bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and Identification of Paracetamol Metabolites
Authors: Andrews R S , Bond C C , Burnett J , Saunders A , Watson K
Published: July 2017

A comparison has been made of the urinary metabolites of volunteers who had taken therapeutic doses of paracetamol with those of persons who had taken an overdose in an attempt to highlight the metabolic changes associated with massive doses.

The main technique for examining urine samples was two-dimensional thin layer chromatography. Other chromatographic techniques were used for the isolation and purification of metabolites.

The urinary metabolites after a therapeutic dose of paracetamol were identified as free paracetamol, paracetamol sulphate, 3-hydroxy-paracetamol-3-sulphate, 3-methoxy-paracetamol sulphate, paracetamol glucuronide, 3-methoxy-paracetamol glucuronide, paracetamol 3-cysteine conjugate and paracetamol 3-mercapturate.

The same metabolites were also present in urine following overdosage but the proportions were quite different. There was particularly a big increase in the relative amounts of cysteine and mercapturic acid conjugates excreted. No new metabolites were found.

The significance of these findings is briefly discussed in relation to the metabolism and toxicology of paracetamol.
A Theoretical Approach to the Management of Paracetamol Overdosage
Authors: Penn R G
Published: July 2017

Possible ways of treating paracetamol hepatotoxicity are briefly reviewed. This toxicity appears to be due to an oxidation metabolite which is normally detoxified by conjugation with glutathione, but when in excess, as in paracetamol overdosage, binds covalently to hepatic proteins to cause liver necrosis. Depletion of hepatic glutathione may also lead to other contributory disorders of cellular metabolism.

Physical methods of preventing this would appear to be of little value, and treatments are being developed which aim to lessen the production of the toxic metabolite, antagonize its attachment to hepatic tissue or to combat this toxicity via basic cellular mechanisms.

At this moment the most effective substances appear to be glutathione precursors and other compounds which interfere with oxidation of paracetamol.
Net Shape Woven Fabrics—2D and 3D
Authors: Clarke Steven R.
Published: July 2017

Weaving technology has been used for many years to weave net shape products to very tightly controlled dimensions. Numerous examples of narrow tapes, tubular fabrics, and multi-layer belting products can be found in the biomedical, automotive, and industrial fields. In more recent times 2D and 3D woven net shape products have expanded into polar or spiral woven fabrics, integrally stiffened skin panels, and tapered net shape airfoil components.

This paper will review the manufacturing technologies used to produce these net shape textile products as well as show examples of the finished textile products and their applications.
The Influence of Plasticizer Content and Type on the Rheological Behaviour of Plastisol Used in Coated Fabrics
Authors: Zadhoush A. , Alsharif M. A.
Published: July 2017

Coating pastes need to have very specific rheological properties because of the methods in which they are applied. Composition of the paste can be formulated in such a manner to achieve the desired rheological behaviour. In this research work rheological measurements of paste with nine various plasticizer content using DOP and DOA, and PVC-E with three k-values (69, 70, 75) were studied.

The results indicate that pastes are characterized by a non-Newtonian pseudoplastic flow under the studied conditions. The power-law index ( n) values of the pastes show that the flow properties of pastes change to Newtonian flow above 50 phr plasticizer content.

It was also found that the consistency index (k) of the pastes were decreased with increasing plasticizer content. Statistical analysis carried out show very good correlation between the studied parameters.
Practical Environmental Solutions to Solvent Coating Processes
Authors: Brodhead Donald J.
Published: July 2017

This paper will highlight various methods utilized for environmental compliance with solvent coating and laminating applications. Discussion will summarize the recovery and oxidation alternatives, including a brief overview of the advantages and disadvantages. The paper concludes by focussing on more specific examples of solutions, including capture hooding and enclosures, dryer air flow schemes, thermal oxidation integration, and use of secondary heat recovery for return energy to the drying process.
Designing Speech Displays for Telephone Information Systems
Authors: Herlong David W. , Williges Beverly H.
Published: July 2017

This study used a computer-driven telephone information system as a real-time human-computer interface to simulate applications where synthetic speech is used to access data. Subjects used a telephone keypad to search though an automated department store database to locate and transcribe specific information messages. Because speech provides a sequential and transient information display, users may have difficulty navigating through auditory databases. One issue investigated in this study was whether the alternate use of male and female voices to code different levels of the database would improve user search performance. Other issues investigated were the basic intelligibility of these male and female voices as influenced by different levels of speech rate. All factors were assessed as functions of search or transcription task performance and user preference. Analysis of transcription accuracy, user search efficiency and time, and subjective ratings revealed an overall significant effect of speech rate on all groups of measures but no significant effects for voice type or coding scheme. Results were used to recommend design guidelines for developing speech displays for telephone information systems.
The Effects of Recognition Accuracy and Vocabulary Size of a Speech Recognition System on Task Performance and User Acceptance
Authors: Casali Sherry P. , Dryden Robert D. , Williges Beverly H.
Published: July 2017

The purpose of the present study was to determine the effects of recognizer accuracy and vocabulary size on system performance of a speech recognition system. Subjects, ranging in age from 20 to 55 years, performed a data entry task using a simulated speech recognizer which simulated three accuracy levels and three levels of available vocabulary. Task completion times and subjective measures of acceptability were recorded. Results indicated that the accuracy level at which the recognizer was performing significantly influenced the task completion time and the user's acceptability ratings. Vocabulary size also significantly affected task completion time, however, its affect on the acceptability ratings was negligible. Older subjects in general required longer times to complete the tasks, however, they consistently rated the speech input systems more favorably than the younger subjects.
Gerontechnology®, Fitting Task and Environment to the Elderly
Authors: Graafmans Jan A. M. , Bouma Herman
Published: July 2017

Gerontechnology includes the research and development of techniques and technological products, based on the knowledge of aging processes, for the benefit of a preferred living and working environment and adapted medical care for the elderly. Physical and mental fitness are prerequisites to the satisfactory performance of daily tasks. Functionality decreases when perceptive motor abilities or skills diminish, when task demands are too high and/or when the product characteristics, the user-interface or the environmental conditions are in conflict with human skills. The introduction emphasizes the difference between approaching the elderly as patients or consumers. A concept of social interaction and active participation is described. It is discussed which support can be offered by technology and what the state of the art in gerontechnology is.
Use of Automated Telephone Reminders to Increase Elderly Patients' Adherence to Tuberculosis Medication Appointments
Authors: Tanke Elizabeth Decker , Leirer Von O.
Published: July 2017

Elderly patients (N=617) with scheduled appointments in a public health clinic tuberculosis clinic either received or did not receive an automated telephone reminder the evening before their appointment. Patients in this population were primarily non-English speaking immigrants who received reminders in their own language. Automated reminders decreased nonadherence 21% (from 29% to 23%), and this impact did not differ across ethnic groups.
Isolating Risk Factors for Crash Frequency among Older Drivers
Authors: Ball Karlene , Owsley Cynthia , Roenker Daniel , Sloane Michael
Published: July 2017

By the year 2024, 25% of drivers in the U.S. will be over the age of 65. Older drivers have more crashes and fatalities per mile driven than any other adult age group. Although driving is a highly visual task and vision impairment is more prevalent in the elderly, previous research has failed to identify visual factors which are strongly associated with increased crashes in the elderly. Using a comprehensive approach to assess several aspects of visual processing in a large sample of older drivers, this study has identified a measure of visual attention that had high sensitivity (89%) and specificity (85%) in predicting which older drivers had a history of crash problems, a level of predictability unprecedented in research on crash risk in older drivers. The “useful field of view”, as it is called, measures the spatial area within which an individual can be rapidly alerted to visual stimuli. Older adults with substantial shrinkage in the useful field of view were six times more likely to have incurred one or more crashes in the previous five year period. By comparison, visual sensory function, cognitive status, and chronological age were poor predictors of crash involvement. This study suggests that policies which restrict driving privileges based solely on age or on stereotypes of age-related declines in vision and cognition are scientifically unfounded. With the identification of a visual attention measure highly predictive of crash problems in the elderly, decisions on the suitability of licensure in the older adult population can be based on objective, visual-performance-based criteria.
Developing Interactive Guidelines for Software User Interface Design: A Case Study
Authors: Philips Brian H.
Published: July 2017

There have been numerous methodologies, models, and tools created to support successful user-system interface (USI) design. One such tool is USI design guidelines, which is important for both software developers and human factors professionals in developing a good user interface. This paper discusses the creation of interactive USI design guidelines intended for software developers to use when creating applications in the Microsoft® WindowsTM graphical software environment. User-system interface design guidelines are an important part of the software design process and complement other human factors activities that support good USI design. Differences between printed and on-line guidelines documents suggest developing on-line guidelines to support the development of WindowsTM-based GE Information Services applications. The content of the GE guidelines is tailored toward company applications, using examples of both good and bad user interface designs to illustrate guideline principles. The guidelines also include a sample application that incorporates the guidelines in its user interface. Components that contribute to the effectiveness of the guidelines, such as quality, time required to use, relevance, and complexity, are explored.
A Participatory Design Technique for High-Level Task Analysis, Critique, and Redesign: The CARD Method
Authors: Tudor Leslie Gayle , Muller Michael J. , Dayton Tom , Root Robert W.
Published: July 2017

CARD (Collaborative Analysis of Requirements and Design) is a participatory technique for analyzing task flows and for redesigning task flows, in software systems. It provides a macroscopic complement to the more microscopic design activities that are supported by the PICTIVE technique. CARD uses the metaphor of a card game as the vehicle for communication and collaboration among users, developers, and designers. We describe the technique, and provide illustrative session protocols and assessment data. The paper closes with a comparison to other relevant participatory practices, and a discussion of CARD's shortcomings.
Are We Overlooking Some Usability Testing Methods? A Comparison of Lab, Beta, and Forum Tests
Authors: Smilowitz Elissa D. , Darnell Michael J. , Benson Alan E.
Published: July 2017

We compared the effectiveness of Lab testing, Beta testing, and Forum testing at identifying software usability problems. Thirty participants were involved in the experiment, with ten participants in each of the three test conditions. The Lab test involved participants performing prescribed scenarios with the software in a controlled Lab environment, while human factors engineers recorded participant's problems. The Beta test method had participants use the software in their own environment to perform their real world work, and record their own problems. The Forum test was similar to the Beta test, except that the software was made available on a company-wide computer bulletin board and the participants selected themselves. Findings show that the Beta test method was as effective as the Lab test method in the number of problem types identified. The Lab test uncovered a larger proportion of serious usability problems than did the Beta test. The Beta test method was the most cost-effective method. The Forum test method found the fewest number of problem types, and was the least cost-effective. Thus, the results of this study broaden the current literature by showing that the Beta test method may be a cost-effective alternative to the traditional lab test.
An Exploration in the Design Space of Three Dimensional Hierarchies
Authors: Chignell Mark H. , Poblete Ferdie , Zuberec Sarah
Published: July 2017

Three dimensional hierarchies may be used to visualize and manipulate a variety of types of information, including tables of contents, taxonomies, fault trees, and code libraries in languages such as C++. Based on a review of the literature, it is suggested that visual scanning and perceived organization are two main processes involved in the understanding and use of 3D hierarchies. A general system (Info-TV) is described which can be used to explore a 3D design space. Info-TV is an information tree visualization system that takes hierarchical information and displays it in a three dimensional format. It has been designed to include the major parameters of the tree visualization design space and can be used to explore this space. Two experiments are reported that assess the effect of different tree shapes on different tasks. The results of these experiments are then discussed in terms of their implications for the design space of three-dimensional hierarchies.
VDT Positions: Effect on Performance and Comfort
Authors: Lu H. , Aghazadeh F.
Published: July 2017

This study investigated the effect of VDT vertical position on operator's performance and comfort. Three VDT positions (center of the screen) were studied: eye level, 250 mm above eye level, and 250 mm below eye level. At each VDT position, subjects worked with the computer continuously for 35 minutes. Typing speed (words per minute) and accuracy were recorded. A questionnaire about physical discomfort was answered by each subject after the trial at each VDT position. The result indicates that placing the center of the VDT at eye level is more comfortable.
Two Classes of Problem Solving Situations in Managing Complex Systems
Authors: Xiao Yan , Milgram Paul , Doyle D. John
Published: July 2017

Previous studies in complex domains such as power plants and air traffic control have described a wide range of behaviours not addressed by traditional psychological studies. This led to a field study of problem solving in anaesthesiology, using various methods of collecting behavioural data directly from the field while anaesthesiologists were doing their job. The methods used include direct observation, interviewing, and on-line verbal protocol recording with thinking aloud verbalisation.

This paper describes findings from the field study and presents an analysis of how problem solving situations arise during the management of anaesthesia, a task similar to process control. Two classes of problem solving situations are identified: (1) managing the patient during non-critical but stressful and long lasting incidents—problem solving is characterised by competing goals and multiple hypotheses, and the memory load while keeping track of what is in the ‘pipeline’; (2) deploying preventive and preparatory strategies—the problem solving is characterised by feedforward control of system (patient) status in the face of anticipated inputs to the patient, preparation of preconditions of necessary and contingency procedures, and anticipation of troublesome situations to be avoided. A categorisation scheme is proposed to classify problem solving situations according to how they arise: incident-induced and strategy-induced.
The Scientific Basis of Human Factors - A Behavioral Cybernetic Perspective
Authors: Smith Thomas J.
Published: July 2017

This report summarizes a body of empirical evidence supporting the conclusion that the preponderance of variability in human behavior and performance is attributable to design factors in the performance environment. This may be considered the central doctrine of human factors science that establishes the scientific basis of human factors as an integral discipline. The report goes on to offer a conceptual interpretation, based on behavioral cybernetic theory, of how and why design factors influence human behavior and performance. [This is not an official Bureau publication. The views expressed are not necessarily those of the U.S. Bureau of Mines.]
Auditory Displays: If They are so Useful, Why are they Turned Off?
Authors: King Robert A. , Corso Gregory M.
Published: July 2017

Pilots often turn off the auditory displays which are provided to improve their performance (Weiner, 1977; Veitengruber, Boucek, & Smith, 1977). The intensity of the auditory display is often cited as a possible cause of this behavior (Cooper, 1977). However, the processing of the additional information is a concurrent task demand which may increase subjective workload (Wickens & Yeh, 1983; McCloy, Derrick, & Wickens, 1983). Pilots may attempt to reduce subjective workload at the expense of performance by turning off the auditory display.

Forty undergraduate males performed a visual search task. Three conditions: auditory display on, auditory display off, and subject's choice were run in combination with nine levels of visual display load. The auditory display, a 4000 Hz tone with a between-subject intensity of 60 dB(A), 70 dB(A), 80 dB(A), and 90 dB(A), indicated that the target letter was in the lower half of the search area. NASA-TLX (Task Load Index) was used to measure the subjective workload of the subjects after each block of trials (Hart & Staveland, 1988).

A non-monotonic relationship was found between auditory display intensity and auditory display usage. Evidence was found that the auditory display increased some aspects of subjective workload– physical demands and frustration. Furthermore, there was a dissociation of performance and subjective workload in the manner predicted by Wickens – Yeh (1983). The implications of these results for display design are discussed.
A Test of Fitts' Law in a Dual-Task Paradigm
Authors: Shehab Randa L. , Schlegel Robert E.
Published: July 2017

A simulated automobile driving environment was used to assess the validity of Fitts' Law under dual-task conditions. An aimed hand movement task was used as the Fitts task representative of reaching for controls on an instrument panel. The task required activation of one of four touch-sensitive response plates upon recognition of an auditory stimulus. Movement difficulty was manipulated by varying target location and size. Target location was examined at four levels corresponding to position in a 2 × 2 array. Distances of the targets from the two-o'clock position on the steering wheel ranged from 27 cm to 53 cm. The target plates were square and measured 1.27 cm (1/2 inch) or 0.64 cm (1/4 inch) along the side. The eight combinations of movement amplitude and target size yielded seven unique levels of Fitts' Index of Difficulty (ID) ranging from 5.4 to 7.4. The movement task was performed alone and in combination with two other tasks to create three levels of task loading. A display monitoring task was used to represent the visual demands of driving while an unstable tracking task was used to represent the perceptual-motor demands of driving.

Following adequate training, ten subjects performed three replications of six task conditions (three loading levels x two target sizes). Within each replication, the order of testing was counterbalanced across subjects. The dual-task visual loading condition involving the movement and monitoring tasks consistently resulted in the longest reaction times. The dual-task perceptual-motor loading condition involving the movement and tracking tasks resulted in consistently longer movement times. Fitts' ID had a significant effect on both reaction time and movement time for all three conditions of task loading. However, separate linear regressions of movement time on ID for each task loading level resulted in R2 values of 0.66 to 0.82. Multiple linear regressions involving target size and movement amplitude as predictor variables provided better predictions with R2 values of 0.90 to 0.93. The regression equations provided in this paper may be used by designers to estimate differences in response time due to control size and location.
Truck Driver Anthropometric Data: Estimating the Current Population
Authors: Kinghorn Rhonda A. , Bittner Alvah C.
Published: July 2017

This report shows that a challenge facing designers of commercial trucks and other vehicles is a lack of current operator anthropometric data on which to base design decisions. Specifically, it was points out that current data suffer from a number of limitations including secular size changes, ethnic and gender composition shifts, and excessive standard errors (S.E.) of percentiles estimates. These and other limitations point out the need for estimates of contemporary, professional driver anthropometry. This report presents tabulations of comprehensive male and female driver population anthropometry estimates, and outlines a method for applying these anthropometric data to the design of trucks and other vehicles.
Vertical Eye Positions in Heavy Trucks
Authors: Reynolds S. H. , Bowers-Carnahan F. Renae
Published: July 2017

In the truck industry, the driver's eye location is represented by an ellipse. The specific ellipse used is defined by the Society of Automotive Engineers (SAE) and is called an “eyellipse.” A preliminary study investigated whether an observed difference between the design eyellipse and the actual driver eye positions is significant.

A sample of five drivers was selected based on anthropometric dimensions. The eye positions of the drivers were measured in a static production vehicle. The results indicated that the sample population mean was significantly higher (at the α = 0.01 level) than the design eyellipse centroid. Several potential causes for the demonstrated difference are discussed. Further studies should be conducted to verify the results of this study to determine whether the eyellipse equations or procedure need to be modified.
The Influence of Operational Conditions on Driver Fatigue in the Long Distance Road Transport Industry in Australia
Authors: Feyer Anne-Marie , Williamson Ann M.
Published: July 2017

The present study is the second part of a large project designed to identify possible strategies to better manage driver fatigue in the long distance road transport industry. The first study in the project, reported elsewhere, investigated driver fatigue among truck drivers. The present study examined driver fatigue in the passenger sector. The questionnaire used earlier was adapted for the passenger sector to collect information about the drivers' experience of fatigue, working conditions, type of driving operation as well as details of their last trip and last working week. The results revealed that the experience of drivers in the passenger sector only partially overlapped with those for the truck sector. The ways in which fatigue occurred and some of the contributors to fatigue showed remarkable consistency across sectors. There was major divergence, however, in the ways drivers reported managing fatigue.
A Simulator Evaluation of Advance Flagger Signs
Authors: Alicandri Elizabeth , Walker Jonathan
Published: July 2017

An interactive driving simulator was used to compare two versions of a construction and maintenance advance flagger sign, designed to alert motorists to the presence of a flagger in a work zone ahead. The standard symbol is a silhouetted figure holding a flag, the revised symbol is a silhouetted figure holding an octagonal paddle. Forty subjects participated in a simulated drive in which one of the two signs was encountered, along with a variety of other highway signs. The study found no significant differences between the two signs in terms of driver behavior in the presence of the signs. A post-drive questionnaire showed significant advantages for the standard sign. Drivers exposed to the standard sign had significantly better recall of which sign they had encountered. Measures of sign comprehension, both in terms of meaning and required actions also showed the superiority of the standard sign. Subjects were more likely to correctly identify the standard sign as appearing in construction zones, and the standard sign was more preferred than the revised sign.
A Young Driver Research Program Based on Simulation
Authors: Triggs Thomas J , Drummond Alan E
Published: July 2017

The Monash University Accident Research Centre is conducting a comprehensive research program with a focus on young driver performance issues. Despite the failure to develop effective young driver risk reduction strategies, most research efforts continue to be directed towards the behaviour and/or motivation of young drivers. This paper suggests that an expansion of this effort to include the investigation of driving performance issues is warranted. To this end, the simulator-based research effort is described, the cornerstone of which is an attempt to identify the important differences in driving performance as a function of driving experience. In addition, an overview of specific investigations in the areas of attention switching time and the provision of decision aiding information is given.
Communication between Crews: The Effects of Speech Intelligibility on Team Performance
Authors: Whitaker Leslie A. , Fox Starr L. , Peters Leslie J.
Published: July 2017

Speech is a critical method of communication among group members while they are trying to accomplish a task. The present research program is designed to determine the impact of speech communication on performing a variety of communication-intensive tasks. A model describing performance as a function of auditory workload has guided this research. This model states that transmission, linguistic, and individual factors each contribute to auditory workload and hence influence task performance. The current study focused on two transmission factors: speech intelligibility and communication structure. Previous work in this program has reported the performance of two- or three-person crews operating alone to accomplish various tasks. The present study examined the team performance of two crews operating interactively to accomplish more complex tasks. Speech intelligibility was varied from 100% to 25% and was measured using the Modified Rhymes Test. Twelve crews were tested at the Closed Combat Test Bed using M1A2 tank simulators. The results of this study are consistent with those predicted by the auditory workload model; decrements in task performance occur at higher levels of intelligibility for more complex tasks than for less complex tasks. In addition to the task performance measured in this study, verbal protocols taken from recorded transcripts were coded as evidence of the changes in communication structure when speech intelligibility is varied. The implications of these findings for communication using cellular telephones and radio communication are discussed.
Dynamics of Trunk Performance during One-Handed Lifting
Authors: Allread W. Gary
Published: July 2017

This study investigated the biomechanical effects of using one hand to perform a materials handling task. Subjects were asked to lift a box from a lower to an upper platform using either one or two hands. Three weight levels and four lower platform positions were examined. Subjects wore a back monitor (from which was calculated motion components in the three cardinal planes of the body), stood on a force plate, and were asked to give a rating of perceived exertion for each lift. Results of this study showed that one-handed lifts produced significantly higher ranges of lumbar spine motion in the lateral and transverse planes and greater flexion in the sagittal plane. Back motion risk factors previously found to be associated with high risk of injury jobs all were significantly higher for one-handed lifts. Two-handed lifts, however, produced overall faster motions in the sagittal plane, and equal or larger acceleration and deceleration magnitudes in all planes of motion. Results from the psychophysical measure found no differences in perceived exertion between one- and two-handed lifts. These results suggest that one-handed lifts load the spine more than two-handed lifts due to the added coupling and increase one's risk of suffering a low back disorder. This study also agrees with previous research finding that increased load weight and lifting from asymmetric positions increase risk of low back injury.
A Catastrophe Theory-Based Model for Quantification of Risk of Low Back Disorders at Work
Authors: Karwowski Waldemar , Marras William S.
Published: July 2017

This paper discusses applications of the catastrophe theory in the dynamic modeling of occupational low back disorders, and offers a framework for conceptualization of such disorders in view of the elementary cusp catastrophe models. It was proposed that low back disorders due to manual lifting should be considered as a discontinuous phenomenon, reflecting dynamic changes in the state of human musculoskeletal system, which are dependent upon the combination of human strength abilities, muscular fatigue and endurance, spinal loading tolerance, as well as dynamic equilibrium between these variables. The behavior of the proposed cusp-catastrophe based model for the risk of LBDs due to manual lifting jobs was examined based on empirical data collected in industry.
Use of the Actigraph for Objective Quantification of Hand/Wrist Activity in Repetitive Work
Authors: Grant Katharyn A. , Galinsky Traci L. , Johnson Peter W.
Published: July 2017

Valid and reliable measures of hand/wrist activity are needed to address the relationship between work tasks and the development of upper extremity musculoskeletal disorders. The utility of the actigraph for measuring wrist activity in manual work was examined in this study. Ten grocery cashiers and four non-cashier retail workers wore actigraph monitors on both wrists and the left ankle during their normal work activities. Work activities were periodically observed and recorded on videotape. Data recorded by the actigraphs were matched against observational data. The results indicated that actigraphy was effective in detecting significant work-related variations in physical activity in the three limbs studied. Compared to traditional observational procedures, actigraphy represents a cost-effective approach for obtaining objective and quantitative information about the intensity and duration of work over long time periods. Traditional observational procedures, however, are necessary to provide additional information needed for a complete job analysis (e.g., postural data). Continuous activity recordings can be used in conjunction with sampling protocols to examine the relationship between work-related physical activities and musculoskeletal trauma.
Maximum Lifting Capacity in Single and Mixed Gender Three-Person Teams
Authors: Sharp Marilyn , Rice Valerie , Nindl Brad , Williamson Tania
Published: July 2017

Little information is available regarding isoinertial lifting ability in teams of two or more people. The relationship between the sum of individual lifts and the lifting capacity of a three person team was examined. Eleven men' and ten women were randomly combined into 18 teams for each of the following four combinations: three men (3M), three women (3W), two men with one woman (2M&1W), and one man with two women (1M&2W). While the absolute load lifted from floor to knuckle height decreased with a decrease in the number of males on the team, team lifting strength as a percentage of the sum of individual lifting strength was generally higher for single gender teams (91.0% for 3W and 85.0% for 3M) than for mixed gender teams (82.7% for 1M&2W and 74.4% for 2M&1W).
Evaluation of Limiting Strength Constraints in a Comprehensive Biomechanical Model
Authors: Kerk Carter J. , Chaffin Don B.
Published: July 2017

The strength constraints in a two-dimensional static human force exertion capability model (HFEC) have been evaluated using eight male and female subjects of varying anthropometry and strength capability. The model comprehensively estimates feasible exertion capability under symmetric conditions using a set of fifteen linear constraint equations from three constraint classes: strength, stability, and coefficient of friction (COF). This evaluation examines the nature of the limiting strength constraints. The computer model aided in designing tasks (combining posture with force exertion direction) that isolated upper extremity strength constraints and hip/torso strength constraints from stability and COF constraints. Subject performances of maximum exertions were recorded using force platforms and a multi-axis load cell to record external reaction forces at the hands and feet. Body posture was recorded with a 2D motion analysis system. The observed hand force exertions were compared to the exertions predicted by the model. The identity of the limiting constraints was well predicted by the model. The location of the constraints was logical and predictable. The results are discussed in the context of other modeling approaches as well as implications for future research. The HFEC approach shows excellent potential as an ergonomic engineering tool for teaching, evaluation, and design.
PVAT - a Video Analysis Tool for Microgravity Posture Evaluation
Authors: Whitmore Mihriban , Merced-Moore Darlene , Adam Susan C.
Published: July 2017

PVAT (Posture Video Analysis Tool) has been developed to meet the special needs of ergonomist and human factors analyst attempting to evaluate microgravity working posture from video footage. These specialists often have very little or no control over the video coverage. Moreover, the majority of Shuttle mission videos are not recorded for quantitative analysis. The purpose for developing PVAT is to provide a structured methodology in which these specialists could optimize the data collection technique. PVAT is specifically designed to document microgravity postures using videos of astronauts working in a space environment. The primary focus of PVAT is identifying the microgravity working postures and relating them to design issues in the workplace. This tool is currently an interactive software prototype written in SupercardTM. Users are provided with a set of input parameters such as: subject code, body orientation, targeted body part, camera view (given subject location), body movement, and rating level. A secondary set of inputs are also available which provides the ability to document extraneous behaviors or activities such as bending, reaching and interruptions. The tool allows for the input parameters to be customized as needed. Once the setup is defined, the user begins documenting the target posture and/or behaviors. The paper will discuss PVAT, its space applications and plans for its use.
The Influence of Anti-Fatigue Mats on Back and Leg Fatigue
Authors: Stuart-Buttle C. , Marras W. S. , Kim J. Y.
Published: July 2017

Prolonged standing is common in many industrial workplaces. It is also quite common for workers to complain of discomfort in the back and legs as a result of prolonged standing. Mats are often provided for the worker to relieve this fatigue. However, there is no quantitative evidence that these mats relieve leg and back fatigue. Five subjects were asked to stand on a concrete surface and two mat surfaces for prolonged periods of time. Spectral electromyo-graphic (EMG) analyses indicated that mats reduce localized muscle fatigue in the erector spinae muscle only. Furthermore, this fatigue reduction occurred only with the more com-pressible of the two mats tested. These results imply mat localized muscular fatigue in the leg may not be relieved with “anti-fatigue” mats and some of these mats only benefit the back.
Round Reaction Forces during Miner Cable Pulling Tasks
Authors: Hamrick Christopher A. , Gallagher Sean , Redfern Mark S.
Published: July 2017

The handling of mining machine cables in underground coal mines has been identified as a particularly stressful task and is a likely contributor to low back pain. In this experiment, seven experienced miners performed a cable pulling task while ground reaction forces and cable tension were measured. The independent variables were two levels of cable resistance (low and high) and lifting conditions (kneeling under a 1.2 meter [48 inch] roof, stooping under a 1.2 meter [48 inch] roof, stooping under a 1.5 meter [60 inch] roof, and unrestricted standing). The dependent variables were the peak values of the following: actual tension measured in the cable, ground reaction forces in the X (anterior), Y (lateral), and Z (vertical) directions and the magnitude of the resultant force vector. Work posture significantly affected the peak ground reaction forces in the Y-direction. The Y-forces were highest in the kneeling condition, indicating that there is less postural stability when performing cable pulling tasks in a kneeling posture. Thus, there may be a greater likelihood of injury in this posture. Additionally, biomechanical stresses which contribute to musculoskeletal injury may be greater in the kneeling posture.
The Effects of Obstructions on Arm Movement Time during Reach and Positioning Movements of a Simulated Maintenance Task
Authors: Taylor Susan A. , Strybel Thomas Z.
Published: July 2017

The purpose of this study was to investigate the fundamental issue of how an obstruction affects movement time during reach and positioning components of a simulated maintenance task. Eight obstruction locations for two target locations provided the experimental manipulation for the study, while movement time was measured as the dependent variable. Data for all the trials were obtained using a three-dimensional magnetic sensing device placed on the back of the subject's hand as he/she moved in space from the starting point to the target in a wooden mockup replicating the work space of a maintainer in an aircraft horizontal stabilizer. Results indicated that movement times increased when the vertical position of the obstruction was within roughly 5.72 cm of the target. Subjects' perceived difficulty in those conditions with longer movement times was attributable more to the inability to see the target during the end of the motion than the lack of positioning space around the target. These findings emphasize the role visual feedback played in a task of this type, and its effect on maintenance procedure times in general.
An Evaluation of Workstation Adjustment and Musculoskeletal Discomfort
Authors: Halpern Craig A. , Davis Paul J.
Published: July 2017

Ninety (90) office workers were administered a survey to gather a subjective evaluation of appearance, layout, useability and efficiency of their workstations, and to develop a body part discomfort rating. All ninety workstations were then reconfigured and adjusted to fit each user's anthropometric dimensions. After approximately four months, a follow-up survey was conducted. Results from the reconfiguration and “fitting process” indicated a significant decrease in body part discomfort, and an increase in the perceived efficiency, and useability of the office furniture and equipment. Use of office equipment properly adjusted to fit the user through ergonomics and anthropometric principles may enhance productivity and performance, reduce awkward postures, and the associated cumulative trauma injuries.
Developing the User-System Interface for a Communications System for ALS Patients and Others with Severe Neurological Impairments
Authors: Murphy Robert A. , Basili Annamaria
Published: July 2017

In developing a computerized communications system for the severely neurologically handicapped, the user-system interface required adaptation to the special limitations of this population. The needs of health care workers, who assist the patient in the use of Blink-writer, were also addressed as part of the system design.
Growing a Styleguide: Macroergonomic Strategies for Achieving Consistent User Interface Design
Authors: Root Robert W.
Published: July 2017

Consistency in user interface design is generally recognized as a desirable goal. The main problem facing most practitioners is how to achieve it. In many cases the solution begins with a user interface styleguide that defines the design criteria for user interface developers. A styleguide is a necessary, but not sufficient, part of the solution. In practice, achieving consistency requires a multi-faceted approach ranging from design guidelines to organizational structures and processes. This paper discusses macroergonomic aspects of styleguide development in a large software development organization, focusing on the processes and organizational strategies used to develop content and achieve initial buyin by user interface designers and developers.
The Resurrection of Span of Control
Authors: Wenzel Brenda M. , Christ Richard E.
Published: July 2017

Operating environments have been undergoing unique changes that are causing management to reexamine factors that impact organization design. In attempting to respond to this design challenge, it became clear that there is a need for high quality empirical research directed at the organizational concept of span of control (SOC). The concept of SOC refers to the number of subordinates that one leader can effectively command and control. The purpose of this research paper is to summarize the outcome of a comprehensive analysis of the literature relevant to SOC and to discuss research issues on this topic. Six interrelated factors emerged from the literature review as important in determining a leader's proper SOC. The critical factors are tradition, environmental uncertainty, level of technology, subordinate's task characteristics, leadership behavior, and leader's workload. A research program is being developed to investigate these six factors with the goal of establishing a theoretical groundwork for the concept of SOC. Additionally, democratization as a design principle is introduced as an innovative approach to organization design.
At&T Image Analysis System Development for Manual Lifts
Authors: Ghahramani Bahador , Fleischer Lawrence B. , Congleton Jerome J. , Foster Joseph W.
Published: July 2017

AT&T Video Ergonomics Evaluator System (AT&T-VEE) is a state-of-the-art computer analysis system used to analyze the hazards of a Manual Material Handling (MMH) task. This project was funded and managed by the American Telephone & Telegraph Company (AT & T) and designed and developed at Texas A&M University. The system is a lifting analyses tool for the 1992 NIOSH Lifting Equation to determine minimal user effort in lifting an object and to standardize the outputs. This system is now capable of providing the AT & T safety specialists with clear access to: complete NIOSH analyses, pictures of the lift environment, and background information on the MMH process.

It was determined that a system, such as AT & T-VEE, was needed to reduce AT & T's MMH injuries and ensuing problems. The scope of the project was to develop a menu driven, user friendly system that would provide employees with the ability to determine the maximum weight of objects utilized at MMH tasks. In order to perform a lifting analysis, a video tape of a manual lift is first produced. The system user, in conjunction with a computer, enters employee's measurement landmarks and points of analyses, e.g., ankles, load center, weight, etc. AT & T-VEE produces a NIOSH Lifting Equation analyses, pictures and records of the MMH task.
Human Factors Research Recommendations for the Development of Design Guidelines for Advanced Traveler Information Systems
Authors: Dingus Thomas A. , Hulse Melissa C.
Published: July 2017

This paper describes the outcome of a comprehensive literature review specifically conducted to assess research relevant to the design of advanced traveler information systems (ATIS) for automotive and commercial vehicle use. The goal of the literature review was to identify existing human factors guidelines applicable to the design of ATIS and gaps in the research precluding the development of comprehensive human factors guidelines for ATIS applications. A summary of ATIS research findings and research gaps is presented. Through presentation of both research findings and research gaps, it is hoped that interest will be sparked and focus will be provided for researchers in this growing application of human factors. Given the criticality of ATIS applications (both in terms of driver safety and public acceptance) and the visibility that will be provided to the human factors community from participation in ATIS design, human factors research leading to comprehensive and usable guidelines is extremely important.
User Information Requirements for Intelligent Vehicle Highway Systems as a Function of Driver Category
Authors: Ng Linda , Barfield Woodrow
Published: July 2017

Advanced Traveler Information Systems/Commercial Vehicle Operations (ATIS/CVO) are segments of IVHS currently being researched as a means of decreasing road congestion and increasing safety. Due to the complex information requirements for these systems, three surveys have been designed by University of Washington researchers and distributed nationwide to collect these requirements from the users: commercial drivers, dispatchers and private vehicle drivers This paper discusses the methodology used to design the surveys and the effort to ensure that a representative sample was included on a nationwide basis. Approximately 8,300 surveys were distributed in person and 10,000 dispatcher surveys were distributed in a newsletter. Data estimation procedures will include modeling the influence of an in-vehicle system for route guidance and determining the significant impacts of an ATIS/CVO in terms of age, gender, income, and other socioeconomic characteristics.