternative keyboards compared to the standard flat keyboard.
Driver Performance Results from the Travtek IVHS Camera Car Evaluation Study
Authors: Dingus Thomas A. , Hulse Melissa C. , McGehee Daniel V. , Manakkal Raj
Published: January 2012

The TravTek system constitutes a major Intelligent Vehicle-Highway System (IVHS) Advanced Traveler Information System (ATIS) demonstration project. The system provided in-vehicle information via color touchscreen CRT, steering wheel buttons, and synthesized voice. The TravTek driver interface was developed with the intent of providing navigation, service and attractions, and roadway incident and traffic information to the driver. The design of the TravTek interface had as its primary objectives: (1) more effective driver navigation providing the benefit of saving time, (2) easy access to valuable and convenient location information to alleviate stress and increase driving enjoyment, (3) maintenance of safe driving performance during system use and safety improvement facilitated by information for avoiding hazards and for emergency response, and (4) improvement of roadway efficiency to alleviate congestion.

This paper provides detailed data regarding driver performance and behavioral interactions with four TravTek navigation configurations and two conventional methods of navigation: a paper map and a textual direction list. The results indicate that turn-by-turn information, regardless of its method of presentation, results in effective driving and navigation performance. A moving map display with no supplemental information required high visual attention relative to the other conditions. The other TravTek conditions resulted in lower workload superior navigation performance than the paper map control condition.
Test and Evaluation of Knowledge Transfer between Task Domains
Authors: Ye Nong , Brinkman Donald J.
Published: January 2012

To examine the transfer of knowledge representation between task domains, working engineers and pharmacists were asked to provide pairwise dissimilarity ratings of concepts in a test domain. The test domain was independent of engineering and pharmacy and was relatively new to both subject groups. A quantitative technique based on the multidimensional scaling and directional statistics was used to test and evaluate group differences in knowledge representation. The results indicated that there was no statistically significant difference between two groups in knowledge representation of the test domain. That is, knowledge representation was domain-specific and was not transferable between task domains.
Modeling Operational Criteria for Evaluating Speech Communication
Authors: Whitaker Leslie A. , Peters Leslie J.
Published: January 2012

Thesis: Evaluation of systems can be conducted best under controlled circumstances which approximate operational conditions. In the present paper, we have examined this thesis as it applies to the test and evaluation of multi-person systems. Our specific focus has been the development of a conceptual model of speech communication requirements and the study of the impact of degraded speech intelligibility on performance of these multi-person systems. To obtain the control necessary to evaluate performance using speech intelligibility, an electronic circuit was developed and employed in a series of simulated tests of operational tasks. The application of these research findings to the task of system test and evaluation is described in the present paper.
Learning and Transfer of Spatial Knowledge in a Virtual Environment
Authors: Bailey John H. , Witmer Bob G.
Published: January 2012

Two experiments were conducted to investigate route and configurational knowledge acquisition in a virtual environment (VE). The results indicate that route knowledge can be acquired in a VE and that it transfers to the real world. Furthermore, although it was not explicitly trained, participants acquired some configurational knowledge. Higher levels of interactive exposure to the VE resulted in better route knowledge than less interactive exposure. There was some evidence that more reported presence was correlated with better performance on spatial knowledge tests, while more reported simulator sickness was correlated with worse performance. Finally, performance during VE rehearsals was a strong, consistent correlate of performance on spatial knowledge tests.
Fidelity and Interactivity in Navigational Training: A Comparison of Three Methods
Authors: Williams Henry P. , Wickens Christopher D. , Hutchinson Scott
Published: January 2012

In two experiments we vary the degree of fidelity of a navigational training environment, and determine how this variance effects the degree of route knowledge and survey knowledge demonstrated in a navigational transfer task. Subjects learn about the geography of a computer-generated world by either (a) studying a 2D map of the world, (b) passively viewing a 3D course through the world on an IRIS display, or (c) actively flying through an IRIS-based simulation of the world. Groups (b) and (c) were yoked. All groups then transferred to a flight along the studied route plan in a high fidelity Evans and Sutherland visual simulation system. In Experiment 1, 60 pilots were assigned to the three training conditions, and the subjects in the two IRIS flight groups were subdivided into categories of low and high visual fidelity of the IRIS world. In this experiment, the active flight training condition yielded most accurate navigation performance (route knowledge), with the map-study group being nearly as proficient, and the passive group much lower. The map-study group had the highest recall of the geography (survey knowledge), but this knowledge did not provide them with any benefit in solving an unexpected navigational problem (functional survey knowledge). Visual fidelity had no effect on any measure of transfer performance. In Experiment 2, the speed and workload of the rehearsal flight was increased, and 10 pilots were assigned to each training group. The results revealed that the increased workload reversed the order of the two computer flight groups, with subjects in the active group who needed to rotate the map, now performing most poorly. The results of both experiments are discussed in terms of the detrimental effects of high workload to geographical learning, and to the dissociation between different kinds of geographical knowledge.
Learning Complex Visual Stimuli: Effects of Spaced Presentation and Rehearsal on Aircraft Recognition
Authors: Jarrard Stephen W. , Wogalter Michael S.
Published: January 2012

This study examined the effects of three presentation methods (one massed and two distributed) and two visual rehearsal conditions (rehearsal allowed and not allowed) on recognition of complex visual stimuli. The stimuli, photographs of military aircraft, were tested using a different view than the three views given at study. Recognition performance was measured by hit, false alarm, and discrimination indices to assess differences among the presentation and rehearsal conditions. A substantial effect of rehearsal was found. Allowing intervals for, and encouraging, post-exposure imaging increased hit and discrimination scores compared to conditions where post-exposure imaging was prevented. No significant effect of presentation method or interaction with rehearsal was noted. Exploratory analyses suggested that a study strategy involving attention to individual features to be associated with higher recognition performance. Empirical, theoretical, and applied implications of the study are discussed, and suggestions for further research are described.
Feedback and Team Training: Exploring the Issues
Authors: Blickensderfer Elizabeth L. , Cannon-Bowers Janis A. , Salas Eduardo
Published: January 2012

As team researchers have endeavored to understand team performance and team training, feedback in the team environment has been a neglected topic. A number of issues are involved in the design and provision of feedback to teams. These include team process/outcome issues in addition to characteristics of the task, team as a whole, and the team members as individuals. The inherent problems in team feedback provide the impetus for considering new approaches to team feedback. One such approach, team self-correction, may be valuable in clarifying anticipations and explanations among team members.
The Effects of Training on Cognitive Capacity Demands for Synthetic Speech
Authors: Gomez Catherine Connolly , Shebilske Wayne , Regian J. Wesley
Published: January 2012

Previous studies have revealed that the perception and comprehension of synthetic speech may be attributed to increased processing demands in short-term memory as reflected in serial-order and preload paradigm tasks. Additionally, it has been consistently shown that the perception of synthetic speech improves with moderate amounts of training. The present study was conducted to determine if the increased perceptual effects of training for synthetic speech can be attributed to a reduction of short-term memory load. Two groups of subjects were tested with synthetic speech using the same comprehension and high cognitive processing tasks before and after training. One group was trained with synthetic speech and the other group acted as the control, receiving no training between the pretest and post-test interval. Results reveal similar increases in comprehension based on previous synthetic speech studies for the trained group. Moreover, these results suggest that training on synthetic speech promotes better allocation of attentional resources which result in improved performance on working memory capacity measures.
The Effects of Workload and Uncertainty on Team Development
Authors: Urban Julie M. , Bowers Clint A. , Morgan Ben B. , Maniam Nalini
Published: January 2012

Two studies were performed that attempted to test and extend the team development theory of “punctuated equilibrium” proposed by Gersick (1988). In the first study, twelve five-person teams performed a resource allocation task, either under low or high workload. In the second study, twelve three-person teams performed an adapted version of this resource allocation task under either certain or uncertain task conditions. Various aspects of performance were assessed. The results of these studies support Gersick's contention that teams do go through one marked period of transition. However, this transition does not necessarily occur in the midpoint of the team's life cycle.
Development of a Real-Time Simulation with Intelligent Tutoring Capabilities
Authors: Gordon Sallie E. , Babbitt Bettina A. , Bell Herbert H. , Sorensen H. Barbara
Published: January 2012

Training programs for complex tasks are increasingly using simulations to provide transfer of training to the job environment without incurring high costs of on-the-job training. A second trend in training is toward the use of intelligent tutoring systems (ITSs) to provide individualized feedback to optimize training. Combining simulation with an ITS can be especially beneficial, but use of intelligent tutoring mechanisms such as expert systems is often difficult in a complex, realtime environment. In this paper, we describe the development of a proof-of-concept training program that combines F-16 flight simulation with an embedded real-time intelligent tutoring system. In the simulation, pilots learn the correct use of advanced fire control radar modes to locate and assess multiple enemy formations (search and sort tasks). The expert system monitors pilot behavior and verbal responses as the pilot flies the simulation. At certain critical points, if the pilot's performance has fallen outside of pre-specified parameters of “safe” behavior, the tutoring component stops the simulation and feedback is provided.
Visual Lobe and Visual Search Performance
Authors: Gramopadhye Anand K. , Sreenivasan Rakesh
Published: January 2012

Visual lobe continues to be an important determinant of extended search performance. This study looks at the effect of various methods of training on visual lobe size. Furthermore, it relates changes in visual lobe size to improvements in visual search performance. Subjects were trained using three different methods. In method 1 subjects were trained on a visual lobe improvement task using the actual fault. In method 2 subjects were trained on an irrelevant target using the visual lobe measurement task and in method 3 subjects were provided practice on the extended visual search task. Greatest improvements in lobe size and search performance were observed for method 1.
Effects of Perceptual Augmentation of Visual Displays: Dissociation of Performance and Situational Awareness
Authors: Shively R. Jay , Goodman Allen D.
Published: January 2012

It is intuitive that good performance is associated with, if not caused by, good situational awareness. There are, however, some situations in which these two concepts diverge. Some examples of this dissociation, such as auto-pilots, have been identified. However, it is also possible that these concepts diverge in a much more subtle manner. This research is focused on investigating those more subtle situations. Specifically, this research addresses the effects of perceptual display enhancement based upon Ecological Task Analysis (ETA) on performance and situational awareness. A perceptually augmented display was designed based upon ETA. Globally, performance advantages were found for the group with the enhanced display. Further, the findings demonstrated a dissociation of subtask performance and operator's knowledge of the system subtask. The mechanisms involved in this dissociation are related to the characteristics of the display augmentation that led to the increased performance. The level of processing, and the presence of feedback seem to play an important mediating role. These findings have important implications for both designers and researchers.
Dynamic Memory: Keeping Track of Continually Changing Information
Authors: Venturino Michael , Romano Nathan J. , Miller Sheryl L. , Murphy Megan , Coffey Tara M.
Published: January 2012

The requirement to remember continuously changing information places substantial demands on the human operator's working memory system. Previous research (Yntema & Mueser, 1960) found that in keeping track of dynamically changing information, humans' memory for changing information was better when they kept track of many different attributes of a single object than when they kept track of the identical attribute of many different objects. Due to a confound in the Yntema and Mueser experiment, the unique and combined effects of information organization and similarity-based interference cannot be determined, limiting the information about dynamic memory. This experiment represents an attempt to overcome this limitation by assessing the roles of organization and similarity-based interference in dynamic memory. The experimental task was a keeping track task in which a series of changing attribute values were presented sequentially, and subjects were required to remember the most recent update for each attribute. Three factors were manipulated in the experiment: number of “objects” (one vs many objects), type of attribute (same vs different), and memory load (2, 4, or 6 attributes to remember). Results showed that as memory load increased, keeping track performance in the many-object condition decreased to a greater extent than in the one-object condition. Also, as memory load increased, accuracy decreased at a greater rate for the same-attribute condition than for the different-attribute condition. The effect size for attribute similarity was much larger than that for number of objects. It was concluded that similarity-based interference is quite destructive to dynamic memory. It appears that the cost of attribute similarity far outweighs the benefits of organizing the continually-changing attributes. Such results have implications for structuring tasks and aiding memory in situations where operators must remember information in dynamically changing environments.
Evaluation of Alternative Methods of Representing Three-Dimensional Objects on Computer Displays
Authors: Wiebe Eric N.
Published: January 2012

Due to the increased use of 3D modeling software in the design and manufacture of products, careful evaluation needs to be made as to how the 3D model is represented on the computer display. The experiment's hypothesis is that both rate in which projections of a rotating object are presented and whether the object is rendered as a line drawing or shaded will effect the mental representation of the object. The experiment factorially crossed three levels of projection presentation rate with two levels of rendering (line drawing vs. shaded). All levels of both independent variables were between subjects. The subjects' score on a mental rotations test score was used as a covariant. The subjects each viewed 40 displays representing different rotating objects and identified the objects through a forced choice pair selection. RT and error rate were measured for each selection trial. Data on a total of 72 subjects was analyzed using the ANOVA procedure. The results of the experiment showed a significant main effect of the rate of presentation variable on RT. The results also showed a significant main effect of the rendering variable on error rate. No interaction was found between the two independent variables. The results indicate varying presentation rate can be an effective tool in allowing faster interpretations of an object. It is also recommended that the display technique be carefully matched to the complexity of the object being displayed and the capabilities of the computer being used to display it.
A Comparison of Two Head up Display Formats Used to Fly Curved Instrument Approaches
Authors: Reising John M. , Liggett Kristen K. , Solz Thomas J. , Hartsock David C.
Published: January 2012

With the advent of the Global Positioning System (GPS), pilots will be able to fly curved instrument approaches. Since current head up display (HUD) symbology was not specifically designed to present this curved information, a study was conducted to determine the most effective set of HUD symbology to assist pilots in flying curved approaches. The military standard HUD symbology was compared with the Pathway HUD format. Dependent measures collected for the comparison were root mean square (RMS) course deviations, RMS altitude deviations, and RMS airspeed deviations. Results showed that there was a significant difference in pilot performance for all dependent measures – subjects performed better using the Pathway HUD format than the standard HUD symbology in all cases. Pilots comments attributed the advantage of flying the Pathway HUD format to the fact that they could see their route in the form of a highway from their present position to a point 45 seconds into the future. This allowed them to anticipate necessary control movements.
Micro Saint Modeling of Visual Displays and Controls Consoles
Authors: Eisenhut Sandra M. , Beaton Robert J.
Published: January 2012

An experiment was conducted to evaluate the feasibility of using a predetermined time system (PTS) with the simulation model Micro SAINT as a method for making design decisions for a navy electronic interactive display and control console. Prototypes for different configurations were created using a Macintosh workstation. Configurations varied across two levels of symbol set, color condition, and screen format for three different target density scenarios. A Micro SAINT simulation model, emulating a single integrated task performed by the operator for all 24 prototype configurations, was constructed. The model was validated by regressing predicted performance scores on actual performance scores obtained from six subjects operating the prototypes. The model also successfully predicted the performance of a second group of six subjects. Although the questions of how to acquire standard deviation data and task time distributions remain, the use of a PTS in network simulation modeling can provide objective data for console designs without incurring the high costs associated with actual prototype construction and testing.
Human Factors Issues in Night Airborne Mine Countermeasures Operations
Authors: Ruffner John W. , Tullos Richard E. , Muldoon Richard C.
Published: January 2012

The U. S. Navy's Airborne Mine Countermeasures (AMCM) mission, performed by the MH-53E helicopter, is characterized by long duration flight at low altitudes and low airspeeds over the water while towing a variety of devices. This mission imposes substantial demands on the pilots and mission crew. Because of its complexity and potential hazards, the AMCM mission is currently performed only during the daytime. The Navy identified a requirement to perform AMCM operations at night and sponsored research to investigate the system and procedural modifications required to accomplish night AMCM operations safely and effectively. This paper discusses the human factors issues identified as part of this research effort and provides specific examples from the AMCM mission environment. A thorough understanding of these issues and how they will impact night AMCM operations is essential for a successful transition from day to night operations.
The Benefits of Auditory Spatial Information in Visual Processing
Authors: Strybel Thomas Z.
Published: January 2012

Techniques for the production of externalized, “3-dimensional” sound images for acoustic signals presented via headphone were developed in the past decade. These 3-D sound systems simulate both interaural time and intensity cues, and cues based on the action of the pinnae on incoming sound sources (e.g. Wenzel, Wightman and Foster, 1988). It has been anticipated that these 3-D sound systems would be useful in the cockpit and other work settings because they provide a natural method directing an operator to some event in the environment. This symposium is a progress report on research which has either examined potential applications of 3-D sound systems in the workplace, or attempted to understand how auditory spatial cues direct visual attention. Researchers at NASA Ames Research Center and Wright Patterson Air Force Base have identified cockpit tasks that can benefit from auditory spatial cueing. Some of these tasks include gate identification, blunder avoidance, and traffic identification of approaching and receding targets.

The benefits of audio spatial cueing are usually measured by determining the reduction in search latency that is realized when searching for targets with and without auditory spatial cues. These benefits can be explained by the findings that both simple detection and identification times are faster and more constant across the frontal hemifield when auditory spatial cues are presented with the target. Furthermore, for sounds presented in the central visual field, auditory spatial cues can either supplement or substitute for abrupt visual onsets in directing visual attention.
Age Differences in Perception of Workload for a Computer Task
Authors: Czaja Sara J. , Sharit Joseph , Nair Sankaran N.
Published: January 2012

Research concerned with age and work activities is an important area of investigation since the workforce is aging and there are concerns regarding economic dependency as well as labor shortages for certain occupations. Previous work by the research team indicated age differences in the performance and perceptions of task difficulty and fatigue for three simulated real-world computer tasks. This study is an extension of that research and is investigating the extent to which age differences in performance and perceptions of workload are moderated by experience and task practice. One hundred and twenty subjects aged 25 yrs. to 75 yrs. performed a real-world data entry task. Data will be presented regarding age differences in the perception of workload, stress, discomfort, and attitudes towards computers. The implications of these results for design interventions will be discussed.
Design of a Touch Screen Microwave Oven for Older Consumers
Authors: Loring Beth A.
Published: January 2012

The purpose of this study was to add to the knowledge of older consumers and their use of electronic products. The work involved redesigning a microwave oven by employing a touch screen interface. This provided a simpler panel with limited choices, step-by-step prompts and larger controls and displays. The design was tested for usability with 8 people over 60 and 8 under 60, in comparison to an existing microwave oven. Participants of all ages completed 4 out of 5 sample tasks faster with the touch screen model. The touch screen model was rated easier to learn and use on all tasks. This paper discusses the redesign of the microwave, the usability test, and final design recommendations.
Distribution of Discretionary Time by Retired People
Authors: Modrick John A. , Meyers Susan , Papke Robert
Published: January 2012

This study is a survey of the activities of retirees of a Fortune 500 manufacturing company. The objective was to provide a baseline description of activities as people adjust to changes associated with retirement and decremental changes of aging. A sample of 40 retirees was interviewed to obtain information on 1) demographics, living conditions, and health; 2) distribution of time over activities of work, recreation, family, and volunteering; 3) changes associated with aging and socio-economic factors. It is intended to provide an activity picture that will be a context for identifying behavioral problems and devices, organizations, and supporting aids to enhance quality of life.

Respondents represent the gamut of occupations and skill levels, socio-economic conditions, and ethnic diversity characteristics of a large, midwestern manufacturing corporation. The distribution of ages in the retiree population and sample were equivalent The activities surveyed include reading, watching television, household chores and maintenance, skill or craft hobbies, intentional exercise, care-giving, volunteer work, and work for pay. Analyses include differences and changes in activities as a function of gender, age, length of retirement, health, and living situation. Volunteer work is analyzed in detail concerning type, location of the work, and time spent on it.
On the Reproduction of Motion Parallax in Videocommunications
Authors: Böcker Martin , Runde Detlef , Mühlbach Lothar
Published: January 2012

The paper addresses the question whether reproducing motion parallax increases the extent of telepresence in videocommunications. Motion parallax is defined as the change of the view due to the observer's movements. It was hypothesized that reproducing motion parallax (a) leads to more precise depth judgments by providing further depth cues, (b) allows ‘interactive viewing’, i.e. the observer can actively explore the visual scene by changing his/her position, and (c) compensates for stereoscopic “apparent movements”. In a Human Factors study, two videoconferencing set-ups providing motion parallax (one stereoscopic and one monoscopic version) were compared with two set-ups (monoscopic and stereoscopic) without motion parallax. Each set-up was used and rated by 32 subjects. The results supported the hypotheses only in part. Even though there was some evidence for more “spatial presence” and for a greater explorability of the scene through motion parallax, the compensation of apparent movements could not be achieved.
Automatic Speech Recognition Applications: A Study of Methods for Defining Command Vocabularies
Authors: Garberg Roger B.
Published: January 2012

Phoneme-based automatic speech recognition (ASR) technology enables designers to easily create custom command words or phrases that users can employ to request service operations. In this paper, I report results from two experiments concerning important dimensions of these ASR command vocabularies, including command naturalness/appropriateness and command recallability. Ease of recall is a critical dimension for assessing ASR commands used in multi-step applications since service subscribers may be engaged in several different cognitive activities that divide attention. Yet techniques for measuring command recallability can be difficult to implement owing to the time required for data collection and analysis. Results of these studies indicate the the dimension of command “naturalness” and memorability are closely related: under appropriate conditions, the simple procedures associated with measuring command naturalness or appropriateness can predict retrievability of command expressions.
Using the Critiquing Approach to Cope with Brittle Expert Systems
Authors: Guerlain Stephanie
Published: January 2012

We have conducted a series of studies aimed at understanding how to design cooperative problem-solving systems to deal with situations in which the computer is not fully competent (the “brittleness” problem). Results from an initial empirical study showed that an expert system acting as an automated assistant induced new errors in such situations, but that this did not occur when the system was designed to critique user's performance on the task. Guided by these results, a more complete critiquing system was then designed and evaluated. On cases where the computer was fully competent, outcome errors were completely eliminated (a 30–60% reduction in errors). On a case for which the system was brittle (less than fully competent), misdiagnosis rates were still reduced by 31%, giving an overall significance of p < 0.000003 across all Post-Test Cases, further supporting our initial study regarding the potential value of critiquing as an effective role for an expert system. A detailed analysis of the influence of performance further indicates the ways in which different classes of critics detect errors and influence the user's problem-solving.