bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance Measures for Aircraft Carrier Landings as a Function of Aircraft Dynamics
Authors: Connelly Edward M.
Published: January 2012

A theory of performance measurement for operator controlled systems is presented. The theory permits synthesis of a system performance measure which scores performance on successive data samples based on the impact of the sampled performance on the overall summary of performance. Since performance is measured and evaluated on each sample, the dynamics of the controlled element, i.e., the aircraft, are effectively removed from the measurement eventhough the pilot (operator) continues to control the aircraft. While the theory directly applies to problems where the performance limiting factors are known, the method has been extended to apply to problems where the performance limiting factors are not known explicitly, but are known to be implicit in the performance data.

This paper documents the development of measures for aircraft carrier landings for the glide path and angle of attack control channels. Flight data obtained from the Visual Technology Research Center, Naval Training Equipment Center, Orlando, Florida, was analyzed using the measures. The data on carrier landings were available on 9-track magnetic tape consisting of flights by four subjects each performing on 42 flights. Each flight was performed on a particular combination of glide path error display and day/night combination. Two types of glide path displays were used, resulting in four treatments (two displays and two light conditions). One display was the conventional glide path display and the other was a command display which incorporates error rate information with glide path error presentation. Each subject controlled the aircraft to a carrier landing three times with each treatment.

The resulting performance scores were aggregated by subject, treatment, range to carrier deck, and error and error rate cells. The results suggest that the command display offers improved glide path control especially during day light conditions. Further, the measurement technique was shown to permit determination of the relationship between performance and factors that change during the flight - such as error and error rate magnitudes. The measurement technique bypasses the time delays due to aircraft dynamics - by accounting for them - permitting evaluation of performance on short (less than a second) intervals of flight. Consequently, observed differences in performance at different error and error rate magnitudes were detected suggesting that significant non-linear control techniques may have been exhibited by the pilots.
Evaluation of Mine-Safety Symbols
Authors: Collins Belinda L.
Published: January 2012

The effectiveness of safety symbols and hazard pictorials of mine-safety communication was determined in a multi-stage evaluation. The understandability of symbols for 40 messages and the perceived hazardousness of six different surround shapes were assessed. The effectiveness of a subset of 20 symbols was determined during an in-mine evaluation at two mines.
Development of a Human Factors Methodology for Nasa-Goddard Space Flight Center
Authors: Van Balen Paula M. , Mitchell Christine M.
Published: January 2012

NASA Goddard Space Flight Center, realizing the importance of the human-computer interface, has begun the process of integrating human factors considerations into system design. A methodology was needed to direct the process of incorporating human factors recommendations into the design process and to introduce human factors principles and procedures to Goddard projects. To gather necessary background information for an effective methodology, a diary was kept, recording the process of a Goddard human factors analysis. The diary technique was effective in identifying issues and steps relevant to the methodology. This paper describes and evaluates the diary as an information-gathering tool. Finally, the methodology is summarized and its effectiveness evaluated.
Human Factors Consulting Network (HFCN): Scope, Purpose, Ethics, and Goals
Authors: Jahns Dieter W.
Published: January 2012

Five distinguished co-moderators, familiar with the issues and topics of concern to Human Factors consultants, will help get the discussion started and address issues of special interest to each. The co-moderators and issues are:

Dr. Robert J. Cunitz

President

Consumer Usage Lab

Rockville, MD

Professional Ethics & Guidelines

Mr. George A. Peters

Attorney at Law

Santa Monica, CA

Professional Qualifications,

HF Legal Aspects, Litigation

Data Requirements

Mr. John H. Holly

Owner

John Holly & Company

Hawthorne, CA

Practice Management, Marketing, Public Relations

Dr. William D. Bliss

President

Human Factors, Inc.

Oregon, WI

HF Data Sources, R & A Techniques, Information Dissemination

Professor Earl L. Wiener

Prof. Mgmt. Science & Indus. Engineering

Coral Gables, FL

Consequences of HF Growth, “Forensic” vs. “Real” Consulting
Training Simulator Design for a Marine Engine Room at Different Levels of Fidelity
Authors: Govindaraj T. , Su Yuan-Liang
Published: January 2012

A marine powerplant on a large supertanker is a complex system made up of a number of interconnected subsystems where most functions are automated. A human operator manages the system in supervisory control mode, intervening only when an event occurs requiring his action to restore normal operations. For training marine engineering personnel to detect, diagnose, and compensate for failures, simulators at different fidelity levels are being developed. A low fidelity simulator uses information displayed on an Apple II computer terminal in conjunction with system schematics provided on paper. Details of the low fidelity simulator are described, and the results of a pilot experiment are discussed.
Factors Influencing the Logistical Support of Maintenance Training Simulators: The Development of a Handbook
Authors: Carroll Robert J.
Published: January 2012

Experience with maintenance training simulators has revealed a number of unanticipated logistical support problems. In some cases, the logistical support costs (i.e., the costs of operating, maintaining, and updating) incurred during the life cycle of the simulator have been greater than expected and sometimes have exceeded the initial acquisition cost of the device. Many of these costs were incurred because the personnel responsible for the acquisition of simulators were not aware of the factors influencing the life cycle costs or were not aware of the problems that could occur in operating, maintaining, and updating simulators. In addition, they had no systematic procedure for evaluating the logistical support needs of the maintenance simulators they were purchasing. This report describes the development of a handbook that addresses these problems by identifying factors which impact the logistical support requirements of maintenance trainers/simulators throughout their life cycle and providing a guide to help predict and plan for the logistical support required of a given simulator.
Design and Initial Evaluation of Mixed-Fidelity Courseware for Maintenance Training
Authors: Johnson William B. , Fath Janet L.
Published: January 2012

Results are reported of a project which involved the design of computer-based courseware for maintenance training. The courseware includes a training simulation which combines two levels of fidelity. The microprocessor-based courseware was developed for troubleshooting training on an electronic telephone switchboard at the U.S. Army Signal School in Fort Gordon, Georgia. Initial evaluation of the courseware demonstrated that computer-based simulation can be effectively used to supplement or partially replace “hands-on” practice with real equipment. Practice on the simulation, interspersed with real equipment practice, added a new and valuable dimension to the diagnostic training.
A Generic Model for Evaluating Team Performance
Authors: Hritz Rohn J. , Roth J. Thomas , Lewis Charles M. , Finley Dorothy L. , Dyer Jean L. , Strasel H. C.
Published: January 2012

The purpose of this paper is to discuss a model or methodology for evaluating the proficiency or performance of military teams. The methodology is appropriate for evaluating the performance of any team type performing any of its assigned mission. The methodology contains procedures for assessing both team process (team behavior) and team outcome (team success). Application of the methodology to a specific team performing a specific mission generates information which is useful in identifying team training deficiencies and in establishing team training requirements. The procedure is also useful for assessing the effects of team training, i.e., for measuring the amount and kind of team proficiency realized as a result of specific training.
Performance Evaluation Tests for Environmental Research (PETER): The Good, Bad, and Ugly
Authors: Bittner A. C. , Carter R. C. , Kennedy R. S. , Harbeson M. M. , Krause M.
Published: January 2012

The goal of the Performance Evaluation Tests for Environmental Research (PETER) Program was to identify a set of measures of human cognitive, perceptual, and motor capabilities for use in the study of environmental and other time-course effects. Tasks were evaluated as suitable for repeated measures applications when their intertrial means, variances and correlations were well-behaved under constant baseline conditions. This report provides an evaluation of 112 test measures studied in the program. They are categorized into four groups based upon joint consideration of task stability and task definition. Thirty test measures were categorized as Good, 15 as Good-But-Redundant, 35 as Ugly (flawed), and 32 as Bad.
A Technology Forecasting and Assessment Method for Evaulating System Utility and Operator Workload
Authors: Eggleston Robert G. , Kulwicki Philip V.
Published: January 2012

In the context of system design, technology assessment often proceeds in a bottom-up fashion, beginning with an evaluation of individual candidate system technologies. Issues of technology integration and human factors considerations are not addressed until later in system development. This paper proposes the use of a top down approach to technology assessment. The top-down approach has the advantage of evaluating technologies along dimensions of system utility, as well as technical performance, and treating human factors early in conceptual design. A technology forecasting and assessment methodology is described wherein technologies can be evaluated quantitatively in terms of technical performance, system utility, and operator workload.
Ground Control Considerations for Remotely Piloted Spacecraft
Authors: Hartley Craig , Cwynar Dave , Ray Lex , Garcia Kathy
Published: January 2012

To augment the capabilities of the space transportation system, NASA has funded studies aimed at developing a reusable, remotely piloted spacecraft capable of delivering and retrieving payloads at altitudes and inclinations beyond the reach of the present Shuttle Orbiters. Development of such a remotely piloted spacecraft involves five major categories of human factors design issues related to controllability: 1) mission conditions including thruster plume impingements and signal time delays; 2) vehicle performance variables including control authority, control harmony, minimum impulse, and cross coupling of accelerations; 3) maneuvering task requirements such as target distance and dynamics; 4) control parameters including various control modes and rate/displacement deadbands; and 5) display parameters involving camera placement and function, visual aids, and presentation of operational feedback from the spacecraft. To resolve these human factors design issues, the Martin Marietta Company is presently engaged in a program of research based on high fidelity simulations of remotely piloted spacecraft operations. Preliminary results of these studies will be presented in an interactive session at the 1984 Human Factors Society Annual Convention.
The Business of Human Factors
Authors: Malone Thomas B. , Malone Mary T. , Kirkpatrick Mark
Published: January 2012

This paper describes the implications of treating human factors as a business. It discusses what such a business has to sell, who it sells to, how it makes the sale, who provides the products and services, why the business is constituted, and how it must be managed to be successful. Clearly, a human factors business must be managed for the good of its customers, its employees, and its stockholders. Not as obvious, however, is the fact that it must also be managed for the good of the human factors profession.
A Computer-Based System for Workstation Design and Analysis
Authors: Butterbaugh Larry C. , McBride John K.
Published: January 2012

The Crew Systems Development Branch of the US Air Force Wright Aeronautical Laboratories is pursuing a system of computer-aided design and evaluation techniques (CADETs) for aircraft crew station development. Composed of individual computer-based human factors design tools and analysis methods, the system's key element is a user-interface module (UIM). The UIM serves as the single user-computer interface, through which all CADETs are accessed, eliminating many of the potential disadvantages normally associated with such an approach (e.g. diverse user backgrounds and varying user familiarity with computers). The CADETs are being implemented in a modular architecture to permit easy upgrade, replacement, or addition of any design tool or analysis technique. These features, and others discussed herein, are being combined to produce a system with numerous desirable attributes including user friendliness and software portability. A powerful, effective CADET system will result, employing computer graphic, analytic, and data base technologies for the design of workstation layouts, and the analysis of workstation geometry, man-machine function allocation, and operator workload.
Wrist Twisting Strength of four Year Olds: Product Packaging Implications
Authors: Rohles Frederick H. , Laviana Joseph E. , Moldrup Kelli
Published: January 2012

The research reported in this paper is the second of a two phase study related to consumer packaging. In the first phase, the subjects consisted of 100 elderly males and 100 elderly females. The results of this phase of the study were reported at the 1983 HFS meeting in Norfolk. In this phase of the study, the subjects were 100 four-year old boys and 100 four-year old girls. The purpose of the study was to measure their wrist-twisting strength or the torque that could be exerted on jar lids of various diameters. To accomplish this, a standard torque-wrench was modified so as to accept eight container lids whose diameters ranged from 27 mm to 123 mm. Each subject performed the wrist-twisting task on each lid four times - twice clockwise and twice counter-clockwise. Using torque as the dependent measure, analyses of variance were computed for the boys and girls separately. The results showed that direction of rotation - clockwise or counterclockwise, was not significant. However, lid as a source of variation was. When age, body weight, height, grasp, lateral prehension, and hand length, breadth, and spread were correlated with the wrist-twisting strength, it was found that for the boys, grasp was critical for all eight of the lids and hand length and spread were equally important. For the females, the individual's body weight plus grasp were significantly correlated with torque for all eight lids. And whereas age and weight were significantly correlated with the torque that could be exerted on seven of the eight lids for the girls, they were only modestly related to torque for the males. However, like the boys, hand spread was significantly correlated with torque among the females. Findings related to reports of the Consumer Products Safety Commission and the Safety in Packaging Act are discussed and a proposal is advanced suggesting that the use of containers whose lids have diameters of 60 mm and larger would be too large for a four-year old hand to open while they could be readily opened by the elderly consumer.*
The Borg Scale Validation for a Consumer Product - Automobile Polishes
Authors: Kreifeldt J. , Hill P. , Clarke M. M. , Draper J.
Published: January 2012

The Borg scale which is purported to correlate subjectively perceived heart rate with objective physiological workload was tested for its predictive utility by subjects using 5 different car wax formulations. Subjects applied and removed the waxes from a high gloss painted panel. The amount of effort and time expended with each wax were determined using a force platform and timing device. Subjects also gave a Borg scale numerical rating as they used each wax. The reported high correlation between Borg scale ratings and exercises using a bicycle ergometer, weight lifting, etc. suggested that it might be a reliable predictor of workload effort or time in such common tasks as car waxing.

Results indicate that the ability of the Borg values to predict either amount of time taken or effort expended was moderate (r =.58) on average, with a relatively high correlation between time and effort (r = .61). The rank orders of averages for Borg values and work effort, however, agreed well across the five waxes. Additionally, results clearly indicated superior performance (actual and perceived effort) of a newly formulated wax.
Re-Analysis of Morse Code Learning Data Using Structural Equation Models
Authors: MacKinnon David P.
Published: January 2012

The correlation matrix of 14 tests and the time to reach four levels of Morse code proficiency reported in Fleishman, Roberts and Friedman (1958) and Fleishman and Fruchter (1960) was analyzed using structural equation methodology. This methodology was not available at the time of the original research and is especially suited for the data in these studies. The method is based on the standard maximum-likelihood approach for parameter estimation and goodness of fit. Five factors were extracted from the correlation matrix of 14 tests. These factors were significantly correlated and differed only slightly from the factors obtained in the original factor analysis. The factors were auditory perceptual speed, auditory rhythm perception, speed of closure, visualization and verbal ability. The time to reach a level of proficiency on Morse code was significantly predicted by the time to reach the previous two proficiency levels. The Auditory Perceptual Speed factor was a significant predictor of Morse code learning to each of the four proficiency levels. A speed of closure factor significantly predicted learning to the second proficiency level. The visualization factor was a significant negative predictor of learning to the 2nd and 3rd proficiency levels. This result suggests that individuals who are high in visualization ability may adopt a visual strategy (such as visualizing dots and dashes) that is detrimental to performance at the middle learning levels. In contrast to the earlier findings, the auditory rhythm factor was unrelated to reaching any of the proficiency levels. Overall, the results demonstrate the usefulness of correlation structure models in the area of selection and training.
Human Factors and Performance Evaluations of the Emergency Response Information System
Authors: Casey Steven M. , Dick Robert A. , Allen C.C.
Published: January 2012

A human factors engineering review and a formal performance evaluation of the Emergency Response Information System (ERIS) were conducted at a full-scale Boiling Water Reactor simulator. The human factors engineering evaluation focused on display formats, display hardware, and user/system dialogues, and was based on previously-developed checklists. The formal performance evaluation was conducted during eight days of testing and review with nine operator trainees serving as plant operators. Each of three, 3-member crews participated in 16, 30-minute trials during which plant transients were simulated. Critical crew actions were monitored by five observers, and plant parameter data were gathered automatically. Subjective data on trial difficulty (with and without ERIS) and display effectiveness were obtained from operators. The overall results supported the hypothesis that ERIS was of benefit to operators during emergency conditions.
The Perception of Display Delays during Single and Multiple Keystroking
Authors: Boyle James M. , Lanzetta Thomas M.
Published: January 2012

Two separate experiments were run to determine the perceptual threshold for time delays between key entry and the appearance of a character, or characters, on a VDT display screen. For the single keystroke case, in which one character was entered and subjects indicated whether or not a delay occurred between key depression and character display, the threshold was 165 milliseconds. In the multiple keystroke experiment, strings of characters were entered while typists visually attended to a display screen. Delays remained fixed during a trial. For this case, the perceptual threshold was 100 milliseconds.
An Evaluation of Aviator Training Ability Requirements Scale Ratings
Authors: McAnulty D. Michael , Jones Dennis H.
Published: January 2012

The Ability Requirements Scales developed by Fleishman and his associates have been widely used as a job analysis technique. However, the ability ratings obtained with this technique may be confounded by rater bias effects. Fifteen instrument-phase instructor pilots rated the extent to which 32 basic abilities were required to perform 16 helicopter training tasks. Psychometric analyses showed significant differences in rater distributions. The method of successive intervals was used to transform the ratings to a common, equal-interval scale. Analyses of the transformed ratings indicate that significant task-ability discriminations were made that produced a logical, interpretable pattern of ability and task interrelationships.
Target Set Size, Time Sharing and Vigilance Performance
Authors: Hurts Charles M. , Halcomb Charles G.
Published: January 2012

The empirical literature describing the effect of number of signals (target set size) and number of signal sources to be monitored simultaneously (time sharing) on visual vigilance performance is reviewed. It is concluded that greater target sets and time sharing generally result in lower vigilance performance but that these effects are probably mediated through different information processing mechanisms. Moreover, the classical vigilance decrement was oftentimes found not to occur under time sharing conditions. A possible explanation of this phenomenon in information processing terms is offered. In order to test these generalizations a visual vigilance experiment was set up in which subjects had to monitor one or two dials for the occurrence of one or two kinds of critical signals. Results show that target set size had the expected deteriorating effect on hit rate and reaction time. However, time sharing only affected reaction time (longer) and did not interact with number of signals or time on task with respect to hit rate, sensitivity, false alarm rate or R:S ratio. The latter measures did not change over time. However, reaction times showed a signficant improvement (shorter) over time under time sharing conditions. In the discussion of these results issues like power of the design, learning effects, and signal conspicuity are addressed. Recommendations are given for future research.
Motorcycle Helmet Design
Authors: Berger Randall K. , Adams S. Keith
Published: January 2012

Extensive research and operational data have shown that a motorcycle helmet is very effective in reducing injuries resulting from a motorcycle accident. However, less than 50 percent of all motorcycle riders wear a helmet. Therefore, to encourage helmet wear and, thus, decrease critical injuries, the helmet must be designed with the wearer in mind.

A sample survey of 94 motorcycle riders was taken to rank various features of design. The data were compiled and statistically analyzed to determine the features that helmet wearers and non-wearers deem to be most critical.

With these features in mind, several helmets from a local motorcycle shop were carefully examined. Ergonomic parameters (padding thickness, field of view, etc.) of each helmet were recorded.

Utilizing the survey information and the measurements of current helmet design, an optimum helmet was developed.
Mine Safety, Productivity and Job Design
Authors: Whitaker Leslie A. , Shoptaugh Carol F.
Published: January 2012

Modern surface mine safety and productivity data were summarized as part of the Bureau of Mines Industrial Hazards/Human Factors program. Safety Information was obtained through mine site visits (observations and interviews), national actuarial statistics, tables, and MSHA accident reports. The examination of 148 accidents showed three specific contributing factors. First, mining is a rugged industry in which the environment is unstable and unpredictable. This unpredictability contributes to both accident incidence and severity. Second, large vehicles (120 ton haulpacks) move, fully loaded among small vehicles and people. This mismatch in size makes a collision a very severe accident. Finally, job design was found to be a contributing factor in accidents. Sixty-seven percent of the sampled accidents involved the misuse of a tool or procedure. These are not random errors, but reflect short cuts the workers take to save energy and increase productivity. It was proposed that correct job procedures would not be followed if the more efficient shortcuts were available. Consequently, the next step in this program is to develop modified job procedures for a few selected tasks. These procedures would be redesigned to improve efficiency and avoid the safety hazards found in the workers' make shift shortcuts. This approach changes the focus from emphasizing safety to emphasizing productivity through the design of safe and efficient job procedures.
Workvests (Lifevests) Used for Dredge Mining
Authors: Krohn Gregory S. , Sanders Mark S. , Peay James
Published: January 2012

This paper presents a study to develop an improved workvest (lifevest) for use on dredge mining operations. A prototype workvest having several innovative ergonomic and safety features was developed based on interviews with dredge workers. A series of three experiments was conducted to investigate the effects of workvest features on worker comfort and body movement. Later a field study was conducted in which workers wore the workvest for 30 days while performing tasks.
A Video Test for Prediction of Tank Commander Performance
Authors: Johnson Jimmie H. , Jones Marshall B. , Kennedy Robert S.
Published: January 2012

Two experiments were conducted to determine the utility of a microprocessor-based video test for the prediction of tank commander performance. A task analysis identified elements to serve as simulated job samples. Significant correlation coefficients were obtained between test performance and supervisory rankings, but were positive for two groups and negative for two groups. It was concluded that the predictive validity occurred by chance.
New Perspectives in Job and Organization Design
Authors: Brown Ogden , Griffin Ricky W. , Keller Robert T. , Hendrick Hal W. , Laughery Kenneth R.
Published: January 2012

Job and organization design are increasingly important variables when one takes into consideration the two key objectives sought by most organizations: organizational effectiveness (productivity) and member welfare (job satisfaction). Job design is most relevant at the microergonomic level where the focus is upon human-machine and work station factors. Organization design is, of course, more concerned with the macroergonomic aspects of systems and their structures. The panel will address both of these areas of interest, and will present different perspectives and new directions in both job and organization design.

Dr. Griffin, in his presentation entitled “Individual, Work-Related, and Social System Factors in Job Design/Redesign”, will discuss how a considerable amount of research over the last several years has demonstrated the complexities involved in how individuals develop their perceptions of their jobs and how they subsequently respond to their jobs. One category of variables which affects perceptions and reactions is the individual. Elements such as experiences, aspirations, and abilities all come into play. The work-related factors which have received the most attention include the objective job itself and the physical setting in which it is performed. Finally, social system variables such as the immediate work group, organizational culture, and occupational status also affect how people perceive and respond to their jobs. This portion of the discussion will summarize each of these perspectives, suggest avenues for potential integration, and identify major implications for organizations.

Dr. Hendrick will address the topic of systems design from the macroergonomic perspective. Dr. Keller will present design considerations from both micro- and macro-points of view. Dr. Laughery discuss design considerations as they relate to safety and accidents. Each participant will also address other design issues.

A discussion of some theoretical foundations of job and organization design will also be presented and current applications will be discussed. A model of job design will be put forth which includes current knowledge and components of managerial approaches to job design/redesign. The redesign of core job characteristic dimensions approach will also be discussed, as will the importance of need strength in job design. And finally, application of a sociotechnical systems approach to organization design is advocated so that organizations are designed to operate in the most effective possible way to achieve increased organizational effectiveness and quality of work life through an integration and joint optimization of psychosocial, cultural, and technological factors with human-machine performance interface factors.
A Preliminary Flight Evaluation of the Peripheral Vision Display Using the Nt-33A Aircraft
Authors: Gawron Valerie , Knotts Louis
Published: January 2012

The Malcolm Horizon, a Peripheral Vision Display (PVD), was installed in the NT-33A variable stability research aircraft to provide the evaluation pilot with a gyro-stabilized horizon line of red laser light. An experiment was conducted to determine the effect of the PVD on pilot workload. Workload was inferred from performance on a secondary task, in this case the Sternberg task, generated by the Workload Assessment Device (WAD). The primary task required the pilot to maintain airspeed, altitude, and angle of bank during instrument flight conditions. Nine NT-33A flights were flown by two evaluation pilots. Presence of the PVD reduced the WAD reaction times of one of the pilots; the reaction times of the other pilot showed mixed results. Recommendations for future research are presented.
The Effect of Time in the Psychophysical Study of the Maximum Acceptable Amounts of Liquid Lifted by Females
Authors: Karwowski Waldemar , Yates J.w.
Published: January 2012

The determination of the maximum acceptable weight of lifting using the psychophysical method was examined over a four hour period. Six females lifted a standard milk carton case from the floor to a height of 0.79 m. The subjects chose the amounts of liquid acceptable to them by instructing a helper to increase or decrease the weight of the case. The amount of liquid acceptable to subjects at 4 lifts/min after four hours of lifting was not different from the weight estimated by them after 20 minutes. However, at 8 lifts/min the acceptable amount of liquid decreased with time. These results suggest that a 20 minute period may be sufficient to estimate the maximum acceptable weight for the frequency of 4 lifts/min, but not for the frequency of 8 lifts/min.
Handle Positions and Angles in a Dynamic Lifting Task
Authors: Drury Colin G. , Deeb J.M.
Published: January 2012

Thirty industrial subjects took part in a manual lifting task, using different handle positions on a container and different angles between handle and container. Lifts were from floor to waist, waist to shoulder and floor to shoulder. Upper extremity body angles were measured, with heart rate and rated perceived exertion. As in previous static holding experiments, it was found that handle positions with both horizontal and vertical stability gave good results. As a result of this work, handle positions are recommended in the middle of the front edge of a box (at 60°) and in the middle of the lower edge (at 50°). Such an arrangement will minimize wrist deviation and slippage angle between handle and hand.
Biomechanical Evaluation of Selected Manual Materials Handling Activities of Railroad Workers
Authors: McMahan Paul B.
Published: January 2012

The historical development of back compression and muscle strength modeling is reviewed. A microcomputer version of these models was developed. Examples are given to demonstrate the applicability of these models in the analysis and design of railroad jobs.
Human Factors in Medical Rehabilitation: Some Major Problem Areas
Authors: Corso John F.
Published: January 2012

Medical rehabilitation is a rapidly growing field in which the discipline of human factors can make substantial contributions. Some of the major problem areas include the development of a taxonomy of activities of daily living, the design and evaluation of orthotic and prosthetic devices including environmental control systems, and the structuring of effective rehabilitation training programs. Specialists in human factors should recognize the impact of their potential assistance in medical rehabilitation and should be encouraged to meet this challenge.
Manual versus Robotic Assembly: Some Implications of Product Design
Authors: Domas Karl , Helander Martin
Published: January 2012

In order to facilitate automatic assembly by robots, it is necessary to reduce the number of parts to be assembled. A recent study at IBM analyzed the assembly paper feeding device for a copying machine that was composed of 27 different parts. This was too much for an automatic assembly procedure. After redesigning the product, the number of parts was reduced to 14, 13 of which could be assembled by a robot. The remaining part had to be inserted by a human operator. Such redesign usually incorporates several principles which facilitate robotic assembly. For example, the use of symmetrical parts so that the robot does not have to turn parts around, the use of notches to guide the insertion of parts, and a reduction in the number of screws used. The surprising outcome was that although the product could now be assembled by a robot, manual assembly had also been considerably simplified. In fact, it was so easy that it didn't pay off to use a robot. This redesigned part is still assembled by human operators. Obviously, changes that make the process easier for a robot might also simplify manual assembly. It seems ironic that we know more about the needs of robots than humans. This paper will discuss two examples of product design for assembly by robots.
Improving Quality of Work Life through Effective Organizational Design and Management
Authors: Brown Ogden
Published: January 2012

Certain evolutionary changes are occuring within American industry which contain many implications for the ways in which organizations are managed and operated. The use of alternative management systems is one way to cope with these changes. The solution to human resources problems has become just as important as the introduction of new technologies and the generation of capital. A growing body of evidence seems to suggest that quality of work life (QWL) programs are appropriate interventions to enhance both organizational performance and quality of work life for the individual. Quality of work life programs are a key element in human resource management strategies of many major corporations. QWL as a concept will be defined, trends will be identified, and issues for the future will be raised. Case examples where quality and QWL are valued elements of organizational culture will be given where quality and QWL are treated as significant outcomes. Developmental and implementation aspects of a quality circle program will be presented along with lessons learned. A large scale joint union-management QWL effort will be discussed and significant features of this program will be identified. Empirically derived guidelines for implementation of QWL programs and the integration of QWL programs with supervisory training will also be addressed.
The Importance of Cognitive Style in Complex Decision Making
Authors: Kanter Mark F. , Coury Bruce G.
Published: January 2012

The notion of field dependence-field independence has been an important consideration in research assessing the impact of cognitive style on performance. The research reported in this paper assesses the importance of field dependence-field independence in a complex decision task requiring the subject to attend to multidimensional information. A simulated inspection task was chosen for this research because correct classification of faulty items was dependent upon the subject's ability to accurately weight the relative importance of each stimulus dimension. Twelve subjects were trained to classify simulated products into one of four quality control categories, and their scores on the embedded figures test was compared to their classification performance. The primary results of interest was the relative difference in classification accuracy between the two types of cognitive style. Field dependent subjects were hypothesized to be less accurate in classifying the simulated product since their cognitive style would prohibit them from ignoring irrelevant or less important stimulus dimensions. Subjects were also tested under conditions of increasingly severe time constraints in order to assess the interaction effects between cognitive style and mental workload demands. The results of this research will be discussed in terms of the importance of cognitive style and the implications of such individual strategies on decision making performance.
The Effects of Age Cohort, Job Family and Task Variety on Industrial Accidents Rates
Authors: Schmidt John K. , Petree Barry L.
Published: January 2012

The present study consisted of a multivariate analyses of approximately 3500 accident cases taken from a large petro-chemical complex outside of Houston, Texas. The accident reports were coded using a system similar to that recommenced by the National Safety Council, and from it frequencies and rates were generated for analyses. Log-linear analysis was conducted to test for age, job and task effects on accident rates as well as interactions between them. All models were found to be significant at P.05 level, indicating that age, job and task all have important impact in determining accident rates. The significance of the interactions show that age has a differential impact on the rate of accidents found within given jobs and tasks.
Human Factors Testing of Icons for PC JR'S Word Processor Application
Authors: Keller Arthur , Happ Alan J.
Published: January 2012

Problem: This paper describes a study which was done during the development of the PCjr's HomeWord word processor. The objective was to determine the extent to which menu icons were intuitively obvious.

Method: Study Phase 1: 24 IBM employees were tested. Half of the subjects with WP experience and half of those without WP experience were given 10–15 minutes of “training” (operational definitions). The test consisted of two blocks of trials separated by a 15 minute rest period during which a demographic questionnaire was given. Subjects observed the icons on the screen and then completed a matched-pair multiple choice test. Included in the choices was a false choice to minimize guessing. Subjects' confidence level and subjective responses were also obtained.

A confusion matrix was developed to identify which choices were made for each icon. Those icons which fell below a 90% correct identification cut-off were analyzed further. The Fisher Exact Probability Test was used to determine whether the correct selection of an icon and its function was dependent upon WP experience or the abbreviated “training”. Comments of the subjects were categorized and tabulated.

Study Phase 2: 31 dependents of IBM employees, aged 8–18, were tested with icons representing a subset of basic WP tasks. The test design was the same as that for adult testing except that (1) all subjects were trained and tested in the same way, (2) training was more extensive, (3) no false choice was in the test instrument, and (4) confidence level data was eliminated after the pilot test.

The test data were analyzed as for the adult testing except that (1) no confidence level data was used, and (2) a regression line was fit to identify icons vs. age. Comparisons were also made between test data for adults vs. minors.

Results: Major results indicated that displaying all icons in a menu enhanced learning; the original design of several critical icons, e.g., Save Document vs. Delete Document, were confusing; and effective learning of the icons began at about 10 years of age.

Conclusion: The improved icon designs added significantly to the salability of the product by eliminating confusing menu icons.

Acknowledgement: This is to acknowledge the support of Mr. J. Lewis in the analysis and reporting for Study Phase 1.
Effects of Several System Parameters on the 3-D Viewing of Static and Moving Stimuli
Authors: Horst Richard L. , LeCocq Andrew D. , Girard F. Pascal
Published: January 2012

By displaying slightly disparate video images of a scene separately to each eye, three-dimensional (3-D) viewing systems provide depth cues in addition to those that are available with 2-D viewing. Unfortunately, significant performance advantages with 3-D viewing have only sometimes been realized. There is evidence of a performance advantage with 3-D viewing in remote manipulation tasks, in which the cameras view the remote scene from a stable position. However, there is little information available on other tasks that involve the viewing of moving stimuli.

Many teleoperation applications involve the viewing of scenes in which movement occurs, either because objects in the remote environment are dynamic or because the cameras move through space on a mobile robotic platform. The purpose of the present research is to experimentally examine the interactions between selected 3-D viewing system parameters and the ability to perceive depth with static and moving stimuli. The results will provide basic data on the extent to which static and moving stimuli require similar adjustments of a 3-D viewing system in order to produce optimal performance.

Subjects viewed video-taped scenes in which two flat, rectangular targets appeared. One target was oriented vertically; the other was oriented horizontally. Subjects were asked to judge the extent to which the targets were aligned or offset in depth. The targets were presented at a range of actual offsets. In some conditions both targets were static, while in other conditions the horizontal target moved in a plane perpendicular to the cameras. Lighting, size and linear perspective cues to depth were controlled so that the depth judgements had to be made on the basis of retinal disparity.

Subjects' accuracy of judging small differences in depth, at three different target-to-camera distances, was determined as two viewing system parameters were manipulated. Optical base (i.e., the separation of the cameras) and convergence of the cameras was varied independently. Of interest was both the levels of accuracy that can be attained with static versus moving stimuli and any differences in the combination of optical base and convergence that lead to optimal performance with static versus moving stimuli.

The data collected here will prove useful in the development of a remote viewing system that, like human binocular vision, can dynamically change optical base and convergence as appropriate for the scene being viewed. Such a system should improve the operator's sense of telepresence in remote environments and thereby enhance the performance efficiency and operational safety of teleoperated systems.
A Digital Image Processing Facility for Human Factors Research
Authors: Kuperman Gilbert G. , Wallquist Donald L. , Katz Luan
Published: January 2012

Digital image processing system capabilities and methods offer the experimentalist creative opportunities for exercising precise control over image quality and content parameters in the creation of visual stimuli. The Human Engineering Division of the Air Force Aerospace Medical Research Laboratory (AFAMRL) has established the Visual Image Processing, Enhancement, and Reconstruction (VIPER) facility to identify, develop, and apply digital image processing techniques against a variety of Air Force research objectives. This paper describes the VIPER facility and explores several current and planned areas of application.
Ergcncmic Shovel Design
Authors: Freivalds A.
Published: January 2012

In spite of increased automation, there still is a need for ergonomically designed manual tools in the modern consumer and industrial environment. For example, many studies have examined the work physiology involved in shovelling but few have referred to the shovel design parameters needed to make the task more efficient. Thus the effects of such parameters as handle length and size and shape of blade, were examined on shovelling performance, energy expenditure and subjective ratings of perceived exertion. The results indicated the following recommendations in shovel design: a long tapered handle for efficient digging and shovelling, a square-point blade for shovelling, a round-point blade for digging, a large blade for low density materials and a small blade for high density materials.
Dynamic Measures of Potential Training Success
Authors: Pitts Elizabeth W. , Salas Eduardo , Terranova Michele , Allen Gary L. , Morgan Ben B.
Published: January 2012

The Armed Forces and other large organizations often use scores from standardized aptitude batteries as indicators of cognitive aptitude. However, aptitude may also be demonstrated by the learning that occurs during training and measured by parameters such as initial ability levels and time needed to acquire information or skills. By using computer administered Complex Experimental Learning Tasks (CELTs), learning rate parameters recently have proved to be pragmatic as well as theoretical indicators of final performance. Potential advantages of this approach include ease and economy of computer administration, testee acceptance of job relevant tests, and potential benefits of shortened training schedules. The current research compared rate measures derived from learning on four CELTs with a paper-and-pencil battery designed to include static aptitude measures of the same domains. Performance measures were computed from stimulus display times, subject response time, and item accuracy. Overall final performance was computed using the average of the last five minutes. Correlational analyses and regression indicate that, with some qualifications, learning rate measures are predictors of individual and overall levels of performance on each CELT. Implications of these findings are that the current practice of using static aptitude tests for selection to training programs may not provide the most accurate picture of an individual's potential success or failure in that program, and that, given the trend towrds new computer-assisted training technologies, individuals may be selected on the basis of their potential for rapid learning, thus making use of the least expensive and most efficient training methods possible.