bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction on Ward 8: Physical Settings and Behavioral Change
Authors: Kleeman Walter , Hartford Barbara D. , Reeves Robert E.
Published: January 2012

A process of participatory design–in which users of the ward environment, staff and patients, influenced the outcome–was initiated on Ward 8 at Cleveland State Hospital, an old Kirkbride-modeled mental hospital where several experimental ward environments were created by ARC (Architecture-Research-Construction), an interdisciplinary team of designers and social scientists who researched, designed, built, evaluated and documented the new ward settings. At the end of that process, interaction–one observable category of ward activity–was more than doubled among a group of 22 long-institutionalized patients over a 16-month period, as observed and measured by “behavioral mapping,” a technique for studying influences of immediate environments on the behavior of groups.
Evaluation and Reduction of Error in Medical Judgments
Authors: Pickett Ronald M.
Published: January 2012

Accuracy and consistency in many aspects of medical judgment have been shown to be disconcertingly low. This report focuses on error in medical judgments involving sensory evaluation of signs, symptoms and laborabory specimens. Four main factors that determine the extent of error in sensory evaluations are described, and five main approaches to error reduction are listed. A desirable general approach to error analysis is outlined and one simple expedient for reducing error is discussed.
Astm Standards for SKI Binding Performance: Environmental Testing of Releasable Ski Bindings
Authors: Shealy Jasper E.
Published: January 2012

This research involves the generation of standards for release bindings used in downhill or “Alpine” skiing. The American Society for Testing and Materials (ASTM) is currently working on voluntary consensus standards for the manufacture of skiing equipment. One aspect under investigation is the effect of specific environments (vibration, contamination and corrosion) on the stability of the functional release characteristics of bindings.

The results of the current research indicate that vibration tests affect bindings that have threaded fasteners without any locking provision. The dust and dirt tests affect bindings that rely on a moving boot-binding interface more than those that don't. The salt-fog exposure affected all metallic surfaces. Cast aluminum surfaces were more affected than forged, rolled or drawn surfaces. Stainless steel was relatively unaffected. Bearing surface deterioration was the major factor. Some interaction with boot-binding interfaces did occur. Limits are suggested that differentiate between high and low quality bindings.
Left Out “Lefties” in Design
Authors: Laveson Jack I. , Meyer Robert P.
Published: January 2012

Many minority groups such as the handicapped, blind and hard-of-hearing pose special consumer design problems. One minority which has received minimal attention in the United States is the 22 million lefthanders. These people have either had to adapt or suffer in silence. Problems peculiar to left-handers need not occur as they are correctable through proper design. There is little human factors data, however, to provide guidance for proper design. A task analysis approach, based on force utilization, overcomes many of these obstacles by considering in detail the way tasks are performed. In a systems approach such as this, the required actions and the ways they can be performed by both the righty and lefty are defined. The right- and left-handed modes can be compared and contrasted and recommendations made for (1) no product modification (2) modification to make the product left- and right-hand compatible, or (3) total redesign. While the approach has been applied only to consumer products, it has the potential for extention to more complex situations.
Anthropometry as a Variable in Human Factors Engineering
Authors: White Robert M.
Published: January 2012

In the efficient human engineering of man/equipment systems, information on the range of variability in human body size and proportions is of basic importance. Such information is to be found in anthropometric data. The anthropometric data to be utilized, however, should be that on the population for which the equipment is intended. Anthropometric data on four representative body dimensions are presented and discussed to illustrate the range of variability to be found in diverse populations.
Shuttle Remote Manipulator System Workstation – Man-Machine Engineering
Authors: Brown Jeri W.
Published: January 2012

A major subsystem aboard the Shuttle Orbiter, the Remote Manipulator System (RMS) provides the capability to deploy and retrieve free-flying satellites, support attached payload operations, and aid in crewmember rescue from a disabled vehicle should the requirement arise. The Remote Manipulator System consists of 15.3-meter (50-foot) articulated booms, end effectors, operator workstation, and closed circuit video, power and control subsystems. The manipulator booms (or arms) and end effectors are located in the Orbiter payload bay and operated from inside the cabin by one crewmember. This paper is primarily concerned with the design and development of the RMS operator's workstation, the man-machine engineering features and interfaces, and man-in-the-loop simulations and testing results obtained to date by the National Aeronautics and Space Administration (NASA).
A Human Factors Comparison of Three Cargo Trucks
Authors: Harris Ward A.
Published: January 2012

As part of a U.S. Army field test, three cargo trucks and three truck-tractors were compared on a number of human factors variables. Among the variables were noise level in the passenger compartment and ride quality at the driver's seat. Ride quality was measured in terms of the energy absorbed by the driver as the vehicle traveled over a specified terrain profile at a specified speed. The vehicles were judgmentally evaluated by a sample of 23 drivers on 35 other human factor variables in the categories of adequacy of driver compartment; visibility; instruments; controls; steering, braking and shifting; and ride. Differences were found among the vehicles on most of the variables.
The Integrated Application of Job Enrichment and Ergonomics
Authors: de Jong John Rendel
Published: January 2012

Job enlargement (including job enrichment) and ergonomics have developed almost independently until now and are mostly not applied jointly. Moreover, quite a number of cases are known in which aiming at job enlargement has not been successful. Reasons appear to have been fairly often:

• a one-sided emphasis on intrinsic or extrinsic factors • the missing of a systematic method for work (re-)design • the absence of participation by the employees concerned and lower management in the process of job enlargement and its implementation. The present author feels that job enlargement should be integrated into work (re-)design and that the approach applied should be marked by: • the jointly taking into account of functional, economical, technological and human factors, including the systematic removing or prevention of discrepancies between the characteristics of the job and the work situation on the one hand and the needs, abilities etc. of the employees on the other; • participation in the various steps of such an approach by the concerned employees.

One of the goals of a project concerning such a methodology (and that is supported by the Netherlands Social-Economic Council) is to develop training methods for those who play a part in work (re-)design in the indicated sense.
Semi-Autonomous Work Groups in Warehousing
Authors: Alioth Andreas , Martin Ernst , Ulich Eberhard
Published: January 2012

Job design in the service sector has received little attention yet. This paper describes the introduction of semi-autonomous work groups in a warehouse and distribution center of a Swiss supermarket chain. As an implementation strategy principles of participative job design were applied. Two cases are reported, and some analysis of the change process is given.
Assessing Operator Task Loading: A Function Analytic Approach
Authors: Helm Wade R.
Published: January 2012

A human factors evaluation of the P-3C aircraft was conducted to determine the workload implications resulting from design modifications at the sensor and tactical operator stations. The primary objectives of the evaluation were: (a) to determine if equipment and software design changes had significantly influenced the workload of the operators and (b) to determine if the design changes resulted in improved system performance. To aid in conducting this analysis a method known as the Function Description Inventory (FDI) was used. This method requires a series of investigations analyzing the selected operational functions of specific P-3C crew members, with an essential part involving the determination of roles, duties, and tasks performed by the crew members. Next, crew members' judgments were compiled on how important these roles, duties, and tasks were for mission success, how frequently they were performed on a typical mission, how difficult were the activities for the typical operator, and finally, how effective were the systems in accomplishing these operational functions. After combining the FDI results with the results of traditional human engineering analysis, it was concluded that there were substantial workload and system effectiveness changes at all three stations.
Indoor Air Pollution as an Environmental Factor
Authors: Satish Joshi
Published: January 2012

An average person spends most of his time indoors and the quality of indoor air affects his performance and well-being. This justifies the study of indoor air pollution for the development of working and living environments which are comfortable and safe.

As a part of a larger program to study traffic-generated air pollution in the vicinity of streets, a simultaneous indoor/outdoor sampling program was carried out at three sites in the city of Zurich, Switzerland. Parameters included CO, NO, NO2 and HCHO. The results show the direct relationship between indoor and outdoor concentrations of CO, NO and NO2. HCHO concentrations were found to be substantially higher indoors than ourdoors thus supporting the hypothesis that HCHO source could be in the buildings themselves. The importance of indoor air is emphasized, and the interplay of indoor and outdoor air pollution is demonstrated.
Evolution of a U.S.-ECE Improved Headlamp Beam
Authors: Mortimer R.G. , Olson P.L.
Published: January 2012

Conventional U.S. and European headlamps were used as a basis for comparison with three experimental mid beams in field tests to evaluate visibility and glare of alternative “meeting” beams. Mean visibility distances of targets to the left of the drivers, at the center line of the two lane road used, were about half of those for the targets at the right side of the lane. Visibility distance of targets at the left of the lane were slightly greater with the ECE low and the mid beam using the ECE low beam than the other beams, but only close to the meeting point. Mean visibility of targets on the right of the lane was up to 24% greater with mid beams than either U.S. or ECE low beams. Discomfort glare was rated the same for all beams for targets on the right; but less for the ECE low beam and the mid beam using the ECE low beam than the mid beams using the U.S. low beam when observing targets on the left. It was concluded that improved meeting beams should use headlamps similar to the ECE low beam for urban driving, augmented by a third lamp such as the U.S. “type III” lamps used in these tests to form the “ECE-US mid beam” for use as a meeting beam on two lane and divided highways.
Dynamic Biomechanical Model for Sagittal Lifting Activities
Authors: Ayoub M. M. , Bassoussi M. M. El
Published: January 2012

Biomechanical analyses have been performed on many activities in the military, in sports, and in industry. Such analyses can provide Kinematic and Kinetic information. With emphasis on occupational safety and health, there has been a renewed interest in the biomechanical investigations of certain stressful tasks in industry such as those involving the handling of material.

This paper presents the development and application of a “Dynamic Biomechanical Model for Sagittal Lifting Activities”. The model accepts operator characteristics data, operator postural data, and task characteristic data. From this, the model simulates the lifting action and calculates the reactive forces and torques at the various joints of the body. The model also provides data on the compressive and shear forces on the spine at L-4, L-5, and S-1.

Results showing the stresses on the musculo-skeletal system will be presented for typical sagittal lifting activities snowing the differences between leg lift and back lift as well as the effects of weight lifted and size of the container on these stresses. Kinematic information will also be presented.

Finally the usefulness and limitation of the models and future research requirements will be presented.
Diversity of Response Patterns in a Simple Repetitive Uniform Task
Authors: O'Brien James P. B.
Published: January 2012

A 3×3×3 factorial design, N=135, is used to evaluate the effects of three conditions of feedback (zero, low extrinsic, and high extrinsic), three conditions of response pattern restriction (no restriction dictated, restriction to three patterns, restriction to one pattern), and three levels of repetitive-figure manipulation diversity determined by scores on Torrance Tests of Creative Thinking, Form A, Activity III: repetitive parallel lines. The experimental task was to turn nine circularly arranged knobs repetitively in a white visual, broadband audio environment over three 6-minute periods separated by rest pauses.

O'Brien (1976) found significant differences for measures of response variability including pattern changing activity, pattern shifting, error factors, and other measures. An extended ad hoc analysis of that exploratory study is accomplished in which a comparison of percent common patterns emitted evidences that Ss who score differently on the pretest perform with different degrees of uniqueness when they are restricted to repetition of previous patterns, but not when they are free to vary types of patterns emitted. Also, comparison of initial trials indicates that high pretest scorers are more likely to begin the task with rarer patterns, low scorers use more common patterns, and intermediate scorers fall in between.
Finger Motion Analysis in Typing of Texts of Varying Complexity
Authors: Olsen Richard A. , Murray Riley A.
Published: January 2012

Operation of keyboard entry devices entails manual and intellectual skill components. The source material and its effect on short-term memory determines whether the information processing will introduce delays in addition to those from the manual component. The finger timing and motion patterns were investigated for six classes of text material from normal English to numerals and mixed alphanumeric text. Successive keystrokes by skilled typists tend to overlap when normal English text is being entered, while more complex text results in delays between strokes. Finger motion rates also vary, with typists excelling on text and key-punch operators on numerics.
L'Ergonomie Dans L'Ingenierie D'Une Usine a L'Exportation
Authors: Wisner Alain
Published: January 2012

Il existe un marché croissant d'usines vendues „clefs en main” ou „produit en main”. De quelles connaissances doit disposer l'ingénieur pour choisir la technologie, concevoir l'usine, construire ou acheter les machines, préparer les programmes de formation de telle sorte que les relations de la population des travailleurs du pays acheteur avec le dispositif technique importé soient satisfaisantes? Quelles sont les conséquences de la mise en oeuvre de ces connaissances sur les investissements, la productivité et la santé des travailleurs? Quelques cas typiques sont décrits.
Accessibility and Wear of Personal Flotation Devices in Recreational Boating
Authors: Doll Theodore J.
Published: January 2012

Previous research on personal flotation devices (PFD's) indicates that they are highly effective and reliable, but are typically not worn, nor even accessible to victims of boating accidents. It has been estimated that 90% of the drowning victims could have been saved by the use of PFD's. A large-scale study assessed PFD wear and accessibility by direct observation at seven locations across the Continental United States. The percentage of people wearing PFD's, the number of accessible PFD's aboard, the percentage of accessible PFD's worn, and the distribution of various types of accessible PFD's were tabulated. Differences in these measures as a function of location, boating activity, age and sex of the boater, boat length and type, and type of PFD are reported. For example, the wearability of a PFD (percentage of accessible PFD's worn) depended on geographic location, air temperature and activity. The most wearable device for fishing was not the most wearable for waterskiing or other activities. The results are used to generate recommendations for educational and regulatory programs aimed at improving the life-saving capability of PFD's.
Experimental Investigations of Computer Program Debugging and Modification
Authors: Shneiderman Ben , McKay Don
Published: January 2012

Although greater emphasis is placed on the task of computer program composition, debugging and modification often consume more time and expense in production environments. Debugging is the task of locating syntactic and semantic errors in programs and correcting these errors. Modification is the change of a working program to perform alternate tasks.

The factors and techniques which facilitate debugging and modification are poorly understood, but are subject to experimental investigation. Controlled experiments can be performed by presenting two groups of subjects with two forms of a program or different programming aids and requiring the same task. For example, in one study we presented an 81 line FORTRAN program containing three bugs to distinct groups of subjects. One of the groups received a detailed flowchart, but our results indicated that this aid did not facilitate the debugging procedure. Similar negative results were obtained for a modification task.

In other experiments, comments and meaningful variable names were useful in debugging and modularity facilitated modification. Other potentially influential factors, which are subject to experimental study, include indentation rules, type of control structures, data structure complexity and program design.

These and other human factor experiments in programming have led to a cognitive model of programmer behavior which distinguishes between the hierarchically structured, meaningfully acquired semantic knowledge and the rotely memorized syntactic knowledge. Errors can be classed into syntactic mistakes which are relatively easy to locate and correct and two forms of semantic mistakes. Semantic errors occur while constructing an internal semantic structure to a representation in the syntax of a programming language. Modification is interpreted as the acquisition of an internal semantic structure by studying a program, followed by modification of this structure and revision of the code.
The Development of an Accurate Internal Model for High Order Systems
Authors: Eberts Ray E.
Published: January 2012

In order to effectively control or monitor a complex system, the operator must construct an internal model of the system dynamics. An operator's internal model is defined as the internal or conceptual representation of how the operator thinks the system should or will work. The purpose of the research reported in this presentation is to: 1) determine methods to identify the form of the operator's internal model; 2) develop guidelines for system display design and training so that costly errors can be avoided; and 3) determine system display design and the type of training needed so that an accurate internal model is developed. To experimentally study the development of an operator's internal model, a dynamic high order control system was modeled and displayed to subjects over a CRT screen. Subjects were required to control the system through inputs on a joystick. The dynamics of this high order system were described through a set of differential equations. Without some kind of assistance, the solution to a set of differential equations is difficult to conceptualize, and, consequently, it is difficult for an operator to form an accurate internal model of the system dynamics. To help the operator internalize the system dynamics, upon control input the solutions to the differential equations were presented spatially on the CRT through computer augmentation. In the experiments reported, subjects were trained under two conditions: 1) with computer augmentation (the spatial representation of the solution); and 2) without computer augmentation. After training (about five hours per subject) performance was measured in terms of performance accuracy and mental workload needed to perform the task. The differences between the two groups in their ability to internalize the differential equation solutions was examined by providing the operator with a desired state of the system at a specified time and then testing the operator to see if he could choose the correct solution. Results indicated that with the right kind of training and the correct computer-controlled display augmentation, operators could accurately internalize the complex relationships needed to control this high order system.
Computer-Augmented Retrieval of Help Information for Novice Users
Authors: Cohill Andrew M. , Williges Robert C.
Published: January 2012

Appropriate design of HELP is important particularly for novice users of software systems. Three methods of controlling HELP displays were evaluated in a text editing task. The three methods were the initiation of HELP (i.e., user vs. computer), The selection of a particular HELP sequence (i.e., user vs. computer), and the type of format (i.e., on-line vs. hard copy). These three variables were crossed in a between-subjects design along with a control condition of no HELP available to produce a total of nine separate test conditions. The various HELP configurations improved time to edit and reduced the quantity of errors and editing commands when compared to the no HELP control condition. Additionally, the efficacy of the various HELP configurations differed among themselves. It was concluded that for novice users, the optimum HELP system configuration was one in which the user controls the initiation and selection of HELP displays, and the information is stored in a hard-copy manual. The implications of this conclusion are discussed in terms of the design of HELP to facilitate browsing and comparison features.
Some Performance Correlates of Technical Illustration Level
Authors: Hoecker Douglas G.
Published: January 2012

This paper reports preliminary results from a pilot experiment to assess how levels of illustration affect the performance of persons who require technical documentation in order to solve a problem. Fifteen inexperienced undergraduates used an oscilloscope and a volt-ohmmeter to check out and troubleshoot the printed circuit board of an electronically— triggered oscilloscope camera. Each subject solved three similar problems, guided by a “core path” of textual procedures that remained constant while the level of illustration was changed from one problem to the next. Time and error data both showed a large effect (roughly a factor of 2 times “experienced” levels) for the interaction of illustration level and experience on the problem. While these illustration levels had little effect on how much time subjects spent visually consulting the illustrations themselves, there were effects on time spent doing other components of the task.
The Effects of Warning Message Highlighting on Novel Assembly Task Performance
Authors: Zlotnik Morris A.
Published: January 2012

A review of examples and specifications relating to critical operating procedures revealed considerable variation in recommended standards for highlighting warning messages. An experiment was therefore conducted to examine the effectiveness of various methods of highlighting warning messages contained in the instructions for a novel assembly task. Findings indicated that the presence of warning messages shortened task completion times and reduced error rates between the experimental and control groups.
Thermal Comfort as Affected by Chair Style and Covering
Authors: Rohles Frederick H. , Krohn Rachel J.
Published: January 2012

A total of 192 subjects divided into 8 groups of 12 men and 12 women evaluated 8 chairs that represented 4 different models (executive, manager, conference and side chair) each with two types of covering, cloth and vinyl. The exposure period was for 2 hours at 78F/50%rh; the subjects all wore identical clothing under near sedentary conditions. The results showed that neither the covering of the chair nor the chair model affected the thermal sensations (feelings of hot, warm, cool, etc.); however, thermal comfort was greater in cloth covered chairs than in vinyl covered chairs. Three scales were developed which measured chair comfort, chair size and chair style. The Executive, Manager and Conference Chairs were equally comfortable, but significantly more comfortable than the Side chair; the Executive chair was judged larger than the other three chairs and women judged the chairs to be larger than men; and the Executive, Manager and Conference chairs were judged more stylish than the Side chair. The findings are discussed in light of the methodology and the Steelcase/Harris Office survey.
Evaluating a Multi-User VDT Workstation in a Working Environment
Authors: Wallersteiner Ulrika
Published: January 2012

With the advent of job rotation and the sharing of VDTs by a multiplicity of users, it is becoming necessary to invest in a workstation that is multi-user orientated. Considering the numerous systems on the market, a dilemma arises as to system choice. Buying furniture that is adjustable does not reflect which user is accomodated by the adjustments.

Four chairs and four desks were evaluated against the ergonomic ‘ideal’ standard. This provided an objective measure in the form of an ergonomic composite score. The lower the score, the closer it approaches the ‘ideal’. Subjective evaluation was gathered through a questionnaire. Interestingly the results of the ergonomic composite scores reflected users subjective preferences. Using both these methods of evaluation it is possible to make a choice and invest in the best system available The primary deciding factors are the ‘ease’ of adjustment and the ‘range’ of adjustments possible.
Doing the Same Work with a CRT Terminal and with Hardcopy
Authors: Gould John D. , Grischkowsky Nancy
Published: January 2012

There is considerable concern about the uses of computer display terminals in people's work. Some of this concern centers on reported feelings of fatigue - visual and other ways. This laboratory experiment attempts to understand how much, if any, a CRT terminal contributes to these feelings and how much the work itself does. Twenty-four participants proof-read material shown on a CRT display and, on another day, proof-read similar material printed on hardcopy. Their performance, feelings, and vision were measured each hour. Results are still being tabulated.
Human Factors Evaluations of Logic in Kodak Disc Cameras
Authors: Lucas Richard L. , Heckaman Rodney L. , Faulkner Terrence W.
Published: January 2012

Kodak disc cameras were designed to be as “decision-free” as a camera could be in today's technology. Many features have been included to implement this goal. An “always ready” flash system is among the features and employs no less than three methods of charging to be sure that it will have sufficient energy for flash at all times. The adequacy of these features was assessed in an earlier study by building results of a simulated use test into a mathematical model of flash performance. The “wake-up switch,” a fail-safe charging mechanism, was included in this earlier study and was helpful in providing flash charges but left some concerns regarding accidental actuation in certain circumstances. The current study describes a carrying test in which the designs of four different switch configurations were assessed. Recommendations were made for production switches to maximize performance and consumer satisfaction.
Methodology for Exploring Voice-Interactive Avionics Tasks: Optimizing Interactive Dialogues
Authors: Mountford S. Joy , North R. A. , Metz S. V. , Warner N.
Published: January 2012

Two experiments were performed to investigate the most advantageous format for interactive dialogue between pilots of a fighter aircraft and an on-board voice recognition and synthesis system. A representative task was chosen among those anticipated to be performed using a multi-function display and control system during high workload mission segments. The first experiment compared different methods of progressing through a “menu driven” sequence using voice I/O. A second experiment was conducted using the dialogue approach that proved easiest to use in the first experiment, and compared performance of voice I/O vs. keyboard-display I/O in timeshared conditions with a simultaneously performed flight control task. Results showed that after an initial training period with voice I/O pilots performed the flight control task with little or no disruption from the voice interactive data entry task, but showed significantly higher degradation when required to use the keyboard system.
Methodologies for Evaluating Training Products and Processes
Authors: Carter Richard J.
Published: January 2012

Methodologies for conducting training effectiveness evaluations (TEE) of ongoing Army training were detailed. The design process, consisting of a literature search and formative evaluations, was discussed. The developed TEE system was described.
A Health Evaluation Study of Kraft Pulp Mill Workers
Authors: Banister Eric W. , Fadl Samia , Brown Stephen , Sprince Nancy , Oliver Christine , Smith Tom , Diewert Gordon , Berry Joffre
Published: January 2012

A health evaluation study of Kraft Pulp Mill Workers in Prince Rupert measured the responses of a large sample of Mill workers (n=326) based on a health questionnaire, a medical examination, pulmonary function tests, rest-ing EKG and blood chemistry analysis. A smaller sub group (n=84) were tested on their response to exercise.

On site measurement was made of contaminant gases in several mill areas shortly after the physiological and medical tests. Based upon the chemical analyses carried out, an Environmental Hazard Index was developed to quantify the degree of workers to mixed contaminants of various work sites. After the confounding influence of age, smoking, alcohol intake, family history of coronary artery disease and activity pattern were account -ed for, the residuals of the physiological and clinical dependent variables was related to the mean Environmental Hazard Index of groups of workers in different work sites. By this type of analysis, intriguing relationships become apparent between deficiences in physiological function and the size of the Environmental Hazard Index.

This paper illustrates the relative ease with which deficiencies in any work place may be detected. This contrasts markedly to the ease with which practical solutions to remedy deficiences may be developed if any company is to retain its viability. Nevertheless a solution to the hazard considered in this paper may be the development of an individual Worker Health Hazard Registry which tags each worker's daily exposure and accumulates it to identify a danger point at which physiological deficiences occur. The worker would then be found other work at a contamination free site until his personal hazard index had declined to a low level.
The Perception of Flicker and Glare on Computer CRT Displays
Authors: Isensee Scott
Published: January 2012

Twenty-one subjects rated their discomfort due to direct glare, reflected glare, and flicker while viewing a CRT display under various conditions of ambient illuminance, video luminance, and video polarity. The angle away from the CRT at which the subjects first noticed flicker was also measured. Levels of these design and environmental variables which minimize discomfort are suggested. Video luminance was shown to have the greatest impact on comfort. Methods of reducing glare and flicker are discussed.
Critique of Methods Employed in Human Factors Research on VDTs
Authors: Schurick Jayne M. , Helander Martin G. , Billingsley Patricia A.
Published: January 2012

This report summarizes a review of human factors research on VDTs. The main areas of interest included workstation design, character and display design, work organization, lighting and reflectance, and visual discomfort. Experimental studies were critically reviewed for the soundness of their methodologies and conclusions. In many of the studies, there were problems of interpreting the results due to careless oversights on the part of the researcher(s), for example, the inappropriate selection of subjects or lack of a control group. Due to different subject selection strategies and different VDT parameters, the integration and generalization of research results is difficult.
The Power Law of Motor Control: Some Diverse Applications
Authors: Kvålseth Tarald O.
Published: January 2012

The generality of the recently proposed power law of motor control is further demonstrated in this paper by using it in two widely different areas of human motor activity. First, it is used to provide simple mathematical models of motion time for four different predetermined motion-time systems (PMTS): MTM-1, MTM-2, Work-Factor and BMT. Second, it is used for human locomotion by modelling the relationships between time, speed and distance for various athletic events based on world-record data. Some implications of the results are mentioned. In all cases, the power law is found to provide excellent fits to the empirical data.
Averaged Cross-Correlations with Differentially-Stable Variables: Fewer Subjects Required with Repeated Measures
Authors: Bittner Alvah C. , Dunlap William P. , Jones Marshall B.
Published: January 2012

Averaging cross-corrleations between repetitions of two variables was evaluated as a method for over-coming limited (small) subject sample sizes. Analysis revealed greatest utility when reliabilities were low and numbers of replications were large. Simulation revealed less biased and variable estimates based upon averaging correlations than upon corresponding correlaions of averages (sums). Averaging correlations is recommended when subject samples are limited.
An Anthropometrically Adjustable Seat for Low Seam Mining Applications
Authors: Hartley Craig S. , Cooksey Ray W. , Kwitowski August J.
Published: January 2012

Low seam underground coal mines require use of heavy machinery having interior cab heights that may be lower than 33 inches. Current mining machines typically provide operators with non-adjustable seats consisting of heavy metal slabs or, in many cases, provide no seat at all. However, the limited workspace height forces the operator to control his machine from a reclined or supine position that requires special support. The problem may be exacerbated by the presence of a canopy that may further reduce the workspace height by several inches or more. While some Air Force research has examined low-profile seating anthropometry, the special ruggedness and low-level technology of the mining environment imposes unique design requirements not addressed by the Air Force research. This paper describes the development of a special anthropometrically adjustable seat that can provide comfortable body and head support in mining machines having very low workspace heights. Anthropometric analyses using published data and 1/4 inch scale drawing board manikins were used to establish design parameters for a medium fidelity adjustable seat mockup. Formal evaluation of the mockup confirmed, and in some cases altered, seat design parameters. The final seat design integrates refinements from the evaluation results and solutions to the adjustment problems.
Average Operator Inaction Characteristics with Lever Controls — Study of the Column Mounted Gear Selector Lever
Authors: McCarthy Roger L. , Finnegan James P. , Fowler Graeme F. , Brown Stuart B.
Published: January 2012

Sixty drivers executed 1800 automotive transmission shifts from DRIVE to PARK. These shifts were performed in a total of six vehicles. Among analoq data recorded during each shift are longitudinal (pull) and rotational forces and rotational position of the lever. Analysis reveals that drivers typically impact the mechanical stop associated with PARK position with approximately one and one-half times the minimum force required to complete the shift. Shifts to PARK are completed in an average of 0.58 seconds, and an additional 0.83 seconds is spent continuing to apply force to the lever after PARK position is achieved. Most (80%) shifts are executed without regard for intervening detents. Those drivers who show hesitation in movement typically hesitate for 50 milliseconds. Whether a driver shifts continuously or with shortduration hesitation appears to be driver style or insert plate impact, independent of vehicle.
Perception of the Moment of Inertia of Hand Tools
Authors: Zahner Carol , Kaminaka M. Stephen
Published: January 2012

Suppose I ask you to select one from five identically manufactured baseball bats. Apart from surface texture and color, the dimensions and mass of the bats are exactly the same. However, as you test out the bats with a few swings you would very likely arrive at a definite preference for one or the other of the five. The mass distribution within the wood of the bat changes its feel. In mathematical terms, this difference in feel is best described by the moment of inertia.

This presentation demonstrates the relationship between the measured moment of inertia of a hand implement and the users perception of the stimulus. Simple mock tools, all with the same weight and size but varying moments of inertia were rated against a standard according to the amount of moment of inertia. A functional relationship between the perception and the magnitude of the stimulus has been established.

Observers of this presentation will be able to familiarize themselves with sensations and numerical values of moment of inertia of various hand tools and experimental test pieces. The measurement of moment of inertia is complicated by the geometry of the tool, the weight distribution, and the point of hand grasp. The values are unfamiliar. The concept of what causes the sensation is not simple and, as others have pointed out, our vocabularies are usually inadequate to describe what causes the change in sensation that is felt with a change in moment of inertia.
Membrane Keyboards and Human Performance
Authors: Cohen Karen M.
Published: January 2012

Membrane switch technology has become increasingly popular in many consumer-oriented products due to its low production cost and design flexibility. However, the absence of familiar key travel associated with membrane switches removes an important, direct source of feedback to the user with respect to specific keystrokes. Hence, the conventional wisdom has been that membrane switches without key travel are unacceptable for keyboard applications such as typing tasks.

This paper describes systematic human factors research in which typing performance using a commercially available membrane keyboard and a conventional, full-travel keyboard was compared for subjects representing different levels of typing proficiency. Each subject (N = 21) used a membrane keyboard for 3 consecutive (or nearly consecutive) days and a conventional keyboard for 3 consecutive (or nearly consecutive) days. Each day of experience consisted of a one-hour session in which various typing exercises were completed. Traditional tests of typing performance were administered at the beginning and end of each session.

The results indicate that for non-touch typists there was little difference in performance between keyboards. For touch typists performance with the conventional keyboard was initially much better than that with the membrane keyboard. There was, however, rapid learning with the membrane keyboard such that, within a few sessions, the difference in typing performance between the conventional and membrane keyboards was reduced substantially. There remained some advantage for the conventional keyboard, compared with the membrane keyboard evaluated here. Future work will be aimed at measurement of the additional improvement in performance resulting from extended practice with better-designed membrane keyboards.
A Work Clothing Design Suitable for the Needs of Low Coal Miners
Authors: Selan Joseph L. , Caddel Doris K. , Ayoub M. M. , Smith James L. , Peay Jim
Published: January 2012

Due to problems associated with the present design of coveralls used by miners in low coal, coveralls were designed which incorporated comfort and safety features which would alleviate these problems. The experimental coveralls proved superior to standard coveralls in terms of comfort, safety and worker productivity.
Physiological Effect of Partial Spectrum Lighting on the Human
Authors: Zabcik Don A. , Hottman Stephen B.
Published: January 2012

Light could be the most important environmental input, after food, in controlling bodily functions. The extent of this control on humans has become a recent topic of investigation. Investigation of the effects of various frequencies of illumination is a topic relatively unexplored through endocrinology or by examining physiological effects in humans. This research investigates the effect of partial spectrum lighting on the psychomotor performance of nine subjects. The physiological effects as represented through psychomotor performance was determined by measurements taken on grip strength, dexterity, and reaction time. From the results there was no basis on which to reject the null hypothesis. Therefore, no significant psychomotor differences were found between the three light sources tested.
Relationship of Work Pace to Worker Physiological Cost in a Human-Machine Production Task
Authors: Das Biman
Published: January 2012

The increased work pace of the operators in a human-machine production task resulting from the provision of an assigned hard-task production standard in conjunction with production quantity and quality feedback, did not have a significant adverse effect on worker physiological cost. The operators who were provided with this experimental condition had an average first recovery heart/pulse rate of 81 beats per minute (bpm), which was within the normal range of 60 and 100 bpm for light work load and certainly within the safe limit of 110 bpm. Some of the operators pulse rate did not change, while for some other operators it even went down after the task performance. The pulse rate of some of the operators showed no recovery while some other operators pulse rate showed reverse or negative recovery.
Redundancy in Coding of a Visual Display as Assessed by a Signal Detection Paradigm
Authors: Najjar Lawrence J. , Patterson Michael J. , Corso Gregory M.
Published: January 2012

A signal detection paradigm was applied to performance of a visual search task under varying degrees of shape-color redundant coding and two levels of practice. The coding conditions were (1) Black and White, (2) Totally Nonredundant, (3) Partially Redundant, and (4) Totally Redundant. In addition to the traditional signal detection measures, subjective coding condition preference ratings were also recorded. Generally, the objective performance measures were influenced by practice. However, neither the objective nor the subjective measures were affected by coding conditions. A significant Coding Condition by Practice interaction on the percentage of correct responses was also found.
Human Reliability and Fault Tree Analysis
Authors: Stewart Catherine
Published: January 2012

A method was developed to collect data on Human Reliability as an adjunct to Fault Tree Analysis. The need for these data, the method used for data collection, and the utility of quantified data for Design Support are described. Recommendations are made for research to raise the sample size and validate the estimates.
HFS Job Description Survey: Where We Work, What We Do
Authors: Sanders Mark S.
Published: January 2012

This paper reports findings from a survey of members, fellows, and associates of the Human Factors Society living in the continental US. Data are presented on gender, ethnic background, salary, types of organizations in which we work, workgroup size and composition, and activities performed on the job. Analyses are presented by highest degree held and by type of organization.
Where and What are the Data in Human Factors?
Authors: Meister David
Published: January 2012

The major points of this paper are: (1) Human Factors (HF) data have no value unless used; (2) the major use of HF data should be quantitative prediction of human performance; (3) predictive methods exist but the data banks to support them do not; (4) HF research should be directed by data bank needs, rather than by researcher idiosyncracy.
New Technology for Training: An Evaluation of the Air Controller Exerciser (ACE)
Authors: McCauley Michael E. , Root Robert W. , Muckler Frederick A.
Published: January 2012

This paper describes the evaluation of an experimental prototype training system called the Air Controller Exerciser (ACE). The system was developed to demonstrate the use of new technologies for training including computer speech recognition and generation, videodisc, automated instruction, automated performance measurement, syllabus control, and speech-interactive simulation. Empirical studies were conducted to determine the accuracy of the speech recognition system, validate the performance measurement system, and compare ACE with the traditional training program with a transfer of training test. ACE reasonably showed the potential for the use of new technologies in training. However, a number of changes and improvements would be necessary before ACE would be acceptable as an operational training system.
Symposium on Human Factors Standards and Guidelines
Authors: Helander Martin G.
Published: January 2012

The Human Factors Society has decided to become increasingly involved in standards writing activities. This panel will give an overview of some of the most important human factors standards.