bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Tolerance of Subjective Discomfort Induced by Pressure Applied to the Forearm
Authors: Stobbe Terrence J. 
Published: January 2012

A study was conducted to determine the ability of the forearm to support weight. The criteria used was the psychophysical effect of pressure on the human forearm. The study was conducted in conjunction with research on a forearm supported tool. Three levels of pressure were applied at different times to two distinct locations on the forearm. Effect was measured in terms of the elapsed time until the subject reported experiencing a subjectively defined level of discomfort. Both sexes were used as subjects in the study. The results indicate that males tolerate pressure induced discomfort longer than females, pressure applied close to the elbow is tolerated longer than pressure applied closer to the wrist, and tolerance decreases rapidly as pressure increases. Based upon the results, recommendations are made for both future tool design and additional research.
Design and Evaluation of a Personal Dry-Ice Cooling Jacket
Authors: Duncan Jerry , Konz Stephan 
Published: January 2012

A personal dry-ice cooling jacket for workers in industrial heat stress environments was developed following three stages of prototype design and evaluation. Model-B2 was evaluated in two laboratory heat stress environments (dry-bulb temperatures of 35 and 45 °C) on two male subjects pedalling 60 minutes. Garment variables were dry-ice surface area and pocket insulation. Mean heart rate throughout the 60 minute exposure was 14 beats/min less with the jacket in the 45 °C environment and 18 beats/min less in the 35 °C environment. Mean rate of sweat loss was 0.06 kg/hr·m2 less with the jacket at 45 °C and 0.21 less at 35 °C. Mean rectal temperature was 0.61 °C less with the jacket at 45 °C and 0.49 °C less at 35 °C. Both the head and arm temperatures were significantly cooler while wearing the jacket. Oxygen uptake was 24% higher with the jacket, suggesting that heat production by non-shivering thermogenesis may occur when the jacket is worn. Dry-ice surface area affected skin and rectal temperatures.
A Systems Approach Comes to Personnel Management
Authors: Leuba Harald R. 
Published: January 2012

A perennial problem — performance evaluation — yields to a dependable problem solving approach. As the result of a systems analysis approach, we were able to: (a) Identify the purpose of performance evaluation: (b) Specify the value of performance evaluation: (c) List a set of specific characteristics which must be true of a performance evaluation system if it is to work well; and (d) Design an illustrative performance evaluation system which meets those criteria, and which works! The illustrative performance evaluation system is now available for use.
The Effectiveness of Pre-Employment Strength Testing for Manual Materials Handling Jobs
Authors: Chaffin Don B. , Herrin Gary D. 
Published: January 2012

With the advent of both affirmative action programs for women and disabled individuals and the growing need for better occupational health and safety programs in heavy industry, it has become necessary to develop more objective pre-employment selection and employee placement tests. This paper reviews the eight years of research conducted on this subject by the University of Michigan, Human Performance and Safety Research Laboratory. Various human strength testing methodologies are described and critiqued. Population strength data are reviewed as they pertain to the problem of matching a person's physical capabilities to a job's physical demands. The development and use of biomechanical strength models are reviewed, and their potential contributions and limitations are enumerated. Several major results of the use of such models for the design of manual materials handling tasks are presented. The transition from such biomechanical analyses to the development of a physical job evaluation methodology is presented. Two studies using this job evaluation methodology are then described. The first study involved over 100 jobs requiring significant manual materials handling which were located in five different plants. The workers on these jobs were strength tested. Any low-back problems developed by these people were carefully documented over a one-year period. The results indicated that those jobs requiring high strength performance were associated with about an eight times higher incidence rate of low-back pain than the jobs having little strength requirement. Also, it was shown that those employees having a high strength capacity were significantly less prone (about 3X less) to low-back pain when required to lift heavy loads than their weaker peers. The second study describes a larger on-going study of the same nature as the first. This study involves over 900 job evaluations. The jobs are located in six different plants. As people are transferred or hired into these jobs, their strengths are assessed by standardized tests, and a medical history is obtained. Both supervisor performance ratings and medical incident data are recorded while the person remains on the job. Correlations between the job demands relative to a person's strength test results and their performance and medical incident scores are reported as a measure of how effective strength testing could be in achieving a better employee/job match.
The Neglected Alliance: Human Factors and Market Research
Authors: Cannon Thomas G. , Hasty Ronald W. 
Published: January 2012

The traditional role of human factors has been to support engineering activity in relating man to machines. This relationship has been uncritically accepted as appropriate in the consumer product area with the result that most human factors activity takes place during engineering development. The human factors specialist in such circumstances often finds that proper weight is not given to human factor requirements when they conflict with engineering goals. Many of these conflict problems faced by human factors specialists in achieving acceptance by manufacturers of consumer products could be resolved by demonstrating that human factors research can complement and expand the role of marketing research as it relates to new product development. Marketing research has developed as a specialized communications function to obtain and analyze information about the market and the companies' product, promotion, distribution, and pricing activities in serving it. The role of marketing research relative to product planning varies by company, many, if not most, major firms use marketing research to define the market in terms of types, numbers, and kinds of customers, customer needs regarding a product category, what products are satisfying those needs, the important product attributes, and the standards used by consumers to evaluate the efficiency of the product. This paper focuses on the areas where the role of marketing research in new product development has been ill defined. A complementary role for human factors methodology in defining new product opportunities and specific product attributes is postulated. Suggestion's are made for promoting greater awareness among marketing specialists of the benefits offered by the use of human factors research.
A Computer Simulation Approach for Analyzing Occupational Accidents
Authors: Smillie Robert J. , Ayoub Mahmoud A. 
Published: January 2012

How do accidents happen? A question that plagued scientific research for years, but remains the main concern for research and practitioners in safety and health. No one theory seems to be adequate to explain all accidents. Epidemiology offers some insight into the accident investigation by analyzing the interaction of host, agent, and environment. Only the modeling approach offers the flexibility needed to study all the factors involved in the accident phenomenon. This study used a computer algorithm, the Graphical Evaluation and Review Technique (Q-GERT), to model the accident process. Five simulation examples were presented to illustrate the basic concepts and flexibility of the proposed approach. Discussion focused on the usefulness of this simulation technique as an aid for the accident investigator in the discovery of potential hazards in the occupational system.
Typical Features of Tasks in Which Accidents Occur
Authors: Saari Jorma 
Published: January 2012

The aim of the study was to determine the typical features of tasks in which accidents occur. The study was based on the hypothesis that work hazards do not themselves cause accidents but that certain task characteristics have a significant effect upon the probability of accidents. Tasks in the metal industry were observed for 3 months. Both the task and the working conditions involved were described for every accident that occurred in certain factories. The tasks performed in randomly selected workplaces of the same factories were also described.
The Development of Sammie for Computer Aided Work Place and Work Task Design
Authors: Bonney M.C. , Case K. 
Published: January 2012

Computer assistance with the design and evaluation of work places and work tasks is relatively new. However, a variety of approaches and models have been used by different workers and the work has moved beyond testing feasibility towards providing designers with a practical tool. This paper traces the development of SAMMIE and associated software and examines the lessons that this holds for future developments. The original development which started in 1967 consisted of a man model, a work place modelling system and a way to describe and evaluate work tasks. The restructured SAMMIE system places greater emphasis on usability and the structuring of the software. The decisions involved in the modelling, the facilities included in the model and the implications for data collection, presentation and accessibility are examined in the light of case studies performed and proposed design uses.
Schema Pointer plus Tag Model and Interior Design
Authors: Cohen Andrew D. 
Published: January 2012

The present study was a test of two theoretical models which attempt to explain memory for interior designs. One model proposed by Brewer and Treyens predicted better memory performance for typical items while a Schema Pointer Plus Tag model predicted better memory performance for atypical. Ten scenarios or verbal descriptions of specific rooms and commercial establishments were presented to 40 subjects. These scenarios contained items generated and then rated on typicality to the scenario by two previous groups of subjects. Recognition ratings were then performed by the group which was presented with the scenarios immediately after presentation. Hit and false alarm rates were computed along with d' scores as a measure memory retention. ANOVAs were computed with typicality of the items as the independent variable with hit rates, false alarm rates and d' scores as the dependent measures for each. The data confirmed the Schema Pointer Plus Tag model proposed by Graesser (1981). Further research and implications for interior design are discussed.
Talking Keyboard for User Guidance in Multifunction Systems
Authors: Geiser Georg , Schumacher Wilfried , Berger Lothar 
Published: January 2012

For the important task of function selection when using technical systems, e.g. measurement and programming devices or consumer products, a talking keyboard is proposed which offers user guidance adapted to man's skills. This keyboard is equipped with a voice output module and special keys fitted with two sequentially activated switching contacts. By means of the first contact the user is enabled to select vocal user guidance information whereas by the second contact the selection of a particular function is achieved. By closing the first contact repeatedly, spoken hints with more and more details are available. The user can, however, suppress or interrupt these instructions by switching over to the second contact. In this way the talking keyboard may be used adaptively by untrained and trained users as well. Furthermore, it is suited for blind operation under severe visual load conditions, or in the dark, and it serves to the visually handicapped. For a prototype of the talking keyboard, a moderately priced voice output module with a vocabulary of 150 words was selected. For test purposes, selection is effected via a process computer. For practical use, selection is realized by a microprocessor. Pilot experiments with untrained users of a simulated machine tool show, that the time spent in consulting the operating manual during the task is clearly reduced.
Application of a Hybrid OVD/CIG System to Tactical Map Problems
Authors: Barker Richard A. , Wilson Susan 
Published: January 2012

Today's combat commander is faced with a two-sided problem. First, since the modern battlefield is characterized by mobility, lethality and speed, the commander and his staff must digest more tactical information and make decisions faster than ever before. Second, the current manpower problems may mean that less qualified personnel will have to operate today's highly sophisticated C3I equipment. Therefore, future tactical systems must be designed to (1) aid the combat commander by presenting precise and timely information in the most user-efficient manner possible and (2) require a minimum of training in their operation. In general, tactical maps show a requirement for two distinct types of information. The first type is background images, such as terrain, that are generally fixed but highly detailed. The second type is information that changes rapidly, such as order of battle or an interactive “scratchpad” overlay. The Boeing sponsored program uses computer image generating (CIG) techniques to display both types of information. The background images are generated off-line and stored on an optical video disc (OVD) for random retrieval when required. Rapidly changing data are generated in real time and electronically overlayed on the background information. CIG techniques allow display of only the information germane to the problem at hand so that screen clutter is reduced. It also allows the generation of special effects such as zoom magnification, low altitude horizontal points of view, and specially coded features. An example of a specially coded feature is a background display in which the terrain slopes that are too steep for armour to climb are color coded. These special effects will allow unique user interactions, one of which is simulating a low level reconnaissance “flight” by shifting the low altitude horizontal field of view to consecutive viewpoints. Control of the display is done in a user oriented manner using a touch sensitive screen on the CRT and a special purpose keyboard. Computer synthesized speech provides optional prompting and supplementary instructions. Menu selections on the CRT and special purpose keyboard are designed to lead the user along the available paths to the desired information.
Lift Angle and its Effect on Stresses to the Low-Back
Authors: Garg Arun 
Published: January 2012

A laboratory study was conducted to study the angle of lift from the trajectory of lifting motion. Six male college students were required to lift three different load levels (40, 70, and 100% of maximum acceptable weight) from the floor to a height of 81 m. Four different box sizes (25, 38, 51 and 63.5 cm) and two different body postures (squat and free style) were employed. Maximum acceptable weights were determined using a psychophysical method. Motion trajectory was investigated by using stroboscopic photography. A biomechanical model was used to study the effects of lift angle on forces and moments imparted to various body joints. Analysis showed that lifting motions are not performed vertically up but rather at an angle to the vertical. The lift angle increased with an increase in the weight of the load (p < 0.01). Biomechanical evaluation showed that the lifting of a load at an angle from the vertical resulted in decreases in both the compressive force at the L5/S1 disc and moments at various body joints (except knee and ankle). The net effect of lifting at an angle was an increase in the percentage of the population capable of lifting a given load. Effects of lift angle on biomechanical stresses to the body and the differences between the psychophysically determined maximum weights and the NIOSH recommended “maximum permissible limits” are discussed.
Development of a Human Atlas of Strengths
Authors: Hafez H. A. , Cidcumb C. F. , Reeder M. J. , Beshir M. Y. , Ayoub M. M. 
Published: January 2012

In spite of the technical progress achieved during this century, muscular energy of man is still required to perform many tasks. In order to assess these tasks, operator strength must be considered. This paper describes the procedures used to establish an Atlas of Strengths for this purpose. One sample was drawn from each of the male and female populations. Each sample consisted of 25 college students whose static and dynamic maximal strengths at five body joints were assessed. Measurements were taken using the Cybex II Isokinetic apparatus at three different speeds: 0 rpm (static), 5 rpm, and 25 rpm. At each speed, torque exertions began at different starting positions and covered a specified range of motion for dynamic measurements. Sagittal plane measurements were taken and measurements in other planes of motion at angles away from the sagittal plane were taken for some of the joints. The main results of this study are discussed.
Critical Human Factors Issues in Nuclear Power Generation and a Recommended Comprehensive Long Range Plan
Authors: Hopkins Charles O. , Snyder Harry L. 
Published: January 2012

A comprehensive long range human factors plan for nuclear reactor regulation was developed for the U.S. Nuclear Regulatory Commission by a Study Team of the Human Factors Society. This Study Team was selected by the Society to provide a balanced, experienced human factors perspective to the application of human factors scientific and engineering knowledge to nuclear power generation. The Study Team identified and analyzed areas of human factors concern in nuclear power generation. It reviewed and evaluated current and planned human factors activities and programs throughout industry and the Nuclear Regulatory Commission. The result was a recommended comprehensive human factors plan for the next ten years.
Quantitative Evaluation of Human Reliability for Operating Tasks in Nuclear Power Plants
Authors: Metwally A. Mohsen M. , Sabri Zeinab A. , Adams S. Keith , Husseiny Abdo A. 
Published: January 2012

Human reliability can be computed quantitatively provided that the operational data are put in the proper format and several information matrices are available. Both one dimensional and multidimensional trends can be easily determined by counting the number of operational errors that belong to one or more specific categories. Two examples are given for one dimensional trends in the operational tasks in 65 nuclear plants over a period of ten years. In the first example, the classification of events is made according to the cue used in error discovery. The results show that observation of unannunciated displays represents 41% of the total number of discovery cues. The second example shows that by classification of events according to the human failure mode, 50% of the total operation errors are due to omission. Recommendations and restrictions are given in detail. Assuming a constant failure rate (w.r.t. time) and an exponential human reliability model, failure rates (per hour and per demand of frequency of use) for valve mispositioning in two nuclear systems are computed. Comparison of the results obtained with other estimates of human error probabilities is made. Also, the results show that the unavailability of valves in those systems where human errors involved mispositioning is not significantly greater than that due to mechanical causes.
Development of Sensitive Performance Measures for Selection of Crews for Flight Training
Authors: Connelly Edward M. , Shipley Brian D. 
Published: January 2012

Performance of operator controlled systems is limited by our ability to measure system and component subsystem performance in a reliable and sensitive manner. Without adequate performance measures, there is no way to produce and test system designs, plan and execute training systems, or evaluate operational systems. Methods of developing these performance measures can be characterized by the way in which performance criteria are obtained. One approach which can be used when all factors that limit performance are known and quantified is an analytical method. For example, if a problem requires that an aircraft climb to a specified altitude while conserving fuel during the climb, the criterion, i.e., minimization of fuel, could be precisely defined analytically. Frequently, however, problems cannot be solved analytically, but demonstrations of superior as well as less than superior performances are available. In these cases an empirical approach can be used. This paper describes an empirical method for analyzing simulator flight data to develop weightings that permit performance discrimination between two groups of student pilots (one group of students successfully passed the initial Army rotary wing training program at Ft. Rucker, Alabama. The other group of students did not pass that training course.). The paper provides a description of the job sample (flight training) tests used to collect the data, the method for synthesizing the performance measures, and the results from using the measures to score student pilots.
Visual Simulation Requirements for Aircraft Aspect Recognition at Real World Distances
Authors: Kennedy Robert S. , Collyer Stanley C. , May James G. , Dunlap William P. 
Published: January 2012

A research program is underway whose goal is to provide engineering guidelines on target image sufficiency for training tactics and maneuvering skills in ground based flight simulators. A preliminary experiment was carried out in the Naval Training Equipment Center's Visual Technology Research Simulator (VTRS), using computer-generated aircraft images displayed on a dome via a variable-resolution target projector. The experiment examined aspect recognition sensitivity, or the distance at which subjects could determine the orientation of another aircraft. For our initial effort, the aspect (orientation) recognition task was simplified in the following ways: a) on each trial one of only 16 stationary target orientations of a TA4J aircraft was presented, b) targets had the same length/width ratio; c) subjects made binary up/down judgments; d) a staircase method provided thresholds for aspect recognition range. Four different target luminances, and three background luminances were combined with four different levels of projector resolution in a partial parametric study to assess the relative effects of contrast, resolution and brightness. All main effects were found to be significant. Over the ranges studied, contrast accounted for the most variance and brightness the least. In the best condition studied, aspect recognition was performed successfully at >4 miles (a 5.5 arc minute target), whereas the most degraded condition showed thresholds at 1.5 miles (a 14 arc minute target). These are comparable to distances known to be required in outdoor training ranges and in combat. An additional finding is that reliable subject differences were substantial (>20% of the total accounted for variance). The four subjects who were tested in this study had normal or better vision by static and dynamic tests of contrast sensitivity. Individual differences in these subjects' contrast sensitivity scores were predictive of their visual performance on this target aspect recognition task. These data are discussed from the standpoint of the utility of this paradigm for providing guidelines for training equipment design.