Pub Date : 2014-01-01Epub Date: 2014-11-24DOI: 10.1080/21577323.2014.919367
Gurjeet Singh, Kurt E Beschorner
Background: Fluid contaminants cause slipping accidents by reducing shoe-floor friction. Fluid pressures in the shoe-floor interface reduce contact between the surfaces and, thus, reduce friction between the surfaces. A technological gap for measuring fluid pressures, however, has impeded improved understanding of what factors influence these pressures.
Purpose: This study aimed to introduce a technique for measuring fluid pressures under the shoe and to demonstrate the utility of the technique by quantifying the effects of tread depth and fluid viscosity on fluid pressures for two different shoes.
Methods: A fluid pressure sensor embedded in the floor surface was used to measure fluid pressures, while a robotic slip-tester traversed the shoe over the floor surface. Multiple scans were collected to develop 2D fluid pressure maps across the shoe surface. Two shoe tread types (an athletic shoe and a work shoe), two fluids (high-viscosity diluted glycerol and a low-viscosity detergent solution), and three tread depths (full tread, half tread, and no tread) were tested, while fluid pressures were measured.
Results: Untreaded shoes combined with a high-viscosity fluid resulted in high fluid pressures, while treaded shoes or low-viscosity fluids resulted in low fluid pressures. The increased fluid pressures that were observed for the untreaded shoes are consistent with tribology theory and evidence from human slipping studies.
Conclusions: The methods described here successfully measured fluid pressures and yielded results consistent with tribological theory and human slipping experiments. This approach offers significant potential in evaluating the slip-resistance of tread designs and determining wear limits for replacing shoes.
{"title":"A Method for Measuring Fluid Pressures in the Shoe-Floor-Fluid Interface: Application to Shoe Tread Evaluation.","authors":"Gurjeet Singh, Kurt E Beschorner","doi":"10.1080/21577323.2014.919367","DOIUrl":"https://doi.org/10.1080/21577323.2014.919367","url":null,"abstract":"<p><strong>Background: </strong>Fluid contaminants cause slipping accidents by reducing shoe-floor friction. Fluid pressures in the shoe-floor interface reduce contact between the surfaces and, thus, reduce friction between the surfaces. A technological gap for measuring fluid pressures, however, has impeded improved understanding of what factors influence these pressures.</p><p><strong>Purpose: </strong>This study aimed to introduce a technique for measuring fluid pressures under the shoe and to demonstrate the utility of the technique by quantifying the effects of tread depth and fluid viscosity on fluid pressures for two different shoes.</p><p><strong>Methods: </strong>A fluid pressure sensor embedded in the floor surface was used to measure fluid pressures, while a robotic slip-tester traversed the shoe over the floor surface. Multiple scans were collected to develop 2D fluid pressure maps across the shoe surface. Two shoe tread types (an athletic shoe and a work shoe), two fluids (high-viscosity diluted glycerol and a low-viscosity detergent solution), and three tread depths (full tread, half tread, and no tread) were tested, while fluid pressures were measured.</p><p><strong>Results: </strong>Untreaded shoes combined with a high-viscosity fluid resulted in high fluid pressures, while treaded shoes or low-viscosity fluids resulted in low fluid pressures. The increased fluid pressures that were observed for the untreaded shoes are consistent with tribology theory and evidence from human slipping studies.</p><p><strong>Conclusions: </strong>The methods described here successfully measured fluid pressures and yielded results consistent with tribological theory and human slipping experiments. This approach offers significant potential in evaluating the slip-resistance of tread designs and determining wear limits for replacing shoes.</p>","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":" ","pages":"53-59"},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2014.919367","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37253133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1080/21577323.2013.867186
Editorial Board: Michael J. Agnew, Virginia Tech, USA Ellen J. Bass, Drexel University, USA Ole Broberg, Technical University of Denmark (DTU) Catherine Burns, University of Waterloo, Canada Rakié Cham, University of Pittsburgh, USA Patrick G. Dempsey, NIOSH, USA Jack Dennerlein, Northeastern University, USA Donald L. Fisher, University of Massachusetts, Amherst, USA Matthias Goebel, Rhodes University, South Africa Richard J. Holden, Vanderbilt University, USA Marco J.M. Hoozemans, VU University Amsterdam, The Netherlands Peter Johnson, University of Washington, USA David B. Kaber, North Carolina State University, USA Steve Lavender, The Ohio State University, USA John D. Lee, University of Wisconsin-Madison, USA Gary A. Mirka, Iowa State University, USA W. Patrick Neumann, Ryerson University, Canada Victor L. Pacquet, University at Buffalo, USA Raja Parasuraman, George Mason University, USA Amy R. Pritchett, Georgia Institute of Technology, USA Matthew P. Reed, The University of Michigan, USA David M. Rempel, University of California, USA Michelle M. Robertson, Liberty Mutual Research Institute for Safety, USA Ling Rothrock, Penn State University, USA Tonya L. Smith-Jackson, North Carolina A&T State University, USA Jaap H. van Dieën, VU University Amsterdam, The Netherlands Patrick Waterson, Loughborough University, UK Richard P. Wells, University of Waterloo, Canada
{"title":"Editorial Board EOV","authors":"","doi":"10.1080/21577323.2013.867186","DOIUrl":"https://doi.org/10.1080/21577323.2013.867186","url":null,"abstract":"Editorial Board: Michael J. Agnew, Virginia Tech, USA Ellen J. Bass, Drexel University, USA Ole Broberg, Technical University of Denmark (DTU) Catherine Burns, University of Waterloo, Canada Rakié Cham, University of Pittsburgh, USA Patrick G. Dempsey, NIOSH, USA Jack Dennerlein, Northeastern University, USA Donald L. Fisher, University of Massachusetts, Amherst, USA Matthias Goebel, Rhodes University, South Africa Richard J. Holden, Vanderbilt University, USA Marco J.M. Hoozemans, VU University Amsterdam, The Netherlands Peter Johnson, University of Washington, USA David B. Kaber, North Carolina State University, USA Steve Lavender, The Ohio State University, USA John D. Lee, University of Wisconsin-Madison, USA Gary A. Mirka, Iowa State University, USA W. Patrick Neumann, Ryerson University, Canada Victor L. Pacquet, University at Buffalo, USA Raja Parasuraman, George Mason University, USA Amy R. Pritchett, Georgia Institute of Technology, USA Matthew P. Reed, The University of Michigan, USA David M. Rempel, University of California, USA Michelle M. Robertson, Liberty Mutual Research Institute for Safety, USA Ling Rothrock, Penn State University, USA Tonya L. Smith-Jackson, North Carolina A&T State University, USA Jaap H. van Dieën, VU University Amsterdam, The Netherlands Patrick Waterson, Loughborough University, UK Richard P. Wells, University of Waterloo, Canada","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":"1 1","pages":"ebi - ebi"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2013.867186","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60123268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1080/21577323.2013.852145
Ya Li, K. Itoh
OCCUPATIONAL APPLICATIONS This study sought to identify factors contributing to preventable road traffic crashes, based on analyses of crash records collected from 18 trucking companies in Japan. Road crashes in the trucking industry were found to be associated with the following factors: penalty points of the driver's license, emotional stability, safety attitudes, delivery area or range, driver workload, and driving experience. In addition to well-known causal factors for driver errors in road transport, these results suggest that managers in a trucking firm should provide drivers with safety-oriented work schedules to control stress and workload. Examples include more frequent breaks (for a shorter duration), particularly for medium- or long-distance drivers, controlling annual driving distance, and training not only for technical skills but also for enhanced safety attitudes and behaviors. TECHNICAL ABSTRACT Background: Occupational traffic safety is recognized as one of the most crucial social issues to address in many countries. Yet, causal factors for road crashes involving occupational drivers have not been fully investigated. Purpose: This study sought to identify important factors contributing to safety outcomes of occupational truck drivers in Japan. Methods: A total of 1292 drivers’ road crash and work-related records were collected from 18 trucking companies in Japan. Each record specified individual and task-related attributes and history of road crashes from 2004 to 2006. As individual attributes, each record included age, gender, experience, employment condition, supervisor assessment of fuel-efficient driving, penalty points on driver's license, scores of five personality and attitude factors, and four sensorimotor functions measured by a driver aptitude test. Examples of task-related attributes were vehicle type, delivery, and annual working days. Chi-square tests were used to examine differences between “crash-free” and “crash-involved” drivers for potential contributing factors. Results: Several driver factors contributing to safety performance were identified. For instance, years of occupational driving experience were positively associated with higher levels of traffic safety. Drivers with fewer driver's license penalty points were less likely to have been involved in a road crash. Results also suggested that drivers’ emotional stability and positive safety attitudes are associated with lower involvement in road crashes. In addition to these individual attributes, some task-related factors were identified that may influence the likelihood of crash involvement (e.g., delivery range and annual driving distance). Conclusions: Several driver factors, such as fewer driver's license penalty points, high emotional stability, positive safety attitudes, and reasonable workload, were associated with mitigation of crash risk. This suggests that occupational truck drivers should be provided safety-oriented work schedules and conditions
{"title":"Factors Contributing to Driving Safety in the Trucking Industry","authors":"Ya Li, K. Itoh","doi":"10.1080/21577323.2013.852145","DOIUrl":"https://doi.org/10.1080/21577323.2013.852145","url":null,"abstract":"OCCUPATIONAL APPLICATIONS This study sought to identify factors contributing to preventable road traffic crashes, based on analyses of crash records collected from 18 trucking companies in Japan. Road crashes in the trucking industry were found to be associated with the following factors: penalty points of the driver's license, emotional stability, safety attitudes, delivery area or range, driver workload, and driving experience. In addition to well-known causal factors for driver errors in road transport, these results suggest that managers in a trucking firm should provide drivers with safety-oriented work schedules to control stress and workload. Examples include more frequent breaks (for a shorter duration), particularly for medium- or long-distance drivers, controlling annual driving distance, and training not only for technical skills but also for enhanced safety attitudes and behaviors. TECHNICAL ABSTRACT Background: Occupational traffic safety is recognized as one of the most crucial social issues to address in many countries. Yet, causal factors for road crashes involving occupational drivers have not been fully investigated. Purpose: This study sought to identify important factors contributing to safety outcomes of occupational truck drivers in Japan. Methods: A total of 1292 drivers’ road crash and work-related records were collected from 18 trucking companies in Japan. Each record specified individual and task-related attributes and history of road crashes from 2004 to 2006. As individual attributes, each record included age, gender, experience, employment condition, supervisor assessment of fuel-efficient driving, penalty points on driver's license, scores of five personality and attitude factors, and four sensorimotor functions measured by a driver aptitude test. Examples of task-related attributes were vehicle type, delivery, and annual working days. Chi-square tests were used to examine differences between “crash-free” and “crash-involved” drivers for potential contributing factors. Results: Several driver factors contributing to safety performance were identified. For instance, years of occupational driving experience were positively associated with higher levels of traffic safety. Drivers with fewer driver's license penalty points were less likely to have been involved in a road crash. Results also suggested that drivers’ emotional stability and positive safety attitudes are associated with lower involvement in road crashes. In addition to these individual attributes, some task-related factors were identified that may influence the likelihood of crash involvement (e.g., delivery range and annual driving distance). Conclusions: Several driver factors, such as fewer driver's license penalty points, high emotional stability, positive safety attitudes, and reasonable workload, were associated with mitigation of crash risk. This suggests that occupational truck drivers should be provided safety-oriented work schedules and conditions ","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":"1 1","pages":"246 - 257"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2013.852145","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60123080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1080/21577323.2013.844209
L. Steiner, R. Burgess-Limerick
OCCUPATIONAL APPLICATIONS Shape-coding and length-coding of control levers may have limited benefits for the prevention of selection errors during operation of roof-bolting machines and other industrial equipment. Any benefits of arbitrary shape-coding or length-coding for reducing selection errors are likely to be restricted to situations in which the arrangement of controls in relation to the participant is subsequently altered in some way, such as the operator moving from one machine to another with a different control layout. If shape-coding is employed, measures should be taken to ensure that the relationship between shape and function remains consistent across similar equipment and that the relationship between shape and function cannot be altered in error during maintenance. TECHNICAL ABSTRACT Rationale: Underground coal mining is one of the most hazardous industrial environments, and roof-bolting machine operators are the most at-risk occupation in underground coal mining. Many examples of industrial equipment, including bolting machines used in underground coal mines, are operated via a bank of levers that control different machine functions and movements. Errors in the use of these controls are a cause of serious injuries. Purpose: A recent design guideline for underground bolting equipment has specified the use of arbitrary shape-coding for principal equipment functions with the aim of reducing injuries caused by operators inadvertently operating the wrong lever (a selection error). Three experiments were conducted to provide further insight to the use of control-coding. Methods: Sixty-four individuals participated in three experiments. Each participant operated a physical simulation of a single-boom roof-bolter machine via five levers in either shape-coded, length-coded, or identical handle conditions. In two experiments, the location of the controls was changed half-way through the experiment. Selection error rate data were collected. Results: When operators are not under time pressure, their attention is not divided, and they are able to view the controls they are manipulating, any benefits of arbitrary shape-coding or length-coding for reducing selection errors are likely to be restricted to situations in which the arrangement of controls in relation to the participant is subsequently altered. Conclusions: If shape-coding is employed, measures should be taken to ensure that the relationship between shape and function remains consistent and that maintenance errors, such as reversing handle shapes, are prevented.
{"title":"Shape-Coding and Length-Coding as a Measure to Reduce the Probability of Selection Errors During the Control of Industrial Equipment","authors":"L. Steiner, R. Burgess-Limerick","doi":"10.1080/21577323.2013.844209","DOIUrl":"https://doi.org/10.1080/21577323.2013.844209","url":null,"abstract":"OCCUPATIONAL APPLICATIONS Shape-coding and length-coding of control levers may have limited benefits for the prevention of selection errors during operation of roof-bolting machines and other industrial equipment. Any benefits of arbitrary shape-coding or length-coding for reducing selection errors are likely to be restricted to situations in which the arrangement of controls in relation to the participant is subsequently altered in some way, such as the operator moving from one machine to another with a different control layout. If shape-coding is employed, measures should be taken to ensure that the relationship between shape and function remains consistent across similar equipment and that the relationship between shape and function cannot be altered in error during maintenance. TECHNICAL ABSTRACT Rationale: Underground coal mining is one of the most hazardous industrial environments, and roof-bolting machine operators are the most at-risk occupation in underground coal mining. Many examples of industrial equipment, including bolting machines used in underground coal mines, are operated via a bank of levers that control different machine functions and movements. Errors in the use of these controls are a cause of serious injuries. Purpose: A recent design guideline for underground bolting equipment has specified the use of arbitrary shape-coding for principal equipment functions with the aim of reducing injuries caused by operators inadvertently operating the wrong lever (a selection error). Three experiments were conducted to provide further insight to the use of control-coding. Methods: Sixty-four individuals participated in three experiments. Each participant operated a physical simulation of a single-boom roof-bolter machine via five levers in either shape-coded, length-coded, or identical handle conditions. In two experiments, the location of the controls was changed half-way through the experiment. Selection error rate data were collected. Results: When operators are not under time pressure, their attention is not divided, and they are able to view the controls they are manipulating, any benefits of arbitrary shape-coding or length-coding for reducing selection errors are likely to be restricted to situations in which the arrangement of controls in relation to the participant is subsequently altered. Conclusions: If shape-coding is employed, measures should be taken to ensure that the relationship between shape and function remains consistent and that maintenance errors, such as reversing handle shapes, are prevented.","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":"1 1","pages":"224 - 234"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2013.844209","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60123234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1080/21577323.2013.847873
A. Chourasia, D. Wiegmann, Karen B. Chen, M. Sesto
OCCUPATIONAL APPLICATIONS Sitting in a parallel orientation in front of a touch screen (requiring twisting of the torso) was found to cause a decrement in touchscreen performance (36%–48%). However, the adverse effect of sitting orientation on performance could be ameliorated by interface design, most notably by using button sizes greater than 20×20 mm. Larger button sizes also benefit individuals with upper extremity motor control disabilities, and this information could be used to incorporate universal design in touchscreen interfaces. Larger button sizes also help in reducing the force-time integral during button activation. Touchscreens are widely used in occupational settings, such as retail, restaurants, and health care. The touchscreen performance findings from this study are applicable to touchscreen interface design for users with and without upper extremity motor control disabilities, and the touch characteristics findings are useful for ergonomists quantifying forces involved in touchscreen operation. TECHNICAL ABSTRACT Background: Touchscreens can be used in stand-alone kiosks, embedded in larger structures, such as walls, or arranged in multi-display configurations (e.g., a control station). As a result, users may not always be positioned in front of the screen and may instead operate it in a variety of orientations. Previous touchscreen research has not considered the effect of user sitting orientation on touchscreen performance, such as in terms of the number of errors (incorrect button activation), misses (touch that does not result in button activation), task completion time, and touch characteristics (e.g., force, dwell time [the time the button was pressed], and force-time integral). Purpose: This study evaluates the effect of sitting orientation on performance and touch characteristics during a digit entry task among individuals with and without motor control disabilities, including wheelchair users and non-users. Methods: Participants with (n = 21) and without (n = 21) upper extremity motor control disabilities (+MCD and −MCD, respectively) completed a four-digit entry task on a touchscreen in both front and parallel orientations to the touchscreen. Button sizes of 10×10 to 30×30 mm (5-mm increments) and two button gaps (3 or 5 mm) were used. Results: Accuracy was adversely affected, with errors (36%) and misses (48%) greater in the parallel orientation. Dwell time (12%) and force-time integral (21%) were also greater in the parallel orientation than in the front orientation. Larger button sizes (≥20 mm) lowered misses, errors, force-time integrals, and dwell times for both orientations. The +MCD group had a greater percentage of trials with misses (150%) and longer dwell times (66%) than the −MCD group, but in general, similar trends in performance and touch characteristics were observed for both groups across button sizes, button gaps, and sitting orientation. Conclusions: Decrements in touchscreen performance occurred in t
{"title":"Effect of Sitting Orientation on Touchscreen Performance, Touch Characteristics, User Preference, and Workload","authors":"A. Chourasia, D. Wiegmann, Karen B. Chen, M. Sesto","doi":"10.1080/21577323.2013.847873","DOIUrl":"https://doi.org/10.1080/21577323.2013.847873","url":null,"abstract":"OCCUPATIONAL APPLICATIONS Sitting in a parallel orientation in front of a touch screen (requiring twisting of the torso) was found to cause a decrement in touchscreen performance (36%–48%). However, the adverse effect of sitting orientation on performance could be ameliorated by interface design, most notably by using button sizes greater than 20×20 mm. Larger button sizes also benefit individuals with upper extremity motor control disabilities, and this information could be used to incorporate universal design in touchscreen interfaces. Larger button sizes also help in reducing the force-time integral during button activation. Touchscreens are widely used in occupational settings, such as retail, restaurants, and health care. The touchscreen performance findings from this study are applicable to touchscreen interface design for users with and without upper extremity motor control disabilities, and the touch characteristics findings are useful for ergonomists quantifying forces involved in touchscreen operation. TECHNICAL ABSTRACT Background: Touchscreens can be used in stand-alone kiosks, embedded in larger structures, such as walls, or arranged in multi-display configurations (e.g., a control station). As a result, users may not always be positioned in front of the screen and may instead operate it in a variety of orientations. Previous touchscreen research has not considered the effect of user sitting orientation on touchscreen performance, such as in terms of the number of errors (incorrect button activation), misses (touch that does not result in button activation), task completion time, and touch characteristics (e.g., force, dwell time [the time the button was pressed], and force-time integral). Purpose: This study evaluates the effect of sitting orientation on performance and touch characteristics during a digit entry task among individuals with and without motor control disabilities, including wheelchair users and non-users. Methods: Participants with (n = 21) and without (n = 21) upper extremity motor control disabilities (+MCD and −MCD, respectively) completed a four-digit entry task on a touchscreen in both front and parallel orientations to the touchscreen. Button sizes of 10×10 to 30×30 mm (5-mm increments) and two button gaps (3 or 5 mm) were used. Results: Accuracy was adversely affected, with errors (36%) and misses (48%) greater in the parallel orientation. Dwell time (12%) and force-time integral (21%) were also greater in the parallel orientation than in the front orientation. Larger button sizes (≥20 mm) lowered misses, errors, force-time integrals, and dwell times for both orientations. The +MCD group had a greater percentage of trials with misses (150%) and longer dwell times (66%) than the −MCD group, but in general, similar trends in performance and touch characteristics were observed for both groups across button sizes, button gaps, and sitting orientation. Conclusions: Decrements in touchscreen performance occurred in t","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":"1 1","pages":"235 - 245"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2013.847873","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60123388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-09-12DOI: 10.1080/21577323.2013.840342
A. Nimbarte, J. Sivak-Callcott, Majed M. Zreiqat, Marsha Chapman
OCCUPATIONAL APPLICATIONS Surgical tasks performed using loupes and headlamps were examined to identify exposures to physical risk factors for work-related musculoskeletal disorders in the neck among microsurgeons. Surgeons who use loupes and headlamps were found to spend extensive time periods working in non-neutral head–neck postures. These postures, and the use of loupes and headlamps, were found to be associated with an increased loading of the cervical spine, which might cumulatively contribute to occupational neck musculoskeletal disorders. To develop effective control strategies, future studies should focus on the impact of design features of loupes (e.g., mount angles, weight, and shape) on head–neck postures during surgical tasks. TECHNICAL ABSTRACT Background: Work-related musculoskeletal disorders in the neck are common among microsurgeons who operate with loupes and headlamps. Published surveys indicate that microsurgeons across many subspecialties believe that loupes contribute to neck musculoskeletal disorders. However, objective data on head–neck posture and cervical loading during surgical tasks performed using loupes and headlamps are currently lacking. Purpose: This study will assess exposures to physical risk factors for neck musculoskeletal disorders during surgical tasks performed using loupes and headlamp. Methods: A field study was performed in operating rooms to measure the head–neck postures commonly used by three ophthalmic plastic surgeons; a subset of microsurgeons. Posture data were used as input to a biomechanical model to estimate cervical spine loading. Results: During nearly 85% of the time spent operating, surgeons adopted asymmetrical head–neck postures characterized by either bending or rotation of >15°, coupled with flexion of >15°. Postures consisting of flexion ≥45°, 15°–30° bending, and 15°–45° rotation produced significantly higher biomechanical loading of the cervical spine compared to near-neutral postures (i.e., flexion, bending and rotation between 0° and 15°). This loading was further exaggerated by the weight of loupes and headlamp. Conclusions: Non-neutral head–neck postures demanded by the dexterous operating tasks performed using loupes and headlamps could be important biomechanical risk factors for cervical musculoskeletal disorders among microsurgeons.
{"title":"Neck Postures and Cervical Spine Loading Among Microsurgeons Operating with Loupes and Headlamp","authors":"A. Nimbarte, J. Sivak-Callcott, Majed M. Zreiqat, Marsha Chapman","doi":"10.1080/21577323.2013.840342","DOIUrl":"https://doi.org/10.1080/21577323.2013.840342","url":null,"abstract":"OCCUPATIONAL APPLICATIONS Surgical tasks performed using loupes and headlamps were examined to identify exposures to physical risk factors for work-related musculoskeletal disorders in the neck among microsurgeons. Surgeons who use loupes and headlamps were found to spend extensive time periods working in non-neutral head–neck postures. These postures, and the use of loupes and headlamps, were found to be associated with an increased loading of the cervical spine, which might cumulatively contribute to occupational neck musculoskeletal disorders. To develop effective control strategies, future studies should focus on the impact of design features of loupes (e.g., mount angles, weight, and shape) on head–neck postures during surgical tasks. TECHNICAL ABSTRACT Background: Work-related musculoskeletal disorders in the neck are common among microsurgeons who operate with loupes and headlamps. Published surveys indicate that microsurgeons across many subspecialties believe that loupes contribute to neck musculoskeletal disorders. However, objective data on head–neck posture and cervical loading during surgical tasks performed using loupes and headlamps are currently lacking. Purpose: This study will assess exposures to physical risk factors for neck musculoskeletal disorders during surgical tasks performed using loupes and headlamp. Methods: A field study was performed in operating rooms to measure the head–neck postures commonly used by three ophthalmic plastic surgeons; a subset of microsurgeons. Posture data were used as input to a biomechanical model to estimate cervical spine loading. Results: During nearly 85% of the time spent operating, surgeons adopted asymmetrical head–neck postures characterized by either bending or rotation of >15°, coupled with flexion of >15°. Postures consisting of flexion ≥45°, 15°–30° bending, and 15°–45° rotation produced significantly higher biomechanical loading of the cervical spine compared to near-neutral postures (i.e., flexion, bending and rotation between 0° and 15°). This loading was further exaggerated by the weight of loupes and headlamp. Conclusions: Non-neutral head–neck postures demanded by the dexterous operating tasks performed using loupes and headlamps could be important biomechanical risk factors for cervical musculoskeletal disorders among microsurgeons.","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":"1 1","pages":"215 - 223"},"PeriodicalIF":0.0,"publicationDate":"2013-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2013.840342","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60122959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-09-09DOI: 10.1080/21577323.2013.838195
W. Tharion, M. Buller, Adam W. Potter, A. J. Karis, Victoria Goetz, R. Hoyt
OCCUPATIONAL APPLICATIONS A physiological status monitoring system was evaluated for use by soldiers in the field. Two different designs were evaluated, with the design based on previous human factors evaluations proven to be more comfortable and acceptable for use. This study demonstrated that the advanced design of the EQ-02 physiological status monitoring system met dismounted soldier needs. Furthermore, this study validated the use of a usability evaluation in the successful design/advancement of a physiological status monitoring system. TECHNICAL ABSTRACT Background: Previous research has shown that the form factor of a physiological status monitoring system, the Equivital™ EQ-01 (Hidalgo Ltd., Cambridge, UK) had problems associated with comfort and usability of the system for soldiers. Previous data gathered was used to guide improvements in the physiological status monitoring system. Purpose: Assess whether the previous feedback from usability evaluations helped guide improvements in comfort, acceptability, and usability of a physiological status monitoring system for dismounted soldiers. Improvements to the EQ-01 system were incorporated into the next-generation EQ-02 (Hidalgo Ltd., Cambridge, UK) system. Methods: Thirty-nine infantry dismounted soldiers were randomly assigned to wear either an EQ-01 or EQ-02 system while performing standard military field training. They filled out a survey on fit, comfort, irritation to the body, impact on military performance, and acceptability. They then wore the other system and filled out the same survey. Results: The Equivital™ EQ-02 system was superior in terms of fit (51% better in overall fit), ease of donning (10% easier), comfort (45% more comfortable), impact on military performance (45% less impact), impact on the body (17% less impact), and acceptability (32% more acceptable). All these measures are subjective self-report ratings. Conclusions: A human factors engineering approach provided an effective means of guiding improvements and the production of a physiological status monitoring system that dismounted soldiers were more likely to accept and wear.
{"title":"Acceptability and Usability of an Ambulatory Health Monitoring System for Use by Military Personnel","authors":"W. Tharion, M. Buller, Adam W. Potter, A. J. Karis, Victoria Goetz, R. Hoyt","doi":"10.1080/21577323.2013.838195","DOIUrl":"https://doi.org/10.1080/21577323.2013.838195","url":null,"abstract":"OCCUPATIONAL APPLICATIONS A physiological status monitoring system was evaluated for use by soldiers in the field. Two different designs were evaluated, with the design based on previous human factors evaluations proven to be more comfortable and acceptable for use. This study demonstrated that the advanced design of the EQ-02 physiological status monitoring system met dismounted soldier needs. Furthermore, this study validated the use of a usability evaluation in the successful design/advancement of a physiological status monitoring system. TECHNICAL ABSTRACT Background: Previous research has shown that the form factor of a physiological status monitoring system, the Equivital™ EQ-01 (Hidalgo Ltd., Cambridge, UK) had problems associated with comfort and usability of the system for soldiers. Previous data gathered was used to guide improvements in the physiological status monitoring system. Purpose: Assess whether the previous feedback from usability evaluations helped guide improvements in comfort, acceptability, and usability of a physiological status monitoring system for dismounted soldiers. Improvements to the EQ-01 system were incorporated into the next-generation EQ-02 (Hidalgo Ltd., Cambridge, UK) system. Methods: Thirty-nine infantry dismounted soldiers were randomly assigned to wear either an EQ-01 or EQ-02 system while performing standard military field training. They filled out a survey on fit, comfort, irritation to the body, impact on military performance, and acceptability. They then wore the other system and filled out the same survey. Results: The Equivital™ EQ-02 system was superior in terms of fit (51% better in overall fit), ease of donning (10% easier), comfort (45% more comfortable), impact on military performance (45% less impact), impact on the body (17% less impact), and acceptability (32% more acceptable). All these measures are subjective self-report ratings. Conclusions: A human factors engineering approach provided an effective means of guiding improvements and the production of a physiological status monitoring system that dismounted soldiers were more likely to accept and wear.","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":"1 1","pages":"203 - 214"},"PeriodicalIF":0.0,"publicationDate":"2013-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2013.838195","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60123293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-07-01DOI: 10.1080/21577323.2013.822034
Leanna M. Horton, M. Nussbaum, M. Agnew
OCCUPATIONAL APPLICATIONS This study simulated rotating between assembly tasks at two different intensity levels performed for a total duration of 1 hour, during which rotation occurred every 15 minutes, every 30 minutes, or not at all. Under the scenario studied here, rotation reduced shoulder muscle fatigue compared to only performing a higher intensity task and increased fatigue compared to only performing a lower intensity task. Neither rotation frequency nor starting task significantly affected fatigue or performance. Based on the results, rotation frequency and starting task may not need substantial consideration when designing rotation schedules or plans. Generalizing the current results to actual occupational tasks, however, may be limited due to the inclusion of only two tasks, the constrained nature of the task, and the small sample size. TECHNICAL ABSTRACT Background: Rotating between tasks is widely used and considered to reduce the risk of work-related musculoskeletal disorders, though there is limited evidence that it is effective in doing so. Purpose: This study assessed the effects of rotation during assembly work involving the upper extremity, specifically focusing on rotation frequency and starting task, on shoulder muscle fatigue and task performance when included tasks loaded the same muscle group. Methods: Twelve participants completed six experimental sessions during which a simulated repetitive assembly task was performed for 1 hour either with or without rotation. When rotation occurred, it was between two intensity levels corresponding to two working heights. Results: As expected, rotating between the tasks reduced shoulder muscle fatigue compared to only performing the higher intensity task and increased fatigue compared to only performing the lower intensity task. Neither rotation frequency nor starting task had significant or consistent effects on fatigue or task performance. Conclusions: While varying the intensity level of tasks included in rotation schedules reduced muscle fatigue, this effect was not influenced substantially by either rotation frequency or starting task during the moderately demanding upper extremity assembly task examined here.
{"title":"Effects of Rotation Frequency and Starting Task on Localized Muscle Fatigue and Performance During Simulated Assembly Work","authors":"Leanna M. Horton, M. Nussbaum, M. Agnew","doi":"10.1080/21577323.2013.822034","DOIUrl":"https://doi.org/10.1080/21577323.2013.822034","url":null,"abstract":"OCCUPATIONAL APPLICATIONS This study simulated rotating between assembly tasks at two different intensity levels performed for a total duration of 1 hour, during which rotation occurred every 15 minutes, every 30 minutes, or not at all. Under the scenario studied here, rotation reduced shoulder muscle fatigue compared to only performing a higher intensity task and increased fatigue compared to only performing a lower intensity task. Neither rotation frequency nor starting task significantly affected fatigue or performance. Based on the results, rotation frequency and starting task may not need substantial consideration when designing rotation schedules or plans. Generalizing the current results to actual occupational tasks, however, may be limited due to the inclusion of only two tasks, the constrained nature of the task, and the small sample size. TECHNICAL ABSTRACT Background: Rotating between tasks is widely used and considered to reduce the risk of work-related musculoskeletal disorders, though there is limited evidence that it is effective in doing so. Purpose: This study assessed the effects of rotation during assembly work involving the upper extremity, specifically focusing on rotation frequency and starting task, on shoulder muscle fatigue and task performance when included tasks loaded the same muscle group. Methods: Twelve participants completed six experimental sessions during which a simulated repetitive assembly task was performed for 1 hour either with or without rotation. When rotation occurred, it was between two intensity levels corresponding to two working heights. Results: As expected, rotating between the tasks reduced shoulder muscle fatigue compared to only performing the higher intensity task and increased fatigue compared to only performing the lower intensity task. Neither rotation frequency nor starting task had significant or consistent effects on fatigue or task performance. Conclusions: While varying the intensity level of tasks included in rotation schedules reduced muscle fatigue, this effect was not influenced substantially by either rotation frequency or starting task during the moderately demanding upper extremity assembly task examined here.","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":"53 1","pages":"176 - 189"},"PeriodicalIF":0.0,"publicationDate":"2013-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2013.822034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60122953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-07-01DOI: 10.1080/21577323.2013.828666
A. Dam, P. Eling, G. Keijsers, E. Becker
OCCUPATIONAL APPLICATIONS Employees with burnout experience a persistent, negative work-related state of mind primarily characterized by exhaustion, decreased motivation, and a sense of reduced effectiveness. Although most employees with burnout (67%) were found to apply an efficient high-effort strategy like healthy controls, significantly more employees with burnout (33%) than healthy controls (8%) applied a low-effort strategy. However, the low-effort strategy used by a significant number of burnout employees does not seem to be an adaptive way of coping with fatigue but was rather the result of a structurally reduced motivation to expend effort and/or cognitive impairments. The majority of burnout employees appeared capable of performing tasks adequately and applying high-effort strategies, but they experience substantial distress during task performance. Employers may consider temporarily providing these employees with less-demanding tasks, as a reduction in stress may enable a normalization of relevant biological processes. A small group of employees with burnout did not appear to be able to adequately perform complex as well as simple tasks, and offering such employees a cognitive behavioral treatment program for burnout may be of merit. TECHNICAL ABSTRACT Background: Several studies have shown that fatigued individuals may adapt their task performance strategically. It is not known, though, whether such an adaptation is also applied by employees with burnout who suffer from long-term fatigue. Strategic adjustments can be achieved by applying simpler response strategies with lesser demands on working memory. Should employees with burnout employ these strategic adaptations to task performance, it would explain why burnout is accompanied by compromised executive functioning and not difficulties with more automatic cognitive processes. Purpose: The purpose of this study is to investigate whether reduced cognitive performance in burnout could be explained by fatigue-related strategic adaptations of task performance. Methods: Forty employees with burnout and 40 healthy controls were presented with a task they could execute either by adopting an effective but high-effort strategy or by applying a less effective low-effort strategy. Results: Significantly more employees with burnout than healthy controls applied a low-effort strategy, even though the majority used a high-effort strategy. The employees with burnout that applied a low-effort strategy failed to maintain their performance level and reported high levels of fatigue, aversion, and effort. Conclusions: Employees with burnout do not appear to adjust their performance strategically as fatigued healthy employees do. Most employees with burnout applied a high-effort performance strategy despite high levels of distress, just like non-fatigued healthy controls. A minority of the employees with burnout applied a low-effort strategy and actually did not seem to try to perform even the simple tas
{"title":"Do Employees with Burnout Prefer Low-Effort Performance Strategies?","authors":"A. Dam, P. Eling, G. Keijsers, E. Becker","doi":"10.1080/21577323.2013.828666","DOIUrl":"https://doi.org/10.1080/21577323.2013.828666","url":null,"abstract":"OCCUPATIONAL APPLICATIONS Employees with burnout experience a persistent, negative work-related state of mind primarily characterized by exhaustion, decreased motivation, and a sense of reduced effectiveness. Although most employees with burnout (67%) were found to apply an efficient high-effort strategy like healthy controls, significantly more employees with burnout (33%) than healthy controls (8%) applied a low-effort strategy. However, the low-effort strategy used by a significant number of burnout employees does not seem to be an adaptive way of coping with fatigue but was rather the result of a structurally reduced motivation to expend effort and/or cognitive impairments. The majority of burnout employees appeared capable of performing tasks adequately and applying high-effort strategies, but they experience substantial distress during task performance. Employers may consider temporarily providing these employees with less-demanding tasks, as a reduction in stress may enable a normalization of relevant biological processes. A small group of employees with burnout did not appear to be able to adequately perform complex as well as simple tasks, and offering such employees a cognitive behavioral treatment program for burnout may be of merit. TECHNICAL ABSTRACT Background: Several studies have shown that fatigued individuals may adapt their task performance strategically. It is not known, though, whether such an adaptation is also applied by employees with burnout who suffer from long-term fatigue. Strategic adjustments can be achieved by applying simpler response strategies with lesser demands on working memory. Should employees with burnout employ these strategic adaptations to task performance, it would explain why burnout is accompanied by compromised executive functioning and not difficulties with more automatic cognitive processes. Purpose: The purpose of this study is to investigate whether reduced cognitive performance in burnout could be explained by fatigue-related strategic adaptations of task performance. Methods: Forty employees with burnout and 40 healthy controls were presented with a task they could execute either by adopting an effective but high-effort strategy or by applying a less effective low-effort strategy. Results: Significantly more employees with burnout than healthy controls applied a low-effort strategy, even though the majority used a high-effort strategy. The employees with burnout that applied a low-effort strategy failed to maintain their performance level and reported high levels of fatigue, aversion, and effort. Conclusions: Employees with burnout do not appear to adjust their performance strategically as fatigued healthy employees do. Most employees with burnout applied a high-effort performance strategy despite high levels of distress, just like non-fatigued healthy controls. A minority of the employees with burnout applied a low-effort strategy and actually did not seem to try to perform even the simple tas","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":"1 1","pages":"190 - 201"},"PeriodicalIF":0.0,"publicationDate":"2013-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2013.828666","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60122517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-06-20DOI: 10.1080/21577323.2013.815139
A. Chambers, S. Perera, R. Cham
OCCUPATIONAL APPLICATIONS Differences in gait speed control strategies when anticipating a potentially slippery floor were found across age groups, with a group of mostly young adults adopting a potentially more risky strategy consisting of increased step length. Walking across a potentially slippery floor is common in the workplace, and warnings are one way to address this potential hazard. A better understanding of the influence of warnings about potentially slippery surfaces on gait could be used during slip training interventions and prevention programs to help reduce occupational slip-related falls. Specifically, these trainings/programs might benefit from addressing how to modulate gait speed through increased cadence rather than increased step length alone. Adults in both age groups tested here implemented potentially risky proactive strategies, highlighting the need to consider workers of all ages when designing occupational slip prevention measures. TECHNICAL ABSTRACT Background: Slips and falls are a major cause of occupational injury and costs. Certain proactive gait strategies can minimize fall risk. Purpose: This study investigated the impact of anticipating slippery floors on peak required coefficient of friction and spatiotemporal gait characteristics among young and older adults, including gait speed control, during walking on dry surfaces. Methods: Eighteen young (20–33 years) and 13 older participants (55–67 years) walked across a dry surface (baseline), experienced an unexpected slip, and walked across another dry surface with warning of a potentially slippery surface (anticipation). General spatiotemporal gait parameters and required coefficient of friction during walking were derived. Results: Young and older adults decreased required coefficient of friction and increased cadence during anticipation, both of which are important in reducing slip risk. Cluster analysis revealed three gait speed control strategies: Cluster 1 = mostly young adults who increased speed, cadence, and step length during anticipation; Cluster 2 = young and older adults who walked with minimal change in speed; Cluster 3 = only older adults who decreased speed through decreasing cadence and step length. Changes in cadence and step length were significantly correlated with changes in speed in older adults; only changes in step length were significantly correlated with changes in speed among young. Conclusions: Walking with decreased required coefficient of friction and increased cadence is beneficial when anticipating a slippery floor. However, walking with increased step length (Cluster 1) could increase slip risk. Avoiding gait speed modulations on potentially slippery surfaces through changes in step length alone should be addressed in occupational slip training and prevention. Interventions aimed at reducing slip risk should focus on increasing cadence if increases in gait speed are desired. Potentially risky proactive strategies implemented highligh
{"title":"Changes in Walking Characteristics of Young and Older Adults When Anticipating Slippery Floors","authors":"A. Chambers, S. Perera, R. Cham","doi":"10.1080/21577323.2013.815139","DOIUrl":"https://doi.org/10.1080/21577323.2013.815139","url":null,"abstract":"OCCUPATIONAL APPLICATIONS Differences in gait speed control strategies when anticipating a potentially slippery floor were found across age groups, with a group of mostly young adults adopting a potentially more risky strategy consisting of increased step length. Walking across a potentially slippery floor is common in the workplace, and warnings are one way to address this potential hazard. A better understanding of the influence of warnings about potentially slippery surfaces on gait could be used during slip training interventions and prevention programs to help reduce occupational slip-related falls. Specifically, these trainings/programs might benefit from addressing how to modulate gait speed through increased cadence rather than increased step length alone. Adults in both age groups tested here implemented potentially risky proactive strategies, highlighting the need to consider workers of all ages when designing occupational slip prevention measures. TECHNICAL ABSTRACT Background: Slips and falls are a major cause of occupational injury and costs. Certain proactive gait strategies can minimize fall risk. Purpose: This study investigated the impact of anticipating slippery floors on peak required coefficient of friction and spatiotemporal gait characteristics among young and older adults, including gait speed control, during walking on dry surfaces. Methods: Eighteen young (20–33 years) and 13 older participants (55–67 years) walked across a dry surface (baseline), experienced an unexpected slip, and walked across another dry surface with warning of a potentially slippery surface (anticipation). General spatiotemporal gait parameters and required coefficient of friction during walking were derived. Results: Young and older adults decreased required coefficient of friction and increased cadence during anticipation, both of which are important in reducing slip risk. Cluster analysis revealed three gait speed control strategies: Cluster 1 = mostly young adults who increased speed, cadence, and step length during anticipation; Cluster 2 = young and older adults who walked with minimal change in speed; Cluster 3 = only older adults who decreased speed through decreasing cadence and step length. Changes in cadence and step length were significantly correlated with changes in speed in older adults; only changes in step length were significantly correlated with changes in speed among young. Conclusions: Walking with decreased required coefficient of friction and increased cadence is beneficial when anticipating a slippery floor. However, walking with increased step length (Cluster 1) could increase slip risk. Avoiding gait speed modulations on potentially slippery surfaces through changes in step length alone should be addressed in occupational slip training and prevention. Interventions aimed at reducing slip risk should focus on increasing cadence if increases in gait speed are desired. Potentially risky proactive strategies implemented highligh","PeriodicalId":73331,"journal":{"name":"IIE transactions on occupational ergonomics and human factors","volume":"1 1","pages":"166 - 175"},"PeriodicalIF":0.0,"publicationDate":"2013-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21577323.2013.815139","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60122839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}