bluuebunny/crossref_metadata_2025 huggingface dataset:
Retention of Helicopter Flight Skills: Is there a “Critical Period” for Proficiency Loss?
Authors: Ruffner John W. , Wick Daniel T. , Bickley William R.
Published: January 2012

This paper presents and discusses data on the proficiency loss of Army helicopter pilots following no-flying periods of one year or longer. On two separate occasions, a group of 24 Army Individual Ready Reserve (IRR) aviators were retrained on each of 37 contact flying tasks in the UH-1 helicopter. The first retraining occurred shortly after the aviators joined the IRR Aviator Training Program. At that time, the aviators had not engaged in active-duty flying for periods ranging from 2 to 12 years; the median duration of the no-flying was 9.3 years. All IRR aviators were retrained a second time—on the same 37 contact flying tasks—one year after completing the first retraining period. The primary dependent variable was aircraft hours required to achieve proficiency on all flying tasks. In addition, each aviator's proficiency on each flying task was rated at the beginning and at the end of each retraining period. The results show that, on the average, the number of flying hours that IRR aviators required to regain proficiency was 16.2 hours for the first training period and 13.8 for the second period. The number of flight hours required to retrain aviators was found to be inversely related to the total number of flying hours an aviator accumulated while on active duty. The ratings on pretraining checkrides showed that no aviator was proficient prior to either training period; however, proficiency was rated considerably less at the outset of the first training period than at the outset of the second. When considered together with the results of other recent research on flight proficiency loss, the results of this study suggest that there may be a “critical period” of no flying during which an operationally important loss of flight proficiency occurs.
A Computerized Quantitative Procedure for Modeling and Predicting Human Capabalities
Authors: Mital Anil
Published: January 2012

Equations, or models, which describe trends of experimental data are frequently used by ergonomists and human factors specialists to predict human capabilities. Advance knowledge of what people can do, or how they will respond to a set of conditions, permits efficient job and workplace design and safe matching of individuals with tasks. This paper describes a heuristic technique which can be used to model complex human responses. This relatively new method is more efficient than the traditional stepwise regression analysis and utilizes existing software for model development.
Simulation of Cart Pushing and Pulling
Authors: Lee Kwan S. , Chaffin Don B. , Herrin Gary D.
Published: January 2012

A dynamic biomechanical model is formulated for cart pushing and pulling. The model is used to simulate different task and human parameters to determine the potential effects of handle height, cart speed, body weight and the cart load that minimize slip potential during cart pushing or pulling. In addition, predicted vertebral column loadings as a function of task and subject parameters were also studied. Low handles were found to be better for pulling while high handles were better for pushing to reduce slip potential. As expected, a heavy person, combined with a light task force and a slow speed of movement proved to reduce the slip potential.
A Method for Relating Photometric Output of Daytime Running Lights and Accident Reduction
Authors: Kirkpatrick Mark , Bathurst James R. , Heasly Christopher C. , Perel Michael
Published: January 2012

In several studies (Allen and Clark, 1964; Cantilli, 1970; Andersson, Nilsson and Salusjarvi, 1976; Allen, 1979; Attwood, 1981; and Rumar, 1981) the use of daytime running lights as a conspicuity device has been demonstrated to reduce the frequency of certain classes of motor vehicle accidents. What has not been determined is a method to derive a functional relationship between photometric output of daytime running lights and accident rates. The authors discuss their approach in the development of a model for relating derived figures of merit (based on photometric measurements) of some 45 unique daytime running light units and accident rate.
Evaluation of a Questionnaire to Predict Adjustment to Shift Work
Authors: Courtright John F. , Frankenfeld Curtis A.
Published: January 2012

Folkard, Monk and Lobban (1979) proposed a questionnaire which offered promise to help distinguish between personnel who differ in the degree to which their circadian rhythms adjust to shift work schedules. Fourteen male and ten female subjects completed two versions of the questionnaire. A period of irregular shift work was interposed between the two administrations. Significant differences were found in the way the questions were answered on the two administrations. Factor analysis products were not consistent for the two administrations nor with the original scale.
Body Temperature and Information Processing Capability
Authors: Hancock P. A.
Published: January 2012

Typically, human performance is projected to fluctuate in a circadian manner, usually in association with body temperature rhythm. Such sinusoidal relationships are isomorphic in that they are, under most normal circumstances, phase-locked in environmental time. As body temperature rises so performance is improved. However, increase in temperature above the zenith does not result in increased capability. Rather, such elevation has the dual and opposing action of speeding performance while elevating error rate to produce an overall diminution of efficiency (e.g., Allan and Gibson, 1979; Nunneley, Reader, and Maldonado, 1982). It has been suggested that deep body temperature controls the speed of performance, while skin temperature mediates error through the control of comfort associated with peripheral variation. To overcome distress connected with peripheral increase, yet to utilize the superior speed elicited by alteration of central temperature change, the use of selective head heating has been explored. The present paper synthesizes data from selective heating studies and indicates the potential gains which may be realized in complex machine operation. Results from this paradigm have suggested facilitation in stimulus assimilation, decision making capability and response selection and execution (e.g., Hancock, 1983; Hancock and Dirkin, 1982; Holt and Brainard, 1976). This facilitation is not linear in temperature change. To a 1°C increase there appears a change in decision criterion such that individuals become more conservative in response. Above this threshold value, veridical gains in performance are manifest with a reduction in both task latency and error rate. Simple physiological accounts of such behavior are largely inadequate as the precise physiological effect has yet to be thoroughly documented. An initial outgrowth of this work is the potential usage of fluctuation in head temperature as a dynamic physiological reflection of imposed mental workload (e.g., Hancock, Meshkati, and Robertson, 1984). These performance facilitations under relatively slow temperature changes are contrasted with decrement observed under rapid temperature fluctuation. A potential relationship with the notion of attentional resource capacity is explored.
Revised Lifting Capability Data Base for the Industrial Workforce
Authors: Mital Anil
Published: January 2012

Several studies have utilized the psychophysical approach to generate lifting capability data for industrial workers. In all these studies, certain assumptions were made. These assumptions, as reported recently, are not valid and, therefore, lifting capability data based on the psychophysical approach must be subjected to certain adjustments. This paper reports new data on lifting capability of the industrial workforce and compares it with two previous studies. Data from all the three studies were adjusted for time duration and, since the three studies compared favorably, integrated to develop comprehensive lifting capability data bases. The effects of lifting frequency, box size, height of lift, and age of workers are discussed.
Evaluation of Three Testing Methods Used to Determine Cognitive Constructs in Computer Programming
Authors: Wallace F. Layne , Swigger Kathleen
Published: January 2012

Memorization has been an often-used technique for testing cognitive construct organization by programmers. This study looks at three different memorization techniques and introduces a new method for examination of syntax and logical constructs.
Computer Aided Design: Human Factors Considerations
Authors: Barfield Woodrow , Salvendy Gavriel
Published: January 2012

The following paper addresses the human factors considerations which affect the hardware, software, and human interface in a computer aided design (CAD) system. A table is produced which shows the allocation of taks and responsibilities for the human and computer in a CAD system. Future research directions for human involvement in a CAD system are discussed while an expert system for design tasks is proposed.
Human Supervisory Performance in Flexible Manufacturing Systems
Authors: Hwang Sheue-Ling , Salvendy Gavriel
Published: January 2012

The Flexible Manufacturing System (FMS) integrates humans, computers, robots, and computerized machines in order to meet system goals. The objective of this paper is to explore both the optimal allocation of tasks between human supervisor and computers and the optimal number of machines which a supervisor should control in an FMS. The hypotheses are proposed that there is an interaction effect between the number of machines and the task allocation level and that there exists an optimal level of number of machines for the operator to monitor. These hypotheses were tested in a statistically balanced experimental design using 30 subjects with three independent variables: number of machines (5 levels–4, 8, 12, 16, or 20 machines), task allocation (2 levels–high or low), and sequence of task presentation (2 levels). Physiological measures (EKG and respiratory rate) and two subjective stress questionnaires were used as indices of the arousal level. The results reveal that the Inverted-U function for response time as a function of machine level was not supported and the allocation level was significant for both performance and subjective stress criteria. These results suggest that in the supervision of FMS the task allocation to the supervisor is critical but that the size of the FMS system (4 to 20 machines), with the allocations studied, has no effect on either stress or performance of the operator in the FMS.
Longitudinal Study of a Distributed System
Authors: Eberts Ray , MacMillan Allen
Published: January 2012

A possible solution for decreasing the load on a centralized computer system is to distribute the load by incorporating personal computers into the system. The personal computers can either be used as smart terminals or as stand alone systems. This study investigates the human factors problems which could occur for such a distributed system. In the study, both faculty and clerical staff were provided with personal computers (the Apple Lisa, the Apple Macintosh, and the IBM PC/XT) which could be networied to a larger, centralized computer system. The errors, needs, and attitudes of the users were evaluated. Significant differences occurred between the two classes of users and between the three computer systems. Suggestions for implementing a distributed system, based upon the results of this study, are provided.
Army Hardman: Its Origin, Evaluation, Implementation to Date
Authors: Risser Daniel T. , Berger Patrick
Published: January 2012

The HARDMAN Comparability Methodology was developed by the Navy to estimate human resource requirements during the early phases of weapon system development. The Army has modified the system to support its own needs in this area. Four real system applications in the Army and an evaluation by the Jet Propulsion Laboratory indicated that it is useful, useable, and reasonably credible, and provides a near-term solution to the Army s needs. An Army Guide is under development.
“Composite” Templates for Speech Recognition for Small Groups of Users
Authors: Rollins Ann M.
Published: January 2012

A laboratory experiment was done to test speech recognition accuracy when the template patterns, against which spoken utterances were matched, were generated by combining the speech of several different talkers. This allowed several different speakers to talk in rapid succession to the system without each having to load his or her patterns. In general, median word recognition accuracy decreased by a few percent with composite patterns. The amount of the decrease depended on the size and composition of the group. This was considered to be a tolerable decrease for some applications. As the experiment progressed, it became apparent that the more difficult problems were human factors issues related to error handling, vocabulary choice, user groups, etc. These are discussed.
The Effect of Hand Position on Motorcycle Brake Response Time
Authors: Hurt H.H. , Thorn D.R. , Hancock P.A.
Published: January 2012

The operation of a motorcycle relies upon the safe and effective use of hand controls for steering, acceleration and braking. The frequent involvement of motorcycles in traffic accidents appears to be related to the ineffective use of the hand control operating the front brake, which is the principal control for braking the motorcycle. An experiment was conducted to determine the benefits of training to position the hand upon the brake control in advance of the requirement of brake control usage. The results demonstrated a significant reduction in brake activation time with the amended hand position.
Motorcycle-Automobile Collision Prevention through Increased Motorcyclist Frontal Conspicuity
Authors: Hurt H.H. , Hancock P.A. , Thorn D.R.
Published: January 2012

The majority of motorcycle-automobile collisions are the result of a violation of the motorcyclist's right-of-way by the automobile driver. The predominating cause of the multiple vehicle collision is a failure of the automobile driver to detect the presence of the motorcyclist in traffic when a traffic conflict develops. Such detection failures are associated with low conspicuity for the motorcyclist, and effective countermeasures have been investigated and applied to reduce accident involvement of motorcycles. However, comparable investigations of culpable automobile drivers have not been done to distinguish the exact nature of these detection failures.
A Classroom Training Revision Methodology
Authors: Carter Richard J.
Published: January 2012

A methodology was described to revise program deficiencies in Army classroom training identified during training effectiveness evaluations. The baseline for its design approach was discussed. The revision methdology's content and structure was presented in detail.
Computer Modeling of Human Performance on Microcomputers
Authors: Laughery K. Ronald
Published: January 2012

In the interactive session, a microcomputer version of the popular modeling language SAINT was demonstrated. This version, named Micro SAINT, offers an easy way of entering task networks and conducting computer simulations of human operators in systems. While more limited than the full version of SAINT, it is far more accessible and easier to use.

In this paper, a brief introduction of the concepts behind human operator modeling are provided. Also, the steps required to develop an operator model are briefly discussd.
A New Tilt on Computer Generated Space Situation Displays
Authors: Yorchak John P. , Allison James E. , Dodd Valor S.
Published: January 2012

Historically, map projection problems have been 2-dimensional. With air and space travel however, the need for accurate 3-dimensional projections has come about. This paper describes an experimental comparison of a fixed 2D projection and a user-defined 3D display for the depiction of satellite altitude and coverage area. Sixteen subjects completed 24 trials, 12 with each display orientation, which required them to make a True/False decision concerning a statement describing the altitude and coverage area of a particular satellite on the display. Reaction time (RT) and errors were collected and analyzed via separate ANOVAs.

The results of the study revealed that subjects preferred a “3D-looking” display, even though there was no significant difference between display orientations with respect to RT or errors. From research of this type we hope to produce user-oriented guidelines for future space situation displays.
Robot/Human Interaction: A Challenge for Job Design
Authors: Clarke Margaret M. , Kreifeldt John G.
Published: January 2012

This paper describes now a job involving robot/human interaction was designed to ensure a safe, efficient and productive workplace, and worker satisfaction with the human contribution to the job.

The job, which lasts about 4 hours, involves handling, sampling, dismantling, and visually inspecting containers of toxic materials. The job design was carried out in five phases.

1. Analysis of the requirements and hazards of each phase of the job and of the relative capabilities of the robot and of the human operator.

2. Allocation of tasks to the operator and the robot based on both the hazards involved and on the relative capabilities of each. All contact with the toxic materials and all tasks that could be preprogrammed were allocated to the robot. The operator was assigned all functions beyond the robot capabilities; for example, visual inspection for unknown debris and positioning fine alignments at locations that could not be predetermined. In addition, the operator will remain vigilant during all periods of robot activity, overseeing what the robot does and ready to take active control of the robot should it encounter anything beyond its scope.

3. Time study. A detailed time line analysis of the robot and human task sequence showed that human activity fell into three distinct peak periods with long periods of monitoring in between.

4. Workload estimation. One operator was estimated to be able to handle all human functions so that one operator per robot would comprise an efficient “team.”

5. Increasing operator vigilance. Operator boredom and inattention could be a very probable and potentially serious problem during the long monitoring. Operators might not be ready to actively enter the control loop to perform their pre-assigned alignment and visual inspection tasks. Or they might not notice the beginning of any possible robot mishap and might not take active control as soon as they should. Further steps were therefore taken in the job design to increase operator vigilance. First, a dynamic time display with appropriate auditory warning signals will give operators information about their approaching planned entry into the control loop. Second, it was assumed that operators' attention would wander and that the job should therefore be designed to make it easier for them to cognitively “find their way back.” Computer-generated graphics will therefore continuously display the robot's previous, present, and next major task steps in addition to the operator being able to see via closed-circuit TV what the robot is doing. Last, operator opinion will be sougnt and used for further ways to make the vigilance tasks less tedious and more meaningful to the operators themselves.
Inflight Evaluation of Four Measures of Pilot Workload
Authors: Hart Sandra G. , Hauser Jan R. , Lester Patrick T.
Published: January 2012

Four measures of pilot workload were tested in the NASA C-141 Kuiper Airborne Observatory. The measures included a communications analysis, subjective ratings of workload, subjective ratings of additional factors related to workload, and heart rate. Data were collected for 11 flights, each of which lasted approximately seven hours. Heart rate was found to be significantly higher for the pilot who was flying than for the pilots who was not flying and it varied significantly across flight segments, peaking during landing and take off, particularly for the pilot in the left seat who was responsible for aircraft control. For both left and right seats, the subjective assessment of stress rather than the subjective assessment of workload was significantly correlated with variation in heart rate. Frequencies of different types of communications varied significantly across segments of flight, however, they were not correlated with subjective ratings of workload. There was a significant difference between the left and right seats in the types of activities that contributed to their workload, however, workload was considered to be equivalent for the two
Effects of Posture, Load, and Rate of Carry on Task Heart Rates
Authors: Morrissey Stephen J.
Published: January 2012

Five well trained male subjects carried loads on a level surface with five levels of task weight, five levels of distance carried, five levels of rate of carriage, and in five task postures set between normal erect and stoopwalking under ceilings set at 80 percent of each subject's normal erect stature. The tasks were performed for 15 minutes, and heart rate measured during the last 5 minutes of task performance and averaged for the condition-subject value. Analysis of the resulting task heart rates found there to be little change due to the experimental conditions tested. Only in the most stooped postures and with the heaviest loads, did large (but not significant) differences in task heart rate appear. It was concluded that for the range of conditions examined, well trained male subjects were able to recover adequately in the period between the actual load carries.
Information Processing in Vigilance Performance: Complexity Revisited
Authors: Warm Joel S. , Dember William N. , Lanzetta Thomas M. , Bowers John C. , Lysaght Robert J.
Published: January 2012

Several experiments are described showing that the vigilance decrement can be reversed or retarded by a suitable level of complexity in symbolic functions needed for critical signal detection. This effect is most likely based upon motivational rather than learning factors and is dependent upon the selection of a complex task that is no more capacity demanding than a simple one.
User Strategies in Interactive Image Processing
Authors: Howard James H. , Shaw Raymond J. , Robertson Scott P. , Raver Jeffrey A.
Published: January 2012

Several related experiments are being conducted to investigate human performance in an image processing and interpretation task. In this task, users select operators from a set of image enhancement transformations in order to modify an image and facilitate interpretation. In several trials, subjects were required to identify images of ship hulls as belonging to one of four categories. Operator sequences, selection times, and categorization responses were recorded. Subjects adopted strategies that lead to the enhancement of spatial frequencies important for the categorization task. The strategies were easily identified, emerged in an orderly manner, and changed in predictable ways in response to changes in the frequency content of the task images. We are currently developing a production-based model to account for the operator sequences and selection times.
Lockheed In-House Human Factors Engineering Training Course
Authors: Parsons Stuart O.
Published: January 2012

A twenty week program of one hour a week training sessions for in-house personnel is nearing completion. The ourpose is to inculcate recent graduates with programmatic skills and to upgrade the skills of older human factors personnel. The course contains materials in three general areas, namely: 1) An overview of human factors functions at Lockheed, 2) the specific process and some examples, and 3) a description of other technologies and their relation to human factors.
Tactical Radio Communications Survey—A Pilot Study (Helcoms-PS)
Authors: Phelps Russell M
Published: January 2012

Voice radio traffic was collected at National Training Center exercises in Ft. Irwin, CA. The traffic consisted of five one-hour samples covering peak-period traffic on several command nets. This traffic underwent a detailed exploratory analysis and identified several human performance issues which will be subjected to further evaluation in a follow-on effort. Sample issues covered in this effort include expected wait time, transmission rates, station utilization factor, message categorization, interference, and dialogue patterns.
Structured Grading
Authors: Peacock Brian , Stewart Doug
Published: January 2012

This paper describes a compromise between the idealism of criterion based grading and the pragmatism of a norm based approach. The discussion is supported by a series of computer programs that are deliberately devoid of packaging clutter so that the users can clearly comprehend the processes and adapt the code to suit their particular purposes. The input data can be in numerical, alphabetical or categorical form and the primary output is a matrix of standardized marks. Additional analyses provide frequency distributions, rank order and alphabetic grade matrices, component correlations and categorical item analyses. The programs are designed to provide timely and appropriate information for final grade allocation.
The Development of two Dimensional General Population Manikins for Deriving Workstation Ergonomic Requirements
Authors: Church Russell , Phillips Mark
Published: January 2012

A unique approach which combined anthropometric data, human anatomical models, and artistic renderings was used to synthesize male and female manikin models representing the U.S. general population. The derivation of dimensions, joint locations and reach envelopes are discussed and scale drawings of the 5th percentile female and 15th percentile male manikins are presented. These manikins were used to derive console ergonomic requirements for next-generation air traffic controller workstations.
Thermography and Repetitive Stress Trauma: A Pilot Study
Authors: Riley Michael W. , Sanwick Robert T. , Cochran David J.
Published: January 2012

Liquid crystal thermograms were used in this pilot study to produce “surface temperature gradient maps” of the forearms, wrists, and hands of persons with and without symptoms of cumulative stress trauma. In addition, individuals with other common wrist and hand dysfunctions, impairments, or maladies such as arthritis were included to evaluate possible confounding factors in these procedures.

Bilateral comparisons were made of the thermograms of the upper extremities of each subject. Results indicate that temperature differences of 1 degree C. or greater between symmetric body parts, taken under correctly conducted procedures, may be interpreted as a positive indication of a definite and significant medical condition or trauma, including trauma produced by cumulative stress.
A Model for Estimating Maximal Aerobic Capacity
Authors: Tayyari Fariborz , Ramsey Jerry D.
Published: January 2012

A mathematical model, based on the information available in the literature, was developed which estimates the maximum aerobic capacity. It requires a submaximal pair of oxygen consumption and heart rate to obtain the maximum aerobic capacity of the subject (male or female). Its validity has been examined using Astrand-Astrand nomogram. The model is simple for use either manually or in computer programming.
Analyses of the Effects of two Individual Differences Classificaticn Models on Experiencing Mental Workload of a Comupter Generated Task: A Hew Perspective to Job Design and Task Analysis
Authors: Robertson Michelle M. , Meshkati Najm
Published: January 2012

Two individual differences classification models, Cognitive Complexity and Decision Style, were utilized to group participants for a mental workload experiment. All participants undertook four sequential phases of a simulated artillery command, computer generated, mental workload task. Measures of the mental workload were the subjective estimation of the relative task difficulty and the physiological response as reflected in the level of sinus arrhythmia. The abstract group was found to be significantly associated with the high conceptually complex decision styles; whereas the concrete group was related to the low conceptually complex decision styles. The abstract and conceptually complex decision style group subjective evaluation of task difficulty followed the progressive loading of the task. Conversely, the conrete and low conceptually complex decision style group perceived the initial phase of the task to be the most difficult. The sinus arrhythmia dependent variable demonstrated two different patterns for the unifocus and multifocus decisions styles. Implciations of the results of this investigation could be employed by managers in developing a more effective Job design approach and to optimized the job-person match. Further ramifications of the findings could contribute to efficient manpower planning and human resource utilization within the organization.
Computer-Based Instruction (CBI): Toward a User-Oriented Technology Data Base
Authors: Waldrop Grace P. , Lane Norman E.
Published: January 2012

A number of ongoing analyses and surveys are directed toward the development of a computerized data base on the capabilities and availability of CBI technologies in the Department of Defense. The process of providing such a data base goes far beyond the computerized storage of casually compiled data. This paper identifies and discusses two critical issues developed from a CBI research and development analysis in support of the CBI data base design. The first issue addresses the importance of specific attention to the characteristics and requirements of potential users both of CBI technology and of the data base. The second is concerned with the need for a well-conceived classification schema for description of the features of CBI systems in the form of data storage and retrieval cues. A preliminary schema is presented, and the impact of the two issues on the design and functioning of the data base is examined.
The Effect of Toeclips and Cleats on Bicycle Efficiency
Authors: McAnarney Daniel K. , Konz Stephan A.
Published: January 2012

The experiment had 7 experienced male cyclists pedal on a stationary bicycle at a 180 watt load for 10 minutes two, times under each of two conditions: control (no toeclips and no cleats) and test (toeclips and cleats). The criteria were heart rate, Borg vote, and a semantic-differential vote. Heart rate was 160.7 for the control condition and 161.3 for the test condition; the means were not significantly different. Borg vote was correlated significantly (r = .42) with measured pulse. The semantic-differential vote indicated a preference for cleats and toeclips.
The Precedence of Global Features in the Perception of Map Symbols
Authors: Knapp Beverly G.
Published: January 2012

This research was an investigation of how global processing of visual stimuli affect the speed and accuracy of map symbol perception in a search and locate task. It addresses the role of symbol structure in detection on maps, which is critical for prescribing how symbols should be designed and used. Symbols were scaled according to global and local features, and then detected as targets against a realistic map background. Globally and locally similar symbols were most distracting to each other as measured by response time, but not so for accuracy. The importance of local features for this type of task was the most critical finding.
User Interface Design for Maintenance/Troubleshooting Expert System
Authors: Koch Christopher G.
Published: January 2012

Expert systems applications for special environments impose special requirements on the user-system interface. A study was conducted to determine requirements and define a design concept for the interface for an expert system being developed to support corrective maintenance and troubleshooting of gas turbine electronic equipment and controls. The resulting design specifies a portable unit containing color flat panel video/graphics display, special function membrane keypad, miniature printer, and headset with voice input/output. Communication with the expert system is structured by multiple-window information presentation and voice-activated control functions.
Evaluation of a Video Storage System for Intrusion Detections
Authors: Chao Betty P.
Published: January 2012

The paper reports an evaluation of a video storage system used in conjunction with closed circuit televisions for surveillance purposes. When multiple intrusions occur simultaneously, video storage permits the user to assess intrusions that might otherwise be missed. A study of specific display characteristics was undertaken to optimize the effectiveness of the video storage system.
Software Prototyping as a Human Factors Tool
Authors: Pfauth Mike , Hammer Ann , Fissel Jim
Published: January 2012

This paper discusses the tools that the Human Factors Center at Texas Instruments uses to analyze, design, and evaluate software products. These tools permit development of prototypes that are interactive and that provide on-Hne specifications to the software developers. The discussion indicates how we have applied these tools to a variety of projects.
A New Model for the Evaluation of Recovery from Sub-Maximal Static Loading
Authors: Milner N. , Corlett E.N.
Published: January 2012

Assessing safe limits for isometric exercise has required estimations of the forces involved. Where complex postures are of interest such measures are difficult and an alternative model is advanced. The model, developed from empirical data, predicts recovery from the Maximum Holding Time (MHT) of the posture and the observed Holding Time (HT). Further experimentation has shown the model to be repeatable and applicable to another, very different, complex posture.
Three Comparisons of Incandescent and Fluorescent: Color or Luninaire?
Authors: Bennett Corwin A. , Perecherla Anjiraju , Chowdhury Zahirul K. , Prabhakaran Ramachandran , Gettu Shyam N.
Published: January 2012

Three experiments using 132 subjects and two different scale models primarily tested the hypothesis that there is no difference in pleasantness when extraneous factors of luminaire size, shape and distribution were controlled. Subjects, who were not aware what the light color was nor that light color was being studied, found incandescent and fluorescent equally pleasant.

Much verbal comparison and comparison by selection of one or the other has been made of incandescent and fluorescent light. While in recent years even more efficient sources have replaced fluorescent, fluorescent has been used in place of incandescent in spaces where pleasantness has not been considered paramount. This has included many factories and stores, most schools and offices and some home spaces where utility is considered more important than aesthetics (like laundry rooms). The greater pleasantness of incandescent has been so “obvious” that hardly anyone - lay or lighting -has questioned the aesthetic superiority of incandescent. Thus, despite the energy crisis and increasing cost of electricity, most designers and users have clung to incandescent in aesthetic spaces.

In addition to light color installations and luminaries for these speces vary drastically.
Designing Warnings to be Read and Remembered
Authors: Rothstein Pamela R.
Published: January 2012

Three kinds of memory for on-product warnings were tested as a function of four variables in an applied laboratory setting. The three kinds of memory tested were recall of hazards, recall of the means to avoid an accident, and recall of the action to take in the event of an accident. The four variables investigated were message length, serial position, message format, and pre-questionning. Basic research findings were substantiated in that message length, message format, and pre-questionning did have an effect on subsequent recall. However, the findings were not always in the expected direction and the effects were far from robust. Suprisingly, no significant effects of serial position were found for any of the three recall measures. Encoding problems due to the nature of the experiment, prior knowledge of warning information, and interference are discussed as explanations for unexpected effects.
The Distortion of Visual Space as a Function of Motion: Implications for Vehicle Operators
Authors: Mullins Wayman C.
Published: January 2012

The purpose of this study was to explore a velocity dependent distortion of visual space which may influence the ability of vehicle operators to accurately judge the distance of objects in visual space. Two experiments were conducted in which observers were driven past (facing either frontward or rearward) pairs of wooden stakes (space between endpoints of stake pairs either filled or unfilled) and asked to judge the distance between endpoints. Results showed that observers greatly underestimated the distance between endpoints of stake pairs when the space between endpoints was unfilled versus filled. Also, underestimation was greatest when observers were facing forward. Results are discussed in terms of practical considerations.
Events that Trigger Disabling Back Pain among Nurses
Authors: Jensen Roger C.
Published: January 2012

Nurses experience more cases of disabling back injuries in relation to their population than most occupational groups. Patient handling is generally assumed to be the hazard which causes most of the problems. The sparse epidemiologic evidence to support this assumption is reviewed. New information about the proportion of work-related disabling back injuries reportedly triggered by patient handling is reported. Based on the present state of knowledge, derived from reports by nurses who have experienced back pain, it appears that among nurses about 38 to 46 percent of all back pain episodes and roughly 73 to 81 percent of their compensable back injuries are attributed to patient handling.
Integrating Participatory Ergonomics into an Organizational Culture: A Macroergoncmic Approach
Authors: Imada Andrew S.
Published: January 2012

This paper examines the role of technology in creating new customer demands, the need for organizational flexibility, and the importance of worker participation. Moreover, the increased competition, and consequently, the increased complexity of these new technologies will create even greater needs for macroergonomic concepts in designing future systems. Finally, it is argued that participatory ergonomics and the introduction of new technologies need to be incorporated into a coherent organizational culture.
Extended Testing of Machine and Self Pacing
Authors: Mahesri Hunaid , Bennett Corwin A.
Published: January 2012

A review of literature on machine pacing versus self pacing generally seems to favor self pacing. This literature primarily involves simple tasks with short cycle times and short performance times. In the present experiment the construction of electronic circuits generally took five minutes or longer each and was a fairly involved task with two-hour performance times. For the particular machine pacing rate chosen performance results were equivalent except hit (time) rate. This increased with machine pacing without an increase in perceived effort. It was concluded that a general conclusion regarding self or machine pacing is false and must be conditioned by the particulars of the task.
Rule-Based Analysis of Pilot Decisions
Authors: Lewis C. Michael
Published: January 2012

Rule identification is proposed as an alternative to parameter estimation in the analysis of human performanc data. The relation between the choice of language and identifiable consistencies is discussed. Advantages of production system models for the description of complex human behaviors are examined. Threats to validity posed by the use of flexible languages in data analysis are examined. Contrivedness, defined by Eilbert and Christensen 82) as, “ the tendency of a search procedure to uncover apparent patterns where none exist”, is advanced as the major inferential hazard to rule identification. A Monte Carlo significance testing procedure to deal with this threat is proposed. Nonparametric measures of relation, tau-b and PRE, are presented as appropriate performance measures for rule-based models. A rule-based analysis of data from an experiment (Palmer, 1983) involving pilot decisions in air traffic conflicts is presented. Identified rules indicate satisficing with respect to the secondary goal of maintaining a constant course. Reduction in dimensionality of utilized information led to errors for a subgroup of pilots.
Development of User Interface Guidelines for Multi-Functional, In-House-Developed Information Systems
Authors: Stoddard Mary L.
Published: January 2012

User interface guidelines were developed for Los Alamos National Laboratory information systems to satisfy several needs: (1) to provide users with consistency between systems, (2) to provide programmers with the tools that they needed to speed the development process, and (3) to distill existing knowledge in the literature regarding effective user system interface design and target it specifically to our hardware, software, applications, and user populations. The significance of the guidelines lies in the development and implementation processes used. The guidelines are flexible and subject to frequent revision, yet have resulted in a significant increase in consistency from subsystem to subsystem.
The Role of Event-Related Potentials in Human-Machine Applications
Authors: Warren Charles A. , Stern John A. , Eddy Douglas R. , Horst Richard L. , Kramer Arthur F. , Parasuraman Raja , Sanquist Thomas F. , Wilson Glenn F.
Published: January 2012

This paper has four aims: to provide a brief introduction to the topic; to indicate the consensus of the contributors concerning the nature and direction of the discussion; to characterize the contributors' attempts at understanding and forecasting some trends in event-related potential (ERP) research and applications, and, finally, to convey some degree of criticality regarding the papers to be presented.
Micro Saint: A Computer Simulation System Designed for Human Factors Engineers
Authors: Laughery K. Ronald , Drews Carl
Published: January 2012

A computer modeling system is being developed specifically for simulating human operator systems. Primary design goals of the system are that it require minimal training and be easy to use for the novice while still providing the experienced user with powerful modeling capabilities. The language, Micro SAINT, is discussed.
Color Naming as a Function of Stimulus Luminance, Angular Subtense, and Practice
Authors: Post David L. , Greene Frances A.
Published: January 2012

An experiment was performed to assess the color names that native Americans use to describe colors that can be generated on a color CRT. Twenty-eight circular stimuli, whose chromaticities covered the CRT's chromatic gamut, were presented at two luminances and two angular subtenses. Subjects responded to each stimulus by typing a freely chosen color name into a computer terminal. The names were then studied to evaluate the effects of luminance, angular subtense, and practice.
Performance Measures and Subjective Evaluations for Two Color Displays
Authors: Christensen Cristina , Baggen Edward A. , Snyder Harry L.
Published: January 2012

This study was conducted to evaluate task performance and subjective preference for two color displays with differing image generation technologies, the standard cathode ray tube shadow mask display and the newer liquid crystal/cathode ray tube display. Six subjects performed three different information processing tasks using each of the two color display technologies and expressed their display preference via evaluation questionnaires. Ambient illumination measurements were obtained to determine optimal conditions for each display. Performance data were obtained as errors per unit task quantity for each of the task types. Subjective evaluations consisted of 5-interval bipolar adjective scales and a forced choice rating. Parametric analyses of the performance measures indicated minor differences between the two display technologies, while nonparametric analyses of the subjective data indicated a preference for the liquid crystal display technology.
A Study on Psychophysics of Weight Holding in Hand
Authors: Nanthavanij S. , Deivanayagam S.
Published: January 2012

This paper describes a research study conducted to investigate the human perception of a weight held in hand. Twenty male subjects participated in the study. Subject was blindfolded and was asked to guess the weight of a bag placed over his upper extremity by the experimentor. The objectives were twofold; firstly, to determine the ability of the subject to correctly guess the weight and secondly, to determine whether the location of placement of weight along the forearm influences this ability. The results suggest a linear relationship between the actual weight and guessed weight in the range studied. Also the locations along the forearm did not result in any significant difference.
Effects of Visual Angle on Reading
Authors: Gould John D. , Grischkowsky Nancy
Published: January 2012

The accuracy and speed of proofreading was unaffected by a wide range of visual angle (at least 16–36 deg). Text on most computer displays and on 8–1/2 × 11 in. paper subtend visual angles within this range—even with typical variations in reading distance.
Characterization of Good Teleoperators: What Aptitudes, Interests, and Experience Correlate with Measures of Teleoperator Performance
Authors: Yorchak John P. , Hartley Craig S. , Hinman Elaine
Published: January 2012

Since teleoperation will be a required feature of future space systems, it will be necessary to select and train individuals to operate these remotely controlled manipulator systems. Training for this type of activity will be extremely time-consuming and costly; consequently, it would be advantageous to train only those individuals who are best-suited for the task. A study conducted at NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama, attempted to construct a selection instrument composed of aptitude tests and questionnaire items that could be used for identifying individuals with an aptitude for teleoperation. Seventeen engineers from MSFC were given a 16-item questionnaire and three psychological aptitude tests designed to measure basic intelligence and spatial abilities. The aptitude test scores and the questionnaire responses were then correlated with actual teleoperator performance. The results of a multiple regression analysis revealed that the eight predictor variables individually were not significant with respect to operator performance, but as a whole, the regression model accounted for 49 percent of subject variance on the criterion task.
Commentary on Human Factors Engineering in the USSR
Authors: Cacioppo Anthony J.
Published: January 2012

Early political-ideological constraints caused Soviet human factors engineering to have a difficult gestation; however, in recent years it has achieved a high degree of proficiency. This paper discusses the early development of human factors engineering in the USSR, describes the direction which human factors has taken, outlines analytic and engineering approaches employed, and delineates differences in professional philosophies between Western and Soviet practitioners.
Individual Differences in Criterion Task Set Performance
Authors: Gilliland Kirby , Schlegel Robert , Dannels Sharon
Published: January 2012

As part of a larger standardization study of the U.S. Air Force Criterion Task Set (CTS), a number of individual difference variables were assessed to evaluate their relationship to CTS performance. The selection of these individual difference variables was based on their known or hypothesized relationship to performance or perceptual abilities. This paper reports some of the preliminary findings with regard to these individual difference variables. Of the variables measured, Stimulus Screening, Thrill and Adventure Seeking, Neuroticism, Type–A Behavior, and General Intelligence showed the most promising relationships to CTS performance variables.