bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Task Duration and Type of Automation Support on Human Performance and Stress in a Simulated Battlefield Engagement Task
Authors: McGarry Kathleen , Rovira Ericka , Parasuraman Raja
Published: January 2012

Automation that is meant to assist the operator by reducing stress and workload may actually increase both. Automation can be imperfect, and as a result may add to uncertainty and degrade performance when it fails. In a complex and dynamic task environment, this may lead to increased stress, which in turn may be associated with inefficient use of automation. The present study examined the relative benefits and costs of imperfect information and decision automation in a simulated battlefield engagement task. Performance and stress were evaluated for short- (10 minutes) and long-durations (30 minutes) of the task. The cost of unreliable aiding—a decrease in accuracy of appropriate target engagement selection—was greater for the decision automation than for information automation, irrespective of task length. Unreliability also slowed response times more for decision than for information automation, but only when the task was long. Subjective reports of stress also increased in the longer automated conditions. The results show that automated decision aids can improve performance when reliable. However, the price of imperfect decision automation is reduced accuracy and increased stress compared to information automation, particularly when the task must be performed for long periods.
Exploring Cognitive Strategies for Integrating Multiple-View Visualizations
Authors: Ryu Young Sam , Yost Beth , Convertino Gregorio , Chen Jian , North Chris
Published: January 2012

Visualizing information is useful for finding patterns in complex data sets, but little research has been done on how people understand multiple-view visualizations (multiple visualizations presented simultaneously). A controlled experiment was performed using different combinations of visualizations and different task types as independent variables, and qualitative and quantitative data were collected. To collect the data psychological tests, logs of the participants' interaction, eye-tracking equipment, and video recordings were used. This paper reports a portion of the results from this experiment. Main findings include that, contrary to what was suggested in previous literature, the time cost for switching between different types of visualizations (context switching) may not be significant, and that displaying the data using the same type of visualization may cause interference. Orthogonal combinations appear to aid users in finding and recognizing patterns, and focusing attention and analogical reasoning on spatial relationships may be important cognitive abilities for the given tasks.
An Initial Investigation into the Cognitive Processes Underlying Mental Projection
Authors: Jones Debra G. , Quoetone Elizabeth M. , Ferree John T. , Magsig Michael A. , Bunting William F.
Published: January 2012

The objective of this study is to gain insight into the cognitive mechanisms that enable a person to project how a system or environment will change over time. Two potential mechanisms for mental projection are examined: (1) mental simulation (performing a mental play by play) and (2) pattern matching (identifying critical features of the situation and matching those with previous experience). A study was performed in cooperation with the National Weather Service Warning Decision Training Branch in which 28 severe weather warning forecasters participated in an interval-based simulation. At three decision points in this simulation, participants were asked to assess the threat level for tornado, wind, hail, and flash flood and to delineate their rationale for each assessment. Results are presented that support the existence of pattern matching and mental simulation strategies, that suggest different strategies may be effective in different situations, and that indicate forecasters utilize both strategies.
Effects of Situation Awareness Training on Novice Process Control Plant Operators
Authors: Brooks Johnell O. , Switzer Fred S. , Gugerty Leo
Published: January 2012

This study investigated whether situation awareness training over and above current training practices could increase novice process control operators' system performance and situation awareness. We examined the possibility of explicitly training novices in such a way that they could quickly acquire some of the functional characteristics of experts and thereby more quickly improve performance and avoid errors. To answer this question, 24 two-member crews controlled a simulated process control plant. Participants who were exposed to the situation awareness training had better overall system performance in terms of both system stability and deviation from optimal operating conditions. Surprisingly, paper and pencil measures of the operators' situation awareness showed no significant increase in situation awareness after training. It appears as if carefully designed training programs have the potential to significantly increase novice operators' performance.
The Role of Experience in Operational Incident Commanders' Decision Making Expertise: Typical and Procedure-Based Decisions
Authors: Crichton Margaret
Published: January 2012

This study set out to identify the basis of decision making expertise by the operational incident commander in an industrial emergency response organisation, involving domain-specific problem solving strategies and skills, and knowledge developed through normal operations and training. Perspectives from NDM, and the specialised working memory component view in cognitive psychology were integrated as Engineers (n = 16) from a high risk industrial environment participated in a dual-task paradigm involving a context-specific computer-based decision task combined with a secondary visuo-spatial distractor task. Response times, quality, and difficulty of decisions, categorised as typical/atypical and procedure/no procedure, were examined across duration of experience (high experience/low experience). Results provide evidence of fast, high quality, low difficulty schema-based decision making. However being covered by a procedure did not assist fast recall from LTM. Targeted experiential training to develop schemas in LTM is emphasised.
The Impact of Pilot Expertise and Action Planning on Future State Projection Ability
Authors: Jodlowski Mark T. , Doane Stephanie M.
Published: January 2012

The following research examined the impact of pilot expertise and action planning on the ability to project forward a future state of an aircraft. Seventy-seven novice and expert pilots were asked in multiple trials to choose control actions that would change a current flight state depicted by cockpit instruments into a goal flight state, and then to judge whether a subsequent display of cockpit instruments showed the future state of the aircraft relative to the stated goal. Control movement selection, a measure of action planning accuracy, and future state judgment accuracy were recorded. The results suggest that expert action planning is directly linked to an ability to project forward a future state. In contrast, novice ability to project forward is independent of action planning accuracy. The results are discussed in terms of the separability of Endsley's levels of situation awareness.
The Influence of an Opponent and Time Pressure in Risky Naturalistic Decision Making
Authors: Burke Kelly A. , Murray John D.
Published: January 2012

This experiment assessed the extent to which the presence of an opponent and time pressure affected risk-taking behavior in a modified blackjack game developed by Dror et al. (1999). Eighty-two college students executed a series of blackjack hands that varied with respect to risk level (none, low, medium, high, very high, infinite), time pressure (yes/no), and presence of an opponent (no opponent, human opponent, computer opponent). Choice probability (participants' willingness to take an additional card) and choice response time were the dependent variables of interest. Consistent with previous research (Burke & Murray, 2001; Dror et al., 1999), participants were less likely to take an additional card as risk level increased. As predicted, response time data showed that participants took more time to make decisions at the low, medium, and high risk levels and that time pressure reduced response time across all risk levels. In general, the presence of an opponent led to an increase in the frequency of choosing to take an additional card across all risk levels, especially at the risk levels requiring more difficult decisions. Consistent with predictions, the findings suggest that the presence of an opponent and especially a human opponent, have an important role in the way that people make risky decisions.
Automated Speech Recognition for Modeling Team Performance
Authors: Foltz Peter W. , Laham Darrell , Derr Marcia
Published: January 2012

While team tasks provide a wealth of data on individual and team performance, techniques for modeling team communication can be quite effortful and time-consuming. Automated techniques of analyzing team discourse provide the promise of quickly judging team performance and permitting feedback to teams both in training and in operations. In previous research, techniques using Latent Semantic Analysis (LSA) have proven successful for analyzing team transcripts. However, converting the audio discourse into transcripts often requires hand transcription. In this work, we describe applying automated speech recognition (ASR) to team transcripts and using the output of the ASR to predict overall team performance. Results indicate that ASR can be used in conjunction with semantic methods of modeling team communication to provide accurate predictions of performance. The work has potential for assisting operators in the performance of their tasks because it can “listen” and in real-time evaluate free-form verbal communication from a variety of sources.
Couplings among HCI Design Parmeters cause Poor Usability
Authors: Helander Martin G.
Published: January 2012

This paper presents a formal method for usability analysis. It can be used for design of products as well software. Functional requirements (FRs) and design parameters (DPs) are first stated. Then a conversion matrix from FRs to DPs is constructed. This matrix, referred to as “Design Matrix” is analyzed with respect to its properties. A diagonal matrix will have few usability problems, whereas a coupled design will have many usability problems. Usability may hence be improved by decoupling the matrix. This can be done by: 1. Selecting other design parameters. 2. “Reengineering” the problem by selecting other functional requirements and 3. Making sure that only one abstraction level at a time is addressed during the design of the interface.
Static and Dynamic Representations of Motion
Authors: Strickland Jennifer L. , Gillan Douglas J. , Chadwick Roger
Published: January 2012

Can static cues provide information about motion? The present research compared three types of displays that showed the motion of a weather system — two static displays (lines only and lines ending in arrows) and an animated display. In Experiment 1, participants received trials in which all three displays were presented and they selected the static display that best provided the motion information in the animated display. Participants selected the static arrow display on 67% of the trials. In Experiment 2, participants received trials with one display at a time, in which they used the display to answer questions concerning the motion of the weather system. Performance with the arrow (response time and accuracy) was better than with the static line and was comparable to the animated display. These results show that static cues can be interpreted in terms of motion.
The Effect of Affect: The Hedonomic Evaluation of Human-Computer Interaction
Authors: Murphy Lauren , Stanney Kay , Hancock Peter A.
Published: January 2012

We evaluated the use of color in a human-computer interface to investigate how affective cues influence usability judgments. Yellow and green, were found to enhance performance on a cognitive flexibility task as compared to white and gray. Such an outcome suggests that color promotes positive affect. The aesthetically designed interface that promoted positive affect was also found to enhance perceptions of interface usability. This relationship, however, was only found when underlying usability was effective. When usability was poor, aesthetics made users more cognizant of the usability weaknesses. The results suggest that designers consider incorporating color into designs to help elicit positive emotion in users but that they must be aware that incorporation of aesthetics comes with the potential cost of disposing users to be more discerning of usability.
Goal Setting and Feedback: The Programmable Thermostat as a Device to Support Conservation Behavior in the User
Authors: McCalley L.T. , Midden C. J. H.
Published: January 2012

Programming clock thermostat settings involves no financial cost to the consumer and requires little effort, making it a feasible target behavior for increasing energy efficiency through automatic control of temperature setbacks according to time of day and activities of the residents. Goal setting theory was used as a framework to experimentally test the energy saving effects of goal and information specificity on planning a programming strategy and the resulting consumer performance in terms of projected savings. Specific goals were found to significantly increase planning time when specific conservation information was given and significantly decrease planning time when only a vague, “do your best” goal was given. Increased planning time did not predict performance, however, users who had never owned a clock thermostat had significantly higher projected savings in comparison with subjects currently using such a thermostat. Results are discussed in terms of implications for energy conservation programs to change thermostat behavior.
Semantic Modality in Information Design: Improving Learning Efficiency in a Multimedia Environment
Authors: Zolna Jesse S. , Catrambone Richard
Published: January 2012

Instructional theories emphasize the structural modality of the information design, that is, whether the information is visual (e.g., text vs. graphics vs. animations) or auditory. However, we argue that semantic modality, the internal cognitive representation, must also be considered in order to reduce working memory load imposed by cognitive operations. A within-subjects design comparing performance on a dual mode task demonstrated the importance of considering semantic modality. The hypothesized factor resulting in the change in performance was the type of mental processing required while physical stimuli were held constant. Significant differences in performance between control and experimental trials were found for experimental conditions in which a visual task was manipulated to interfere with an auditory task during internal coding. No significant differences were found when the experimental condition was a visual task manipulated to allow separate internal coding. The results have implications for cognitive theories of multimedia learning with respect to issues of optimal methods of information design.
Why is (Teaching) Project Management Hard in Academia?
Authors: Caldwell Barrett S.
Published: January 2012

This paper discusses issues resulting from the author's experience in teaching human factors and ergonomics design project courses, including a recent project examining features of project management software applied to academic environments. The experiences of the design project team, as well as other issues in managing the author's research lab, indicate significant issues associated with attempting to apply industry-based project management tools, processes, and expectations to a university-based teaching and learning environment. Rather than demonstrate an empirical solution to the title question, this paper presents a series of queries to examine in the context of limits and opportunities in higher education to enhance students' preparation for entering a information economy workforce.
Test of a Dynamic Footrest on Leg Swelling in Sedentary Computer Workers
Authors: Sherman Courtney , Hedge Alan
Published: January 2012

Sixteen college students (8 male, 8 female) sat with their lower legs exposed and typed text under two conditions: feet on a static footrest and feet on an identical dynamic footrest that passively moved the feet. Under both conditions, changes in calf volume, ankle circumference, calfskin temperature, postural adjustments of the lower limbs and typing performance were measured. Results suggest that the dynamic footrest improved lower leg circulation. Calfskin surface temperature was significantly higher with the dynamic footrest. There was an interaction of calf circumference change with condition, order and time-of-day. There was a marginally significant overall calf circumference change with the footrest. There was significantly less voluntary movement with the dynamic footrest. There was no significant effect of the dynamic footrest on ankle circumference or typing performance.
Issues for Human Factors Experts in Litigation: (A Panel Presentation)
Authors: Hornick Richard J. , Dan Fisk Arthur , Hendrick Hal W. , Laughery Kenneth , Olsen Richard
Published: January 2012

This panel will address business, professional, and ethical issues pertinent to providing human factors services for forensics application in expert witness testimony. Questions will be posed in areas of basic business conduct, professional interactions with counsel on both sides of the matter, challenges to introduction of HF testimony, ethical concerns including situations with HF experts on the opposing side, concluding with “your most hysterical, bizarre, frustrating, etc” experiences.
Maintenance Work in Small Aircrafts: An Ergonomic Approach
Authors: Bishu R.R. , Munuswamy M.K.
Published: January 2012

Airline line safety depends on a number of people ranging from pilots to the aviation maintenance technicians. Nowadays there is a growing recognition that maintenance errors pose a serious threat to airline safety. So, the Federal Aviation Administration has launched an extensive research in the field of human factors related aircraft maintenance. Not much research has gone into maintenance of small jets used for business and chartering purposes. For this purpose, the study was made in a private organization specializing in the maintenance of small jet aircrafts. The overall productivity of the past years was studied for various models of aircrafts and it was observed that the airframe department had a high rate of maintenance related errors. It was also evident that Falcons had a reasonably high rate of maintenance errors associated with it. Moreover it was found out that Falcon 50's and Falcon 900's had a high number of incidents associated with them. A task analysis was also done for the maintenance activities performed on Falcon 50's to identify the factors responsible for the high rate of errors. To assess the problem of human errors in the airframe department data about the incidents was collected by direct observation, informal interviews and incident data analysis. To show more light into the incidents, the incident analysis was done by interviews with the 50 employees responsible for the incidents, and the 55 incident report forms on Falcons for the years 2000–2002 were further analyzed.
To Be or Not to Be: Manager or Individual Contributor?
Authors: D'Souza Melroy E. , Lund Arnie , Batra Sanjay , Beith Barry , Lee Mark , Orr Lisa , Salzman Marilyn
Published: January 2012

Manager or individual contributor? That is the question faced by many human factors/ergonomics (HF/E) professionals after a few years of having embarked upon their careers in industry, or sometimes at the start of their careers. They are often ill equipped to understand the nuances of each role, the drivers for success, the challenges and frustrations, the opportunities, and most importantly, the people- and business aspects of each role. This panel consists of managers and individual contributors who will provide unique insights into the above areas and will appeal to many audiences. To the practitioner, it will provide real-world experiences that address the various business and professional skills needed for each role. To students and faculty, it highlights what needs to be learned, or be taught in our HF/E programs at school so that we may create well rounded, graduating HF/E professionals who are cognizant of the business demands of industry.
The Many Facets of Anti-Terrorism: A Discussion of Cooperation and Collaboration among Various Areas of Expertise
Authors: Zavod Merrill J. , Kring Jason P.
Published: January 2012

Recent events have caused an understandably dramatic increase in the attention paid to the science of homeland security and anti-terrorism. Both as a country and as individuals, we find ourselves contemplating methods to prevent, thwart, or at least attenuate terrorist activities. The war on terror, however, is unlike any war our country has fought in that the enemy is distributed, secretive, and follows no traditional “rules of war”. If we are to win this battle then, we must adapt our methods to face the challenge. Rather than military strategy, the war on terror will require a collaborative effort among individuals in a range of fields, including many areas of human factors. This panel session presents a small cross-section of topics related to antiterrorism which represent opportunities for human factors involvement. It is hoped that presentation and discussion of these topics with our colleagues will foster further thinking on and expansion of these as well as identification of other opportunities for human factors involvement in the war on terror.
Cognitive Factors in Homeland Defense: The Role of Human Factors in the Novel Intelligence from Massive Data (NIMD) Project
Authors: Gray Wayne D.
Published: January 2012

The Intelligence Community's Advanced Research and Development Activity (ARDA) recently issued 17 contracts for innovative, creative, and high-risk research to advance the state-of-the-art in technologies and methods for supporting the intelligence analyst in discovering “novel intelligence from massive data” (NIMD). An important feature of this initiative is the role it gave to cognitive factors. The Call-for-Participation said, “Thus, NIMD is about human interaction with information in a way that permits intelligence analysts to spot the telltale signs of strategic surprise in massive data sources — building tools that capitalize on human strengths and compensate for human weaknesses to enhance and extend analytic capabilities.” This symposium will provide a brief overview of NIMD as well as project reports from four of the teams that won NIMD contracts. While the approaches and projects are diverse, all attempt to bring an understanding of cognitive factors and quantitative approaches to bear on improving the intelligence analyst's success at extracting hidden patterns from massive databases.
Case-Based Reasoning for Knowledge Discovery
Authors: Whitaker Elizabeth T. , Simpson Robert L.
Published: January 2012

The Georgia Tech Research Institute's goal in the Novel Intelligence in Massive Data (NIMD) Program, is to investigate certain aspects of an intelligence analyst's preferences and analytic strategies used in the process of discovering new knowledge. We are analyzing search strategies used by analysts in an attempt to understand their current task model. Based on this understanding, we will design and prototype a software tool that applies case-based reasoning in combination with other advanced reasoning techniques to help analysts perform knowledge discovery. The main objective of our work is the development, validation and incremental improvement of a set of knowledge discovery automation aids that significantly reduces the manual searches done by intelligence analysts and increases the quality and quantity of derived intelligence. We believe that these technical improvements will depend on our explicit understanding of the cognitive issues implied by the use of advanced reasoning techniques, integrated into a next generation NIMD prototype.
A Brain-Based Adaptive Automation System and Situation Awareness: The Role of Complacency Potential
Authors: Bailey Nathan R. , Scerbo Mark W. , Freeman Frederick G. , Mikulka Peter J. , Scott Lorissa A.
Published: January 2012

The present study assessed situation awareness with individuals who differed in automation complacency potential using a brain-based adaptive automation system. All participants were administered a measure of complacency potential and performed a suite of tasks while monitoring several displays. A biocybernetic system was used to switch tasks between automatic and manual modes. For half of the participants, a psychophysiological index of engagement derived from their own EEG signals was used to control the task mode switches. The remaining participants operated under a pattern of task mode switches that were not derived from their EEG signals, but instead from records created by the participants in the other group. The results indicated that those individuals predisposed toward automation complacency demonstrated lower levels of situation awareness. Further, the lowest levels of situation awareness were observed for those participants predisposed toward automation complacency operating under a pattern of task mode switches generated by the other group. These findings suggest that adaptive automation may have the potential to reduce the effects of complacency by increasing available attentional capacity and in turn, improving situation awareness.
Emotional Intelligence: Implications for Human Factors
Authors: Matthews Gerald , Emo Amanda K. , Funke Gregory , Zeidner Moshe , Roberts Richard D.
Published: January 2012

This paper reviews the relevance to the human factors practitioner of emotional intelligence (EI), the ability to understand and manage emotion. Assessment of EI may be useful for predicting individual differences in performance in stressful operational environments. However, existing research demonstrates some difficulties in developing valid tests for EI. Self-report and objective tests for EI fail to converge well, and may be measuring different constructs. Objective tests are promising, but further research is needed to establish their predictive validity in human factors contexts. Three examples are given of applied contexts in which assessment of EI may be valuable: performance under stress, coping with anger and frustration and teamwork. Tests for EI might be used either for operator selection, or as an adjunct to training, but further research is needed to validate their use. The paper concludes with some initial guidelines for deciding whether EI is potentially relevant to a particular operational setting.
Analysis of Aiming with Tools: Proprioception
Authors: Chintapalli Nagasridhar , Ding Xuedong , Takahashi Shinya , Hallbeck M. Susan
Published: January 2012

One of the major areas of interest in the field of ergonomics is the design of hand tools. Though considerable research has produced more user-friendly tools, there has been some reluctance to use them for some tasks. It is hypothesized that this reluctance on the part of the user may be partly due to the reduction of accuracy while using those handles. A pilot study employing twenty subjects (10 males, 10 females) was undertaken to evaluate three different grip angles, between the tool and handle axis, combined with four visual availability of the target conditions. Each subject was asked to aim at the center of the target under all the twelve test scenarios, with each subject performing ten trials in each scenario. The target was a touch screen monitor. The interface was a black screen background with the center indicated by a red cross-hair. The results of this study showed that the dependent variable, accuracy, was primarily effected by the angle of the of the handle grip with respect to the tool axis and by the visual availability of the target in a manual-aiming task. The tool with the least ergonomically correct wrist position yielded the best accuracy. As expected, the blind condition was the worst, but seeing the points that had been previously hit as additional visual feedback did not improve performance. The overall implication being that the most ergonomically correct tool might not lead to the best performance unless proprioception or feedback is taken into consideration. This has direct implications for tasks such as laparoscopic surgery where a long shafted tool is used with little visual feedback.
How should Trackball Directional Movement Intuitively Relate to an End Effector?
Authors: Doné Kathryn , Takahashi Shinya , Nickel Andrew , Ding Xuedong , Hallbeck Susan
Published: January 2012

Three strategies for the trackball control of an end effector on a laparoscopic graspers tool were tested to see which strategy was most intuitive to the user. The three strategies (UURR, UDRL, UDRR) were tested on four different orientations of the hand: horizontal holding the tool as an extension of the arm while rolling the trackball with the thumb, horizontal holding the tool as an extension of the arm and forearm pronated 90 degrees while rolling with the thumb, horizontal with tool 90° to arm using the thumb, and horizontal with tool 90° to arm using the index finger to roll the ball. Twenty-four subjects, each randomly chosen to test one of the three movement strategies, performed two trials sets per hand orientation, the first to test for intuition and the second to test for the effect of training. The outcome of the trials was a number of correct and incorrect movements of the trackball to control the end effector which was simulated on a computer screen. The results were analyzed using a general linear model test on repeated measures to determine the effects of strategy and hand orientation. Analyses showed that intuitively, subjects were significantly better when the end effector moved as the trackball did (UURR). The analyses of the learned trials showed that subjects did equally well with all three strategies. From these results, it was determined that the trackball control of the forceps will be manipulated using the UURR strategy.
A Task Analysis Approach to Assessing Exposure
Authors: Ebersole Marissa L. , Armstrong Thomas J.
Published: January 2012

Lean manufacturing has created an environment where industrial jobs are continually changing and becoming more complex in nature. In current practice, each of these job changes would require a new ergonomic analysis. This research proposes that the analysis of individual tasks within a job can be added to understand the overall exposure of the job. Using this relationship, one can obtain an understanding of job exposure without a complete reanalysis. In this study, nine jobs were analyzed using observational techniques in which generic ergonomic stresses were rated on a scale from 0 to 10 at both a task and job level. When the task observations were added together and compared to the entire job, the ratings of radial/ulnar deviation differed by an average of 1.4 points on a 10-point scale. Peak force differed by an average of 1.1 points. The other ratings were all within 1 point on a 10-point scale, which is considered within consensus as defined by the scales. These support the proposed method.
A Comparison of the Roles of Univariate and Three-Dimensional Anthropometric Data in the Description of Form
Authors: Cerney Melinda M.
Published: January 2012

With the recent completion of the Civilian American and European Surface Anthropometry Resource (CAESAR), a comprehensive set of univariate and three-dimensional anthropometric data has been made available to the design community. It is now the role of the designers to determine how best to utilize these data, whether to continue designing with distance measures or to break with the traditional methods and explore the descriptive possibilities of 3D data. This paper describes a statistical comparison of the characteristics of traditional, univariate anthropometric data to three-dimensional data in the design of a seated workstation through the exploration of (1) the ability of distance data extracted from 3D landmark data to represent traditional anthropometric dimensions and (2) the degree of similarity between the design information provided by extracted distance data and the original set of three-dimensional landmark coordinates. The results suggest that three-dimensional landmarks provide a more complete archival of form than do univariate descriptors.
The Effects of a Manual Furniture Handling Device on Muscle Activity and Kinematics of the Lower Back
Authors: Paskiewicz Jessica K. , Fathallah Fadi A.
Published: January 2012

Low back disorders (LBDs) are prevalent in the manual furniture moving industry. However, few practical lifting aids are available, especially when handling objects requiring two movers. A belt system, the GRIPSystem™, has been developed to assist movers who operate in pairs while lifting awkward furniture. The purpose of this study is to evaluate the effectiveness of this manual device in reducing key low back disorders risk factors. Twelve subjects (9 male and 3 female) were recruited to participate in this study. The subjects lifted three household furniture items, at three varied weights, with and without the lifting device, while trunk kinematics and 10 muscle EMG signals were recorded. The results showed that the device significantly lowered the kinematics and muscle activity of the lower back, as well as the risk of LBDs. Other potential benefits of the device are also discussed. However, further studies are needed to confirm the device's effectiveness in reducing LBDs in the moving industry.
Exposure Assessment Strategies to Evaluate Trunk Postures during Heavy Manufacturing Work
Authors: Prabhu Hemant , Paquet Victor
Published: January 2012

The objective of this study was to identify the sources of temporal variation in trunk postures for self-paced cyclic jobs in a forging plant in order to inform job analysis sampling strategies intended to reliably estimate average long-term exposures to these postures. Repeated video recordings were made on three different individuals in each of the three different jobs over a period of fourteen days. Multimedia Video Task Analysis™ was used to evaluate the percent of time individuals spent in mild trunk flexion (i.e., exceeding 20 degrees) for each of the observation periods. Analysis of variance was used to quantify the within and between worker sources of exposure variability within shifts and across days. The within and between worker components of variability in trunk flexion was very different across the occupations. While in one occupation, no exposure to mild trunk flexion was found, the within- and between-worker components of variance were quite different for the other two occupations. This suggests that different sampling strategies may be needed to reliably estimate the average percentage of time individuals spend working in flexed trunk postures even for cyclic production jobs.
Importance of Ergonomics for the Aging Worker
Authors: Davis Kermit G. , Jorgensen Michael J , Grosch James W. , Chaffin Don B. , Redfern Mark S. , Marras William S. , Czaja Sara
Published: January 2012

The purpose of the panel will be to discuss the ramifications of the numerous aging-related declines and how they impact the risk of injury in the workplace. Specific attention will be given to how the various components of the musculoskeletal system interact with each other. The discussion will provide potential intervention strategies that accommodate for the special needs of older workers. Through the diverse backgrounds of the panelists, a more comprehensive dialogue will provide better evidence of the strength and weaknesses of the literature regarding this rapidly growing at-risk population.
Effects of Regulations on the Choice of Ergonomic Methods: A Comparative Survey of California and New York Ergonomists
Authors: Puleio Jonathan , Hedge Alan
Published: January 2012

A survey of 57 ergonomists in California and 28 ergonomists in New York State compared which of 19 ergonomic methods were used to assess potential injury risks. Results showed great variability in methods chosen by practitioners both within and between States. The Cal/OSHA regulation apparently has not standardized method selection in California. Apart from use of the NIOSH lifting equation for assessments of lifting and the Borg RPE scale for assessing exertion, there was no evidence of any standardization among practitioners in either State. There was no consensus on methods for assessing posture, repetitiveness, or force. Significant confusion was found among California practitioners regarding the content of the current Cal/OSHA regulation.
Risk Assessment Model for Carpal Tunnel Syndrome
Authors: Kong Dongjoon , Freivalds Andris , Kothari Milind J. , Naidu Sanjiv H. , Ford Robert E.
Published: January 2012

Because of the high prevalence of carpal tunnel syndrome (CTS) in the work place, there is a need for a risk assessment model for CTS that considers more than work-related risk factors. A total of 74 subjects (39 CTS patients and 35 healthy workers without any symptoms of CTS) participated in a cross-sectional study to develop a risk assessment model for CTS based on the hypothesis that a combination of personal and work-related factors contribute to the development of CTS. Personal, psychosocial and physical risk exposure information was collected and analyzed on two groups. A pseudo-univariate analysis was used to select the competitive factors from 84 candidate variables. The final multiple logistic regression model included seven factors: age, gender, right hand wrist ratio, body mass index, previous musculoskeletal disorders at hand/wrist, skill utilization, and unbalanced hand use (high repetitiveness). The Hosmer-Lemeshow test ( H c*= 1.536, d.f. = 7, p =0.981) indicated that the derived multiple logistic regression equation adequately fit the data. The correct classification performance of the model is 91%. The logistic regression model includes more personal factors than work-related factors due to two major reasons: (1) the heavier physical workload of the healthy workers than CTS patients, or (2) a higher survival rate among healthy workers.
Positions of the Computer Mouse within a Thousand Workstations
Authors: Dennerlein Jack , Johnson Peter
Published: January 2012

We completed an evaluation of a 1000 workstations at 37 companies across six states of the US determining the location of the computer mouse. A simple check list contained four categories for input device use (infrequent, primarily keyboard, primarily mouse, or mixed); six categories for pointing device location (18 horizontal areas relative to keyboard, five categories for vertical location relative to the keyboard), and three categories for the keyboard vertical position adjustability(fixed height, adjustable work-surface, keyboard tray). Over 92% of the workstations had the mouse on the right-hand side of the keyboard, and 54% were in the area immediately to the right of the keyboard. Of the workstations evaluated 79% had the mice at the same vertical level as the keyboard with 13% being placed above and 8% below the keyboard. Sixty-one percent of the workstations had the keyboard on a vertically adjustable surface whereas 38% were placed on a conventional non-adjustable desk. Only 32% have the keyboard on a vertically adjustable work-surface with the mouse directly to the right of the keyboard, the recommended setup configuration. Mouse locations varied between companies, but were fairly similar within facilities.
Using Linear Programming to Optimize Control Panel Design from an Ergonomics Perspective
Authors: Holman Grady T. , Carnahan Brian J. , Bulfin Robert L.
Published: January 2012

Linear programming (LP) for optimization of control panel layouts has been incorporating ergonomic constraints into models to reduce reaching distances required for control panel use since the 1960's. These algorithms have used a panel's frequency of use, distance from user, and transition distance as basic model variables. A new variation of the LP model for control panel design is proposed that modifies the layout from single point semidry to dual point semidry in terms of design using anthropometrics. The proposed model was applied to the design of a twelve-panel board of six-inch square panels. The model was able to take into account design factors such as control sequence, alignment, and clustering, as well as direct hand access. The resulting control panel solution minimized the reach and movement distances required by an operator. Results suggest that LP optimization can be used to construct “ergonomically designed” control panels that limit MSDs incidence and severity.
Imposing Password Restrictions for Multiple Accounts: Impact on Generation and Recall of Passwords
Authors: Vu Kim-Phuong L. , Bhargav Abhilasha , Proctor Robert W.
Published: January 2012

The most commonly used method of identification and authentication for many Web sites is username-password combinations. However, this is a notoriously weak security method because users tend to generate passwords that are easy to remember but also easy to crack. The method of proactive password checking has been proposed to improve security at little cost to memorability, because it allows users to generate their passwords but imposes restrictions to make the passwords more resistant to cracking. The present study evaluated the time and accuracy needed to generate unique passwords that satisfy different restrictions for multiple accounts, as well as the time and accuracy at recalling these passwords. Results showed that password restrictions do not necessarily improve the security of the password generated by users by making them more resistant to cracking because cracking software have become increasingly sophisticated. Although users show good recall of unique passwords generated with restrictions for multiple accounts when the number of accounts is small, the memorability for the multiple passwords decreases as the number of possible accounts increases. One way to improve the memorability of passwords for multiple accounts is to have users generate them several times, at different points of time, prior to allowing them to exit the system.
Online Chatting: User Evaluations of Current Instant Messenger Systems and Design Recommendations for Future Systems
Authors: Mayhorn Christopher B. , Leynes P. Andrew , Bink Martin L. , Hardee Jefferson B. , Fuller J. Adam
Published: January 2012

A large sample of users (N = 211) from three geographically distinct locations within the United States completed a survey to reveal a number of practical as well as social benefits to using instant messenger (IM) systems. Paradoxically, a number of these benefits were also described as common sources of frustration in different contexts. For instance, the ability to conduct multiple conversations simultaneously was described as a benefit of using IM yet sources of frustration included an inability to type fast enough to respond to everyone and confusion of message content. To compensate for past usability issues associated with IM use, users suggested a number of design recommendations to facilitate the use of future systems. The implications of this work are discussed in terms of current theories regarding technology acceptance and use.
Comparing Cascading and Indexed Menu Designs for Differences in Performance and Preference
Authors: Bernard Michael L. , Hamblin Christopher J. , Chaparro Barbara S.
Published: January 2012

Three menu layouts were compared for objective and subjective performance, as well as overall preference. The menus structures consisted of an index layout, a vertical cascading layout, and a horizontal cascading layout. Significant differences in search time were revealed between the three menu item layouts that favored the index menu layout. In addition, there was a non-reliable trend that favored the subjective opinion that the index layout was less disorientating than the other two layouts. Moreover, participants selected the index layout as their first preference choice more than the other two layouts. The poorest performer, both objectively and subjectively, was the horizontal layout. Possible reasons for these outcomes are discussed.
A Human Factors Vulnerability Evaluation Method for Computer and Information Security
Authors: Kraemer Sara , Carayon Pascale
Published: January 2012

There is a current lack of human factors identification and analysis methods in computer and information security. Previous research has focused on micro-level issues, such as task analyses and usability studies of security methods such as smart cards, passwords, and biometric devices. The purpose of this research is to develop a framework for identifying human factors and organizational issues contributing to computer and information security vulnerabilities and breaches. This framework is applied in conjunction with technical security audits. The purpose of this research is to test, develop, and refine the proposed methodology. This study examines the methodology with known computer and information technical vulnerabilities through semi-structured interviews with network administrators. These interviews yielded results in the form of methodology refinements and developments and two case studies of technical security vulnerabilities, using what is called the Human Factors Vulnerability Analysis, or HFVA.
Shift Changes among Emergency Physicians: Best of Times, Worst of Times
Authors: Wears Robert L. , Perry Shawna J. , Shapiro Marc , Beach Christopher , Croskerry Pat , Behara Ravi
Published: January 2012

The need for 24-hour emergency care requires emergency department (ED) staff to work in shifts. Shift changes have long been viewed as risky times, for failures in the transfer of information, authority, or responsibility care can result in adverse events.

We observed shift transitions in the ED as part of a study on safety in emergency care. We found that, in addition to being an expected point of failure, transitions were also, unexpectedly, associated with recovery from failure. We report two illustrative case studies, and examine implications for strategies aimed at reducing the number of and volume of transitions.
Collecting Workers' Perceptions of Performance Obstacles in Outpatient Surgery
Authors: Hundt Ann Schoofs , Carayon Pascale , Ayoub Phillip J. , Alvarado Carla J.
Published: January 2012

The aim of this study was to gather information from staff of outpatient surgery centers concerning their perception of the patient safety/quality of care issues at their Center and the performance obstacles they face when doing their work. In addition we wished to determine whether performance obstacles research (Brown & Mitchell, 1988; Peters et al, 1985) can be applied to the conceptual framework that serves as the basis for all of our patient safety research (Smith & Carayon, 1989, 1995; Carayon & Smith, 2000).

We distributed open-ended surveys to all health care providers in five local outpatient surgery centers. Based on previous work conducted in the area of performance obstacles (Brown & Mitchell, 1988; Peters, et al, 1985) we asked the caregivers to identify instances when they felt their performance was challenged or below par, as well as instances when they were able to perform their job very well. Because the population we surveyed is not familiar with the totality of the work system model as defined by Smith & Carayon (1989, 1995) and Carayon & Smith, (2000), we provided the elements of the work system as examples to the respondents. The resounding themes caregivers listed as significant performance obstacles included inter-provider coordination and communication of care, equipment, work space, scheduling, time pressure and staffing issues.