bluuebunny/crossref_metadata_2025 huggingface dataset:
Acceptance of Advertising and Collection of Personal Information
Authors: Hurwitz Joshua B.
Published: October 2012

The current study investigated the relationship between acceptance of advertising and of services that collect personal information. Survey respondents were presented with a questionnaire asking about their agreement with various forms of advertising, and were also presented with scenarios describing mobile and TV-based services. The results showed that adding collection of personal information to the services had less of an impact on the ratings of respondents who were more accepting of advertisements inserted into applications (software, games and MP3s) or presented on mobile devices. These results suggest that acceptance of advertising could be an indicator of privacy sensitivity, and could be used to personalize privacy management in part based on individual differences in sensitivity.
Cognitive Approaches to Password Memorability – the Possible Role of Story-Based Passwords
Authors: Werner Steffen , Hoover Connor
Published: October 2012

The inverse relation between memorability of a password and the strength of a password presents a unique optimization opportunity for cognitive approaches. While graphical passwords have received most of the attention to date, the use of verbal material to create memorable passwords presents some distinct advantages that might make story-based passwords a serious contender in the race to the ultimate “cognitive” password system. In a first pilot study with 385 participants we investigated the memory for different story elements for short (10 min) and long (1 week) retention intervals. Even a non-optimized story yields better long-term performance than traditional alphanumeric passwords and is comparable to the lower end of graphical password systems.
Can User-Derived Gesture be Considered as the Best Gesture for a Command?: Focusing on the Commands for Smart Home System
Authors: Choi Eunjung , Kwon Sunghyuk , Lee Donghun , Lee Hojin , Chung Min K.
Published: October 2012

With advanced technologies of gesture recognition, various researchers have started to focus on deriving intuitive gestures for commands from users. Most of the studies suggested only the gestures with the highest frequency (a top gesture) for the commands. In this study, a total of two experiments were conducted to identify whether the top gestures in the first experiment are maintained in the second experiment. A total of thirty participants took part in the first experiment and twenty eight in the second experiment. As a result of the experiments, 65% of the top gestures from the first experiment were changed in the second experiment, although the same participants conducted the two experiments. Also, the agreement score was significantly higher in the second experiment.
“Commanding Your Robot” Older Adults’ Preferences for Methods of Robot Control
Authors: Beer Jenay M. , Prakash Akanksha , Smarr Cory-Ann , Mitzner Tracy L. , Kemp Charles C. , Rogers Wendy A.
Published: October 2012

Home robots have the potential to assist older adults in maintaining their independence. However, robots deployed in older adults’ homes will be required to interact with untrained, novice users. The way untrained users, such as older adults, provide commands or control the robot (i.e., “method of robot control”) will likely impact the ease of use and adoption of the robot. The current study explored older adults’ preferences for controlling robots. Twelve independently-living older adults (ages 68-79) observed a functioning personal robot in a home setting, and were interviewed about their opinions regarding specific methods of robot control (i.e., laser pointer, physical manipulation, and devices). The older adults perceived advantages and disadvantages of these specific methods, including ‘specificity in command’, ‘accurate robot performance’, ‘limitations in their own physical capability’, and ‘challenges in using control device.’ The older adults also completed a questionnaire measuring their willingness to use 10 different types of methods of robot control. These data revealed that older adults were willing to use a variety of methods. Although older adults were limited in their spontaneous ideas about robot control (i.e., limited to voice command), once exposed to other options they were willing and open to a variety of control methods.
Effects of Cover Letter Subject Line and Open-ended Question Response Area on Responding to an Internet Survey
Authors: Linegang Michael P. , Moroney William F.
Published: October 2012

To ensure the validity of the data and conclusions derived from internet questionnaires, researchers must understand the implications different questionnaire design decisions have for their data. This paper describes an internet-based survey in which the text of the email cover-letter subject line and the size of response area provided for open-ended question responses were manipulated. This study showed that the offer of a food incentive in the subject line yielded fewer responses. Meanwhile, a larger (six line) text box yielded significantly more words than a smaller (one line) text box, but the larger text box did not yield any increase in the number of topics addressed in the open-ended response data. Finally, open-ended questions soliciting negative comments yielded significantly more words than did questions seeking positive comments.
Participant Characteristics and Speeding Behavior during an Advisory Warning and Cash Incentive Intervention
Authors: Berlin Sharon , Reagan Ian J. , Bliss James P.
Published: October 2012

Speeding-related crashes are responsible for a significant economic and human toll to society. This paper presents data from a field study evaluating the effectiveness of in-vehicle automated feedback and monetary incentive systems to reduce speeding behavior. The current effort was a unique opportunity to compare self-reported speeding beliefs and behaviors to observed driving behaviors and quantify associations between participant characteristics and driving behaviors. Fifty participants completed the four week study within three experimental groups: automated feedback with monetary incentive (n=20), automated feedback without incentive (n=20), and control (n=10). Results indicated little connection between self-reported and observed speeding behaviors, despite high correlation between self-reported and observed driving patterns overall. Associations were found between sensation-seeking personalities and speeding behavior. Few differences were found between sexes. Results highlight the relationship between personality and driving behavior, and suggest a closing gap between male and female driving behaviors.
A Preliminary Research on P300-Based BCI Application for People with Motor Disabilities
Authors: Li Yueqing , Woo Jincheol , Nam Chang S.
Published: October 2012

The primary purpose of this paper was to find the relationship between the participants’ disability and user performance on a P300-based brain-computer interface (BCI) — P300 Speller. Ten participants with motor disabilities were employed to spell 10 ten-character phrases with two different user interfaces (5 for each). Results of the study indicated a linear relation between participants’ speech ability and task performance. As the speech ability increases, users’ task performance increases. However, such a relation doesn’t exist between motor ability and task performance. This study should provide invaluable empirical data and insights for the future study.
The Joint Effect of Task Characteristics and Extraversion on The Performance, Workload, and Stress of Signal Detection
Authors: Szalma James. L. , Teo Grace W.L.
Published: October 2012

The present study tests an extension of the Dynamic Adaptability Theory of Stress (Hancock & Warm, 1989) that incorporated individual differences into the model (Szalma, 2008). The purpose was to investigate how the task characteristics of information rate (event rate) and information structure (number of displays to be monitored) interact with participant personality (extraversion) to affect the performance, workload, and stress associated with a cognitive vigilance task. As expected, extraversion moderated the relationship of task characteristics to performance, global workload, distress, and task engagement, although the relationship of extraversion to the worry dimensions of stress was not significant.
The Effects of Individuals’ Mood State and Personality Trait on the Cognitive Processing of Emotional Stimuli
Authors: Lim Sol I. , Woo Jin C. , Bahn Sangwoo , Nam Chang S.
Published: October 2012

This study assessed the effects of individuals’ personality trait and mood state on affective reactions to emotional stimuli. Resting electroencephalographic (EEG) was recorded from 11 healthy right-handed males and questionnaires were administered to assess subject’s mood state (total mood disturbance score) and personality trait (i.e. introvert or extravert), respectively. Along with baseline signals from the resting period, EEG was measured while subjects viewed pictures of three types of emotional stimuli (negatively arousing, calm, and positively arousing) chosen from the International Affective Picture System (IAPS). A major question raised by the brain’s response to emotional stimuli was whether these changes were related to preexistent differences in subjects’ mood state and personality. Extraverted subjects and those with normal mood disturbance scores showed a greater response to positive stimuli processing while brain areas of introverted subjects and those with high mood disturbance scores were highly responsive to negative emotional pictures in the upper alpha frequency bands (10~12 Hz).
Predicting and Maintaining the Challenge Point through the Study of Individual Differences
Authors: Bryant Michelle R. , McLaughlin Anne Collins
Published: October 2012

Predicting a challenge point in performance requires an examination of individual differences in cognitive, perceptual and motor abilities. The following paper poses an approach to the previously established challenge point framework that integrates abilities in different populations while incorporating subjective workload and stress measures. Results will allow human factors and ergonomics to merge existing knowledge about these areas into several applications for real world performance success in a variety of tasks.
Investigating Individual and Occupational Factors and their Interactions on Low Back Pain Severity in Workers
Authors: Govindu Nirathi Keerthi , Babski-Reeves Kari
Published: October 2012

Low back pain (LBP) is the most prevalent work-related musculoskeletal disorder. Current ergonomic prevention strategies focus on reducing the effect of occupational risk factors. However, other underlying mechanisms may exist since not all workers performing the same task develop an injury. In this study, 36 LBP patients with a previous MRI scan were recruited to investigate the effects of individual and occupational factors and their interactions on LBP severity. Individual and occupational factors information was obtained through questionnaires. LBP severity ratings were obtained through a self-reported Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI) questionnaire and served as the dependent variables. Stepwise linear regression analysis was performed on the variables. For ODI, a model consisting of interaction effects between individual and occupational risk factors with an adjusted R2 value of 0.84 was obtained. These preliminary results may help to develop models to predict and, hence, prevent chronic LBP.
Fine Distinctions within Cognitive Style Predict Forecasting Accuracy
Authors: Poore Joshua C. , Regan John , Miller Sarah , Forlines Cliff , Irvine John
Published: October 2012

Leveraging data from over 1,000 users in the System for Prediction, Aggregation, Display and Elicitation (SPADE) research program, we present preliminary data on the factor structure of individual variation in decision making ability and the associations of this variance with errors in cognitive reasoning and accuracy in making socio-political forecasts. Generally, prior research has identified two factors, or styles—intuitive and analytic—that account for significant variance in how individuals reach solutions to complex numerical and logical problems. Though sometimes named differently across research programs, an intuitive style is a tendency to use instincts, experiential knowledge, and intuition to solve problems, where an analytic style is a tendency to apply formal logic, methods of inquiry and theory to confront problems. Within a large research sample, factor analytic techniques define finer distinctions among these styles. In particular, we find distinctions within the analytical style, such that certain measures of analytic style (REI; Norris, Pacini, & Epstein, 1998) capture variance related to tendencies to express a deep interest in complex problem solving and openness to new information. In contrast, other measures (CSI; Allinson et al., 1996) capture variance related to tendencies to solve problems that are driven by a need for closure and conscientiousness. Subsequent correlation analysis suggests that the latter tendency covaries with susceptibility to commit errors in logical reasoning and poor performance on socio-economic forecasts elicited through the iSPADE system. Future work will clarify the relationship between cognitive styles and errors in reasoning and forecasting behavior through multi-level modeling techniques.
The Effects of Pointing out Failures of Inattentional Blindness on Performance and Situation Awareness
Authors: Dattel Andrew R. , Vogt Jason E. , Sheehan Chelsea C. , Madjic Kristen , Stefonetti Matthew C. , Miller Marissa C. , Dever Daniel. P. , Brodsky Jesse , Bradley Sierra , Fratzola Jessica K.
Published: October 2012

Eighty-two participants were categorized into one of three groups: participants with inattentional blindness (IB), participants without IB, and participants with IB, but were told about their failure to notice a salient, although irrelevant stimulus (the Show group). The Invisible Gorilla video (Simons, 2003) was used to determine IB. The effects of pointing out IB failures were tested for subsequent tasks. Performance and situation awareness (SA) of the Show group in a subsequent task of watching driving videos was compared to the IB group and the group who did not display IB. No differences in performance were found between any of the groups. The IB group was slower to answer irrelevant questions about the driving environment than participants who did not display IB. The IB group and the Show group answered irrelevant questions slower than they answered relevant questions. However, the time to answer relevant SA questions and accuracy of answering SA questions about the driving environment did not differ between the three groups. Thus, it appears that pointing out failures of an irrelevant stimulus has no effect for improving performance or SA of relevant information in subsequent tasks. Participants were further categorized as high working memory or low working memory (WM). IB participants with low WM were slower answering SA questions than IB participants with high WM.
Are there Differences in Force Exposures and Typing Productivity between Touchscreen and Conventional Keyboard?
Authors: Kim Jeong Ho , Aulck Lovenoor , Bartha Michael C , Harper Christy A , Johnson Peter W
Published: October 2012

As the use of tablets is becoming increasingly prevalent, it is important to understand how using a touchscreen (virtual) keyboard affects typing forces, productivity and comfort. Thus, the objective of this study was to investigate whether there were differences in typing forces, typing productivity and users’ discomfort between virtual and conventional keyboards. A total of 19 subjects (10 males and 9 females) typed for 10 minutes on a virtual keyboard and two conventional keyboards. The results showed that virtual keyboard use resulted in lower typing forces (p < 0.0001), lower typing performance (p < 0.0001), and higher subjective discomfort at the hand/wrist and the neck/shoulder (p < 0.0001). The results indicate that using a virtual keyboard may not cause any detrimental effect on physical exposures, but may increase musculoskeletal discomfort on the upper extremities and neck/shoulder regions; therefore, appropriate interventions should be considered for the prolonged use of a virtual keyboard.
Holding a Multi-touch Tablet with One Hand: 3D Modeling and Visualization of Hand and Wrist Postures
Authors: Feathers David J. , Zhang Han
Published: October 2012

Multi-touch tablets are increasingly being used in highly mobile work environments such as sales support, medical charting, parts tracking, and field-based work requiring real-time data. Menu options, checklists, and data entry require precise gesture-based movements. The role of stabilizing the 2D gesturing surface while performing gesture input tasks, such as rotating an on-screen image, is undertaken by the non-gesturing hand, wrist, and forearm. This research investigates stabilizing postures of the non-gesturing hand while gesture input commands are being performed. Eleven healthy volunteers performed a series of one-handed gestures on a tablet device while in an erect, unsupported seated posture. Hand coupling postures and stabilizing motions of the hand and wrist in radial and ulnar deviation, flexion and extension, and pronation and supination, are modeled in three-dimensional space. Results offer preliminary data for hand coupling positions and resulting wrist and forearm postures for multi-touch tablet computer use. Keywords: hand and wrist stabilization modeling, multi-touch, postural analysis.
Indirect Touch Pointing with Desktop Computing: Effects of Trackpad Size and Input mapping on Performance, Posture, Discomfort, and Preference
Authors: Camilleri M. , Chu B. , Ramesh A. , Odell D. , Rempel D.
Published: October 2012

Multi-touch trackpads have the advantage over traditional pointing devices (mice) in being able to recognize and act on finger gestures, such as pinching, rotating, and swiping. The primary objective of this study was to quantify the effects of desktop-trackpad size and input mapping on performance, posture and discomfort. Three trackpad sizes (112X63 mm, 178X100 mm, 230 X130 mm) and two types of input mapping, the traditional relative mapping with ‘cursor acceleration’ and absolute mapping, were tested. Subjects performed a series of target acquisition tasks (drag and select) while the dependent variables were recorded. Results suggest that peripheral indirect-touch pointing devices with a width between 112 and 178 mm and a depth between 63 and 100 mm may provide an appropriate balance between cost, footprint, performance, and comfort.
The effects of psychosocial factors on trapezius muscle activity levels during computer use
Authors: Garza Jennifer L. Bruno , Eijckelhof Belinda H.W. , Huysmans Maaike A. , Johnson Peter W. , van Dieen Jaap H. , van der Beek Allard J. , Dennerlein Jack T.
Published: October 2012

The goal of the present study, a part of the PROOF (Predicting Occupational biomechanics among OFfice workers) study, was to determine if there was a relationship between psychosocial stress, measured by reward and over-commitment, and trapezius muscle activity while workers performed their own computer work in the field. We observed that workers reporting higher levels of over-commitment and lower reward also experienced approximately 40% higher median trapeizus muscle activity levels than workers reporting lower levels of over-commitment and lower reward (change from 3.5% MVC to 6% MVC), with no difference in muscle activity for workers reporting high reward and either low or high over-commitment. Workers reporting higher levels of over-commitment experienced more variability in trapezius muscle activity. The results of this study may be used to inform interventions targeting reduction of musculoskeletal disorders among office workers.
Underlying Factors of Musculoskeletal Disorders: What Are We Missing?
Authors: Davis Kermit G. , Marras William S. , Punnett Laura , Winkelstein Beth , Blatter Birgitte
Published: October 2012

The purpose of the panel will be to discuss briefly the current knowledge of factors relating to musculoskeletal disorders in four main areas: biomechanics, psychosocial, individual characteristics, and pain sensation. The main discussion of the panel will have panelist challenge musculoskeletal disorder researchers to focus on new directions and think beyond current paradigms.
Weibull Analyses of the Fatigue Life of Human Tissues
Authors: Gallagher Sean
Published: October 2012

It is likely that many musculoskeletal disorders (MSDs) are the result of a gradual accumulation of damage that results from a process of fatigue failure. Studies on the mechanical responses of cadaveric materials to loading provide much of our knowledge of the properties of human tissues and should be of considerable interest to the ergonomist. The purpose of the present investigation was to perform Weibull analyses on data provided in fatigue failure studies of human extensor digitorum longus (EDL) and human lumbar motion segments to evaluate the reliability and fatigue life when these materials are loaded at various levels of their ultimate strength.
Changes in the range of lumbar flexion during cyclic stooping
Authors: Zhu Xinhui , Shin Gwanseob
Published: October 2012

Previously, responses to stooping or static upper body flexion have been evaluated by quantifying the changes in the range of lumbar flexion after a bout of stooping with restricted and controlled posture conditions. The current study was aimed to confirm the same with unrestricted posture conditions that resembled work-related postures. Twenty two subjects performed stooping work tasks for 6 minutes with intermediate short breaks, followed by a 6-min upright standing recovery period. Time-dependent changes in the range of lumbar flexion were evaluated by measuring peak lumbar flexion angle in full flexion trials and stooping postures before, during and after the stooping period. Results found a significant increase (p<0.05) in the peak lumbar flexion angle after stooping, and the increased range of lumbar flexion did not return to its pre-stooping level after the recovery period. Short breaks during stooping moderated the increase in the flexion range, resulting in a smaller increase in the flexion range compared to what static and controlled full flexion postures have produced in previous research.
Assessment of neck and shoulder muscle fatigue using discrete wavelet transforms of surface electromyography
Authors: Chowdhury Suman Kanti , Nimbarte Ashish D. , Jaridi Majid , Creese Robert C.
Published: October 2012

Objective assessment of neuromuscular fatigue is important for the early detection and prevention of risks of work-related musculoskeletal disorders (MSDs). Although, in recent years, a number of researchers have used discrete wavelet transforms (DWT) of surface electromyography (SEMG) to evaluate muscle fatigue, its application to neck and shoulder muscle fatigue assessment is not well established. Therefore, the purpose of this study was to establish DWT analysis as a suitable method to conduct quantitative assessment of neck and shoulder muscle fatigue caused by dynamic exertions. Six human participants performed 40 minutes of fatiguing repetitive arm and neck exertions. SEMG data from the right upper trapezius and left sternocleidomastoid muscles were recorded. Six most commonly used orthogonal wavelet functions were used to conduct DWT analysis. With the development of fatigue for most of the wavelet functions a significant increase in the power in the lower frequency bands of 12-23Hz and 23-46Hz was observed. Bior 3.1 wavelet showed the highest power, statistically consistent and meaningful power trend and the highest overall power contrast compared to the remaining five wavelets tested in this study.
Application of Near-infrared Spectroscopy in Ergonomics and Human Factors: A Discussion Panel
Authors: Maikala Rammohan V. , Mehta Ranjana K. , Ferguson Sue A. , Parasuraman R , Redfern Mark S. , Chambers April J.
Published: October 2012

This panel presents near-infrared spectroscopy (NIRS) theory and its principles, and applicability of NIRS on a variety of muscle and cerebral regions during activities that demand considerable physical and mental effort. Five presentations will cover: (1) theoretical basis of NIRS; (2) NIRS-derived hemodynamic measurements in shoulder muscles during repetitive tasks; (3) development of NIRS for use in evaluating long term standing fatigue; (4) monitoring training-related changes in prefrontal cortex activation with functional NIRS; and (5) simultaneous evaluation of physical and mental work.
Symptoms of Musculoskeletal Disorders among Tattoo Artists
Authors: Grieshaber D. Christian , Marshall Matthew M. , Fuller Thomas J.
Published: October 2012

Despite the widespread popularity of tattoos in the U.S. and worldwide, little consideration has been given to the occupational risk factors that tattoo artists face. Tattoo artists are exposed to many of the same risk factors faced by occupations such as dentistry and cosmetology, including prolonged static work postures and sustained gripping of hand held tools. However, no research has evaluated the extent to which the tattooing profession is adversely affected by its occupational demands. Utilizing a survey of tattoo artists, this research sought to benchmark the prevalence of symptoms commonly associated with the development of musculoskeletal disorders. The survey results revealed that tattoo artists experience high levels of discomfort in the lower back, neck, shoulders, and upper extremities and that these levels significantly exceed discomfort reported in professions that expose workers to similar ergonomic risk factors.
Valve Operation: Evaluation of Handwheel Actuation Techniques in Terms of Muscle Loading, Perceived Comfort, and Efficiency
Authors: Aghazadeh Fereydoun , Al-Qaisi Saif , Ikuma Laura , Hutchinson Francis
Published: October 2012

The purpose of this study was to introduce an innovative design of a valve wrench and compare it to conventional tools/methods of handwheel actuation. Four methods of handwheel actuation were evaluated, including using bare hands, regular wrench-restricted (assumes the presence of obstructions), regular wrench-unrestricted (assumes no obstructions), and modified wrench. These methods were tested on a medium-sized gate valve at two torque settings (25 Nm and 50 Nm). The methods were compared to each other, in terms of efficiency (speed), subjective ratings of perceived exertion (Borg ratings), and electromyography (EMG) activity of the left bicep and right medial deltoid. The least efficient technique at both torques was the regular wrench-restricted, and the most efficient technique was the modified wrench. At 25 Nm, the modified wrench was optimal, in that it was the most efficient and had moderately low EMG activity and Borg ratings. At 50 Nm, the regular wrench-unrestricted seemed to be the best method, having the lowest EMG activity and Borg ratings. In contrast, the bare hands technique had the highest EMG activity.
Assessment of Upper Extremity Postures in Novice and Expert during Simulated Carpentry Tasks
Authors: Ahmed Shaheen , Babski-Reeves Kari
Published: October 2012

Research has shown differences in working postures between experts and novices for lifting tasks, though there is limited research on upper extremity postural differences between experts and novices. This study quantified upper extremity postural differences between novices and experts while completing two simulated finished carpentry tasks: deck building and picket installation. A 16 camera, motion capture system was used to track upper extremity posture for 21 expert and 21 novice participants while performing 15 minute laboratory task simulations. A biomechanical model, built in AnyBody Modeling System, was used to extract seven different joint postures for wrist, elbow, and shoulder. In general, experts assumed more neutral postures, thereby reducing injury risk associated with non-neutral postures, though task, as expected, dictated the working posture assumed. The picket installation task imposed higher levels of non-neutral wrist and elbow postures; while the deck building imposed higher levels of non-neutral shoulder postures.
Can the Revised NIOSH Lifting Equation Predict Low Back Pain Incidence in a ‘90-day-pain-free-cohort’?
Authors: Boda Sruthi , Garg Arun , Campbell-Kyureghyan Naira
Published: October 2012

LBP is a major public health concern with enormous human and economic burden. The validity of the Revised NIOSH Lifting Equation (RNLE), a widely used job assessment tool, has not been studied previously in individuals with past LBP. The primary aim of this research was to study the relationship between RNLE measures and incident LBP episode risk after a 90-day pain free period using a prospective study design. One hundred and thirty industrial workers were identified as eligible to become an incident case for LBP. Univariate relationships between RNLE measures and incidence of LBP episode were studied using the Cox proportional hazards model. Significant associations between RNLE measures and incident LBP risk were found. It is concluded that the RNLE is predictive of incident LBP episode risk in individuals with past pain.
Association between Trunk Flexion and Physical Activity in Patient Care Unit Workers
Authors: Arias Oscar E. , Umukoro Peter E. , Stofell Sonja , Dennerlein Jack T. , Sorensen Glorian
Published: October 2012

The purpose of this pilot study was to characterize the direct measure of physical activity levels and the trunk posture (as a proxy for physical load) among a convenience sample of 49 Patient Care Unit workers (nurses and patient care assistants) for a single work shift. We tested the hypotheses that Patient Care Unit (PCU) worker’s increased trunk posture is associated with their direct measure of physical activity levels during one work-shift. To assess the physical activity and physical load component all participants wore an accelerometer and an inclinometer respectively. A correlation analysis was performed to assess the association between parameters of physical activity (minutes in sedentary activity, minutes in lifestyle activity, minutes in light activity and minutes in moderate activity) with parameters of physical load (number of forward trunk bends to 20° per shift, number of forward trunk bends to 45° per shift). Workers were recruited from two hospitals in Boston, Massachusetts. Eleven participants spent 86% of the time at work with a trunk flexion lower than 15°, they were considered at low exposure for back disorders. Seven PCU workers spent 33% of their work time with a trunk flexion higher than 20°, they were considered at high exposure. Twenty-one workers were classified at a medium exposure for back disorders. A high correlation was found between number of forward trunk bending to 20° per shift (spearman’s correlation: 0.56, p<0.001) with minutes in lifestyle activity. In addition, a high correlation was found among number of forward trunk bending to 45° per shift with minutes in lifestyle activity and minutes in light activity (spearman’s correlation: 0.41, p=0.005 and 0.37, p=0.01 respectively). These results suggest that physical load at work during a single shift does not contribute to meet moderate or vigorous activity levels which are the activity levels that have substantial health benefits. Further studies with a bigger sample size would be recommended to assess the association between physical loads and physical activities for more than one shift to corroborate our findings.
Biomechanical Trade-Offs in Manual Material Handling: Some Tasks Reduce Lumbar Loading But Increase Thoracic Loading
Authors: Lee Patrick J. , Lee Ellen L. , Hayes Wilson C.
Published: October 2012

Job design that is protective of the lumbar spine may inadvertently increase stresses on the thoracic spine, potentially leading to thoracic injury. In this study, we determined the ratio of thoracic to lumbar loading during various tasks, including stoop and squat lifts. Loading on the thoracic spine was calculated based on previously reported thoracic intradiscal pressures and cross-sectional areas, and compared to loading on the lumbar spine calculated using the same methodology. Results demonstrated that the ratio of thoracic and lumbar loading is not uniform and varies with the posture used during manual material handling tasks. Specifically, the loading of the thoracic spine increased during squat lifts, as compared to stoop lifts, whereas the loading on the lumbar spine decreased during squat lifts. This study adds to the body of knowledge that there are trade-offs between squat and stoops lifts and neither are without risks
An Inside Step in an Aerial Bucket Reduces Postural Instability During Ingress and Egress
Authors: Bain Bianca , Marklin Richard
Published: October 2012

The objective of this research study was to determine if an inside step in an aerial bucket reduces instability of a person entering and exiting the aerial bucket by reducing muscular exertion, which in theory can help reduce the risk of a fall. There are no publications based on laboratory or field studies regarding how the design of an aerial bucket affects postural instability and the risk of falls. Three configurations of aerial buckets (2 inside step locations and no inside step) for ingress and egress were tested to determine if the presence, and also the location, of an inside step affected three indicators of postural instability: location of person’s center of mass (CM), hand force on the bucket rim, and EMG activity of the triceps and rectus femoris (quadriceps). Sixteen electric utilities workers were tested. It was found that the presence of an inner step allowed for a lower CM of the person entering and exiting the bucket, reduced the muscle activity of the triceps and rectus femoris, and decreased hand force on the rim. Two locations of the inside step are equally beneficial. Utilities should use a removable inside step in aerial buckets that do not have a door. An inside step in an aerial bucket may benefit other industries that use buckets, such as telecommunication, tree trimming, and sign painting.
Whole Body Vibration Exposure and Seat Effective Amplitude Transmissibility of Air Suspension Seat in Different Bus Designs
Authors: Thamsuwan Ornwipa , Blood Ryan P. , Lewis Charlotte , Rynell Patrik W. , Johnson Peter W.
Published: October 2012

A number of studies have shown that whole body vibration (WBV) exposures contribute to low back pain in vehicle operators. Bus design may be an important factor in determining the WBV exposures that a driver receives. The purpose of this study was to determine whether differences exist in WBV exposures among three buses commonly used in long urban commuter routes: a high-floor coach bus, a low-floor coach bus, and a low-floor articulating bus. Each bus had the same new air-suspension installed and was driven over a standardized test route which included four road types: a smooth freeway, a rough freeway, a city street segment, and a road segment containing several speed humps. WBV exposures were evaluated per ISO 2631-1 action limits for acceptable WBV exposure levels. In this study, there were statistically significant differences among buses in WBV exposures. The high-floor coach bus had the highest fore-aft (x-axis) exposures, the low-floor articulating bus had the highest lateral (y-axis) exposures and the low-floor coach bus had the highest vertical (z-axis) exposures. With respect to ISO action limits, the z-axis WBV exposures did not exceed the 8-hour action limit (0.5 m/s2). The study also found that the air suspension seat did not perform well in the coach buses. The air suspension seat transmitted 92% of the floor measured vibration to the seat of the operator on the high-floor coach bus, 88% on the low-floor bus, and 76% on the low-floor articulating bus. Due to the low vibration attenuation performance of the air suspension seat, an evaluation of the different types of seats and seat suspensions may be merited in future research.
Macroergonomic Approach to Safety Culture/Climate: A Healthcare Facility Case Study
Authors: Loushine Todd William
Published: October 2012

A long-term care facility in the Upper Midwest was experiencing a high rate of injuries, primarily due to caregiver-patient interactions. A grounded theory case study was conducted to collect top management, supervisor, and caregiver perceptions of work system elements (centered on the caregiver job), and then compare their responses to identify discrepancies. Any discrepancies in perceptions between organizational levels are a potential point for miscommunication, poor relations, injuries, or other negative outcome. Results indicate that although management believes that injuries can be avoided by following work rules, some workers believe that getting injured is, “ just part of my job” and that overexertion and “hurrying” is expected. Organizational and social issues need to be understood before sustainable change can occur. Implications for a macroergonomic approach to safety culture assessment are discussed.
Macroergonomics in Healthcare: Principles, Progress, and Prospects
Authors: Holden Richard J. , Montague Enid , Carayon Pascale , Hoonakker Peter , Waterson Patrick , Wetterneck Tosha , Gurses Ayse , Rivera-Rodriguez A. Joy
Published: October 2012

Macroergonomics is a branch of human factors/ergonomics that can be, and indeed has been, of tremendous value to the healthcare domain. Macroergonomics offers healthcare a whole-systems orientation, a suite of methods, and numerous examples of interventions that can be successfully deployed in a variety of healthcare settings. This panel will first discuss how macroergonomic principles such as its whole-systems orientation can improve our understanding of the context of patient safety (Carayon) and the impact of health information technology (Hoonakker). Waterson (on behalf of Waterson and Eason) will present a sociotechnical analysis of a home care intervention for frail elderly patients. Wetterneck will present another multi-component intervention, this one in primary care. The panel will conclude with two examples of how macroergonomics has been used to address classic healthcare human factors issues: the implementation of electronic health records (Rivera-Rodriguez); and the classification of hazards (Gurses).
A LISREL Analysis of Work-Related Musculoskeletal Disorders in Office Workers
Authors: Chung Susan Sung Eun , Hedge Alan
Published: October 2012

A survey of 2,346 office computer users was analyzed using structural equation modeling to identify self-report individual, work characteristics, technology, and postural risk factors, determined by observation, for self-reports of work-related musculoskeletal discomfort for the neck, shoulders and arms/hands and also somatic symptoms (eyestrain, headache). The final structural equations were Somatic symptoms= 0.68*Individual factors + 0.14*Postural risk factors, with an error variance of 0.89 and explained variance of 11%; and Discomfort = 0.64*Somatic symptoms with an error variance of 0.25 and explained variance of 62%. Analysis showed that somatic symptoms mediate the effects of individual and postural risk factors on musculoskeletal discomfort symptoms.
Organizational Learning in a Large-scale Complex Health IT Project
Authors: Hundt Ann Schoofs , Carayon Pascale , Hoonakker Peter , Cartmill Randi , Herder Ruth Den , Topper Joan , Younkin Jim , Walker James
Published: October 2012

Implementing large-scale complex health IT projects poses significant challenges to organizations. This paper discusses one Office of the National Coordinator for Health IT Beacon project aimed at implementing an IT-mediated care coordination model across multiple care settings in multiple communities. We posit that using participatory ergonomic methods to collect and promptly report findings to the project management team provides significant impetus for organizational learning and increases the likelihood of success of this large-scale health IT implementation project. We describe how we involve management team members in the ongoing regular evaluation of the project through short monthly Web-based surveys and semi-annual individual interviews. The goal of this process is to promote organizational learning and impact the success of this and future complex large-scale projects.
Determination of Optimal Location of Circuit Board and Battery on 3D Glasses by Considering Nose Load and Subjective Discomfort
Authors: Chang Joonho , Jung Kihyo , Moon Seung Ki , Kim Wonmo , Freivalds Andris , Simpson Timothy W. , Baik Seon Pill
Published: October 2012

The current shutter type (SG) 3D glasses in the market are heavy (41 g) and have a poor weight balance due to a battery and a circuit board on the temples of the glasses. Therefore, it causes high pressure on the nose and discomfort for the users. This study determined the optimal location of a circuit board and a battery for SG type 3D glasses. Four 3D glasses with different weight distributions (the battery and the circuit board locations: front, middle, ear, and rear positions) were employed in the experiments. Subjective discomfort ratings (100 point scale) around the nose and the posterior edge of the ear were obtained after wearing the four 3D glasses. Also, at the same time the load on the nose was measured by using FSR (force sensing resistor) film sensors. As a result, the front position showed the highest subjective discomfort rating on the nose. Discomfort ratings on the nose were decreased significantly as the location of the battery and circuit board moved backward on the temples (p = 0.0009). On the other hand, the ear position showed the highest subjective discomfort rating on the posterior edge of the ear, and, as opposed to the nose, the subjective discomfort ratings for the posterior edge of the ear tended to increase as the battery and circuit board moved backward (p = 0.0093). The highest nose load, 0.34 N, was found on the front position, and the load on the nose was decreased significantly as the location of the battery and circuit board moved backward (p < 0.001). Also, the nose loads had a strong correlation with the discomfort ratings on the nose ( Radj2 = 99.1%), but no strong correlation was found with the subjective discomfort ratings on the posterior edge of the ear ( Radj2 = 19.6%). Consequently, the middle position was recommended as the optimal location of the battery and circuit board on the temples of the SG type 3D glasses by considering the above results.
Optimal interface location and limits of gesture proficiency in an automobile
Authors: Eisert Jesse L. , Gartenberg Daniel , Thornton Ross , Youmans Robert J.
Published: October 2012

This paper explores the optimal location of gesture based in-vehicle technology for minimizing driver distraction, as well as the specific manipulative gestures that would accompany such gesture based in-vehicle technologies. Three different vehicle locations and ten different driver gestures were evaluated during testing. Participants in the study performed each of the gestures at all three locations, and results indicated that most individuals preferred using the steering wheel location. Participants’ responses indicated that they felt most comfortable with a repertoire of about seven gestures. Our initial findings suggest that a gesture-based interface system might be most effective when placed at the three o’clock position on the steering wheel, and when thee systems operate using a maximum of seven gestures.
Adjusting Fitts’ Paradigm for Small Touch-Sensitive Input Device with Large Group of Users
Authors: Kim Inki , Jo Jang Hyeon
Published: October 2012

Fitts’ paradigm is a classic theory to describe the relationship between movement time, distance and accuracy for rapid aimed movement. Generally speaking, it describes the Speed-Accuracy Tradeoff (SAT) along task condition as well as along users. A controlled factorial experiment is conducted for small touch-sensitive input device to observe SAT relationship within task condition and large number of users. Fitts’ paradigm did not successfully model the SAT relationship, due to ambiguous definition of accuracy index and lack of variables to reflect subject bias. Fitts’ paradigm was adjusted by revising accuracy index appropriate for direct finger input, and by introducing a trajectory variable to keep track of the subject bias. It raised the model fit (R2) from 0.523 to 0.833 for a model of task condition.
Usability of e-Readers for Book Navigation Tasks
Authors: Jardina Jo R. , Chaparro Barbara S.
Published: October 2012

Even though more people are beginning to use e-Readers, electronic reading devices, little research exists on the usability of these devices for book reading. This study looks at the usability of three touch-screen e-Readers (iPad, Kindle Fire, and Nook Tablet) for basic book navigation tasks. During the study, participants ( N = 16) were asked to complete a series of tasks (e.g., bookmarking a page, highlighting text, etc.) on the three e-Readers, and rate the difficulty of each task. Task completion time and number of taps required to complete each task on each device was also recorded. Participants rated each device on their perception of workload and satisfaction. When they completed all the tasks on all the devices, participants were asked to rank each device on a series of attributes and overall preference. Results revealed no overall “winner” and no significant differences between the devices on perceived workload and satisfaction. Each device proved to have some strengths and weaknesses by task. The Nook was preferred more than the iPad and Kindle for its menu structure, and the iPad was ranked higher than the Kindle and Nook on highlighting and notes. The Kindle was preferred for tasks which required changing text size and text searching. Suggestions are offered for the improvement of future touch screen e-Readers.
Exploration of Gesture-Based Control for Tunable Solid State Lighting Applications
Authors: Spaulding Jeremy M. , Holt Jeffrey
Published: October 2012

In a shift from most traditional lighting systems found in the home or office, Solid Sate Lighting (SSL) systems base on Light-Emitting Diode (LED) technology are being created with increasing levels of control over light output, including color tunability. With increased complexity and control comes the need to improve the user experience. Tunability in solid state lighting means that nearly every aspect of a light source can be tailored to any specific application. Use of gesture-based interfaces is becoming commonplace and has enabled the gaming and mobile computing industries to create user experiences that previous methods of control simply could not provide. The purpose of this design and development activity was to explore fully tunable (RGBY) SSL system control using a free space 3D gesture control system. There were many lessons learned from this exercise from both a technical and use perspective. This research and development activity resulted in the successful development of a gesture-based tunable lighting concept and better understanding and refining this type of system.
Enabling comfortable thumb interaction in tablet computers: a Windows 8 case study
Authors: Odell Dan , Chandrasekaran Vasudha
Published: October 2012

Holding a tablet computer in two hands and interacting via the thumbs is an important and commonly observed method of tablet interaction. This paper presents a methodology for measuring and reporting thumb reach in a way that enables designers of user interfaces (UI) to design UIs that can be comfortably reached by the thumbs. The process is to identify the relevant anthropometric measure and target population, identify how people grip the device, measure reach areas for different groups and grips, and to use the data to create graphical ‘heat maps’ along with guidance that designers can use to place their interface elements into easily reachable areas of the screen. The methodology is illustrated with an example of how it was used in the development of Microsoft Windows 8.